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31.
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BACKGROUND: Chemokines and their receptors are important mediators of leucocyte trafficking and are suggested to be critical for establishment of inflammatory autoimmune processes. CC chemokine receptor 5 (CCR5) is expressed preferentially by CD4+ T cells. We hypothesised that the CCR5delta(Delta)32 genotype, which impairs surface expression of CCR5 in heterozygotes and is linked to a functional polymorphism of CD45RA expressed on suppressor-inducer-like 'naive' CD4+ T cells, may modulate the inflammatory process in primary biliary cirrhosis (PBC). METHODS: CCR5Delta32 polymorphism was determined by PCR in 226 Caucasian PBC patients and 197 racially matched controls from two geographical areas, Newcastle, UK and Padua, Italy. (UK: 144 PBC, 105 controls, Italy: 82 PBC, 92 controls). RESULTS: When the two series were analysed separately, there were no significant differences in the genotype distribution comparing patients and controls (UK: wt/wt 72% vs 76%; wt/Delta32 28% vs 22%; Delta32/Delta32 0% vs 2%, P=0.24; Italy: wt/wt 72% vs 82%; wt/Delta32 27% vs 17%; Delta32/Delta32 0% vs 1%, P=0.14). However, when the data for the two series were pooled and reanalysed, we found an increase in the CCR5Delta32 mutation in PBC patients vs controls (28% vs 21%, OR=1.43, P=0.03), but there was no evidence that this Delta32 polymorphism is associated with less severe disease. CONCLUSIONS: Although this two-centre genetic association study is large compared with others performed in PBC, taken separately, each geographically based cohort of patients and controls is underpowered to detect a small effect of this functional polymorphism. This emphasises the need for far larger case-control collections to address which polymorphic markers or haplotypes might modify the pathogenesis and clinical course of PBC. We propose that multi-centre collaboration on an international scale in 'orphan' complex liver diseases such as (PBC) is supported by the International Association for the Study of the Liver and promoted via their journal with development of a brief format for web-based publication of studies.  相似文献   
33.
A collection of 3069 human sera collected in the area of the municipality of Modena, Emilia Romagna, Italy, was retrospectively investigated for specific antibodies against Usutu (USUV) and West Nile viruses (WNV). All the samples resulting positive using a preliminary screening test were analyzed with the plaque reduction neutralization test. Overall, 24 sera were confirmed as positive for USUV (0.78%) and 13 for WNV (0.42%). The results suggest that in 2012, USUV was circulating more than WNV in North‐eastern Italy.  相似文献   
34.
Nitric oxide is thought to play an importantrole in modulating the inflammatory process. Recently anincrease in the inducible form of nitric oxide synthase(iNOS) has been found in the rat trinitrobenzene sulfonic acid model of experimental colitis,and inhibition of nitric oxide synthase activityresulted in an amelioration of tissue injury. The aim ofour study was to evaluate in vivo intracolonic release of nitric oxide in this model of colitis.Experimental colitis was induced in male Sprague-Dawleyrats by a single intracolonic administration oftrinitrobenzene sulfonic acid. Nitrite levels weredetermined in rectal dialysates by HPLC. The tissuemyeloperoxidase and iNOS and the luminal leukotrieneB4 were also measured. Nitrite levels weresignificantly increased in rectal dialysates duringcolitis and correlated significantly with tissue myeloperoxidase andiNOS activity. The correlation between nitrite dialysatelevels and wall iNOS activity confirms that nitrite indialysates is produced by inflammatory cells and not by colonic bacterial flora.Determination of nitrite levels in rectal dialysatesseems a valuable method to monitor colonic inflammationin rat trinitrobenzene sulfonic acid colitis.  相似文献   
35.
