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81.
 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   
82.
The intraerythrocytic stage of the simian malaria parasite Plasmodium coatneyi (CDC strain) was intravenously inoculated into two species of macaques with different susceptibilities to infection with this parasite, including four Japanese macaques (Macaca fuscata) and three cynomolgus macaques (M. fascicularis). The Japanese macaques infected with P. coatneyi developed severe clinical manifestations similar to those of severe human malaria and eventually became moribund, while the infected cynomolgus macaques, natural hosts of the parasite, exhibited no severe manifestation of disease except anemia and finally recovered from the infection. In the infected Japanese macaques, peripheral CD4(+) and CD8(+) T-cell populations were markedly decreased and fragmentation of chromosomal DNA in peripheral blood mononuclear cells was detected during the terminal period of infection, suggesting that apoptotic cell death was responsible at least in part for the T lymphocytopenia. Furthermore, soluble Fas ligand levels in sera of the infected Japanese macaques increased gradually to a markedly high level of 28. 83 +/- 10.56 pg/ml (n = 4) when the animals became moribund. On the other hand, none of the infected cynomolgus monkeys exhibited either T lymphocytopenia or elevated soluble Fas ligand level. These findings suggest that differences in immune response between the two species of macaque tested accounted for the contrasting outcomes after infection with the same isolate of malarial parasite, and in particular that a profound T lymphocytopenia due to Fas-derived apoptosis played a role in the fatal course of malaria in the infected Japanese macaques.  相似文献   
83.
Molecular size and charge distribution of IgA of sera and glomerular eluates were investigated in ddY mice, spontaneously developing mesangial proliferative glomerulonephritis (GN) with IgA deposition after 40 weeks of age. Serum IgA levels were increased in aged ddY mice more than 40 weeks old with a significant increase (P less than 0.01) at the age of 60 weeks, comparing with those of BALB/c mice. The isoelectric focusing (IEF) spectrotype of pooled serum IgA in 60-week-old mice ranged from 4.2 to 5.5, being similar to those in younger ddY (16 weeks old) and control BALB/c mice (12 weeks old) without enhanced expression of specific IgA peaks. However, IgA in the glomerular eluate from the 60-week-old mice showed limited anionic spectrotypes from pH 4.2 to 4.8. HPLC of IgA in pooled sera and glomerular eluates of 16-, 40- and 60-week-old ddY mice, revealed markedly increased ratios of the dimeric IgA (dIgA) and polymeric IgA (pIgA) in the total IgA with age. In the contrast to serum profiles, monomeric IgA (mIgA) was always detected as the smallest peak of the IgA fractions in glomerular eluates. Furthermore, aged mice with severe GN showed a higher percentage of dIgA and pIgA in total IgA (80%) in the sera than that of the mice with mild GN (64%). HPLC analysis under acid condition of glomerular IgA from 40-week-old ddY mice showed a similar pattern of dIgA and pIgA peaks in neutral buffer without the appearance of mIgA. These findings suggest that there is a selective mechanism for glomerular accumulation of more acid IgA among the polyclonally expanded IgA in old ddY mice, and that the polymeric form of IgA plays a pathogenic role in the development of mesangial proliferative GN in these mice.  相似文献   
84.
The tissue differentiation of the zona glomerulosa of the fetal adrenal cortex of rats was studied by giving experimental treatments to the fetus in vivo. A low-glucocorticoid-condition was given to the fetus by bilateral adrenalectomy of pregnant rats for removing exogenous glucocorticoids from the fetus, and by brain aspiration of the fetuses for removing the fetal pituitary gland (ACTH) and endogenous glucocorticoids. When the fetus was placed under a low-glucocorticoid-condition for the last couple of days of gestation, poor differentiation of the zona glomerulosa occurred speciflcally in the fetal adrenal cortex. The degree of the poor differentiation seemed to be proportional to the duration of the low-glucocorticoid-condition. Supplemental administration of glucocorticoids could prevent this poor differentiation of the zona glomerulosa. These results indicate that the tissue differentiation of the zona glomerulosa of the fetal adrenal cortex depends much on glucocorticoids.  相似文献   
85.
