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  • 1995-1999  (1,216)
  • 1999  (313)
  • 1996  (903)
  • Life and Medical Sciences  (725)
  • Human
  • Immunohistochemistry
  • Nuclear reactions
  • 1
    ISSN: 1534-4681
    Keywords: Esophageal cancer ; Treatment ; Prognosis ; Cell cycle ; Immunohistochemistry ; Cyclin-dependent kinases inhibitor
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background: p21Waf1/Cip1 (p21), p27Kip1 (p27), p53, and Rb play critical roles in cell cycle regulation and may influence the clinical behavior of tumors. We examined whether their expression is useful to predict survival of patients with esophageal squamous cell carcinoma (ESC). Methods: Expression of p21, p27, p53, and Rb was studied by the immunohistochemical method in specimens from 62 patients with curatively resected ESC tumors and scored by a computerized image analysis system. Results: The median expression scores of p21, p27, p53, and Rb (14, 12, 27, and 50, respectively) were used as cut-off points to define low and high expression groups for each protein. The 5-year survival rate for the high p21 expression group was 68%; that for the low expression group was 31% (P = .0062). p27, p53, and Rb were not correlated with overall survival. When patients were categorized into four groups based on p21 expression level and lymph node involvement (pN), the survival curves were significantly different (P = .0017). Thus, patients without lymph node involvement but with low p21 expression had survival similar to that of patients with lymph node involvement and high p21 expression. Multivariate analysis showed that age (P = .0102), lymph node involvement (P = .0076), and p21 (P = .0276) were independent prognostic factors. Conclusions: Expression of p21 is an independent prognostic factor in curatively resected ESC. Definition of new subgroups of patients based on p21 expression may help to enhance the stratification of stage.
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Annals of surgical oncology 6 (1999), S. 70-74 
    ISSN: 1534-4681
    Keywords: Angiogenesis ; Melanoma ; Metastasis ; Immunohistochemistry ; Microvessels.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background: Angiogenesis has been correlated with melanoma progression, but its role in melanoma metastasis is unclear. Methods: To determine whether angiogenesis correlates with the presence of melanoma metastases, we compared the number of microvessels in the primary melanomas of 12 patients presenting with metastases to those of 13 patients without metastases. Patient groups were matched for gender, age, tumor depth, and histological type and anatomical location of the primary melanoma. Microvessels were stained with factor VIII antibody and counted. Results: Microvessel counts were significantly greater for the metastatic than the nonmetastatic melanomas (51.63 ± 14.95 vs. 24.86 ± 8.415; P 〈 .0001). One hundred percent of the metastatic melanomas had a mean microvessel count of ≥ 37, whereas only 8% of the nonmetastatic melanomas had a mean microvessel count of ≥ 37 (sensitivity = 1.00, specificity = .92). Interestingly, patients with lymph node metastases had significantly lower microvessel counts than did patients with distant metastases (42.00 ± .482 vs. 58.50 ± 16.40; P 〈 .05), and significantly higher microvessel counts than did patients without metastases (42.00 ± 3.482 vs. 24.86 ± 8.415; P 〈 .001). Conclusions: An increased number of microvessels in the primary tumors of patients with melanoma correlates with the simultaneous presence of metastases. This suggests that angiogenesis may be important in the process of melanoma metastasis.
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  • 3
    ISSN: 1534-4681
    Keywords: Gastric cancer ; Intestinal/diffuse histotype ; P53 ; Immunohistochemistry ; Prognostic factors ; Multivariate analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background: The prognostic value of p53 nuclear accumulation in gastric cancer is still unclear, as shown by the discordant results still reported in the literature. In this study, we evaluated the correlation between p53 accumulation and long-term survival of patients resected for intestinal and diffuse-type gastric cancer. Methods: Eighty-three patients with carcinoma of the intestinal type and 53 patients with carcinoma of the diffuse type were included in the study. Immunohistochemical staining of the paraffin sections was performed by using monoclonal antibody DO1; cases were considered positive when nuclear immunostaining was observed in 10% or more of the tumor cells. Prognostic significance of different variables was investigated by univariate and multivariate analysis. Results: p53 positivity was found in 51.8% of intestinal-type and 50.9% of diffuse-type cases. No significant correlation between the rate of p53 overexpression and age, sex, tumor location, tumor size, depth of invasion, lymph node involvement, distant metastases, and surgical radicality was found in the two groups of patients. A statistically significant difference in survival rate was observed between p53-negative and p53-positive cases in the intestinal type (P 〈 .05), confirmed by multivariate analysis (P 〈 .005; relative risk = 3.09). On the contrary, no correlation with survival was found in diffuse-type cases according to p53 overexpression. Conclusions: These results suggest that the immunohistochemical detection of p53 accumulation is a useful indicator of poor prognosis in the intestinal but not in the diffuse type of gastric cancer, and are indicative of distinct molecular pathways and pattern of progression in the two histotypes.
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  • 4
    ISSN: 1530-0358
    Keywords: Carcinoembryonic antigen ; Colorectal neoplasms ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract PURPOSE: Carcinoembryonic antigen is assumed from the results of several experiments to be associated with invasion of colorectal carcinoma by adhesion or contact inhibition. The patterns and the intensity of carcinoembryonic antigen distribution in colorectal carcinoma were assessed to verify whether they were correlated with malignant potential from those biologic characteristics. METHODS: Carcinoembryonic antigen distribution was tested in the archival samples of 149 colorectal carcinomas by immunohistochemistry, using three characterized anti-carcinoembryonic antigen monoclonal antibodies: T84.66, PR1A3, and PR3B10. The distribution patterns in neoplastic tissue were categorized into unstained, apicoluminal, and diffuse-cytoplasmic patterns. Tumor, invasive tumor margin, and tissue surrounding the tumor were examined. RESULTS: Although all three antibodies revealed a positive correlation, T84.66 showed better discrimination than the others. Although none of the negative staining of the tumor or invasive tumor margin showed recurrence, the apicoluminal pattern showed recurrence, and the diffuse pattern showed the most frequent recurrence (P〈0.01). Recurrence was also associated with staining intensity in the apicoluminal pattern in both the tumor and invasive tumor margin (P〈0.05). Infiltrative tumor growth and lymph node metastasis were more frequent in cases of positive staining in tissue surrounding the tumor. Patients with the apicoluminal pattern achieved longer survival than patients with the diffuse-cytoplasmic pattern in the invasive tumor margin (P=0.024) by a multivariate analysis including tumor stage and histologic differentiation. CONCLUSION: The distribution of carcinoembryonic antigen in tumors and surrounding tissue seems to be closely correlated with invasiveness and metastatic behavior in colorectal carcinoma. Carcinoembryonic antigen immune staining can be considered as an efficient tool to determine groups with risk of recurrence.
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  • 5
    ISSN: 1534-4681
    Keywords: Breast carcinoma ; Sentinel node ; Axillary lymphadenectomy ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background: Sentinel lymphadenectomy is highly accurate for identifying axillary metastasis from a primary breast carcinoma. Nonsentinel axillary lymph nodes (NSNs) are unlikely to contain tumor cells if the axillary sentinel node (SN) is tumor free. We previously showed that the size of the primary tumor and the size of its SN metastasis predict the risk of NSN tumor involvement detected by hematoxylin and eosin staining. This study used immunohistochemical staining (IHC) to determine the likelihood of NSN axillary metastasis in the presence of SN metastasis. Methods: Between 1991 and 1997, axillary lymphadenectomy was performed in 156 women (157 axillary basins) who had primary breast carcinoma with SN metastasis. By hematoxylin and eosin staining, we identified NSN metastasis in 55 axillae (35%). IHC was then used to re-examine all NSNs (1827 lymph nodes) from the remaining 102 axillae. The incidence of IHC-detected NSN involvement was analyzed with respect to clinical and tumor characteristics. Results: By using IHC, we identified NSN metastasis in 15 (14.7%) of the 102 axillae. By multivariate analysis, the size of the SN metastasis (P = .0001) and the size of the primary tumor (P = .038) were the only independent variables predicting NSN metastasis determined by using either hematoxylin and eosin staining or IHC. Only the number of SN metastases (1 vs. 〉1) was a significant (P = .04) predictor of IHC-detected NSN metastasis. Conclusions: Use of IHC increases the likelihood of detection of NSN metastasis, and the risk of IHC-detected metastasis increases with the size of the SN metastasis and the size of the primary tumor. If SN involvement is micrometastatic (≤2 mm) or detected by using IHC, tumor cells are unlikely to be found in other axillary lymph nodes in patients with a small primary tumor. The clinical significance of micrometastatic disease in lymph nodes is controversial, and a prospective randomized study is necessary to resolve this important issue.
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Surgical and radiologic anatomy 21 (1999), S. 139-141 
    ISSN: 1279-8517
    Keywords: Anatomy ; Human ; Cross-section ; Computer-assisted instruction ; Education ; Medical
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The NPAC visible human viewer (NPAC VHV), graphical interface written in JAVA, freely accessible by the Web, allows the display of anatomic cross-sections of the Visible Human Project developed by the National Library of Medicine. In April 1997, the Medical Media Library of Lyons undertook the construction of a French-language mirror site of the NPAC VHV. The aim of this work is to evaluate first year utilisation of this site. From May 1st, 1997 to April 30th, 1998, the mirror site was consulted 34,752 times. In 45.14% of cases, the request came from France, in 4.42% of cases from Belgium, in 3.98% from Canada and in 2.12% from Switzerland. Other connections came either from a country responsible for fewer than 1% of connections or from unidentified computers. Data analysis showed a peak of connections between 15:00 and 17:00, and an increased number of connections from September to March 1998. The NPAC VHV is housed in 5 sites in the world. It is a software very simple to use. As the figures have no legends, it is more appropriate for group teaching than for self-teaching.
    Type of Medium: Electronic Resource
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  • 7
    ISSN: 1437-2320
    Keywords: Key words Von Hippel-Lindau disease (vHL) ; Multiple spinal hemangioblastomas ; vHL protein ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We report on a 57-year-old male presenting with radicular pain in the nerve roots of L5 and S1 on the right side and dysuria. Magnetic resonance imaging (MRI) of the lumbar spine showed multiple (up to 20) small, intradural enhancing nodules attached to the cauda equina down to the sacrum, the largest 1 cm in diameter at the level Th12/ L1 compressing the conus. Additionally, small nodules in the cervico-thoracal region adjacent to the cord, but no cerebellar or cerebral abnormalities, were detected in a consecutive MRI of the remaining neuroaxis. The histology of a resected lesion at Th12/L1 revealed hemangioblastoma of the reticular type. Together with a history of left eye enucleation performed 17 years ago for angiomatosis of the retina and the immunohistochemical detection of von Hippel-Lindau (vHL) protein within the removed spinal hemangioblastoma, a diagnosis of vHL disease was established. Family history and screening for visceral manifestations of vHL disease were negative. In contrast to cerebellar or solitary spinal hemangioblastomas, multiple spinal hemangioblastomas without cerebellar involvement in vHL represent unusual manifestations. Unlike the case for solitary lesions in non-syndromic patients, a surgical cure does not seem feasible in this case. The role of treatment modalities is discussed.
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  • 8
    ISSN: 1437-1596
    Keywords: Key words Forensic pathology ; Wound age ; determination ; Immunohistochemistry ; Morphometrical analysis ; Interleukin-1α (IL-1α)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Law
    Notes: Abstract An immunohistochemical and morphometrical study on the temporal expression of interleukin-1α (IL-1α) was performed on 40 human skin wounds with different wound ages. Immunohistochemically, polymorphonuclear neutrophils mainly showed positive reactions for IL-1α in wounds aged between 4 h and 1 day, but with increasing wound age, neutrophils were no longer present, and macrophages and fibroblasts were positively stained. Morphometrically, the ratio of the number of IL-1α-positive infiltrating cells to the total number of infiltrating cells was evaluated. A considerable increase in the IL-1α-positive cell ratio was observed in wound specimens aged 4 h to 1 day, and the maximum ratio was 46.5% in a 7 h-old wound. The mean value of the IL-1α-positive ratio in 10 wound specimens with different wound ages between 4 h and 1 day was 32.8 ± 9.7%. In most cases the ratio of IL-1α-positive cells gradually decreased in wounds aged between 1.5 and 21 days to less than 30%, and the mean value was 17.5 ± 7.2% (n = 27). These results suggest that ratios of IL-1α-positive cells considerably exceeding 30%, indicate a postinfliction interval of 1 day or less.
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  • 9
    ISSN: 1437-1596
    Keywords: Key words Poisoning ; Benfuracarb ; Carbofuran ; Human ; Blood ; Urine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Law
    Notes: Abstract We describe here three cases involving acute fatalities due to benfuracarb ingestion and the forensic toxicological implications. Benfuracarb, a carbamate insecticide and its main metabolite carbofuran, were detected using thin layer chromatography (TLC) and gas chromatography/mass spectrophotometry (GC/MS) after extraction with ethyl acetate and then quantified using gas chromatography (GC) equipped with NPD. The blood levels of benfuracarb and carbofuran were in the range of 0.30∼2.32 μg/ml and 1.45∼1.47 μg/ml, respectively. Benfuracarb was not detected in urine, but carbofuran was detected in the range of 0.53∼2.66 μg/ml.
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    International journal of legal medicine 113 (1999), S. 19-25 
    ISSN: 1437-1596
    Keywords: Key words Head injury ; Diffuse axonal injury ; Immunohistochemistry ; Neuron-specific enolase ; Amyloid precursor protein
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Law
    Notes: Abstract Recently, it has been reported that a diagnosis of diffuse axonal injury in cases with a short survival period can be made with the use of immunolabelling for β-amyloid precursor protein (APP). We examined whether immunostaining for neuron-specific enolase (NSE) can also be a useful marker for the detection of axonal injury in its early stages. Sections of the corpus callosum from 19 cases of head injury and from 9 cases of no head injury were immunostained for NSE and stained by the standard Holmes’ silver method. For comparison, serial sections from several cases were immunostained for APP. Immunostaining for NSE as well as for APP, labelled injured axons in head injury cases with as early as 1.5 h survival where Holmes’ staining failed to detect any changes of axons. Since NSE and APP labelled only injured axons but not normal axons, the results were readily interpretable. These findings indicate that NSE should be an effective marker for the detection of axonal injury in its early stages.
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  • 11
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 125 (1999), S. 389-396 
    ISSN: 1432-1106
    Keywords: Key words Neck muscles ; Vibration ; Proprioception ; Sound localization ; Space perception ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  The effect of transcutaneous vibration of the posterior neck muscles on the lateralization of dichotic sound was investigated in human subjects. Two-alternative forced-choice (left/right) judgements were made on acoustic stimuli presented with different interaural level differences via headphones during neck-muscle vibration. A shift of the subjective auditory median plane toward the side contralateral of vibration was found, indicating that the sound was perceived as shifted toward the side of vibration. The mean magnitude of the vibration-induced intracranial shift was 1.5 dB. The results demonstrate a neck-proprioceptive influence on sound lateralization and suggest that this proprioceptive input is used for a central-nervous transformation of auditory spatial coordinates onto a body-centered frame of reference.
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  • 12
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 125 (1999), S. 435-439 
    ISSN: 1432-1106
    Keywords: Key words Transcranial magnetic stimulation ; Plasticity ; Synchronization ; Motor system ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  We used focal transcranial magnetic stimulation to examine the effects of 120 synchronized thumb and foot movements on the motor output map of the right abductor pollicis brevis muscle (APB) (experiment 1). To evaluate the performance, the latencies between the onset of the electromyographic activity (EMG) of the two muscles were measured. As control, 120 asynchronous thumb and foot movements were performed (experiment 2). Exclusively in experiment 1, the center of gravity (CoG) of the output map moved medially in the direction of the foot representation area (mean 7 mm, P〈0.05) and returned into its original location within 1 h. In experiment 2, the CoG remained unchanged (mean displacement, 0.68 mm into a lateral direction; not significant). The effect in experiment 1 was independent of an improvement in performance. We conclude that a short-lasting training of synchronous movements induces modulations of motor output maps which probably occur due to interactions between hand and foot representation areas in the motor cortex.
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  • 13
    Electronic Resource
    Electronic Resource
    Springer
    Journal of comparative physiology 185 (1999), S. 297-304 
    ISSN: 1432-1351
    Keywords: Key words Odor coding ; Learning ; Enhanced sensitivity ; Rabbit ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The olfactory system is faced with a particular problem – the high dimensionality and inherent unpredictability of the chemical world. Most natural odorants encountered in everyday life are complex mixtures of many different volatiles. This means that from the outset the olfactory system has to contend with a great and often unpredictable diversity of molecules, making it difficult for stable primary features of the chemical world to be mapped onto the sensory surface. One solution to such unpredictability is provided by learning. Learning confers flexibility, enabling individuals of a given species to acquire and make use of the most appropriate information in a particular environment. Two examples of this are presented: learning of maternal odors in neonatal rabbits, including evidence that the sensory surface itself may be influenced by environmental conditions so as to enhance sensitivity to molecules of particular ecological relevance, and cross-cultural human studies suggesting that experience with everyday odors influences not only the way these are evaluated, but also their perceived intensity. It is concluded that an adequate understanding of odor coding and olfactory function will not be possible without taking such experience-dependent factors into account.
