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51.

Introduction

Intraluminal therapy used in the gastrointestinal (GI) tract was first shown for anastomotic leaks after rectal resection. Since a few years vacuum sponge therapy is increasingly being recognized as a new promising method for repairing upper GI defects of different etiology. The principles of vacuum-assisted closure (VAC) therapy remain the same no matter of localization: Continuous or intermittent suction and drainage decrease bacterial contamination, secretion, and local edema. At the same time, perfusion and granulation is promoted. However, data for endoscopic vacuum therapy (EVT) of the upper intestinal tract are still scarce and consist of only a few case reports and small series with low number of patients.

Objectives

Here, we present a single center experience of EVT for substantial wall defects in the upper GI tract.

Methods

Retrospective single-center analysis of EVT for various defects of the upper GI tract over a time period of 4 years (2011–2015) with a mean follow-up of 17 (2–45) months was used. If necessary, initial endoscopic sponge placement was performed in combination with open surgical revision.

Results

In total, 126 polyurethane sponges were placed in upper gastrointestinal defects of 21 patients with a median age of 72 years (range, 49–80). Most frequent indication for EVT was anastomotic leakage after esophageal or gastric resection (n?=?11) and iatrogenic esophageal perforation (n?=?8). The median number of sponge insertions was five (range, 1–14) with a mean changing interval of 3 days (range, 2–4). Median time of therapy was 15 days (range, 3–46). EVT in combination with surgery took place in nine of 21 patients (43 %). A successful vacuum therapy for upper intestinal defects with local control of the septic focus was achieved in 19 of 21 patients (90.5 %).

Conclusion

EVT is a promising approach for postoperative, iatrogenic, or spontaneous lesions of the upper GI tract. In this series, EVT was combined with operative revision in a relevant proportion of patients.
  相似文献   
52.
We have investigated the localization of thrombospondin (TSP), fibrinogen, fibronectin, and von Willebrand factor in human platelets by transmission electron microscopy of antibody-stained ultrathin frozen sections. In negatively stained thin sections, alpha granules were identified on the basis of their smooth, roughly spherical shape, size, single limiting electron-lucent 100 A membrane, and frequent presence of electron-dense nucleoid. In contrast, mitochondria exhibited characteristic double membranes and cristae. Sections were separately stained with affinity-purified polyclonal antibodies to these proteins as well as with three monoclonal anti-TSP antibodies. Antibody specificity was documented in radioimmunoassays, by immunofluorescent cross-blocking, and by staining of bands of appropriate mobility in Western blots of whole platelets. Bound antibody was visualized using a 5-nm colloidal gold-avidin conjugate. In resting cells, staining of virtually all alpha granules was observed for all four proteins. In contrast, consistent staining was absent from other organelles, including plasma membranes, mitochondria, and vacuolar structures that may represent the open canalicular system.  相似文献   
53.
Plow  EF; Marguerie  GA; Ginsberg  MH 《Blood》1985,66(1):26-32
Plasma fibronectin binds in a specific and saturable manner to thrombin- stimulated platelets. gamma-Thrombin stimulated 80% as much fibronectin binding to platelets as alpha-thrombin with conversion of less than or equal to 1% of platelet fibrinogen to fibrin. Afibrinogenemic and normal platelets bound similar quantities of fibronectin in the presence of calcium or magnesium-ethylene glycol tetra-acetic acid (EGTA). These observations indicate that fibronectin can interact with platelets without involvement of fibrin or fibrinogen. Nevertheless, two different effects of fibrin(ogen) on fibronectin binding were observed. First, exogenous fibrinogen inhibited fibronectin binding to thrombin-stimulated platelets. This inhibition was unidirectional, as fibronectin did not inhibit fibrinogen binding to ADP or thrombin- stimulated cells. Second, formaldehyde-fixed cells with surface- associated fibrin bound significant quantities of fibronectin. This interaction required calcium and did not occur on fixed cells with or without surface-bound fibrinogen. A portion of the ligand bound to fixed cells with surface-associated fibrin was modified to form a derivative with a molecular weight identical to that of the fibronectin subunit cross-linked to the alpha-chain of fibrin. This high mol wt derivative was also observed to a variable extent with living cells in the presence of magnesium or calcium but not in the presence of magnesium-EGTA. Thus, fibronectin binds to platelets by at least two mechanisms: (1) a fibrin(ogen)-independent pathway that requires divalent ions and is inhibited by exogenous fibrinogen; and (2) a fibrin-dependent pathway with an absolute calcium requirement. With nonaggregated, thrombin-stimulated platelets, the former pathway appears to predominate.  相似文献   
54.

Background

We examined the association of alcohol use disorders (AUD) with adherence to and health-related quality of life (HRQOL) outcomes of antiretroviral treatment (ART) for HIV/AIDS patients.

