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101.
Tadaaki Yokota Tokuhiro Ishihara Hiroo Kawano Mutsuo Takahashi Yoshimi Yamashita Toshikazu Gondo Yoshihiro Fujinaga Fumiya Uchino 《Pathology international》1989,39(6):349-355
Amyloid enhancing factor (AEF) was extracted from spleens of mice that had received amyloidogenic stimulation. Sephacryl S 300 gel filtration of the crude AEF yielded five fractions, among which strong AEF activity was present in the first peak (Fl), and confirmed by an amyloid induction experiment. An anti AEF antiserum was obtained from a rabbit by immunization with Fl. This antibody reacted strongly with splenic polymorphonuclear leukocytes (PML) from mice given amyloidogenic stimulation, and weakly with those from normal untreated mice. Isoelectric focusing (IEF) analysis of both Fl and sera from mice given amyloidogenic stimulation was performed. A single band was observed on IEF analysis of Fl, whereas many bands were seen on IEF analysis of the sera. After the substances in the gel had been transferred to nitrocellulose membranes by capillary blotting, the membranes were made to react with the anti-AEF antiserum. The results suggested that AEF is a high molecular-weight substance derived from PML and increases in the serum at the time of, or shortly prior to, amyloid deposition in the spleen. Acta Pathol Jpn 39: 349∼355, 1989. 相似文献
102.
Mutsuo Takahashi Tadaaki Yokota Tokuhiro Ishihara Fumiya Uchino Tbshiaki Kamei 《Ultrastructural pathology》1986,10(3):235-240
Amyloid depositions of pancreatic islets were investigated with electron microscopy in a case of type III glycogenosis.
Beta cells adjoining small amyloid depositions were shown to have cytoplasmic invaginations where closely packed amyloid fibrils were disclosed regularly orientated amyloid bundles. In the cytoplasm of the beta cells, some membrane-bounded vesicles contained amyloid fibrils and a few beta granules directly transformed into the fibrils within the vesicles.
These findings indicate that, at least in this case, the beta cells play a crucial role in the formation of insular amyloid. 相似文献
Beta cells adjoining small amyloid depositions were shown to have cytoplasmic invaginations where closely packed amyloid fibrils were disclosed regularly orientated amyloid bundles. In the cytoplasm of the beta cells, some membrane-bounded vesicles contained amyloid fibrils and a few beta granules directly transformed into the fibrils within the vesicles.
These findings indicate that, at least in this case, the beta cells play a crucial role in the formation of insular amyloid. 相似文献
103.
Masafumi Hara Yutaka Tsutsumi Keiichi Watanabe Sohtaro Suzuki Norio Tani Takeshi Miwa 《Pathology international》1985,35(4):831-840
Six solitary gastric polyps in the acid-secreting fundic mucosa were histo-chemically investigated using the mucin histochemistry, immunoperoxidase method, and silver methods for endocrine cells. Histologically, the polyps were grouped into three types : they largely consisted of either hyperplastic foveolar cells (group 1), normal-appearing fundic gland cells with mild cystic changes (group 2) or hyperplastic fundic gland cells with cystic dilatation (group 3). The presence of parietal cells and mucous neck cells was confirmed in all polyps by the immunoperoxidase method using parietal cell autoantibody and the paradoxical Concanavalin A staining, respectively. Regarding the endocrine component, somatostatin-containing cells, Grimelius-positive argyrophil cells, and Fontana-Masson-positive enterochromaffin cells were scattered in the fundic gland area of the polyps as well as in the surrounding normal-appearing fundic mucosa. Gastrin-containing cells were absent. In one of the group 2 polyps and both group 3 polyps, a varying number of glicentin-containing cells were found among the fundic gland components : In one polyp in group 3, glucagon immunoreactivity was detected in the glicentin-containing cells. These findings suggest that some of the polyps express characteristics of the fetal fundic mucosa, since glicentin and glucagon immunoreactivities in normal human stomach have been detected exclusively in the fetal fundus. ACTA PATHOL. JPN. 35: 831–840, 1985. 相似文献
104.
