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  • 1
    Electronic Resource
    Electronic Resource
    Tracking and stepping control of the tip position of a scanning tunneling microscope by referring to atomic points and arrays on a regular crystalline surface (1999)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 70 (1999), S. 2053-2059 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: In this article tracking and stepping control of the tip position of a scanning tunneling microscope (STM) by referring to atomic points and arrays on a regular crystalline surface which is used as a two-dimensional reference scale is described. Highly oriented pyrolytic graphite (HOPG) crystal, whose lattice spacing is approximately 0.25 nm, was used as the reference. To utilize the topographic features on the crystalline surface as a reference, a method for determining two-dimensional lateral gradient signals, i.e., the X, and Y axes gradient signals, of the crystalline surface was applied to the control. A rigid STM consisting of a tip scanner and a sample XY stage, and control instruments were developed. The X and Y axes gradient signals were obtained simultaneously using two-phase lock-in modulations of a tunneling current modulated with circular dither motion applied to the tip XY scanner. Modulation frequency and amplitude of the tip were 1 kHz and less than 0.04 nm, respectively. The sample XY stage was controlled for tip positioning by feedback of the X and Y axis gradient signals. First, the tracking control of the STM tip onto an atomic point of the HOPG surface for a maximum duration of about 10 min was performed. Second, tracking and motion control of the STM tip along a crystalline axis of the HOPG surface was demonstrated. The STM tip continued "back and forth" motion along the crystalline axis of the HOPG surface for a maximum duration of 200 s with a maximum tip speed of 6 nm/s. The maximum displacement deviation from the crystalline axis was less than 1/3 lattice spacing (∼0.08 nm). Third, the quantized stepping of the STM tip with lattice spacing stepping with a repetitive rate of 0.5 Hz along the crystalline axis was examined. The maximum displacement deviation from the crystalline axis was less than 1/2 lattice spacing (∼0.12 nm). The feasibility of tracking and stepping control of the STM tip position by referring to atomic points and arrays was confirmed, and the proposed method can be applied to real-time length measurement with subnanometer resolution using a regular crystalline lattice. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1149710
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  • 2
    Electronic Resource
    Electronic Resource
    Long atomic imaging over a 5-μm-long region using an ultralow thermally drifted dual-tunneling-unit scanning tunneling microscope in a thermostabilized cell (1999)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 70 (1999), S. 133-136 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: This article describes the feasibility evaluation of long atomic imaging over a 5-μm-long region for the comparative length measurement using a crystalline lattice as the reference scale and a dual-tunneling-unit scanning tunneling microscope (DTU-STM) as a detector. For suppression of the thermal deformation error, ultralow thermally drifted DTU-STM was developed. The body of the DTU-STM is fabricated from ultralow linear expansion glass and Super-Invar. A thermostabilized cell was utilized to reduce the temperature fluctuation to less than 0.05 K around the DTU-STM. In the thermostabilized cell, the minimum lateral element of thermal drift rate of less than 0.2 nm/h at room temperature was achieved with the DTU-STM. In order to decrease the measurement time and thus reduce the thermal drift error, the fast scanning axis was selected as the direction of the length measurement over the μm range. After attaining thermal equilibrium, a long atomic image of highly oriented pyrolytic graphite over a 5-μm-long region along the fast scanning axis was obtained using the DTU-STM in the thermostabilized cell. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1149554
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  • 3
    Electronic Resource
    Electronic Resource
    Immunoscintigraphy in the detection of tuberculosis with radiolabelled antibody fragment against Mycobacterium bovis bacillus Calmette-Guérin: a preliminary study in a rabbit model (1992)
    Springer
    European journal of nuclear medicine 19 (1992), S. 1011-1015 
    Details
    ISSN: 1619-7089
    Keywords: Immunoscintigraphy ; Tuberculosis ; Mycobacterium bovis bacillus Calmette-Guérin (BCG) ; Rabbit
