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991.
Ping Xu Shuichi Hashimoto Hiroyuki Miyazaki Koushi Asabe Sachiko Shiraishi K. Sueishi 《Virchows Archiv : an international journal of pathology》1998,432(1):17-25
Morphometric analyses of the immunohistochemical expression of the Clara cell secretory 10-kDa protein (CC10) and surfactant
apoproteins A and B (SP-A and -B) were carried out on the developing bronchi and bronchioles of human fetuses and neonates.
We analysed the ratio of the number of CC10-positive cells per subepithelial length of the bronchial or bronchiolar basement
membrane and found that both the bronchial and the bronchiolar population of CC10-positive cells was significantly higher
than that of either SP-A or SP-B. In addition, CC10 was found to be distributed mainly in the bronchiole. CC10-positive cells
began to be recognized in the late pseudoglandular phase (15 weeks of gestation) and thereafter gradually increased in the
canalicular and terminal sac phases, which correspond to the active development period of the acini or peripheral airways.
The earliest expression of SP-A was also noted at 15 weeks of gestation, but its positive epithelial cells were present mainly
in the larger bronchi. Double immunohistochemical staining for CC10 and SP-A revealed that the CC10-positive cells lining
both the bronchi and bronchioles were different from the SP-A-positive cells. This finding suggests that CC10-positive cells
are functionally and developmentally heterogeneous in both fetal and neonatal lungs in humans
Received: 22 May 1997 / Accepted: 21 July 1997 相似文献
992.
993.
Role of glutathione metabolism of Treponema denticola in bacterial growth and virulence expression 下载免费PDF全文
Hydrogen sulfide (H(2)S) is a major metabolic end product detected in deep periodontal pockets that is produced by resident periodontopathic microbiota associated with the progression of periodontitis. Treponema denticola, a member of the subgingival biofilm at disease sites, produces cystalysin, an enzyme that catabolizes cysteine, releasing H(2)S. The metabolic pathway leading to H(2)S formation in periodontal pockets has not been determined. We used a variety of thiol compounds as substrates for T. denticola to produce H(2)S. Our results indicate that glutathione, a readily available thiol source in periodontal pockets, is a suitable substrate for H(2)S production by this microorganism. In addition to H(2)S, glutamate, glycine, ammonia, and pyruvate were metabolic end products of metabolism of glutathione. Cysteinyl glycine (Cys-Gly) was also catabolized by the bacteria, yielding glycine, H(2)S, ammonia, and pyruvate. However, purified cystalysin could not catalyze glutathione and Cys-Gly degradation in vitro. Moreover, the enzymatic activity(ies) in T. denticola responsible for glutathione breakdown was inactivated by trypsin or proteinase K, by heating (56 degrees C) and freezing (-20 degrees C), by sonication, and by exposure to N alpha-p-tosyl-L-lysine chloromethyl ketone (TLCK). These treatments had no effect on degradation of cysteine by the purified enzyme. In this study we delineated an enzymatic pathway for glutathione metabolism in the oral spirochete T. denticola; our results suggest that glutathione metabolism plays a role in bacterial nutrition and potential virulence expression. 相似文献
994.
脑电(Electroencephalography, EEG)和功能磁共振(Functional magnetic resonance imaging, fMRI)技术的结合,可以实现两者优势的互补,获得更加合理的源定位结果.本文报道的是一种将fMRI先验信息结合到脑电源定位中的新方法.在该方法中,先利用SPM方法计算获得fMRI的统计映射参数,然后将基于计算获得的统计参数构造的权矩阵结合到FOCUSS的迭代过程中,对脑电的反演提供具有fMRI先验空间位置信息的约束,提高脑电的源空间定位精度,从而获得更加合理的定位结果.通过对一形状知觉实验fMRI和脑电数据的结合定位分析,结果初步证实了改进方法能获得和生理更加一致的结果. 相似文献
995.
An immunohistochemical study of neuronal and glial cell reactions in retinae of rats with experimental glaucoma 总被引:5,自引:0,他引:5
Wang X Tay SS Ng YK 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2000,132(4):476-484
Glaucoma is a common disease seen in the eye clinic, but its associated pathological processes, especially the role of glial cells in glaucomatous retinae, are still under debate. The aim of the present work was to study the responses of astrocytes, Müller cells and microglia in retinae of rats with experimental glaucoma. Glaucoma was induced in adult male Wistar rats by cauterizing limbal-derived veins and the changes in glial fibrillary acidic protein (GFAP), OX42, OX18, OX6 and EDI expression were studied by immunohistochemical staining. Neuronal cell viability was studied by immunostaining with the neuronal nuclei (NeuN) antibody. In the experimental glaucomatous eyes, a significant drop in the number of NeuN-positive neurons was observed from 7 days postoperation and beyond in both the ganglion cell layer and inner nuclear layer. The expression of GFAP and OX42 was increased during the first 2 months after operation and reduced in rats at 3 and 4 months. OX6 and OX18 immunoreactivity was induced in some microglia of both glaucomatous and sham-operated control eyes. Possible mechanisms of the reaction of astrocytes, Müller cells and microglia in neuronal degeneration following glaucoma are discussed. 相似文献
996.