Some patients with bronchial asthma have increased cough sensitivity. In such patients coughing may be an inducer of wheeze. The aim of the present study was to investigate the effect of Bakumondo-to on the cough sensitivity and respiratory tract inflammation in asthmatic patients with increased cough sensitivity. In addition influences of intensity of respiratory tract inflammation, gender, type of asthma, and disease period on the effect of Bakumondo-to on the cough sensitivity were examined. Twenty-one bronchial asthmatics whose cough thresholds to capsaicin were less than 3.9 microM were examined. METHODS: Cough thresholds to capsaicin (concentration of inhaled capsaicin solution causing 5 or more coughs) was measured before and after 2 months or more treatment with Bakumondo-to (9 g/day, TJ-29). Number of eosinophils in peripheral blood, sputum eosinophil ratio, and ECP level in the serum were also measured before and after treatment. RESULTS: Bakumondo-to significantly increased the cough threshold. Although respiratory tract inflammation was not significantly improved, number of eosinophils in peripheral blood, sputum eosinophil ratio and ECP level in the serum were remarkably decreased more than the half. And Bakumondo-to was more effective in asthmatic subjects with severe airway inflammation. Furthermore, a greater effect of it was observed in women. A greater effect was also observed in patients having a disease duration of less than 1 year. CONCLUSION: Our results suggest that Bakumondo-to may be an effective therapeutic preparation for coughing in asthmatic patients with cough hypersensitivity. 相似文献
105.
Toll-like receptor 9 is expressed on follicle-associated epithelia containing M cells in swine Peyer's patches 总被引:3,自引:0,他引:3
Shimosato T Tohno M Kitazawa H Katoh S Watanabe K Kawai Y Aso H Yamaguchi T Saito T 《Immunology letters》2005,98(1):83-89
The precise distribution and expression of Toll-like receptor (TLR) 9 in gut-associated lymphoid tissues (GALTs) has not been elucidated. In this study, we investigated the expression pattern of TLR9 in adult and neonatal swine GALTs by real-time quantitative PCR, western blot, confocal laser microscopy and flow cytometric analysis. The swine TLR9 gene was preferentially expressed in adult Peyer's patches (Pps) and mesenteric lymph nodes (MLNs), which contained approximately three times higher TLR9 than the spleen. Other tissues exhibited only weak expression of TLR9. In neonatal swine, elevated expression of TLR9 was detected only in MLNs. We firstly showed that highly expressive (TLR9(+)) cells were formed in Pps and MLNs. In addition, TLR9(+) cells were present not only in immune cells such as dendritic cells and B cells but also in follicle-associated epithelia (FAE) including membranous cells (M cells) in Pps. These results suggest that Pps and MLNs provide the host defense with the ability to respond to a variety of bioactive oligonucleotides (ODNs) from bacteria at a conductive site of initial immune responses. 相似文献
106.
Katsumi Inoue Kenichi Abe Kenji Ando Shinichi Shirai Kei Nishiyama Michio Nakanishi Takashi Yamada Koyu Sakai Yoshihisa Nakagawa Naoya Hamasaki Takeshi Kimura Masakiyo Nobuyoshi Tadaomi Alfonso Miyamoto 《Cardiovascular pathology》2004,13(2):109-115
BACKGROUND: Angiographic regression of luminal narrowing occurs 6 months to 3 years poststenting. However, after 4 years lesions progressed gradually and late restenosis was observed in 28% of 179 Palmaz-Schatz-stented lesions during the past 10 years. Elucidating its pathogenesis is pivotal to developing preventive strategies. METHODS AND RESULTS: Histopathological and immunohistochemical studies were performed in 19 stented coronary arteries obtained from 19 patients autopsied after noncardiac death 2-7 years poststenting. The quality/severity of chronic inflammatory cells (T lymphocytes, macrophages and multinucleated giant cells) infiltration around the stent struts that is observed even in the absence of restenosis depended on the time elapsed from stenting: a) 2 years postprocedure, in spite of angiographic regression during the first year and pathologically expressed as maturation of the neointimal scar, there was chronic inflammatory response evidence: neovascularization and lymphocyte infiltration, b) > or = 3 years: the neointimal smooth muscle cells were sparse with abundant proliferation of collagen fibers. Presence of slight helper/inducer T lymphocytes and mild macrophage infiltration around the stent struts was evident immunohistochemically, c) > or = 4 years: prominent infiltration by lipid-laden macrophages with strong collagen-degrading matrix metalloproteinase immunoreactivity was observed around the struts. In two of these arteries, the surface contacting the stent was focally disrupted and covered by nonocclusive mural thrombi. CONCLUSIONS: Stainless steel stents evoke a remarkable foreign-body inflammatory reaction to the metal. These persistent peri-strut chronic inflammatory cells may accelerate new indolent atherosclerotic changes and consequent plaque vulnerability. 相似文献
107.
Fujita M Ishihara M Simizu M Obara K Ishizuka T Saito Y Yura H Morimoto Y Takase B Matsui T Kikuchi M Maehara T 《Biomaterials》2004,25(4):699-706
Addition of various heparinoids to the lactose-introduced, water-soluble chitosan (CH-LA) aqueous solution produces an injectable chitosan/heparinoid hydrogel. In the present work, we examined the capability of the chitosan/non-anticoagulant heparin (periodate-oxidized (IO(4)-) heparin) hydrogel to immobilize fibroblast growth factor (FGF)-2, as well as the controlled release of FGF-2 molecules from the hydrogel in vitro and in vivo. The hydrogel was biodegraded in about 20 days after subcutaneous injection into the back of a mouse. When the FGF-2-incorporated hydrogel was subcutaneously injected into the back of both mice and rats, a significant neovascularization and fibrous tissue formation were induced near the injected site. These results indicate that the controlled release of biologically active FGF-2 molecules is caused by biodegradation of the hydrogel, and that subsequent induction of the vascularization occurs. 相似文献
108.
