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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Diseases of the colon & rectum 38 (1995), S. 509-513 
    ISSN: 1530-0358
    Keywords: Colon ; Innervation ; Nerves ; Muscle ; Immunohistochemistry ; Constipation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract PURPOSE: This study was designed to investigate neural and muscular features of the colonic wall in patients with severe idiopathic constipation. METHODS: By using quantitative immunohistochemistry, resected specimens from 14 patients with idiopathic chronic constipation and 17 nonobstructed cancer controls were studied. RESULTS: Routine histology revealed no significant histologic abnormality throughout the colon apart from four cases of melanosis coli. Ratio of the thickness of circular to longitudinal muscle was significantly lower in the left colon in constipated subjects. The myenteric plexus appeared morphologically normal in all subjects. S-100 protein, which stains neuronal supporting tissues, demonstrated an increase in the proportion of neural tissue in the myenteric plexus. There was an increased number of PGP-9.5 immunoreactive nerve fibers in the muscularis propria in constipated patients, and this was significantly higher in the ascending and descending colon. CONCLUSION: Intractably constipated patients have alterations in the neural composition of the colonic myenteric plexus and innervation of the circular muscle.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Diseases of the colon & rectum 38 (1995), S. 983-987 
    ISSN: 1530-0358
    Keywords: Monoclonal antibody ; B72.3 ; Tumor-associated glycoprotein ; Adenocarcinoma ; Colorectal cancer ; Immunohistochemistry ; Radioimmunoscintigraphy ; Radioimmunoguided surgery
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract PURPOSE: Immunolocalization of the tumor-associated glycoprotein 72 antigen with the monoclonal antibody B72.3 has been used as a “cancer marker” in radioimmunoscintigraphy and radioimmunoguided surgery (RIGS). Radioimmunoscintigraphy and RIGS have been used to detect occult metastatic deposits from colorectal adenocarcinoma. It has been suggested that RIGS is superior to histologic examination in detecting lymph node metastases from colorectal cancer. To determine the specificity of immunodetection of the tumor-associated glycoprotein -72 antigen as a marker for metastatic adenocarcinoma, we studied benign intraabdominal lymph nodes with B72.3 and an immunohistochemical technique. METHODS: Formaldehyde-fixed, paraffin-embedded sections of 276 benign abdominal lymph nodes, resected with 35 cases of colonic adenocarcinoma and 33 cases of benign gastrointestinal disorders, were evaluated for B72.3 immunoreactivity using an avidin-biotin complex immunohistochemical technique. Lymph nodes from cases of colonic carcinoma were also studied with cytokeratin immunostaining to help eliminate occult micrometastases. RESULTS: B72.3 immunoreactivity was seen in the germinal centers of benign lymph nodes associated with 49 percent of the cases of colonic adenocarcinoma and 12 percent of the cases of benign gastrointestinal disease. CONCLUSIONS: B72.3 immunoreactivity can be seen in benign abdominal lymph nodes associated with gastrointestinal disease. We advise caution in the use of diagnostic techniques that equate B72.3 immunoreactivity with the presence of adenocarcinoma.
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  • 3
    ISSN: 1530-0358
    Keywords: Colorectal neoplasms ; Immunohistochemistry ; CEA
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract PURPOSE: Submucosa-invasive colorectal carcinoma is a colorectal carcinoma extending only into the submucosal layer. To clarify the metastatic potential of submucosa-invasive colorectal carcinoma, we studied the relationship between the immunohistochemical staining pattern of carcinoembryonic antigen (CEA) and that of lymphatic invasion/ lymph node metastasis. METHODS: We investigated 49 submucosa-invasive colorectal carcinomas resected surgically or endoscopically. CEA distribution patterns of the neoplastic tissues were divided into three patterns: Pattern 1 = luminal type; Pattern 2 = apical cytoplasmic type; and Pattern 3 = diffuse cytoplasmic type. We also observed the submucosal stromal staining of CEA. RESULTS: Lymphatic invasion and lymph node metastasis were found in 48.8 percent (21/43) and 11.6 percent (5/43) of the Pattern 2/Pattern 3 cases, whereas these were seen in none (0/6) of Pattern 1 cases. Lymphatic invasion and lymph node metastasis were found in 63.3 percent (19/30) (chi-squared =21.94;P 〈0.001) and 16.7 percent (5/30) of the positive stromal CEA cases, whereas these were seen in 10.5 percent (2/19) and none (0/14) of the negative stromal CEA cases, respectively. CONCLUSION: Pattern 2/Pattern 3 and stromal CEA can be predictors of the lymph node metastasis with 11.6 percent and 16.7 percent risks.
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  • 4
    ISSN: 1530-0358
    Keywords: Heat shock protein 70 ; HLA-DR ; Colorectal cancer ; Immunohistochemistry ; Prognosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract PURPOSE: The expression of 70,000-Da heat shock protein (HSP 70) and HLA-DR molecules on cancer cells influences immunologic mechanisms that may be of some prognostic significance. The purpose of this study was to examine the relationship among immunohistochemical HSP 70, HLA-DR expression, and clinicopathologic tumor variables, as well as patient survival in a series of 128 colorectal carcinomas. METHOD: A three-step immunoperoxidase staining technique was undertaken for detection of both markers. RESULTS: Of the examined carcinomas 77.3 percent were HSP 70-positive and 74.2 percent were HLA-DR-positive. Increased HSP 70-positive expression correlated significantly with low differentiation (P〈0.05), showed a tendency to characterize advanced stages of disease, and was clearly associated with worse overall survival (P〈0.05). The highest rate of HLA-DR positivity was demonstrated in early stages and was significantly associated with more favorable prognosis (P〈0.001). HSP 70-positive/HLA-DR-negative patients had worse overall survival compared with the rest (P〈0.001). CONCLUSIONS: The resulting opposite effects on prognosis of examined markers seem to be related to different pathophysiologic functional roles on tumor immunology.
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  • 5
    ISSN: 1437-1596
    Keywords: Leukotoxin ; 9,10-epoxy-12-octadecenoic acid ; Immunohistochemistry ; Macrophages ; Leukotoxin ; 9,10-Epoxy-12octadecensdure ; Immunhistochemie ; Makrophagen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Law
    Description / Table of Contents: Zusammenfassung Dieser Artikel untersucht die immunhistochemische Dynamik von Leukotoxin (9,10-Epoxy-12-octadecensäure, LTx) in den Lungen von Ratten, die einer Hyperoxie mit oder ohne Paraquat ausgesetzt waren. Die Ratten wurden behandelt mit 100% Sauerstoff oder Umgebungsluft für 24, 48, 72 und 96 Stunden mit oder ohne Injektion einer niedrigen oder hohen Dose Paraquat (1,1′-Dimethyl-4,4′-bipyridium, PQ). Die Immunfärbung für LTx zeigte positive Reaktionen in den Neutrophilen. Diese zeigten eine zunehmende Verstärkung der Färbungsintensität in Abhängigkeit der Zeit in allen Gruppen mit Exposition von 100% Sauerstoff und in der Gruppe mit hoher Dose PQ, jedoch waren die positiven Befunde in der Gruppe mit Injektion nur niedriger Dose PQ schwach. Wir fanden die positive Immunfärbungsreaktion nicht nur in Neutrophilen, sondern auch in Alveolarmakrophagen. Dies zeigt, daß LTx sowohl von den Alveolarmakrophagen als auch von den Neutrophilen, abhängig von der Behandlungszeitdauer unter hyperoxischen Bedingungen, hergestellt wird, was dafür spricht, daß LTx ein wichtiger chemischer Mediator in Lungenerkrankungen ist.
    Notes: Abstract This paper investigates the immunohistochemical dynamics of leukotoxin (9,10-epoxy-12-octadecenoic acid, LTx) in the lungs of rats exposed to hyperoxia with or without paraquat. The rats were treated with 100% oxygen or ambient air for 24. 48, 72 and 96 h in the presence or absence of a low or high dose paraquat (1,1′-di-methyl-4,4′-bipyridinium, PQ) injection. Immunostaining for LTx demonstrated positive reactions in the neutrophils that showed a progressive increase in intensity of staining with time in all groups exposed to 100% oxygen and in the group with high dose PQ, but the positive findings were weak in the group injected with low dose PQ only. We found the positive immunostaining reaction not only in neutrophils but also in alveolar macrophages. This indicates that LTx is produced by alveolar macrophages as well as by neutrophils depending on the treatment period under hyperoxic conditions, suggesting that LTx is an important chemical mediator in pulmonary diseases.
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  • 6
    ISSN: 1432-1750
    Keywords: Immunohistochemistry ; l-arginine ; Nitric oxide ; Nonadrenergic noncholinergic nerve
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Bradykinin (10−8-10−5M) caused a concentration-dependent increase in cyclic GMP (cGMP) production in bovine tracheal smooth muscle in the absence of epithelium. The effect was calcium-dependent and was inhibited by pyrogallol (10 μM) and methylene blue (10 μM). The inhibition of pyrogallol was reversed by superoxide dismutase (100 Usnowml). Nitric oxide (NO) synthase inhibitors, N G-methyl-l-arginine (10–100 μM) and N G-nitro-l-arginine (10–100 μM) reduced cGMP accumulation induced by bradykinin in a concentration-dependent fashion, and the inhibition was reversed by l-arginine. Immunohistochemistry with a specific antibody against neuronal NO synthase from rat cerebellum showed positive staining localized in some nerve fibers. Bradykinin-induced cGMP accumulation appears to be related to the release of NO, part of which is probably synthesized in nonadrenergic noncholinergic nerve in bovine trachea.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Journal of comparative physiology 176 (1995), S. 425-435 
    ISSN: 1432-1351
    Keywords: FaRPs ; FMRFamide Nervous system Skeletal muscle ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract FMRFamide-related peptides of insects are particularly important because of their possible function as neurohormones and neuromodulators on a wide variety of tissues. Part of this study was an investigation of the immunofluorescent staining of motor nerves which arise in the metathoracic ganglion, examined in wholemount using an antiserum that recognizes extended -RFamide peptides (generally recognized to be of the FMRFamide family). This antiserum revealed immunochemical staining of numerous cell bodies in the metathoracic ganglion and of axons in peripheral nerve 5, a large nerve which contains both motor and sensory fibres. Axons staining positive for FMRFamide-related peptides were traced in nerve 5 as far as the femur-tibia joint, and into the first (sensory-motor) and third (motor only) ramus of nerve 5. Reverse-phase HPLC with radioimmunoassay revealed a peak of FMRFamide-related peptide activity in nerve 5 that was coincident with a peak found when thoracic ganglia were processed in the same fashion. A physiological assay was devised to test the ability of various non-native peptides to alter the characteristics of contraction of skeletal muscles of the legs. Using neurally evoked contractions of coxal depressor muscles of the metathoracic leg it was determined that several non-native peptides could potentiate muscle contractions. The results of this study suggest that muscles of the legs receive innervation by identifiable, FMRFamide-related peptide-containing neurons and that the release of peptide(s) at the muscle may be yet another method of modulating the mechanics of muscle contraction.
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  • 8
    ISSN: 1432-1351
    Keywords: Cobalt staining ; Gas chromatography-mass spectrometry ; Immunohistochemistry ; Insect ; Neuromodulation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract The two Protocerebral-Medulla 4 neurons (PM4a and b) in the locust brain have adjacent cell bodies in the medial deutocerebrum. They project through the posterior protocerebrum, forming limited arborisations en route, and enter the lobula and medulla of the ipsilateral optic lobe, where they form extensive, overlapping arborisations. The PM4a and b neurons are octopamine immunoreactive. Their octopamine content (approximately 25 pg per cell) is confirmed by gas chromatography-mass spectrometry; each cell contains approximately 25 pg p-octopamine. Simultaneous intracellular recording from exposed PM4a and b cell bodies reveals that the two cells are physiologically indistinguishable. They receive multimodal sensory inputs. Tactile/mechanosensory stimuli to much of the animal's body and head, acoustic stimuli, and simple visual stimuli all give rise to e.p.s.p.s and action potentials in the PM4 cell body. Simultaneous recording from the cell body in the deutocerebrum and the axon in the lobula demonstrates that action potentials are predominantly initiated in the deutocerebrum and propagate centrifugally, towards the optic lobe. Occasionally, bright light flashes will initiate an action potential in the axon in the optic stalk, which probably propagates bidirectionally: centripetally to the cell body, and centrifugally into the optic lobe. The extensive arborisations in the lobula and medulla are therefore likely to be sites of octopamine release. Because PM4 neurons are octopaminergic, project to the optic lobe, and receive modalities of sensory input known to dishabituate the Descending Contralateral Movement Detector (DCMD) visual interneuron, it is proposed that PM4 neurons are neuromodulatory — mediating dishabituation or arousal of the visual system.
