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941.
942.
Endogenous cannabinoids (EC) are ubiquitous lipid signalling molecules providing different central and peripheral effects that are mediated mostly by the specific receptors CB1 and CB2. The EC system is highly upregulated during chronic liver disease and consistent experimental and clinical findings indicate that it plays a role in the pathogenesis of liver fibrosis and fatty liver disease associated with obesity, alcohol abuse and hepatitis C. Furthermore, a considerable number of studies have shown that EC and their receptors contribute to the pathogenesis of the cardio‐circulatory disturbances occurring in advanced cirrhosis, such as portal hypertension, hyperdynamic circulatory syndrome and cirrhotic cardiomyopathy. More recently, the EC system has been implicated in the development of ascites, hepatic encephalopathy and the inflammatory response related to bacterial infection. Rimonabant, a selective CB1 antagonist, was the first drug acting on the EC system approved for the treatment of obesity. Unfortunately, it has been withdrawn from the market because of its neuropsychiatric side effects. Compounds able to target selectively the peripheral CB1 receptors are under evaluation. In addition, molecules stimulating CB2 receptor or modulating the activity of enzymes implicated in EC metabolism are promising areas of pharmacological research. Liver cirrhosis and the related complications represent an important target for the clinical application of these compounds.  相似文献   
943.
Aim: Based on the role of chitotriosidase (CHIT‐1) in the evolution of non‐alcoholic fatty liver disease, we explored whether CHIT‐1 mutant allele plays a role in NAFLD progression. Methods: We genotyped 200 patients with NAFLD (110 with non‐alcoholic steatohepatitis [NASH] and 90 with simple steatosis) and 100 control subjects. The χ2‐test was performed for a case–control study. Odds ratios (OR) were adjusted for age, sex and body mass index (BMI) by using multiple logistic regression analysis with genotypes (additive model), age, sex and BMI as the independent variables. Multiple linear regression analysis was performed to test the independent effect of risk allele on clinical parameters while considering the effects of other variables (age, sex and BMI), which were assumed to be independent of the effect of the single nucleotide polymorphism. Results: The risk allele frequency of CHIT‐1 wild type (Wt) was 0.71 in the control subjects, 0.77 in simple steatosis and 0.92 in patients with NASH. The OR (95% confidence interval) adjusted for age and BMI was 1.73. Multiple linear regression analysis indicated that the CHIT‐1 Wt was significantly associated with increases in ferritin levels (P = 0.014) and the fibrosis stage (P = 0.011) in the patients with NASH, even after adjustment for age, sex and BMI, corroborating that the presence of the CHIT‐1 Wt allele was an independent predictor of fibrotic NAFLD. In contrast, the steatosis grade was not associated with CHIT‐1 mutant allele. Conclusion: These findings suggest that a functional polymorphism in the CHIT‐1 gene protects against NAFLD progression.  相似文献   
944.