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  • 14
    Electronic Resource
    Electronic Resource
    Springer
    International journal of colorectal disease 14 (1999), S. 272-276 
    ISSN: 1432-1262
    Keywords: Key words  Colorectal cancer ; Angiogenesis ; Vessel density ; Prognosis ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  Angiogenesis is essential for tumor growth and metastasis, and vascular density is known as an independent prognostic factor in several tumor entities. We studied the prognostic relevance of vascular density in colorectal cancer, examining 146 patients treated surgically for cure. Tumor sections were immunostained with JC70, an endothelial cell marker. Microvessel quantification used light microscopy. The slides were scanned at a low magnification, and individual microvessel counts were made on a ×200 field in the area of the most dense neovascularization. Vascular density was found to be 75±27/visual field and to be independent of age, sex, pT and pN categories, tumor recurrence, and overall survival. Overall survival in the subgroup of patients with tumor recurrence was significantly shorter with tumors of greater vessel density (〉75) than in those of less vessel density (〈75). Multivariate analysis showed microvessel count to be an independent prognostic factor for the overall survival rate of patients with tumor recurrence; among these patients there was also a significant difference in the relapse-free survival rates between the hypovascular and the hypervascular groups. Our findings suggest that the microvessel density of the primary tumor determines the speed of tumor recurrence after metastatic disease has been triggered by other, unknown mechanisms. Although tumor vascularization can be linked to the aggressiveness of colorectal cancer, it has no value as a new prognostic marker in clinical practice.
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  • 15
    ISSN: 1437-1596
    Keywords: Key words Brain injury ; Cortical contusion ; Inflammatory reaction ; Immunohistochemistry ; Wound ; age
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Law
    Notes: Abstract The time-dependent inflammatory cell reaction in human cortical contusions has been investigated during the first 30 weeks after blunt head injury. Immunohistochemical staining was carried out using CD 15 for granulocytes and LCA, CD 3 and UCHL-1 for mononuclear leucocytes. In order to provide reliable data for a forensic wound age estimation, the intensity of the cellular reaction was evaluated with a quantitative image analysis system. CD 15-labelled granulocytes were detectable earliest 10 min after brain injury, whereas significantly increased numbers of mononuclear leucocytes occurred in cortical contusions after a postinfliction interval of at least 1.1 days (LCA), 2 days (CD 3) or 3.7 days (UCHL-1), respectively.
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  • 16
    ISSN: 1437-773X
    Keywords: Key words Gastrointestinal stromal tumor ; Gastrointestinal autonomic nerve tumor ; Electron microscopy ; Immunohistochemistry ; Gastrointestinal tract
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Sixteen gastrointestinal stromal tumors (GISTs) were studied by immunohistochemical analysis and an ultrastructural procedure. The tumor locations were as follows: esophagus (2), stomach (7), small intestine (3), and large intestine (4). Four of the lesions were classified as malignant, 2 as borderline, and 10 as benign. On the basis of the immunohistochemical analysis, the tumors were classified as follows: 1 as myogenic type, 2 as Schwann cell type, 8 as Cajal cell type (including 2 gastrointestinal autonomic nerve tumors, GANTs), and 5 as mixed-cell type. In each subtype the phenotype was compared to the ultrastructural findings. Myogenic and Schwann cell type revealed ultrastructurally smooth muscle differentiation and schwannian tumor. All 8 tumors of the Cajal cell type revealed interdigitating cytoplasmic processes with occasional clusters of filopodia. Two tumors were subdivided as GANT. Five tumors of mixed-cell type were composed of a mixture of cells with variable myogenic features or variable neural differentiation. We confirmed in this study that immunohistochemical analysis reflected electron microscopic findings.
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  • 17
    Electronic Resource
    Electronic Resource
    Springer
    Pediatric surgery international 15 (1999), S. 192-194 
    ISSN: 1437-9813
    Keywords: Keywords Internal anal sphincter achalasia ; Innervation ; PGP 9.5 ; Synapse ; Synapsin I ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Internal anal sphincter achalasia (IASA) is a condition with a clinical presentation similar to Hirschsprung's disease, but with the presence of ganglion cells on rectal biopsy. The diagnosis of IASA is made on anorectal manometry, which demonstrates the absence of a rectosphincteric reflux on rectal balloon inflation. In order to understand the nature of neuronal abnormalities in this condition, we performed immunohistochemistry using PGP 9.5 (a general neuronal marker) and synapsin I (a presynaptic marker) in IAS specimens from 10 patients with IASA and 8 normal controls. In the IAS of normal controls, there were many PGP 9.5 and synapsin I-positive nerve fibers. In IASA PGP 9.5-immunoreactive fibers were markedly reduced and synapsin I-positive fibers were either absent or markedly reduced. Our findings demonstrate that the IAS in achalasia patients has defective intramuscular innervation as well as defective innervation of the neuromuscular junction, thereby contributing to the motility dysfunction.
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  • 18
    Electronic Resource
    Electronic Resource
    Springer
    International journal of clinical oncology 4 (1999), S. 343-347 
    ISSN: 1437-7772
    Keywords: Key words KAI1, Ovarian tumors ; PCR ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background. KAI1 is a potential metastasis suppressor gene for prostate cancer. Decreased expression of KAI1 mRNA has been shown to be associated with the formation of metastasis and the progression of prostate, lung, breast, pancreatic, and bladder cancer. It has also been reported, however, that KAI1 expression is unchanged in metastatic and nonmetastatic esophageal and gastric cancer. We performed the present study to investigate the function of KAI1 in the progression and/or metastasis of ovarian cancer. Methods. We investigated the mRNA expression levels of the KAI1 gene, using quantitative polymerase chain reaction (PCR), in 29 ovarian tumors (1 adenoma, 2 low- malignant potential tumors, 9 adenocarcinomas without metastasis, and 17 adenocarcinomas with metastasis), seven ovarian cancer cell lines, and two normal ovaries. Using a thermal cycler, we found that the KAI1 gene was amplified in parallel with an internal control gene, β-Actin. The relative expression ratio (KAI1/β-Actin) as measured by densitometry was used to evaluate gene expression. Immunohistochemical localization of the KAI1 protein in ovarian cancer tissues was confirmed by the avidin-biotin peroxidase complex (ABC) method. Results. The mRNA expression levels of KAI1 were consistent in normal ovary, ovarian tumor samples, and ovarian cancer cell lines. No statistically significant difference in the KAI1 mRNA expression level was found in ovarian cancer samples with or without metastasis. Immunohistochemistry revealed that the KAI1 protein was expressed in the cell membranes of ovarian cancer cells. Conclusions. Our results suggest that reductions in KAI1 mRNA expression are not involved in either the progression or metastasis of ovarian carcinomas.
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  • 19
    ISSN: 1437-773X
    Keywords: Key words Basement membrane ; Ladsin ; Laminin-5 ; Immunohistochemistry ; Immunoelectron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Ladsin, a homolog of laminin-5, is a large cell-adhesive protein with potent cell-scattering activity. In the present study, we investigated, by immunohistochemistry, the distribution of ladsin in a wide range of normal adult human epithelial tissues along with that of integrin subunit α3 as a marker of integrin α3β1, which is the primary receptor of ladsin. Our results demonstrated that ladsin was localized in the basement membranes of almost all the epithelial tissues with coexisting integrin subunit α3 along the cell membranes, suggesting that their interaction is important in the maintenance of normal architecture and function of these membranes. Only cytoplasmic localization of ladsin was observed in the fundic glands, hepatocytes, renal tubuli, and acini of the mammary glands, and in these tissues, integrin subunit α3 was also localized in the cytoplasm. Both ladsin and integrin subunit α3 were absent in the acini of the pancreas, major salivary glands, and bronchial glands. These tissue- and cell type-specific localizations of ladsin and integrin subunit α3 likely reflect the differences in their role and function in each tissue.
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  • 20
    ISSN: 1437-7772
    Keywords: Key words Hepatocellular carcinoma ; Carcinosarcoma ; Mesenchymal differentiation ; Immunohistochemistry ; Hepatectomy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We report a case of hepatocellular carcinoma associated with mesenchymal differentiation, which was identified as a true carcinosarcoma based on thorough pathologic examination. A 48-year-old man presented with a giant mass in the lateral segment of the liver. It was resected by lateral segmentectomy combined with total gastrectomy. Microscopically, the tumor consisted of hepatocellular carcinoma, osteosarcoma, and undifferentiated sarcomatous components. The undifferentiated sarcomatous components were positive for cytokeratin, whereas the osteosarcomatous components were negative for cytokeratin and positive for S100. To our knowledge, this is only the second known case in which mesenchymal differentiation was immunohistochemically demonstrated in liver carcinosarcoma.
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  • 21
    Electronic Resource
    Electronic Resource
    Springer
    International journal of clinical oncology 4 (1999), S. 78-83 
    ISSN: 1437-7772
    Keywords: Key words CD44 ; Colon cancer ; Liver metastasis ; Cellular localization ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background. The functional heterogeneity of the cell adhesion molecule family CD44 is explained by differences in its activity, which is regulated by alterations in the distribution of its cellular localization. The aim of the current study was to evaluate the functional differences in cancer cells according to variations in the cellular localization of CD44. Methods. Paraffin-embedded tissue sections of 34 colon cancers (obtained from 17 patients with liver metastasis and 17 without liver metastasis) were investigated. These tumors were classified according to the predominant pattern of cellular localization of CD44 (the isoforms CD44H, CD44v6, and CD44v9). For each CD44 isoform, the functional differences were investigated for a correlation between localization patterns and Ki-67 labeling index (to indicate cell proliferative activity), and for a correlation between localization patterns and liver metastasis. Results. On staining for CD44H, tumors displayed three localization patterns. One pattern, in which CD44H was expressed on the basal or basolateral side of the plasma membrane in cancer cells, showed a higher Ki-67 labeling index than other localization patterns (P 〈 0.01), and a higher rate of the basolateral localization pattern was observed in patients with liver metastasis than in those without (P = 0.02). On staining for CD44v6 and CD44v9, tumors showed four and three localization patterns, respectively. No significant differences in localization patterns were found in analyses of the Ki-67 labeling index and liver metastasis for either CD44v6 or CD44v9. Conclusions. A functional correlate of CD44H localization patterns was detected. In particular, cancer cells in which CD44H was localized at the basal or basolateral membranes were closely associated with high proliferative activity and high liver metastatic potential.
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  • 22
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    Pediatric surgery international 15 (1999), S. 540-542 
    ISSN: 1437-9813
    Keywords: Key words Infantile hypertrophic pyloric stenosis (IHPS) ; Elastic fibers ; Elastin ; Connective tissue ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Infantile hypertrophic pyloric stenosis (IHPS) is characterized by hypertrophy of the pyloric muscle, causing pyloric-channel narrowing and elongation. The rigidity of the muscle is increased, which is characterized as an “olive.” Elastin is an insoluble protein that forms the major structural component of the elastic fibers and maintains the tensile strength of the tissues. To understand the possible histologic and molecular basis of the elasticity of the hypertrophic muscle in IHPS, we determined the distribution of the elastic fibers and elastin expression using Victoria blue van Gieson (VVG) staining and immunohistochemistry. In IHPS, the number of elastic fibers in the connective tissue was significantly increased in the thickened connective-tissue septa (CTS) compared with normal control specimens. In normal pyloric muscle, weak to moderate elastin immunoreactivity was observed in the CTS while no immunoreactivity was observed among the muscle fibers. In IHPS, strong immunoreactivity of elastin was observed in the CTS and moderate immunoreactivity among the hypertrophic smooth-muscle fibers. Our findings suggest that the increase on elastic fibers and elastin expression in the pyloric muscle in IHPS may play an important role in the development of pyloric-muscle rigidity, causing pyloric-canal obstruction.
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  • 23
    ISSN: 1432-2307
    Keywords: Key words Tenascin-C ; Laryngeal carcinoma ; Immunohistochemistry ; In situ hybridization ; Cell proliferation ; Cell migration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  Tenascin-C (TN-C) is an extracellular matrix glycoprotein upregulated in various pathological processes. In this study, we investigated its distribution in dysplasia and carcinoma of the human larynx using immunohistochemistry and in situ hybridization (ISH) techniques. In all cancer tissues, TN-C immunostaining was markedly increased in the stroma, especially around the cancer cell nests. In addition, cytoplasmic staining of cancer cells was also observed in 62.5% of the invasive cases, the cells being distributed in the periphery of the nests adjacent to the stroma. TN-C mRNA signals in cancer cells were detected in all six cases examined by ISH. Furthermore, in vitro evaluation of the roles of TN-C demonstrated an increase in the proliferating cell fraction in a dose-dependent manner. In a wound closure assay, the addition of TN-C promoted migration. We conclude that TN-C secreted by cancer cells may be involved in their proliferation and migration in an autocrine fashion.
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  • 24
    ISSN: 1432-2307
    Keywords: Key words Peroxisomes ; Hepatocellular tumors ; Immunocytochemistry ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  A significant reduction of catalase activity, a peroxisomal marker enzyme, occurs in human hepatic neoplasias, but no information is available on other peroxisomal proteins. We have studied by means of immunohistochemistry four specific proteins of peroxisomes (catalase and three enzymes of lipid β-oxidation) in human hepatocellular tumors of various differentiation grades from adenoma to anaplastic carcinoma. In all tumors, except the adenomas, the tumor cells contained fewer peroxisomes than extrafocal hepatocytes and the reduction of antigenic sites in the tumor types generally correlated with the degree of tumor dedifferentiation as assessed by classical histopathological criteria. Two poorly differentiated tumors had no detectable peroxisomes at all. There were no major differences in the intensities of the immunocytochemical staining for all four studied peroxisomal antigens in different tumors, suggesting that the neoplastic transformation affects the biogenesis of the entire organelle and not merely the individual peroxisomal enzyme proteins. Some tumors exhibited a distinct peripheral distribution of peroxisomes. In cases with associated liver cirrhosis, the hepatocytes in the adjacent liver showed marked peroxisome proliferation, forming large perinuclear aggregates, occupying occasionally the entire cytoplasm. Taken together, our observations indicate that peroxisomes are significantly altered in both hepatocellular tumors and liver cirrhosis and, thus, could be responsible for some of the metabolic derangements observed in those disease processes.
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  • 25
    ISSN: 1432-2307
    Keywords: Key words Breast neoplasms ; Malignant myoepithelioma ; Metastasis ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  A breast tumor in a 52-year-old female was interpreted as a malignant myoepithelioma based on morphological and immunohistochemical studies. The tumor consisted of elongated cells with clear cytoplasm and lacked glandular components. The tumor cells were stained positively for keratin, S-100 protein, glial fibrillary acidic protein (GFAP) and muscle-specific actin. Distant metastasis in the right jaw developed 8 years after the initial surgery and the metastatic deposit showed a similar morphology and immunoreactivity. Myoepithelial tumors are generally considered as benign or low-grade lesions and distant metastasis has been rarely documented. The present case presents the possibility of delayed occurrence of distant metastasis in myoepithelial tumor of the breast.
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  • 26
    ISSN: 1432-2307
    Keywords: Key words p21 ; p53 ; Colon ; Immunohistochemistry ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  The WAF1/CIP1 gene product, p21, an inhibitor of cyclin-dependent kinases, is a critical downstream effector in the p53 pathway. The expression of p21 in human neoplasms is heterogeneous, and may be related to p53 functional status. We evaluated p21 immunoreactivity in 103 colorectal carcinomas (CC) in relation to the p53 gene and protein alterations and clinico-pathologic parameters. High p21 expression (more than 10% reactive cells) was seen in 39% of cases. p21 staining was heterogeneous and often detected in clusters of tumour cells; in some tumours p21 staining was more pronounced in superficial areas. No relation was seen between p21 immunoreactivity and site of the tumours (right vs left), TNM stage and grade. p21 expression was related to p53 status as evaluated with IHC or with SSCP analyses, low p21 expression usually being associated with p53 protein overexpression (P=0.048) and p53 gene alteration (P=0.005). The strongest associations were seen when the combined p53/p21 immunophenotype was compared with p53 gene alterations (P=0.0002). These data support the hypothesis that p21 expression in CC is mainly related to p53 functional status, suggesting that p21 expression could be an interesting adjunct in the evaluation of the functional status of the p53 pathway in CC.