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    International journal of legal medicine 107 (1995), S. 197-200 
    ISSN: 1437-1596
    Keywords: Macrophages ; Wound age ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Law
    Description / Table of Contents: Zusammenfassung Insgesamt wurden 117 vitale Hautwunden (Überlebenszeit wenige Sekunden bis 7 Monate), 20 postmortal gesetzte Verletzungen sowie Haut mit leichten bzw. fortgeschrittenen Fäulnisveränderungen untersucht und verschiedene Marker der Makrophagen-Differenzierung (27 E 10, RM 3/l, 25 F 9 und G 16/1) analysiert. Der „early stage inflammation marker” 27 E 10 färbte neben Makrophagen auch Monozyten und neutrophile Granulozyten, die innerhalb von Blutgefäßen bzw. in postmortal gesetzten Blutungen lokalisiert waren und liefert somit keine Informationen zum Wundalter, die über die Möglichkeiten des Routine-histologischen Nachweises von Makrophagen hinausgingen. Die von den Antikörpern RM 3/1 (intermediate stage inflammation marker) und 25 F 9 (late stage inflammation marker) erkannten Antigene wurden ausschließlich von Histiozyten und reaktiv eingewanderten Makrophagen exprimiert. Die morphometrische Analyse ergab positive Ergebnisse (definiert als ein mindestens zweifacher Anstieg der Zellzahl in zwei oder mehr Gesichtsfeldern verglichen mit der maximal feststellbaren Zahl an Histiozyten in unverletzter Haut) bei Verwendung der Antikörper RM 3/1 bzw. 25 F 9 frühestens 7 bzw. 11 Tage nach Wundsetzung. Ab 12 Tagen Wundalter reagierte der „chronic stage inflammation marker” G 16/1 erstmals positiv. Das Antigen ließ sich insgesamt allerdings in einem geringeren Prozentsatz der untersuchten Wunden darstellen. Vorteilhaft ist jedoch das Fehlen einer relevanten Expression durch Histiozyten, wodurch die Auswertung der Präparate erleichtert wird. Die entsprechenden Antigene lassen sich zudem in leicht - wenn auch in einer deutlich geringeren Färbeintensität -, aber nicht forgeschritten fäulnisveränderter Haut nachweisen, so daß deren immunhistochemische Darstellung gegebensfalls auch zur Beurteilung von länger überlebten Verletzungen an Leichen mit etwas fortgeschrittener Liegezeit herangezogen werden kann.
    Notes: Abstract A total of 117 vital skin wounds (post infliction intervals between a few seconds and 7 months), 20 postmortem wounds and skin specimens with beginning or advanced signs of putrefaction were investigated. Different markers for macrophage maturation (27 E 10, RM 3/1, 25 F 9, G 16/1) were analyzed by immunohistochemistry. The early stage inflammation marker 27 E 10 stained macrophages, but also monocytes and neutrophilic granulocytes localized in blood vessels or bleeding induced postmortem and therefore provided no further information for a forensic wound age estimation in comparison to the routine histological detection of macrophages. The antigens recognized by the RM 3/1- (intermediate stage inflammation marker) and 25 F 9-antibodies (late stage inflammation marker) were expressed exclusively by histiocytes and inflammatory cells that had migrated from the blood vessels as part of the acute inflammatory response associated with an intravital reaction. The morphometrical analysis revealed positive results (defined as at least a two-fold increase in number in 2 or more microscope fields when compared to the maximum value of histiocytes found in uninjured skin) for the RM 3/1- or 25 F 9-antibody earliest in wounds aged 7 or 11 days, respectively. Similarly to the 25 F 9-antibody, the chronic stage inflammation marker (G 16/1) reacted with a macrophage subpopulation first detectable 12 days after wounding but showed positive results in a comparably reduced percentage of cases. On the other hand, this marker did not stain a relevant number of resident macrophages thus facilitating the evaluation of the specimens. The markers 27 E 10, RM 3/1 and 25 F 9 are also useful for the evaluation of slightly - even though the staining intensity was considerably reduced - but not advanced putrefied skin. Therefore, the immunohistochemical analysis of the corresponding antigens can possibly contribute to an age estimation of wounds with advanced post infliction intervals obtained from corpses with longer - but limited - postmortem intervals.
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  • 10
    ISSN: 1437-9813
    Keywords: Rhabdomyosarcoma ; Enzyme immunoassay ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Four proteins, the α-subunit of S100 protein (S100-α), carbonic anhydrase III (CA-III), the β-subunit of enolase (EN-β), and the M-subunit of creatine kinase (CK-M), are characteristic of skeletal muscle tissue or components. Histochemical studies of human skeletal muscle fibers have shown that S100-α and CA-III are localized in type 1 fibers, EN-β in type 2 fibers, and CK-M in both fibers. These four proteins were evaluated as markers for rhabdomyosarcoma by enzyme immunoassay and immunohistochemistry. Concentrations of EN-β and CK-M were significantly higher in rhabdomyosarcoma than in neuroblastoma or Wilms' tumor. Staining for S100-α and CA-III was limited to tumor cells with abundant eosinophilic cytoplasm in most rhabdomyosarcomas. EN-β and CK-M staining was also found in several small, round and short, spindle-shaped tumor cells. S100-α, CA-III, EN-β, and CK-M were demonstrated immunohistochemically in 4 (27%), 7 (47%), 14 (93%), and 12 (80%) of 15 rhabdomyosarcomas, respectively. Our results indicate that EN-β is the most useful marker among the four proteins for diagnosing rhabdomyosarcoma.
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  • 11
    ISSN: 1432-2307
    Keywords: Ovarian carcinoma ; p53 ; Sex steroid receptor ; Immunohistochemistry ; Heat shock protein 72
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Mutations of the tumour suppressor p53 gene have been reported in a variety of human malignant tumours, and are frequently associated with overexpression of p53 protein. To examine the significance of p53 gene alteration in malignant epithelial tumours of the ovary, we studied the immunohistochemical reactivity with a monoclonal antibody against p53 (PAb 1801) in 6 ovarian tumours of low malignant potential (LMP) and 32 ovarian carcinomas. The existence of any correlation of p53 overexpression with the clinicopathological features and with the immunohistochemical expression of 72 kDa heat shock protein (HSP72) and sex steroid receptors (oestrogen receptors; ER, progesterone receptors; PR) was also analysed. Expression of p53 was found in 2 of the 6 (33.3%) LMP tumours and in 15 of the 32 (46.9%) carcinomas. Strong expression of HSP72 was observed in 11 of the 17 (64.7%) p53-positive tumours, but only in 2 of the 21 (9.5%) p53-negative ones. Histologically, p53-positivity was observed in 7 of the 10 (70%) serous carcinomas, 4 of the 6 (66.7%) mucinous, 4 of the 10 (40%) endometrioid, and none of the 4 clear cell and 2 transitional cell carcinomas. Distribution of p53-positive cells in the tumour sections was homogenous in serous tumours, but heterogenous in mucinous lesions. All of the 4 carcinomas arising in endometriotic cysts were p53-negative. These differences support the thesis of heterogeneity in ovarian carcinogenesis. There was an inverse relationship between p53-positivity and sex steroid receptor status for ovarian carcinomas; 14 of the 15 p53-positive carcinomas were negative for both ER and PR, whereas 11 of the 17 p53-negative carcinomas were positive for ER and/or PR (P〈0.01).
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  • 12
    ISSN: 1432-2307
    Keywords: Placental-type glutathione S-transferase ; Human skin ; Squamous cell carcinoma ; Northern blotting ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The expression of human placental-type glutathione S-transferase (GST-π) was investigated in human cutaneous squamous cell carcinoma (SCC) and normal skin using Northern blot and immunohistochemical analysis. In Northern blot examination, the expression of GST-π transcript was recognized in all instances, and SCC showed a significantly higher expression of GST-π than normal skin. In immunohistochemical examination, GST-π was stained well in the cytoplasm of all cells of the stratum granulosum, many cells of the stratum spinosum and a few cells of the stratum basale in normal skin. Some cells of the stratum spinosum and almost all cells of the stratum basale showed only a weakly positive or almost negative reaction for GST-π. No nuclear staining of GST-π was obvious in normal epidermal cells. In SCC, many cells showed strong positivity for GST-π in the cytoplasm, and some were obviously accompanied by nuclear staining of GST-π. These findings suggest that GST-π exists mainly in many cells in the upper layers of the normal epidermis and that GST-π is involved in the process of carcinogenesis.
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  • 13
    ISSN: 1432-2307
    Keywords: Testicular neoplasms ; Testicular carcinoma in situ (CIS) ; Globotriaosylceramide (Gb3) ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Changes in the cell membrane glycolipid composition and metabolism are frequently associated with carcinogenesis. The accumulation of globo-series glycolipids is the most notable change of the germ cell glycolipid composition observed in testicular tumours. In this study, the expression of the globo-series core-structure, globotriaosylceramide (Gb3) was investigated in the preinvasive stage of testicular germ cell tumours, carcinoma in situ (CIS). Seventeen tissue specimens with CIS and 12 samples of overt testicular tumours were immunostained with anti-Gb3 monoclonal antibody 38-13. The accumulation of Gb3 was detected in 12 CIS samples (70.6%) and in 8 invasive tumour samples (66.7%), including seminoma, non-seminoma and a combined germ cell tumour. Our findings indicate that the composition of glycolipids shift at the common preinvasive stage of testicular germ cell tumours and confirm that Gb3 is a tumour-associated antigen of testicular germ cell neoplasia.
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  • 14
    ISSN: 1432-2307
    Keywords: Chromogranin A ; Chromogranin B ; Secretogranin II ; Secretoneurin ; Neuroendocrine tumours ; Gastrointestinal tract ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The aim of the present study was to investigate immunohistochemically the distribution of chromogranin A, chromogranin B, and secretogranin II in a series of 152 neuroendocrine tumours of the gastrointestinal tract. Tumour tissues from 25 argyrophil gastric carcinoids, 18 gastrin and 5 somatostatin-producing tumours, 4 ‘gangliocytic paragangliomas’, 49 classical argentaffin and 2 L cell appendiceal carcinoids, 27 classical ileal carcinoids, 17 rectal carcinoids, and 5 poorly differentiated neuroendocrine tumours of the stomach and rectum were immunostained with antibodies against chromogranin A, chromogranin B, and secretogranin II. Chromogranin A was the major granin expressed in gastric carcinoids and in serotonin-producing carcinoids of the appendix and the ileum. In contrast, strong chromogranin B and secretogranin II immunoreactivity was found in rectal carcinoids, in which chromogranin A was rarely expressed. Since chromogranin A is a widely used marker for neuroendocrine differentiation, it is of diagnostic importance that some gastrin-producing tumours, ‘gangliocytic paragangliomas’, poorly differentiated neuroendocrine carcinomas, and appendiceal L cell carcinoids completely lacked chromogranin A positivity. It is concluded that the various neuroendocrine tumours of the gastrointestinal tract show distinctly different patterns of granin expression, probably reflecting their histogenetical origin.
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  • 15
    ISSN: 1432-2307
    Keywords: Gastric cancer ; p53 tumour-suppressor gene ; Mutation spectrum ; Dietary mutagens ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The p53 tumour-suppressor gene plays an important role in gastric carcinogenesis. In an analysis of the spectrum of mutations of the p53 gene seen in 56 primary gastric carcinomas of various types and grades of differentiation, the entire coding sequence (exons 2–11) of the p53 gene was screened by single-strand conformation polymorphism analysis and direct genomic sequencing of polymerase chain reaction products. Intragenic restriction site polymorphisms and the probe YNZ22 were used for the detection of loss of heterozygosity (LOH) of the p53 gene locus on chromosome 17p. p53 overexpression was studied with the anti-p53 antibody CM-1. A total of 21 somatic alterations of the p53 gene were found. Twenty were base-pair substitutions, and one was an eight base-pair deletion. Six tumours with p53 mutations revealed LOH. Abnormalities in p53 expression were found in 17 tumour samples, of which 16 had gene mutations. The spectrum of mutations observed was consistent with the predicted spectrum for dietary mutagens associated with the metabolism of nitrogenous compounds, resulting in deamination of nucleic acids. Our findings suggest that p53 could be a primary target for mutations associated with dietary carcinogens in gastric carcinogenesis.
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  • 16
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 426 (1995), S. 457-460 
    ISSN: 1432-2307
    Keywords: Immunohistochemistry ; Endocervix ; Uterine stromal tissues
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract CD34 is a myeloid progenitor cell antigen present in endothelial cells and some other mesenchymal cells, including perivascular and periadnexal dermal fibroblasts. It was evaluated immunohistochemically in uterine stromal tissue and in 4 aggressive angiomyxomas and 6 endometrial stromal sarcomas with potentially related and similar stromal tissues. The stromal cells in normal endocervix and endocervical polyps were strongly CD34 positive irrespective of the cycle phase, and negative for muscle actins. Ectocervical stroma was variably but generally less CD34 reactive. In the endometrium, the CD34 reactivity was limited to the stromal cells of the basal endometrium and was found only in 4 of 20 from proliferative endometria and 1 of 8 from secretory endometria. The uterine cervical and myometrial smooth muscle tissues showed CD34 positive cells only between the muscle bundles and around the vessels. In pelvic aggressive angiomyxomas and endometrial stromal sarcomas the tumour cells were CD34 negative and only the vascular endothelial cells were positive. Endothelial cell-specific antigen, CD31, was identified only in endothelial cells and was not present in the endocervical stroma. These results illustrate the particular immunohistochemical profile of endocervical stromal tissue, namely the strong CD34 expression. The CD34 reactivity of the endocervical tissues should be noted and not confused with neoplasms known to be strongly CD34 positive, such as angiosarcomas, Kaposi's sarcomas and some other spindle cell sarcomas.
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  • 17
    ISSN: 1432-2307
    Keywords: Cathepsin D ; pS2 ; Heat shock protein 27 ; Immunohistochemistry ; Breast cancer
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Determination of steroid receptors and several oestrogen-regulated proteins in mammary carcinomas is useful in the prediction of their evolution and of the likely success of endocrine therapy. Cathepsin D (Cat D), pS2 peptide and heat shock protein 27 (Hsp 27) were detected immunohistochemically in 63 infiltrating ductal (NOS) breast carcinomas, and our results were qualitatively correlated with several clinicopathological indicators and patients' overall survival. Cat D immunostaining of tumour cells was strongly associated with axillary nodal involvement (P f=0.0005) and so, it is directly connected with the metastatic capacity of malignant cells. pS2 immunoreactivity was correlated with oestrogen and progesterone receptor positivity (P f=0.0009 and P f=0.05 respectively) and, nonsignificantly, with good differentiation of the tumours (P f=0.06). Neoplastic cells expressing this protein are therefore characterised by a highly organised state of cellular physiology. Hsp 27 was expressed predominantly in tumours with one to four infiltrated lymph nodes (P t=0.05), and Hsp 27-positive patients were inclined to rather short survival, possibly due to chemotherapy resistance. In future, prognostic estimation of each one of the examined markers should be performed in specific large subgroups of patients. The findings of this study contribute to the establishment of criteria by which these subgroups should be formed.
