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991.
Goldfish Carassius auratus were acclimated to either 10 or 30°C for a minimum of 5 weeks. A 65-kDa protein specific to warm-temperature-acclimated fish was extracted from the gel with 70% formic acid after two-dimensional electrophoresis of the muscle cytoplasmic protein fraction. The 65-kDa protein thus prepared to homogeneity was used to raise specific antibodies in rabbit by conventional methods. The antibody produced exhibited specific reaction with a protein having the same molecular weight from brain and liver tissue, suggesting that the 65-kDa protein is a ubiquitous cytosolic component in warm-acclimated goldfish. When water temperature was increased from 20 to 30°C over a 20-h period, a prominent amount of the 65-kDa protein was observed in muscle tissue extracts within 5 days of additional rearing; this was demonstrated by immunoblotting with the specific antibody. The N-terminal amino acid sequence of the 65-kDa protein was determined as Asp-Glu-Pro-Gln-Gly-His-Gln-His (or Asp)-Glu-Leu, differing from that of a family of known heat-shock proteins having about 70 kDa in molecular mass (hsp 70). No interaction between ATP and the 65-kDa protein revealed by ATP-agarose affinity chromatography further confirmed the different properties of the 65-kDa protein from those of hsp 70.Abbreviations ATP adenosine 5-triphosphate - hsp heat-shock protein(s) - IgG immunoglobulin G - mRNA messenger ribonucleic acid - PMSF phenylmethylsulphonyl fluoride - PVDF polyvinylidene difluoride - SDS sodium dodecyl sulphate - SDS-PAGE SDS-polyacrylamide gel electrophoresis  相似文献   
992.
The laminated structure of the optic tectum is formed by radial and tangential cell migration during development. Studies of developing chick optic tectum have revealed two streams of tangential cell migration in the middle and superficial layers, which have distinctive origins, migratory paths, modes of migration, and destinations. We will review the process of the two types of tangential migrations, in order to elucidate their roles in the formation of the optic tectum layers.  相似文献   
993.
During our studies on toxic substances from clinically isolated Nocarida, a new isolate identified as Nocardia otitidiscaviarum from cutaneous nocardiosis was found to produce a toxic substance called HS-6 that had strong in vitro as well as in vivo toxicity. The mouse intraperitoneal LD50 value was 1.25 mg/kg and the ED50 value for L1210 cultured cells was 0.3 ng/ml. The structure of HS-6 was determined and found to belong to the 16-membered macrocyclic group with a molecular formula of C43H68O12. HS-6 also showed activity against pathogenic fungi such as Cryptococcus neoformans.  相似文献   
994.
Contrapsin and two isoforms, F (fast) and S (slow), of alpha-1-antiproteinase (also called alpha-1-proteinase inhibitor) were isolated in an apparently homogeneous state from plasma of inflamed guinea pigs. Contrapsin inactivated trypsin, but did not significantly affect chymotrypsin, pancreatic elastase, or pancreatic kallikrein. On the other hand, both isoforms of alpha-1-antiproteinase inhibited trypsin, chymotrypsin, and elastase, but not plasma or pancreatic kallikrein. The S isoform of alpha-1-antiproteinase was present in barely detectable amounts in healthy animals, but increased markedly when the acute-phase reaction was induced by subcutaneous injection of turpentine. On the other hand, the plasma levels of the F isoform, contrapsin, and alpha-macroglobulin showed moderate (1.5 to 2.3-fold) elevation during the acute-phase reaction. In contrast to the previous findings that rats and rabbits contain two different alpha-macroglobulins, one of which is an acute-phase reactant while the other is not, inflamed guinea pigs contained only one species of alpha-macroglobulin. Murinoglobulin, the most prominent acute-phase negative protein in both mice and rats, showed no significant change in guinea pigs. These results indicate that guinea pig plasma contains four major trypsin inhibitors, i.e., contrapsin, alpha-1-antiproteinase, alpha-macroglobulin, and murinoglobulin, the properties of which are very similar to those of the respective mouse homologues, but that the acute-phase response of these inhibitors differs greatly from that of the homologous proteins in rats or mice.  相似文献   
995.
Recent reports suggest the hepatic iron concentration (HIC) may influence the activity of hepatitis and the response to interferon (IFN) therapy in patients with chronic hepatitis C (CH-C). We have evaluated iron status in 28 patients with CH-C and determined if pretreatment iron status can predict the response to IFN-α therapy in these patients. Increased serum iron, transferrin saturation, and ferritin levels were observed in 3 (11%), 11 (39%), and 5 (18%) patients, respectively. Hepatic iron deposits were histologically detected in 17 (61%) patients, and 14 of them had stainable hepatocytic iron. However, all HIC values were within the normal range (203–1279 μg/g). Seven of 17 patients treated with IFN-α for 6 mo had normalization of serum transaminases and disappearance of serum HCV-RNA (responders). Nonresponders had a significantly higher median HIC compared with responders (710 vs 343 μg/g, respectively;p < 0.05). There was no significant difference in other pretreatment iron parameters, serum HCV-RNA level, or HCV-genotype between responders and nonresponders. In conclusion, mild hepatic iron accumulation occurs in patients with CH-C. Increased hepatic iron stores are associated with poor response to IFN therapy. Pretreatment HIC may be an additional host-specific parameter with a predictive value for responsiveness to IFN therapy, in addition to well-known predictive viral factors.  相似文献   
996.
