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1.
We have found that steroid bolus withdrawal prior to graft reperfusion increased the incidence of acute cellular rejection (ACR). This study aims to clarify how initial steroid bolus (ISB) injection at reperfusion influences the kinetics of CD8(+) alloreactive immune responses immediately after living donor liver transplantation (LDLT). A total of 49 hepatitis C virus (HCV)-infected recipients were classified into 3 groups according to hierarchical clustering by preoperative CD8(+)CD45 isoforms. The naive T cell proportion was considerably higher in Group I than in Groups II and III, whereas Group II recipients had the highest effector memory (EM) T cells and Group III the highest effector T cells. The frequency of ACR was significantly higher in recipients without ISB than in those with ISB. In particular, the ACR rates were the highest in Group II without ISB. Following ISB, the proportion of effector T cells was promptly upregulated within 6 hours after graft reperfusion, simultaneously with the upregulation of CD27(-)CD28(-) subsets, interferon-gamma (IFN-gamma), tumor necrosis factor-alpha and perforin expression, which significantly correlated with increasing interleukin (IL)-12 receptor beta 1 cells. These were then downregulated to below preoperative levels by tacrolimus (Tac) administered at 24 hours. These changes did not occur in the absence of ISB. In Group II without ISB, the downregulation of IL-12Rbeta1(+) cells was the greatest, consistent with the highest rates of ACR and mortality (60%). In conclusion, ISB must be done in place, especially in Group II with preexisting high EM T cells, to enable the development of early allograft acceptance.  相似文献   
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The healing effect of human epidermal growth factor (hEGF) on open wounds was studied in rats. No improvement in wound healing was found by topical application of EGF alone to open wound sites. We found an ointment containing EGF and a protease inhibitor, nafamostat mesilate or gabexate mesilate, or gelatin accelerated the healing rate of open wounds. Significant increases in the dry weight of the wound site granulation tissue, uronic acid (as an index of acid mucopolysaccharide) and hydroxyproline (as an index of collagen) were observed by treatment with EGF ointment containing nafamostat compared with the controls. The effects of the protease inhibitor on wound healing were dose dependent. Nafamostat was more efficient than gabexate or gelatin on wound healing. The degradation of 125I-EGF in wound tissue homogenate was significantly decreased in the presence of a protease inhibitor, such as nafamostat or gabexate, or gelatin. These findings indicate that the stabilization of EGF at the wound site is an important factor in permitting the expression of its healing effects and suggest that the ointment containing EGF and a stabilizing agent would be a suitable dosage form for acceleration of wound repair.  相似文献   
4.
The diastereoisomeric glucuronic acid conjugates of R/S-benoxaprofen are the major benoxaprofen metabolites and are found in urine at high concentrations. The conjugates of R- and S-benoxaprofen can be separated directly on a C18 reversed-phase column using a mixture of acetonitrile and tetrabutylammonium hydroxide buffer, pH 2.5 (28:72, v/v), as the mobile phase. The k values of S- and R-benoxaprofen glucuronides are 57.5 and 63.0, respectively. Diluted urine or deproteinized plasma samples were injected without further treatment. With fluorescence detection at 313/365 nm, quantifiable limits of 50 ng equiv./ml were found for the conjugates. The intra- and interday variability was below 12%. Utilizing this analytical procedure it is possible to characterize enantioselective glucuronidation both in vivo and in vitro. For in vitro procedures, apparent rates of formation and the R/S ratio may be substrate (benoxaprofen) and cosubstrate (UDPGA) dependent. Moreover, enantioselective cleavage of the formed benoxaprofen glucuronides by alkaline hydrolysis, hydrolytic enzymes, and acyl migration must be controlled for both in vitro and in vivo studies since R-benoxaprofen glucuronide is degraded faster than the S-diastereomer under certain conditions.  相似文献   
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An epicutaneous application of 2,4-dinitrofluorobenzene (DNFB) to a mouse ear caused a transient skin swelling, and the repetition of the challenge enlarged the contact dermatitis. The repeated challenge with DNFB also induced eosinophil infiltration on the application site. Administration of a chymase inhibitor significantly inhibited the ear swelling as well as eosinophil accumulation. An intradermal injection of human chymase to the mouse ear also elicited transient skin swelling and eosinophil infiltration, both of which were augmented in proportion to the number of injections. Human serum albumin and heat-inactivated chymase failed to induce such skin reactions, suggesting the participation of proteolytic activity of the enzyme. In addition, chymase stimulated eosinophil migration in vitro in a concentration-dependent manner. Taken together, these observations suggest that mast cell chymase may contribute to development of the DNFB-induced dermatitis, probably by promoting eosinophil infiltration. It is therefore possible that chymase plays a role in pathogenesis of chronic dermatitis such as atopic dermatitis.  相似文献   
7.