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  • 18
    ISSN: 1432-2307
    Keywords: Myolipoma ; Soft tissue ; Round ligament ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Tumours consisting of a mixture of mature adipose and smooth muscle tissues, including those designated lipoleiomyomas, fibrolipoleiomyomas and myolipomas, are exceedingly rare, but most often occur in the uterine corpus. We describe here a case of such a tumour arising in the right round ligament of a 44-year-old woman. The tumour, which measured approximately 20×15×10 cm, was well encapsulated and did not involve the intrapelvic organs. Intricate mixtures of adult adipose tissue and bland smooth muscle exhibited no cellular atypia or nuclear mitotic figures, and there was little vascular proliferation. We diagnosed the lesion as a myolipoma of soft tissue with dual differentiation, and have found only 13 cases of this tumour including our own in the English literature. The present tumour is the first reported in the round ligament. Although this tumour is rare, its recognition is important for the avoidance of erroneous diagnoses.
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  • 19
    ISSN: 1432-2307
    Keywords: Lymphoma ; Hodgkin's disease ; Polymerase chain reaction ; Immunohistochemistry ; Histological classification
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Ninety-one Hodgkin's lymphomas (HD), 52 non-Hodgkin lymphomas (NHL) and 33 specimens of non-neoplastic lymphatic tissues were investigated by polymerase chain reaction (PCR) for the presence of the bcl-2/JH gene rearrangement. The majority of the HD cases were drawn from the files of the German Hodgkin trial where diagnoses are established by a panel of four independent histopathologists. Using the very sensitive PCR method which detected 1 positive among 10000 negative cells, the bcl-2/JH gene rearrangement was found in 7/52 NHL and 3/16 tonsils with follicular hyperplasia, but in none of the 91 HD. The bcl-2 protein, however, was expressed by malignant cells of B and T cell lymphomas and by the giant tumour cells in 2/13 HD lymphocyte predominant, 11/28 HD nodular sclerosing I, 14/17 HD nodular sclerosing II, 10/27 HD mixed cellularity and 3/3 HD lymphocyte depleted. The bcl-2/JH rearrangement is thus independent of protein over-expression, the latter being found in all types of lymphomas. Our results do not confirm the findings of others who have detected the bcl-2/JH rearrangement in HD. These discrepancies may be explained by differences in choice of material, the gene rearrangement actually occuring in bystander cells but not in Reed-Sternberg or Hodgkin cells, or by contamination.
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  • 20
    ISSN: 1432-2307
    Keywords: Small round blue cell sarcomas ; Integrins ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Integrins are a large and complex family of membrane spanning αβ heterodimeric cell surface glycoproteins mediating cell/cell and cell/matrix interactions. Small, round, blue cell sarcomas (SRBCS) are a group of poorly differentiated tumours of various and in part uncertain histogenesis displaying similar cytomorphology. Among them are rhabdomyosarcomas (RMS), ganglioneuroblastomas [(G)NB], primitive peripheral neuroectodermal tumours (pPNET) and Ewing's sarcomas (ES). Thirty-two SRBCS were studied immunohistochemically for the distribution of β1, β3 and β4 integrins in situ. We found complex and to some extent differential patterns of β1, β3 and β4 integrin subunit expression in different types of SRBCS: all of the sarcomas studied were consistently β1+, β4−, α2−. Four of nine RMS were completely negative for all other integrin subunits studied while one RMS was α5+ throughout and three RMS were focally α5+. Three RMS expressed the α6 and αv chains. In contrast to RMS, pPNET and ES, all of which were α1−, α3−, (G)NB were α3+ and frequently co-expressed α1. The eight pPNET and seven ES studied showed a similarily restricted integrin profile that was limited to the expression of β1 and α5 in nearly all cases. In summary, RMS were β1+, α1−, α3− and heterogeneously expressed α5 and α6. (G)NB were generally β1+, α1+, α3+, α5−, α6−. pPNET and ES were β1+, α1−, α3−, α5+, α6−. The data illustrate a complex expression pattern of various integrins in SRBCS, a differential expression pattern of some of the integrin subunits among different types of SRBCS and almost identical integrin profiles in pPNET and ES.
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  • 21
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    Virchows Archiv 426 (1995), S. 69-76 
    ISSN: 1432-2307
    Keywords: Phosphoprotein B-50 (growth-associated protein GAP-43) ; N-CAM ; Vimentin ; Immunohistochemistry ; Human skeletal muscle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The growth-associated protein B-50, also termed GAP-43, is a membrane-bound phosphoprotein that is expressed in neurons. It is particularly abundant during periods of axonal outgrowth in development and regeneration of the central and peripheral nervous system. In this paper we study the expression of B-50 in inflammatory and dystrophic myopathies. To investigate the state of regeneration, N-CAM and vimentin serial sections were performed, because N-CAM and cytoskeletal protein vimentin are excellent markers for regenerating muscle. Light-microscopic evaluation showed that muscle fiber regeneration in myopathies corresponds closely to B-50 immunoreactivity in satellite cells, myoblasts, myotubes and small regenerating myocytes in cytoplasmatic distribution. In normal muscle and in biopsies of neurogenic muscular atrophy, however, no light-microscopically demonstrable B-50 staining was found. B-50 in muscles apparently plays a role in the growth morphology of regenerating myocytes, and the phosphoprotein B-50 can no longer be regarded as a neuron-specific molecule.
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  • 22
    ISSN: 1432-2307
    Keywords: Ito cell ; Fulminant hepatitis ; Postnecrotic fibrosis ; α-Smooth muscle actin ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract To examine the relationship of Ito cells to postnecrotic liver fibrosis, liver specimens, obtained at autopsy from 17 patients with acute massive necrosis (AMN) and acute submassive hepatic necrosis (ASMN), were examined immunohistochemically. In normal adult livers, Ito cells positive for α-smooth muscle actin isoform (ASMA) were rarely seen, scattered along hepatic sinusoids. In contrast, in AMN the Ito cells in necrotic areas became strongly positive for ASMA. They were swollen with elongated cytoplasmic processes along collapsed sinusoidal walls. Around these ASMA-positive Ito cells, there were numerous infiltrated macrophages and lymphocytes present. There was no significant alteration of fibroblasts in the portal tracts. In the middle and late stages of ASMN, the spindle-shaped ASMA-positive Ito cells formed a continuous cellular network. New fibre formation was predominantly around them. In this immediate postnecrotic fibrosis, ASMA-positive stromal cells of Ito cell origin were distributed irregularly and were closely associated with reticulin and newly-formed collagen fibres. Regenerative nodules were surrounded by dense layers of ASMA-positive stromal cells. Throughout the stages of ASMN, portal fibroblasts remained negative for ASMA. We believe that Ito cells in necrotic areas show myofibroblastic transformation and play a central role in the postnecrotic liver fibrosis. Portal fibroblasts play no significant part in this type of fibrosis.
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  • 23
    ISSN: 1432-2307
    Keywords: CYP2E1 ; Immunohistochemistry ; Pulmonary carcinoma
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Cytochrome P450 2E1 (CYP2E1) is a major xenobiotic-metabolizing enzyme but data concerning its extrahepatic expression are few. CYP2E1 can metabolically activate many procarcinogens and therefore its presence in the lung might play a role in bioactivation of procarcinogens, so we studied the expression and localization of CYP2E1 in primary pulmonary carcinomas and surrounding normal bronchial tissue from 28 patients. Seromucous glands showed expression of CYP2E1 in 19 and bronchial epithelium in 18 of the 28 samples of normal bronchial tissue. Thirteen of the corresponding cases of primary pulmonary carcinoma showed staining for CYP2E1. In 11 of these 13 cases, CYP2E1 was also present in normal bronchial tissue. There was no statistically significant difference in the expression of CYP2E1 between adenocarcinomas and squamous cell carcinomas. No association was observed between the expression of CYP2E1 in tumour tissue and normal bronchial tissue. However, there was a significant correlation between the expression of CYP2E1 in seromucous glands and bronchial epithelium (r=0.61, P〈0.01) of normal tissue. We conclude that CYP2E1 can be present in both normal and neoplastic bronchial tissue.
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  • 24
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    Virchows Archiv 426 (1995), S. 523-528 
    ISSN: 1432-2307
    Keywords: Von Hippel-Lindau disease ; Neuroendocrine tumour ; Electron microscopy ; Flow cytometry ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract A 21-year-old woman with a family history of von Hippel-Lindau disease presented with a mass in the head of the pancreas. Light microscopic features of the tumour suggested neuroendocrine differentiation and although it displayed positive immunostaining for the antigens expected in a neuroendocrine neoplasm, S-100 staining was also present. This unusual feature prompted further evaluation by routine and post-embedding protein-A gold immunoelectron microscopy, which demonstrated the presence of neuroendocrine granules. Tumour cell DNA content was normal by flow cytometry. Although this patient exhibited no other signs of von Hippel-Lindau disease, the presence of a pancreatic tumour with neuroendocrine differentiation demonstrated that she was affected. Future surveillance and genetic counselling will be influenced by this diagnosis.
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  • 25
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    Virchows Archiv 426 (1995), S. 571-575 
    ISSN: 1432-2307
    Keywords: Retinoblastoma ; Immunohistochemistry ; Rb protein ; p53
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The immunohistochemical features of 24 retinoblastoma specimens from 22 patients, 15 with unilateral and 7 with bilateral disease, were examined by the labelled streptavidin biotin (LSAB) method and compared with those of specimens from the remaining morphologically normal retina. In the normal retina, S-100 protein, glial fibrillary acidic protein (GFAP) and vimentin were detected in astrocytes and/or Müller cells. Neurofilament protein was seen in axons of the ganglion cells, synaptophysin was present in both plexiform layers, bcl-2 oncoprotein was seen in ganglion cells and bipolar cells, and neuron-specific enolase (NSE) was detected in ganglion cells, bipolar cells and photoreceptor cells and in their cell processes. While retinoblastoma (Rb) protein expression was noted in ganglion cells, bipolar cells, and some photoreceptor cells, p53 protein was not expressed at all. In all retinoblastomas, strong NSE expression and weak bcl-2 expression was observed in almost all tumour cells and synaptophysin was localized in rosette-forming cells, while tumour cells were devoid of S-100, GFAP, vimentin and neurofilament protein. These findings support the view that retinoblastomas are composed of neuron-committed cells. In addition, no Rb protein expression was detected in retinoblastomas, whereas p53 expression was found in 18 cases (75%).
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  • 26
    ISSN: 1432-2307
    Keywords: Kidney tumours ; Tumour suppressor gene ; Immunohistochemistry ; SSCP
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract P53 tumour suppressor gene expression was estimated immunohistochemically using DO-1 monoclonal antibody (recognising both wild-type and mutant p53) in 88 human renal tumours. Single strand conformation polymorphism (SSCP) analysis of possible mutations within exons 4–8 of the p53 gene was performed in 29 of the tumours (mostly immunostaining-positive cases). Obviously elevated p53 content was detected with DO-1 antibody in chromophobic cell carcinomas and most clear/chromophilic cell tumours (in chromophilic cell populations). In contrast, clear cell carcinomas demonstrated either complete absence of p53 expression or the presence of single immunopositive nuclei. Oncocytomas were completely negative. Additional immunostaining of the positive samples with mutant p53-specific Pab240 monoclonal antibody failed to detect immunopositive material. No p53 mutation was found in any of the samples analysed by SSCP. Our results suggest that the elevated p53 content in human renal cell carcinomas does not result from gene mutation and that p53 gene alterations are probably not an important mechanism in the development of human renal cell carcinomas. Accumulation of the wild-type p53 protein may be a useful prognostic marker indicating neoplastic progression and malignancy.
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  • 27
    ISSN: 1432-2307
    Keywords: p53 ; Ki-ras ; Gastric carcinoma ; Immunohistochemistry ; Polymerase chain reaction-single-strand conformational polymorphism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract With the aim of detecting the timing of p53 and Ki-ras gene alterations in the gastric adenoma-carcinoma sequence, 19 early gastric adenocarcinomas arising from adenomas were studied. Immunohistochemically, 5 adenocarcinomas were positive for p53; 3 focally and 2 diffusely. The p53 point mutations were detected in a focal area with p53 immunoreactivity in 2 of the 5 p53-positive adenocarcinomas. This indicated that p53 point mutations may play a less crucial part in malignant conversion of adenoma to adenocarcinoma in the stomach than in the colon. No Ki-ras gene mutations at codons 12 and 13 were detected in any lesion. These results suggest that the adenoma-carcinoma sequence in the stomach has a different mechanism from that in the colon.
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  • 28
    ISSN: 1432-2307
    Keywords: Langerhans cell ; Histiocytosis ; Human ; Immunohistochemistry ; GM-CSF receptor ; CDw116
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Langerhans' cell histiocytosis (LCH) is characterized by the proliferation of large mononucleated cells containing Birbeck granules and expressing CD1a. Recent studies have demonstrated that LCH is a clonal proliferation; however, its aetiology is still unknown. Growth and differentiation of bone-marrow-derived cells are controlled by cytokines. The proliferation, differentiation and activation of normal Langerhans cells are controlled by granulocyte/macrophage colony-stimulating factor (GM-CSF) in vitro. Therefore, GM-CSF could be implicated in the pathogenesis of LCH. Indeed, LCH cells contain GM-CSF, and children with disseminated LCH have an elevated GM-CSF serum level. As a cytokine only acts on cells expressing a specific receptor, we investigated the presence of GM-CSF receptor on LCH cells. Fourteen frozen tissue samples from children with LCH were studied by in situ immunohistochemistry with two mouse monoclonal antibodies specific for the α chain of the GM-CSF receptor (CDw116). LCH cells of all the samples were positively stained with both antibodies. This study suggests that GM-CSF may be a growth factor for LCH cells.
