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11.
Alström Syndrome (ALMS), a recessive, monogenic ciliopathy caused by mutations in ALMS1, is typically characterized by multisystem involvement including early cone‐rod retinal dystrophy and blindness, hearing loss, childhood obesity, type 2 diabetes mellitus, cardiomyopathy, fibrosis, and multiple organ failure. The precise function of ALMS1 remains elusive, but roles in endosomal and ciliary transport and cell cycle regulation have been shown. The aim of our study was to further define the spectrum of ALMS1 mutations in patients with clinical features of ALMS. Mutational analysis in a world‐wide cohort of 204 families identified 109 novel mutations, extending the number of known ALMS1 mutations to 239 and highlighting the allelic heterogeneity of this disorder. This study represents the most comprehensive mutation analysis in patients with ALMS, identifying the largest number of novel mutations in a single study worldwide. Here, we also provide an overview of all ALMS1 mutations identified to date.  相似文献   
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The long-term changes of liver stiffness (LS) in patients who achieve viral clearance after direct-acting anti-HCV therapy remain undefined. We conducted a multicentre prospective study to investigate this aspect. Patients with HCV infection treated with DAAs were enrolled from six Italian centres; they underwent clinical, biochemical, ultrasound and transient elastography evaluations before treatment (T0), 12 weeks (SVR12) and 24 months (T24) after the end of therapy. Among the 516 consecutive patients enrolled, 301 had cirrhosis. LS significantly decreased from T0 to SVR (14.3 vs 11.1 kPa, p = .002), with a progressive reduction until T24 (8.7 kPa, p < .001). However, only patients with steatosis and those who developed HCC did not experience a late improvement in LS. Multivariate analysis of baseline and follow-up variables identified steatosis as the only independent predictor of failure of LS improvement (OR 1.802, p = .013). ROC curve analysis of the association of LS with the risk of developing HCC showed that SVR12 ≥14.0 kPa had the highest accuracy (sensitivity 82%, specificity 99%; AUC: 0.774). Multivariate analysis revealed that LS was the only variable independently associated with an increased risk of developing HCC (OR 6.470, p = .035). Achieving an SVR was associated with a progressive, long-term decline of LS, suggesting a late improvement in liver fibrosis, besides the resolution of inflammation. Fatty liver and the development of HCC interfered with late reduction of LS. Patients with an LS ≥14 kPa at 12 weeks after the end of treatment were at higher risk for developing HCC.  相似文献   
13.
BACKGROUNDOne third of coronavirus disease 2019 (COVID-19) patients have gastrointestinal symptoms. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA has been detected in stool samples of approximately 50% of COVID-19 individuals. Fecal calprotectin is a marker of gastrointestinal inflammation in the general population.AIMTo investigate if fecal calprotectin correlates with SARS-CoV-2 intestinal shedding in COVID-19 patients with pneumonia.METHODSPatients with SARS-CoV-2 pneumonia admitted to the Infectious Disease Unit (University Hospital of Trieste, Italy) from September to November 2020 were consecutively enrolled in the study. Fecal samples were collected and analyzed for quantification of fecal calprotectin (normal value < 50 mg/kg) and SARS-CoV-2 RNA presence by polymerase chain reaction (PCR). Inter-group differences were determined between patients with and without diarrhea and patients with and without detection of fecal SARS-CoV-2.RESULTSWe enrolled 51 adults (40 males) with SARS-CoV-2 pneumonia. Ten patients (20%) presented with diarrhea. Real-time-PCR of SARS-CoV-2 in stools was positive in 39 patients (76%), in all patients with diarrhea (100%) and in more than two thirds (29/41, 71%) of patients without diarrhea. Obesity was one of the most common comorbidities (13 patients, 25%); all obese patients (100%) (P = 0.021) tested positive for fecal SARS-CoV-2. Median fecal calprotectin levels were 60 mg/kg [interquartile range (IQR) 21; 108]; higher fecal calprotectin levels were found in the group with SARS-CoV-2 in stools (74 mg/kg, IQR 29; 132.5) compared to the group without SARS-CoV-2 (39 mg/kg, IQR 14; 71) (P < 0.001).CONCLUSIONHigh fecal calprotectin levels among COVID-19 patients correlate with SARS-CoV-2 detection in stools supporting the hypothesis that this virus can lead to bowel inflammation and potentially to the ‘leaky gut’ syndrome.  相似文献   
14.
Systemic Lupus Erythematosus (SLE) is a multifactorial autoimmune disease affecting different organs or systems. Several genes have been associated with SLE susceptibility so far. A previous study has reported, in SLE patients, a differential expression of Fyn Binding Protein gene (FYB), encoding for a protein participating in the T cells signaling cascade and in the interleukin-2A expression modulation.  相似文献   
15.
A linear β-amino alcohol ligand, previously found to be a very efficient catalyst for enantioselective addition of dialkylzinc to aromatic aldehydes, has been anchored on differently functionalized superparamagnetic core–shell magnetite–silica nanoparticles (1a and 1b). Its catalytic activity in the addition of dialkylzinc to aldehydes has been evaluated, leading to promising results, especially in the case of 1b for which the recovery by simple magnetic decantation and reuse was successfully verified.