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Immunoscintigraphy with radiolabelled monoclonal antibodies is widely used to detect solid tumours, but only a few trials have been carried out concerning the specific in vivo localization of an inflammatory process. The purpose of this study was to investigate the detectability of tuberculous foci utilizing this method with radiolabelled bacillus Calmette-Guérin (BCG)-specific F(ab′)2 in rabbits. All of the tuberculous lesions (n=8) were clearly visualized on serial scintigraphy for up to 48 h after injection of the antibody. Immunohistochemical and Ziel-Neelson staining of the tuberculous lesions confirmed the presence of the tuberculous antigens and bacilli. It failed to demonstrate any sustained retention of the BCG-specific antibody fragment in the control group with syphilitic orchitis (n=2). Therefore, the specific in vivo localization of tuberculosis is feasible by immunoscintigraphy.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00180861
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  • 4
    Electronic Resource
    Electronic Resource
    Evaluation of ictal brain SPET using statistical parametric mapping in temporal lobe epilepsy (2000)
    Springer
    European journal of nuclear medicine 27 (2000), S. 1658-1665 
    Details
    ISSN: 1619-7089
    Keywords: Temporal lobe epilepsy Ictal SPET Statistical parametric mapping Subtraction method
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract. An automated voxel-based analysis of brain images using statistical parametric mapping (SPM) is accepted as a standard approach in the analysis of activation studies in positron emission tomography and functional magnetic resonance imaging. This study aimed to investigate whether or not SPM would increase the diagnostic yield of ictal brain single-photon emission tomography (SPET) in temporal lobe epilepsy (TLE). Twenty-one patients (age 27.14±5.79 years) with temporal lobe epilepsy (right in 8, left in 13) who had a successful seizure outcome after surgery and nine normal subjects were included in the study. The data of ictal and interictal brain SPET of the patients and baseline SPET of the normal control group were analysed using SPM96 software. The t statistic SPM{t} was transformed to SPM{Z} with various thresholds of P〈0.05, 0.005 and 0.001, and corrected extent threshold P value of 0.05. The SPM data were compared with the conventional ictal and interictal subtraction method. On group comparison, ictal SPET showed increased uptake within the epileptogenic mesial temporal lobe. On single case analysis, ictal SPET images correctly lateralized the epileptogenic temporal lobe in 18 cases, falsely lateralized it in one and failed to lateralize it in two as compared with the mean image of the normal group at a significance level of P〈0.05. Comparing the individual ictal images with the corresponding interictal group, 15 patients were correctly lateralized, one was falsely lateralized and four were not lateralized. At significance levels of P〈0.005 and P〈0.001, correct lateralization of the epileptogenic temporal lobe was achieved in 15 and 13 patients, respectively, as compared with the normal group. On the other hand, when comparison was made with the corresponding interictal group, only 7 out of 21 patients were correctly lateralized at the threshold of P〈0.005 and five at P〈0.001. The result of the subtraction method was close to the single case analysis on SPM at P〈0.05. However, at higher thresholds (P〈0.005 and 0.001) the subtraction method was comparable to the SPM results only when individual ictal images were compared with the normal control group, and not when comparison was with the interictal group. It is concluded that SPM is an alternative diagnostic method for the localization or lateralization of the seizure focus in temporal lobe epilepsy and that interictal SPET could be omitted if a normal brain SPET database were to be established. The medical cost of seizure localization would thereby be reduced.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002590000364
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  • 5
    Electronic Resource
    Electronic Resource
    Reply (1993)
    Springer
    European journal of nuclear medicine 20 (1993), S. 569-569 
    Details
    ISSN: 1619-7089
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00175173
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  • 6
    Electronic Resource
    Electronic Resource
    Evaluation of cardiac sympathetic neuronal integrity in diabetic patients using iodine-123 metaiodobenzylguanidine (1996)
    Springer
    European journal of nuclear medicine 23 (1996), S. 401-406 
    Details
    ISSN: 1619-7089
    Keywords: Iodine-123 metaiodobenzylguanidine scan ; Cardiac sympathetic nervous function ; Diabetes mellitus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Autonomic dysfunction is associated with increased mortality in diabetic patients. To evaluate the cardiac autonomic dysfunction in these patients, a prospective study was undertaken using iodine-123 metaiodobenzylguanidine (MIBG) single-photon emission tomography (SPET). The study groups consisted of ten diabetic patients with cardiac autonomic neuropathy (group 1) and six without autonomic neuropathy (group II). Autonomic nervous function tests, thallium scan, radionuclide ventriculographic data including ejection fraction and wall motion study, and 24-h urine catecholamine levels were evaluated.123I-MIBG SPET was performed at 30 min and 4 h following