We assessed the occurrence of atypical adenomatous hyperplasia (AAH) in whole lung lobes with primary cancer lesions. Following surgical resection, tissue specimens were sliced to a thickness of 4 mm (3,641 specimens from 61 cases; mean = 59.7 specimens per case). A total of 119 AAH foci were found and an association was evident in 25 (57%) of 44 adenocarcinomas, 3 (30%) of 10 squamous cell carcinomas, and 2 (29%) of 7 other lung cancers. Histologic evaluation showed that 108 AAH foci were categorized as low-grade and the other 11 as high-grade AAH. These 11 foci of high-grade AAH were present in 7 patients with adenocarcinoma, and in 1 patient there was a synchronous double primary lung adenocarcinoma. High-grade AAH was closely associated with bronchioloalveolar carcinoma (BAC) type adenocarcinoma, and low-grade AAH with non-BAC adenocarcinoma. The mean +/- SD Ki-67 labeling index in high-grade AAH (3.5%+/-2.9%) was significantly higher than for the low-grade index (1.4%+/-1.6%). We propose that foci of high- but not low-grade AAH may be potential precursor lesions of lung adenocarcinoma, especially with the BAC component.  相似文献   
86.
alpha-N-(3-Acyloxyacyl)-ornithine (or -serine) is the structure of lipoamino acids obtained by us previously from some gram-negative bacteria (Y. Kawai and I. Yano, Eur. J. Biochem. 136:531-538, 1983; Y. Kawai, I. Yano, and K. Kaneda, Eur. J. Biochem. 171:73-80, 1988; Y. Kawai, I. Yano, K. Kaneda, and E. Yabuuchi, Eur. J. Biochem. 175:633-641, 1988). The 3-acyloxyacylamide structure is present in both the lipoamino acids and lipid A of lipopolysaccharide (endotoxin). The efficacy of lipoamino acids (an ornithine-containing lipid and a serine-containing lipid) in activating C3H/HeSlc mouse peritoneal exudate macrophages was compared with that of bacterial lipopolysaccharide, because the two types of substances were expected to exhibit similar biological activities and physiological functions on the basis of their structural similarities. Actually, the lipoamino acids, as well as lipopolysaccharide, strongly activated the macrophages to generate the immunoregulatory substances prostaglandin E2 and interleukin-1, but their effect on the induction of L929 cell cytolytic factor (a possible tumor necrosis factor), another immunoregulatory substance, was weaker than that of lipopolysaccharide. The effect of lipoamino acids on the cytotoxicity of macrophages for EL-4 leukemia cells was very weak. However, all of these activities, as far as tested, were strongly enhanced by synergistic action with gamma interferon. Only the serine-containing lipid killed both C3H/HeSlc and C3H/HeJ macrophages to almost the same degree as endotoxin killed C3H/HeSlc macrophages. On the other hand, lethal toxicity for mice was not found with either the ornithine-containing lipid or the serine-containing lipid, even when 7 mg of compound was injected into a mouse. These studies suggest that the lipoamino acids are nontoxic characteristic immunoactivators.  相似文献   
87.
A cDNA of the glycoprotein (G protein) gene of rabies virus Nishigahara strain was cloned and inserted into a baculovirus genome under the control of the polyhedrin promoter. Infection of Spodoptera frugiperda cells with this recombinant virus produced a large quantity of new protein instead of the parental polyhedrin protein. By immunofluorescent and immunoblotting analyses, the recombinant protein was antigenically similar to the authentic G protein. Its molecular mass estimated by sodium dodecyl sulfate polyacrylamide gel electrophoresis, however, was slightly smaller than that of the authentic one, and this observation was suggested to be due to the difference in glycosylation level between the two G proteins. The recombinant G protein expressed on the cell surface of the insect cells showed a fusion activity at low pH. The fusion activity was inhibited by antiserum against either whole virions or G protein of rabies virus.  相似文献   
88.
Invasive fungal infection (IFI) is a significant complication after allogeneic hematopoietic stem cell transplantation (HSCT); however, we have little information on its clinical features after reduced intensity cord blood transplantation (RICBT) for adults. We reviewed medical records of 128 patients who underwent RICBT at Toranomon Hospital between March 2002 and November 2005. Most of the patients received purine-analogbased preparative regimens. Graft-versus-host disease (GVHD) prophylaxis was a continuous infusion of either tacrolimus 0.03 mg/kg or cyclosporine 3 mg/kg. IFI was diagnosed according to the established EORTC/NIH-MSG criteria. IFI was diagnosed in 14 patients. Thirteen of the 14 had probable invasive pulmonary aspergillosis and the other had fungemia resulting from Trichosporon spp. Median onset of IFI was day 20 (range: 1-82), and no patients developed IFI after day 100. Three-year cumulative incidence of IA was 10.2%. Four of the 13 patients with invasive aspergillosis (IA) developed grade II-IV acute GVHD, and their IA was diagnosed before the onset of acute GVHD. The mortality rate of IFI was 86%. Multivariate analysis revealed that the use of prednisolone >0.2 mg/kg (relative risk 7.97, 95% confidence interval 2.24-28.4, P = .0014) was a significant risk factor for IA. This study suggests that IFI is an important cause of deaths after RICBT, and effective strategies are warranted to prevent IFI.  相似文献   
89.