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  • 29
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    Virchows Archiv 427 (1995), S. 229-241 
    ISSN: 1432-2307
    Keywords: p53 ; Immunohistochemistry ; Human tumours
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract p53 aberrations are the most common genetic alteration found in human tumours and this review summarizes the current understanding of the clinical significance of p53 abnormalities. Immunohistochemical and molecular techniques can demonstrate alterations at the protein and gene level, respectively, but with a significant discordance between the findings of either technique. The tumours evaluated in this review include cancers of the breast, lung, gastrointestinal tract, genitourinary tract, and others. In most cases, only data on p53 protein are available and in each of these tumour types discrepant conclusions on the clinical value of p53 abnormalities as prognostic indicators have been reached. The role of p53 in the context of anticancer adjuvant therapy has also been analysed. Experimental data suggest that p53 affects the apoptotic response to anticancer agents, but this has not yet been proven in a clinical series where this demonstration and its effect on therapy could represent one of the most important endpoints in p53 clinical research. The use of standardized techniques to evaluate p53 gene mutation and protein accumulation within controlled clinical series of patients entering prospective trials is essential to answer the many remaining questions on the clinical significance of p53 aberrations.
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  • 30
    ISSN: 1432-2307
    Keywords: Indirect immunoperoxidase staining ; Tissue section ; Fungi ; Immunohistochemistry ; Polyclonal antibody
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract This study was performed to identify pathological fungi of eight species [Aspergillus fumigatus, Candida albicans, Torulopsis (Candida) glabrata, Cryptococcus neoformans, Fusarium anthophilum, Rhizopus oryzae, Sporothrix schenckii and Trichosporon beigelii] in formalin-fixed, paraffin-embedded tissue sections by indirect immunoperoxidase staining. Mature albino rabbits were immunized with formalin-killed organisms. Antibodies were prepared by precipitation. Immunoperoxidase staining was applied to the paraffin-embedded tissue sections of experimentally infected mice and human autopsy and surgical specimens. Although the cell walls of each fungus stained clearly, many cross-reactivities appeared. However, it was possible to obtain specificity for the eight species by absorption and dilution of the antisera.
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  • 31
    ISSN: 1434-0879
    Keywords: mdm-2 protein ; Immunohistochemistry ; Bladder carcinoma ; p53 protein
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Amplification of the mdm-2 gene and overexpression of the mdm-2 protein might inactivate p53 function, and may have prognostic relevance. The present paper investigated the immunohistochemical overexpression of the mdm-2 and p53 proteins in 25 biopsy specimens of transitional cell bladder carcinomas (10 pT1 and 15 pT2 or higher stages). Five cases (20%) showed strong mdm-2 protein immunoreactivity in more than 5% of the tumor cells; 14 cases (56%) showed p53 immunoreactivity in more than 20% of the cells, and were considered as overexpressing p53 protein. Four of the five cases with strong mdm-2 immunoreactivity did not show p53 overexpression, and 13 of the 14 cases with p53 overexpression did not show mdm-2 immunoreactivity. Our data are consistent with the hypothesis that p53 overaccumulation (and hence possible p53 gene mutation) or mdm-2 overexpression (and hence possible mdm-2 gene amplification) may mirror two different and possibly complementary gene alterations, which might finally interfere with the control of cell proliferation and apoptosis. In this perspective, evaluation of the combined mdm-2/p53 protein phenotype in human bladder carcinomas could have prognostic relevance and give us better prognostic information than evaluation of the p53 protein alone.
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  • 32
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    Urological research 23 (1995), S. 189-192 
    ISSN: 1434-0879
    Keywords: Ureterovesical junction ; Nitric oxide ; Innervation ; Immunohistochemistry ; Human
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Nitric oxide synthase (NOS) immunohistochemistry and nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) histochemistry were used to investigate the distribution of nitroxergic, i.e., nitric oxide-synthesizing, neuronal perikarya and processes in the human ureterovesical junction (UVJ). Tissue specimens obtained from two cadaver kidney donors and two patients undergoing radical cystectomy for bladder cancer were examined. Clusters of NOS-immunoreactive neurons were localized in extramural ureterovesical ganglia. NOS-containing nerve fibers traveled within large extramural nerve trunks and marched among smooth muscle bundles. Extramural and intramural blood vessels were encircled by varicose NOS-positive axonal processes. The distribution of NOS immunoreactivity paralleled the staining pattern for NADPH-d activity. Urothelium stained strongly for NADPH-d activity but showed no NOS immunolabeling. Specimens from all four patients investigated showed similar staining patterns. Our results suggest that nitric oxide, a potent smooth-muscle-relaxing neurotransmitter in the autonomic nervous system, plays a physiologic role in opening the human UVJ.
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  • 33
    ISSN: 1432-0533
    Keywords: Key words Pick body ; Lewy body ; Locus ceruleus ; Pick's disease ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We observed abundant Pick argentophilic inclusion bodies (PBs) as well as some atypical Lewy bodies (LBs) in the locus ceruleus (LC) from a patient with Pick's disease. In addition, there were a few neurons which contained both PBs and LBs. PBs in the LC frequently appeared multiple and had lobulated or irregular shapes, though their ultrastructural elements were the same as those of the PBs appearing in the cerebral cortex, and consisted of randomly arranged smooth-surfaced straight tubules of 15 nm in diameter, mixed with a small number of long-period constricted fibrils. The ultrastructure of the LB coexisting with PB was identical with that previously reported; a dense core was surrounded by concentric layers of radially oriented 10-nm filaments and was clearly distinguishable from the PB. Immunohistochemical examination with various antibodies related to neurofibrillar pathology demonstrated that anti-tau antibodies reacted positively with both PB and the rim portion of LB in the present case; an unusual finding for LB. The anti-neurofilament 200-kDa protein stained only LBs, even when PBs and LBs coexisted in the same neuron. These findings show that two kinds of neuronal fibrillar inclusions, whose underlying cytoskeletal abnormalities are thought to be different, can coexist in the same neuron. In addition, the formation of multiple, lobulated PBs may suggest some particularity of cytoskeletal composition of the LC neurons.
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  • 34
    ISSN: 1432-0533
    Keywords: Key words Alzheimer's disease ; Neurofibrillary ; tangles ; Amyloid ; Ultrastructure ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Senile plaque and paired helical filament (PHF) formation are characteristic of Alzheimer's disease, but the mechanisms leading to these lesions still remain unclear. To understand them better, we have performed different immunolabellings of amyloid protein and PHF. We describe a very specific immunodetection of PHF with AD2, a monoclonal antibody directed against a hyperphosphorylated epitope of PHF-tau, and use double immunolabelling to show that PHF and plaque amyloid are discretely labelled by different antibodies. We also discuss different mechanisms of PHF maturation.
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  • 35
    ISSN: 1432-0533
    Keywords: Key words Alzheimer's disease ; Senile plaques ; Microglia ; Lysosomes ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract One of the major histopathological lesions in brains of patients with dementia of the Alzheimer type (DAT) is the senile plaque. Although previous studies have shown that senile plaques are often accompanied by microglial cells, the role of these cells in DAT pathology is still unclear. In an immunohistochemical and immuno-electron microscopical analysis of DAT and control brain tissues we addressed this issue using two monoclonal antibodies (mAbs KP1 and 25F9) directed against lysosomal antigens in monocytes and macrophages. Whereas KP1 stained lysosomes in both resting and activated microglial cells, 25F9-staining was predominantly found in lysosomes of activated microglial cells in classic senile plaques. The number and size of 25F9-positive lysosomes in activated microglial cells was increased compared to 25F9-staining in unaffected areas in DAT and control sections. We conclude that mAb 25F9 is a unique and useful lysosomal marker, with a higher specificity than other known markers, for activated microglial cells associated with classic, but not with diffuse, senile plaques.
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  • 36
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    Acta neuropathologica 91 (1995), S. 23-30 
    ISSN: 1432-0533
    Keywords: Key words Protoplasmic astrocyte ; Secondary ; lysosome ; Immunohistochemistry ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract By hybridizing mouse myeloma cells with spleen cells from a BALB/c mouse immunized with the glial cell-rich fraction prepared from an autopsied human brain, we established a hybridoma that produces a monoclonal antibody to protoplasmic astrocytes (PA). The antibody, named PRAS-1, consistently labeled cytoplasm of PA with a granular pattern. In a few cases, the cytoplasmic processes of several astrocytes in gray and white matter were also stained. The immunoreactivity was lost after periodic acid treatment or methylation, showing that the epitope is composed of a carbohydrate. The cytoplasmic reaction was resistant to protease digestion and lost after incubation in an organic solvent, suggesting that a glycolipid is the antigen. On the other hand, the reaction in the processes disappeared upon protease digestion. Ultrastructurally, the immunoreaction was localized to secondary lysosomes. Cross-reactivity was noted on a small number of incidental neurons, corpora amylacea, hepatocytes and esophageal epithelial cells. A long period of formalin fixation did not deteriorate the antigenicity. PRAS-1 was demonstrated to detect PA immunohistochemically on paraffin sections, and may be applicable to further investigations into development or neoplasms of human astrocytes.
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  • 37
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    Anatomy and embryology 192 (1995), S. 21-33 
    ISSN: 1432-0568
    Keywords: TGF β ; Retinoid ; Immunohistochemistry ; In situ hybridization ; Mouse embryogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract In a previous study we investigated the effects of RA excess on TGF β protein localization in early postimplantation stages of mouse development. Here we extend this investigation by comparing the effects of retinoid deficiency with those of excess, and by comparing the effects of altered retinoid status on TGF β protein and RNA transcript distribution. In vitamin A-deficient embryos, TGF β1 RNA and protein distribution were both unaltered compared with controls; conversely, TGF β2 protein levels were reduced while RNA levels remained normal. In RA-treated embryos, the previous study showed that intracellular TGF β1 levels were decreased, while those of extracellular TGF β1 were initially decreased but subsequently increased; here we found that TGF β1 RNA transcript levels were reduced following exposure to RA excess. TGF β2 showed a clear disparity between the effects of RA excess on protein and RNA transcript levels: RNA transcript distribution was unchanged or showed a slight increase in RA-treated embryos, whereas the previous results showed greatly reduced protein levels. The new results provide further evidence for interaction between retinoids and TGF βs during mouse development, and indicate that retinoids are capable of differentially regulating TGF β isoforms through mechanisms involving different stages in the process of TGF β synthesis and secretion. The long-term nature of the effects of transient exposure to RA excess suggests that the mechanisms of RA-TGF β interaction may be indirect.
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  • 38
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    Anatomy and embryology 192 (1995), S. 107-115 
    ISSN: 1432-0568
    Keywords: Immunohistochemistry ; Neuropeptide ; Axon reflex ; Vasomotion ; Peripheral sensory fiber
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We investigated the development of substance P immunoreactivity in mouse vomeronasal organs in embryos, juveniles, and adults. In all stages, substance P fibers were found in the receptor-free epithelial area, but never in the neuroepithelium. Substance P fibers were found sparsely in the lamina propria of 15-day-old embryos. Although buds of the vomeronasal glands in the cavernous tissue were observed in 17-day-old embryos, and gradually grew in size and numbers, the substance P fibers around them decreased after about the 13th day. Thus, substance P may be a trophic factor for the development of the vomeronasal glands in the cavernous tissue. We first recognized substance P fibers reaching the surface of the receptor-free epithelium in 13-day-old pups. In 21-day-old mice, substance P fibers were as well developed as in adult mice. Considering the development of the substance P fibers in the receptor-free epithelium and the cavernous tissue, they probably cause the vasodilation of the cavernous tissue via local axon reflexes. These structures may then act as a defense system, eliminating noxious stimulus substances sucked into the vomeronasal organ.
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  • 39
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    Anatomy and embryology 192 (1995), S. 329-334 
    ISSN: 1432-0568
    Keywords: First rib cartilage ; Immunohistochemistry ; Mineralization ; Ossification ; Collagen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The localization of fibrillar type I and II collagen was investigated by immunofluorescence staining with specific antibodies in order to obtain a better understanding of tissue remodelling during the development of first rib cartilage. In childhood and early adolescence type I collagen was found to be restricted to the perichondrium of first rib cartilage, while type II collagen was localized in the matrix of hyaline cartilage. However, in advanced age type I collagen was also found in the territorial matrix of intermediate and central chondrocytes of first rib cartilage. The matrix of subperichondrial chondrocytes was negative for type I collagen. This suggests that some chondrocytes in first rib cartilage undergo a modulation to type I collagen-producing cells. The first bone formation was observed in rib cartilages of 20- to 25-year-old adults. Interestingly, the ossification began peripherally, adjacent to the innermost layer of the perichondrium where areas of fibrocartilage had developed. The newly formed bone matrix showed strong immunostaining for type I collagen. Fibrocartilage bordering peripherally on bone matrix revealed only a faint staining for type I collagen, but strong immunoreactivity to type II collagen. The interterritorial matrix of the central chondrocytes failed to react with the type II collagen antibody, in both men and women, from the end of the second decade. These observations indicate that major matrix changes occur at the same time in male and female first rib cartilages. Thus, our findings indicate that ossification in human first rib cartilage does not follow the same pattern as that observed in endochondral ossification of epiphyseal discs or sternal cartilage.