Methods

A cross-sectional multi-site survey was conducted in 468 drug users and 648 non-drug users (age: 35.4 ± 7.0 years; 63.8% male) in 3 epicentres of Vietnam. AUD, ART adherence, and HRQOL were measured using the Alcohol Use Disorders Identification Test - Consumption (AUDIT-C), the self-reported Visual Analogue Scale (VAS), and the World Health Organization Quality of Life instrument (WHOQOL-HIV BREF).

Results

35.0% of drug users were hazardous drinkers, compared to 25.9% of non-drug users. 22.3% of drug users engaged in binge drinking, and 25.9% reported suboptimal ART adherence. Adjusting for propensity scores of AUD, patients who had either at-risk or binge drinking behaviour were about twice as likely to be treatment non-adherent as those who did not have AUD. Hazardous drinkers reported small to medium decrements in the Performance, Physical, Social, Spirituality, and Environment quality of life domains. Binge drinkers had a slightly higher score in Social dimension.

Conclusion

AUD is prevalent and negatively affecting adherence to and HRQOL outcomes of ART services in injection-driven HIV epidemics. Screening and intervention are recommended for AUD, especially during the stable periods of ART. Other social and psychological interventions might also enhance patients’ responses to and outcomes of ART in Vietnam.  相似文献   
55.
Autosomal dominant gain of function mutations in the gene encoding PI3K p110δ were recently associated with a novel combined immune deficiency characterized by recurrent sinopulmonary infections, CD4 lymphopenia, reduced class-switched memory B cells, lymphadenopathy, CMV and/or EBV viremia and EBV-related lymphoma. A subset of affected patients also had elevated serum IgM. Here we describe three patients in two families who were diagnosed with HIGM at a young age and were recently found to carry heterozygous mutations in PIK3CD. These patients had an abnormal circulating B cell distribution featuring a preponderance of early transitional (T1) B cells and plasmablasts. When stimulated in vitro, PIK3CD mutated B cells were able to secrete class-switched immunoglobulins. This finding implies that the patients’ elevated serum IgM levels were unlikely a product of an intrinsic B cell functional inability to class switch. All three patients developed malignant lymphoproliferative syndromes that were not associated with EBV. Thus, we identified a novel subset of patients with PIK3CD mutations associated with HIGM, despite indications of preserved in vitro B cell class switch recombination, as well as susceptibility to non-EBV-associated malignancies.  相似文献   
56.
Recent studies indicate that the primary somatosensory cortex (S1) is active not only when touch is physically perceived but also when it is merely observed to be experienced by another person. This social responsivity of S1 has important implications for our understanding of S1 functioning. However, S1 activity during touch observation has not been characterized in great detail to date. We focused on two features of the S1 functional architecture during touch observation, namely the topographical arrangement of index and middle finger receptive fields (RFs), and their dynamic shrinkage during concurrent activation. Both features have important implications for human behavior. We conducted two fMRI studies at 7 T, one where touch was physically perceived, and one where touch was observed. In the two experiments, participants either had their index finger and/or middle finger stimulated using paintbrushes, or just observed similar touch events on video. Our data show that observing and physically experiencing touch elicits overlapping activity changes in S1. In addition, observing touch to the index finger or the middle finger alone evoked topographically arranged activation foci in S1. Importantly, when co-activated, the index and middle finger RFs not only shrank during physical touch perception, but also during touch observation. Our data, therefore, indicate a similarity between the functional architecture of S1 during touch observation and physical touch perception with respect to single-digit topography and RF shrinkage. These results may allow the tentative conclusion that even primary somatosensory experiences, such as physical touch perception, can be shared amongst individuals.  相似文献   
57.
乙型肝炎病毒基因的整合机制及对宿主的影响   总被引:1,自引:0,他引:1  
乙型肝炎病毒是导致慢性肝炎、肝纤维化、肝细胞癌的主要病因,目前认为乙型肝炎病毒基因整合在其致病机制中具有重要作用,本文试就该领域内目前研究成果做一综述.  相似文献   
58.
59.
保证输血时血清学方面的安全,首要的是对受血者与献血者ABO血型定型,血清学检查通常分两个步骤.正定型通常使用鼠源单克隆抗体检测红细胞表面是否存在A或B抗原.互补的实验即反定型,利用当红细胞上缺乏A或B抗原时,人群可天然产生相对应的抗体的原理,检测血清中是否存在抗-A或者抗-B抗体.确定了受血者红细胞表面的ABO抗原以及血浆中的抗体,便能确定血型,为其提供相合的血液.  相似文献   
60.
保证输血时血清学方面的安全,首要的是对受血者与献血者ABO血型定型,血清学检查通常分两个步骤.正定型通常使用鼠源单克隆抗体检测红细胞表面是否存在A或B抗原.互补的实验即反定型,利用当红细胞上缺乏A或B抗原时,人群可天然产生相对应的抗体的原理,检测血清中是否存在抗-A或者抗-B抗体.确定了受血者红细胞表面的ABO抗原以及血浆中的抗体,便能确定血型,为其提供相合的血液.  相似文献   
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