Y Matsumoto  K Kawai  Y Tomita    M Fujiwara 《Immunology》1990,69(2):215-221
Susceptibility to experimental autoimmune encephalomyelitis (EAE), which is an autoimmune disease inducible by immunization with a brain-specific antigen in complete Freund's adjuvant (CFA), is different among strains. In an attempt to resolve the immune mechanisms by which the difference in susceptibility to EAE is regulated, we re-estimated susceptibility of several strains of rats, and the frequency of antigen-reactive T cells in each strain was determined by limiting-dilution analysis. EAE was induced in Lewis (LEW), PVG/c and BN rats using four different methods: (i) active immunization with guinea-pig myelin basic protein (GPBP) in CFA; (ii) immunization with GPBP in CFA that had been further supplemented with Mycobacterium tuberculosis H37Ra (supplemented CFA); (iii) adoptive transfer of GPBP-activated spleen cells into syngeneic rats; and (iv) transfer of a GPBP-specific T-cell line. The LEW strain was susceptible to all four methods. The PVG/c strain was resistant to immunization with GPBP in conventional CFA (GPBP/conv. CFA), but was susceptible to immunization with GPBP in supplemented CFA (GPBP/suppl. CFA) and to transfer of activated spleen cells. The BN strain was resistant to all methods. Limiting-dilution analysis using T cells from LEW, PVG/c or BN rats has revealed that each strain of rat displays a different pattern of frequencies of GPBP-reactive or the 68-88 sequence (GP68-88)-reactive T cells. LEW rats showed relatively high frequencies of GPBP-reactive and GP68-88-reactive T cells after immunization with either GPBP/conv. CFA or GPBP/suppl. CFA, symptomatic rats showing higher values than asymptomatic rats. In asymptomatic PVG/c rats, the frequency of GP68-88-reactive T cells was lower than that of GPBP-reactive T cells. In PVG/c rats with clinical EAE, however, GP68-88-reactive T cells increased in frequency and were almost the same as GPBP-reactive T cells. BN rats, on the other hand, responded very poorly not only to the GP68-88 sequence but also to the whole GPBP molecule, even after immunization with GPBP/suppl. CFA. These findings, obtained by limiting-dilution analysis, strongly suggest that the development of EAE in LEW, PVG/c and BN rats is closely related to the frequency of GPBP-reactive T cells. Furthermore, it is shown that resistance to EAE found in PVG/c and BN rats may be generated by different immune mechanisms.  相似文献   
90.
In order to clarify the role of fibronectin in glioma invasion in vivo, we analyzed the relationship between fibronectin-stimulated cell migration and adhesion in 14 primary glioma cells and the expression of fibronectin and the fibronectin receptor in the corresponding tumor tissues. The tumors comprised nine glioblastomas (GB) and five anaplastic gliomas (AG) consisting of two astrocytomas, two oligoastrocytomas and one ependymoma. All glioma cells tested in the primary cell culture were found to migrate to fibronectin in a dose-dependent manner. The extent of cell migration to fibronectin was not significantly different for the GB and AG groups. On the other hand, cell adhesion to fibronectin in the AG was much stronger than that in the GB group. Immunohistochemistry demonstrated that fibronectin positively stained in the extra-cellular matrix (ECM) in eight cases and that the fibronectin receptor was positive in tumor cell membranes in 10 cases. In addition, cellular fibronectin isoforms containing ED-A and ED-B sequences were found to be immunolocalized in the tumor cells and the ECM of GB. These isoforms were also specifically expressed in tumor vessels within tumor tissues, but not in those within normal brain tissues. Cell migration tended to be expressed more strongly by glioma cells derived from tumor tissues in which fibronectin was posi-tively immunolocalized in the ECM than from tissues with negative fibronectin in the ECM. Four glioma cells derived from GB whose tumor cells did not positively stain for fibronectin receptors migrated much less extensively to fibronectin than other glioma cells whose tissues showed positive staining for the fibronectin receptor. Of these four GB, two had loss of heterozygosity in the locus of fibronectin receptor b1 gene. These results suggest that fibronectin deposited in the extracellular matrix of tumors, which can be derived from both plasma and the tumor cell itself, strongly promotes the migration of glioma cells, and that expression of the fibronectin receptor may play a critical role in the biological behavior of the tumor cells, particularly in fibronectin-stimulated cell migration in vivo.© Kluwer Academic Publishers 1998  相似文献   
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