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21.
I briefly review spheroids observed in the anterior horns of the spinal cord in amyotrophic lateral sclerosis (ALS). Spheroids are argentophilic bodies more than 20 μm in diameter. Recently, some connections between the proximal axonal swellings including spheroids and the perikarya have been reported in some ALS patients with a short clinical course or mild depletion of anterior horn neurons. Most of the cell bodies directly connected with the axonal swellings appear normal, and spheroids are considered to be one of the hallmarks of the early histological changes in this disorder. Spheroids are strongly positive with anti-phosphorylated neurofilament antibody, and are also positive with calcitonin gene-related peptide and anti-peripherin antibody. Some spheroids are immunostained with anti-synaptophysin antibody and anti-ubiquitin antibody. Spheroids are not immunostained with anti-phosphorylated tau antibody, or high molecular weight microtubule associated proteins. Electron microscopically, spheroids are usually composed of densely packed accumulation of 10 nm neurofilaments with a variety of orientations, plus vesicles, dense bodies and mitochondria. When the swellings of the initial segment is relatively pronounced, the undercoating is obscured and the neurofilaments become interwoven in some parts. In the first internode of the myelinated axons, as the swellings become larger, the neurofilaments lose their parallel orientation and become intermingled. Large accumulation of neurofilaments resembling spheroids in the perikarya of large anterior horn cells suggests that spheroids could be derived not only from the axon including the proximal portion, but also from the perikarya. Structures apparently identical to axonal spheroids are observed at the light and electron microscopic levels in the proximal portion of axons of anterior horn cells in animal models intoxicated with β, β'-iminodipropionitrile (IDPN), or with aluminum, in hereditary canine spinal muscular atrophy (HCSMA). The pathogenetic mechanism is probably associated with an impairment in slow axonal transport which particularly affects the neurofilaments in IDPN and aluminum intoxication. Impairment of slow axonal transport of neurofilaments also plays an important role in the pathogenesis of ALS. The average diameter of even normalappearing initial segment is larger in ALS than in the controls. The perikarya connected with the swollen proximal axons and their dendrites almost always appear normal. These findings suggest that the slow axonal transport of neurofilaments is probably impaired in this portion of the axon at an early stage in ALS as well as animal models for human ALS. However, techniques to analyze slow axonal transport in humans still remain tobe developed. Recently, overexpression of neurofilament subunits in transgenic mice produces a condition resembling ALS. The transgenic model may offer an interesting perspective not only for testing therapeutic strategies but also for investigating in a systematic way the various genetic and environment factors controlling the onset and progression of the disease and might yield new insights on the etiology of ALS.  相似文献   
22.
The effects of FUT-187 (6-amidino-2-naphthyl 4-[(4,5-dihydro-1H-imidazol-2-yl)amino]benzoate dimethanesulfonate, CAS 103926-82-5), a novel synthetic protease inhibitor, were examined in experimental rat and canine models of pancreatitis. 1. FUT-187 significantly increased the survival of rats with trypsin- and phospholipase A2-induced pancreatitis in a dose-dependent manner (10-100 mg/kg, p.o.). 2. FUT-187 decreased plasma enzymatic activity reflecting the degree of pancreatitis in rats with ethionine-induced pancreatitis, and showed a tendency to ameliorate histopathological changes in the pancreas (10-100 mg/kg p.o.). 3. FUT-187 (10 mg/kg) produced an obvious improvement of various biochemical parameters of pancreatitis and also reduced histopathological changes in the pancreas in animals with experimental pancreatitis produced by the closed duodenal loop method. In addition, FUT-187 significantly increased the survival of dogs when given by direct administration into the lumen of the closed duodenal loop. The therapeutic effects of FUT-187 in experimental pancreatitis were nearly equal in most instances to those of camostat mesilate. Thus, FUT-187 would appear to be an effective new agent for the treatment of pancreatitis.  相似文献   
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Diurnal changes of serotonin-related factors in whole blood and fibrinolytic activity were determined in depressed patients and healthy controls. Whole blood serotonin concentration of depressed patients showed marked changes throughout daytime, with maximum values in the evening and lowest values in the morning, whereas its metabolite 5-HIAA followed a contrary pattern. The circadian rhythm of 5-HT and 5-HIAA in the control group was quite different from depressed patients. Plasma levels of tPA decreased from 12:30 to 16:30. Concentrations of free plasminogen activator inhibitor (PAI-1) and complex of tPA-PAI-1 decreased from 8:30 to 16:30. Plasma levels of total PAI-1 decreased from 8:30 to 16:30. Plasma levels of the fibrinolytic parameters may be lower in depressive patients than in normal controls. These results support the changes in the circadian rhythm of serotonin and its related substances in the blood of depressive patients.  相似文献   
25.
