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161.
To examine the role of the Fas ligand/Fas (FasL/Fas) system and apoptosis in renal allograft rejection, we analyzed FasL/Fas expression and apoptosis in 63 renal allograft biopsy specimens obtained from 56 renal transplant recipients in Tokyo, Japan. Sixteen biopsy specimens were diagnosed (Banff criteria) as acute rejection (AR), 17 as AR plus chronic rejection, 10 as borderline stages, and 20 as no rejection (NR). Immunohistochemically, Fas antigen was highly expressed in the renal tubular epithelium in tissues from patients with rejection. The mean number of Fas-positive tubular epithelium was significantly higher in biopsy specimens with AR than in those with NR, but FasL expression was highly expressed in infiltrating lymphocytes in the interstitium of allografts with cellular rejection. The mean number of FasL-positive infiltrating lymphocytes was significantly higher in specimens with AR than in those with NR or borderline stages. For detection of apoptotic cells, the specimens were subjected to terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling, which showed that the mean number of tubular epithelial cells positive for this labeling was highest for the specimens with AR, the number being significantly higher than in those with AR plus chronic rejection or with NR. Thus, Fas expression on epithelial cells might actively trigger their apoptosis by the interaction between Fas and FasL. Studies of human normal renal-derived cell lines (RPTEC 2601 [epithelial] and NHMC 5155 [mesangial]) showed that both constitutively expressed Fas (but not FasL) mRNA. After pretreatment with interferon-gamma, Fas-induced apoptosis was observed in the RPTEC 2601 line, but without interferon-gamma pretreatment, anti-Fas-mediated apoptosis was not seen. Under identical conditions, the NHMC 5155 line was resistant to anti-Fas-mediated apoptosis regardless of interferon-gamma pretreatment. This suggested that AR might be associated with increased apoptosis in the renal tubular epithelial cells mediated by the Fas/FasL system.  相似文献   
162.
An autopsy case of Sj?gren-Larsson syndrome (SLS), an 8-year-old boy, is presented with neuropathological investigations. Widespread deposition of 2 different types of unusual substances, stained lightly or strongly with periodic acid Schiff (PAS) was most conspicuous in this case. The first type of them, lightly stained with PAS at room temperature, was widely distributed in the central nervous system (CNS): the white matter of cerebrum and brainstem, subpial and subependymal glial layers, subpial space, perivascular space of small blood vessels, and their adjacent nervous tissue. The second type, strongly stained with PAS, small round or ellipsoid bodies, was found in the subpial, subependymal and perivascular glial layers. The first type of PAS-positive substances might be fatty alcohols or their metabolites, and the second type, some degraded products of lipids in astrocytic processes. Lipofuscin-like substances were accumulated in perivascular macrophages located around small blood vessels. Spheroid bodies (axonal swellings) were frequently observed in relay nuclei: lateral geniculate body (LGB), pontine nuclei, inferior olivary nuclei, posterior funicular nuclei, or cerebellar dentate nuclei. A lot of PAS-positive fine granules were contained in a spheroid body of LGB. Scarcity of myelinated nerve fibers was recognized in the cerebral and cerebellar white matter and the corticospinal tracts of spinal cord. Focal cortical dysgenesis, resembling that of unlayered polymicrogyria, was observed in bilateral insular cortices. Further histochemical studies are needed to explore the exact pathogenesis, but widespread deposition of PAS-positive substances in CNS may support the supposition that SLS is one of congenital errors of lipid metabolism.  相似文献   
163.
A 3 dB gain-reduction bandwidth up to 65 nm (1549-1614 nm) is achieved using a two-stage erbium-doped fibre amplifier, together with an intermediate equaliser and Raman amplification in the transmission fibre  相似文献   
164.
