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European Archives of Oto-Rhino-Laryngology - To analyze the surgical outcomes in terms of postoperative wound complications in a small case series of six patients treated with lateral cervical...  相似文献   
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OBJECTIVE: Ghrelin, the endogenous ligand of growth hormone secretagogue receptor (GHS-R), acts on the pituitary and the hypothalamus to stimulate the release of growth hormone (GH) and promotes appetite and adiposity. It has also been reported to increase myocardial contractility, induce vasodilation, and protect against myocardial-infarction-induced heart failure. Though principally gastric in origin, it is also produced by other tissues. This work investigated whether cardiomyocytes synthesize and secrete ghrelin, and how its production in these cells responds to stress and exogenous apoptotic agents. METHODS: Ghrelin and its receptor expression was studied by RT-PCR, immunohistochemistry, and competitive binding studies in mouse adult cardiomyocyte cell line HL-1, and primary cultured human cardiomyocytes. Ghrelin accumulation in cardiomyocyte culture medium was measured by radioimmunoassay. Viability and apoptosis assays were carried on by MTT and Hoechst dye vital staining, respectively. RESULTS: RT-PCR showed that HL-1 cells produce mRNAs for both ghrelin and GHS-R, and that GHS-R1a is expressed in human cardiomyocytes; and competitive binding studies using (125)I-labelled ghrelin showed efficient constitutive expression of GHS-R at the surface of HL-1 cells. Immunohistochemistry confirmed the presence of ghrelin in the cytoplasm of HL-1 cells and of isolated human cardiomyocytes in primary culture. Radioimmunoassay showed that ghrelin was secreted by HL-1 cells and human cardiomyocytes into the culture medium. Ghrelin did not modify the viability of HL-1 cells subjected to 12-h starvation, but did protect against the apoptosis inducer cytosine arabinoside (AraC). Finally, production of ghrelin mRNA in HL-1 cardiomyocytes was reduced by AraC but increased if exposure to AraC was preceded by GH treatment. CONCLUSIONS: Ghrelin is synthesized and secreted by isolated murine and human cardiomyocytes, probably with paracrine/autocrine effects, and may be involved in protecting these cells from apoptosis.  相似文献   
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In obstructive sleep apnea, patients’ sleep is fragmented leading to excessive daytime sleepiness and co‐morbidities like arterial hypertension. However, traditional metrics are not always directly correlated with daytime sleepiness, and the association between traditional sleep quality metrics like sleep duration and arterial hypertension is still ambiguous. In a development cohort, we analysed hypnograms from mild (n = 209), moderate (n = 222) and severe (n = 272) obstructive sleep apnea patients as well as healthy controls (n = 105) from the European Sleep Apnea Database. We assessed sleep by the analysis of two‐step transitions depending on obstructive sleep apnea severity and anthropometric factors. Two‐step transition patterns were examined for an association to arterial hypertension or daytime sleepiness. We also tested cumulative distributions of wake as well as sleep‐states for power‐laws (exponent α) and exponential distributions (decay time τ) in dependency on obstructive sleep apnea severity and potential confounders. Independent of obstructive sleep apnea severity and potential confounders, wake‐state durations followed a power‐law distribution, while sleep‐state durations were characterized by an exponential distribution. Sleep‐stage transitions are influenced by obstructive sleep apnea severity, age and gender. N2 → N3 → wake transitions were associated with high diastolic blood pressure. We observed higher frequencies of alternating (symmetric) patterns (e.g. N2 → N1 → N2, N2 → wake → N2) in sleepy patients both in the development cohort and in a validation cohort (n = 425). In conclusion, effects of obstructive sleep apnea severity and potential confounders on sleep architecture are small, but transition patterns still link sleep fragmentation directly to obstructive sleep apnea‐related clinical outcomes like arterial hypertension and daytime sleepiness.  相似文献   
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The aim of the study was to assess how the analysis of different signals recorded during application of automatic continuous positive airway pressure (autoCPAP) devices improves the evaluation of pressure titration in patients with obstructive sleep apnea syndrome (OSAS) naive to treatment. Seventy-two patients underwent nocturnal polysomnography during autoCPAP (Autoset T, ResMed, Sydney, Australia) application. Progressively more complex combinations of signals were analysed in consecutive steps. According to the analysis of oxyhemoglobin saturation (SaO(2)) alone, a fixed CPAP level suitable for treatment could not be identified in 3 subjects. When analysis of posture was added, titration was considered unsatisfactory in 1 more subject, due to a short time spent supine. Further, addition of flow and respiratory movements led to consider titration unsatisfactory in 1 more subject. Analysis of all polysomnographic signals demonstrated a not fully reliable titration in 9 subjects: 1 with short sleep duration, 2 without REM sleep, 4 with a short sleep time spent supine, and 3 subjects (already identified by SaO(2)) with insufficient correction of respiratory disorders even when a relatively high CPAP was administered. Mask leaks did not hamper titration. CPAP titration by automatic devices alone results in imperfect titration in >10% subjects naive to ventilatory treatment. Only polysomnographic recording ensures titration reliability in all patients. Further research is needed to identify simple and economic methods to reliably start the CPAP treatment.  相似文献   
