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61.
The lipophilic yeast Malassezia is an exacerbating factor in atopic dermatitis (AD) and colonizes the skin surface of patients with AD. With the goal of reducing the number of Malassezia cells, we investigated the antifungal activities of a therapeutic agent for AD, tacrolimus, and the azole agents itraconazole and ketoconazole against Malassezia species in vitro. We examined 125 strains of the 11 currently accepted Malassezia species by using the agar dilution method. All strains of the 11 Malassezia species were very susceptible to both azole agents, with MICs ranging from 0.016 to 0.25 mug/ml. Tacrolimus had antifungal activities against half of the strains, with MICs ranging from 16 to 32 mug/ml. Two of the major cutaneous floras, Malassezia globosa and Malassezia restricta, have several genotypes in the intergenic spacer region of the rRNA gene; the azole agents had slightly higher MICs for specific genotype strains of both microorganisms. A combination of azole agents and tacrolimus had a synergistic effect against Malassezia isolates, based on a fractional inhibitory index of 0.245 to 0.378. Our results provide the basis for testing these agents in future clinical trials to reduce the number of Malassezia cells colonizing the skin surface in patients with AD.  相似文献   
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The interaction of cephalosporin antibiotics with renal cortex of rats has been examined in vitro by means of cortical slice uptake and binding assay to plasma membranes and other subcellular fractions, including the comparative study with p-aminohippurate. The uptakes of cephalexin and cephaloridine by cortical slices were concentrative, and were strongly inhibited in the presence of 2, 4-dinitrophenol, ouabain, nitrogen gas and probenecid. In the case of cefazolin, the degree of concentrative uptake and influence of inhibitors were low. Cephalexin, cephaloridine and p-aminohippurate specifically bound to the basolateral membranes, compared to brush border membranes and other subcellular fractions. Cefazolin binding to basolateral membranes was relatively small. These results suggest that the specificity of cephalexin and cephaloridine bindings to the basolateral membranes could be related to the interaction with the organic acid transport system at the antiluminal side. Thus, an examination of cephalosporin interaction with plasma membranes from renal cortex could offer an appropriate in vitro model system to study the renal transport of these antibiotics.  相似文献   
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BACKGROUND: Bunashimeji-related hypersensitivity pneumonitis is found among workers who cultivate the mushroom in indoor facilities. An evaluation of protective measures was initiated using the outcomes of clinical, immunological, and radiological findings. METHODS: Twenty-two patients presented with symptoms of HP; all were employed cultivating Bunashimeji mushrooms in indoor facilities. After hospitalization, 6 of 22 patients quit their job to avoid exposure to spores (Avoidance group). Sixteen patients continued to work used a mask for 3 months, and were then divided into two subgroups: Mask alone (seven patients) and mask plus oral prednisolone (Mask + PSL) (nine patients). The erythrocyte sedimentation rate (ESR), serum Krebs von der Lungen-6 (KL-6), surfactant protein-D (SP-D), lymphocyte stimulation test (LST), ground-glass scores in chest high-resolution computed tomography (HRCT), and bronchoalveolar lavage (BAL) were assessed before and after treatment. RESULTS: Complete avoidance resulted in a significant decrease in LST. There was a significant decrease after PSL treatment in serum KL-6, SP-D, and total cell counts in the BAL fluid in the Mask + PSL group. In the Mask alone group, serum KL-6, SP-D, ground-glass scores in chest HRCT and total cell counts in BAL fluid showed high levels compared with the other two groups. CONCLUSIONS: Complete cessation was the best treatment for hypersensitivity pneumonitis. The use of a mask was ineffective for patients with a high serum KL-6 and SP-D concentration and severe ground-glass opacity on chest HRCT. Initial treatment with PSL is recommended for these patients with high levels of total cell counts in BAL fluid.  相似文献   
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This study investigated the changes in nitric oxide (NO) together with inducible nitric oxide synthase (iNOS) content and enzyme activity at 0, 4, 12, 24, and 48 h following acute muscle stretch injury. A single stretch injury was induced to the tibialis anterior muscle of 30 male New Zealand white rabbits (n = 6 at each time point). Injured and uninjured contralateral sham-operated muscles were harvested and analyzed for NO levels, iNOS content, and iNOS activity at each time point. Furthermore, three animals were used to estimate baseline NO levels and iNOS activity. There was a progressive reduction in NO content in the injured and the sham-operated muscles up to 24 h postoperation and stretch injury (p < 0.05). At 48 h postinjury, however, NO levels were 146% higher in injured muscles than in sham-operated muscles (p < 0.05). iNOS protein content was higher at 4 h and 48 h in injured versus shamoperated muscles (p < 0.05). Similarly, iNOS activity was higher at 4 h (p < 0.05) and at 48 h (p < 0.01) in injured versus sham-operated muscles. These results suggest that NO may play an active role during the postinjury recovery of skeletal muscle modulated by iNOS expression.  相似文献   
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1. The role of shear stress in nitric oxide (NO)-mediated attenuation of anaphylactic venoconstriction was studied using an isolated ovalbumin-sensitized guinea pig liver. 2. Guinea pigs were actively sensitized by a subcutaneous injection of 1 mg ovalbumin. Two weeks after sensitization, the livers were perfused with diluted blood under constant flow or constant perfusion pressure. The constant flow could result in increased shear stress during constriction, while the constant perfusion pressure could prevent changes in shear stress. Using the double occlusion technique to estimate the hepatic sinusoidal pressure, pre- and postsinusoidal constriction was evaluated. Hepatic anaphylaxis was induced by an injection of ovalbumin (4 microg) into the perfusate, the volume of which was 40 mL. 3. Under either constant flow or pressure, anaphylaxis caused venoconstriction of predominantly presinusoids over postsinusoids, although anaphylactic venoconstriction under constant pressure was significantly greater than that under constant flow. When shear stress was held constant by maintaining constant perfusion pressure, a NO synthase inhibitor, Nomega-nitro-L-arginine methyl ester (L-NAME, 100 micromol/L), potentiated similarly both pre- and postsinusoidal constriction induced by anaphylaxis. This suggests that hepatic anaphylaxis shear stress-independently generates NO, resulting in dilatation of both pre- and postsinusoidal vessels in a similar magnitude. In contrast, when shear stress was allowed to rise under constant flow, anaphylactic presinusoidal constriction was preferentially potentiated by L-NAME. 4. Hepatic anaphylaxis can increase NO production in a shear stress-independent manner and dilates similarly both pre- and postsinusoids, while NO produced in a shear stress-dependent manner attenuates predominantly venoconstriction of the presinusoids where shear stress is preferentially increased.  相似文献   
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Absorption enhancers, which increase the permeability of drugs through epithelial membranes without damaging them, are especially useful for intranasal administration of peptide drugs. In this study, aminated gelatins, candidate enhancers, having different numbers of amino groups were prepared from gelatin (H-gelatin, isoelectric point = 9.0, MW 100 kDa) and a partial gelatin hydrolysate (L-gelatin, isoelectric point = 8.0, MW 5 kDa), and the enhancing effects on the nasal absorption of insulin, used as a model peptide drug, and 5(6)-carboxyfluorescein (CF), a paracellular marker, were examined in rats. The enhancing effect on insulin and CF depends on the MW and number of amino groups. A high correlation between the enhancing effects on insulin and CF was observed and this suggests that an increase in the paracellular permeability is the mechanism governing the nasal absorption-enhancement of aminated gelatins, at least as far as insulin and CF are concerned. The enhancing mechanism might be shared with other cationic polymers having absorption-enhancing effects.  相似文献   
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