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  • 40
    ISSN: 1432-0568
    Keywords: Connexin 32 ; Immunohistochemistry ; Enzyme histochemistry ; Renal tubule cell ; Hamster
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The expression of gap junction protein was examined immunohistochemically using affinity-purified antibody against rat liver gap junction protein, connexin 32 (Cx32), in the kidneys of fetal (gestation days 13–16) and adult Syrian golden hamsters. Phalloidin histochemical staining, PNA- and RCA I-lectin stainings, NCAM immunostaining, and alkaline phosphatase and Na+-K+-ATPase enzyme-histochemical staining were performed in combination with Cx32 immunostaining. The kidney sections were observed with a confocal scanning laser microscope. By gestation day 13, Cx32 immunoreactivity was observed in the differentiating tubules. The Cx32 staining was localized on the lateral cell membrane of the cells lining the developing proximal tubules, while the S-shaped bodies, developing distal tubules, and collecting tubules showed no positive immunostaining. As the kidney developed, the density of Cx32 immunoreactivity increased. As the gap junction provides pathways for cell-cell communication, the development of Cx32 expression may imply that this structure plays an important role in renal tubule development. Confocal scanning laser microscopy provided a clear image of the fluorescence-labeled cell structures, free from out-of-focus blur. Using the same sections, stereoscopic images were easily reconstructed from serial optical sections, and were helpful in understanding the spatial distribution of Cx32 expression in the developing fetal proximal tubules.
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  • 41
    ISSN: 1432-0568
    Keywords: Avian gut ; Differentiation ; Gut endocrine cells ; Regulatory peptides ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The ontogeny and the distribution of chromogranin A (CgA)- and chromogranin B (CgB)-immunoreactive endocrine cells was studied in the chicken gizzard and gizzard-duodenal junction (also called pylorus or antrum) during embryonic and postnatal life. The same tissue sections were then double-immunostained to identify the CgA- and CgB-immunoreactive cells, with a panel of polyclonal antibodies raised against main gut amine/peptides. In the gizzard, positive cells were observed only in its two diverticula (proximal and distal caeca), where the first CgA- and CgB-immunoreactive cells were found on day 12 of incubation. They always remained moderate in number and co-stored mainly serotonin, gastrin/CCK and neurotensin. A few also co-stored somatostatin, but only during the embryonic period. Others co-stored PYY, but only after hatching. Co-localization with motilin was rare and never occurred with bombesin. In the chicken antrum, the first CgA- and CgB-immunoreactive cells were observed on day 12 of incubation and soon reached very high numbers. Antral positive cells showed almost the same co-localization pattern as the gizzard diverticula. Despite their high chromogranin content, the antral cells had weak argyrophilia, whereas in the gizzard diverticula the two staining patterns corresponded.
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  • 42
    ISSN: 1432-0533
    Keywords: Alzheimer's disease ; Senile plaques ; Microglia ; Lysosomes ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract One of the major histopathological lesions in brains of patients with dementia of the Alzheimer type (DAT) is the senile plaque. Although previous studies have shown that senile plaques are often accompanied by microglial cells, the role of these cells in DAT pathology is still unclear. In an immunohistochemical and immuno-electron microscopical analysis of DAT and control brain tissues we addressed this issue using two monoclonal antibodies (mAbs KP1 and 25F9) directed against lysosomal antigens in monocytes and macrophages. Whereas KP1 stained lysosomes in both resting and activated microglial cells, 25F9-staining was predominantly found in lysosomes of activated microglial cells in classic senile plaques. The number and size of 25F9-positive lysosomes in activated microglial cells was increased compared to 25F9-staining in unaffected areas in DAT and control sections. We conclude that mAb 25F9 is a unique and useful lysosomal marker, with a higher specificity than other known markers, for activated microglial cells associated with classic, but not with diffuse, senile plaques.
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  • 43
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    Acta neuropathologica 90 (1995), S. 87-92 
    ISSN: 1432-0533
    Keywords: Key words Juvenile xanthogranuloma ; Intracerebral ; lesion ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Juvenile xanthogranuloma is usually a self-limiting disease of the skin. Intracranial manifestations are extremely rare. We report the clinico-pathological features of an 8-month-old boy suffering from a gradually enlarging nodule of the chest wall and subsequent epileptic seizures. The subcutaneous tumor and a cerebral subcortical tumor of the left temporal lobe were resected. The histological appearance of both tumors corresponded to juvenile xanthogranuloma and included histiocytes, foamy cells, giant cells, inflammatory cells, and collagen-producing fibroblasts showing a storiform pattern. Immunohistochemical studies demonstrated positivity of the tumor cells for lysozyme, CD68 and myeloid-histiocytic antigen, but not S-100 protein, supporting mono-histiocytic differentiation. This case indicates that juvenile xanthogranuloma should be considered in the differential diagnosis of intracranial "xanthomatous" and histiocytic lesions.
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  • 44
    ISSN: 1432-0533
    Keywords: Key words Human ; Amyotrophic lateral sclerosis ; Autoantibody ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Sera and cerebrospinal fluid (CSF) from 25 patients with amyotrophic lateral sclerosis (ALS) were tested by immunofluorescence on fetal, juvenile and adult central and peripheral neuronal (CNS/PNS) tissues and on nerve biopsy material from affected patients for the presence of autoantibodies. Results were compared with control sera from normal blood donors (n = 45) and patients with other neurological diseases (OND) (n = 11). Three different types of tissue reactivity (glial, axonal, and small blood vessels) were found. Antibodies binding to glial and axonal structures were found in 32% of ALS patients as compared to 12% in normal and 27% in OND controls. In contrast, staining of endothelial cells was found with 24% of ALS sera and CSF but not with normal and OND control sera and was demonstrated only with fetal and juvenile nervous tissue and with suralis nerve biopsies of two of five ALS patients. However, normal or inflamed adult CNS/PNS tissue was not stained with these sera. We conclude that ALS is most likely a heterogeneous group of diseases and only a subgroup of ALS may have an autoimmune pathogenesis. These findings may, therefore, have implications for the evaluation of any immunosuppressive treatment in ALS.
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  • 45
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    Anatomy and embryology 191 (1995), S. 561-568 
    ISSN: 1432-0568
    Keywords: Connexin 43 ; Immunohistochemistry ; Rat maxillary tooth germs
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Distribution of gap junction protein in maxillary tooth germs of 1-day-old rats was examined by immunohistochemistry, using an affinity-purified antibody specific to residues 360–376 of rat connexin (CX) 43. In 1-day-old rats, the maxillary second molar formed the shape of the cusp, but neither dentine nor enamel was formed between the cells of the dental papilla and the inner enamel epithelium. In the tooth germ, CX 43 was expressed in the cells of the stratum intermedium and the inner enamel epithelium. Labelling in the stratum inter-medium was extensive and showed an increasing gradient from peripheral to cuspal regions. CX 43 detected in the inner enamel epithelium was at cell surfaces facing the interface between the dental papilla and the inner enamel epithelium. The cells of the dental papilla and the inner enamel epithelium began differentiation as odontoblasts and secretory ameloblasts respectively, in the cusps of the first molars, where predentine and dentine were formed but enamel matrix was not secreted. CX 43 was present in the stratum intermedium, inner enamel epithelium, preodontoblasts, odontoblasts and subodontoblasts. The incisors showed the most advanced stage of development, where the enamel matrix and calcified dentine were formed in the labial part of the teeth. The CX 43 epitope was seen in the stratum intermedium, inner enamel epithelium, preameloblasts, preodontoblasts, odontoblasts, and subodontoblasts. Immunolabelling was more extensive in the stratum intermedium and subodontoblasts than in preameloblasts, preodontoblasts, and odontoblasts. The immunolabelling in preameloblasts and preodontoblasts was accumulated at cell surfaces facing the predentine. Further, the labelling in preameloblasts and preodontoblasts disappeared or was reduced at the initiation of enamel matrix secretion and calcification of dentine matrix. The present results suggest that gap junctional cell communication has important roles in tooth development. Further, the extensive CX 43 expression in the stratum intermedium and the subodontoblast layer suggests that gap junctions have an important role in amelogenesis and dentinogenesis.
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  • 46
    ISSN: 1432-0568
    Keywords: Glycogen ; Glycogen phosphorylase ; Histochemistry ; Immunohistochemistry ; Human embryo
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract To elucidate the role of glycogen in the epithelium of developing digestive organs, we investigated the appearance of glycogen and glycogen phosphorylase (GP) in these organs. We studied 64 externally normal human embryos at Carnegie stages 13–23 (5.1–28.0 mm in crown-ramp length, 4–8 weeks of gestation) by histocytochemical staining for glycogen and immunohistochemical staining with antibodies against two isoenzymes of GP: brain-type (BGP) and mucle-brain-type (MBGP) GP. At stage 13, glycogen appeared in the epithelium of the digestive tract and the parenchyma of the pancreas. As development advanced, glycogen granules increased in number and size in these tissues, and they became evenly distributed in the epithelium of the digestive tract as either single particles or aggregates, as deduced by electron microscopy at late embryonic stages. Immunoreactivity specific both for BGP and for MBGP was detected in the digestive tract and the pancreas from stage 13. As development advanced, both BGP- and MBGP-immunoreactive cells increased in number and in immunoreactivity, and the number of MBGP-immunoreactive cells became larger than that of BGP-immunoreactive cells. By contrast, in hepatic cells, which serve as a major storage site for glycogen in adults, glycogen was detected only from stage 20, in smaller amounts, without formation of aggregates, and no immunoreactivity specific for BGP or MBGP was apparent throughout the embryonic stages examined. Thus, in the epithelium of the digestive tract and the parenchyma of the pancreas, but not in hepatic cells, the appearance and localization of GP coincided almost exactly with that of glycogen. These observations suggest that glycogen in the epithelium of the digestive tract and the parenchyma of the pancreas has not only been synthesized but also degraded from an early embryonic period and may, thus, be related to active cellular metabolism that is specific for embryonic development, including proliferation of the epithelium and interactions between epithelium and mesenchyme.
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  • 47
    ISSN: 1432-0533
    Keywords: Key words Rabies ; Skunk ; Immunohistochemistry ; Viral transit in fiber tracts ; Pathogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Twenty-four striped skunks were inoculated intramuscularly (long digital extensor muscle of right pelvic limb) with street rabies virus. Groups of two clinically normal skunks were killed at various times after inoculation; skunks that developed rabies were killed in early stages of the clinical signs. Four clinically normal skunks (numbered 1–4) had slight infection in lumbar spinal ganglia, spinal cord and brain. These four skunks were used for detailed immunohistochemical (rabies antigen) studies that included examination of sections from every segment of the spinal cord, most of the spinal ganglia from the 2nd cervical to the 2nd coccygeal (sections at 25-μm intervals of lumbar, sacral and coccygeal ganglia) and brain (sections at 50-μm intervals). In skunks 1–4, there was increasing distribution of antigen-containing neurons that was not correlated with the time elapsed since inoculation. In three skunks (nos. 1, 2 and 3), antigen-containing neurons were predominantly in caudal regions of the spinal cord, caudal right lumbar and sacral spinal ganglia and certain nuclei/regions of the brain (medial reticular formation, right interpositus and lateral vestibular nuclei, left red nucleus, left motor cortex, and left reticular nucleus of the thalamus). Skunk 4 had more extensive infection than skunks 1–3, but the previous pattern was still evident. The results are consistent with viral entrance into the lumbar spinal cord, initial replication mainly at the L2 and L3 levels, local spread in the cord by propriospinal neurons and early transit to the brain via long ascending and descending fiber tracts (bypassing the grey matter of the rostral spinal cord). These mechanisms could provide for early and rapid dissemination in the brain before a significant immune response develops and could induce behavioral changes before the animal is incapacitated by extensive spinal cord infection. Based on the distribution of antigen-containing neurons, the tracts considered most likely to serve as viral transitways from spinal cord to brain include: rubrospinal, corticospinal, spinothalamic, spino-olivary, vestibulospinal and/or spinovestibular, reticulospinal and/or spinoreticular, cerebellospinal and/or spinocerebellar, and dorsal column pathways.
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  • 48
    ISSN: 1432-0533
    Keywords: Adult T cell leukemia ; HTLV-I ; Immunohistochemistry ; In situ polymerase chain reaction ; p53 protein
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We report the pathological changes in skeletal muscle from a patient with acute adult T cell leukemia (ATL). HTLV-I provirus was detected in infiltrating cells using in situ polymerase chain reaction in frozen sections. Furthermore, aberrant expression of the p53 protein was observed in the infiltrating cells. As p53 protein was not observed in mononuclear inflammatory cells in patients with polymyositis, expression of the p53 protein was considered to be one of the characteristic findings in ATL cells. This is the first direct detection of ATL cells in skeletal muscle.
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  • 49
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    Anatomy and embryology 192 (1995), S. 117-121 
    ISSN: 1432-0568
    Keywords: Horse atrium ; Cardiodilatin/atrial natriuretic peptide ; Brain natriuretic peptide ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The distribution of immunoreactivity (IR) for cardiodilatin/atrial natriuretic peptide (CDD/ANP) and brain natriuretic peptide (BNP) was examined immunohistochemically and immuno-electron-microscopically in the equine atrium, using specific antibodies. In the immunohistochemical studies, IR-CDD/ANP and IR-pBNP-26 (porcine BNP-26 immunoreactivity) was detected in the cytoplasm of the auricular cardiocytes, but IR-hBNP-32 (human BNP-32 immunoreactivity) was not. The double immunogold labelling method for IR-hBNP-28 and IR-pBNP-26 revealed that gold particles of different sizes were located in the same secretory granules in the cardiocyte, but no gold particles for IR-hBNP-32 were detected. These results show that CDD/ANP and porcine BNP-like peptides are colocalized in the same secretory granules of the equine atrium. They suggest that the equine atrium secretes both CDD/ANP and BNP-like peptides.