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  • 27
    ISSN: 1432-2307
    Keywords: Key words Hypopharynx carcinoma ; Prognosis ; Proliferation ; Ki-S11 ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  As a potential prognostic factor, the proliferative activity of 131 squamous cell carcinomas (SCC) of the hypopharynx and 47 of their cervical lymph-node metastases was analyzed retrospectively by means of monoclonal antibody Ki-S11 immunostaining, which specifically detects the Ki-67 antigen on paraffin-embedded tissue. Median follow-up time was 37.6 months. Ki-S11 revealed distinctive patterns of proliferating cells related to the degree of differentiation. The proliferation fractions in the primaries and their lymph-node metastases did not differ significantly. Patients with high proliferating hypopharynx carcinomas (〉45% labeled cells) had a significantly lower 5-year-survival rate (16%) than patients with low proliferating tumors, whose 5-year-survival rate was 30% (P=0.01). A statistically significant positive correlation was also observed between proliferative activity and lymph-node status (P=0.012). In conclusion, the proliferative activity as determined by means of Ki-S11 immunostaining is of prognostic value with respect to both survival and metastatic risk in SCC of the hypopharynx.
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  • 28
    ISSN: 1432-2307
    Keywords: Key words Mixed ductal-endocrine carcinoma ; Pancreas ; Gastrinoma ; Immunohistochemistry ; Zollinger-Ellison syndrome
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  We report an autopsy case of mixed ductal-endocrine carcinoma of the pancreas presenting as gastrinoma with Zollinger-Ellison syndrome. A 38-year-old Japanese male was found to have Zollinger-Ellison syndrome and pancreatic gastrinoma, and gastrectomy and resection of the pancreatic tumor were performed. However, hypergastrinemia persisted, and the patient died of disseminated carcinomatosis at 62 years of age, 24 years after the onset of Zollinger-Ellison syndrome. At autopsy, the main tumor was present in the residual pancreas, and metastases were noted in many organs. In the pancreas and other organs, ductal and endocrine carcinoma areas were mixed and there was a gradual transition between the two. No acinar differentiation was noted. The ductal elements were positive for mucins and carcinoembryonic antigen but negative for neuroendocrine markers, while endocrine elements were positive for chromogranin A and synaptophysin and to a lesser extent for gastrin, but negative for mucins and carcinoembryonic antigen. The ductal elements comprised about 30% of the tumor cells, and endocrine elements 70%. According to the revised World Health Organization classification, our case was diagnosed as mixed ductal-endocrine carcinoma. Our case is rare because the tumor manifested as gastrinoma with Zollinger-Ellison syndrome and the patient survived for 24 years. To the best of our knowledge, no such case has been reported. Our case suggests that pancreatic endocrine tumors may evolve into mixed ductal-endocrine carcinomas.
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  • 29
    ISSN: 1432-2307
    Keywords: Key words Cyclin B1 ; Esophageal squamous cell carcinoma ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  Recent studies have identified a family of proteins referred to as cyclins, which control the cell cycle. Cyclin B1 activates cdc2, which regulates cell progression through the G2 and M phases. The main aim of this study was to examine the relationships between the cyclin B1 expression in human esophageal squamous cell carcinoma (SCC) and clinicopathological factors and prognosis of the patients. Eighty-seven cases of primary human SCC consecutively obtained at esophagectomy were immunohistochemically studied using an anti-human cyclin B1 protein antibody (2H1-H6). The relationship between cyclin B1 expression and clinicopathological factors, including prognosis, were also statistically assessed. Positive immunostaining of cancer cells, mainly in the cytoplasm, was detected in 72.4% (63/87): heterogeneous pattern in 37.9 % (33/87) and homogeneous pattern in 34.5% (30/87). The prevalence of cyclin B1 expression was significantly higher in cases with invasion deeper than the muscularis propria (P〈0.005) and with venous invasion (P〈0.01) than in other cases. Patients whose SCCs expressed high levels of cyclin B1 protein had a significantly poorer prognosis than did the other patients (P〈0.05). Multivariate analysis demonstrated that cyclin B1 status was an important factor affecting survival (P〈0.05). These findings demonstrated that overexpression of cyclin B1 protein is associated with tumor behavior and prognosis for patients with human esophageal SCC.
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  • 30
    ISSN: 1432-2307
    Keywords: Key words Ductal carcinoma in situ ; Immunohistochemistry ; Myoepithelial cells ; Basal lamina ; Smooth muscle actin ; Calponin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  A retrospective study was made of 38 selected brest tumours with a poorly differentiated in situ duct component. These were classified on haematoxylin and eosin (H&E) as ductal carcinoma in situ (DCIS; 10 cases), DCIS with invasion (17 cases) and DCIS with features suggestive of for stromal invasion (11 cases). The last were these lesions composed of neoplastic ducts with irregular outlines and a myoepithelial layer that was not clearly evident or large neoplastic ducts growing close together or surrounded by inflammatory desmoplastic stroma. Cases of DCIS involving areas of sclerosing adenosis were included in this category. Consecutive sections obtained from each case were studied with a panel of antibodies against myoepithelial cells (alpha smooth muscle actin and calponin) and basal lamina (BL) components (laminin and type IV collagen). It was found that in situ lesions showed well-formed basal lamina and/or an evident myoepithelial layer. These features were lacking in the invasive areas. Nine of the 11 cases with suggestive features of stromal invasion were reclassified as invasive duct carcinoma (5 cases)and DCIS (4 cases), according to the absence or presence of a continuous myoepithelial layer and/or basal lamina. In 2 such cases immunohistochemistry yielded equivocal results and the label ”suggestive of invasion” was therefore pertinent. Immunohistochemistry facilitates the diagnosis of breast DCIS; myoepithelial and basal lamina markers are useful in differentiating microinvasive from in situ ductal carcinomas of the breast.
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  • 31
    ISSN: 1432-2307
    Keywords: Key words Carbohydrates ; N-Sulfation ; O-Sulfation ; Immunohistochemistry ; Rapidly progressive glomerulonephritis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  Crescentic glomerulonephritis leads to a rapid loss of renal function. Although glomerular crescents are rich in extracellular matrix (ECM), the composition and genesis of the ECM are incompletely understood. Heparan sulfate (HS) is a major ECM molecule and has polymeric structure of great variability. Recent findings that alterations in HS epitopes are associated with renal pathology prompted us to hypothesize that specific HS epitopes might be expressed in the evolution of crescents. We reviewed clinical records of 724 patients who underwent renal biopsy and found 21 patients with rapidly progressive glomerulonephritis. Immunohistochemistry was performed using monoclonal antibodies (mAbs) against well-defined HS epitopes. One mAb was directed against unsaturated uronic acid residues generated during the selective removal of HS by heparitinase (a), and a further two different mAbs against N-sulfate-enriched and O-sulfate-poor portions of HS (b). Results showed that mAb (a) reacted to ECM of normal, sclerosed and crescentic glomeruli and that mAbs (b) reacted strongly to ECM of fibrocellular crescents but not to fibrous crescents, the periglomerular areas and noncrescentic intraglomerular areas. We concluded there are regional differences in HS epitope expression, although HS are ubiquitous components of glomerular ECM. N-sulfate-enriched and O-sulfate-poor portions of HS might play a role in crescent formation.
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  • 32
    ISSN: 1432-2307
    Keywords: Key words Autonomic nerve tumour ; Small intestine ; Immunohistochemistry ; Quick-freezing ; Deep-etching
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  A case of gastrointestinal autonomic nerve tumour with skeinoid fibres (SFs) of the jejunum in a 79-year-old Japanese man, was examined by the quick-freezing and deep-etching (QF-DE) method. The tumour consisted of spindle cells with immunohistochemical reactions for vimentin, NSE and CD34. Electron microscopically, features of the neural cells of the myenteric plexus were observed. The QF-DE method demonstrated intercellular meshwork structures, consisting of thin filaments (7–15 nm), with granular deposits. Fully developed parts of the deposits formed nodular aggregates composed of irregularly surfaced thick fibrils (30–48 nm) with a tendency to linear arrangement (SFs). We detected many interconnecting thin filaments (ICTFs) between the SFs, which were pre-existing components in the meshwork, avoiding the granular deposits. The focal thickening formed by the connection between SFs and ICTFs revealed a periodicity typical of SFs (33–45 nm). We conclude that SFs are formed by decoration of the granular deposits along pre-existing intercellular meshwork structures.
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  • 33
    ISSN: 1432-2307
    Keywords: Key words Activin A ; Inhibin A ; Endocrine tumors ; Digestive system ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  Activin A and inhibin A, first isolated from the ovary, are dimeric proteins able to modulate pituitary FSH secretion. Inhibin A is a heterodimer composed of one α-subunit and one βA-subunit (α-βA), while activin A is a homodimer of the βA-subunit (βA-βA). Their identification in several tissues has suggested that they have numerous physiological functions, acting as either paracrine or autocrine factors. The aim of this study was to evaluate the expression of activin A and inhibin A in normal endocrine cells and in 70 endocrine tumours from different sites in the gastro-entero-pancreatic system, using specific monoclonal antibodies directed against the α- and βA-subunits of inhibin/activin. Immunoreactivity for the βA-subunit, but not for the α-subunit, was observed in normal G, EC, and GIP cells of the antrum and duodenum, and in pancreatic A cells. βA-subunit expression was observed in G cell and A cell tumours, and in a few insulinomas and ileal EC cell carcinoids. The α-subunit was found in rare cells in 7 of the 70 tumours and was colocalized with the βA-subunit in only 1 tumor. Specific types of endocrine cells from the gut and pancreas appear to produce only activin A, a possible paracrine or autocrine modulator. Activin A is mainly produced by tumours derived from endocrine cells that normally express it.
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  • 34
    ISSN: 1432-2307
    Keywords: Key words Salivary gland ; Pleomorphic adenoma ; Collagen ; Cell culture ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  The morphogenesis of salivary gland pleomorphic adenoma was examined in vitro using three-dimensional (3-D) collagen gel culture. Pleomorphic adenoma cells were isolated from three parotid gland tumours and cultured as monolayers, after which they were subcultured in floating-collagen gel sandwiches. Cells cultured in both conditions were immunohistochemically characterized and compared using antibodies against various proteins representative of each histological component of salivary glands. Monolayers had myoepithelial characteristics, being positive for vimentin and α-smooth muscle actin. In collagen gels, however, the cells assembled in epithelial nests, showing an architecture similar to that of pleomorphic adenoma. The nests were composed of duct-lining epithelial cells that were positive for epithelial markers, surrounded by myoepithelial cells. Collagen gel culture induces multi-directional differentiation of adenoma cells, suggesting that pleomorphic adenomas originate from stem or reserve cells.
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  • 35
    ISSN: 1432-2307
    Keywords: Key words Systemic granulomatous arteritis ; Epstein-Barr virus ; Virus-associated haemophagocytic syndrome ; In situ hybridization ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  A 61-year-old woman initially presented with symptoms and findings reminiscent of infectious mononucleosis, and her illness then took a rapidly fatal course. Autopsy revealed widespread granulomatous arteritis, with multinucleated giant cells but without eosinophils and fibrinoid necrosis, affecting small arteries and arterioles and infiltration of haemophagocytic histiocytes into many organs. In situ hybridization with Epstein-Barr virus (EBV)-specific oligonucleotide probes showed positive signals in the infiltrating immune cells and epithelial and endothelial cells of the affected organs. EBV-associated haemophagocytic syndrome (EBV-AHS) with systemic granulomatous arteritis was diagnosed. From the immunophenotypes of the infiltrating immune cells, a possible role of CD4+ T-cells in the pathogenesis of this haemophagocytic syndrome and granulomatous vasculitis was suggested.
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  • 36
    ISSN: 1432-2307
    Keywords: Key words Epithelial myoepithelial carcinoma ; Salivary gland tumours ; Immunohistochemistry ; Flow cytometry ; MIB-1 (Ki 67) ; Proliferative markers
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  Three cases of epithelial-myoepithelial carcinoma (EMC) with coexisting areas of high grade carcinoma are reported. In two of the cases there was a previous recurrence, and in all three patients there had been a sudden increase in size before final surgery. The typical ductal and myoepithelial components of EMC showed the usual biphasic pattern and the expected immunophenotypes, with expression of wide spectrum cytokeratins, Cam 5.2 and EMA in the ductal part, and muscle-specific actin, smooth muscle actin, S-100 protein, vimentin and cytokeratins in the myoepithelial component. These areas also had a low mitotic count and low proliferation rate as measured by immunohistochemistry and by flow cytometry. Conversely, areas of high-grade tumour had the features of a large cell carcinoma, with focal mucin secretion in two cases. This high-grade component showed an epithelial immunophenotype in two cases, and was negative for all tested markers in the third one. The mitotic counts and the proliferation rates were much higher in these anaplastic areas. One of the patients died 3 months after treatment; another developed lymph node metastases 1 year later and was alive after 6 years of follow-up. The third patient was alive without evidence of disease 7 months after wide surgical resection of the tumour. The possibility of anaplastic transformation in EMC makes thorough sampling mandatory in this type of neoplasm.
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  • 37
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 434 (1999), S. 551-560 
    ISSN: 1432-2307
    Keywords: Key words Systemic amyloidosis ; Brain ; Circumventricular organs ; Choroid plexus ; Immunohistochemistry ; Aβ colocalization.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  Amyloid deposits in cerebral vessels are common in β-amyloid diseases (Alzheimer’s disease, congophilic amyloid angiopathy, Down’s syndrome and hereditary cerebral amyloidosis with haemorrhage of the Dutch type). We report of 20 autopsies on patients who had died with systemic amyloidosis of the AA, Aλ and Aκ types: the brains were examined for the occurrence of amyloid. Vascular amyloid was detected in choroid plexus (in 17 of 20 cases), infundibulum (5 of 8), area postrema (6 of 11), pineal body (3 of 7) and subfornical organ (2 of 3), but not in cortical and leptomeningeal vessels. Immunohistochemical classification of the cerebral amyloid and the systemic amyloid syndrome showed identity proving the same origin of both. The distribution is indicative of a haematogenic pattern of amyloid deposition in systemic amyloidosis and is different from that in Alzheimer’s, prion, ATTR and cystatin C diseases. It corresponds to areas of the brain with a ”leaky” blood–brain barrier. Additionally, all the cases with AA amyloidosis exhibited an Aβ coreactivity in choroid plexus vessels. In one exceptional case, Aβ reactivity of AA amyloid also occurred outside of the brain.
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  • 38
    ISSN: 1432-2307
    Keywords: Key words E-cadherin ; Colorectal cancer ; Immunohistochemistry ; Mutation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  E-cadherin, a transmembrane cell adhesion molecule, has been observed to have an altered pattern of immunoreactivity in several types of carcinomas. In lobular breast cancer, loss of immunoreactivity has been shown to be due either to out-of-frame deletions or to nonsense mutations of the E-cadherin gene. We analysed 29 cases of completely resected colon carcinoma with immunohistochemistry using the HEC-D1 antibody. Normal protein expression similar to that in the adjacent nonmalignant mucosa was seen in 6 cases, whereas 23 tumours had reduced or absent E-cadherin expression. In the 8 cases with no expression of E-cadherin revealed by immunohistochemistry, the entire E-cadherin cDNA sequence was analysed. In these cases, sequence analysis failed to reveal any cDNA mutations despite the negative immunohistochemistry. Possible explanations for this discrepancy include regulatory defects in the E-cadherin promoter, abnormalities at the translation or protein processing levels and mutations in other parts of the gene that were not investigated by the cDNA analysis (e.g. intronic sequences), which could play a role in causing abnormal processing of the E-cadherin protein.
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  • 39
    ISSN: 1434-0879
    Keywords: Key words Galectin-1 ; Galectin-3 ; Human prostate ; cancer ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Galectin-1 and galectin-3, two β-galactoside-binding proteins, have been suggested to play a role in the development and progression of cancer. We have studied the expression of these molecules in normal human prostate tissue and prostate adenocarcinoma. Immunohistochemistry was used to examine formalin-fixed, paraffin-embedded sections of seven normal human prostates, eight cases of prostatic intraepithelial neoplasia (PIN), 20 primary adenocarcinomas of the prostate, and 12 prostate cancer metastases. Galectin-1 was expressed in most cases of all four histologic types. In contrast, galectin-3 expression was significantly decreased in primary carcinoma and metastatic disease compared with normal and premalignant tissue. Galectin-3 expression in primary tumors tended to be less than that of surrounding normal glands. We conclude that loss of galectin-3 expression may be associated with the progression of prostate cancer.
