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41.

Background

Rapid Urease Test (RUT) is a simple, cheap and relatively fast method for diagnosing Helicobacter pylori infection. It is therefore the preferred method used for patients undergoing gastroscopy. Most kits require 24 h to give results. The new Ultra-Rapid Urease Test (URUT) kit by Biohit® requires less than 1 h.

Objective

To determine URUT's diagnostic accuracy.

Method

Prospective, blind, multi-centre study involving dyspeptic patients. One corpus biopsy and three antral biopsies were obtained during gastroscopy for standard histological analysis, RUT and URUT. The URUT result was checked after 1 min, 5 min, 30 min and 60 min and the RUT was checked over the course of 24 h. Histology was used as the gold standard test.

Results

144 patients were included, 68% female, with a mean age of 49 years old; 50% were H. pylori positive. RUT and URUT diagnoses were correct in 85.9% and 90% of the cases, respectively. The mean waiting time for a positive RUT result was 6 h. The sensitivity, specificity, and positive and negative predictive values for RUT were, respectively, 82%, 90%, 89% and 84%. The URUT's results were similar (85%, 94%, 94% and 87%). These figures improved when patients taking PPIs were excluded (RUT: 86%, 91%, 93% and 83%; URUT: 91%, 94%, 96% and 89%). No statistically significant differences were found when comparing RUT and URUT distributions of correct diagnoses (McNemar's Test, p = 0.3) but there was a tendency towards better results with the URUT.

