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991.
Cytogenetic studies of acute monoblastic leukemia cases presenting MLL-MLLT10 (alias MLL-AF10) fusion show a broad heterogeneity of chromosomal breakpoints. We present two new pediatric cases (French-American-British type M5) with MLL-MLLT10 fusion, which we studied with fluorescence in situ hybridization. In both we detected a paracentric inversion of the 11q region that translocated onto chromosome 10p12; one case displayed a variant complex pattern. We review the cytogenetic molecular data concerning the proximal inversion breakpoint of 11q and confirm its heterogeneity.  相似文献   
992.
IntroductionMortality from variceal bleeding remains high despite the therapeutic progress in severe cirrhosis. Understanding the predictive factors of failure to control bleeding (FTB) and mortality will lead to better future therapies. Comorbidities are thought to be important prognostic factors for variceal bleeding. The aim of the study was to assess the factors associated with FTB and with 42-day mortality and to evaluate the influence of comorbidities on these patients’ prognosis.Material and methodsWe prospectively included in the study all consecutive patients with cirrhosis and variceal bleeding presenting to the emergency room and we followed them up over 6 weeks. CirCom score and Charlson index were used for the assessment of comorbidities.ResultsOf the 138 patients included in the study, 27 (19.5%) were considered to have FTB. Child C class (74.07% vs. 32.43%, p < 0.001), Meld score (20.5 vs. 16.00, p = 0.004) and creatinine level (1.04 vs. 0.81, p = 0.01) were associated with FTB, but only Child class was independently associated with FTB in multivariate analysis (OR = 2.94, p = 0.006). Mortality at 42 days (21.7%) was influenced by the severity of the disease assessed through Child class (76.66% vs. 30.55% – Child C, p < 0.001) and MELD score (21.00 vs. 16.00, p < 0.001). Creatinine level (1.00 vs. 0.7, p = 0.02) and acute kidney injury (26.66% vs. 7.40%, p = 0.009) were also prognostic factors for the 6-week mortality. Comorbidities did not influence the mortality (CirCom > 1 (16.7% vs. 21.3%, p = 0.76) or Charlson index > 4 (36% vs. 47.2%, p = 0.41).ConclusionsThe severity of cirrhosis is an important prognostic factor for FTB and 42-day mortality. Identifying the factors associated with early mortality may help selecting patients needing more than conventional therapy.  相似文献   
993.
994.
Increased telomerase expression has been implicated in the pathogenesis of lung cancer and, since the primary cause of lung cancer is smoking, an association between telomerase reactivation and tobacco smoke has been proposed. In this work an investigation has been performed to assess the relationship between tobacco smoke exposure and telomerase activity (TA) in peripheral blood mononuclear cells of healthy smokers. The methylation status of the catalytic subunit of telomerase hTERT was concurrently investigated to assess the possible association between epigenetic modifications of hTERT and TA. Besides, the association between smoke and telomere length (TL) has been evaluated. Healthy monozygotic twins with discordant smoking habits were selected as study population to minimize inter‐individual differences because of demographic characteristics and genetic heterogeneity. Statistically significant higher values of TA and TL were observed in smokers compared to nonsmoker co‐twins. The multivariate analysis of data showed, besides smoking habits (P = 0.02), an influence of gender (P = 0.006) and BMI (P = 0.001) on TA and a borderline effect of gender (P = 0.05) on TL. DNA methylation analysis, focused on 100 CpG sites mapping in hTERT, highlighted nine CpG sites differentially methylated in smokers. When co‐twins were contrasted, selecting as variables the intra‐twin difference in TA and hTERT DNA methylation, a statistically significant inverse correlation (P = 0.003) was observed between TA and DNA methylation at the cg05521538 site. In conclusion, these results indicate an association of tobacco smoke with TA and TL and suggest a possible association between smoke‐induced epigenetic effects and TA in healthy smokers. Environ. Mol. Mutagen. 58:551–559, 2017. © 2017 Wiley Periodicals, Inc.  相似文献   
995.
OBJECTIVE: Many studies have reported that cognitive ability may be predictive of the functional outcome for patients with schizophrenia. However, no study has prospectively examined these aspects in schizophrenia and bipolar disorders simultaneously. The present study attempted to analyze if neurocognition and clinical status predicts the real-life functioning for patients with schizophrenia or bipolar I disorder, using a longitudinal design. METHOD: Forty-seven schizophrenic and 43 bipolar I outpatients were assessed twice with a neurocognitive battery (Executive Functions, Working Memory, Verbal Memory, Visual Memory, Visual-Motor Processing, Vigilance, Vocabulary and Motor Speed tasks), clinical scales (the Positive and Negative Symptom Scale, the Hamilton Rating Scale for Depression and the Clinician Administered Rating Scale for Mania) and functional outcome measures (the Global Assessment of Functioning Scale, the WHO's Disability Assessment Scale and occupational adaptation level) over a one-year follow-up period. The cognitive performance of the patients was compared, at baseline and one year later, with that of 25 healthy subjects. RESULTS: In schizophrenia patients, global functioning one year later was predicted by a composite neurocognitive score and three specific domain (verbal memory, motor speed, vocabulary). Symptoms appeared to explain less of the variance in functioning. In bipolar I patients, changes in the composite neurocognitive score over one year, deficits in the visual/motor processing domain, severity of symptoms (psychotic, excitatory and affective symptoms) and premorbid adjustment at the first assessment were the variables that better predicted functioning or disability changes over follow-up period. CONCLUSIONS: Although the relationships between cognition, symptoms and functional capacity differ for schizophrenia or bipolar I patients, neuropsychological performance seems to be a principal longitudinal predictor of functioning in both disorders. Baseline neurocognition and cognitive changes over 12 months predicted changes in functioning over the same period, but only in bipolar I patients. These cognitive domains could be potential neurocognitive endophenotypes (endophenocognitypes) with regard to bipolar I disorder.  相似文献   
996.