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  • 40
    Electronic Resource
    Electronic Resource
    Springer
    Urological research 27 (1999), S. 103-107 
    ISSN: 1434-0879
    Keywords: Key wordsnm23 ; Immunohistochemistry ; Renal cell carcinoma ; Flow cytometry ; Survival
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract In many tumors an expression of nm23 gene products is associated with a lower metastatic potential. The aim was to evaluate whether nm23 gene expression in renal cell carcinoma was associated with clinicopathological findings and survival. In 41 patients, the expression of nm23 protein was analyzed in tumor and corresponding kidney cortex tissue by immunohistochemical analysis using a monoclonal nm23-H1 antibody. In all kidney cortex samples intense nm23 staining was found. Of 41 tumors, 15 had high, 12 intermediate, 5 low nm23 expression whereas 9 tumors showed none. There were no differences in nm23 staining between different stages, grades or size of tumor. No correlation between survival and nm23 expression was observed. However, diploid tumors had significantly less nm23 staining compared with aneuploid tumors, indicating that nm23 gene inactivation might be a favorable sign. The expression of nm23 gene products seems not to be correlated to tumor progression and metastatic ability in renal cell carcinoma.
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  • 41
    ISSN: 1434-0879
    Keywords: Key words Alpha-1-microglobulin ; Calcium oxalate ; Crystallization ; ELISA ; Human ; Urine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract In the past few years, alpha-1-microglobulin (α1m) has been copurified from human urine with bikunin, a potent inhibitor of calcium oxalate (CaOx) crystallization in vitro. In this study, we have purified α1m without bikunin contamination and investigated its possible role in CaOx crystallization by in vitro and in vivo studies. Alpha-1m was purified with an anti-α1m antibodies CNBr-activated sepharose column. Two molecular species of α1m of respectively 30 and 60 kDa were purified. For each protein, two blots of 30 and 60 kDa cross-reacted with anti-α1m antibodies, suggesting that these two forms were derived one from the other. Both protein species inhibited CaOx crystallization in a dose-dependent manner in two in vitro tests. In the first test, the presence of α1m of 30 kDa (8 μg/ml) in a medium containing 0.76 mM CaCl2 (with 45Ca) and 0.76 mM Ox(NH4)2 inhibited CaOx crystallization by 38% as estimated by supernatant radioactivity after 1 h of agitation. In the second test, CaOx kinetics were examined for 3 to 10 min in a turbidimetric model at 620 nm. The presence of α1m of 30 kDa in a medium containing 4 mM CaCl2 and 0.5 mM Na2Ox inhibited CaOx crystallization by 41.5%, as estimated by the slope modification of turbidimetric curve. Alpha-1m can be considered as another inhibitor of urinary CaOx crystal formation, as shown by the present in vitro studies. Using an ELISA assay, we found that urinary α1m concentration was significantly lower in 31 CaOx stone formers than in 18 healthy subjects (2.95 ± 0.29 vs 5.34 ± 1.08 mg/l respectively, P = 0.01). The decreased concentration of α1m in CaOx stone formers could be responsible in these patients, at least in part, for an increased risk of CaOx crystalluria.
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  • 42
    ISSN: 1432-0533
    Keywords: Key words Amyotrophic lateral sclerosis ; Bunina body ; Guam ; Immunohistochemistry ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract An investigation of Bunina bodies is important when studying the pathoetiology and pathomechanisms involved in amyotrophic lateral sclerosis (ALS). It may serve as a clue essential for the study of the pathogenesis of Guamanian amyotrophic lateral sclerosis (ALS-G), and it may provide a means of answering the question of whether ALS-G is the same disease as classical ALS or a different entity. In ALS-G, however, no precise histochemical, immunohistochemical, or detailed ultrastructural examination has been published to date. To elucidate the pathological differences/similarities of Bunina bodies between classical ALS and ALS-G, we performed histochemical, immunohistochemical, topographic and ultrastructural examinations. Histochemically, hematoxylin and eosin, Masson’s trichrome, methylgreen-pyronin, phosphotungstic acid-hematoxylin, Klüver-Barrera, Bodian and periodic acid-Schiff staining were utilized. Immunohistochemical examination was performed using antibodies for cystatin C, ubiquitin, Tau-2, Cu/Zn superoxide dismutase, phosphorylated neurofilament and glial fibrillary acidic protein. Histochemical findings were consistent with those previously described for classical ALS. The immunohistochemical study showed that in ALS-G Bunina bodies were intensely labeled by an anti-cystatin C antibody. Topographic examination demonstrated that Bunina bodies were distributed in the spinal anterior horns and Clarke’s column in the spinal cord. Ultrastructurally, Bunina bodies were composed of electron-dense amorphous/ granular material accompanied by vesicular structures and neurofilaments. The results of the present study have revealed that the pathological features of Bunina bodies in ALS-G are identical to those seen in classical ALS. These findings strongly suggest that a similar degenerative process occurs in the spinal anterior horn cells in both ALS-G and classical ALS.
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  • 43
    ISSN: 1432-0533
    Keywords: Key words Cytoskeletal proteins ; Immunohistochemistry ; Myofibrillar myopathy ; Hereditary myopathy ; Holstein-Friesian cattle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We have investigated the expression, using immunohistochemical and Western blot methods, of some cytoskeletal proteins including desmin, vimentin, actin, α-actinin, and ubiquitin in hereditary myopathy of the diaphragmatic muscles in Holstein-Friesian cattle (the histochemical and electron microscopical aspects have been previously reported). Immunohistochemically, the expression of desmin was observed strongly in the subsarcolemmal regions, but was lacking or faint in the area corresponding to the core-like structures. Vimentin showed almost the same localization as desmin, but no activity could be observed in the core-like structures. In addition, the core-like structures showed strong immunoreactivity for actin and ubiquitin, but no immunoreactivity for α-actinin. F-actin stained with phalloidin-tetramethyl-rhodamine was strongly positive in irregular spots that corresponded to the core-like structures, but was negative for desmin-positive regions. Western blot analysis of the diseased muscles revealed a significant increase in the amount of desmin and vimentin immunoreactivities and similar amounts of actin and α-actinin compared with the control muscles. Two-dimensional electrophoresis revealed no isoforms of desmin, suggesting the absence of abnormal phosphorylated forms of desmin. Since the co-localization of desmin and vimentin and the absence of phosphorylated desmin suggest that the overexpression of desmin may be reflected in the reactive change or regenerating process, the present myopathy should be regarded as an entity separate from desmin-storage myopathy or desmin-related myopathies. We also discuss the possibility that the present myopathy could be considered as myofibrillar myopathy, a recently proposed nosological entity.
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  • 44
    ISSN: 1432-0533
    Keywords: Key words Serotonin ; Thiamine deficiency ; Immunohistochemistry ; Vulnerability ; Degeneration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We examined changes in 5-hydroxytriptamine (5-HT, serotonin) neurons in pyrithiamine-induced thiamine deficiency in mice immunohistochemically. Extensive decreases in the densities of 5-HT-immunoreactive fibers were detected in the lateral septal nucleus, the thalamus, the medial mammillary nucleus, the dorsal and the median raphe nuclei, the raphe obscurus nucleus, the tegmental area, the cerebellum and the vestibular nucleus, though only a small decrease was detected in the inferior colliculus. Most remarkably, degenerative winding fibers were detected between the deep mesencephalic nucleus and the ventral tegmental area. Increases in intensity of 5-HT immunoreactivity in the dorsal raphe nucleus and decreases in the number of 5-HT-immunoreactive cell bodies in the dorsal and the median raphe nuclei were detected. These results demonstrated the differential vulnerability of 5-HT neurons in thiamine-deficient mice. This is the first report to demonstrate changes in 5-HT neurons immunohistochemically throughout the brain of pyrithiamine-induced thiamine deficient mouse.
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  • 45
    ISSN: 1432-0568
    Keywords: Key words Fish ; Pituitary gland ; Developmental biology ; Cell differentiation ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  We previously reported the chronological appearance of adenohypophysial cells in freshwater teleosts using an immunocytochemical technique. The present study investigated the chronological appearance of adenohypophysial cells in the ayu, which is spawned and has its early development in brackish water, and the results were compared with those obtained in freshwater and seawater teleosts, as well as in other vertebrates. In the adult teleostean adenohypophysis, seven or eight types of secretory cells have been distinguished, each of which produce different hormones: prolactin (PRL), growth hormone (GH), thyroid stimulating hormone (TSH), gonadotropic hormones (GTH I and GTH II), adrenocorticotropic hormone (ACTH), melanophore stimulating hormone (MSH) and somatolactin (SL). In the pituitary of adult ayu, seven distinct types of glandular cells (PRL, GH, TSH, GTH, ACTH, MSH and SL cells) were identified. Chronologically, a few immunoreactive (ir)-PRL and ir-GH cells appeared in the ventral side of the pituitary one day before hatching. Then, just after hatching, ir-GTH cells were observed in the central to dorsal portion; ir-ACTH cells were found distributed in the anterior portion and some ir-MSH and a few ir-SL cells were seen in the posterior portion of the pituitary. Finally, a small number of ir-TSH cells were identified 50 days after hatching. These results differed from those obtained in other fishes previously reported with regard to the times of appearance of the PRL and GH cells. PRL cells appeared first, followed by GH cells in the freshwater teleosts, PRL and GH cells appeared at the same time in the brackishwater teleosts, while GH cells appeared first and PRL cells appeared last in the seawater teleosts. These results reflect the fact that PRL plays a major role in osmoregulation among freshwater teleosts, as compared with GH, which plays a similar role in seawater teleosts. It seems that both PRL and GH may play important roles in osmoregulation in brackishwater fish.
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  • 46
    ISSN: 1432-0568
    Keywords: Key words Autonomic ; Wholemounts ; Immunohistochemistry ; Myenteric ganglia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  Nitrergic (NO) neurons play crucial inhibitory roles in the control of gut motility. Variations in the density of these neurons within the gastrointestinal tract (GI) may provide useful functional information, but, most surveys available have employed limited and/or highly localized samples. It remains unclear to what extent (a) NO neurons are concentrated disproportionately in particular GI regions, or (b) variations in NO cell number merely reflect changes in overall myenteric neuron density. This experiment surveyed the distributions of neuronal nitric oxide synthase-positive (NOS+) and other myenteric neurons in the GI tract, using immunohistochemical and Cuprolinic blue counterstaining techniques. Adjustable sampling grids superimposed on wholemounts were used to investigate the topographic patterns in the stomach (90 sampling sites; 45 per side) and proximal duodenum (63 loci). We present four major findings: First, variations were detected in the number of NOS+ neurons in specific regions of the stomach (e.g., corpus〉antrum@forestomach) and along both longitudinal (oral〉anal) and circumferential (mesenteric〉antimesenteric) axes in the duodenum. Second, the variations in NOS+ neuronal counts within each organ covaried with the total number of myenteric neurons at different locations (stomach, r=0.77; duodenum, r=0.59), suggesting that local myenteric plexus density is a factor determining NOS+ cell concentrations. Third, in contrast to such a principle of covariation within each organ, NOS+ neurons constituted a consistently smaller proportion of gastric (20%) than of duodenal (28%) myenteric plexus neurons, suggesting that a second principle controls the characteristic percentages of the myenteric plexus that express NOS in different organs. Fourth, the regional samples were used to extrapolate the overall number of NOS+ and total myenteric cells in the rat stomach (43,000; 217,000) and first 3.5 cm of the small intestine (29,000; 103,000). These results, taken together, also suggest that the surveying protocol used is capable of detecting subtle differences in cellular distributions, thus providing a practical strategy for investigating patterns of chemical phenotypes within the GI tract.
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  • 47
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    Anatomy and embryology 199 (1999), S. 45-56 
    ISSN: 1432-0568
    Keywords: Key words Skin ; Proteoglycan ; Development ; Human ; Fetal
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  The extracellular matrix of human fetal skin differs substantially from that of adult skin. Fetal skin contains sparse amounts of fibrillar collagen enmeshed in a highly hydrated amorphous matrix composed of hyaluronan and sulfated proteoglycans. Both fetal and adult skin contain two major interstitial proteoglycans that are extracted by chaotrophic agents and detergents. These are the large chondroitin sulfate proteoglycan versican and the small dermatan sulfate proteoglycan decorin. For this study, proteoglycans extracted from fetal and adult skin were compared on Western blots to determine the relative amounts of versican. Decorin present in the same samples provided an internal standard for these studies. Fetal skin differed from adult skin in that it contained a significantly higher proportion of versican than did adult skin. Immunohistochemical studies compared early-fetal with mid-fetal skin and found that versican was a significant component of the interstitial extracellular matrix at both of these stages of skin development. However, by the mid-fetal period, interstitial versican became restricted to the upper half of the dermis, although versican also continued to be highly expressed around hair follicles, glands, and vasculature in the lower half of the dermis. Fetal skin extracts differed from an adult skin extract by the presence of a 66-kDa protein immunologically related to versican and by the absence of a 17-kDa core protein of a proteoglycan related to decorin. Both of these molecular species may represent degradation products of their respective proteoglycans. Monoclonal antibodies which detect epitopes in native chondroitin sulfate glycosaminoglycan chains recognized versican extracted from fetal skin. However, the tissue distribution of these antigens did not entirely conform to that for versican core protein, suggesting that versican in different regions of the skin may be substituted with glycosaminoglycan chains with different microchemistries. The results of these studies indicate that human fetal skin is structurally different from adult skin in terms of both the distribution and the composition of the large, aggregating chondroitin sulfate proteoglycan versican.
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  • 48
    ISSN: 1432-0533
    Keywords: Key words Amantadine ; Human ; N-methyl-d-aspartate ; Phencyclidine ; Postmortem brain
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Low doses of N-methyl-d-aspartate (NMDA)-type glutamate receptor antagonists induce morphological alterations in neurons of the cingulate gyrus and retrosplenial cortex of the rat. Neuronal cell death may result at higher doses. These effects are a major concern with regard to the introduction of new NMDA receptor antagonists into clinical trials. Amantadine is an uncompetitive NMDA receptor antagonist, which has been in clinical use for many years. In the present study we have looked for possible morphological alterations like necrosis in postmortem human brain tissue of patients previously treated with amantadine. Formalin-fixed tissue samples were taken from the hippocampus, cingulate gyrus, and retrosplenial cortex of 8 patients on previous amantadine medication and of 11 controls. Histopathological examination of sections was performed blind. All brains except one revealed either nonspecific age-related or cerebrovascular changes or other neurodegenerative disorders including Alzheimer’s, Parkinson’s or Lewy body disease. In conclusion, histopathological examination of the hippocampus, retrosplenial cortex, and cingulate gyrus of human brain did not reveal changes suggested to be specific for previous amantadine treatment.
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  • 49
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    Acta neuropathologica 97 (1999), S. 40-44 
    ISSN: 1432-0533
    Keywords: Key words Pituitary gland ; Immunohistochemistry ; Mitochondria ; Oncocytes ; Oncocytomas
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Immunocytochemical examination for mitochondrial protein and cytochrome oxidase was performed to demonstrate oncocytes in normal adenohypophysis obtained from 28 patients of various age. A small number of solitary large epithelial cells showed intense cytoplasmic granular immunoreactivities for mitochondrial protein and cytochrome oxidase. The proportions of the cells positive for the former and the latter ranged from 0% to 5.9% (mean ± SD; 1.5 ± 1.7%) and from 0% to 4.9% (1.4 ± 1.6%), respectively. These cells were either absent or extremely rare in young patients (under 10 years) but tended to increase in number with age (P 〈 0.0001). On the other hand, the mirror section technique showed that most of these cells were negative for adenohypophysial hormones, but a few of them were faintly positive for: α-subunit (8.0%), β-subunits of follicle-stimulating hormone (4.8%), luteinizing hormone (2.5%), thyroid-stimulating hormone (1.0%), and growth hormone (0.5%), and were negative for prolactin and adrenocorticotropic hormone. We considered that these cells represent oncocytes that exist in varying numbers in normal adenohypophysis. It was suggested that oncocytes in normal adenohypophysis share various common features with tumorous oncocytes of pituitary oncocytomas.
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  • 50
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    Acta neuropathologica 98 (1999), S. 407-413 
    ISSN: 1432-0533
    Keywords: Key words Hemimegalencephaly ; Tuberous sclerosis ; Large neurons ; Balloon cells ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Hemimegalencephaly, an uncommon sporadic nonfamilial congenital dysplastic abnormality of the central nervous system, constitutes a pathological spectrum of neuronal migration disorders, but consistently includes abnormal large neurons similar to those in the cortical tubers of tuberous sclerosis. Microscopically, there are also cells with homogeneous and weakly eosinophilic cytoplasm with a single eccentric nucleus, sometimes called balloon cells (likewise prominent in tuberous sclerosis). We looked for immunohistochemical and ultrastructural differences in the large neurons and balloon cells between hemimegalencephaly and tuberous sclerosis. Microtubule-associated protein 1B and 2, phosphorylated and non-phosphorylated neurofilament and synaptophysin identify the large neurons and distinguish them from balloon cells in both entities. Balloon cells in hemimegalencephaly showed no immunoreactivity for TSC2 gene product, tuberin, and vimentin, but similar cells in tuber tissue showed consistent immunoreactivity. Balloon cells in hemimegalencephaly showed no immunoreactivity for glial fibrillary acidic protein, but some cells in tubers showed such immunoreactivity. Ultrastructurally, balloon cells in hemimegalencephaly contained very few lysosomes, microfilaments, and microtubules, but abundant lipofuscin granules. Similar cells in tubers had prominent lysosomes, more microfilaments and microtubules, and very few lipofuscin granules. The resemblance between abnormal cells in hemimegalencephaly and tuberous sclerosis is superficial; their immunohistochemistry and electron microscopic profiles show distinct differences.
