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991.
Thirty patients with acute human immunodeficiency virus (HIV) type 1 infection received a combination of 3 antiretroviral drugs (n=15) or 4 antiretroviral drugs plus hydroxyurea and interleukin-2 (n=15) for 24 months, followed by 1-3 structured therapeutic interruptions (STIs). Viral control, defined as maintaining plasma viremia <5000 copies/mL without therapy, was achieved in 14 cases. Lymphocyte subsets, plasma HIV-1 RNA loads, proviral DNA loads in peripheral blood mononuclear cells (PBMCs), residual HIV-1 RNA loads in PBMCs and in lymph node cells, and anti-p24 lymphoproliferative response were measured. In the multivariate analysis, proviral DNA loads in PBMCs and anti-p24 lymphoproliferative response assessed at 24 months were independently correlated with viral control after STI. These results enabled us to define a subgroup of patients for whom safe discontinuation of therapy initiated at acute infection was suitable and contributed to ascertaining priority for biological parameter assessment in future clinical trials.  相似文献   
992.
The mechanisms leading to malignant cell proliferation may differ between the different histologic forms of high-grade non-Hodgkin's lymphomas. To analyze the potential role of interleukin-6 (IL-6) as a growth factor for lymphomatous cells in these different forms, the in situ production of this cytokine was analyzed in lymphomatous samples taken from 24 patients, 18 of whom were human immunodeficiency virus (HIV) infected. Eleven Burkitt's lymphomas (BLs), seven diffuse large-cell lymphomas, and six immunoblastic lymphomas were studied. In situ hybridization experiments showed that the IL-6 gene was expressed in all tissues. The number of IL-6 gene-expressing cells was 7 times higher in the non-BLs than in the BLs, and it was 17 times higher than that of 14 control lymph nodes displaying a benign follicular hyperplasia. Analysis of individual cases indicated that the level of IL-6 gene expression was strongly correlated with the presence of immunoblasts within the malignant clone. In contrast, this level was not correlated with the presence of Epstein-Barr virus genome in the lymphoma or with the HIV status of patients. Immunohistochemical studies with an anti-IL-6 monoclonal antibody showed that IL-6 was produced in non-BLs, but not in BLs. In the former, IL-6 mainly originated from reactive, nonmalignant cells. Immunohistochemical analyses of non-BLs also showed that malignant cells produced the 80-Kd chain of the IL-6 receptor. Taken together, these results suggest that IL-6 may act as a growth factor in some forms of high-grade B lymphomas. The presence of immunoblasts may be an indicator of such forms.  相似文献   
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996.

Background

Understanding the intracellular mechanisms induced by remote ischemic preconditioning (RIPC) in the human left ventricle opens new possibilities for development of pharmacological cardioprotection against ischemia and reperfusion injury. In this study we investigated the effects of RIPC on mitochondrial function, activation of pro-survival protein kinase Akt and microRNA expression in left ventricular biopsies from patients undergoing coronary artery bypass surgery (CABG).

Methods

Sixty patients were randomized to control (n = 30) or RIPC (n = 30). A blood pressure cuff was applied to the arm of all patients preoperatively. The cuff remained deflated in control group, whereas RIPC was performed by 3 cycles of cuff inflation to 200 mm Hg for 5 min, separated by 5 min deflation intervals. Left ventricular biopsies were obtained before and 15 min after aortic declamping. The primary outcome was mitochondrial respiration measured in situ. Secondary outcomes were activation of protein kinase Akt, assessed by western immunoblotting, and expression of microRNAs assessed by array and real-time polymerase chain reaction.

Results

Mitochondrial respiration was preserved during surgery in patients receiving RIPC (+ 0.2 μmol O2/min/g, p = 0.69), and reduced by 15% in controls (− 1.5 μmol O2/min/g, p = 0.02). Furthermore, RIPC activated protein kinase Akt before aortic clamping (difference from control + 43.3%, p = 0.04), followed by increased phosphorylation of Akt substrates at reperfusion (+ 26.8%, p < 0.01). No differences were observed in microRNA expression.

