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991.
It has been suggested that plasmacytoid monocytes (PMOs) play an essential role in T-cell-dependent immune response. Indeed, numerous PMOs are found in close topographical association with epithelioid cell granulomas in hypersensitivity-type granulomas, such as tuberculosis and sarcoidosis. The key pathologic process in cat scratch disease (CSD) usually involves a B-cell-associated granulomatous reaction. Histologically, CSD appears to exhibit a histopathologic diversity, including suppurative lesions without epithelioid cell granulomas (early lesion), in which the microabscesses were surrounded by monocytoid B-cells (MBCs), suppurative granulomas containing MBCs (intermediate lesion), and suppurative granulomas without MBCs (late lesion). However, the presence or absence of PMO in CSD has not been studied previously. We examined 14 cases of CSD. In early lesions, numerous clusters of PMO were detected in the MBCs. In intermediate lesions, both MBCs and PMOs were found to be decreased in number, while late lesions contained no or only a few MBCs and PMOs. Overall, these findings suggest that PMOs may play a role in MBC-associated granulomatous response and in hypersensitivity granulomatous response. Moreover, the association with MBCs and PMOs indicates a functional relationship of MBCs with PMOs in the formation of suppurative lesions in CSD.  相似文献   
992.
OBJECTIVE: We sought to evaluate the long-term efficacy and safety of epalrestat, an aldose reductase inhibitor, on diabetic peripheral neuropathy. RESEARCH DESIGN AND METHODS: Subjects with diabetic neuropathy, median motor nerve conduction velocity (MNCV) >or=40 m/s, and HbA(1c) 相似文献   
993.
High mobility group box 1 (HMGB1) is a non-histone protein involved in maintaining the architecture of chromatin. HMGB1 also acts extracellularly as a cytokine, in processes such as inflammation, cell migration and stem cell recruitment. The involvement of HMGB1 in granulocyte colony-stimulating factor (G-CSF)-induced mobilisation of haematopoietic stem cells was investigated in 21 healthy donors. G-CSF treatment significantly elevated serum HMGB1 levels, which increased from 1.16 +/- 0.86 ng/ml, before treatment, to 31.1 +/- 5.99 ng/ml, after treatment. These findings suggest HMGB1 may play a role during the mobilisation of stem cells from the bone marrow into the systemic circulation.  相似文献   
994.
The beneficial effects of quinidine on ST-segment elevation, inducible ventricular tachyarrhythmias, and episodes of ventricular tachyarrhythmia have been reported in Brugada syndrome. This is the first report describing quinidine-induced elimination of the late potential, which is considered one of the parameters for an arrhythmic event, in a patient with Brugada syndrome.  相似文献   
995.
We compared pharmacologically-perturbed hemodynamic parameters (cerebral blood volume; CBV, and flow; CBF) by acetazolamide administration in six healthy human subjects studied with positron emission tomography (PET) and near-infrared (NIR) time-resolved spectroscopy (TRS) simultaneously to investigate whether NIR-TRS could measure in vivo hemodynamics in the brain tissue quantitatively. Simultaneously with the PET measurements, TRS measurements were performed at the forehead with four different optode spacing from 2 cm to 5 cm. Total hemoglobin and oxygen saturation (SO2) measured by TRS significantly increased after administration of acetazolamide at any optode spacing in all subjects. In PET study, CBV and CBF were estimated in the following three volumes of interest (VOIs) determined on magnetic resonance images, VOI1: scalp and skull, VOI2: gray matter region, VOI3: gray and white matter regions. Acetazolamide treatment elevated CBF and CBV significantly in VOI2 and VOI3 but VOI1. TRS-derived CBV was more strongly correlated with PET-derived counterpart in VOI2 and VOI3 when the optode spacing was above 4 cm, although optical signal from cerebral tissue could be caught with any optode spacing. As to increase of the CBV, 4 cm of optode spacing correlated best with VOI2. To support the result of TRS-PET experiment, we also estimated the contribution ratios of intracerebral tissue to observed absorption change based on diffusion theory. The contribution ratios at 4 cm were estimated as follows: 761 nm: 50%, 791 nm: 72%, 836 nm: 70%. These results demonstrated that NIR-TRS with 4 cm of optode spacing could measure cerebral hemodynamic responses optimally and quantitatively.  相似文献   
996.