Adult soft tissue sarcomas are a heterogeneous group of tumors, including well-described subtypes by histological and genotypic criteria, and pleomorphic tumors typically characterized by non-recurrent genetic aberrations and karyotypic heterogeneity. The latter pose a diagnostic challenge, even to experienced pathologists. We proposed that gene expression profiling in soft tissue sarcoma would identify a genomic-based classification scheme that is useful in diagnosis. RNA samples from 51 pathologically confirmed cases, representing nine different histological subtypes of adult soft tissue sarcoma, were examined using the Affymetrix U95A GeneChip. Statistical tests were performed on experimental groups identified by cluster analysis, to find discriminating genes that could subsequently be applied in a support vector machine algorithm. Synovial sarcomas, round-cell/myxoid liposarcomas, clear-cell sarcomas and gastrointestinal stromal tumors displayed remarkably distinct and homogenous gene expression profiles. Pleomorphic tumors were heterogeneous. Notably, a subset of malignant fibrous histiocytomas, a controversialhistological subtype, was identified as a distinct genomic group. The support vector machine algorithm supported a genomic basis for diagnosis, with both high sensitivity and specificity. In conclusion, we showed gene expression profiling to be useful in classification and diagnosis, providing insights into pathogenesis and pointing to potential new therapeutic targets of soft tissue sarcoma.  相似文献   
997.
We have previously reported that acute administration of N(G)-nitro-l-arginine methyl ester (L-NAME) increases the mean arterial pressure (MAP) and heart rate (HR) in autonomic-blocked (CAB) anaesthetized rats. In the present study we examined whether thyroid and adrenal glands are involved in these pressor and chronotropic responses. Sprague-Dawley rats were studied after bilateral vagotomy and ganglionic blockade with hexamethonium (10 mg kg(-1)), and stabilization of MAP with infusion of phenylephrine (PE) (6 microg kg(-1) min(-1)). The rats were divided into groups: L, CAB; PE, CAB + PE bolus (6 microg kg(-1)); L-TX, thyroidectomy + CAB; L-AX, adrenalectomy + CAB; TX, only thyroidectomy; C, CAB. L, L-AX and L-TX groups received a bolus of l-NAME (7.5 mg kg(-1)). Triiodothyronine (T3), thyroxin (T4) and thyrotropin (TSH) levels were measured in L and L-TX rats before and after l-NAME administration. Reduced nicotamide adenine dinucleotide (NADPH) diaphorase activity was determined in heart and aorta of the TX group. The pressor response induced by l-NAME was similar in all groups. l-NAME-induced-tachycardia was associated with this rise in MAP. Adrenalectomy did not modify this chronotropic response, but it was attenuated by thyroidectomy. Thyroidectomy by itself decreased the circulating levels of T3 but it had no effect on the plasma levels of T4 and TSH. L and L-TX groups showed similar levels of circulating T4 and TSH, meanwhile the plasma level of T3 decreased in the L group. Nitric oxide synthase (NOS) activity in atria as well as in aorta was greater in the TX group compared with C. When autonomic influences are removed, the thyroid gland modulates intrinsic heart rate via a mechanism that involves, at least in part, the nitric oxide pathway.  相似文献   
998.
999.
The molecular epidemiology of Streptococcus pneumoniae isolates from carriage and cerebrospinal fluid (CSF) concurrently recovered from the same individual has not yet been reported. By using pulsed-field gel electrophoresis, we demonstrated the genetic linkage among strains from CSF and nasopharynges of two children with pneumococcal meningitis.  相似文献   
1000.
It was proposed recently that CEM CD4-positive T cells infected chronically by herpes simplex virus type 1 (HSV-1) and human immunodeficiency virus type 1 (HIV-1) (CEM(HSV/HIV)) may be used as a model for studying HIV/HSV interactions. To ascertain whether HSV-HIV coinfection of T lymphocytes has a role in promoting progression of lentiviral infection, T cells infected chronically by either HSV-1 (CEM(HSV)) or HIV-1 (CEM(HIV)) were challenged with a superinfecting dose of HIV-1 or HSV-1. The results show a positive influence on HIV growth when CEM(HIV) cells were superinfected with HSV-1 to an extent that was dependent on the multiplicity of superinfection used. In contrast, HIV superinfection of CEM(HSV) cells resulted in a delay of HIV-1 production and in a lack of HSV-mediated LTR transactivation. These effects were due to cell growth inhibition and apoptosis, resulting from persistent HSV-1 infection. Treatment of CEM(HSV) with acyclovir inhibited completely the HSV-1 cytopathic effects and allowed efficient HIV-1 replication. These data may be relevant in clarifying the role of HIV/HSV interaction in the pathogenesis of AIDS.  相似文献   
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