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31.
We have established two rat mAbs, TUGH4 and TUGh5, specificfor the human chain of the IL-2 receptor (IL-2R), which isknown to be shared among receptors for IL-2, IL-4 and IL-7.The antibodies bound to cell lines transfected with the human chain gene but not to their parental cell lines, and precipitated65–70 and 80–90 kDa cell surface molecules fromlysates of human T cells surface-labeled with Na125I and chemicallycross-linked with [125]IL-2 respectively. Flow cytometry withTUGh4 and TUGh5 detected the chain in a wide variety of peripheralblood cell populations including CD4+ T cells, CD20+ T cells,CD20+ B cells, CD56+ natural killer cells, CD4+ monocytes andgranulocytes, contrasting with expression of the and ßchains of IL-2R.  相似文献   
32.
OBJECTIVE: To investigate the mechanism of staurosporine-induced glioma cell death and cell cycle arrest using adenovirus-mediated gene transfection, as well as the function of retinoblastoma (Rb) and genetic instability induced by staurosporine. METHODS: Cell cycle regulation, cell death and nuclear abnormalities induced by staurosporine were examined using an adenovirus vector expressing Rb, p16 or p21 genes in human glioma cell lines. RESULTS: The Rb-defective SF-539 cell line was resistant to staurosporine compared with cell lines expressing intact Rb. SF-539 glioma cells exposed to staurosporine became multinucleated and then died. Multinucleation was prevented in SF-539 cells transfected with the Rb gene, thus decreasing the death rate of these cells. CONCLUSIONS: These results imply that enforced Rb expression protects cells from genomic instability induced by staurosporine regardless of its upstream molecular effects.  相似文献   
33.
Summary Ventilatory response lines to carbon dioxide at rest were determined by the rebreathing method in 10 untrained subjects, 17 sprint swimmers, and 11 long-distance swimmers. It was found that the mean slope of the ventilatory response line of the swimmer was lower than that of the untrained group, and the mean slope of the long distance swimmer was lower as compared with the sprint swimmer, though these differences were statistically not significant. The differences in the hypercapnic drive between untrained subjects and swimmers obtained here is discussed in connection with their maximum oxygen uptake.  相似文献   
34.
Systemic hlstometrical and histological examinations of major skeletal muscles were performed by using autopsy cases with simple atrophy, neurogenic muscular atrophy, Duchenne type progressive muscular dystrophy, myositis of myasthenia gravis, and autopsy control cases. In hlstometrical studies, the shortest diameters of muscle fibers were measured and arranged in histograms. Volume ratio of stroma to muscle was measured by point-counting method.
Histometrical studies revealed the following results: (1) averages of muscle fiber diameters in controls showed the largest value In the muscles of the upper and lower extremities, and the smallest value in the lingual muscle; (2) in simple atrophy, neurogenic muscular atrophy, progressive muscular dystrophy and myositis, a decrease in muscle fiber diameters was more prominent in the muscles of the lower extremities than those of the upper extremities; (3) patterns of histograms of muscle fiber diameters were classified into six types, and in simple atrophy, almost one-half of muscles examined belonged to type 3 histogram, which had the mode situated at a relatively small diameter and a not so high kurtosls; (4) volume ratios of stroma to muscle Increased most in both muscular dystrophy and long-standing neurogenic muscular atrophy, moderately in myositis, and mildly in simple atrophy; and (5) hlstometrical changes In myasthenia gravis were minimal.  相似文献   
35.
Mice deficient in the plasminogen activator inhibitor-1 gene (PAI-1-/- mice) are relatively protected from developing pulmonary fibrosis from bleomycin administration. We hypothesized that one of the protective mechanisms may be the ability of the plasminogen system to enhance hepatocyte growth factor (HGF) effects, which have been reported to be anti-fibrotic in the lung. HGF is known to be sequestered in tissues by binding to extracellular matrix components. Following bleomycin administration, we found that HGF protein levels were higher in bronchoalveolar lavage fluid from PAI-1-/- mice compared to wild-type (PAI-1+/+) mice. This increase could be suppressed by administering tranexamic acid, which inhibits plasmin activity. Conversely, intratracheal instillation of urokinase into bleomycin-injured PAI-1+/+ mice to activate plasminogen caused a significant increase in HGF within bronchoalveolar lavage and caused less collagen accumulation in the lungs. Administration of an anti-HGF neutralizing antibody markedly increased collagen accumulation in the lungs of bleomycin-injured PAI-1-/- mice. These results support the hypothesis that increasing the availability of HGF, possibly by enhancing its release from extracellular matrix by a plasmin-dependent mechanism, is an important means by which activation of the plasminogen system can limit pulmonary fibrosis.  相似文献   
36.
37.
Brucella abortus is a facultative intracellular bacterium capable of surviving inside macrophages. Intracellular replication of B. abortus requires the VirB complex, which is highly similar to conjugative DNA transfer systems. In this study, we show that plasma membrane cholesterol of macrophages is required for the VirB-dependent internalization of B. abortus and also contributes to the establishment of bacterial infection in mice. The internalization of B. abortus was accelerated by treating macrophages with acetylated low-density lipoprotein (acLDL). Treatment of acyl coenzyme A:cholesterol acyltransferase inhibitor, HL-004, to macrophages preloaded with acLDL accelerated the internalization of B. abortus. Ketoconazole, which inhibits cholesterol transport from lysosomes to the cell surface, inhibited the internalization and intracellular replication of B. abortus in macrophages. The Niemann-Pick C1 gene (NPC1), the gene for Niemann-Pick type C disease, characterized by an accumulation of cholesterol in most tissues, promoted B. abortus infection. NPC1-deficient mice were resistant to the bacterial infection. Molecules associated with cholesterol-rich microdomains, "lipid rafts," accumulate in intracellular vesicles of macrophages isolated from NPC1-deficient mice, and the macrophages yielded no intracellular replication of B. abortus. Thus, trafficking of cholesterol-associated microdomains controlled by NPC1 is critical for the establishment of B. abortus infection.  相似文献   
38.
Purpose