Conclusions

RIPC preserves mitochondrial function and activates pro-survival protein kinase Akt in left ventricle of patients undergoing CABG. Modulation of mitochondrial function and Akt activation should be further explored as cardioprotective drug targets.Clinical Trial Registration: http://www.clinicaltrials.gov, unique identifier: NCT01308138.  相似文献   
997.
We assessed in a French regional healthcare network the distribution of treatments, prognostic factors, and outcome of 334 newly diagnosed acute myeloid leukemia patients aged 60 years or older over a 4‐year period of time (2007–2010). Patients were selected in daily practice for intensive chemotherapy (n = 115), azacitidine (n = 95), or best supportive care (n = 124). In these three groups, median overall survival was 18.9, 11.3, and 1.8 months, respectively. In the azacitidine group, multivariate analysis showed that overall survival was negatively impacted by higher age (P = 0.010 for one unit increase), unfavorable cytogenetics (P = 0.001), lymphocyte count <0.5 G/L (P = 0.015), and higher lactate dehydrogenase level (P = 0.005 for one unit increase). We compared the survival of patients treated by azacitidine versus intensive chemotherapy and best supportive care using time‐dependent analysis and propensity score matching. Patients treated by intensive chemotherapy had a better overall survival compared with those treated by azacitidine from 6 months after diagnosis, whereas patients treated by azacitidine had a better overall survival compared with those treated by best supportive care from 1 day after diagnosis. This study of “real life” practice shows that there is a room for low intensive therapies such as azacitidine in selected elderly acute myeloid leukemia patients. Am. J. Hematol. 89:E244–E252, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
998.
Hemophagocytic lymphohistiocytosis is a condition of immune dysregulation characterized by severe organ damage induced by a hyperinflammatory response and uncontrolled T-cell and macrophage activation. Secondary hemophagocytic lymphohistiocytosis typically occurs in association with severe infections or malignancies. Patients with acute myeloid leukemia may be prone to develop hemophagocytic lymphohistiocytosis because of an impaired immune response and a high susceptibility to severe infections. In a series of 343 patients treated by intensive chemotherapy over a 5-year period in our center, we identified 32 patients (9.3%) with fever, very high ferritin levels, and marrow hemophagocytosis (i.e. patients with hemophagocytic lymphohistiocytosis). Compared to patients without hemophagocytic lymphohistiocytosis, these 32 patients had hepatomegaly, pulmonary or neurological symptoms, liver abnormalities, lower platelet count and higher levels of C-reactive protein as well as prolonged pancytopenia. A microbial etiology for the hemophagocytosis was documented in 24 patients: 14 bacterial infections, 9 Herpesviridae infections and 11 fungal infections. The treatment of hemophagocytic lymphohistiocytosis consisted of corticosteroids and/or intravenous immunoglobulins along with adapted antimicrobial therapy. Patients with hemophagocytic lymphohistiocytosis had a median overall survival of 14.9 months, which was significantly shorter than that of patients without hemophagocytic lymphohistiocytosis (22.1 months) (P=0.0016). Hemophagocytic lymphohistiocytosis was significantly associated with a higher rate of induction failure, mainly due to deaths in aplasia. Hemophagocytic lymphohistiocytosis can be diagnosed in up to 10% of patients with acute myeloid leukemia undergoing intensive chemotherapy and is associated with early mortality. Fever, very high ferritin levels and marrow hemophagocytosis represent the cornerstone of the diagnosis. Further biological studies are needed to better characterize and recognize this syndrome in patients with acute myeloid leukemia.  相似文献   
999.
Sleep-dependent performance enhancement has been consistently reported after explicit sequential finger learning, even using motor imagery practice (MIP), but whether similar sleep benefits occur after explicit sequential gross motor learning with the lower limbs has been addressed less often. Here, we investigated both acquisition and consolidation processes in an innovative sequential footstep task performed either physically or mentally. Forty-eight healthy young participants were tested before and after physical practice (PP) or MIP on the footstep task, following either a night of sleep (PPsleep and MIPsleep groups) or an equivalent daytime period (PPday and MIPday groups). Results showed that all groups improved motor performance following the acquisition session, albeit the magnitude of enhancement in the MIP groups remained lower relative to the PP groups. Importantly, only the MIPsleep group further improved performance after a night of sleep, while the other groups stabilized their performance after consolidation. Together, these findings demonstrate a sleep-dependent gain in performance after MIP in a sequential motor task with the lower limbs but not after PP. Overall, the present study is of particular importance in the context of motor learning and functional rehabilitation.  相似文献   
1000.
Growing evidence supports a link between inflammation and cancer; however, mediators of the transition between inflammation and carcinogenesis remain incompletely understood. Sphingosine-1-phosphate (S1P) lyase (SPL) irreversibly degrades the bioactive sphingolipid S1P and is highly expressed in enterocytes but downregulated in colon cancer. Here, we investigated the role of SPL in colitis-associated cancer (CAC). We generated mice with intestinal epithelium-specific Sgpl1 deletion and chemically induced colitis and tumor formation in these animals. Compared with control animals, mice lacking intestinal SPL exhibited greater disease activity, colon shortening, cytokine levels, S1P accumulation, tumors, STAT3 activation, STAT3-activated microRNAs (miRNAs), and suppression of miR-targeted anti-oncogene products. This phenotype was attenuated by STAT3 inhibition. In fibroblasts, silencing SPL promoted tumorigenic transformation through a pathway involving extracellular transport of S1P through S1P transporter spinster homolog 2 (SPNS2), S1P receptor activation, JAK2/STAT3-dependent miR-181b-1 induction, and silencing of miR-181b-1 target cylindromatosis (CYLD). Colon biopsies from patients with inflammatory bowel disease revealed enhanced S1P and STAT3 signaling. In mice with chemical-induced CAC, oral administration of plant-type sphingolipids called sphingadienes increased colonic SPL levels and reduced S1P levels, STAT3 signaling, cytokine levels, and tumorigenesis, indicating that SPL prevents transformation and carcinogenesis. Together, our results suggest that dietary sphingolipids can augment or prevent colon cancer, depending upon whether they are metabolized to S1P or promote S1P metabolism through the actions of SPL.  相似文献   
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