Proteinase/antiproteinase imbalance is a widely accepted theory for the pathogenesis of COPD. Among various proteinases, matrix metalloproteinases (MMPs) digest extracellular matrix of the lung and play significant roles in the development of COPD. Polymorphisms of an MMP that upregulate its activity may result in the degradation of the lung matrix. A case-control study was performed to investigate the association of polymorphisms of the MMP14 gene with COPD. Japanese subjects (96 COPD patients and 61 controls) and Egyptian subjects (106 COPD patients and 72 controls) were recruited. Each subject was genotyped for seven single nucleotide polymorphisms (SNPs) of the MMP14 gene; -165 G/T and -72 G/A in the promoter region, +221 C/T in exon 1, +6727 C/G and +6767 G/A in exon 5, +7096 T/C in exon 6, and +8153 G/A in exon 8. The distributions of the genotype frequencies of these SNPs were not significantly different between the COPD patients and the controls in either ethnic group after correction of multiple comparisons. In the haplotype analysis, however, the haplotype -165 T : +221 T : +6727 C : +7096 C had a significantly higher frequency in the Egyptian COPD group than the control group (pcorr = 0.0063). The haplotype of the MMP14 gene, -165 T : +221 T : +6727 C : +7096 C, might be involved in the pathogenesis of COPD.  相似文献   
997.
998.
Platelet aggregation measured by the optical density method has been applied for the assessment of platelet functions. However, as the method has to use platelet-rich plasma, it requires centrifugation of blood samples, which takes a considerable period of time. Using whole blood as samples has advantage because there is no pre-treatment of samples before measurement of platelet functions. Additionally, it would be desirable to have a bedside assay that reflects hyper-function of platelets and can monitor inhibitory effects of anti-platelet drugs. Rapid Platelet Function Assay (RPFA) is a qualitative test to aid the detection of platelet dysfunction due to anti-platelet drug ingestion, which uses citrated whole blood for sample in point of care or laboratory settings. The RPFA is a turbidimetric analysis, based on an optical detection system which measures platelet agglutination as an increase in light transmission. The aim of this study is to assess the accuracy and reproducibility of RPFA and to determine whether RPFA can monitor the effects of anti-platelet drugs. During the first 30 minutes after blood collection, Aspirin Reaction Units (ARU) determined with RPFA gradually increased, and reached its plateau after 30 minutes. The ARU values remained almost constant thereafter until 6 hours after blood collection (Fig. 3). These findings suggest that platelet function is unstable immediately after blood collection. Therefore, in this study ARU measurement was performed 60 minutes after blood collection. The reproducibility of ARU is very good both before and after aspirin intake. Seven days after daily uptake aspirin, ARU was decreased as compared with the control (440.8 +/- 39.4 vs. 663.4 +/- 2.4 ARU). RPFA measurement provides rapid information on platelet function that mirrors turbidimetric platelet agglutination and reflects COX1-depedent platelet activity.  相似文献   
999.
Chronic stimulus subsequent to cell injury plays an important role in cancer development, but the precise mechanisms remain unknown partly because appropriate animal models are lacking. In the present study, the effects of hepatotoxicant carbon tetrachloride (CCl(4)) on in vivo mutagenicity were investigated using gpt delta mice with or without p53. Female B6C3F(1) p53-proficient or -deficient gpt delta mice were given a diet containing 300 ppm of 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) for 13 weeks, concurrently with intraperitoneal injection of 1 ml/kg CCl(4) solution once a week. Mutant frequencies of gpt and red/gam in p53-proficient mice fed MeIQx were both significantly elevated by CCl(4)co-treatment. Enhancing effects of CCl(4) treatment were also noted in p53-deficient mice. In the mutation spectra analysis of gpt mutant colonies, G:C to T:A transversions were predominantly observed regardless of CCl(4) injection, and clonal expansion of gpt colonies were increased in the co-treated group as compared with MeIQx alone group. The present data showing no significant changes in mRNA expression levels of CYP1A2 and GSTa4 between MeIQx-treated groups with and without CCl(4). In the Western blotting analysis, CYP1A2 protein levels were significantly decreased in the co-treated group as compared to MeIQx alone group, and GSTα protein levels were not changed among any groups. It is suggested that the mutant frequency by co-treatment with CCl(4) might result from some factors other than p53 or MeIQx metabolism/excretion. Thus, our data clearly demonstrate that this model could be a powerful tool for identifying the mechanisms underlying combinatorial effects on carcinogenesis.  相似文献   
1000.
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