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51.
Idiopathic CD4 T lymphocytopenia (ICL) is a rare and severe condition with limited available data. We conducted a French multicenter study to analyze the clinical and immunologic characteristics of a cohort of patients with ICL according to the Centers for Disease Control criteria.We recruited 40 patients (24 female) of mean age 44.2 ± 12.2 (19–70) years. Patients underwent T-lymphocyte phenotyping and lymphoproliferation assay at diagnosis, and experiments related to thymic function and interferon (IFN)-γ release by natural killer (NK) cell were performed. Mean follow-up was 6.9 ± 6.7 (0.14–24.3) years. Infectious, autoimmune, and neoplastic events were recorded, as were outcomes of interleukin 2 therapy.In all, 25 patients had opportunistic infections (12 with human papillomavirus infection), 14 had autoimmune symptoms, 5 had malignancies, and 8 had mild or no symptoms. At the time of diagnosis, the mean cell counts were as follows: mean CD4 cell count: 127/mm3 (range, 4–294); mean CD8: 236/mm3 (range, 1–1293); mean CD19: 113/mm3 (range, 3–547); and mean NK cell count: 122/mm3 (range, 5–416). Most patients had deficiency in CD8, CD19, and/or NK cells. Cytotoxic function of NK cells was normal, and patients with infections had a significantly lower NK cell count than those without (p = 0.01). Patients with autoimmune manifestations had increased CD8 T-cell count. Proliferation of thymic precursors, as assessed by T-cell rearrangement excision circles, was increased. Six patients died (15%). CD4 T-cell count <150/mm3 and NK cell count <100/mm3 were predictors of death.In conclusion, ICL is a heterogeneous disorder often associated with deficiencies in CD8, CD19, and/or NK cells. Long-term prognosis may be related to initial CD4 and NK cell deficiency.Abbreviations: AIHA = autoimmune hemolytic anemia, CDC = Centers for Disease Control, CMV = cytomegalovirus, cpm = count per minute, CVID = common variable immunodeficiency, CXCR4 = C-X-C chemokine receptor type 4, HIV = human immunodeficiency virus, HLA = human leukocyte antigen, HPV = human papillomavirus, HTLV-1/2 = human T-cell lymphotropic 1/2, ICL = idiopathic CD4 T lymphocytopenia, IFN-γ = interferon-γ, IL = interleukin, JC virus = John Cunningham virus, LPA = lymphocyte proliferation assay, NK = natural killer, P = patient, PBMC = peripheral blood mononuclear cell, Pwd = pokeweed, SI = stimulation index, sj = signal joint, TREC = T-cell rearrangement excision circle  相似文献   
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Introduction: The purpose of this study was to evaluate the relationship among sensory function, disease severity, and upper extremity force production in adults with type II diabetes (T2D) as compared with healthy age‐ and gender‐matched controls. Methods: Ten adults with T2D and 10 healthy age‐ and gender‐matched control subjects underwent a battery of sensory and motor function evaluations. Data on disease severity and duration were also collected. Results: The T2D group exhibited sensory deficits and altered force production as compared with healthy controls. Sensory function correlated with disease severity, as did signal predictability of kinetic output during submaximal force production tasks. Maximal force production tasks were associated with altered output in T2D, but these data did not correlate with disease severity or sensory dysfunction. Conclusions: Some, not all, motor performance deficits in T2D are associated with sensory dysfunction. Mechanisms responsible for these changes in adult‐onset T2D are described. Muscle Nerve 50: 984–990, 2014  相似文献   
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The incidence rates of melanoma have increased steadily in recent decades and nearly 25% of the patients diagnosed with early-stage melanoma will eventually develop metastasis, for which there is currently no fully effective treatment. The link between phospholipases and tumors has been studied extensively, particularly in breast and colon cancers. With the aim of finding new biomarkers and therapeutic options for melanoma, the expression of different phospholipases was assessed in 17 distinct cell lines in the present study, demonstrating that phospholipase D2 (PLD2) is upregulated in metastatic melanoma as compared to normal skin melanocytes. These results were corroborated by immunofluorescence and lipase activity assays. Upregulation of PLD2 expression and increased lipase activity were observed in metastatic melanoma relative to normal skin melanocytes. So