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  • 50
    ISSN: 1432-0533
    Keywords: Chordoma ; Ploidy ; Silver nucleolar organizing region ; Pathology ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Chordomas are slow growing malignant neoplasms with a prolonged clincial course which do not usually metastasize. They are histologically benign, locally invasive and often recur following resection. Survival has been shown to vary widely and prognostic indicators have been difficult to identify. Cellularity, mitotic activity and cellular pleomorphism have not been found to have prognostic significance. Thirty-six cases of clival, cervico-thoracic and sacral chordomas were evaluated utilizing four variables as possible predictors of survival: (1) silver nucleolar organizing region (AgNOR), (2) ploidy, (3) fibrosis, and (4) inflammatory response. AgNOR areas in approximately 200 cells per case were calculated and summed. DNA ploidy was obtained in 23 of the cases by analyzing deparaffinized Feulgen-stained tissue. Fibrosis and inflammation were evaluated by hematoxylin and eosin and by trichrome stains. Clinical follow-up was available in the 36 cases with survival ranging from 0.5 to 159 months. A statistical analysis employing the Cox-Proportional Hazards model disclosed no significant correlation between AgNOR area and clinical outcome (P〉0.05). The variables, fibrosis, and inflammation, did not demonstrate prognostic significance (P〉0.05). Ploidy demonstrated a statistical trend for prognostic significance (P=0.077). It is apparent that three of the four parameters studied do not independently affect survival. Although AgNOR has proved useful in the study of other neoplasms such as those of breast, prostate and bladder, it is not of significant importance in predicting the behaviour of chordomas. Ploidy, on the other hand, may be of value in predicting clinical outcome in chordomas and may be a useful marker in the evaluation of the aggressive biological behavior of these neoplasms.
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  • 51
    ISSN: 1432-0533
    Keywords: Key words Chordoma ; Ploidy ; Silver nucleolar ; organizing region ; Pathology ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Chordomas are slow growing malignant neoplasms with a prolonged clinical course which do not usually metastasize. They are histologically benign, locally invasive and often recur following resection. Survival has been shown to vary widely and prognostic indicators have been difficult to identify. Cellularity, mitotic activity and cellular pleomorphism have not been found to have prognostic significance. Thirty-six cases of clival, cervico-thoracic and sacral chordomas were evaluated utilizing four variables as possible predictors of survival: (1) silver nucleolar organizing region (AgNOR), (2) ploidy, (3) fibrosis , and (4) inflammatory response. AgNOR areas in approximately 200 cells per case were calculated and summed. DNA ploidy was obtained in 23 of the cases by analyzing deparaffinized Feulgen-stained tissue. Fibrosis and inflammation were evaluated by hematoxylin and eosin and by trichrome stains. Clinical follow-up was available in the 36 cases with survival ranging from 0.5 to 159 months. A statistical analysis employing the Cox-Proportional Hazards model disclosed no significant correlation between AgNOR area and clinical outcome (P 〉 0.05). The variables, fibrosis, and inflammation, did not demonstrate prognostic significance (P 〉 0.05). Ploidy demonstrated a statistical trend for prognostic significance (P = 0.077). It is apparent that three of the four parameters studied do not independently affect survival. Although AgNOR has proved useful in the study of other neoplasms such as those of breast, prostate and bladder, it is not of significant importance in predicting the behaviour of chordomas. Ploidy, on the other hand, may be of value in predicting clinical outcome in chordomas and may be a useful marker in the evaluation of the aggressive biological behavior of these neoplasms.
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  • 52
    ISSN: 1432-0533
    Keywords: Pick body ; Lewy body ; Locus ceruleus ; Pick's disease ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We observed abundant Pick argentophilic inclusion bodies (PBs) as well as some atypical Lewy bodies (LBs) in the locus ceruleus (LC) from a patient with Pick's disease. In addition, there were a few neurons which contained both PBs and LBs. PBs in the LC frequently appeared multiple and had lobulated or irregular shapes, though their ultrastructural elements were the same as those of the PBs appearing in the cerebral cortex, and consisted of randomly arranged smooth-surfaced straight tubules of 15 nm in diameter, mixed with a small number of long-period constricted fibrils. The ultrastructure of the LB coexisting with PB was identical with that previously reported; a dense core was surrounded by concentric layers of radially oriented 10-nm filaments and was clearly distinguishable from the PB. Immunohistochemical examination with various antibodies related to neurofibrillar pathology demonstrated that anti-tau antibodies reacted positively with both PB and the rim portion of LB in the present case; an unusual finding for LB. The anti-neurofilament 200-kDa protein stained only LBs, even when PBs and LBs coexisted in the same neuron. These findings show that two kinds of neuronal fibrillar inclusions, whose underlying cytoskeletal abnormalities are thought to be different, can coexist in the same neuron. In addition, the formation of multiple, lobulated PBs may suggest some particularity of cytoskeletal composition of the LC neurons.
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  • 53
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    Acta neuropathologica 90 (1995), S. 87-92 
    ISSN: 1432-0533
    Keywords: Juvenile xanthogranuloma ; Intracerebral lesion ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Juvenile xanthogranuloma is usually a self-limiting disease of the skin. Intracranial manifestations are extremely rare. We report the clinico-pathological features of an 8-month-old boy suffering from a gradually enlarging nodule of the chest wall and subsequent epileptic seizures. The subcutaneous tumor and a cerebral subcortical tumor of the left temporal lobe were resected. The histological appearance of both tumors corresponded to juvenile xanthogranuloma and included histiocytes, foamy cells, giant cells, inflammatory cells, and collagen-producing fibroblasts showing a storiform pattern. Immunohistochemical studies demonstrated positivity of the tumor cells for lysozyme, CD68 and myeloid-histiocytic antigen, but not S-100 protein, supporting mono-histiocytic differentiation. This case indicates that juvenile xanthogranuloma should be considered in the differential diagnosis of intracranial “xanthomatous” and histiocytic lesions.
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  • 54
    ISSN: 1432-0533
    Keywords: Alzheimer's disease ; Neurofibrillary tangles ; Amyloid ; Ultrastructure ; Immunohistochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Senile plaque and paired helical filament (PHF) formation are characteristic of Alzheimer's disease, but the mechanisms leading to these lesions still remain unclear. To understand them better, we have performed different immunolabellings of amyloid protein and PHF. We describe a very specific immunodetection of PHF with AD2, a monoclonal antibody directed against a hyperphosphorylated epitope of PHF-tau, and use double immunolabelling to show that PHF and plaque amyloid are discretely labbeled by different antibodies. We also discuss different mechanisms of PHF maturation.
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  • 55
    ISSN: 1432-0533
    Keywords: Key words Adult T cell leukemia ; HTLV-I ; Immunohistochemistry ; In situ polymerase chain reaction ; p53 protein
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We report the pathological changes in skeletal muscle from a patient with acute adult T cell leukemia (ATL). HTLV-I provirus was detected in infiltrating cells using in situ polymerase chain reaction in frozen sections. Furthermore, aberrant expression of the p53 protein was observed in the infiltrating cells. As p53 protein was not observed in mononuclear inflammatory cells in patients with polymyositis, expression of the p53 protein was considered to be one of the characteristic findings in ATL cells. This is the first direct detection of ATL cells in skeletal muscle.
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  • 56
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    Anatomy and embryology 191 (1995), S. 191-201 
    ISSN: 1432-0568
    Keywords: Striatum ; Cell adhesion ; Development ; Immunohistochemistry ; KG-CAM
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The present study examines the developmentally regulated expression pattern of an Ig superfamily member, KG-CAM, in the neostriatum of the rat. KG-CAM is a 90-kDa glycoprotein that is related to the DM-GRASP/Neurolin family of adhesion molecules. In the embryonic and early postnatal neostriatum, the distribution of KG-CAM correlates with the distribution of dopaminergic terminals. Early in neostriatal development, KG-CAM is found in the tyrosine hydroxylase-positive patches. In the maturing neostriatum, the levels of KG-CAM remain high within the patches, and KG-CAM upregulates in the matrix compartment. As the neostriatum is reaching its adult morphology, 5 weeks postnatal, the expression of KG-CAM in the matrix is approximately equal to that of the patches. When the distribution of KG-CAM is examined at the ultrastructural level, the immunoreactivity is localized to the external surface of neuronal and glial profiles in the neuropil. KG-CAM does not appear to be associated with the guidance of dopaminergic axons from the substantia nigra to the striatum, for this pathway is not immunopositive for this member of the Ig superfamily. The present study identifies an Ig superfamily member, KG-CAM, that appears to play a major role in the development of the neostriatum. Furthermore, the high levels of KG-CAM in the adult neostriatum suggest that this Ig superfamily member may be involved in maintaining the integrity of this structure in the adult rat.
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  • 57
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1285-1293 
    ISSN: 0392-6737
    Keywords: Localized single-particle electronic states (excluding impurities) ; Electron states in low-dimensional structures (including quantum wells, superlattices, layer structures, and intercalation compounds) ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary We discuss some specific properties of self-organized InAs-GaAs quantum dots grown by Molecular Beam Epitaxy. We report on the optical spectra obtained under resonant excitation, where both a Raman contribution and a resonant emission of the dots are evidenced. We show that the emission of single dots can easily be isolated by processing measas on samples with a graded indium content, and finally discuss the temporal and temperature behaviour of the emission.
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  • 58
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1315-1322 
    ISSN: 0392-6737
    Keywords: Excitons and related phenomena (including electron-hole drops) ; Time resolved optical spectroscopies and other ultrafast optical measurements in condensed matter ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary The concept of coherence due to optical excitation of an ensemble of two-level atoms is relatively simple and well established. For the laser-excited electron-hole pairs or excitions in a semiconductor, the Pauli exclusion and the Coulomb interaction lead to the necessary evolution of the theory of coherence to incorporate the spin degree of freedom, the filling of phase space, the excitons and particularly, their correlation. We have developed two theoretical approaches: one using the Feynman diagrams and one in terms of a force-force correlation function. The former gives us a pictorial way to describe the optical processes and the latter gives us a prescription for computation beyond the perturbative approach. In this paper, we will attempt to use simple physical pictures based on our theory to describe the time development of the coherence, the role of correlation, the dependence on the polarization of light, and the nonlinear time-resolved optical experiments which measure the coherence.
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  • 59
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1401-1405 
    ISSN: 0392-6737
    Keywords: Electromagnetic wave propagation ; radiowave propagation ; Developments in band-structure calculation techniques ; Other topics in optical properties of condensed matter and other interactions of matter with particles and radiations ; Other topics in electromagnetic technology ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary Recently, periodic dielectric structures have been proposed to inhibit spontaneous emission in semiconductors. From this suggestion, the new concepts of photonic band gap and photonic crystal have been developed. Zero-threshold lasers, wave guides and polarizers are promising applications. A new class of twodimensional periodic structures with hexagonal symmetry is investigated in order to obtain photonic band gap materials. This set has the hexagonal symmetry and contains, in particular, several structures previously discussed. The photonic band gap structure is related to the basic properties of the materials and some features of the opening of the gaps are explained. By varying the crystal pattern, we show how band gaps common toE andH polarizations appear for a new design of two-dimensional periodic dielectric structures. The dependence of the widths of these gaps on the filling patterns is studied and potential application for the creation of photonic crystals in the optical domain is discussed.
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  • 60
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1429-1433 
    ISSN: 0392-6737
    Keywords: Excitons and related phenomena (including electron-hole drops) ; Localised single-particle electronic states (excluding impurities) ; Photoluminescence ; II–VI semiconductors ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary Time-resolved photoluminescence experiments in a wide carrier density range up to and beyond the threshold for stimulated emission in ZnSe/ZnS x Se1−x superlattices are presented. Different localisation mechanisms of free excitons are identified giving rise to different radiative recombination channels. At high carrier density localised energy states merge into miniband that allows for exciton-exciton interaction, such as screening of the free-exciton absorption and inelastic exciton-exciton scattering.
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  • 61
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1407-1412 
    ISSN: 0392-6737
    Keywords: Excitons and related phenomena (including electron-hole drops) ; Surface and interface electron states ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary We have investigated the fine structure of luminecence of CdSe nanocrystals observed with size-selective excitation. We show that the luminescence line closest to the laser arises from the recombination of the optically forbidden A-exciton. Radiative recombination occurs via a phonon-assisted virtual transition to theB-exciton state. The electron-hole exchange energy obtained from the experimental results strongly increases with decreasing nanocrystal size as expected from the increasing overlap of the electron and hole wave functions. The size dependence is in good agreement with the theoretical predictions.
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  • 62
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1423-1427 
    ISSN: 0392-6737
    Keywords: Excitons and related phenomena (including electron-hole drops) ; Surface and interface electron states ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary Normalized reflection spectra in GaInAs/GaAs quantum wells are shown for two sets of samples with different alloy concentration (x=9% and 18.5%) and well thickness ranging from 1.5 nm to 25 nm. All samples were grown on (001) GaAs surface by Molecular Beam Epitaxy and characterized by RHEED and X-ray reflection diffraction. Exciton envelope function in effective mass approximation and optical response in polaritonic schema are computed. Normalized reflection spectroscopy has shown itself to be a well suited technique in order to study structural and electronic properties of confined quantum structures.
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  • 63
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1447-1452 
    ISSN: 0392-6737
    Keywords: Excitons and related phenomena (including electron-hole drops) ; Optical properties of thin films, surfaces, and layer structures (superlattices, heterojunctions, and multilayers) ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary We investigate the absorption spectrum and the distribution of radiative decay times for two-dimensional excitons in semiconductor quantum wells, as affected by an adiabatic white-noise random potential. Such a potential could result from atomic-scale fluctuations in the composition of an alloy semiconductor, or in quantum well thickness. We find in general that the shortest radiative decay time is directly proportional to the inhomogeneous width of the exciton line in absorption, itself proportional to the correlation parameter for the random potential.
