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991.
992.
We used ultra-deep pyrosequencing and the Toulouse Tropism Test phenotypic assay to determine the prevalence of CXCR4-using viruses in 21 patients with primary HIV-1 infections. We found X4-containing virus populations in 9% of patients by ultra-deep pyrosequencing using position-specific scoring matrices (PSSM(X4/R5)) or geno2pheno(5.75) and in 14% using the combined 11/25 and net charge rule. The phenotypic assay identified 9% of CXCR4-using viruses. This confirms that R5 viruses are predominant in primary HIV-1 infections.  相似文献   
993.
The efficacy of ibrutinib has been demonstrated in patients with chronic lymphocytic leukemia (CLL), including as first-line therapy. However, outcomes after ibrutinib discontinuation have previously been limited to higher-risk populations with relapsed/refractory (R/R) disease. The objective of this study was to evaluate outcomes of ibrutinib-treated patients based on prior lines of therapy, including after ibrutinib discontinuation. Data were analyzed from two multicenter phase 3 studies of single-agent ibrutinib: RESONATE (PCYC-1112) in patients with R/R CLL and RESONATE-2 (PCYC-1115) in patients with treatment-naive (TN) CLL without del(17p). This integrated analysis included 271 ibrutinib-treated non-del(17p) patients with CLL (136 TN and 135 R/R). Median progression-free survival (PFS) was not reached for subgroups with 0 and 1/2 prior therapies but was 40.6 months for patients with ≥3 therapies (median follow-up: TN, 36 months; R/R, 44 months). Median overall survival (OS) was not reached in any subgroup. Overall response rate (ORR) was 92% in TN and 92% in R/R, with depth of response increasing over time. Adverse events (AEs) and ibrutinib discontinuation due to AEs were similar between patient groups. Most patients (64%) remain on treatment. OS following discontinuation was 9.3 months in R/R patients (median follow-up 18 months, n = 51) and was not reached in TN patients (median follow-up 10 months, n = 30). In this integrated analysis, ibrutinib was associated with favorable PFS and OS, and high ORR regardless of prior therapies in patients with CLL. The best outcomes following ibrutinib discontinuation were for patients receiving ibrutinib in earlier lines of therapy.  相似文献   
994.
995.
The purpose of promoting "use of self" or "self-disclosures" as a teaching strategy in teaching the P.A.T.H.S. curriculum is to create an interactive environment between teachers and students which can enhance the interactions between both parties. This article focuses on three major consequences of utilizing self-disclosures in the education settings, including humanizing the classroom, encouraging students' openness, and promoting teachers' awareness and reflective practice. Positive feedback of the participants of the Secondary 3 P.A.T.H.S. training programs show that participants were moved by the training instructors, who demonstrated the power of "use of self" in a humanistic manner. To retain a humanized and open classroom atmosphere depends greatly on the relational exchanges between teachers and students. This revelation should be purposeful and intentional, with appropriate boundaries and frequencies. Acknowledging the issues to consider in using "use of self" as a teaching strategy, teachers should focus attention on the process of connecting students with them. Guidelines for worker's self-disclosure are also discussed.  相似文献   
996.
The optimal management of patients with relapsed chronic lymphocytic leukemia (CLL) is dictated by the type of prior therapy, duration of prior response, presence of genomic aberrations, age, and comorbidities. The patterns of relapses and the clinical outcomes of second‐line options after fludarabine‐cyclophosphamide‐rituximab (FCR) is given as a frontline treatment are currently unknown. In this retrospective and non‐randomized study, we report the outcomes of 132 patients from databases of 14 French CLL study group centers who needed a second‐line treatment after FCR frontline. Bendamustine + rituximab (BR) was the most frequently used second‐line regimen, followed by alemtuzumab‐based regimens, R‐CHOP, and FCR. Median progression‐free survival (PFS) was 18 months after BR with a median overall survival (OS) not reached. We also found that response durations of < 36 months and the presence of del(17p) are critical factors that contribute to poor overall survival. BR appears to be an effective salvage regimen in our series, both in terms of progression‐free and overall survival. Patients who relapsed less than 36 months after FCR have a poor outcome, not significantly different in this study from patients with early relapses less than 12 or 24 months. Am. J. Hematol. 90:511–514, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
997.
In this report, we have assessed the lineage relationships and cytokine dependency of natural killer (NK) T cells compared with mainstream TCR-αβ T cells and NK cells. For this purpose, we studied common γ chain (γc)-deficient mice, which demonstrate a selective defect in CD3 NK cell development relative to conventional TCR-αβ T cells. NK thymocytes differentiate in γc mice as shown by the normal percentage of TCR Vβ8+ CD4CD8 cells and the normal quantity of thymic Vα14–Jα281 mRNA that characterize the NK T repertoire. However, γc-deficient NK thymocytes fail to coexpress the NK-associated markers NKR-P1 or Ly49, yet retain characteristic expression of the cytokine receptors interleukin (IL)-7Rα and IL-2Rβ. Despite these phenotypic abnormalities, γc NK thymocytes could produce normal amounts of IL-4. These results define a maturational progression of NK thymocyte differentiation where intrathymic selection and IL-4–producing capacity can be clearly dissociated from the acquisition of the NK phenotype. Moreover, these data suggest a closer ontogenic relationship of NK T cells to TCR-αβ T cells than to NK cells with respect to cytokine dependency. We also failed to detect peripheral NK T cells in these mice, demonstrating that γc-dependent interactions are required for export and/or survival of NK T cells from the thymus. These results suggest a stepwise pattern of differentiation for thymically derived NK T cells: primary selection via their invariant TCR to confer the IL-4–producing phenotype, followed by acquisition of NK-associated markers and maturation/export to the periphery.  相似文献   
998.