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  • 51
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    Acta neuropathologica 97 (1999), S. 215-220 
    ISSN: 1432-0533
    Keywords: Key words Cerebral ischemia ; Inflammation ; Immunohistochemistry ; Nitrotyrosine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The inducible or “immunological” isoform of nitric oxide synthase (iNOS) is induced in many cell types by inflammatory stimuli and synthesizes toxic amounts of NO. In rodent models of focal cerebral ischemia, iNOS is expressed in neutrophils invading the injured brain and in local blood vessels. Studies with iNOS inhibitors and iNOS null mice indicate that NO produced by iNOS contributes to ischemic brain injury. In the present study, we sought to determine whether iNOS is also expressed in the human brain after ischemic stroke. Studies were conducted using immunohistochemistry on autopsy brains with neuropathological evidence of acute cerebral infarction. iNOS immunoreactivity was observed in neutrophils infiltrating the ischemic brain and in blood vessels within the ischemic territory. iNOS-positive cells also were immunoreactive for nitrotyrosine, reflecting protein nitration by NO-derived peroxynitrite and nitrites. iNOS or nitrotyrosine immunoreactivity was not detected outside the region of the infarct. These observations provide evidence that iNOS is expressed in the human brain after ischemic infarction and support the hypothesis that iNOS inhibitors may be useful in the treatment of ischemic stroke in humans.
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  • 52
    ISSN: 1432-0533
    Keywords: Key words Amyotrophic lateral sclerosis ; Advanced glycation endproducts ; Immunohistochemistry ; Superoxide dismutase ; Hyaline inclusions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract To determine the role of advanced glycation endproducts (AGE) in the pathogenesis of familial amyotrophic lateral sclerosis (ALS) with superoxide dismutase-1 (SOD1) mutation, we investigated the immunohistochemical localization of N ɛ-carboxymethyl-lysine (CML), one of the major AGE structures, in spinal cords from three familial ALS patients with a heterozygous Ala to Val substitution at codon 4 in the gene for SOD1. Neuronal hyaline inclusions (NHIs), the abnormal structures seen in some of the remaining lower motor neurons of familial ALS patients with SOD1 mutation, were intensely stained by a monoclonal antibody specific for CML in contrast to the only weakly stained cytoplasm. Immunoelectron microscopy depicted the CML determinants restricted to the granule-associated thick linear structures that mainly compose the NHIs. The NHIs were also recognized by antibodies to SOD1, phosphorylated neurofilament protein and ubiquitin. No focal collection of either CML or SOD1 was found in neurons of the control individuals. Our results indicate that CML is a component of the NHIs of familial ALS patients with SOD1 mutation, and suggest that the CML formation may be mediated by protein glycoxidation or lipid peroxidation in the presence of oxidative stress from mutant SOD1, in association with motor neuron degeneration.
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  • 53
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    Acta neuropathologica 97 (1999), S. 463-468 
    ISSN: 1432-0533
    Keywords: Key words Amyotrophic lateral sclerosis ; β-Amyloid precursor protein ; Immunohistochemistry ; Fast axonal transport ; Anterior horn neuron
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We investigated the localization and extent of β-amyloid precursor protein (β-APP695) immunoreactivity as a sensitive marker for impairment of fast axonal transport in the spinal cords of 21 patients with amyotrophic lateral sclerosis (ALS), paying special attention to anterior horn neurons. Specimens from 18 patients without neurological disease served as controls. Increased β-APP immunoreactivity was frequently recognized in the anterior horns of the ALS patients with short clinical courses or with mild depletion of anterior horn cells, while no β-APP immunoreactivity was demonstrated in those with severe depletion of anterior horn neurons or with long-standing clinical courses. Increased β-APP immunoreactivity in the anterior horn neurons was mainly confined to the perikarya and no immunoreactivity was recognized in the dendrites or proximal axons directly emanating from the somata, except some spheroids (proximal axonal swellings) which showed increased immunoreactivity of β-APP. Increased β-APP immunoreactivity was spotted or focally aggregated in the perikarya of normal-looking large anterior horn neurons, while it was frequently diffuse in that of degenerative neurons such as central chromatolytic cells and or those with simple atrophy. On the other hand, the controls showed no immunostaining with β-APP in the spinal cord. These findings suggest that increased immunoreactivity of β-APP in neuronal perikarya of the anterior horn cells and in some proximal axonal swellings is an early change of ALS, and may be a response of the increased synthesis of β-APP resulting from neuronal damage, or the impairment of fast axonal transport.
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  • 54
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    Acta neuropathologica 98 (1999), S. 197-202 
    ISSN: 1432-0533
    Keywords: Key words Diffuse axonal injury ; Head injury ; β-amyloid precursor protein ; Immunohistochemistry ; Forensic neuropathology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Widespread damage to axons in the white matter of the brain is a well-recognised consequence of non-missile head injury. This diffuse axonal injury is characterised by a gradual swelling of the axon associated with an accumulation of cellular organelles and proteins. We have investigated the relationship between the size of the swellings of the damaged axon with survival time in post-mortem brain tissue. Sixty-six cases of head injury with known length of post-traumatic survival were selected for study, and immunohistochemistry for β-amyloid precursor protein (βAPP) was carried out. The minimum diameter of the βAPP-immunolabelled damaged axons was measured in micrometers using the IBAS image analysis system. There was a strong, positive and significant relationship between the mean size of axonal swelling and survival time which plateaued at around 85 h post injury. With longer survival times the situation becomes more complex. βAPP immunolabelling of damaged axons can contribute evidence about trauma and post-injury survival time in the forensic setting but should always be assessed with other evidence.
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  • 55
    ISSN: 1432-0533
    Keywords: Key words Purkinje cell ; Cerebellum ; Development ; Inositol 1 ; 4 ; 5-triphosphate type 1 receptor ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Immunohistochemical analyses were carried out on the Purkinje cells from 21 autopsied fetal and early postnatal normal cerebella using a monoclonal antibody against the inositol 1, 4, 5-triphosphate type 1 receptor (IP3R1) as a cytochemical marker of Purkinje cells. In normal adult cerebella used as positive controls, the cell bodies, axons, and dendrites, including spiny branchlets of the Purkinje cells, were specifically stained by the antibody. In the fetal cerebella examined, the IP3R1 immunoreactivity was first detected in the soma of multilayered cells just beneath the molecular layer at 16 weeks of gestation. The IP3R1 immunoreactivity gradually increased in area of positive staining from soma to dendrites and spiny branchlets, and the dendritic outgrowth rapidly progressed during 6 months after birth. The Purkinje cell maturation was more advanced in the vermis than in the hemisphere, more in the posterior lobe than in the anterior lobe, and more at the bottom of the folia than at the top. Partial absence of the Purkinje cells in the cerebellar cortex was observed in three cases. Heterotopias including Purkinje cells were often noted in the cerebellar white matter in five cases.
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  • 56
    ISSN: 1432-0533
    Keywords: Key words Glioma ; Cyclooxygenase ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Cyclooxygenases (COX, prostaglandin endoperoxide synthases, PGG/H synthases) are potent mediators of inflammation. While COX-1 is constitutively expressed in a wide range of tissues, COX-2 is cytokine inducible. Although COX-1 expression is observed in normal tissue, enhanced COX-2 expression has been attributed a key role in the development of edema, impeding blood flow and immunomodulation observed in pathologically altered tissues. Here, we have analyzed the expression of COX-1 and COX-2 in 50 gliomas and 10 control brains with no neuropathological alterations by immunohistochemistry; 22 glioblastoma multiforme, 9 anaplastic astrocytomas, 5 protoplasmic astrocytomas, 1 gemistocytic astrocytoma and 13 fibrillary astrocytomas were included in the study. Compared with control brains, accumulation of COX-1 was detected in 20–50% of all cells in both low- and high-grade gliomas. Double-labeling experiments revealed COX-1 expression in subsets of macrophages/ microglial cells within the tumor parenchyma and in areas of infiltrative tumor growth. Of the COX-1-positive cells, 90% expressed MHC class II antigens. No COX-1 immunoreactivity was observed in tumor cells. COX-2-positive cells accumulated in tumor cells and in single macrophages/microglial cells in the immediate vicinity of necroses. Further studies are required to determine whether COX-2 is involved in the development of necrosis or, more likely, whether COX-2 is a part of the tumor tissue response to necrosis.
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  • 57
    ISSN: 1432-0533
    Keywords: Key words Calcium-binding protein ; Enkephalin ; Hypoxic encephalopathy ; Immunohistochemistry ; Marbled state
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We have immunohistochemically analyzed the marbled state in 8 cases of perinatal hypoxic ischemic encephalopathy and 4 cases of infantile hypoxic encephalopathy, using antibodies against calbindin-D28k (CaBD), glial fibrillary acidic protein (GFAP), methionine-enkephalin (MEnk), myelin basic protein (MBP), neurofilament (NF), parvalbumin (PV), substance-P (SuP) and synaptophysin (SP). The marbled state was found in the thalamus in 11 cases, whose age at death was over 10 years. Four cases demonstrated the marbled state in the cerebral cortex, in addition to the striatum and/or the thalamus. The abnormally myelinated fibers in the marbled state were stained with both Klüver-Barrera and Holzer stainings; however, they were partly immunopositive for MBP and completely immunonegative for GFAP, CaBD, MEnk, PV, SuP and SP, although some of the neurons and/or fibers showed immunoreactivities for those calcium-binding proteins and/or neurotransmitters. The axons were visualized in the abnormally myelinated fibers by Bodian staining and/or anti-NF immunostainings in the cerebral cortex and striatum but not in the thalamus. GFAP-positive astrocytes did not show any continuity with the abnormally myelinated fibers. These histological features were seen in the cerebral cortex, striatum and thalamus. Difference of the etiology did not affect the histological features with the exception of anti-PV staining, in which PV-immunopositive neurons were observed only in aged subjects with infantile hypoxic encephalopathy, and seemed to be more severely affected by hypoxic stress during the perinatal period than the early infantile period. These data suggest that the site of lesion or the length of survival period after brain injury might influence the formation of the marbled state rather than the etiology. And the direct relationship between the abnormally myelinated fiber and astrocytic process was not verified.
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  • 58
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    Acta neuropathologica 97 (1999), S. 433-436 
    ISSN: 1432-0533
    Keywords: Key words Congenital nemaline myopathy ; Nebulin ; α-Actinin ; Immunohistochemistry ; Western blot
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Since the nebulin gene is located in the candidate gene locus of autosomal recessive nemaline myopathy, 2q21.2–q22, we examined five muscle biopsy specimens with monoclonal and polyclonal antibodies against nebulin in combination with the modified Gomori trichrome stain. We were able to demonstrate immunohistochemically that there was no abnormality in nebulin in the muscle fibers both with and without nemaline bodies. Although the molecular weight of nebulin was normal, it was slightly reduced in amount on immunoblotting.
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  • 59
    ISSN: 1432-0568
    Keywords: Key words Visual system ; Immunohistochemistry ; In situ hybridization ; PNA ; Tenascin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  In the tree shrew (Tupaia belangeri), the cytoarchitectonic lamination of the lateral geniculate nucleus cannot be detected at birth; it only appears during the early postnatal period. However, a laminated pattern was revealed with rapid Golgi staining and retinal afferents were segregated into the appropriate laminae well before cytoarchitectonic lamination could be seen. Both observations indicate that the extracellular matrix may play a role in the separation of lateral geniculate nucleus cells into laminae. In the present study, the organization of the extracellular matrix was investigated during development using immunohistochemical and in situ hybridization techniques. For immunohistochemistry, peanut agglutinin (PNA) lectin and antibodies against tenascin (TN) were chosen, while for in situ hybridization, mTN riboprobes were used, simultaneously, with antibodies against Vimentin (Vim) and microtubule associated protein (MAP-2). The results showed that the pattern of PNA-binding glycoproteins and that of tenascin were relatively similar, although tenascin appeared later and disappeared earlier. The first interlaminar spaces to be detected were those between layers innervated by opposite eyes. The TN specific mRNA was detected in the lateral geniculate nucleus at P0, but was no longer visible at P7. By comparing TN mRNA and Vim or MAP-2 stainings a correspondence could be observed. The extracellular matrix lamination therefore seems to precede cytoarchitectonic lamination, suggesting that the extracellular matrix may play a role in the development of laminated structures. The TN-producing cells seem to be developing astrocytes and neurons.
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  • 60
    ISSN: 1432-0533
    Keywords: Key words Prostaglandin H2 synthase ; Stroke ; Inflammation ; Immunohistochemistry ; Prostaglandins
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The prostaglandin synthesizing enzyme cyclooxygenase-2 (COX-2) is up-regulated in the brain of rodents during cerebral ischemia and contributes to ischemic brain injury. This study sought to determine whether COX-2 is also up-regulated in the human brain in the acute stages of cerebral ischemic infarction. Paraffin-embedded sections from patients who died 1–2 days following infarction in the middle cerebral artery territory were processed for COX-2 immunohistochemistry. COX-2 immunoreactivity was observed in infiltrating neutrophils, in vascular cells and in neurons located at the border of the infarct. The data suggest that COX-2 up-regulation is also relevant to cerebral ischemia in humans and raise the possibility that COX-2 reaction products participate in the mechanisms of ischemic injury also in the human brain.
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  • 61
    ISSN: 1432-0533
    Keywords: Key words Xp21 muscular dystrophy carriers ; Muscle biopsy ; Immunohistochemistry ; X chromosome ; inactivation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We report two carriers of Xp21 muscular dystrophy with unusual clinical manifestations and striking variability of dystrophin deficiency within the same muscle biopsy. The first patient was a 60-year-old nun with recent onset of cramps and proximal weakness, mimicking an acquired myopathy. Muscle biopsy disclosed slight alterations in one sample and severe dystrophic changes in another; dystrophin was absent in 7% fibers in the former specimen and in 60% in the second. X inactivation was skewed with 90% cells inactivating the same X chromosome. The second patient was a 17-year-old girl with hyperCKemia, learning disability and a family history of X-linked muscular dystrophy. Muscle biopsy displayed slight fiber size variability and some internal nuclei; dystrophin was absent only in one muscle fiber. A second sample with the same morphological features demonstrated dystrophin deficiency with mosaic distribution. The pattern of X inactivation was normal. These cases emphasize the variability of histopathological changes and dystrophin deficiency in Xp21 muscular dystrophy carriers and the risk of sampling errors in muscle biopsy.
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  • 62
    ISSN: 1432-0533
    Keywords: Key words Polyglucosan body ; Periodic ; acid-Schiff-positive granules ; Mouse brain ; Immunohistochemistry ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Periodic acid-Schiff-positive granules (PGs) appear in the mouse brains in relation to advancing age. The exact location and pathophysiological significance of PGs, however, are not fully understood. The incidence, staining properties, and topographical distributions of PGs in the brains of 17 AKR mice ranging in age from 7 to 18 months were examined histochemically and immunohistochemically using antibody KM279 raised against a polyglucosan. In addition, to define the precise site of PG formation, we investigated the brains of 4 AKR mice of 24 months of age using conventional and immunoelectron microscopy. PGs were seen in all mice examined and the levels were increased with age. The PGs were located predominantly in the hippocampus and, to a lesser extent, in the cerebellum and olfactory bulb. Immunohistochemically, PGs in the hippocampus and cerebellum were labeled uniformly with KM279. On immunoelectron microscopy with this monoclonal antibody, the fibrillar or membranous structures corresponding to PGs seen using light microscopy were labeled specifically with gold particles. With conventional electron microscopy, fibrillar or membranous structures were seen along with synaptic vesicles and dense-core granules. Moreover, around the cells containing PGs, a few synaptic junctions with neighboring cells were observed, indicating that the cells contributing to formation of PGs were neuronal cells. The positive immunoreactivity of AKR mouse PGs for the antibody KM279 suggests that the PGs and similar structures in other species may share a common antigenicity. Thus, it is assumed that PGs in AKR mice might result from some abnormalities in glucose metabolism.
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  • 63
    ISSN: 1432-0533
    Keywords: Key words Presenilin ; Cerebral infarction ; Astrocytoma ; Glial cells ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Presenilins, some gene mutations of which are associated with familial Alzheimer’s disease (AD), are expressed mainly in neurons in normal brains and brains from patients clinicopathologically diagnosed as AD. They are thought to be related to cell death and survival. We studied the immunolocalization of presenilin to investigate its possible relation to cell death and glial proliferation, using two antibodies against different portions of the presenilin 1 protein, in human brains with cerebral infarction and in astrocytoma, where abundant cell death and glial proliferation are present. Expression of presenilin epitopes was more marked in glial cells than in neurons in and around the ischemic focus, and it was also robust in astrocytoma cells. These findings suggest that presenilins are functioning not only in neurons but also in glial cells in reactive and neoplastic proliferation.