injection of 3 mCi of123I-MIBG in groups I and II and in normal subjects (n=4). On planar images, the heart to mediastinum (H/M) ratio was measured. Defect pattern and severity of MIBG uptake were qualitatively analysed on SPET. Compared with control subjects, diabetic patients had a reduced H/M ratio regardless of the presence of clinical autonomic neuropathy. There was no difference in H/M ratio between groups I and II. On SPET images, focal or diffuse defects were demonstrated in all patients in group I, and in five of the six patients in group II. The extent of defects tended to be more pronounced in group I than in group II. In conclusion, SU1-MIBG scan was found to be a more sensitive method than clinical autonomic nervous function tests for the detection of autonomic neuropathy in diabetes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01247368
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  • 7
    Electronic Resource
    Electronic Resource
    Perfusion impairments in infantile autism on technetium-99m ethyl cysteinate dimer brain single-photon emission tomography: comparison with findings on magnetic resonance imaging (1999)
    Springer
    European journal of nuclear medicine 26 (1999), S. 253-259 
    Details
    ISSN: 1619-7089
    Keywords: Key words: Autism ; Brain ; Technetium-99m ethyl cysteinate dimer ; Single-photon emission tomography ; Magnetic resonance imaging
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract. The neuro-anatomical substrate of autism has been the subject of detailed investigation. Because previous studies have not demonstrated consistent and specific neuro-imaging findings in autism and most such studies have been performed in adults and school-aged children, we performed a retrospective review in young children in search of common functional and anatomical abnormalities with brain single-photon emission tomography (SPET) using technetium-99m ethyl cysteinate dimer (ECD) and correlative magnetic resonance imaging (MRI). The patient population was composed of 23 children aged 28–92 months (mean: 54 months) who met the diagnostic criteria of autism as defined in the DSM-IV and CARS. Brain SPET was performed after intravenous injection of 185–370 MBq of 99mTc-ECD using a brain-dedicated annular crystal gamma camera. MRI was performed in all patients, including T1, T2 axial and T1 sagittal sequences. SPET data were assessed visually. Twenty patients had abnormal SPET scans revealing focal areas of decreased perfusion. Decreased perfusion of the cerebellar hemisphere (20/23), thalami (19/23), basal ganglia (5/23) and posterior parietal (10/23) and temporal (7/23) areas were noted on brain SPET. By contrast all patients had normal MRI findings without evidence of abnormalities of the cerebellar vermis, cerebellar hemisphere, thalami, basal ganglia or parietotemporal cortex. In conclusion, extensive perfusion impairments involving the cerebellum, thalami and parietal cortex were found in this study. SPET may be more sensitive in reflecting the pathophysiology of autism than MRI. However, further studies are necessary to determine the significance of thalamic and parietal perfusion impairment in autism.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002590050385
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  • 8
    Electronic Resource
    Electronic Resource
    Evaluation of cardiac adrenergic neuronal damage in rats with doxorubicin-induced cardiomyopathy using iodine-131 MIBG autoradiography and PGP 9.5 immunohistochemistry (2000)
    Springer
    European journal of nuclear medicine 27 (2000), S. 686-693 
    Details
    ISSN: 1619-7089
    Keywords: Key words: Cardiomyopathy ; Doxorubicin ; Iodine-131 metaiodobenzylguanidine ; Immunohistochemistry ; Protein gene product 9.5
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract. Doxorubicin is one of the most useful anticancer agents, but its repeated administration can induce irreversible cardiomyopathy as a major complication. The purpose of this study was to investigate doxorubicin toxicity on cardiac sympathetic neurons using iodine-131-metaiodobenzylguanidine (MIBG) and protein gene product (PGP) 9.5 immunohistochemistry, which is a marker of cardiac innervation. Wistar rats were treated with doxorubicin (2 mg/kg, i.v.) once a week for 4 (n=5), 6 (n=6) or 8 (n=7) weeks consecutively. Left ventricular ejection fraction (LVEF), calculated by M-mode echocardiography, was used as an indicator of cardiac function. Plasma noradrenaline (NA) concentration was measured by high-performance liquid chromatography (HPLC). 131I-MIBG uptake of the left ventricular wall (24 ROIs) was measured by autoradiography. 