Rapid serodiagnosis of active pulmonary Mycobacterium tuberculosis by analysis of results from multiple antigen-specific tests 总被引:5,自引:0,他引:5 下载免费PDF全文
Okuda Y Maekura R Hirotani A Kitada S Yoshimura K Hiraga T Yamamoto Y Itou M Ogura T Ogihara T 《Journal of clinical microbiology》2004,42(3):1136-1141
We have prospectively analyzed three antigens for serodiagnosis of tuberculosis (TB). These antigens were tuberculous glycolipid antigen, lypoarabinomannan polysaccharide antigen, and antigen 60 (A60), which was derived from purified protein derivatives. Of the 131 patients with active pulmonary TB, 57 were both smear and culture negative and 14 had chronic active pulmonary TB that remained smear positive for >12 months of chemotherapy. One hundred twenty healthy adults were controls. The percentages of patients positive in all three tests were 58.8% for smear-positive active pulmonary TB and 71.4% for chronic active pulmonary TB. When the results of the three serodiagnostic tests were evaluated in combination, the sensitivity increased to 91.5% in patients with active pulmonary TB and to 86.0% in smear- and culture-negative patients. The false-positive rate of the three-test combination was 12.5% in the healthy control groups. In conclusion, it was not possible to detect all of the antibodies against antigenic substances in the cell walls of the tuberculous bacilli in the sera of all TB patients by using available serodiagnostic tests. However, the combined use of tests with three separate antigens maximizes the effectiveness of serodiagnosis. 相似文献
109.
Mostly separate distributions of CLAC- versus Abeta40- or thioflavin S-reactivities in senile plaques reveal two distinct subpopulations of beta-amyloid deposits 下载免费PDF全文
Kowa H Sakakura T Matsuura Y Wakabayashi T Mann DM Duff K Tsuji S Hashimoto T Iwatsubo T 《The American journal of pathology》2004,165(1):273-281
Collagenous Alzheimer amyloid plaque component (CLAC) is a unique non-Abeta amyloid component of senile plaques (SP) derived from a transmembrane collagen termed CLAC-precursor. Here we characterize the chronological and spatial relationship of CLAC with other features of SP amyloid in the brains of patients with Alzheimer's disease (AD), Down syndrome (DS), and of PSAPP transgenic mice. In AD and DS cerebral cortex, CLAC invariably colocalized with Abeta42 but often lacked Abeta40- or thioflavin S (thioS)-reactivities. Immunoelectron microscopy of CLAC-positive SP showed labeling of fibrils that are more loosely dispersed compared to typical amyloid fibrils in CLAC-negative SP. In DS cerebral cortex, diffuse plaques in young patients were negative for CLAC, whereas a subset of SP became CLAC-positive in patients aged 35 to 50 years, before the appearance of Abeta40. In DS cases over 50 years of age, Abeta40-positive SP dramatically increased, whereas CLAC burden remained at a constant level. In PSAPP transgenic mice, CLAC was positive in the diffuse Abeta deposits surrounding huge-cored plaques. Thus, CLAC and Abeta40 or thioS exhibit mostly separate distribution patterns in SP, suggesting that CLAC is a relatively early component of SP in human brains that may have inhibitory effects against the maturation of SP into beta-sheet-rich amyloid deposits. 相似文献
110.
Kawano F Wang XD Lan YB Yoneshima H Ishihara A Igarashi M Ohira Y 《The Japanese journal of physiology》2004,54(3):229-242
Effects of 9-week hindlimb suspension and 8-week recovery on air-righting reaction in response to drop from a supine position were studied in adult rats. The righting time in rats at the end of suspension (approximately 220 ms) was longer than the age-matched controls (approximately 120 ms, p <0.05). The unloading-related change in righting time was accompanied by lowered activities of electromyogram (EMG) and altered recruitment of both neck and back muscles at a specific stage of drop. After 8 weeks of reambulation, righting time recovered toward the control level (approximately 153 ms, p <0.05), but the EMG activity of back muscle was still less than controls. In contrast, the EMG of neck muscle during fall was even increased. The differences in the characteristics of the muscle fibers between two groups were minor. It is suggested that inhibition of recruitment, rather than the changes in the fiber characteristics, of neck and back muscles is one of the major causes of the slow air-righting. 相似文献