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  • 64
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    Anatomy and embryology 199 (1999), S. 291-299 
    ISSN: 1432-0568
    Keywords: Key words Gustatory papillae ; Embryonic development ; Fetal development ; Immunohistochemistry ; Innervation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  Taste buds in humans originate from approximately the 8th postovulatory week under the influence of ingrowing nerve fibers. Since they develop from local epithelium, it is of interest whether or not prospective taste cells maintain or develop characteristics of epithelial cells that are different from those of the adjacent epithelium during differentiation. The aim of this study was to monitor changes of the distribution of the cytokeratin filaments (CKs) 8, 18, 19 and 20 (”gastrointestinal” type), CK 7 (”ductal” type), and CK 13 (maturation ”mucosa type”), as well as vimentin in developing human taste buds and adjacent squamous epithelium. With the exception of CK13, which remains negative in taste bud anlagen and adult taste buds, all cytokeratins tested were present in taste cells. With the progress of development, the distribution of CKs becomes more and more restricted to taste cells and salivatory ducts as well as Ebner gland cells. Only CK20 is exclusively specific to taste bud anlagen and sometimes to individual bipolar cells occurring in early stages (week 8–9). Vimentin was located mainly in mesodermal derivatives but also in perigemmal epithelial cells during all stages of development. The occurrence of vimentin in ”borderline” epithelia that interface with underlying connective tissue, i.e., in a region of discontinuity, may be associated with particular events in development, cell migration or even dedifferentiation.
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  • 65
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    Archives of dermatological research 291 (1999), S. 511-516 
    ISSN: 1432-069X
    Keywords: Key words Melanocyte ; Naevus ; Melanoma ; Immunohistochemistry ; Monoclonal antibody
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The distribution of melanocytes in human skin has been observed to vary within and among individuals, yet little is known of the factors that determine the density of these pigment cells. These factors were explored in a molecular epidemiological study conducted among a population-based sample of 97 male subjects aged over 50 years in Queensland, Australia. Information relating to environmental and phenotypic factors was collected through face-to-face interviews and physical examination of all participants. In addition, 2-mm biopsies of representative skin were taken from the dorsum of the hand and another anatomical site. Melanocytes were identified by cytoplasmic staining with the B8G3 (anti-TRP1) monoclonal antibody using standard immunohistochemical techniques. Melanocyte counts were performed blind by two observers. On crude analysis, melanocyte density decreased with advancing age (P = 0.0002), and increased with increasing number of naevi (P = 0.01). Other pigmentary characteristics (such as hair and eye colour and depth of tan) were not associated with epidermal melanocyte density. Melanocyte density varied significantly by anatomical site (P = 0.02), with highest densities observed on the back/shoulders (n = 50, 17.1 ± 8.8 cells/mm, mean ± SD) followed by the upper limbs (n = 11, 12.6 ± 8.8 cells/mm) and lower limbs (n = 14, 14.4 ± 5.9 cells/mm). Lowest melanocyte densities were recorded on the anterior trunk (n = 3, 3.2 ± 2.4 cells/mm). These findings confirm the results of earlier studies in which site-specific differences in melanocyte density have been found. We speculate that the unequal distribution of melanocytes may partially explain the site-specific incidence of melanoma, offering fresh perspectives on the aetiology of this cancer.
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  • 66
    ISSN: 1432-069X
    Keywords: Key words Chronic diabetic wounds ; Human ; fibroblasts ; Wound healing ; Cell culture ; Proliferation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Patients with diabetes mellitus experience impaired wound healing often resulting in chronic foot ulcers. Hospital discharge data indicate that 6–20% of all diabetic individuals hospitalized (mostly with type 2 diabetes) have a lower extremity ulcer. Maintaining glucose levels at acceptable levels (below 10 mmol/l) is considered to be an important part of the clinical treatment, but the exact mechanism by which diabetes delays wound repair is not yet known. We studied this phenomenon by determining the potential of fibroblasts isolated from the ulcer sites of four patients with non-insulin-dependent diabetes mellitus to proliferate in vitro. Controls were fibroblasts isolated from normal skin of the upper leg of five healthy age-matched volunteers and of six non-insulin-dependent diabetes patients. Proliferative capacity was analysed by evaluation of plates after trypsinization and [3H]thymidine incorporation. Fibroblast morphology was studied by light and transmission electron microscopy. Diabetic ulcer fibroblasts, measured by [3H]thymidine incorporation, proliferated significantly more slowly than the nonlesional control fibroblasts (P 〈 0.00047) and age-matched control fibroblasts (P 〈 0.00003). After culturing the fibroblasts for a prolonged period in high-glucose (27.5 mM) and low-glucose (5.5 mM, i.e. physiological) medium, this difference in proliferation rate between diabetic ulcer fibroblasts and nonlesional diabetic fibroblasts remained (P 〈 0.0001 for high-glucose and P 〈 0.0009 for low-glucose on day 7). Fibroblast proliferation in all three groups was slightly lower in high-glucose than in low-glucose medium, although not significantly at any time-point. Light microscopy showed diabetic ulcer fibroblasts to be large and widely spread. Transmission electron microscopy of cultured diabetic ulcer fibroblasts and nonlesional diabetic skin fibroblasts revealed a large dilated endoplasmic reticulum, a lack of microtubular structures and multiple lamellar and vesicular bodies. These results show a diminished proliferative capacity and abnormal morphology of fibroblasts derived from diabetic ulcers of non-insulin-dependent diabetes patients.
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  • 67
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    Archives of dermatological research 291 (1999), S. 195-200 
    ISSN: 1432-069X
    Keywords: Key words Epidermis ; Immunohistochemistry ; Protease ; Psoriasis ; Stratum corneum chymotryptic ; enzyme
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Stratum corneum chymotryptic enzyme (SCCE) is a serine protease which may function in the turnover of the stratum corneum by means of degradation of intercellular adhesive structures between corneocytes. It is also potentially an epidermal activating enzyme for cytokines such as interleukin-1β. The aim of this work was to study the expression of SCCE in psoriatic epidermis by means of immunohistochemistry, and to elucidate the nature of the SCCE present in psoriatic scales by means of biochemical analyses. In comparison to normal skin the number of cell layers expressing SCCE in psoriatic lesions was consistently increased. In nonlesional psoriatic skin the pattern of SCCE expression varied. It was similar to the pattern in normal skin in some biopsies, whereas in other biopsies evidence of an increased expression of SCCE was found. By means of zymography and immunoblotting, extracts of psoriatic scales were found to contain active SCCE as well as enzymatically inactive SCCE precursor. Also the effects of inhibitors on the activity towards a chromogenic protease substrate in the extracts after partial purification by gel exclusion chromatography were compatible with the presence of enzymatically active SCCE. We conclude that the expression of SCCE in psoriasis may be upregulated, and that the conversion of inactive SCCE-precursor to active SCCE occurs in the psoriatic lesion. The possible role of SCCE in the pathophysiology of psoriasis remains to be elucidated, but should be considered in future studies.
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  • 68
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    Archives of dermatological research 291 (1999), S. 238-240 
    ISSN: 1432-069X
    Keywords: Key words Cysteine protease ; Bleomycin hydrolase ; Keratinocyte ; Skin cancers ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 69
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    Archives of dermatological research 291 (1999), S. 247-252 
    ISSN: 1432-069X
    Keywords: Key words T cell activation ; Nickel ; Human ; Interferon-gamma
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Contact hypersensitivity to nickel is the most common form of allergic contact dermatitis. To gain insight into the induction of this frequent disease, T cell reactivity towards nickel was investigated in “nonallergic” individuals defined as those with no skin manifestations and a negative patch test towards NiSO4. Surprisingly, we found that nickel induced proliferation of peripheral blood mononuclear cells (PBMC) from 16 of 18 adult individuals tested. This activation was specific, and no stimulation of PBMC was observed using control stimulants at equimolar concentrations. Furthermore, the NiSO4-induced activation required the presence of professional antigen-presenting cells. To describe the functional capacity of the nickel-inducible T cells, cytokine release was investigated in both nickel-allergic and nonallergic individuals. The T cells from both groups released interferon-γ but no interleukin-4 upon stimulation with nickel, suggesting that the functional capacities of these cell populations were similar in nickel-allergic and nonallergic individuals. Thus, at this level, no qualitative differences could be demonstrated between T cells obtained from nickel-allergic and nonallergic individuals.
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  • 70
    ISSN: 1432-069X
    Keywords: Key words Serotonin ; Allergic contact dermatitis ; Immunohistochemistry ; High-performance liquid ; chromatography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Allergic contact dermatitis (ACD) is a common clinical condition leading to considerable morbidity. We have recently demonstrated that ketanserin, a serotonin antagonist, significantly inhibits nickel sulphate-induced ACD. Furthermore, serotonin-immunoreactive (IR) cells have previously been demonstrated in normal human cutaneous melanocytes. To further elucidate the role of serotonin in cutaneous contact hypersensitivity, we compared ACD involved skin and uninvolved skin from nickel-allergic patients, and normal skin from healthy volunteers, for the presence of serotonin-like immunoreactive cells using immunohistochemistry. In addition, serotonin concentrations in ACD involved and uninvolved skin were compared by high-performance liquid chromatography (HPLC). In the skin of normal healthy volunteers, the serotonin-IR cells were situated in the basal layer of the epidermis. In uninvolved skin the cells were also situated in the basal layer, but they were more numerous and the immunofluorescence intensity was greater. In involved skin, the IR cells were fewer and they were found higher up in the epidermis. Also, the configuration of these cells was different: they showed enlarged and elongated dendrites as well as dendritic spines. The serotonin antiserum-labelled cells in ACD involved skin were also NKI-beteb positive (the latter is known as a reliable marker of melanocytes). The concentration of serotonin in involved skin was significantly higher than that in uninvolved skin in ACD patients (P 〈 0.05). Taken together, our previous and present results indicate that serotonin plays an important role in ACD. The basal epidermal serotonin-IR cells are more dendritic in ACD, and are found more superficial in the epidermis, where they might release their content of serotonin, thereby influencing the inflammatory process.
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  • 71
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    Archives of dermatological research 291 (1999), S. 303-305 
    ISSN: 1432-069X
    Keywords: Key words Langerhans cells ; Sunburn cells ; UV ; erythema ; Apoptosis ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
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  • 72
    ISSN: 1432-069X
    Keywords: Key words ORS cells ; Melanocytes ; Human ; Organotypic cultures ; Melanosomes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Because outer root sheath (ORS) cells are valuable substitutes for interfollicular epidermal keratinocytes, we wanted to determine whether epidermal equivalents generated from ORS cells and containing cultured melanocytes can serve as an in vitro model for skin pigmentation. In such epidermal equivalents prepared with ORS cells and melanocytes from donors of phototypes II, III and VI, a stratified epithelium resembling normal epidermis developed within 14 days, as documented by histological, ultrastructural (e.g. basement membrane-like structure, keratohyalin granules, keratinosomes) and immunohistochemical (e.g. keratins, integrins, gp80, involucrin, filaggrin) criteria. The melanocytes were localized in the basal layer and accounted for 10% of the total cell number. Heavily pigmented melanocytes from black donors contained regular melanosomes in all stages of maturation, whereas melanocytes derived from white donors contained predominantly melanosomes of stages I and II. Melanosome-laden dendrites were readily detected extending from the heavily pigmented melanocytes, while they were less conspicuous in melanocytes from white donors. The extent of melanosome transfer was independent of the racial origin of the ORS cells. Melanosomes could also be transferred “through racial barriers”. Melanosomes, mainly of stages III and IV, were detected in the ORS cells, being distributed either as single or compound melanosomes, again irrespective of the racial origin of the ORS cells. In conclusion, pigmented epidermal equivalents generated from ORS cells offer practical advantages over other in vitro pigmentation models: (1) the ORS cells are easily and repeatedly available from any donor regardless of age; (2) primary cultures of ORS cells are free of contaminating melanocytes, a bias if using interfollicular epidermal keratinocytes; (3) a high degree of epidermal differentiation is maintained for 3 weeks in fully defined medium, enabling labelling and stimulation experiments to be performed and compounds interfering with melanin pigmentation to be tested.
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  • 73
    ISSN: 1432-069X
    Keywords: Key words Herpes simplex virus ; Cutaneous infection ; Immunohistochemistry ; Polymorphonuclear leukocyte ; Anti-PMN antibody
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We undertook the present study to investigate the role of polymorphonuclear leukocytes (PMN) in defending skin against herpes simplex virus (HSV) infection. For this purpose, we established a mouse model of cutaneous HSV infection. The hind limb footpad skin of 4-week-old ICR mice was abraded linearly once with a feather edge file and infected with various strains of HSV with different virulence. In uninfected control mice, PMN appeared at the abraded skin lesion within 24 h, and were eliminated from the epidermis after 3 days. Mice inducted with a highly virulent strain of HSV demonstrated wide and severe erythematous lesions of the footpad skin and histologically, virus antigen-positive ballooning degenerated keratinocytes were observed. However, in infections with attenuated strains of HSV, the epidermis was regenerated and a viral antigen was discharged within 5 days, together with any infiltrated PMN. Macrophages and NK cells numbered less than PMN. In mice treated with anti-PMN antiserum before HSV infection, PMN infiltration was significantly suppressed 1 day after infection, and these animals developed a severe cutaneous disease even if infected with an attenuated virus. These results indicate the importance of PMN in the control of HSV cutaneous infections, especially in the primary infectious phase.
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  • 74
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    Immunogenetics 49 (1999), S. 438-445 
    ISSN: 1432-1211
    Keywords: Key words PA28 ; Proteasome ; Gene structure ; Evolution ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  Two proteasome activators PA28α and β, which have been implicated in antigen processing for loading class I MHC molecules, are synthesized in response to Ifn-γ. The human genes encoding these activators (PSME1 and PSME2, respectively) were analyzed by sequencing. Each gene comprised 11 exons, consistent with gene duplication during vertebrate evolution. The intron/exon organization of both genes was highly conserved, the major difference being the absence of the exon encoding the lysine and glutamic acid-rich 'KEKE' motif in PA28β. Two other genes of relevance to the immune system were located close to those for PA28 at 14q11.2 including ISGF3G, a protein involved in transcription after IFNα signalling. These sequences were also characterized.
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  • 75
    ISSN: 1432-1211
    Keywords: Key words NK cells ; Human ; Surface molecule ; Lectin superfamily ; NK gene complex
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract  Natural killer (NK) cells constitute the third major population of lymphocytes. They possess the inherent capacity to kill various tumor and virally infected cells and mediate the rejection of bone-marrow grafts in lethally irradiated animals. A large family of NK cell receptors belong to the C-type lectin superfamily and are localized to the NK gene complex on Chromosome (Chr) 6 in the mouse and Chr 12 in the human. Genes in the NK gene complex encode type II receptors and examples include the families of NKR-P1, Ly-49, and NKG2 receptors. Examples of other C-type lectin-like NK cell receptors that occur as individual genes are CD94, CD69, and AICL. Here we report the molecular characterization and chromosomal mapping of a human lectin-like transcript (LLT1) expressed on NK, T, and B cells and localized to the NK gene complex within 100 kilobases of CD69. The cDNA encodes a predicted protein of 191 amino acid residues with a transmembrane domain near the N-terminus and an extracellular domain of 132 amino acid residues with similarity to the carbohydrate recognition domain of C-type lectins. The predicted protein of LLT1 shows 59 and 56% similarity to AICL and CD69, respectively. The predicted protein does not contain any intracellular ITIM motifs, suggesting that LLT1 may be involved in mediating activation signals.
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  • 76
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    International journal of colorectal disease 14 (1999), S. 212-218 
    ISSN: 1432-1262
    Keywords: Key words Cyclo-oxygenase ; Colon carcinogenesis ; Crohn’s disease ; Familiar adenomatous polyposis coli ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  Deregulation of cyclo-oxygenase isozyme expression has been shown to be a consistent feature of inflammatory bowel diseases and colorectal cancer in humans. This study investigated the cellular localization of aberrant cyclo-oxygenase expression in normal and diseased colon. Biopsies of seven normal colonic tissues, eight tissue samples from patients suffering from Crohn’s disease, five polyps from patients with familiar adenomatous polyposis coli, and ten sporadic adenocarcinomas were analyzed using isozyme-selective immunoprecipitation, western blotting, and immunohistochemistry. Cyclo-oxygenase-1 expression was demonstrated in normal human colon, Crohn’s disease, and colorectal tumors. In normal colon and also in adenomatous polyps, cyclo-oxygenase-1 specific immunosignals were localized to epithelial cells of the upper part of the crypts and endocrine cells of the lower part. In Crohn’s disease cyclo-oxygenase-1 expression was restricted to cells of the inflammatory infiltrate. While barely detectable in normal colon, cyclo-oxygenase-2 protein was strongly increased in epithelial cells located in the uppermost part of the crypts, in surface epithelial cells, and in mononuclear cells of the lamina propria of Crohn’s disease. The constitutive overexpression of cyclo-oxygenase-2 protein observed in the majority of the adenomatous polyps and all adenocarcinomas was attributed to both epithelial and interstitial cells in that the latter predominated in adenomas, and epithelial cells were the prevailing cyclo-oxygenase-2 expressing cell type in adenocarcinomas. In conclusion, both autocrine and paracrine effects of aberrant cyclo-oxygenase-2 expression may contribute to the development of Crohn’s disease and colonic tumor development.