The antitumor effect of paclitaxel, epirubicin, and both in combination was tested using R-27, an estrogen receptor-positive human breast carcinoma. In anin vivo study using nude mice both drugs showed an additive effect, whereas they showed a supraadditive pattern inin vitro MTT assay. The combination of paclitaxel and epirubicin may enhance the antitumor effect on breast carcinoma.  相似文献   
997.
Toxins convertthe hepatocellular response to tumor necrosis factor- (TNF-)stimulation from proliferation to cell death, suggesting thathepatotoxins somehow sensitize hepatocytes to TNF- toxicity. Becausenuclear factor-B (NF-B) activation confers resistance to TNF-cytotoxicity in nonhepatic cells, the possibility that toxin-inducedsensitization to TNF- killing results from inhibition ofNF-B-dependent gene expression was examined in the RALA rathepatocyte cell line sensitized to TNF- cytotoxicity by actinomycinD (ActD). ActD did not affect TNF--induced hepatocyte NF-Bactivation but decreased NF-B-dependent gene expression. Expressionof an IB superrepressor rendered RALA hepatocytes sensitive toTNF--induced apoptosis in the absence of ActD. Apoptosis was blockedby caspase inhibitors, and TNF- treatment led to activation ofcaspase-2, caspase-3, and caspase-8 only when NF-B activation wasblocked. Although apoptosis was blocked by the NF-B-dependent factornitric oxide (NO), inhibition of endogenous NO production did notsensitize cells to TNF--induced cytotoxicity. Thus NF-Bactivation is the critical intracellular signal that determines whetherTNF- stimulates hepatocyte proliferation or apoptosis. Althoughexogenous NO blocks RALA hepatocyte TNF- cytotoxicity, endogenousproduction of NO is not the mechanism by which NF-B activationinhibits this death pathway.

  相似文献   
998.
We microanalyzed 2,3-dinor-6-keto-prostaglandin F (2,3-dinor-6-keto-PGF 1) and 11-dehydrothromboxane B2 (11-dehydro-TXB2, 2) in human urine. Samples containing a [2H4]-analogue as an internal standard were extracted by chromatography using Sep Pak tC18 and silica gel. The compounds were then analysed by means of the lactone ring opening reaction and dimethylisopropylsilylation. The conversion of 1 to 1-methyl ester (ME)-propylamide (PA)-9,12,15-dimethylisopropylsilyl (DMIPS) ether derivative and of 2 to 1-ME-6-methoxime (MO)-9,12,15-tris-DMIPS ether derivative was followed by gas chromatography/selected ion monitoring (GC/SIM). Interfering substances from the urine matrix were eliminated during GC/SIM analysis using a DB-5 column. We were able to detect 1 (222–1031 pg/mg creatinine) and 2 (18–155 pg/mg creatinine) in human urine. Furthermore, the thromboxane/prostacyclin (IX/PGI) ratio in the urine of diabetics was higher than that of healthy volunteers. This method can be used to determine the TX/PGI balance in human urine.  相似文献   
999.
To test the hypothesis that CD8+ T cells may suppress the allergen-induced late airway response (LAR) and airway eosinophilia, we examined the effect of administration of Ag-primed CD8+ T cells on allergic airway responses, bronchoalveolar lavage (BAL) leukocytes, and mRNA expression for cytokines (IL-4, IL-5, and IFN-gamma) in OVA-sensitized Brown Norway rats. On day 12 postsensitization to OVA, test rats were administered 2 million CD8+ T cells i.p. isolated from either the cervical lymph nodes (LN group; n = 8) or the spleen (Spl group; n = 6) of sensitized donors. On day 14, test rats were challenged with aerosolized OVA. Control rats were administered PBS i.p. on day 12, and challenged with OVA (n = 10) or BSA (n = 6) on day 14. The lung resistance was measured for 8 h after challenge. BAL was performed at 8 h. Cytospin slides of BAL were analyzed for major basic protein by immunostaining and for cytokine mRNA by in situ hybridization. The LAR was significantly less in the LN group (1.8 +/- 0.5 U; p < 0.01) and BSA controls (1.4 +/- 0.7; p < 0.01), but not in the Spl group (6.7 +/- 2.2), compared with that in OVA controls (8.1 +/- 1.8). In BAL, the number of major basic protein-positive cells was lower in the LN and Spl groups compared with OVA controls (p < 0.05 and p < 0.01). IL-4- and IL-5-positive cells were decreased in the LN group compared with the OVA controls (p < 0.01). INF-gamma-positive cells were increased in the LN and Spl groups compared with the OVA controls (p < 0.01). Serum OVA-specific IgE levels were unaffected by CD8+ T cell transfers. These results indicate that Ag-primed CD8+ T cells have a potent suppressive effect on LAR.  相似文献   
1000.
The existence and distribution of mammosomatotrophs (MS cells) containing growth hormone (GH) and prolactin (PRL) in bovine adenohypophysis were detailed by a combined method of mirror sections and immunohistochemical staining. MS cells always occurred in bovine adenohypophysis but their number was low. In the midsagittal plane, the cells were observed in the hind dorsal, hind ventral and fore ventral region abundant in GH and PRL cells. Whereas, in the zona tuberalis where GH and PRL cells were less frequent, MS cells were not detected. MS cells were invariably solitarily distributed within mammotroph (PRL cell) clusters but not within somatotroph (GH cell) clusters. The proportion of MS cells declined as the ages proceeded and the appearance was spatially related to the arrangement of PRL cells. These findings indicated that, in bovine adenohypophysis, MS cells were differentially distributed and occurred in PRL cell clusters. The results strongly suggest that MS cells originate in GH cells pre-existed within PRL cell clusters with special reference to the functional activation of PRL cells.  相似文献   
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