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81.

Background

Capsule endoscopy has been proposed as an alternative to fibreoptic endoscopy for oesophageal varices evaluation in cirrhotics. However, it shows only moderate sensitivity compared to fibreoptic endoscopy.

Aim

To compare post-meal capsule endoscopy to fibreoptic endoscopy, based on the hypothesis that meal-induced increase of portal pressure can enhance its sensitivity.

Methods

Twenty-five patients were submitted to fibreoptic endoscopy and, after a standard meal, capsule endoscopy.

Results

Post-meal capsule endoscopy detected varices in the 18 patients in whom fibreoptic endoscopy detected varices plus 3 more subjects (sensitivity 100%, specificity 70%); large varices in the 4 patients in whom fibreoptic endoscopy graded varices as large, plus 5 more subjects; red markers in the 5 patients in whom fibreoptic endoscopy detected red markers, plus 3 more subjects. High-risk varices were identified in 11 patients by post-meal capsule endoscopy and in 10 by fibreoptic endoscopy (sensitivity 100%, specificity 93.8%).

Conclusions

Post-meal capsule endoscopy identified more varices, large varices and red markers than fibreoptic endoscopy. The two methods detected similar proportions of high-risk varices. These data suggest that a standard meal can enhance the sensitivity of capsule endoscopy in the detection and grading of oesophageal varices in cirrhotics.  相似文献   
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CD4+CD25+Foxp3+ regulatory T cells (Treg) specialize in suppressing immune responses. In this study, 47 consecutive colon cancer patients were subjected to circulating Treg frequency assessment by flow cytometry before and after cancer resection. Thirty-two healthy subjects served as controls. Circulating Treg frequencies were significantly higher in colon cancer patients with respect to healthy controls. When patients were subgrouped according to Dukes stages, a linear relationship was observed between Dukes stages and Treg frequencies. In radically resected patients, Treg frequencies were shown to have significantly dropped down. Patients with advanced colon cancer were more likely to have significantly higher proportions of circulating Treg frequencies than Dukes A and B patients when compared to healthy subjects. Of note, nonradically resected patients were found to display reductions in—but not normalization of—Treg frequencies. These results suggest that cancer itself may be able to drive Treg recruitment as a strategy of immunoevasion.  相似文献   
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In chronic lymphocytic leukaemia (CLL), caution is warranted regarding the clinical implications of immunoglobulin variable heavy chain region (IGHV) rearrangements with a ‘borderline’ (BL) percentage of mutations (i.e. 97–97·9% IGHV identity). We analysed the IGHV mutational status in 759 untreated CLL patients (cohort 1). BL-CLL (n = 36, 5%) showed a time to first treatment (TFT) similar to that of M-CLL (n = 338) and significantly longer than that of UM-CLL (n = 385), despite the enrichment in subset #2 cases. In fact, CLLs belonging to subset #2 (n = 15/759, 2%) were significantly more frequent among BL-CLLs (n = 5/36, 14%), with a brief TFT. TFT of BL-CLL remained comparable to that of M-CLL also considering the 327 CLL patients evaluated at diagnosis. These findings were then validated in an independent cohort 2 of 759 newly diagnosed CLL patients (BL-CLL: n = 11, 1·4%) and in all newly diagnosed patients from cohorts 1 and 2 (n = 1 086, 84% stage A; BL-CLL: n = 47, 4·3%). BL-CLL at diagnosis showed a biological profile comparable to that of M-CLL with a low frequency of unfavourable prognostic markers, except for a significant enrichment in subset #2. Our data suggest that the prognosis of BL-CLL is good and similar to that of M-CLL, with the exception of subset #2 cases.  相似文献   
87.
Vitamin E affects cell death in adult rat dentate gyrus   总被引:1,自引:0,他引:1  
We have previously reported the presence of dying cells in the granule cell layer (GCL) of adult rat dentate gyrus (DG), where neurogenesis occurs. In particular, we found that cell death in the GCL increased in vitamin E deficiency and decreased in vitamin E supplementation. These findings were regarded as related to changes in neurogenesis rate, which in turn was influenced by vitamin E availability; a neuroprotective effect of vitamin E on cell death was also proposed. In order to verify this latter hypothesis, we have studied cell death in all layers of DG in vitamin E-deficient and vitamin E-supplemented rats and in control rats at different ages, using TUNEL and nick translation techniques. The phenotype of TUNEL-positive cells was characterized and the existence of dying BrdU-positive cells was investigated. Dying cells with neuronal phenotype were observed throughout the DG in all experimental groups. The number of TUNEL-positive cells decreased from juvenile to adult age. A higher number of TUNEL-positive cells in vitamin E-deficient rats and a lower number in vitamin E-supplemented rats, with respect to age-matched controls, were found; moreover, in these groups, TUNEL-positive cells had a different percentage distribution in the different layers of the DG. Our results confirm the occurrence of cell death in DG, demonstrate that cell death affects neuronal cells and support the hypothesis that the effect of vitamin E on cell death is not related to neurogenesis.  相似文献   