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  • 64
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1473-1479 
    ISSN: 0392-6737
    Keywords: Surface and interface electron states ; Excitons and related phenomena (including electron-hole drops) ; Polaritons (including photon-phonon and photon-magnon interactions) ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary We report the evidence of exciton-polariton centre-of-mass quantization in II–VI quantum wells consisting of ternary alloy. Absorption and photoluminescence studies on Zn0.89Cd0.11Se/ZnSe quantum wells, covering the intermediate region between two- and three-dimensional exciton behaviour, exhibit distinct optical resonances in the high-energy tail of the free-exciton structure. We reproduce the well width dependence of the centre-of-mass states by modeling the optical response of the QWs with a thin-slab variational wave function, which takes into account non-adiabatic terms.
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  • 65
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1499-1503 
    ISSN: 0392-6737
    Keywords: Optical properties of thin films, surfaces, and thin layer structures (including superlattices, heterostructures, and intercalation compounds) ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary We have studied modulation spectra related to the intersubband transitions at 300 K and 20 K from an In GaAs/GaAs-strained asymmetric triangular quantum well (ATQW) heterostructures fabricated by molecular beam epitaxy using the digital alloy compositional grading (DACG) method. A careful analysis of the spectra has led to the identification of various excitonic transitions,mnh(1), between them-th conduction band state to then-th, heavy (light)-hole band state. Comparison of the observed intersubband transitions with a theoretical calculation based on the envelope, function model, including the effects of strain provided a self-consistent verification that the DACG method produced the intended ATQW composition profile.
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  • 66
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1519-1526 
    ISSN: 0392-6737
    Keywords: Electron states in low-dimensional structures (including quantum wells, superlattices, layer structures, and intercalation compounds) ; III–V compounds and systems ; III–V semiconductors ; Polarimeters and ellipsometers ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary Luminescence investigations on MBE-grown AlAs/AlGaAs microcavities reveal position-dependent spectra from embedded GaAs quantum wells and from the reflector material. Because of their uniform energetic shifts they should be connected with the spatial distribution of strain. The spectra themselves are related to the radiative recombination of confinement-shifted free-electron-hole pairs, free and bound excitons and to the intrinsic luminescence of AlGaAs. Ellipsometric investigations in the range of the resonator stop band around 1.5 eV accentuate the one-dimensional behaviour as a 1D singularity within the effective joint density of states. The resonator mode and the stop band are dependent on the angle of incidence. The effective dielectric function is metal-like with the maximum imaginary part above 103,i.e. as it is typical for a pure metal in the FIR. Analogous investigations between 2.5 and 3.5 eV determined the critical pointsE 0 andE 1 of the energy band structure of AlAs and AlGaAs, respectively.
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  • 67
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    Keywords: Studies of specific magnetic materials ; Optical properties of thin films surfaces and layer structures (superlattices, heterojunctions and multilayers) ; Excitons and related phenomena (including electron-hole drops) ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary Two qualitatively different e-h systems have been investigated in undoped CdTe/Cd0.88Mn0.12Te and Cd0.97Mn0.03 Te/Cd0.75Mn0.25 Te QWs at 2 K and magnetic fields up to 14 T, namely a strongly spin-depolarized system in the CdTe QW and a highly spin-polarized one in the Cd0.97Mn0.03 Te QW. The interaction of the spin-aligned excitons is repulsive. In contrast, in the spectra of a dense spin-depolarized excitonic system an additional well pronounced emission lineM was observed at approximately 5 meV below the excitonic line. This line is assigned to the emission of molecules consisting of excitons with opposite spins of both electrons and holes.
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  • 68
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1573-1578 
    ISSN: 0392-6737
    Keywords: Time-resolved optical spectroscopies and other ultrafast optical measurements in condensed matter ; Excitons and related phenomena (including electron-hole drops) ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary We report on the observation of an electric-field-induced electric-dipole moment of biexcitonic molecules in a GaAs/Al0.3Ga0.7As superlattice. The macroscopic oscillating electric field, associated with the microscopic wave packet dipole moments, is monitored by time-resolved transmittive electro-optic sampling. The field dependence of the biexcitonic binding energy is detected by transient four-wave mixing. From these experiments, an ultrafast non-resonant excitation mechanism of biexcitons is inferred.
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  • 69
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    Keywords: Time-resolved optical spectroscopies and other ultrafast optical measurements in condensed matter ; Photoluminescence ; II–VI compounds and other chalcogenides ; Conference proceedings
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    Topics: Physics
    Notes: Summary Resonant photoluminescence and excitation spectroscopy and time-resolved photoluminescence are performed on a 50 Å thick ZnSe/(Zn, Mn) Se strained quantum well. From these experiments, the existence of a relaxation from a type-II heavy-hole bound interface exciton to a type-I light-hole exciton is demonstrated. The time transfer from the heavy-hole exciton to the light-hole exciton is found to be of the same order of magnitude as the recombination time of the heavy-hole exciton. This transfer is enhanced when temperature increases.
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  • 70
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1255-1264 
    ISSN: 0392-6737
    Keywords: Excitons and related phenomena (including electron-hole drops) ; Polaritons (including photon-photon and photon-magnon interactions) ; Conference proceedings
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    Topics: Physics
    Notes: Summary We develop the bipolariton concept for a quasi-2D excitonic molecule (m) in quantum wells (QWLs). The bipolariton wave equation, which includes both the exciton-exciton (x-x) attraction and thex-photon (γ) coupling, is analysed. In the 2D bipolariton model, a quasi-2Dm exists in QWLs mainly as two quasi-boundsurface polaritons and, consequently, decays mainly into two outgoing surface polaritons. In quasi-2D GaAs QWLs the polariton renormalizations give rise to a «Mexican hat» structure in them dispersion at small momenta together with a considerable increase of both them effective binding energy ɛ m and the inversem radiative lifetimeГ m . A van Hove singularity in the joint density of polariton states is responsible for this effect.
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  • 71
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1657-1662 
    ISSN: 0392-6737
    Keywords: Excitons and related phenomena (including electron-hole drops) ; Polaritons (including photon-phonon and photon-magnon interactions) ; Dynamics of nonlinear optical systems ; optical instabilities, optical chaos, and optical spatio-temporal dynamics ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary The linewidth of the microcavity exciton polariton is studied by onresonant and off-resonant photoluminescences. The two main contributions to the linewidth are caused by radiative loss and phonon scattering. The oscillator strength is found to be unmodified by the exciton-phonon coupling. Comparison is made between theory and experiment.
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  • 72
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1693-1697 
    ISSN: 0392-6737
    Keywords: High-field and nonlinear effects ; Theory of electronic transport ; scattering mechanism ; Ultrafast optical techniques ; Optical properties of thin films, surfaces and layer structures (superlattices, heterojunctions, and multilayers) ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary The effective dimensionality of excitons can be drastically changed by applying an alternating electric field. On the basis of a full three-dimensional description of both coherent and incoherent phenomena in anisotropic structures it is found that appropriate applied oscillating fields change the exciton wave function from anisotropic three dimensional to basically two dimensional. This effective-dimension change is caused by dynamic localization which leads to an increase of the exciton binding energy and of the corresponding oscillator strength.
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  • 73
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1717-1722 
    ISSN: 0392-6737
    Keywords: Excitons and related phenomena (including electron-hole drops) ; Time-resolved optical spectroscopies and other ultrafast optical measurements in condensed matter ; Conference proceedings
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    Topics: Physics
    Notes: Summary The coupled dynamics of free carriers and excitons after non-resonant excitation with short laser pulses is investigated by means of an Ensemble Monte Carlo method which includes phonon-assisted formation and dissociation of free excitons. Simulations for bulk GaAs reveal that excitonic binding under participation of LO phonons is a very fast and effective process. The temporal rise of exciton luminescence depends on the particular excitation conditions and is determined by all interaction mechanisms in the system.
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  • 74
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1743-1746 
    ISSN: 0392-6737
    Keywords: Wave propagation transmission and absorption ; Optical properties of thin films, surfaces, and layer structures (superlattices, heterojunctions, and multilayers) ; Polaritons (including photon-phonon and photon-magnon interactions) ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary An analysis of the optical properties of an array of quantum wires of cylindrical shape is presented. Effects of the electromagnetic coupling between the wires are found to be given by additional energy shifts and modified oscillator strengths of the reflectivity peaks with respect to the single-wire exciton polariton ones previously calculated. Numerical values for realistic structures show the importance of these effects. Changes of the lifetimes of the single-wire excitations produced by this electromagnetic coupling are also put into evidence. In particular, the short lifetimes of the two-dimensional exciton-polariton are recovered when the interwire distanceD is smaller than the wavelength λ of light. Stationary, or non-radiative electromagnetic modes are also expected in this close-packed case. These radiative and non-radiative modes therefore show some analogies with those found in two-dimensional systems such as quantum wells.
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  • 75
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1747-1751 
    ISSN: 0392-6737
    Keywords: Polaritons (including photon-phonon and photon-magnon interactions) ; Excitons and related phenomena (including electron-hole drops) ; Quantum optics ; Electron states in low-dimensional structures (including quantum wells, superlattices, layer structures, and intercalation compounds) ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary A great interest in the study of exciton-photon coupling in resonant optical media such as semiconductor microcavities is currently developing both in experiments and in theory. We investigate the spectral response of a new semiconductor quantum system in which the cavity material itself is the active medium. If the Fabry-Perot quasi-mode is carefully tuned on the excitonic transition of the cavity bulk material, strong exciton-photon coupling takes place and produces new features such as a Rabi-like splitting as large as that observed in quantum well microcavities and comparable optical absorption. In addition, the polaritonic spatial dispersion and the quantization of the centre-of-mass motion introduce remarkable fine structures which are absent in the quantum well case. We demonstrate the above effects from a spectroscopic analysis of GaAs cavities, using standard reflectance and photoluminescence techniques. The experimental results are further clarified with theoretical calculations performed with an adapted transfer-matrix approach. The case of semi-cavities is finally considered and a new way to control the exciton-photon interaction in our system is achieved tailoring the photonic wave function with a change in the reflectivity phase of the mirrors.
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  • 76
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1775-1779 
    ISSN: 0392-6737
    Keywords: Electron states in low-dimensional structures (including quantum wells, superlattices, layer structures, and intercalation compounds) ; Dielectric, piezoelectric, and ferroelectric materials ; Electrooptical effects ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary We describe an experimental and theoretical investigation of Wannier-Stark ladders in the optical spectra of (111)B InGaAs/GaAs piezoelectric superlattices. A unique feature of these structures is that an external electric field can be used to produce a flat superlattice—that is zero overall potential drop per period—in which there are large, opposing fields in the well and barrier. These fields cause a spatial separation of the electron and hole wave functions in the axial direction, leading to Stark ladderss which are intermediate between Type I (electrons and holes together) and Type II (electrons and holes separated by half a period) in character.
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1801-1805 
    ISSN: 0392-6737
    Keywords: Excitons and related phenomena (including electron-hole drops) ; Time-resolved optical spectroscopies and other ultrafast optical measurements in condensed matter ; Electron states in low-dimensional structures (including quantum wells ; superlattices ; layer structures ; and intercalation compounds ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary Disorder-induced Rayleigh scattering of excitons in quantum wells is investigated theoretically. For classical excitions (long-range spatial correlation), the disorder average can be performed exactly. For the full problem, a kinetic equation with «weak memory» for the excition distribution is derived which coincides with the classical result in the appropriate limit. The theoretical results are compared with recent experimental data on femtosecond time-resolved luminescence explaining well the finite rise time and the heavy-light-hole beating.
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  • 78
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 733-741 
    ISSN: 0392-6737
    Keywords: General, theoretical, and mathematical biophysics (including logic of biosystems, quantum biology, and relevant aspects of thermodynamics, information theory, cybernetics, and bionics) ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary Recent experiments show that the neural codes at work in a wide range of creatures share some common features. At first sight, these observations seem unrelated. However, we show that all of these features of the code arise naturally in a simple threshold crossing model when we choose the threshold to maximize the transmitted information. This maximization process requires neural adaptation to not only the d.c. signal level, as in conventional light and dark adaptation (for example), but also to the statistical structure of the signal and noise distributions. Interestingly, if we fix the threshold level, we can observe a peak in the transmitted information at a finite value of the input signal-to-noise ratio. However, when we allow the threshold to adapt to the statistical structure of the signal and noise, the transmitted information is always monotonically increasing with increasing input signal-to-noise ratio.
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  • 79
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    Keywords: Optical bistability, multistability, and switching ; optical computers ; Fluctuation phenomena, random processes and Brownian motion ; Optical resonantors ; Probability theory, stochastic processes and statistics ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary Statistical distributions, power spectra and susceptibilities of an all-optical bistable system subject to noise are considered. In the presence of an additional small periodic signal, a stochastic-resonance phenomenon for additive noise is found to occur, and has been investigated theoretically and experimentally. A new form of optical heterodyning related to stochastic resonance, in which two high-frequency signals (an input signal and a reference one) are applied to an all-optical bistable system, is reported. A noise-induced enhancement of the heterodyne signal has been investigated theoretically, by means of analogue electronic simulation and in experiments in which a optical system was driven by two modulated laser beams at different wavelengths.
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 725-731 
    ISSN: 0392-6737
    Keywords: General, theoretical, and mathematical biophysics (including logic of biosystems, quantum biology, and relevant aspects of thermodynamics, information theory, cybernetics, and bionics) ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary The effect of a weak periodic perturbation on the firing activity of two different types of neurons is investigated. Post-stimulus and interspike interval histograms are built up from the times of occurrence of the action potentials and a comparative analysis is performed between the two preparations. A discussion of how the leaky integrate-and-fire model can mimic the experimental data is included.