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  • 77
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    Experimental brain research 128 (1999), S. 539-542 
    ISSN: 1432-1106
    Keywords: Key words Silent period ; Transcranial magnetic stimulation ; Motor cortex ; Epidural recordings ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  We investigated the nature of the silent period (SP) following transcranial magnetic stimulation by recording corticospinal volleys in a patient with implanted cervical epidural electrodes. Single suprathreshold test stimuli and paired stimuli at interstimulus intervals (ISIs) of 50–200 ms were delivered while the subject maintained a constant background contraction. The silent period duration from a single test stimulus was 357±62 ms. The test motor-evoked potentials were markedly reduced at all the ISIs tested. The I (indirect) waves induced by the test stimulus were largely unchanged at an ISI of 50 ms, suggesting that there was little change in motor cortex excitability. However, the corticospinal volleys, especially the late I waves, were substantially reduced at ISIs of 100 ms, 150 ms, and 200 ms. Our findings suggest that the early part of the SP is mainly due to spinal mechanisms, while the late part of the SP is related to reduced motor cortex excitability.
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  • 78
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    Experimental brain research 128 (1999), S. 550-556 
    ISSN: 1432-1106
    Keywords: Key words Selective attention ; Kinematics ; Human ; Visual pathways
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  In solving the selection-for-action problem, it is believed that attentional mechanisms enable dominance of target over non-target objects. However, under some conditions, information from non-target objects ”interferes” with the action to a relevant target. We investigated the possibility that this interference may result when the irrelevant object activates a specific subset of visuomotor pathways. Participants reached to grasp three-dimensional stimuli while actively attending to a nearby flanker object. The means by which the flanker was presented was manipulated. This relevant object was illuminated either abruptly or gradually. The parvocellular pathway in early visual processing is equally activated in both conditions. The magnocellular pathway is strongly activated by abrupt presentation and weakly activated with gradual presentation of the flanker object. Kinematics of the reach-to-grasp action to the target showed signs of interference only in the sudden illumination condition. This suggests a dissociation between dorsal and ventral cortical streams in terms of relevance for action. Our data suggests that this effect is not due to early visual-pathway differences, but instead reveals a property of a transient object-based visual attention mechanism.
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  • 79
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    Experimental brain research 124 (1999), S. 1-7 
    ISSN: 1432-1106
    Keywords: Key words Temporal cortex ; Connectivity ; Human ; Interhemispheric transfer ; Talairach coordinates
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  The human anterior commissure is believed, by extrapolation from data obtained in macaque monkeys, to convey axons from the temporal and orbitofrontal cortex. Reports of interhemispheric transfer and sexual dimorphism related to the anterior commissure, however, make more precise data on the human anterior commissure desirable. We investigated the connectivity of the human anterior commissure in six adults (male and female) that had circumscribed hemispheric lesions in temporal, frontal, parietal or occipital cortices or in infrapallidal white matter using the Nauta for anterogradely degenerating axons. Axons originating in the inferior part of temporal or occipital lobes, occipital convexity and possibly central fissure and prefrontal convexity were found to cross the midsagittal plane in the anterior commissure. The largest contigent of commissural axons originated in the inferior part of the temporal lobe; it displayed a roughly topographic organization, preferentially running through the inferior part of the commissure. The inferior temporal contigent seemed to reach homotopic and heterotopic targets in the opposite hemisphere. Among the latter were the amygdala and possibly the orbitofrontal cortex. The present data suggest that the human anterior commissure conveys axons from much larger territories than expected from work on non-human primates. Similarly to the human and non-human primate corpus callosum, the anterior commissure is roughly topographically organized and participates in heterotopic connectivity.
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  • 80
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    Experimental brain research 126 (1999), S. 200-204 
    ISSN: 1432-1106
    Keywords: Key words Motor development ; Anticipatory postural adjustments ; Bimanual coordination ; Children ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  Anticipatory postural adjustments (APA) are needed to perform a movement without perturbing posture. We investigated the development of APA in 3- to 4-year-old children during a bimanual load-lifting task. The task required maintaining a stable elbow position despite imposed or voluntary unloading of the forearm. Although children can compensate the consequences of unloading by using APA, their performance did not reach an adults’ level. In addition, children showed high intra-individual variability in the voluntary situation, revealed by the coexistence of both adult-like and immature patterns in kinematic and electromyographic data. In conclusion, the present study reports that APA, associated with a bimanual load-lifting task, are still being set up in 3- to 4-year-old-children. The intra-individual variability should decrease with age and be associated with a progressive mastering of the timing parameters characterizing APA.
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  • 81
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    Experimental brain research 124 (1999), S. 273-280 
    ISSN: 1432-1106
    Keywords: Key words Vestibular system ; Posture control ; Balance ; Cross-spectral analysis ; Coherency ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  Galvanic vestibular stimulation serves to modulate the continuous firing level of the peripheral vestibular afferents. It has been shown that the application of sinusoidally varying, bipolar galvanic currents to the vestibular system can lead to sinusoidally varying postural sway. Our objective was to test the hypothesis that stochastic galvanic vestibular stimulation can lead to coherent stochastic postural sway. Bipolar binaural stochastic galvanic vestibular stimulation was applied to nine healthy young subjects. Three different stochastic vestibular stimulation signals, each with a different frequency content (0–1 Hz, 1–2 Hz, and 0–2 Hz), were used. The stimulation level (range 0.4–1.5 mA, peak to peak) was determined on an individual basis. Twenty 60-s trials were conducted on each subject – 15 stimulation trials (5 trials with each stimulation signal) and 5 control (no stimulation) trials. During the trials, subjects stood in a relaxed, upright position with their head facing forward. Postural sway was evaluated by using a force platform to measure the displacements of the center of pressure (COP) under each subject’s feet. Cross-spectral measures were used to quantify the relationship between the applied stimulus and the resulting COP time series. We found significant coherency between the stochastic vestibular stimulation signal and the resulting mediolateral COP time series in the majority of trials in 8 of the 9 subjects tested. The coherency results for each stimulation signal were reproducible from trial to trial, and the highest degree of coherency was found for the 1- to 2-Hz stochastic vestibular stimulation signal. In general, for the nine subjects tested, we did not find consistent significant coherency between the stochastic vestibular stimulation signals and the anteroposterior COP time series. This work demonstrates that, in subjects who are facing forward, bipolar binaural stochastic galvanic stimulation of the vestibular system leads to coherent stochastic mediolateral postural sway, but it does not lead to coherent stochastic anteroposterior postural sway. Our finding that the coherency was highest for the 1- to 2-Hz stochastic vestibular stimulation signal may be due to the intrinsic dynamics of the quasi-static postural control system. In particular, it may result from the effects of the vestibular stimulus simply being superimposed upon the quiet-standing COP displacements. By utilizing stochastic stimulation signals, we ensured that the subjects could not predict a change in the vestibular stimulus. Thus, our findings indicate that subjects can act as ”responders” to galvanic vestibular stimulation.
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  • 82
    ISSN: 1432-1106
    Keywords: Key words Locomotion ; Load ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  Prior work from mammals suggests that load experienced by extensor muscles of the hindlimbs (i.e. Duysens and Pearson 1980; Pearson and Collins 1993; Fouad and Pearson 1997) or cutaneous afferents from the plantar surface of the foot (Duysens and Pearson 1976; Guertin et al. 1995) enhances activity in extensor muscles during the stance phase, and delays the onset of flexor activity associated with the swing phase. The presumed functional significance of this phenomenon is that extensor activity of the supporting limb during walking can: (a) reinforce the supporting function in proportion to the load experienced, and (b) prolong the stance phase until unloading of the limb has occurred. Whether a similar functional role exists for load-sensitive afferents during walking in the human is unknown. In this study, the effect of adding or removing a substantial load (30% of body weight) at the centre of mass was studied in healthy adult human subjects. Loads were applied near the centre of mass to avoid the need for postural adjustments which might confound the interpretation of the results. Subjects walked on a treadmill with either: (a) a sustained increase or decrease in load, or (b) a sudden unexpected increase or decrease in load. In general, subjects responded to the changes in load by changing the amplitude of the extensor electromyographic (EMG) bursts. For example, with sudden unexpected additions in load, the average increase in amplitude was 40% for the soleus across the stance phase, and 134% for the quadriceps during the early part of the stance phase. Extensor EMGs increased with both sustained and sudden increases in load. Extensor EMG durations also increased (average increase in duration of 4% for soleus with sudden loading, and 7% for sustained loading). Cycle duration hardly changed (average increase of 0.5% with both sudden and sustained loading). These results differ from those of infants subjected to a similar perturbation during supported walking. A large change in timing (i.e. an increase in the duration of the stance phase by 30% and the step cycle by 28%) was seen in the infants, with no change in the amplitude of the EMG burst (Yang et al. 1998). These results suggest that the central nervous system can control the timing and amplitude of extensor EMG activity in response to loading independently. Maturation of the two components most likely occurs independently. In the adult, independent control of the two components may provide greater flexibility of the response.
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  • 83
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    Experimental brain research 126 (1999), S. 235-251 
    ISSN: 1432-1106
    Keywords: Key words Motor learning and memory ; Perseveration ; Prefrontal cortex ; Reversal learning ; Basal ganglia ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  The ability to inhibit previously learned visuomotor associations is essential for efficient learning of novel behaviors. While the neural basis of the system that might control interactions between competing motor memories is not known, it has been demonstrated that animals with ventral and orbital prefrontal cortex (PFC) deficits have particular difficulties in learning to withhold responses to previously conditioned sensory stimuli. Here we measured regional cerebral blood flow (rCBF), using positron emission tomography, during learning of a novel motor task that required inhibition of a previously learned motor memory. Subjects (n=24) learned reaching movements in a force field (field A). After a variable time interval, some subjects (n=15) learned to reach in a field with a reversed pattern of forces (field B). When the time interval was short (10 min), learning in field B was coincident with a reactivation of regions that had become initially activated during learning in field A: the left putamen and bilaterally in the dorsolateral PFC. Behaviorally, this was accompanied with perseveration that lasted for hundreds of movements, suggesting an instantiation of the internal model for field A during learning in field B. Neither the reactivation nor the perseveration were observed in a different group of subjects that learned field B at 5.5 h. We found that the regions which significantly differentiated the two groups during learning of B were in the ventrolateral PFC (bilaterally): there were sharp decreases in rCBF here in the 5.5 group but not in the 10-min group. At 5.5 h motor learning again involved the striatum, but this time in the left caudate. Neither the caudate nor the ventral PFC had exhibited learning-related activity in field A. Instead, they showed changes in rCBF during the reversal of the learning problem when the previously acquired motor memory was successfully gated. The results demonstrate that: (1) perseveration of a competing motor memory may be linked to reactivation of the neural circuit that participated in acquiring that memory, and (2) the ventral PFC may play an important role in the inhibitory control of the competing motor memory.
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  • 84
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    Keywords: Key words Corpus callosum ; Interhemispheric transfer ; Positron emission tomography ; Split brain ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  We studied with PET the intra- and interhemispheric pathways subserving a simple, speeded-up visuomotor task. Six normal subjects and one patient with a complete section of the corpus callosum (M.E.) underwent regional cerebral blood flow (rCBF) measurements under conditions of lateralized tachistoscopic visual presentations in a simple manual reaction time paradigm. Confirming previous behavioural findings, we found that on average crossed hand and/or hemifield conditions, i.e. those requiring an interhemispheric transfer of information, yielded a longer RT than uncrossed conditions. This difference (0.7 ms) was dramatically larger (45.6 ms) in the callosum-sectioned patient M.E. In normal subjects the cortical areas selectively activated in uncrossed and crossed conditions were different. In the former condition, most activation foci were anterior to the ventral anterior commissure (VAC) plane, whereas in the latter there was a prevalent parietal and occipital activation. This shows that a simple model in which the cortical visuo-motor pathways are similar in the intra- and the interhemispheric condition, with an extra callosal route for the latter, is too simplistic. Furthermore, these results suggest that the bulk of visuomotor interhemispheric transfer takes place through the widespread callosal fibres interconnecting the parietal cortices of the two hemispheres. The pattern of activation in the two crossing conditions was markedly different in M.E., in whom interhemispheric transfer might take place via his intact anterior commissure or subcortical commissures.
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  • 85
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    Experimental brain research 125 (1999), S. 43-49 
    ISSN: 1432-1106
    Keywords: Key words Proprioception ; Visual localization ; Visual context ; Multisensory integration ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  In a previous study we investigated how the CNS combines simultaneous visual and proprioceptive information about the position of the finger. We found that localization of the index finger of a seen hand was more precise (a smaller variance) than could reasonably be expected from the precision of localization on the basis of vision only and proprioception only. This suggests that, in localizing the tip of the index finger of a seen hand, the CNS may make use of more information than proprioceptive information and visual information about the fingertip. In the present study we investigate whether this additional information stems from additional sources of sensory information. In experiment 1 we tested whether seeing an entire arm instead of only the fingertip gives rise to a more precise proprioceptive and/or visual localization of that fingertip. In experiment 2 we checked whether the presence of a structured visual environment leads to a more precise proprioceptive localization of the index finger of an unseen hand. In experiment 3 we investigated whether looking in the direction of the index finger of an unseen hand improves proprioceptive localization of that finger. We found no significant effect in any of the experiments. The results refute the hypothesis that the investigated effects can explain the previously reported very precise localization of a seen hand. This suggests that localization of a seen finger is based exclusively on proprioception and on vision of the finger. The results suggest that these sensory signals may contain more information than is described by the magnitude of their variances.
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  • 86
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    Experimental brain research 125 (1999), S. 139-152 
    ISSN: 1432-1106
    Keywords: Key words Reaching movements ; Direction ; Amplitude ; Initial kinematics ; Spatial variability ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  The accuracy of reaching movements to memorized visual target locations is presumed to be determined largely by central planning processes before movement onset. If so, then the initial kinematics of a pointing movement should predict its endpoint. Our study examined this hypothesis by testing the correlation between peak acceleration, peak velocity, and movement amplitude and the correspondence between the respective spatial positions of these kinematic landmarks. Subjects made planar horizontal reaching movements to targets located at five different distances and along five radially arrayed directions without visual feedback during the movements.The spatial dispersion of the positions of peak acceleration, peak velocity, and endpoint all tended to form ellipses oriented along the movement trajectory. However, whereas the peaks of acceleration and velocity scaled strongly with movement amplitude for all of the movements made at the five target distances in any one direction, the correlations with movement amplitude were more modest for trajectories aimed at each target separately. Furthermore, the spatial variability in direction and extent of the distribution of positions of peak acceleration and peak velocity did not scale differently with target distance, whereas they did for endpoint distributions. Therefore, certain features of the final kinematics are evident in the early kinematics of the movements as predicted by the hypothesis that they reflect planning processes. However, endpoint distributions were not completely predetermined by the Initial kinematics. In contrast, multivariate analysis suggests that adjustments to movement duration help compensate for the variability of the initial kinematics to achieve desired movement amplitude. These compensatory adjustments do not contradict the general conclusion that the systematic patterns in the spatial variability observed in this study reflect planning processes. On the contrary, and consistent with that conclusion, our results provide further evidence that direction and extent of reaching movements are planned and determined in parallel over time.