far, the implication of PLD2 activity in melanoma malignancies has remained elusive. To the best of our knowledge, the present study was the first to demonstrate that the overexpression of PLD2 enhances lipase activity, and its effect to increase the proliferation, migration and invasion capacity of melanoma cells was assessed with XTT and Transwell assays. In addition, silencing of PLD2 in melanoma cells reduced the metastatic potential of these cells. The present study provided evidence that PLD2 is involved in melanoma malignancy and in particular, in its metastatic potential, and established a basis for future studies evaluating PLD2 blockade as a therapeutic strategy to manage this condition.  相似文献   
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Hydrophobic bile salts induce either necrosis or apoptosis depending on the severity of the injury caused by them. Since bile salt-induced apoptosis is influenced by Ca2+- and protein kinase-signaling pathways, and both necrosis and apoptosis share common initiating mechanisms, we analyzed whether these signaling cascades also influence bile salt-induced necrosis in isolated rat hepatocytes. Taurochenodeoxycholate (TCDC, 0.25-1.50 mM, 2 h) reduced, in a dose-dependent manner, the percentage of viable hepatocytes, and increased the release of the cytosolic enzyme, lactate dehydrogenase (LDH) and alanine aminotransferase (ALAT), and that of the plasma membrane enzyme, alkaline phosphatase (AP). The PKC inhibitors, H7 (100 microM) and chelerythrine (2.5 microM), both prevented significantly TCDC-induced necrosis. On the contrary, the PKA activator, dibutyryl-cAMP, exacerbated TCDC-induced cell damage in a dose-dependent manner; this effect was more likely due to cAMP-mediated PKA activation, as the PKA inhibitor, KT5720 (1 microM), counteracted this effect. Instead, the intracellular Ca2+ chelator, BAPTA/AM (20 microM), was without effect. TCDC (1 mM) increased lipid peroxidation from 0.7 +/- 0.2 to 7.5 +/- 0.9 nmol of malondialdehyde per mg of protein, p < 0.001; the addition of the free radical scavenger, diphenyl-p-phenylendiamine, completely blocked this increase and prevented significantly TCDC-induced necrosis. PKC inhibition induced only a slight attenuation of TCDC-induced lipid peroxidation. Possible mechanisms accounting for the modulatory effect of signal transduction pathways on TCDC-induced necrosis, including signaling influence on TCDC transport events and TCDC-induced oxidative stress, are discussed.  相似文献   
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Mortality after hospitalization for COPD   总被引:20,自引:0,他引:20  
OBJECTIVES: To identify variables associated with mortality in patients admitted to the hospital for acute exacerbation of COPD. DESIGN: Prospective cohort study. SETTING: Acute-care hospital in Barcelona (Spain). PATIENTS: One hundred thirty-five consecutive patients hospitalized for acute exacerbation of COPD, between October 1996 and May 1997. MEASUREMENTS AND RESULTS: Clinical, spirometric, and gasometric variables were evaluated at the time of inclusion in the study. Socioeconomic characteristics, comorbidity, dyspnea, functional status, depression, and quality of life were analyzed. Mortality at 180 days, 1 year, and 2 years was 13.4%, 22%, and 35.6%, respectively. Sixty-four patients (47.4%) were dead at the end of the study (median follow-up duration, 838 days). Greater mortality was observed in the bivariate analysis among the oldest patients (p < 0.0001), women (p < 0.01), and unmarried patients (p < 0.002). Hospital admission during the previous year (p < 0.001), functional dependence (Katz index) [p < 0.0004], greater comorbidity (Charlson index) [p < 0.0006], depression (Yesavage Scale) [p < 0.00001]), quality of life (St. George's Respiratory Questionnaire [SGRQ]) [p < 0.01], and PCO(2) at discharge (p < 0.03) were also among the significant predictors of mortality. In the multivariate analysis, the activity SGRQ subscale (p < 0.001; odds ratio [OR], 2.62; confidence interval [CI], 1.43 to 4.78), comorbidity (p < 0.005; OR, 2.2; CI, 1.26 to 3.84), depression (p < 0.004; OR, 3.6; CI, 1.5 to 8.65), hospital readmission (p < 0.03; OR, 1.85; CI, 1.26 to 3.84), and marital status (p < 0.0002; OR, 3.12; CI, 1.73 to 5.63) were independent predictors of mortality. CONCLUSIONS: Quality of life, marital status, depressive symptoms, comorbidity, and prior hospital admission provide relevant information of prognosis in this group of COPD patients.  相似文献   
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