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 653-660 
    ISSN: 0392-6737
    Keywords: Chaos ; Theory and models of chaotic systems ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary We discuss the complexity in dynamical systems with a random perturbation by considering the rateK of divergence of nearby orbits evolving under two different noise realization. This quantity has a clear meaning in the context of the information theory and it has physical relevance for the analysis of experimental data. Our definition of complexity becomes crucial for strongly intermittent systems whereK is very different from the Lyapunov exponent.
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 685-697 
    ISSN: 0392-6737
    Keywords: Active transport processes ; Fluctuation phenomena, random processes, and Brownian motion ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary Ratchets are anisotropic periodic potentials. Particles subject to ratchet forces and simultaneously to thermal and nonthermal fluctuations can rectify the nonequilibrium noise, thereby extracting energy from incoherent and otherwise symmetric random forces. In this paper I describe some simple models which illustrate this phenomenon, highlighting two particular mechanisms leading to fluctuation-induced current.
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 709-723 
    ISSN: 0392-6737
    Keywords: Nonlinear theories (including bifurcation theory) ; Fluctuation phenomena, random processes, and Brownian motion ; Theory and models of chaotic systems ; Computational modeling: simulation ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary The statistical properties of non-linear dynamical systems are studied using the master equation approach. Detailed analysis of a model system undergoing a Hopf bifurcation reveals a non-trivial interference between macroscopic behaviour and microscopic dynamics in spatially extended systems. The effect of intrinsic fluctuations in the regime of homogeneous deterministic chaos is also analysed and the robustness of the macroscopic description is confirmed.
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 855-861 
    ISSN: 0392-6737
    Keywords: Chaos ; Theory and models of chaotic systems ; Instability and shear flows ; Conference proceedings
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    Topics: Physics
    Notes: Summary Analysis is presented of a system, derived previously as a low-order model for the shear instability of convection, whose dynamics are dramatically simplified by tiny amounts of additive noise. The dynamics divide naturally into two phases. In the slower phase, trajectories are close to an invariant manifold; this allows small random disturbances to exert a controlling influence. A map is derived which provides an accurate description of the trajectories.
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 883-891 
    ISSN: 0392-6737
    Keywords: General, theoretical, and mathematical biophysics (including logic of biosystems, quantum biology, and relevant aspects of thermodynamics, information theory, cybernetics, and bionics) ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
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    Notes: Summary The contribution of chemical steps in trasduction chains to the output noise of a receptor cell (as opposed to the noise inherent in the stimulus,e.g., a dim light flash) has been evaluated both analytically and by a computer simulation study on a simple model, using a Monte Carlo technique. The noise deriving from chemical reactions (chemical shot noise, CSN) is shown to add to the source noise thereby increasing significantly the output variation coefficient. It is proposed that this noise contribution should be taken into account in interpreting the sensitivity of a sensory system and in particular the dose-response curves at low levels of the stimulus.
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 941-947 
    ISSN: 0392-6737
    Keywords: Physiological optics: vision ; General, theoretical, and mathematical biophysics (including logic of biosystems, quantum biology, and relevant aspects of thermodynamics, information theory, cybernetics, and bionics) ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary Both bottom-up sensory information and top-down influences contribute to the perception processes. We studied the perceptual alternations of a multistable ambiguous pattern. We observed that it is possible to interfere on the process of the perception alternance by means of subliminal visual stimuli, which either contrast or second the previous perception. We investigated also the effect of the top-down volitional factor on the perceptual alternation. By using a combination of such top-down factor and bottom-up stimulation, we ascertained that a non-linear type of interaction occurs between the two above factors.
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1265-1276 
    ISSN: 0392-6737
    Keywords: Polaritons (including photon-phonon and photon-magnon interactions) ; Optical properties of thin films, surfaces, and layer structures (superlattices, heterojunctions, and multilayers) ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary The transport of radiative and electronic excitations in coherently driven semiconductor quantum wells is analysed. On ultrashort time scales the spatial dynamics is determined by light propagation only, whereas for longer times the propagation of light and electronic excitations may be coupled. The theory is applied to the propagation of electronic excitations in the plane of a single quantum well and to polariton propagation in quantum well wave guides.
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1323-1332 
    ISSN: 0392-6737
    Keywords: Excitons and related phenomena (including electron-hole drops) ; Polaritons (including photon-phonon and photon-magnon interactions) ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary We present an extensive set of absorption and PL measurements on semiconductor microcavities in the strong-coupling regime. We observe strong coupling from 110 K to room temperature. We look at the behaviour of the photoluminescence for different exciton-photon detuning. We discuss this data using two different pictures, the first is a non-interacting (uncoupled) picture of an exciton in a cavity filter. The second model is that of a cavity polariton and this explains the observed dynamics in the strong-coupling regime. We show how the opposing needs of strong coupling and high photoluminescence extraction efficiency can be reconciled.
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1343-1347 
    ISSN: 0392-6737
    Keywords: Excitons and related phenomena (including electron-hole drops) ; Polarons and electron-phonon interactions ; Electron states in low-dimensional structures (including quantum wells, superlattices, layer structures, and intercalation compounds) ; III-V compounds and systems ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary We have calculated the binding energies of excitons in quantum well structures based on ionic semiconductors by including the electron-hole interactions with the longitudinal-optical-phonon field. We have taken into account these interactions by using different effective interaction potentials between the electron and the hole as derived by Haken, Aldrich and Bajaj, and Pollman and Buttner. We have calculated the binding energies of excitons in several ionic quantum well structures as functions of well width using these effective potentials following a variational approach. We find that the values of the exciton binding energies calculated using these potentials are always larger than those, obtained using a Coloumb potential screened by static dielectric constant.
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1355-1358 
    ISSN: 0392-6737
    Keywords: Time-resolved optical phenomena (including electron-hole drops) ; Optical properties of thin films surfaces, and layer structures (superlattices, heterojunctions and multilayers) ; Electron states in low-dimensional structures (including quantum wells, superlattices, layer structures, and intercalation compounds) ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary We show that a detailed understanding of the influence of the exciton-exciton interaction on the non-linear excitonic response in a GaAs/AlGaAs superlattice can be obtained by changing the external applied field. In time-resolved four-wave mixing this implies a change from a third-order polarization signal dominated by phase space occupation to a Coulomb interaction-induced signal when the bias is increased at high excitation densities. The experimental data are compared with theoretical results based on the numerical solution of the semiconductor Bloch equations.
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1371-1375 
    ISSN: 0392-6737
    Keywords: III–V semiconductors ; III–V compounds and systems ; Electron states in low-dimensional structures (including quantum wells, superlattices, layer structures, and intercalation compounds) ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary A photoluminescence study of self-ordered InAs quantum dots grown by molecular beam epitaxy on a GaAs substrate is reported. Short pulses and high excitations have been used in order to observe emission from higher states of the quantum dots. The energy spacing between adjacent transitions seems to be of the order of 40–50 meV for dot diameters around 20 nm. The photoluminescence decay time from the ground state is of the order of 650–700 ps and decreases down to roughly 100 ps for the highest confined states. A cascade-like mechanism for the carrier relaxation in these structures is strongly suggested by the time-resolved data.
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  • 92
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1453-1458 
    ISSN: 0392-6737
    Keywords: Electron states in low-dimensional structures (including quantum wells superlattices, layer structures, and intercalation compounds) ; Other semiconductor-to-semiconductor contacts,p-n junctions, and heterojunctions ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary We consider the intrawell and interwell relaxation of circularly polarized excitons in an asymmetric double-quantum-well structure. For the intrawell case (photocreated light excitons coupled to the detected heavy excitons by an optical-phonon emission) the polarization changes sign after a fast relaxation. For the interwell case (transfer of polarization from the ground heavy exciton of the narrow well towards the ground heavy exciton of the wide well) we observe that the initial polarization is recovered after energy relaxation only if a fast-relaxation path is available which involves only intermediate heavy exciton states.
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  • 93
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1493-1498 
    ISSN: 0392-6737
    Keywords: Electron states in low-dimensional structures (including quantum wells, superlattices, layer structures, and intercalation compounds) ; III-V semiconductors ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary Optical properties of GaAs/Al x Ga1−x As shallow quantum wells have been studied in the 2–200K range, both by c.w. and time-resolved experiments. The results agree with a variational calculation of the excitonic transitions. The LO-phonon-assisted carrier relaxation and a temperature-activated non-radiative channel are evidence.
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  • 94
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1509-1512 
    ISSN: 0392-6737
    Keywords: Excitons and related phenomena (including electron-hole drops) ; III-V Compounds and systems ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary The reflectance spectra of GaN/6H-SiC, films and the absorption spectra of GaN/Al2O3 films were studied and several fundumental parameters of GaN-energy positions of exciton, resonances ω0, damping constants⩾s, longitudinal-transverse splittings ωLT and the oscillator, strengthsf of the exciton states were determined. A blue shift and broadening of the luminescence band were observed in the luminescence spectra of GaN quantum dots. The mean dot radius in the sample was estimated to be about 4.5nm.
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  • 95
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1531-1536 
    ISSN: 0392-6737
    Keywords: Excitons and related phenomena (including electron-hole drops) ; Time-resolved optical spectroscopies and other ultrafast optical measurements in condensed matter ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary The localization dynamics of excitons within growth islands of GaAs/Al x Ga1−x As single quantum wells (SQW) have been investigated by time-resolved photoluminescence spectroscopy (TRPL). Several samples with different substrate misorientation and growth interruption times are compared with regard to the photoluminescence (PL) emission dynamics. For monolayer (ML) islands larger than the exciton radius,i.e. long growth interruption, the time evolution of the different PL peaks reflects the transfer of free excitons between growth islands as well as the localization within a single growth island. The samples with shorter growth interruption reveal a much less pronounced PL splitting due to ML islands. The dynamics appears to be mainly determined by exciton localization to thicker ML islands. The density of localization centres is larger for the sample grown on misoriented substrates.
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  • 96
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1555-1559 
    ISSN: 0392-6737
    Keywords: Nonlinear optics ; Optical properties of thin films, surfaces, and thin layer structures (including superlattices, heterostructures, and intercalation compounds) ; Electron states in low-dimensional structures (including quantum wells, superlattices, layer structures, and intercalation compounds) ; Excitons and related phenomena (including electron-hole drops) ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary In a system comprising an organic layer coupled to a semiconductor layer, if the energy of the Frenkel exciton in the first is close to that of the Wannier exciton in the second, the lowest electronic excitations can be described as hybrid resonances. These new excitons give rise to very pronounced optical non-linearities because they have at the same time large oscillator strengths, typical of Frenkel excitons, and large radii, typical of Wannier excitons. The results of a microscopic calculation of the optical properties of such a system are presented and discussed: compared with the usual semiconductor quantum wells, enhancements of two orders of magnitude both in the size of the susceptibility (linear part) and in its relative change with increasing excitation density (Kerr non-linearity) are predicted.
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  • 97
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1579-1583 
    ISSN: 0392-6737
    Keywords: Electron states in low-dimensional structures (including quantum wells, superlattices, layer structures, and intercalation compounds) ; Other semiconductor-to-semiconductor contacts,p-n junctions, and heterojunctions ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary We report on the calculation of electron and hole states in InAs/GaAs quantum dots. The latters are modelled by cones floating on a wetting layer. The calculations include the effect of an electric field applied parallel to the cone axis as well as the evaluation of the electron-hole correlation and exchange (short-range part) energies.
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  • 98
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1383-1387 
    ISSN: 0392-6737
    Keywords: III–V semiconductors ; Electron states in low-dimensional structures (including quantum wells, superlattices, layer structures, and intercalation compounds) ; Excitons and related phenomena (including electron-hole drops) ; III–V compounds and systems ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary We report an experimental study on a large set of InGaAs/GaAs quantum well structures by means of continuous-wave photoluminescence and photoluminescence excitation. The luminescence spectrum at low temperature systematically exhibits a doublet structure whose lineshape is very sensitive to the excitation energy. Accordingly, the excitation spectra detected by monitoring the emission at the two different luminescence peaks have very different profiles, with peaks and/or dips which are not directly related to absorption resonances. As a matter of fact, the anomalies disappear when increasing the temperature or when using an optical bias with energy above the GaAs energy gap. In these cases, the excitation profiles recover the behaviour typical of 2D systems.
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  • 99
    ISSN: 0392-6737
    Keywords: Excitons and related phenomena (including electron-hole drops) ; Optical properties of thin films surfaces and layer structures (superlattices, heterojunctions and multilayers) ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary We report here on the study of the optical properties of ZnCdSe−ZnSe quantum structures elaborated by metalorganic chemical vapour deposition (MOCVD). The band structure is experimentally investigated by means of photoluminescence and photoreflectance. We have computed the exciton binding energies for heavy- and light-hole excitons in the context of a self-consistent two-parameter trial function. As a complement, we study the temperature dependence of the photoluminescence intensity under both direct and indirect photoexcitation in graded-index separate confinement heterostructures based on these materials.
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  • 100
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    Il nuovo cimento della Società Italiana di Fisica 17 (1995), S. 1595-1599 
    ISSN: 0392-6737
    Keywords: Optical properties of thin films, surfaces, and thin layer structures (including superlattices, heterostructures, and intercalation compounds) ; III-V semiconductors ; Surface and interface electron states ; Conference proceedings
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Summary The optical nonlinearities produced by screening of the piezoelectric field byphotogenerated carriers in a [111]-grown (In, Ga)As/(Al, Ga)As single strained-layer quantum well structure are calculated and compared with those in a [001]-grown structure. Nonlinear absorption and refractive index spectra show that screening of the strain-induced electric field by photo-carriers that have escaped from the [111]-grown quantum well produces optical nonlinearities comparable to those in the more conventional [001]-grown quantum well.
    Type of Medium: Electronic Resource
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