BACKGROUND & AIMS: We have recently documented the efficacy of a highly concentrated probiotic preparation (VSL#3) in the prevention of flare-up in patients with chronic pouchitis. The aim of this study was to compare probiotic therapy with VSL#3 versus placebo in the ability to prevent the onset of acute pouchitis during the first year after ileal pouch-anal anastomosis. METHODS: Forty consecutive patients who underwent ileal pouch-anal anastomosis for ulcerative colitis were randomized to receive either VSL#3 (1 packet containing 900 billion bacteria/day) (n = 20) or an identical placebo (n = 20) immediately after ileostomy closure for 1 year. The patients were assessed clinically, endoscopically, and histologically after 1, 3, 6, 9, and 12 months. Health-related quality of life was assessed using the Inflammatory Bowel Disease Questionnaire. RESULTS: Two of the 20 patients (10%) treated with VSL#3 had an episode of acute pouchitis compared with 8 of the 20 patients (40%) treated with placebo (log-rank test, z = 2.273; P < 0.05). Treatment with VSL#3 determined a significant improvement in Inflammatory Bowel Disease Questionnaire score, whereas this was not the case with placebo. CONCLUSIONS: Treatment with VSL#3 is effective in the prevention of the onset of acute pouchitis and improves quality of life of patients with ileal pouch-anal anastomosis.  相似文献   
36.
An increased prevalence of liver diseases such as hepatitis C and nonalcoholic fatty liver results in an augmented incidence of the most common form of liver cancer, hepatocellular carcinoma (HCC). HCC is most often found in the cirrhotic liver and it can therefore be challenging to rely on anatomical information alone when diagnosing HCC. Valuable information on specific cellular metabolism can be obtained with high sensitivity thanks to an emerging magnetic resonance (MR) technique that uses 13C labeled hyperpolarized molecules. Our interest was to explore potential new high contrast metabolic markers of HCC using hyperpolarized 13C‐MR. This work led to the identification of a class of substrates, low molecular weight ethyl‐esters, which showed high specificity for carboxyl esterases and proved in many cases to possess good properties for signal enhancement. In particular, hyperpolarized [1,3‐13C2]ethyl acetoacetate (EAA) was shown to provide a metabolic fingerprint of HCC. Using this substrate a liver cancer implanted in rats was diagnosed as a consequence of an ~4 times higher metabolic substrate‐to‐product ratio than in the surrounding healthy tissue, (p = 0.009). Unregulated cellular uptake as well as cosubstrate independent enzymatic conversion of EAA, made this substrate highly useful as a hyperpolarized 13C‐MR marker. This could be appreciated by the signal‐to‐noise (SNR) obtained from EAA, which was comparable to the SNR reported in a literature liver cancer study with state‐of‐the‐art hyperpolarized substrate, [1‐13C]pyruvate. Also, the contrast‐to‐noise (CNR) in the EAA based metabolic ratio images was significantly improved compared with the CNR in equivalent images reported using [1‐13C]pyruvate.  相似文献   
37.
38.
BACKGROUND: The benefit of neoadjuvant chemoradiotherapy in oesophageal cancer has been extensively studied but data on survival are still equivocal. OBJECTIVE: To assess the effectiveness of chemoradiotherapy followed by surgery in the reduction of mortality in patients with resectable oesophageal cancer. METHODS: Computerised bibliographic searches of MEDLINE and CANCERLIT (1970-2002) were supplemented with hand searches of reference lists. STUDY SELECTION: Studies were included if they were randomised controlled trials (RCTs) comparing preoperative chemoradiotherapy plus surgery with surgery alone, and if they included patients with resectable histologically proven oesophageal cancer without metastatic disease. Six eligible RCTs were identified and included in the meta-analysis. DATA EXTRACTION: Data on study populations, interventions, and outcomes were extracted from each RCT according to the intention to treat method by three independent observers and combined using the DerSimonian and Laird method. RESULTS: Chemoradiotherapy plus surgery compared with surgery alone significantly reduced the three year mortality rate (odds ratio (OR) 0.53 (95% confidence interval (CI) 0.31-0.93); p = 0.03) (number needed to treat = 10). Pathological examination showed that preoperative chemoradiotherapy downstaged the tumour (that is, less advanced stage at pathological examination at the time of surgery) compared with surgery alone (OR 0.43 (95% CI 0.26-0.72); p = 0.001). The risk for postoperative mortality was higher in the chemoradiotherapy plus surgery group (OR 2.10 (95% CI 1.18-3.73); p = 0.01). CONCLUSIONS: In patients with resectable oesophageal cancer, chemoradiotherapy plus surgery significantly reduces three year mortality compared with surgery alone. However, postoperative mortality was significantly increased by neoadjuvant chemoradiotherapy. Further large scale multicentre RCTs may prove useful to substantiate the benefit on overall survival.  相似文献   
39.