The prevalence of very severe obesity has increased progressively and faster than other classes of obesity over the last years. It is unclear whether the prevalence of obesity-related complications and health risks increases progressively or reaches a plateau above a certain degree of obesity. The aim of our study was to investigate whether the severity of obesity was correlated with the prevalence of type 2 diabetes mellitus (T2DM), impaired fasting glucose, impaired glucose tolerance (IGT), metabolic syndrome (MS), and cardiovascular diseases (CVDs) in a large cohort of patients with different degrees of obesity. A cross-sectional study was conducted in 938 obese patients without a previous diagnosis of diabetes. Patients were assigned to different categories of obesity: mild-moderate obesity (BMI 30–39.9 kg/m2), morbid obesity (BMI 40–49.9 kg/m2), and super-obesity (SO, BMI ≥50 kg/m2). The prevalence of IGF, IGT, screen-detected T2DM, MS, and CVD was higher in SO patients than in the other groups. Interestingly, the association between SO and either MS or CVD was independent of glucose tolerance status, indicating that factors other than glucose metabolism also favor cardio-metabolic complications in obese patients. In patients without screen-detected T2DM (n = 807), insulin sensitivity and secretion OGTT-derived indexes indicated that SO patients had the worst glucose homeostasis relative to the other categories of obesity, which was indicated by the most reduced disposition index in these patients, a predictor of future T2DM. In conclusion, SO patients have an extremely high prevalence of glucose metabolism deterioration, and cardio-metabolic complications are more prevalent in these patients compared to less obese patients.  相似文献   
945.
Midlife elevated blood pressure and hypertension contribute to the development of Alzheimer's disease (AD) and overall dementia. We sought to estimate whether angiotensin-converting enzyme inhibitors (ACE-Is) reduced the risk of developing mild cognitive impairment (MCI) in cognitively normal individuals. In the Italian Longitudinal Study on Aging, we evaluated 1,445 cognitively normal individuals treated for hypertension but without congestive heart failure from a population-based sample from eight Italian municipalities with a 3.5-year follow-up. MCI was diagnosed with current clinical criteria. Dementia, AD, and vascular dementia were diagnosed based on DSM-IIIR criteria, NINCDS–ADRDA criteria, and ICD-10 codes. Among 873 hypertension-treated cognitively normal subjects, there was no significant association between continuous exposure to all ACE-Is and risk of incident MCI compared with other antihypertensive drugs [hazard ratio (HR), 0.45, 95% confidence interval (CI), 0.16–1.28]. Captopril exposure alone did not significantly modify the risk of incident MCI (HR, 1.80, 95% CI, 0.39–8.37). However, the enalapril sub-group alone (HR, 0.17, 95% CI, 0.04 –0.84) or combined with the lisinopril sub-group (HR, 0.27, 95% CI, 0.08–0.96), another ACE-I structurally related to enalapril and with similar potency, were associated with a reduced risk of incident MCI. Study duration exposure to ACE-Is as a “class” was not associated with incident MCI in older hypertensive adults. However, within-class differences linked to different chemical structures and/or drug potencies may exist, with a possible effect of the enalapril and lisinopril sub-groups in reducing the risk of incident MCI.  相似文献   
946.