131I-MIBG uptake pattern was compared with histopathological results, the neuronal population on PGP 9.5 immunohistochemistry and the degree of myocyte damage assessed using a visual scoring system on haematoxylin and eosin and Masson’s trichrome staining. LVEF was significantly decreased in the 8-week group (P〈0.05). The serum NA level also showed no statistical difference until 4 weeks and was significantly increased in the 8-week group (P〈0.05). MIBG uptake was decreased in the 6- and 8-week groups (P〈0.05), and was closely correlated with the reduction in the number of nerve fibres on PGP 9.5 stain. Myocyte damage was seen only in the 8-week group. Neuronal population and the 131I-MIBG uptake ratio of subepicardium to subendocardium were significantly increased (P〈0.05) in the 8-week group as compared with the control group. It may be concluded that radioiodinated MIBG is a reliable marker for the detection of cardiac adrenergic neuronal damage in doxorubicin-induced cardiomyopathy; it detects such damage earlier than do other clinical parameters and in this study showed a good correlation with the reduction in the neuronal population on PGP 9.5 stain. The subendocardial layer appeared to be more vulnerable to doxorubicin than the subepicardium.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002590050563
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  • 9
    Electronic Resource
    Electronic Resource
    Treatment of Bowen’s disease with a specially designed radioactive skin patch (2000)
    Springer
    European journal of nuclear medicine 27 (2000), S. 842-846 
    Details
    ISSN: 1619-7089
    Keywords: Key words: Bowen’s disease ; Radiotherapy ; Radionuclide ; Holmium-166 skin patch
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract. Bowen’s disease can be treated by various methods, including surgical excision, cryosurgery, laser ablation, curettage, Mohs’ microsurgery and ionizing radiation. Radiotherapy has been a useful therapeutic modality in the treatment of Bowen’s disease and other skin cancers in areas which are difficult to excise, especially the central areas of the face, including eyelids, nose and lips. To overcome some of the disadvantages of external radiotherapy, a specially designed skin patch coated with high-energy beta-emitter holmium-166 was made for topical application at our institute. Twenty-nine sites of Bowen’s disease in eight patients, confirmed by skin biopsy, were treated with 166Ho patches. The patches were applied to the surface of skin cancers for 30–60 min for a total radiation dose of 35 Gy (3500 rads). One to two weeks after application of the 166Ho patch, desquamation, erythema or erosion developed in treated sites, but these acute radiation reactions healed gradually with epithelial regeneration, and they showed good functional and cosmetic results without any complications. Follow-up biopsies were performed 1–5 months after 166Ho patch therapy, and they did not show any signs of Bowen’s disease. One to two years after treatment with 166Ho skin patches, there were no recurrences of Bowen’s diseases and no late complications. The 166Ho patch is an effective and convenient alternative method for the treatment of Bowen’s disease that yields good cosmetic and functional results.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002590000262
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  • 10
    Electronic Resource
    Electronic Resource
    Synthesis and characterization of biodegradable poly(L-aspartic acid-co-PEG) (1998)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2949-2959 
    Details
    ISSN: 0887-624X
    Keywords: aspartic acid anhydride ; poly(ethylene glycol) ; poly(L-aspartic acid-co-PEG) ; biodegradable polymers ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The melt polycondensation reaction of the prepolymer prepared from N-(benzyloxycarbonyl)-L-aspartic acid anhydride (N-CBz-L-aspartic acid anhydride) and low molecular weight poly(ethylene glycol) (PEG) using titanium isopropoxide (TIP) as a catalyst produced the new biodegradable poly(L-aspartic acid-co-PEG). This new copolymer had pendant amine functional groups along the polymer backbone chain. The optimal reaction conditions for the preparation of the prepolymer were obtained by using a 0.12 mol % of p-toluenesulfonic acid with PEG 200 for 48 h. The weight-average molecular weight of the prepolymer increased from 1,290 to 31,700 upon melt polycondensation for 6 h at 130°C under vacuum using 0.5 wt % TIP as a catalyst. The synthesized monomer, prepolymer, and copolymer were characterized by FTIR, 1H- and 13C-NMR, and UV spectrophotometers. Thermal properties of the prepolymer and the protected copolymer were measured by DSC. The glass transition temperature (Tg) of the prepolymer shifted to a significantly higher temperature with increasing molecular weight via melt polycondensation reaction, and no melting temperature was observed. The in vitro hydrolytic degradation of these poly(L-aspartic acid-co-PEG) was measured in terms of molecular weight loss at different times and pHs at 37°C. This pH-dependent molecular weight loss was due to a simple hydrolysis of the backbone ester linkages and was characterized by more rapid rates of hydrolysis at an alkaline pH. These new biodegradable poly(L-aspartic acid-co-PEG)s may have potential applications in the biomedical field. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2949-2959, 1998
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
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