88.
Skin rejection remains a major hurdle in skin reconstructive transplantation surgery. In fact, 85% of the grafted patients experience at least one episode of acute skin rejection in the first year. It has been observed that Sertoli cells (SC), when co-transplanted with allo- or xenogeneic cell/tissues, can induce graft acceptance in the absence of systemic immunosuppression. A method aimed at significantly prolonging skin allografts in rats transplanted with barium alginate-based microencapsulated xenogeneic porcine SC (SC-MCs) is described. Results demonstrated that intraperitoneal (IP) transplantation of SC-MCs with high cellular viability and function can significantly prolong allogeneic skin grafts when compared to transplantation controls receiving only empty alginate capsules (E-MCs). Lymphocytic infiltration at the skin graft site was not observed in 80% of the SC-MCs transplanted rats and these recipient animals showed a significant increased expression of T regulatory (Tregs) cells when compared to E-MCs transplantation controls. The findings of this report further substantiate the positive therapeutic effects of SC on transplantation technology mediated by Sertoli cell-induced alterations of the host's immune system and indicate new perspectives and new strategies for successful skin tissue allografts.  相似文献   
89.
Endstage liver disease caused by chronic hepatitis C virus (HCV) infection is the leading indication for liver transplantation in the Western world. However, immediate reinfection of the grafted donor liver by circulating virus is inevitable and liver disease progresses much faster than the original disease. Standard antiviral therapy is not well tolerated and usually ineffective in liver transplant patients, whereas anti-HCV immunotherapy is hampered by the extreme genetic diversity of the virus and its ability to spread by way of cell-cell contacts. We generated a human monoclonal antibody against scavenger receptor class B type I (SR-BI), monoclonal antibody (mAb)16-71, which can efficiently prevent infection of Huh-7.5 hepatoma cells and primary hepatocytes by cell-culture-derived HCV (HCVcc). Using an Huh7.5 coculture system we demonstrated that mAb16-71 interferes with direct cell-to-cell transmission of HCV. Finally we evaluated the in vivo efficacy of mAb16-71 in "human liver urokinase-type plasminogen activator, severe combined immune deficiency (uPA-SCID) mice" (chimeric mice). A 2-week anti-SR-BI therapy that was initiated 1 day before viral inoculation completely protected all chimeric mice from infection with serum-derived HCV of different genotypes. Moreover, a 9-day postexposure therapy that was initiated 3 days after viral inoculation (when viremia was already observed in the animals) suppressed the rapid viral spread observed in untreated control animals. After cessation of anti-SR-BI-specific antibody therapy, a rise of the viral load was observed. CONCLUSION: Using in vitro cell culture and human liver-chimeric mouse models, we show that a human mAb targeting the HCV coreceptor SR-BI completely prevents infection and intrahepatic spread of multiple HCV genotypes. This strategy may be an efficacious way to prevent infection of allografts following liver transplantation in chronic HCV patients, and may even hold promise for the prevention of virus rebound during or following antiviral therapy.  相似文献   
90.
3-Iodothyronamine (T1AM) is a novel chemical messenger, structurally related to thyroid hormone, able to interact with G protein-coupled receptors known as trace amine-associated receptors (TAARs). Little is known about the physiological role of T1AM. In this prospective, we synthesized [125I]-T1AM and explored its distribution in mouse after injecting in the tail vein at a physiological concentration (0.3?nM). The expression of the nine TAAR subtypes was evaluated by quantitative real-time PCR. [125I]-T1AM was taken up by each organ. A significant increase in tissue vs blood concentration occurred in gallbladder, stomach, intestine, liver, and kidney. Tissue radioactivity decreased exponentially over time, consistent with biliary and urinary excretion, and after 24?h, 75% of the residual radioactivity was detected in liver, muscle, and adipose tissue. TAARs were expressed only at trace amounts in most of the tissues, the exceptions being TAAR1 in stomach and testis and TAAR8 in intestine, spleen, and testis. Thus, while T1AM has a systemic distribution, TAARs are only expressed in certain tissues suggesting that other high-affinity molecular targets besides TAARs exist.  相似文献   
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