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21.
Despite the huge number of colonized Gram-negative bacteria in the colon, the normal colon maintains its homeostasis without any excessive immune response. To investigate the potential mechanisms involved, human colonic lamina propria mononuclear cells (LPMCs) obtained from uninflamed mucosa were cultured with lipopolysaccharide (LPS) prepared from Bacteroides vulgatus (BV-LPS) or Bacteroides fragilis (BF-LPS), as representatives of indigenous flora, or pathogenic Salmonella minnesota (SM-LPS). Colonic LPMCs failed to produce inflammatory cytokines in response to any type of LPS. Colonic macrophages barely expressed mRNA for MD-2, an essential association molecule for LPS signaling via Toll-like receptor 4. Further, BV-LPS induced CD25 and Foxp3 expression in lymphocytes and CD4(+)CD25(+) cells expressed IL-10 mRNA. Thus, the low expression of functioning LPS receptor molecules and induction of IL-10-producing CD4(+)CD25(+) lymphocytes by indigenous LPS may play a central role in the maintenance of colonic immunological homeostasis.  相似文献   
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A new commercial rapid 10-min one-step immunochromatography (IC) test, SAS RSV test, was compared to another IC test, Directigen EZ RSV, employing RT-PCR as the "gold standard" for detecting respiratory syncytial virus. Of 102 clinical samples, 79 were positive by RT-PCR, 66 (82.5%) were positive with the SAS RSV test, and 55 (69.6%) were positive with Directigen EZ RSV. The specificity of the new test was 91.3% (21 of 23), similar to that of Directigen EZ RSV (100% [23 of 23]). This test performs well enough to be used for patient care.  相似文献   
24.
An anticarbamazepine antibody was detected in the serum of a patient with severe carbamazepine-induced serum sickness. We found that the patient's T cells and IgG antibody recognized an epitope which appeared in subjects showing an allergic reaction, as well as that in subjects who showed no allergic reaction, after long-term carbamazepine therapy. These results show that an anti-carbamazepine immune response does not occur in the majority of subjects who undergo long-term carbamazepine therapy without developing allergic symptoms, although the immunodominant haptenic epitope of carbamazepine is present in their sera.  相似文献   
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A simple and rapid method for the determination of macrophage activating factor is described. A new type of apparatus suitable for the measurement of macrophage chemiluminescence was devised, and the effect of lymphokines on macrophage activities was studied by measuring phorbol myristate acetate-induced luminol-dependent chemiluminescence. An outstanding feature of the new apparatus is that the plastic dish used for the cell culture can be used as the vessel for the chemiluminescence reaction. When thioglycollate-elicited ICR mouse peritoneal macrophages were incubated with lymphokines, their ability to generate chemiluminescence increased rapidly, reaching a maximal level at about 4 h, and then it progressively decreased to the control level at 8 h. Although this increasing effect of lymphokines on macrophage chemiluminescence was short-lived, it could be seen at a relatively low concentration, at which lymphokine-mediated cytotoxic activity of macrophages was not observed.  相似文献   
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A new type of chemiluminescence (CL) was observed in thioglycolate-elicited ICR mouse peritoneal macrophages which had been incubated for 24 h in medium containing lymphokines (LK) and lipopolysaccharides (LPS), and then exposed to a CL reagent solution containing luminol and phorbol myristate acetate (PMA). The new CL, which was clearly distinguishable from PMA-induced CL, appeared immediately after the addition of the CL reagent solution, reaching a maximal level at about 30 s, and disappeared rapidly. We have called the new CL 'spontaneous CL', since it appeared spontaneously without PMA triggering. When the macrophages were incubated with LK in the presence of 10 ng/ml of LPS, the spontaneous CL began to appear after about 4 h incubation, the maximal level being reached at about 12 h, after which it decreased gradually on further incubation. After 48 h, it could not be observed at all. The spontaneous CL could be observed only in macrophages simultaneously treated with LK and LPS, as in the case of cytotoxicity. The correlation between spontaneous CL and cytotoxicity was suggested by the following; they showed a similar dose dependency to LK, and neither of them could be induced in aged macrophages which had been incubated in vitro for 1 day before exposure to LK and LPS. These results suggest that spontaneous CL measurement could possibly replace the cytotoxicity test as a simple method for the determination of macrophage activating factor.  相似文献   
29.
Monomers containing several octadecyl groups, e.g., 2-isopropenyl-4,6-bis(octadecylamino)-1,3,5-triazine ( 2 ), 2-dioctadecylamino-4-isopropenyl-6-octadecylamino-1,3,5-triazine ( 3 ) and 2,4-bis(dioctadecylamino)-6-isopropenly-1,3,5-triazine ( 4 ) were prepared by the alkylation reaction of 2,4-diamino-6-isopropenyl-1,3,5-triazine ( 1 ) with 1-bromooctadecane in the presence of sodium hydride. In the free-radical homopolymerization of these monomers, the polymer yield of 3 was lower than that of 2 due to a decrease in the ceiling temperature, and the polymerization of 4 did not proceed. Copolymerizations of these monomers with styrene or methyl methacrylate were carried out and the monomer reactivity ratios (r1 and r2) were determined. The monomer reactivity decreased with increasing the number of octadecyl groups in the monomers. Crystallinity of the octadecyl side chains in the resulting comb-like polymers was evaluated by differential scanning calorimetry.  相似文献   
30.
The androgens testosterone and dihydrotestosterone (DHT) are essential for a variety of systemic functions in mature males. Alteration of these hormones results in late-onset hypogonadism (LOH) and benign prostate hyperplasia (BPH). The fruit bodies of fungi of the genus Cordyceps have been regarded as folk medicine or health food with tonic and antifatigue effects. The extract from the fruit body of Cordyceps militaris parasitizing Samia cynthia ricini (CM) was evaluated as a novel-candidate natural product for ameliorating male andropause symptoms. To explore the effects of CM on LOH and BPH, CM was applied to rat models and cultured testicular cells and prostate cells. The concentrations of androgens in the serum and culture media were determined by ELISA. Expression of steroidogenic enzymes and androgen-related genes was evaluated by qPCR, and prostatic cell proliferation was assessed with the cell-viability assay. CM maintained the serum levels of testosterone and DHT, but inhibited testosterone-induced prostate hypertrophy. CM also increased the secretion of testosterone and DHT by primary testicular cells, with no changes in the mRNA expression of steroidogenic enzymes, but decreased the growth of prostatic cell lines. Our data suggest that CM could improve both LOH and BPH in males.  相似文献   
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