Conclusion

The URUT is equivalent to (or slightly better than) the traditional RUT in diagnosing H. pylori infection, and provides results in less than an hour.  相似文献   
42.
Familial Mediterranean fever (FMF) is an autosomal recessive disease characterized by recurring short attacks of fever and serositis. Secondary AA amyloidosis is the worst complication of the disease and often determines the prognosis. The MEFV gene, on chromosome 16p13.3, is responsible for the disease and around 30 mutations have been reported to date. Colchicine is the standard FMF treatment today, and prevents both attacks and amyloid deposition in 95% of patients. Here we describe a three-generation Spanish kindred with five family members affected by a severe periodic inflammatory disorder associated with renal AA amyloidosis and colchicine unresponsiveness. Clinical diagnosis of definite FMF disease was made based on the Tel-Hashomer criteria set. Genetic analyses revealed that all subjects were heterozygous for the new H478Y MEFV variant, segregating with the disease. In addition, mutations in the TNFRSF1A and CIAS1/PYPAF1/NALP3 genes, related to the dominantly inherited autoinflammatory periodic syndromes, were ruled out. However, the dominant inheritance of the disease, the long fever episodes with a predominant joint involvement, and the resistance to colchicine in these patients raise the question of whether the periodic syndrome seen in this kindred is a true FMF disease with unusual manifestations or rather another MEFV-associated periodic syndrome. We conclude that the new H478Y MEFV mutation is the dominant pathological variant causing the inflammatory periodic syndrome in this kindred and that full-length analyses of the MEFV gene are needed to obtain an adequate diagnosis of patients with clinical suspicion of a hereditary periodic fever syndrome, especially those from non-ancestral populations.  相似文献   
43.
OBJECTIVES: To analyze the dynamics of both HIV-1-specific CD4 and CD8 T-cell responses during structured treatment interruptions (STIs) in chronically HIV-1-infected (CHI) patients and to correlate them with the viral set point achieved. METHODS: Forty-five early-stage CHI patients who were on highly active antiretroviral therapy (HAART) for at least 1 year and underwent STI were included. Plasma viral load (VL), peripheral blood mononuclear cell (PBMC) lymphoproliferative (LPR) response to HIV p24 protein, and HIV-1 epitope-specific interferon-gammarelease from CD8 T cells were measured over a minimum study period of 2 years. RESULTS: VL set point during final STI was both significantly lower than, and positively correlated to, baseline VL (P < 0.0001: mean VL reduction 0.77 log10, and r = 0.42, P = 0.004, respectively). CD4 LPRs to p24 increased significantly (P = 0.001) between day 0 of the first STI cycle and 4th STI but decreased thereafter. VL set point during final STI was significantly and negatively correlated with LPRs to p24 at both 2nd STI and 4th STI. Nevertheless, at week 52, 12 weeks after the end of the last STI, LPRs were weak and transient in all patients and were not correlated with VL set point. Moreover, the magnitude and breadth of HIV-1-specific CD8 T-cell responses increased significantly (P < 0.0001) between day 0 and week 52. The largest increases occurred during the final STI. Even though VL reached set point by week 12 of the final STI, HIV-1-specific CD8 T-cell responses did not stabilize but rather increased until the end of the follow-up and did not correlate with plasma VL (r = 0.01, P = 0.88). CONCLUSIONS: STIs do not lead to control of viral replication in CHI patients, probably due to the fact that boosted CTL responses lack strong and durable helper T-cell responses. To reset the VL set point, new approaches that effectively augment and preserve helper T-cell responses should be investigated.  相似文献   
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46.
AIM: To evaluate the efficacy of 5 compared to :tO granulocyteaphaeresis sessions in patients with active steroid-dependent ulcerative colitis.
METHODS: In this pilot, prospective, multicenter randomized trial, 20 patients with moderately active steroid-dependent ulcerative colitis were randomized to 5 or 10 granulocyteaphaeresis sessions. The primary objective was clinical remission at wk 17. Secondary measures included endoscopic remission and steroid consumption.
RESULTS: Nine patients were randomized to 5 granulocyteaphaeresis sessions (group 1) and 11 patients to 10 granulocyteaphaeresis sessions (group 2). At wk 17, 37.5% of patients in group 1 and 45.45% of patients in group 2 were in clinical remission. Clinical remission was accompanied by endoscopic remission in all cases. Eighty-six percent of patients achieving remission were steroid-free at wk 17. Daily steroid requirements were significantly lower in group 2. Eighty-nine per cent of patients remained in remission during a one year follow-up. One serious adverse event, not related to the study therapy, was reported.
CONCLUSION: Granulocyteaphaeresis is safe and effective for the treatment of steroid-dependent ulcerative colitis. In this population, increasing the number of aphaeresis sessions is not associated with higher remission rates, but affords a significant steroid-sparing effect.  相似文献   
47.
Purpose Patients with colorectal cancer have a high risk of developing metachronous neoplasms. Identification of predictive factors associated with such conditions would allow individualized follow-up strategies in these patients. This study was designed to identify individual and familial factors associated with the development of metachronous colorectal neoplasms in patients with colorectal cancer. Methods In the context of a prospective, multicenter, general population-based study—the EPICOLON project—all patients with colorectal cancer attended in ten Spanish hospitals during a one-year period were included. Patients with familial adenomatous polyposis or inflammatory bowel disease were excluded. All patients were monitored by colonoscopy within two years of the diagnoses. Demographic, clinical, pathologic, molecular (microsatellite instability status and immunohistochemistry for MSH2 and MLH1), and familial characteristics (fulfillment of Amsterdam I or II criteria, and revised Bethesda guidelines) were