The gold standard diagnostic method for sleep apnea syndrome(SAS) is overnight polysomnography(PSG), but is costly in terms of time and money. We studied the usefulness of a 24-hour ambulatory respirometer equipped with oximeter(Hotmate) for screening of SAS. Seventy-six cases of suspected SAS were enrolled(68 males and 8 females, mean age 51). The correlation between data from Hotmate and PSG was evaluated in 24 cases who underwent both of the tests for the final diagnosis of SAS. There was a good correlation between the two parameters of the data obtained by Hotmate(H) (H-apnea index(AI) vs H-desaturation index(DI)). Among 24 cases who underwent both Hotmate and PSG, there was a good correlation between the data from PSG and Hotmate(PSG-AI vs H-AI: r = 0.80, p < 0.001). Both sensitivity and specificity were highest when screening criteria of H-DI > 15 was utilized(sensitivity = 91.7%, specificity = 66.7%). Our findings suggest that the respiromonitor with oximeter is useful for the screening the patients with SAS.  相似文献   
8.
The physicochemical properties of mitochondria in liver tissue obtained from rats given 32% ethanol, 32% propanol or 6.9% butanol in drinking water for up to 3 months were investigated using differential scanning calo-rimetry and fluorescence polarization measurements. The results obtained were as follows: 1) Phospholipids extracted from mitochondria showed increases in the relative amounts of phosphatidylcholine, phosphatidylinositol and phosphatidylserine, and a decrease in the relative amount of phosphatidylethanolamine. An increase in the unsatu-rated/saturated fatty acid ratio of phospholipids was also observed. 2) Elevation of the thermotropic lipid phase transition temperature with a decrease in the enthalpy value (δ H ) was revealed by differential scanning calo-rimetry. 3) The elevation of the lipid phase transition temperature was detected also by fluorescence polarization measurements using 1,6 diphenyl 1, 3, 5 hexatriene (DPH) as a probe. Elevation of mitochondrial membrane fluidity was found in some of the experimental animals, but most showed no changes in comparison with the control. A possible role of membrane fusion in the mechanism of formation of ethanol-, propanol- and butanol induced hepatic megamitochondria is discussed on the basis of these results. Acta Pathol Jpn 42: 549–557, 1992.  相似文献   
9.
We studied the pheno- and genotypes of an oral Granulicatella elegans strain in comparison with those of a blood-derived isolate which caused infective endocarditis. The two isolates exhibited identical biochemical characteristics and had the same drug MICs. Their genotypes were indistinguishable, indicating that these were from the same clone. The transmission of G. elegans from the oral cavity thus should be noted as a possible cause of infective endocarditis.  相似文献   
10.
Nine healthy male volunteers (mean age of 24) participated in two experimental sessions of random crossover design: a bright light (5000 lux for 5 h from 00:00 to 05:00 h) session and a dim light (10 lux for 5 h from 00:00 to 05:00 h) session. Subsequently participants entered an ultra-short sleep-wake schedule for 26 h, in which a sleep-wake cycle consisting of 10-min sleep EEG recording on a bed and 20-min resting awake on a semi-upright chair were repeated. Saliva melatonin level and core body temperature was measured throughout the experiment. Bright light significantly delayed rhythms of melatonin secretion (01:58 h), core body temperature (01:12 h) and sleep propensity (02:00 h), compared as dim light session. Significant positive correlation was found between bright light-induced phase change in core body temperature and that in sleep propensity rhythm. Light-induced melatonin suppression significantly positively correlated with the phase change in core body temperature and that in sleep propensity rhythm. Assuming that light-induced melatonin suppression represents an acute impact of light on the circadian pacemaker, our results suggest that such an impact may be directly reflected in phase changes of sleep propensity and core body temperature rhythms rather than in melatonin rhythm.  相似文献   
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