Purpose

The aim of this study is to evaluate the long-term outcome of patients with locally advanced breast cancer treated with neoadjuvant systemic chemotherapy (NST) in routine clinical practice.

Methods

Four hundred and nine patients were identified between January 1999 and December 2011. All patients received NST followed by surgery, adjuvant treatments and radiotherapy, as appropriate.

Results

At Kaplan–Meier analysis, patients with surgical stage III disease were more likely to develop distant metastasis and die from breast cancer (p < 0.001). Luminal A and luminal B/HER2-negative patients had better prognosis; moreover, patients with hormone receptor (HR)-positive tumors had a significantly longer DRFS (p < 0.0049) and OS (p < 0.0001) compared with patients with HR-negative tumors as well as patients who underwent breast-conserving surgery (DRFS and OS: p < 0.001). In multivariate analysis, HR negativity (p < 0.001 for both DRFS and OS), mastectomy (DRFS: p = 0.009; OS: p = 0.05) and stage III disease (DRFS: p < 0.001; OS: p = 0.003) were associated with shorter DRFS and OS.

Conclusions

HR negativity, mastectomy and pathological stage III disease are the variables independently associated with a worse outcome in our cohort of patients. These data are of high interest since they derive from a very heterogeneous group of patients, treated with different neoadjuvant/adjuvant regimens outside of clinical trials and with a long follow-up period.  相似文献   
947.
BackgroundGenetic alterations in the ATP-binding cassette subfamily B member 4 (ABCB4) and ATP-binding cassette subfamily B member 11 (ABCB11) have been associated to the onset of intrahepatic cholestasis of pregnancy (ICP) in predisposed women.AimsTo identify new and/or frequent ABCB4 and ABCB11 genes variants in a cohort of Italian patients with ICP and to evaluate the possible pathogenetic role for the novel mutations identified.MethodsDNA of 33 unrelated Italian women with obstetric cholestasis were screened for mutations in the entire coding sequence of ABCB4 and ABCB11 genes. Polymerase chain reaction and automated sequencing was performed on the 27 coding exons of both genes.ResultsGenotyping revealed 11 mutations, 5 of whom were novel variants: 2 localized on ABCB4 (p.I587DfsX603, p.I738LfsX744) and 3 on ABCB11 (p.V284D, p.Q558H, p.P731S). The most severe phenotypes were associated with the variants p.I587DfsX603, p.I738LfsX744 and p.V284D. Moreover, the already described mutation p.N510S found in ABCB4 seems to be strictly involved in the onset of ICP in that particular patient.ConclusionsOur data support the hypothesis of a significant involvement of ABCB4 mutations in the onset of ICP, but also confirm an important role for ABCB11 mutations in increasing the susceptibility to cholestasis of pregnancy.  相似文献   
948.
BackgroundIn 2007, sorafenib was the first drug able to improve overall survival in patients with advanced hepatocellular carcinoma.AimIn 2005 we designed a phase II study to assess safety and efficacy of sunitinib.MethodsThis is a single arm, open-label, single-centre phase II trial. Eligibility criteria were advanced hepatocellular carcinoma; no prior chemotherapy, performance status 0–1; and Child  B8. The treatment schedule was 50 mg each day orally, 4 weeks on, 2 weeks off.ResultsBetween 10/2007 and 10/2010, 34 patients were enrolled. A significant worsening of liver functional reserve after sunitinib was observed. Grade 3/4 adverse effects occurred in 80% of patients and included fatigue (47%), nausea (15%), liver failure (15%), encephalopathy (12%) and upper gastrointestinal bleeding (12%). Six patients (18%) died within 60 days of enrolment. A partial response was observed in 4 patients (12%). Median time to tumour progression was 2.8 months and median overall survival was 5.8 months.ConclusionA dose of 50 mg/d induces a high rate of severe adverse events. Toxicity remains a key concern also at the dose of 37.5 mg/d. However, sunitinib is able to induce a prolonged response in some patients. Positron Emission Tomography/Computed Tomography scans may select good responders.  相似文献   
949.
AIM: To investigate the clinical impact of capsule endoscopy (CE) after an obscure gastrointestinal bleeding (OGIB) episode, focusing on diagnostic work-up, follow-up and predictive factors of rebleeding.METHODS: Patients who were referred to Hospital del Mar (Barcelona, Spain) between 2007 and 2009 for OGIB who underwent a CE were retrospectively analyzed. Demographic data, current treatment with non-steroid anti-inflammtory drugs or anticoagulant drugs, hemoglobin levels, transfusion requirements, previous diagnostic tests for the bleeding episode, as well as CE findings (significant or non-significant), work-up and patient outcomes were analyzed from electronic charts. Variables were compared by χ2 analysis and Student t test. Risk factors of rebleeding were assessed by Log-rank test, Kaplan-Meier curves and Cox regression model.RESULTS: There were 105 patients [45.7% women, median age of 72 years old (interquartile range 56-79)] and a median follow-up of 326 d (interquartile range 123-641) included in this study. The overall diagnostic yield of CE was 58.1% (55.2% and 63.2%, for patients with occult OGIB and overt OGIB, respectively). In 73 patients (69.5%), OGIB was resolved. Multivariate analysis showed that hemoglobin levels lower than 8 g/dL at diagnosis [hazard ratios (HR) = 2.7, 95%CI: 1.9-6.3], patients aged 70 years and above (HR = 2.1, 95%CI: 1.2-6.1) and significant findings in CE (HR = 2.4, 95%CI: 1.1-5.8) were independent predictors of rebleeding.CONCLUSION: One third of the patients presented with rebleeding after CE; risk factors were hemoglobin levels < 8 g/dL, age ≥ 70 years or the presence of significant lesions.  相似文献   
950.
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