A novel subset of peripheral T cells, peripheral NK T cells, is found to be a major population comprising 5% of splenic T and 40% of bone marrow T cells. The majority of peripheral NK T cells are characterized by the expression of an invariant TCR-alpha encoded by V alpha 14/J alpha 281 with a one nucleotide N region. Moreover, a specific reduction of V alpha 14+ NK T cells has been demonstrated to be tightly associated with various autoimmune diseases, indicating their decisive role in autoimmune disease development. In this study, we investigated the phenotypes of peripheral V alpha 14+ NK T cells and their TCR-beta repertoire. Peripheral V alpha 14+ NK T cells, comprise two populations, i.e., small and large sized cells, at an equal frequency, belonged to the CD4- CD8- fraction, and are heat stable antigen(bright), macrophage-1bright, B220bright, CD45RBdim, and Mel-14dim, but CD5-, distinct from thymic NK T cells. TCR-beta analysis clearly showed that peripheral V alpha 14+ NK T cells utilized two to three dominant invariant TCR-beta, such as V beta 8.2 D beta J beta 2.5/V beta 7 D beta J beta 2.1 in the spleen and liver, V beta 8.2 D beta J beta 2.5/V beta 8.3 D beta J beta 2.2/V beta 7 D beta J beta 2.6 in the bone marrow, and V beta 7 D beta J beta 2.1/V beta 3 D beta J beta 1.2 in intestinal intraepithelial lymphocytes. Judging from the unusual surface phenotypes, such as heat stable antigen, macrophage-1, B220, CD45RBdim, and Mel-14dim, which are known to be T cell activation markers, peripheral V alpha 14+ NK T cells may always be activated under physiologic conditions, resulting in the oligoclonal expansion of V alpha 14+ NK T cells with different invariant TCR-beta in different peripheral organs. The unique features of V alpha 14+ NK T cells are discussed.  相似文献   
165.
The general pharmacological properties of a novel cholecystokinin-A antagonist, loxiglumide ((+/-)-4-(3,4-dichlorobenzamido)-N-(3-methoxypropyl)-N-pentylgl utaramic acid, CR 1505, CAS 107097-80-3) on central nervous system, autonomic nervous system, cardio-respiratory system, gastrointestinal system, hematological and miscellaneous systems were investigated in experimental animals. 1. Central nervous system: At a dose of 30 mg/kg, i.v. loxiglumide showed ptosis in one of 6 mice, but at doses of 3 and 10 mg/kg, i.v. no change on gross behavior in mice. Loxiglumide had no effect on locomotor activity and thiopental-induced hypnosis, anti-convulsive activity, analgesic activity in mice and rectal temperature changes in rats. 2. Autonomic nervous system: In vitro, loxiglumide at concentrations of 10(-4) and 3 x 10(-4) mol/l slightly inhibited agonist-induced contractions in the isolated guinea pig ileum and spontaneous rhythmic contractions in the isolated non-pregnant rat uterus. But loxiglumide had no effect on oxytocin-induced contraction in isolated non-pregnant rat uterus. 3. Cardio-respiratory system: Loxiglumide had no effect on heart rate and electrocardiogram in anesthetized dogs. But it slightly increased blood pressure and decreased the frequency of respirations at a dose of 30 mg/kg, i.v. Furthermore, loxiglumide slightly decreased femoral arterial blood flow at doses of more than 3 mg/kg, i.v. On the other hand, it had no effect on contractile force or contraction rate in the isolated guinea pig atrium and resting tension in the isolated rabbit aorta. 4. Gastrointestinal system: Loxiglumide increased bile secretion at doses of 10 and 30 mg/kg, i.v. in anesthetized rats and at doses of 3, 10 and 30 mg/kg, i.v. in anesthetized dogs. However, total bile acid output was not affected by loxiglumide. On the other hand, loxiglumide had no effect on pancreatic secretion, gastric secretion and gastric emptying in rats and intestinal transport activity in mice. 5. Hematology: In vitro, in the case of samples without bovine serum albumin, at concentrations of more than 1.9 x 10(-3) mol/l loxiglumide showed hemolysis, while in the case of samples with bovine serum albumin, at concentrations of more than 6.9 x 10(-3) mol/l loxiglumide showed hemolysis, and its maximal potency was weak compared to albumin-free conditions. On the other hand, in vivo, loxiglumide had no effect on hemolysis. In addition, it had no effect on platelet aggregation, prothrombin time and activated partial thromboplastin time. 6. Miscellaneous pharmacological actions: Loxiglumide had no effect on local anesthetic activity in guinea pigs and renal function in mice. These results suggest that loxiglumide seems to produce no serious side effects on the central nervous system, autonomic nervous system, cardio-respiratory system, gastrointestinal system, hematological and miscellaneous systems at pharmacologically effective doses.  相似文献   
166.