Intravesical bacillus Calmette–Guérin (BCG) is the standard of care for bladder carcinoma in situ (CIS). The response to BCG therapy against CIS is generally assessed by random bladder biopsy (RBB). In this study, we examined the necessity of routine RBB after BCG therapy.

Methods

We retrospectively identified 102 patients who were initially diagnosed with CIS with or without papillary tumor and received subsequent 6–8-week BCG therapy. Thereafter, all patients underwent voiding cytology analysis, cystoscopy, and RBB to evaluate the effects of BCG therapy. We evaluated the association between clinical parameters (voiding cytology and cystoscopy findings) and the final pathological results by RBB specimens.

Results

According to the pathological results of RBB, 30 (29%) patients had BCG-unresponsive disease (remaining urothelial carcinoma was confirmed pathologically) and 20 were diagnosed with CIS. Positive/suspicious voiding cytology and positive cystoscopy findings were well observed in patients who had BCG-unresponsive disease compared with their counterparts (p?=?0.116, and p?<?0.001, respectively). The sensitivity (Sen.), specificity (Spe.), positive predictive value (PPV), and negative predictive value (NPV) of voiding cytology were 50%, 68%, 39%, and 77%, respectively. The values for cystoscopy findings were as follows: Sen.: 87%, Spe.: 57%, PPV: 46%, and NPV: 91%. The values for their combination (having either of them) were as follows: Sen.: 100%, Spe.: 44%, PPV: 43%, and NPV: 100%.

Conclusion

RBB after BCG therapy for patients with negative voiding cytology and negative cystoscopy may be omitted because their risk of BCG-unresponsive disease is significantly low (NPV: 100%).

  相似文献   
39.
There are no scoring methods for optimal treatment of patients with aneurysmal subarachnoid hemorrhage (aSAH). We developed a scoring model to predict clinical outcomes according to aSAH risk factors using data from the Japan Stroke Data Bank (JSDB). Of 5344 patients initially registered in the JSDB, 3547 met the inclusion criteria. Patients had been diagnosed with aSAH and treated with surgical clipping or endovascular coiling between 1998 and 2013. We performed multivariate logistic regression for poor outcomes at discharge, indicated by a modified Rankin Scale (mRS) score >2, and in-hospital mortality for both treatment methods. Based on each risk factor, we developed a scoring model assessing its validity using another dataset of our institution. In the surgical clipping group, scoring criteria for aSAH were age >72 years, history of more than once stroke, World Federation of Neurological Societies (WFNS) grades II–V, aneurysmal size >15 mm, and vertebrobasilar artery (VBA) aneurysm location. In the endovascular coiling group, scoring criteria were age >80 years, history of stroke, WFNS grades III–V, computed tomography (CT) Fisher group 4, and aneurysmal location in the middle cerebral artery (MCA) and anterior cerebral artery (ACA). The rates of poor outcome of mRS score >2 in an isolated dataset using these scoring criteria were significantly correlated with our model’s scores, so this scoring model was validated. This scoring model can help in the more objective treatment selection in patients with aSAH.  相似文献   
40.
ObjectivesTo investigate the association between Ki67 index and programmed death-ligand 1 (PD-L1) expression in muscle-invasive bladder cancer (MIBC) patients after RC.Materials and MethodsWe retrospectively evaluated 262 MIBC patients treated with RC between April 2004 and April 2020. The impact of Ki67 index and PD-L1 expression on prognosis was evaluated by univariate Cox regression analysis. In addition, a pathomolecular risk score, including Ki67 and PD-L1, was developed to predict prognosis and pathological factors. We also evaluated the link between the Ki67 index and PD-L1 under the IL-6 stimulation in the bladder cancer cell lines of T24 and 5637 cells.ResultsThe median age and follow-up period was 69 years and 52 months, respectively. Ki67 index and PD-L1 expression were significantly associated with tumor recurrence. Univariate Cox regression analysis showed that pT3–4, mixed histology, lymphovascular invasion positive (LVI+), pN+, Ki67-high (>17%), and PD-L1+ were significantly associated with recurrence-free survival (RFS). The pathomolecular risk score was developed using resection margin+ (1 point), mixed histology (1 point), LVI+ (1 point), pN+ (1 point), and Ki67-high (1 point). RFS and overall survival were significantly shorter in patients with higher pathomolecular risk scores (>1) than in those with lower risk scores (≤1). Cell proliferation was significantly increased in the T24 and 5637 cells under the IL-6 stimulation, while PD-L1 expression was not.ConclusionsA significant effect of Ki67-high and PD-L1 expression on poor prognosis was observed in patients with MIBC. Further studies are necessary to elucidate the precise mechanisms of cell proliferation and PD-L1 expression in patients with MIBC.  相似文献   
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