In a prospective study, we examined the impact of arterial hypervascularity, as established by the European Association for the Study of the Liver (EASL) recommendations, as a criterion for characterizing small (1-3 cm) nodules in cirrhosis. A total of 72 nodules (1-2 cm, n = 41; 2.1-3 cm, n = 31) detected by ultrasonography in 59 patients with cirrhosis were included in the study. When coincidental arterial hypervascularity was detected at contrast perfusional ultrasonography and helical computed tomography, the lesion was considered to be hepatocellular carcinoma (HCC) according to EASL criteria. When one or both techniques showed negative results, ultrasound-guided biopsy was performed. In cases with negative results for malignancy or high-grade dysplasia, biopsy was repeated when an increase in size was detected at the 3-month follow-up examination. Coincidental hypervascularity was found in 44 of 72 nodules (61%; 44% of 1-2-cm nodules and 84% of 2-3-cm nodules). Fourteen nodules (19.4%) had negative results with both techniques (hypovascular nodules). Biopsy showed HCC in 5 hypovascular nodules and in 11 of 14 nodules with hypervascularity using only one technique. All nodules larger than 2 cm finally resulted to be HCC. Not satisfying the EASL imaging criteria for diagnosis were 38% of HCCs 1 to 2 cm (17% hypovascular) and 16% of those 2 to 3 cm (none hypovascular). In conclusion, the noninvasive EASL criteria for diagnosis of HCC are satisfied in only 61% of small nodules in cirrhosis; thus, biopsy frequently is required in this setting. Relying on imaging techniques in nodules of 1 to 2 cm would miss the diagnosis of HCC in up to 38% of cases. Any nodule larger than 2 cm should be regarded as highly suspicious for HCC.  相似文献   
40.
BACKGROUND: This study aimed at investigating the relative powers of the quantitative evaluation of functional mitral regurgitation (FMR) and ejection fraction (EF) in predicting the clinical changes and prognosis of dilated cardiomyopathy (DCM) with severe systolic dysfunction. METHODS: A total of 81 patients with DCM, EF < 0.40 and at least mild FMR were prospectively evaluated during a mean follow-up of 24 +/- 7 months. Twenty cardiac deaths were recorded. At the time of enrolment all patients underwent echocardiographic evaluation of the effective regurgitant orifice area (ERO), EF, left atrial area, and tenting area. In 42/81 patients, the data obtained at enrolment were compared to those measured at a mean follow-up of 10 +/- 2 months. A multivariate analysis was performed to determine the best predictor of NYHA class and mortality. RESULTS: There was a correlation between the NYHA class and the ERO (chi2 = 26.1, p = 0.0001) but not with EF (chi2 = 4.3, p = 0.22) and at multivariate analysis, the ERO was found to be the main determinant of the NYHA class (r = 0.64, standard error 0.6, p = 0.0001). The NYHA class remained unchanged or improved in 28/42 (67%) and deteriorated in 14/42 (33%) patients. In the first group, the ERO increased from 22.3 +/- 10 to 30.2 +/- 16.4 mm2 (p = 0.05) and the tenting area from 5.8 +/- 1.8 to 6.8 +/- 1.8 cm2 (p = 0.001); in the second group, the ERO increased from 25.1 +/- 5.6 to 39.0 +/- 14.5 mm2 (p = 0.04) and the tenting area from 5.9 +/- 2.1 to 7.6 +/- 1.8 cm2 (p = 0.0001), in both groups without significant changes in EF. The mortality was 8.1% in patients with an ERO < 21 mm2, 30.3% in patients with an ERO of 21-30 mm2, and 50% in those with an ERO > 30 mm2. The EF was similar in the three subgroups. At Cox multivariate analysis the best predictors of mortality were the ERO (chi2 = 13.83, p = 0.0001), EF (chi2 = 5.48, p = 0.019), and left atrial area (chi2 = 4.52, p = 0.04). CONCLUSIONS: FMR in DCM well correlated with the clinical status of the patients and its worsening was suggestive of progression of the disease. The ERO was found to be the best predictor of the NYHA class and mortality.  相似文献   
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