Ninety-one patients with operation history for urotheliomas were followed-up by urinary cytology for 17.5 months on the average. Cytologically, fresh urine was examined every month and vesical irrigation fluid every three months. Cystoscopy was also performed every three months, IVP every six months, and biopsy was performed when carcinoma or dysplasia was suspected. As a result, cases were classified into four groups. Group 1: All cytological examination were negative. Group 2: Cytology was positive for two or three months after TUR-Bt during which period vesical instillation therapy of anti-cancer drugs was performed, but was negative after this period. Group 3: Positive and negative cytology were diagnosed irregularly. Group 4: All cytological examinations were positive. The numbers of cases classified into these groups were 27 (29.7%), 7 (7.7%), 43 (47.3%) and 14 (15.4%), respectively. Tumor recurrence was seen in 1/27 (3.7%), 0/7, 12/43 (27.9%) and 4/14 (28.6%) cases, respectively. Metastasis was seen in only five cases of the group 4. Tumor recurrence and positive urinary cytology at the same time were seen in nine cases (20.9%) of group 3, and eight cases (57.1%) of group 4. Thirty four cases (79.1%) with discrepancy of cytological and endoscopic findings in group 3, in which cases 20 cases had only positive irrigation cytology and 11 cases had positive fresh urine and irrigation specimens, were more suspicious of temporary existence of in situ carcinomas or dysplastic urothelium. Of six cases with the discrepancy in group 4, three cases were in situ carcinoma diagnosed by random biopsies, and four cases had positive cytologies after TUR-Bt continuously.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
26.
From January 1986 to December 1988, a prospective trial of transcatheter arterial treatment was carried out for hepatocellular carcinoma (HCC). Two hundred seventy-five patients were included. Okuda's staging system was employed. Patients with Stage I and II HCC were treated by transcatheter arterial embolization (TAE) with a gelatin sponge containing an anti-cancer agent (protocol 1a); a gelatin sponge and iodized oil mixed with an anti-cancer agent (protocol 1b); or iodized oil mixed with an anti-cancer agent (protocol 2). Patients with Stage III HCC were treated with iodized oil with anti-cancer agent (protocol 2). As an exception, patients with an unsuccessful superselective catheterization into the proper hepatic artery by Seldinger technique or obstruction of the main trunk of the portal vein were treated with percutaneous transcatheter arterial infusion into the common hepatic artery regardless of stage (protocol 3). Tumor type and extension, area of tumor involvement, portal vein involvement, method of treatment, and presence of ascites and icterus were found to be the significant factors for an initial response to therapy. Treatment method was the most important factor. Respective survival rates at 1 and 2 years were 70.9% and 55.3% for protocol 1a; 62.3% and 43.8% for protocol 1b; 37.8% and 18.3% for protocol 2; and 16.5% and 0% for protocol 3. Many factors proved to significantly influenced prognosis; however, tumor type had the most important prognostic significance followed by AFP value, ascites, treatment protocol, and area of tumor involvement.  相似文献   
27.
Although aortic valve replacement (AVR) is an effective treatment for patients with aortic valvular disease, the implantation of a small aortic prosthesis may result in residual left ventricular outflow stenosis and transvalvular gradient. In this study, the outcome in the long-term period of patients treated with a small aortic prosthesis was analyzed retrospectively. Twenty-four patients with AVR were divided into two groups, group A and group B. Group A consisted of 16 patients with 21 mm-sized prosthetic valves, and group B consisted of 8 patients with 19 or 16 mm-sized prosthetic valves. There were no significant differences in preoperative cardiac function or operative procedure in the two groups. The mean follow-up period (months) was 55.0 in group A and 51.3 in group B. RESULTS: One patient died of cerebral infarction in group A. There were no significant differences in cardiothoracic ratio (CTR), left ventricular ejection fraction (LVEF), and left ventricular mass index (LVMI) between the two groups. Postoperative physical activity according to the New York Heart Association (NYHA) classification showed no significant differences in the two groups. Despite using a small prostheses for AVR, the postoperative course was good in the long-term period, although careful follow-up is necessary.  相似文献   
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We studied functional and immunohistochemical characteristics of cultured rat microglia. Unstimulated microglia did not proliferate. Microglia stimulated with LCM (L929 conditioned medium: colony stimulating factor-1) had proliferative activity and increased acid phosphatase activity. LPS (lipopolysaccharide) and IFN gamma (interferon-gamma) but did not affect proliferative activity. Immunohistochemically, RCA-1 lectin and GS-1 lectin, which react to beta-D-galactose and alpha-D-galactose respectively, strongly reacted to the cytoplasm and membrane of unstimulated microglia. After stimulation with LCM, microglia elongated processes and decreased response to these lectins. On the other hand, microglia stimulated with LCM showed increased reactivity to monoclonal antibody of vimentin. Microglia stimulated with LPS had round shape and had response to these lectins and vimentin. Microglia stimulated with IFN gamma had adhesive activity and weakly stained with these lectins but not with vimentin. ED-1 (monoclonal antibody of rat monocytes/macrophages) reacted to unstimulated and stimulated microglia. In flow cytometry, unstimulated microglia expressed OX-18 (MHC class I) and W3/25 (CD4) antigen. After stimulation with IFN gamma, microglia were induced to express these antigens. CD4 antigen is a marker of helper/inducer T cells and thought to be a receptor of HIV. The results that microglia had CD4 antigen which was further induced with IFN gamma are important to investigate infection of the CNS with HIV. OX-6 (Ia) antigen was induced with IFN gamma. This indicates that the microglia plays a central role in the CNS immune reaction. These characteristics of cultured rat microglia provide useful informations to investigate the pathogenesis of the CNS disorders.  相似文献   
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