analyzed. Results A total of 353 patients were included in the study. At two years of follow-up, colonoscopy revealed the presence of adenomas in 89 (25 percent) patients and colorectal cancer in 14 (3.9 percent) patients, in 7 cases restricted to anastomosis. Univariate analysis demonstrated that development of metachronous neoplasm (adenoma or colorectal cancer) was associated with personal history of previous colorectal cancer (odds ratio, 5.58; 95 percent confidence interval, 1.01–31.01), and presence of previous or synchronous adenomas (odds ratio, 1.77; 95 percent confidence interval, 1.21–3.17). Although nonstatistical significance was achieved, metachronisms were associated with gender (P < 0.09) and differentiation degree (P < 0.08). Multivariate analysis identified previous or synchronous adenomas (odds ratio, 1.98; 95 percent confidence interval, 1.16–3.38) as independent predictive factor. Neither presence of tumor DNA microsatellite instability nor family history correlated with the presence of metachronous neoplasms. Conclusions Patients with previous or synchronous colorectal adenoma have an increased risk of developing metachronous colorectal neoplasms. Accordingly, this subgroup of patients may benefit from specific surveillance strategies. Supported by grants from the Red Nacional de Investigación en Hepatología y Gastroenterología (Instituto de Salud Carlos III, C03/02) and from Fondo de Investigaciones Sanitarias (FIS PI061384). Xavier Llor is a recipient of a Ramon y Cajal grant form Ministerio de Ciencia y Tecnología of the Spanish government Presented at the meeting of the United European Gastroenterology, Copenhagen, Denmark, October 15 to 19, 2005.  相似文献   
48.
STUDY OBJECTIVES: To assess whether the measurement of breathing reduction during obstructive sleep events depends on using the flow or the volume signals recorded with a pneumotachograph. DESIGN: Prospective observational study. SETTING: Sleep laboratory in a University Hospital. PATIENTS OR PARTICIPANTS: Data from 10 male patients with sleep apnea (54 +/- 11 years, apnea-hypopnea index: 43 +/- 21 events/hour, body mass index: 30 +/- 2 kg/m2). INTERVENTIONS: Slow modification of continuous positive airway pressure was performed during full-polysomnography continuous positive airway pressure titration. MEASUREMENTS AND RESULTS: Air flow was measured by a pneumotachograph, and volume was computed by numerical integration. Obstructive events of different magnitude were selected. In 500 breathing cycles analyzed, the reduction in tidal volume was greater than the reduction in the flow amplitude: mean difference of 0.091 (i.e., 9.1% amplitude) and limits of agreement of 0.095 and -0.277 (i.e., 9.5% and -27.7% amplitude). In 14% of the cycles, the reduction in flow was < 50%, whereas the reduction in volume was > 50%, resulting in discordant event classification. CONCLUSIONS: The quantification of breathing reduction depends on whether the flow or the volume signal is used to assess breathing during sleep.  相似文献   
49.
Hepatitis B virus infection (HBV) with undetectable levels of HBsAg, has been named occult HBV infection and observed in immunosuppressed patients. The aim of this study was to determine the frequency of occult HBV infection in patients with HIV from the West of México, using a combination of serological markers and nPCR. Thirty eight HIV/AIDS patients, 32 men (84.2%) and 6 (5.8%) women, without liver damage related symptoms were studied. HBV coinfection was observed in 10 (26.3%) patients; while only 3 (7.9%) of them were positive to HBsAg. Thus, 7 (18.4%) occult HBV infected patients could be assessed in this population. One (10%) patient with occult HBV infection was positive to anti-HBs, in spite of the reinfection protection attributed to this serological marker. Anti-HBc was detected only in 2 (20%) patients with occult HBV infection. No significant association could be established between occult HBV infection and CD+4 cell count, biochemical, clinical parameters, AIDS stage, or any other risk factor. This study suggest that determination of HBV DNA utilizing highly sensitive techniques, as nPCR, should be performed to detect occult HBV infection, even in the absence of anti-HBc in HIV/ AIDS patients, in order to have a reliable diagnosis, prevent HBV dissemination and acute exacerbation of chronic hepatitis B or even fulminant hepatitis. To our knowledge this is the first study of occult HBV infection in Mexican patients with HIV. However, further studies are necessary in order to determine HBV genotypes and its relationship with evolution and clinical manifestation of the disease.  相似文献   
50.
It has been suggested that oxidative stress is a feature of aging. The goal of the present study was to assess the oxidant effects related to aging and the protective role of exogenous melatonin in senescence-accelerated mice (SAMP8). Two groups of SAMP8 mice (males and females) were compared with their respective control groups of SAMR1 mice (senescence-resistant inbred strain) to determine their oxidative status without melatonin treatment. Four other groups of the same characteristics were treated with melatonin (10 mg/kg/day) in their drinking water. The melatonin concentration in the feeding bottles was titrated according to water consumption and body weight (i.e. 0.06 mg/mL for 30 g of body weight and 5 mL/day of water consumption). The treatment began when animals were 1-month old and continued for 9 months. When mice were 10-month old, they were anesthetized and blood was obtained. Plasma and erythrocytes were processed to examine oxidative stress markers: reduced glutathione (GSH), oxidized glutathione (GSSG), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), glutathione reductase (GR), glutathione S-transferase (GST), thiobarbituric acid reactive substances (TBARS), and hemolysis. The results showed greater oxidative stress in SAMP8 than in SAMR1, largely because of a decrease in GSH levels and to an increase in GSSG and TBARS with the subsequent induction of the antioxidant enzymes GPX and GR. Melatonin, as an antioxidant molecule, improved the glutathione-related parameters, prevented the induction of GPX in senescent groups, and promoted a decrease in SOD and TBARS in almost all the groups.  相似文献   
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