Contribution of the twin arginine translocation system to the virulence of enterohemorrhagic Escherichia coli O157:H7 总被引:3,自引:0,他引:3 下载免费PDF全文
Shiga toxin-producing Escherichia coli O157:H7 is a major food-borne infectious pathogen. In order to analyze the contribution of the twin arginine translocation (TAT) system to the virulence of E. coli O157:H7, we deleted the tatABC genes of the O157:H7 EDL933 reference strain. The mutant displayed attenuated toxicity on Vero cells and completely lost motility on soft agar plates. Further analyses revealed that the ΔtatABC mutation impaired the secretion of the Shiga toxin 1 (Stx1) and abolished the synthesis of H7 flagellin, which are two major known virulence factors of enterohemorrhagic E. coli O157:H7. Expression of the EDL933 stxAB1 genes in E. coli K-12 conferred verotoxicity on this nonpathogenic strain. Remarkably, cytotoxicity assay and immunoblot analysis showed, for the first time, an accumulation of the holotoxin complex in the periplasm of the wild-type strain and that a much smaller amount of StxA1 and reduced verotoxicity were detected in the ΔtatC mutant cells. Together, these results establish that the TAT system of E. coli O157:H7 is an important virulence determinant of this enterohemorrhagic pathogen. 相似文献
997.
Development of hatching blastocysts from immature human oocytes following in-vitro maturation and fertilization using a co-culture system 总被引:8,自引:0,他引:8
Hwu YM; Lee RK; Chen CP; Su JT; Chen YW; Lin SP 《Human reproduction (Oxford, England)》1998,13(7):1916-1921
Recently, in-vitro maturation (IVM) of immature human oocytes recovered
from non-stimulated follicles has been applied in the treatment of
infertility. However, in previous reports, very few embryos cultured in
conventional medium have reached the expanded blastocyst stage following
in-vitro maturation and fertilization (IVM/IVF). The objective of this
study was to investigate whether the developmental competence of human
embryos following IVM/IVF could be enhanced by the use of a human ampullary
cell co-culture system. Immature human oocytes were aspirated from small
follicles at Caesarean section and then cultured in medium containing human
menopausal gonadotrophin for 36 to 48 h, followed by insemination. Zygotes
were randomly cultured either in conventional culture medium alone or in
the co-culture system. Of 48 embryos cultured in conventional medium alone,
all arrested at the 2-16- cell stage on day 3 after insemination. Of 46
embryos cultured in the co-culture system, 26 embryos (56.5%) arrested at
the 2-16-cell stage. Six embryos (13%) developed to the morula stage.
Fourteen embryos (30.4%) developed to expanded blastocysts and two
blastocysts were hatching on day 7 after insemination. We conclude that
co-culture significantly enhances the development of blastocysts in embryos
resulting from IVM/IVF.
相似文献
998.
Si Jin Zhu Yin Chang Xu Ming Cao Li Min He Wei Liang You Sheng Guan Xiao Hong 《Clinical and Vaccine Immunology : CVI》2005,12(1):198-201
A dipstick dye immunoassay (DDIA) was developed to detect immunoglobulin G (IgG) or IgM antibodies of toxoplasmosis infection in humans. The assays employ a blue colloidal dye particles (D-1) conjugated to sheep anti-human IgG and rabbit anti-human IgM as the visualizing agents and a soluble antigen of tachyzoites of Toxoplasma gondii strain RH (TSA) as the detective antigen. The mixture of dye-labeled anti-human antibody-special human antibody was captured by TSA onto a nitrocellulose membrane dipstick by means of immunochromatography. The assays are rapid (the whole test can be completed within 15 min), simple, and cheap, and they don't require any equipment. They are sensitive and specific for the detection of anti-Toxoplasma IgG or IgM antibodies and generally agree closely with the results from the enzyme-linked immunosorbent assay. The assays are especially suitable for field applications. 相似文献
999.
Jiang X Gao X Zheng H Yan M Liang W Shao Z Li W Zhang E Hu Y Hai R Yu D Kan B Xu J 《Clinical and diagnostic laboratory immunology》2004,11(6):1182-1184
Specific immunoglobulin G antibody for severe acute respiratory syndrome (SARS) coronavirus was detected in maternal blood, umbilical blood, and amniotic fluid from a pregnant SARS patient. Potential protection of fetus from infection was suggested. 相似文献
1000.
精神分裂症恢复期患者及家属家庭干预的对照研究 总被引:3,自引:1,他引:3
目的:以康复期出院精神分裂症患者和家属为对象,定期复诊进行家庭干预并对照研究。方法:干预组68例,对照组52例,采用BPRS评定;干预组家属74人,对照组家属65人,采用SCL-90评定。结果:6个月后干预组患者BPRS和入组时对照比较均有显著性差异(P<0.01),说明干预组患者的精神症状,不良情绪及社会功能明显好转,入组时两组家属SCL-90评定与常模对照比较,均有明显差异(P<0.05或0.01),经干预后干预组与全国常规比较无显著性差异(P>0.05),说明患者家属普遍存在心理障碍,经干预后家属心理状况明显改善。结论:对康复期病人及家属进行门诊家庭干预,是有效的康复方法,值得推广应用。 相似文献