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  • 87
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    Keywords: Key words Three-dimensional pointing ; Human ; Remembered targets
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  The accuracy of visually guided pointing movements decreases with speed. We have shown that for movements to a visually defined remembered target, the variability of the final arm endpoint position does not depend on movement speed. We put forward a hypothesis that this observation can be explained by suggesting that movements directed at remembered targets are produced without ongoing corrections. In the present study, this hypothesis was tested for pointing movements in 3D space to kinesthetically defined remembered targets. Passive versus active acquisition of kinesthetic information was contrasted. Pointing errors, movement kinematics, and joint-angle coordination were analyzed. The movements were performed at a slow speed (average peak tangential velocity of about 1.2 m/s) and at a fast speed (2.7 m/s). No visual feedback was allowed during the target presentation or the movement. Variability in the final position of the arm endpoint did not increase with speed in either the active or the passive condition. Variability in the final values of the arm-orientation angles determining the position of the forearm and of the upper arm in space was also speed invariant. This invariance occurred despite the fact that angular velocities increased by a factor of two for all the angles involved. The speed-invariant variability supports the hypothesis that there is an absence of ongoing corrections for movements to remembered targets: in the case of a slower movement, where there is more time for movement correction, the final arm endpoint variability did not decrease. In contrast to variability in the final endpoint position, the variability in the peak tangential acceleration increased significantly with movement speed. This may imply that the nervous system adopts one of two strategies: either the final endpoint position is not encoded in terms of muscle torques or there is a special on-line mechanism that adjusts movement deceleration according to the muscle-torque variability at the initial stage of the movement. The final endpoint position was on average farther from the shoulder than the target. Constant radial-distance errors were speed dependent in both the active and the passive conditions. In the fast speed conditions, the radial distance overshoots of the targets increased. This increase in radial-distance overshoot with movement speed can be explained by the hypothesis that the final arm position is not predetermined in these experimental conditions, but is defined during the movement by a feedforward or feedback mechanism with an internal delay.
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  • 88
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    Experimental brain research 125 (1999), S. 265-270 
    ISSN: 1432-1106
    Keywords: Key words Tendon reflexes ; Biceps femoris ; Gait ; Ia afferents ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  During gait it is generally accepted that there is a reduction in amplitude of H-reflexes as compared to standing. For short-latency stretch reflexes, however, it is less clear whether a similar reduction in reflex gain is present during locomotion. Stretches of constant amplitude are hard to produce under these circumstances and for this reason some previous studies on the biceps femoris (BF) have used ”reduced gait” in which the stimulated leg is stepping on the spot while the contralateral leg is walking on a treadmill. With this method it was possible to show that BF tendon jerk reflexes are larger at end swing and therefore are likely to contribute to the EMG burst normally occurring in that part of the step cycle when the BF is rapidly stretched. In the present study two questions were addressed: first, whether the reflex is different in size during gait compared to standing and, second, whether it is modulated in size during the gait cycle not only during reduced but also during normal gait. It was found that during both types of gait there was a general reflex depression with regard to the respective control values obtained during standing at similar EMG activity levels. In previous studies on soleus and quadriceps, discrepancies between EMG activity and reflex amplitude have been ascribed to changes in presynaptic inhibition of Ia terminals mediating the afferent volley of the reflex. Based on the data presented, this may also be true for the BF. In both normal and reduced gait the reflex was similarly modulated in size, showing a maximum at the end of swing. This similarity implies that reduced gait may be useful as an acceptable alternative for normal gait in studies on phase-dependent reflex modulation during locomotion.
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  • 89
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    Keywords: Key words Hyperventilation ; Magnetoencephalography ; Somatosensory cortex ; Auditory cortex ; Somatosensory evoked response ; Auditory evoked response ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  It is well established that voluntary hyperventilation (HV) slows down electroencephalographic (EEG) rhythms. Little information is available, however, on the effects of HV on cortical responses elicited by sensory stimulation. In the present study, we recorded auditory evoked potentials (AEPs) and magnetic fields (AEFs), and somatosensory evoked magnetic fields (SEFs) from healthy subjects before, during, and after a 3- to 5-min period of voluntary HV. The effectiveness of HV was verified by measuring the end-tidal CO2 levels. Long-latency (100–200 ms) AEPs and long-latency AEFs originating at the supratemporal auditory cortex, as well as long-latency SEFs from the primary somatosensory cortex (SI) and from the opercular somatosensory cortex (OC), were all reduced during HV. The short-latency SEFs from SI were clearly less modified, there being, however, a slight reduction of the earliest cortical excitatory response, the N20m deflection. A middle-latency SEF deflection from SI at about 60 ms (P60 m) was slightly increased. For AEFs and SEFs, the center-of-gravity locations of the activated neuronal populations were not changed during HV. All amplitude changes returned to baseline levels within 10 min after the end of HV. The AEPs were not altered when the subjects breathed 5% CO2 in air in a hyperventilation-like manner, which prevented the development of hypocapnia. We conclude that moderate HV suppresses long-latency evoked responses from the primary projection cortices, while the early responses are less reduced. The reduction of long-latency responses is probably mediated by hypocapnia rather than by other nonspecific effects of HV. It is suggested that increased neuronal excitability caused by HV-induced hypocapnia leads to spontaneous and/or asynchronous firing of cortical neurones, which in turn reduces stimulus-locked synaptic events.
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  • 90
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    Experimental brain research 124 (1999), S. 42-52 
    ISSN: 1432-1106
    Keywords: Key words Ocular tracking ; Oculomanual coordination ; Electromyography ; Internal model ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  When the eyes and arm are involved in a tracking task, the characteristics of each system differ from those observed when they act alone: smooth pursuit (SP) latency decreases from 130 ms in external target tracking tasks to 0 ms in self-moved target tracking tasks. Two models have been proposed to explain this coordination. The common command model suggests that the same command be addressed to the two sensorimotor systems, which are otherwise organized in parallel, while the coordination control model proposes that coordination is due to a mutual exchange of information between the motor systems. In both cases, the interaction should take into account the dynamic differences between the two systems. However, the nature of the adaptation depends on the model. During self-moved target tracking a perturbation was applied to the arm through the use of an electromagnetic brake. A randomized perturbation of the arm increased the arm motor reaction time without affecting SP. In contrast, a constant perturbation produced an adaptation of the coordination control characterized by a decrease in arm latency and an increase in SP latency relative to motor command. This brought the arm-to-SP latency back to 0 ms. These results support the coordination control model.
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  • 91
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    Experimental brain research 124 (1999), S. 287-294 
    ISSN: 1432-1106
    Keywords: Key words Magnetoencephalography ; V1 cortex ; V2 cortex ; V6 complex ; Horizontal meridian ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  We recorded whole-scalp magnetoencephalographic (MEG) responses to black-and-white checkerboards to study whether the human cortical responses are quantitatively similar to stimulation of the lower and upper visual field at small, 0–6°, eccentricities. All stimuli evoked strongoccipital responses peaking at 50–100 ms (mean 75 ms). The activation was modeled with a single equivalent current dipole in the contralateral occipital cortex, close to the calcarine fissure, agreeing with an activation of the V1/V2 cortex. The dipole was, on average, twice as strong to lower than to upper field stimuli. Responses to hemifield stimuli that extended to both lower and upper fields resembled the responses to lower field stimuli in source current direction and strength. These results agree with psychophysical data, which indicate lower visual field advantage in complex visual processing. Parieto-occipital responses in the putative V6 complex were similar to lower and upper field stimuli.
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  • 92
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    Experimental brain research 126 (1999), S. 289-306 
    ISSN: 1432-1106
    Keywords: Key words Motor control ; Trajectory formation ; Coordination ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  The degrees of freedom problem is often posed by asking which of the many possible degrees of freedom does the nervous system control? By implication, other degrees of freedom are not controlled. We give an operational meaning to ”controlled” and ”uncontrolled” and describe a method of analysis through which hypotheses about controlled and uncontrolled degrees of freedom can be tested. In this conception, control refers to stabilization, so that lack of control implies reduced stability. The method was used to analyze an experiment on the sit-to-stand transition. By testing different hypotheses about the controlled variables, we systematically approximated the structure of control in joint space. We found that, for the task of sit-to-stand, the position of the center of mass in the sagittal plane was controlled. The horizontal head position and the position of the hand were controlled less stably, while vertical head position appears to be no more controlled than joint motions.
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  • 93
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    Experimental brain research 124 (1999), S. 469-473 
    ISSN: 1432-1106
    Keywords: Key words Form from motion ; Visual development ; Visual acuity ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  The development of dynamic vision was investigated in 400 healthy subjects (200 females and 200 males) aged between 4 and 24 years. The test consisted of a computer-generated random-dot kinematogram in which a Landolt ring was briefly presented as a form-from-motion stimulus. Motion contrast between the ring and background was varied in terms of the percentage of dots moving coherently within the ring in four levels (100%, 50%, 30%, and 20%). The subject’s task was to indicate the position of a gap in the ring (left, right, top, bottom). Results show a clear increase in performance with age for all motion contrast levels, with the greatest changes for the lowest levels. Adult performance was reached at the age of 15 years. Luminance-based static acuity measured with the Landolt test was poorly correlated with acuity for its form-from-motion analogue.
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  • 94
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    Experimental brain research 124 (1999), S. 503-512 
    ISSN: 1432-1106
    Keywords: Key words Reaching movements ; Memory for positions ; Laterality ; Posture copying ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  Many recent studies indicate that memory for final position is superior to memory for movement. There is ambiguity about what is meant by the term final position, however. Is it final spatial location or final posture? According to a recently proposed theory by Rosenbaum et al., which maintains that stored postures form the basis for movement planning, when people try to return to recently reached positions, they should try to adopt the postures they just occupied. An alternative view, which holds that movements are primarily planned with respect to spatial locations, predicts that subjects should tend to return to places in external space. We describe an experiment that tested these opposing predictions. The experiment relied on the notion that if people store and use postures, they should ”copy” the posture adopted with one arm to the other arm when possible. The results support this hypothesis.
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  • 95
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    Keywords: Key words Optokinetic nystagmus ; Positron emission tomography ; Visual motion ; Area V5 ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  Positron emission tomography (PET) was used to address the issue of physiological changes in the cerebral cortex associated to optokinetic nystagmus (OKN) in humans. We studied regional cerebral blood flow in eight volunteers during reflexive induction of OKN by a pattern of dots moving unidirectionally (toward the left side). We used two control conditions, with subjects passively viewing either stationary or incoherently moving dots. This paradigm was designed in order to differentiate the OKN-related activations from blood flow changes related to visual motion. When compared with the stationary condition, OKN activated a set of occipital areas known to be sensitive to visual motion. Bilateral activation was found in the striate cortex (V1) and the parieto-occipital fissure, while area V5, the intraparietal sulcus, and the pulvinar were activated only in the left hemisphere. When compared with incoherent motion, OKN activated the V1 and the parieto-occipital fissure bilaterally and the right lingual gyrus, while a signal decrease was observed in the V5 region in both hemispheres. No significant signal changes were found in areas implicated in saccades or in processing vestibular information. These results indicate that processing of OKN-related information is associated with neural activity in a specific set of visual motion areas and suggest that this network can be asymmetrically activated by a strictly unidirectional stimulation. Results are also discussed in terms of the specific kinds of OKN-related information processing subserved by each area in this network.
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  • 96
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    Experimental brain research 126 (1999), S. 175-186 
    ISSN: 1432-1106
    Keywords: Key words Listing’s plane ; Vergence ; Binocular ; Eye movements ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  Earlier studies have reported temporal rotation of Listing’s plane with convergence of the eyes causing torsion, which is dependent on eye elevation. The amount by which the planes rotate differs from study to study. To gain insight into the functional significance of the temporal tilt of Listing’s plane for vision, we examined whether the rotation of the plane depends on the visual conditions, namely on the stimuli driving vergence. In different conditions, accommodative vergence, disparity-vergence, combinations of disparity with accommodation or depth perception were used and the resulting rotation of Listing’s plane was measured. Our findings show, for the first time, that the relationship between convergence and Listing’s-plane temporal rotation depends on the stimuli driving vergence. When the stimulus contains only disparity cues, vergence and Listing’s plane rotate immediately and consistently among subjects. Accommodative vergence, the mutual couplings between vergence and accommodation, can influence the orientation of Listing’s plane, but they do so in a idiosyncratic way. The largest rotation was elicited by stereograms combining disparity-vergence with depth perception. These findings support the idea of a functional role of Listing’s plane rotation for binocular vision, perhaps for depth perception.
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  • 97
    ISSN: 1432-1106
    Keywords: Key words Grip force ; Force control ; Parabolic flight ; Microgravity ; Hypergravity ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  In the present study, grip forces exerted against a stationary held object were recorded during parabolic flights. Such flight maneuvers induce changes of gravity with two periods of hypergravity, associated with a doubling of normal terrestrial gravity, and a 20 s period of microgravity. Accordingly, the object’s weight changed from being twice as heavy as normally experienced and weightless. Grip-force recordings demonstrated that force control was seriously disturbed only during the first experience of hyper- and microgravity, with the grip forces being exceedingly high and yielding irregular fluctuations. Thereafter, however, grip force traces were smooth, the force level was scaled to the object’s weight under normal and high-G conditions, and the grip force changed in parallel with the weight during the transitions between hyper- and microgravity. In addition, during weightlessness, when virtually no force was necessary to stabilize the object, a low force was established, which obviously represented a reasonable safety margin for preventing possible perturbations. Thus, all relevant aspects of grip-force control observed under normal gravity conditions were preserved during gravity changes induced by parabolic flights. Hence, grip-force control mechanisms were able to cope with hyper- and microgravity, either by incorporating relevant receptor signals, such as those originating from cutaneous mechanoreceptors, or by adequately including perceived gravity signals into control programs. However, the adaptation to the uncommon gravity conditions was not complete following the first experience; finer tuning of the control system to both hyper- and microgravity continued over the measurement interval, presumably with a longer observation period being necessary before a stable performance can be reached.
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    Experimental brain research 129 (1999), S. 156-160 
    ISSN: 1432-1106
    Keywords: Key words Optokinetic nystagmus ; Depth-from-motion ; Transparent motion ; Ambiguous ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  When two visual patterns moving in opposite directions are superimposed, they appear to be at different depths and to slide over each other. Because the stimulus does not specify the depth-order between the surfaces, this transparent motion perception is essentially ambiguous. With prolonged observation, the perceived depth-order of the two moving surfaces reverses spontaneously. In the present study, the correlation between the perceived direction of transparent motion and optokinetic nystagmus (OKN) was examined. While viewing superimposed random-dot patterns moving in opposite horizontal or vertical directions, subjects attempted to fixate the center of the stimulus, while paying attention to either the near or far depth plane, and reported any changes of the direction of surface-motion at the attended depth. Even with attention focused on a particular depth, the spontaneous reversal of transparent motion perception still occurred. This indicates that the perceptual reversal may reflect a preattentive mechanism for depth-from-motion. Furthermore, the OKN slow-phase tended to be in the same direction as the perceived motion of the surface at the attended depth. These results support the idea that the mechanisms for OKN maintenance are sensitive to perception of depth-from-motion and, therefore, cortically mediated.
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  • 99
    ISSN: 1432-1106
    Keywords: Key words Reaching movements ; Grasping movements ; Prehension ; Manual control ; Computational model ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  Reaching and grasping an object can be viewed as the solution of a multiple-constraint satisfaction problem. The constraints include contact with the object with the appropriate effectors in the correct positions as well as generation of a collision-free trajectory. We have developed a computational model that simulates reaching and grasping based on these notions. The model, rendered as an animation program, reproduces many basic features of the kinematics of human reaching and grasping behavior. The core assumptions of the model are: (1) tasks are defined by flexibly organized constraint hierarchies; (2) manual positioning acts, including prehension acts, are first specified with respect to goal postures and then are specified with respect to movements towards those goal postures; (3) goal postures are found by identifying the stored posture that is most promising for the task, as determined by the constraint hierarchy, and then by generating postures that are more and more dissimilar to the most-promising stored posture until a deadline is reached, at which time the best posture that was found during the search is defined as the goal posture; (4) depending on when the best posture was encountered in the search, the deadline for the search in the next trial is either increased or decreased; (5) specification of a movement to the goal posture begins with straight-line interpolation in joint space between the starting posture and goal posture; (6) if an internal simulation of this default movement suggests that it will result in collision with an obstacle, the movement can be reshaped until an acceptable movement is found or until time runs out; (7) movement reshaping occurs by identifying a via posture that serves as a body position to which the actor moves from the starting posture and then back to the starting posture, while simultaneously making the main movement from the starting posture to the goal posture; (8) the via posture is identified using the same posture-generating algorithm as used to identify the goal posture. These processes are used both for arm positioning and, with some elaboration, for prehension. The model solves a number of problems with an earlier model, although it leaves some other problems unresolved.
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  • 100
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    Experimental brain research 128 (1999), S. 309-314 
    ISSN: 1432-1106
    Keywords: Key words GABA ; Bromodeoxyuridine ; Proliferation ; Immunohistochemistry ; Retina ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  The birthdates of GABAergic amacrine cells in the rat retina were investigated by immunocytochemistry using anti-GABA and anti-bromodeoxyuridine (BrdU) antisera. The ratio of co-localization of GABA to BrdU increased gradually from embryonic-day 13 (E13) and showed a peak value on E18 in the central retina and on E20 in the periphery. After birth, until postnatal-day 3 (P3), a few co-localized cells were observed in the inner nuclear layer (INL). However, in the peripheral retina, co-localized cells were observed in the INL and ganglion cell layer until P5. Our results suggest that the birthdates of GABA-immunoreactive cells vary, depending on cell-type and that there is a temporal lag in the GABA-immunoreactive cell production in the peripheral retina relative to the central retina.
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