The catalytic activity of a linear β-amino alcohol ligand anchored on functionalized magnetite/silica core–shell nanoparticles has been evaluated in the addition of dialkylzinc to aldehydes leading to promising results.  相似文献   
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Our previous studies have shown that stimulation of the anteroventral third ventricle (AV3V) region of the brain increases atrial natriuretic peptide (ANP) release, whereas lesions of the AV3V region or median eminence of the tuber cinereum block the release of ANP caused by blood volume expansion. These results suggest that participation of the central nervous system is critical to this response. The role of baroreceptors in the response was evaluated in the current research by studying the response of plasma ANP to blood volume expansion induced by intravenous injection of hypertonic saline solution (0.3 M NaCl, 2 ml/100 g of body weight, over 1 min) in conscious, freely moving male rats. Plasma samples were assayed for ANP by radioimmunoassay. In sham-operated rats, blood volume expansion induced a rapid increase in plasma ANP: the concentration peaked at 5 min and remained elevated at 15 min after saline injection. One week after deafferentation of the carotid-aortic baroreceptors, basal plasma ANP concentrations were highly significantly decreased on comparison with values of sham-operated rats; plasma ANP levels 5 min after blood volume expansion in the deafferented rats were greatly reduced. Unilateral right vagotomy reduced resting levels of plasma ANP but not the response to blood volume expansion; resting concentrations of plasma ANP and responses to expansion were normal in bilaterally vagotomized rats. In rats that had undergone renal deafferentation, resting levels of ANP were normal but the response to blood volume expansion was significantly suppressed. The evidence indicates that afferent impulses via the right vagus nerve may be important under basal conditions, but they are not required for the ANP release induced by blood volume expansion. In contrast, baroreceptor impulses from the carotid-aortic sinus regions and the kidney are important pathways involved in the neuroendocrine control of ANP release. The evidence from these experiments and our previous stimulation and lesion studies indicates that the ANP release in response to volume expansion is mediated by afferent baroreceptor input to the AV3V region, which mediates the increased ANP release via activation of the hypothalamic ANP neuronal system.  相似文献   
18.
It is uncertain whether patients with nonalcoholic fatty liver disease (NAFLD) and normal alanine aminotransferase (ALT) have a milder disease and should undergo liver biopsy. We reviewed the histological data of 458 Italian patients with NAFLD in whom liver biopsy was indicated by altered liver enzymes (395 cases, 86%), or persistently elevated ferritin or long-lasting severe steatosis (63 cases). Factors associated with nonalcoholic steatohepatitis (NASH) and fibrosis >/= 2 were identified by multivariate analysis. Patients with normal ALT were significantly older, had lower body mass index, fasting triglycerides, insulin resistance according to homeostasis model assessment (HOMA-IR), ALT, and gamma-glutamyltransferase, but a higher prevalence of hypertension. NASH was diagnosed in 59% and 74% of the patients with normal and increased ALT, respectively (P = 0.01). In the overall series of patients, NASH was independently predicted by ALT (odds ratio [OR], 1.11; 95% confidence interval [CI], 1.04-1.19 per 10-IU/mL increase) and diabetes (OR, 1.5; 95% CI, 1.1-2.0). The same variables were selected in patients with increased ALT, whereas in those with normal ALT, HOMA-IR and ALT were independent predictors. Severe fibrosis was independently predicted by serum ferritin (OR, 1.04; 95% CI, 1.001-1.08 per 50-ng/mL increase), ALT (OR, 1.07; 95% CI, 1.02-1.14), and diabetes (OR, 1.8; 95% CI, 1.4-2.3) in the overall series, serum ferritin and diabetes in those with increased ALT, and only HOMA-IR (OR, 1.97; 95% CI, 1.2-3.7) in patients with normal ALT. CONCLUSION: Normal ALT is not a valuable criterion to exclude patients from liver biopsy. Alterations in glucose metabolism and insulin resistance in subjects with normal ALT should also be considered in the selection of NAFLD cases for histological assessment of disease severity and progression.  相似文献   
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The treatment of elderly patients with coronary artery disease (CAD) is challenging because this population is complex and greatly expanding. Drug-eluting stents (DES) generally improve the outcome in high-risk cases. We evaluated the clinical impact of different first-generation DES, i.e., sirolimus-eluting stents (SES) and paclitaxel-eluting stents (PES), in this context. A prospective, nonrandomized, single-center, allcomers registry consecutively enrolling all patients aged ≥75 years eligible for percutaneous coronary intervention (PCI) with DES was carried out. Only one type of DES was implanted per protocol for each patient. Two groups were identified according to the type of implanted stent, i.e., SES and PES. The primary end point encompassed major adverse cardiac events (MACE), including death, myocardial infarction, and target lesion revascularization (TLR). The secondary end point encompassed the rate of definite/probable stent thrombosis and target vessel revascularization (TVR). From June 2004 to May 2008, 151 patients were enrolled. Among them, 112 (74.2%) received SES and 39 (25.8%) received PES. Baseline clinical characteristics were similar, while few angiographic features (ostial location, stent diameter, proximal reference vessel diameter) showed minor differences. At the median follow-up of 22.6 months, primary and secondary end points did not significantly differ in terms of MACE (SES 12.5% vs PES 20.5%, P = 0.3), death (SES 5.4% vs PES 7.7%, P = 0.7), myocardial infarction (SES 4.5% vs PES 10.3%, P = 0.2), TLR (SES 2.7% vs PES 2.6%, P = 1.0), stent thrombosis (SES 1.8% vs PES 5.1%, P = 0.3), and TVR (SES 1.8% vs PES 0%, P = 0.6). In this real-world population of elderly patients treated by DES–PCI for CAD, the overall efficacy and safety have been excellent in both DES, and the choice between SES and PES did not influence the clinical outcome.  相似文献   
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