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BackgroundMigraine represents one of the most prevalent neurological conditions worldwide. It is a disabling condition with high impact on the working situation of migraineurs. Interestingly, gender-related differences regarding an association of migraine with important occupational characteristics has been hardly studied.MethodsThe current study scrutinizes gender-specific differences in the prevalence of migraine across a broad spectrum of occupational categories, shedding also light on associations with important job-related features such as shift work, job satisfaction, and physical activity. The study included data from 415 712 participants from the UK Biobank cohort, using the official ICD10 diagnosis of migraine and other health conditions as selection criteria. Prevalence ratios of migraineurs compared to healthy controls among different occupational categories and job-related variables were estimated using log-binomial regression analyses. Statistical models were adjusted for important sociodemographic features such as age, BMI, ethnicity, education and neuroticism. To better highlight specific differences between men and women we stratified by sex.ResultsWe detected a differential prevalence pattern of migraine in relation to different job categories between men and women. Especially in men, migraine appears to be more prevalent in highly physically demanding occupations (PR 1.38, 95% CI [0.93, 2.04]). Furthermore, migraine is also more prevalent in jobs that frequently involve shift or night shift work compared to healthy controls. Interestingly, this prevalence is especially high in women (shift work PR 1.45, 95% CI [1.14, 1.83], night shift work PR 1.46, 95% CI [0.93, 2.31]).ConclusionOur results show that migraine is genderdependently associated with physically demanding jobs and shift working.  相似文献   
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Aberrant promoter hypermethylation is a mechanism of tumour suppressor gene inactivation. We explored aberrant promoter hypermethylation of multiple genes in 88 human immunodeficiency virus (HIV)-non Hodgkin lymphomas (NHL), 25 post-transplant lymphoproliferative disorders (PTLD) and five common variable immunodeficiency (CVI)-related NHL. Twenty-six of 79 (32.9%) HIV-NHL, eight of 14 (57.1%) PTLD and two of five (40.0%) CVI-NHL showed aberrant hypermethylation of O6-methylguanine-DNA methyltransferase (MGMT). Aberrant hypermethylation of death-associated protein-kinase (DAP-K) occurred in 70 of 84 (83.3%) HIV-NHL, 19 of 25 (72.0%) PTLD and three of five (60.0%) CVI-NHL. These data implicate MGMT and DAP-K hypermethylation in lymphomagenesis of immunodeficient hosts. In particular, promoter hypermethylation of DAP-K represents the most frequent molecular alteration yet identified in immunodeficiency-related lymphomas.  相似文献   
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The goal of this study was to analyze the correlation between inducible nitric oxide synthase (iNOS) and COX-2 activities and p53 gene status in head and neck squamous cell carcinomas (HNSCCs) in vivo and in vitro. In a series of 43 HNSCCs we observed an up-regulation of both iNOS and COX-2 pathways in tumor tissues and both activities were correlated each other (rs = 0.612 and P = 0.0002). We also found that p53-mutated HNSCCs (25 cases, 58.1%) showed higher levels of iNOS activity and cGMP in comparison with wild-type p53 tumors (18 cases, 41.9%) (P = 0.0005 and P = 0.01), as well as higher iNOS immunohistochemical expression (P = 0.03). Analogously, higher PgE2 levels were documented in p53-mutated HNSCCs when compared with wild-type p53 tumors (P = 0.015) and COX-2 protein expression was higher in p53-mutated HNSCCs (P = 0.007). A431 cancer cells expressing a p53 temperature-sensitive mutant showed an approximately 1.9- and 2.6-fold decrease in spontaneous NO(2-)/NO(3-) and PgE2 synthesis at permissive temperature, respectively, when compared with the same cells at nonpermissive temperature (P 相似文献   
20.
To investigate the intra-hepatic activation of the IFN system in patients affected by chronic HCV-infection in comparison with that observed in a non-infectious liver disease such as non-alcoholic steatohepatitis, we measured the liver steady state mRNA levels of interferon-alpha, interferon-beta and interferon-gamma as well as of IFN-related genes (IFNAR-1, STAT1alpha, PKR, 2-5 AS, IRF-1, ICE and IL-18). In HCV-infected subjects, possible correlations of these parameters with viral load and liver injury were also analyzed. Twenty-four chronic untreated HCV-infected subjects and seven patients with non-alcoholic steatohepatitis were enrolled in the study. Liver biopsies were graded according to Knodell scores. Intra-hepatic mRNA levels of IFNs and related genes were assessed by semi-quantitative RT-PCR. In comparison with non-alcoholic steatohepatitis, in HCV-infected subjects IFN-alpha and -beta mRNA levels were significantly lower, whereas IFN-gamma, IFNAR-1, STAT1alpha IRF-1, and IL-18 mRNA were upregulated. Moreover, IFN-gamma mRNA steady state levels were correlated positively with those of IFNAR-1, IRF-1, and IL-18, suggesting a coordinated induction of these genes. Although plasma viral load was correlated inversely with IL-18-specific mRNA, viral load was not related to liver injury. IFN-gamma and IRF-1 mRNA levels were correlated positively with ALT, but not with the grading or staging. Conversely, IFN-alpha and -beta mRNA levels were higher in livers with lower staging scores. These findings support the hypothesis that in chronic HCV infection there is an imbalance between an upregulated IFN-gamma system and a downregulated IFN-alpha and -beta system, probably due to a mixed effect exerted by HCV-specific and inflammatory non-specific factors.  相似文献   
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