Monogalactosyldiacylglycerol (MGDG) synthase (UDPgalactose:1,2-diacylglycerol 3-beta-D-galactosyltransferase; EC 2.4.1.46) catalyzes formation of MGDG, a major structural lipid of chloroplast. We cloned a cDNA for the synthase from cucumber cDNA library. The full-length cDNA clone was 2142 bp, and it contains a 1575-bp open reading frame encoding 525 aa. The open reading frame consists of the regions for a mature protein (422 aa; Mr of 46,552) and transit peptide to chloroplast (103 aa). Although the molecular weight of mature protein region matched that purified from cucumber cotyledons, it was quite different from those purified from spinach (approximately 20 kDa) reported by other groups. The mature region of the protein was expressed in Escherichia coli as a fusion protein with glutathione S-transferase. The expression in E. coli showed that the protein catalyzed MGDG synthesis very efficiently. Therefore, we concluded that the cDNA encodes MGDG synthase in cucumber. In addition, the deduced amino acid sequence of the MGDG synthase cDNA showed homology with MurG of Bacillus subtilis and E. coli, which encode a glycosyltransferase catalyzing the last step of peptidoglycan synthesis in bacteria. This sequence homology implies that the machinery of chloroplast membrane biosynthesis is evolutionarily derived from that of cell wall biosynthesis in bacteria. This is consistent with the endosymbiotic hypothesis of chloroplast formation.  相似文献   
167.
The precise mechanism of fever and flu-like syndrome that occurs in treatment with deoxycytidine analogues remains unclear. This study demonstrated a strong correlation between plasma interleukin 6 levels and fever in treatment with oral (E)-2'-deoxy-2'(fluoromethylene)cytidine, another deoxycytidine analogue.  相似文献   
168.
Exfoliative toxins of approximately 30 kDa produced by Staphylococcus hyicus strains NCTC 10350, 1289D-88 and 842A-88 were purified and specific polyclonal antisera were raised against each of the toxins. It was shown by immunoblot analysis and ELISA that three exfoliative toxins from S. hyicus were antigenically distinct. The three toxins were designated ExhA, ExhB and ExhC. From 60 diseased pigs, each representing an outbreak of exudative epidermitis, a total of 584 isolates of S. hyicus were phage typed and tested for production of exfoliative toxin. ExhA-, ExhB- and ExhC-producing S. hyicus isolates were found in 12 (20%), 20 (33%) and 11 (18%), respectively, of the 60 pig herds investigated. Production of the different types of exfoliative toxin was predominantly associated with certain phage groups. However, toxin production was found in all of the six phage groups defined by the phage typing system. Some changes in the distribution of isolates between phage groups were observed when the results of this study were compared to previous investigations. In this study two new antigenically distinct exfoliative toxins were isolated and tools for in vitro detection of toxin producing S. hyicus isolates and for further studies on the exfoliative toxins from S. hyicus have been provided.  相似文献   
169.
Derived narrow-band auditory brain-stem responses (ABRs) in young normal-hearing subjects revealed a significant gender difference in response time between frequency regions of the cochlea. Females showed shorter delays than males between derived bands. This differential has not been previously reported. As in many early studies, the unmasked amplitude of the wave V complex was significantly larger (30%) in females than males. However, differences in amplitudes of the narrow-band responses were too small to account for the differential in the unmasked response. It is hypothesized that the larger amplitude of the unmasked wave V complex in females occurs because of a faster response time across the cochlea leading to better neural synchrony and, therefore, larger amplitudes. Furthermore, results can be explained by assuming that the stiffness gradient in the cochlea is 13% larger in females than in males. If males and females have the same cochlear tonotopic mapping, the female cochlea should be 13% shorter. This prediction is highly consistent with recent anatomical studies of cochlear length and gender. The results of the present study indicated possibly important cochlear mechanisms that influence the main parameters of ABRs. An understanding of these cochlear mechanisms may improve the diagnostic capabilities of ABRs in patients with peripheral hearing loss.  相似文献   
170.
Report of an infant with aplasia of the proximal part of the fibula on both sides; by our knowledge the second observation in the literature. Furthermore the infant shows an aplasia of the thyroidea, a coarctation of the aorta, an atrial septal defect and an intraperitoneally situated ascending as well as descending colon.  相似文献   
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