According to current understanding, cytoplasmic events including activation of protease cascades and mitochondrial permeability transition (PT) participate in the control of nuclear apoptosis. However, the relationship between protease activation and PT has remained elusive. When apoptosis is induced by cross-linking of the Fas/APO-1/CD95 receptor, activation of interleukin-1β converting enzyme (ICE; caspase 1) or ICE-like enzymes precedes the disruption of the mitochondrial inner transmembrane potential (ΔΨm). In contrast, cytosolic CPP32/ Yama/Apopain/caspase 3 activation, plasma membrane phosphatidyl serine exposure, and nuclear apoptosis only occur in cells in which the ΔΨm is fully disrupted. Transfection with the cowpox protease inhibitor crmA or culture in the presence of the synthetic ICE-specific inhibitor Ac-YVAD.cmk both prevent the ΔΨm collapse and subsequent apoptosis. Cytosols from anti-Fas–treated human lymphoma cells accumulate an activity that induces PT in isolated mitochondria in vitro and that is neutralized by crmA or Ac-YVAD.cmk. Recombinant purified ICE suffices to cause isolated mitochondria to undergo PT-like large amplitude swelling and to disrupt their ΔΨm. In addition, ICE-treated mitochondria release an apoptosis-inducing factor (AIF) that induces apoptotic changes (chromatin condensation and oligonucleosomal DNA fragmentation) in isolated nuclei in vitro. AIF is a protease (or protease activator) that can be inhibited by the broad spectrum apoptosis inhibitor Z-VAD.fmk and that causes the proteolytical activation of CPP32. Although Bcl-2 is a highly efficient inhibitor of mitochondrial alterations (large amplitude swelling + ΔΨm collapse + release of AIF) induced by prooxidants or cytosols from ceramide-treated cells, it has no effect on the ICE-induced mitochondrial PT and AIF release. These data connect a protease activation pathway with the mitochondrial phase of apoptosis regulation. In addition, they provide a plausible explanation of why Bcl-2 fails to interfere with Fas-triggered apoptosis in most cell types, yet prevents ceramide- and prooxidant-induced apoptosis.  相似文献   
999.
Dipeptidyl peptidase-4 (DPP4) inhibitors are a novel therapy widespread used in type 2 diabetes mellitus. We describe 3 cases of polyarthritis which delay of appearance strongly suggests a link with DPP4 inhibitors. Three patients presented with bilateral, symmetrical, seronegative polyarthritis after introduction of DPP4 inhibitors (sitagliptine (n = 2) and vildagliptine (n = 1)). Two patients also developed xerostomia and xerostomia, and laboratory test results showed normal values of CRP and erythrocyte sedimentation rate. Joints X-rays were normal. One patient was diagnosed with primary Sjögren’s syndrome and treated with hydroxychloroquine, methotrexate and prednisone, with a poor efficacy. When sitagliptine was stopped, all symptoms disappeared, leading to methotrexate and prednisone discontinuation within a month. There were no immunological abnormalities in the 2 other patients, but a chronic viral hepatitis B was found in one patient. Eventually, discontinuation of DPP4 inhibitors led to resolution of symptoms in 1 and 3 weeks for both patients. DPP4 inhibitors seemed to trigger bilateral, non-erosive, seronegative polyarthritis in our 3 patients. DPP4, also known as CD26, is expressed on many cells including lymphocytes and fibroblasts, and its inhibition may lead to immunomodulating effect as suggested by clinical and in vitro studies.  相似文献   
1000.
In disease-endemic areas, histoplasmosis is the main differential diagnosis for tuberculosis among human immunodeficiency virus (HIV)–infected patients. However, no study has compared the two diseases. Thus, the objective of this study was to compare tuberculosis and histoplasmosis in HIV-infected patients. A population of 205 HIV-infected patients (99 with tuberculosis and 106 with histoplasmosis) hospitalized in Cayenne, French Guiana during January 1, 1997–December 31, 2008 were selected retrospectively from the French Hospital Database on HIV. Multivariate analysis showed that tuberculosis was associated with cough (adjusted odds ratio [AOR] = 0.20, 95% confidence interval [CI] = 0.05–0.73) and a C-reactive protein level > 70 mg/L (AOR = 0.98, 95% CI = 0.97–0.99). Variables associated with disseminated histoplasmosis were a γ-glutamyl transferase level > 72 IU/L (AOR = 4.99, 95% CI = 1.31–18.99), origin from French Guiana (AOR = 5.20, 95% CI = 1.30–20.73), disseminated localization (AOR = 6.40, 95% CI = 1.44–28.45), a concomitant opportunistic infection (AOR = 6.71, 95% CI = 1.50–29.96), a neutrophil count < 2,750 cells/mm3 (AOR = 10.54, 95% CI = 2.83–39.24), a CD4 cell count < 60 cells/mm3 (AOR = 11.62, 95% CI = 2.30–58.63), and a platelet count < 150,000/mm3 (AOR = 19.20, 95% CI = 3.35–110.14). Tuberculosis and histoplasmosis have similarities, but some factors show a greater association with one of these diseases. Thus, adapted therapeutic choices can be made by using simple clinical and paraclinical criteria.  相似文献   
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