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81.
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   
82.
Background: The Ki-67 antigen appears in all human proliferating cells during late G1, S, M and G2 phases of the cell cycle, but is consistently absent in the Go phase (noncycling) cells. The correlation between Ki-67 in the brainstem and sleep apnea in victims of the sudden infant death syndrome (SIDS) was investigated to elucidate cell kinetics in the brainstem of this condition, which is still the main cause of postneonatal infant death. Materials and methods: Twenty-six cases of SIDS occurred among 38 infants dying under 6 months of age in a cohort of 27,000 infants studied prospectively to characterize their sleep–wake behavior. All the infants had been recorded during one night in a pediatric sleep laboratory some 3–12 weeks before death. The frequency and duration of sleep apnea were analyzed. At autopsy, brainstem material was collected and immunohistochemistry for Ki-67 was carried out. The density of Ki-67-positive neurons was measured semiquantitatively. Correlation analyses were carried out between the density of Ki-67-positive neurons and the data on sleep apnea. Results: Except in two cases in SIDS victims and in one control, the detection of Ki-67 was negative. No correlation analysis between the Ki-67 and of sleep apnea was found. Conclusions: There were no abnormal cell kinetics detected by the demonstration of Ki-67 antigen in the brainstems of SIDS victims.  相似文献   
83.
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   
84.
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   
85.
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   
86.
Human parvovirus B19 (B19) infects cells of erythroid lineage. Production of neutralizing antibodies (Abs) is indispensable for recovery from B19-related disease state. In this study, we used a convenient method to measure neutralizing activities in human sera by using a real-time quantitative PCR based assay. Erythroid cell line KU812Ep6 was incubated with test sera before infection with B19 virus. The copy number of B19-DNA in cultures was decreased in the presence of the sera from patients who recovered from acute B19 infection, whereas no decrease in B19-DNA was in cultures incubated with sera from healthy volunteers who had no B19 infection. The decrease in B19-DNA copy number was calculated and the inhibition percentage was expressed as neutralizing activity to B19. A clinical study showed that the levels of neutralizing ability were high in patients who recovered soon after acute B19 infection, but were low in some patients with a prolonged clinical course for recovery from B19 infection. This method is simple and convenient compared with methods described previously, showing its usefulness to evaluate the neutralizing activity to B19.  相似文献   
87.
The diagnosis of rheumatic diseases is primarily based on clinical symptoms and laboratory findings. However, diagnosis of rheumatic disease is often difficult because of the variations even in the same disease. Routine laboratory tests are valuable in detecting renal dysfunctions. In this review, the important auto-antibodies and inflammatory markers associated with rheumatic diseases are described. Further, their utility as diagnostic and prognostic tools, including their specificity, sensitivity and practical applications, is discussed.  相似文献   
88.
Human luteal cells have been reported to express human leukocyteantigen-DR and lymphocyte functional antigen-3 on the cell surface,suggesting physiological interaction between luteal cells andT-lymphocytes through the menstrual cycle into early pregnancy.To elucidate the role of peripheral lymphocytes on corpus luteumdifferentiation, the effect of peripheral blood mononuclearcells (PBMC) on steroidogenesis by luteal cells was investigated.The production of Th-2 cytokines such as interleukin (IL)-4and IL-10 by the co-cultured cells was also examined, and theeffects of these cytokines on progesterone production by lutealcells were investigated. Corpora lutea were obtained from eightnon-pregnant women in the luteal phase and five women in earlypregnancy for luteal cell culture. PBMC were isolated from unrelatedwomen in the follicular phase, secretory phase, and early pregnancy.After co-culture with allogenic PBMC for 48 h, progesteroneproduction was significantly enhanced by PBMC from the secretoryphase and early pregnancy in the non-pregnant luteal cell culture.In the pregnant luteal cell culture, a significant increasein progesterone production was also observed by the co-culturewith PBMC from women in early pregnancy, showing that PBMC havea luteotrophic effect. The stimulatory effects of PBMC werealso observed in co-culture conditions which prevented directcell-to-cell interaction with luteal cells, showing the minorinfluence of mixed lymphocyte reaction. By co-culture with PBMC,the production of IL-10, but not IL-4, was significantly augmentedin luteal cell culture derived from non-pregnant women, whereasthe production of both IL-4 and IL-10 was significantly enhancedin the luteal cell culture derived from pregnant women. Moreover,IL-4 and IL-10 promoted progesterone production by culturedluteal cells, especially in the luteal cell culture derivedfrom corpora lutea of early pregnancy. These findings indicatethat PBMC stimulate progesterone production by luteal cellsand suggest the involvement of PBMC in corpus luteum functionand differentiation probably via the Th-2-type lymphocytes.  相似文献   
89.
Two cell lines designated IC KMS and D KMS were established from human adenovirus type 12 induced tumors of C3Hf/OK mouse. The cell lines retained the characteristics of the original tumor i.e., production of numerous C type and intracisternal A-type particles, integration of Adl2 El region DNA and amplification of the myc gene family. Chromosomal analysis revealed chromosome aberrations in both IC KMS and D KMS cells. The modal chromosome number of IC KMS cells was 54 and that of D-KMS cells was 48. Metacentric chromosomes and mini-chromosomes were found. Trisomy of chromosome 3, 7 and 12 was seen frequently in D KMS cells. Although DNA aneuploidy was revealed by flow cytometry, the DNA indices of these cells showed no relation to the copy number of integrated Adl2 DNA. These cells have been propagated by serial culture during the past 17 months. Production of endogenous virus particles is a unique characteristic of IC KMS and D KMS cells. These cell lines would be useful materials for examining the contribution of Adl2 carcinogenesis to activation of endogenous virus particles, and also the correlation between Adl2 carcinogenesis and cancer related genes. Acta Pathol Jpn 42: 242-248, 1992.  相似文献   
90.
Cationic polymerization of styrene in the presence of 1-(p-methoxybenzyl)tetrahydrothiophenium hexafluoroantimonate ( 3 ) as an efficient cationic initiator was investigated. 3 was synthesized in an excellent yield by the reaction of p-methoxybenzyl bromide with tetrahydrothiophene and the subsequent exchange of bromide ions for hexafluoroantimonate ions. In the polymerization of styrene, 3 acted as a potent thermally latent initiator which initiates the polymerization at a slightly higher temperature than room temperature, although no polymerization occurs at room temperature for 30 min. 3 is a much more active initiator than the previously reported benzylsulfonium salt 1 . The enhanced activity of 3 was also confirmed in the polymerization of glycidylb phenyl ether.  相似文献   
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