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Thomas Krebs Michael Boettcher Hansjörg Schäfer Georg Eschenburg Katharina Wenke Birgit Appl Beate Roth Thomas Andreas Carla Schmitz Rebecca Fahje Birthe Jacobsen Bastian Tiemann Konrad Reinshagen Kurt Hecher Robert Bergholz 《Surgical endoscopy》2014,28(8):2437-2442
Background
The pathogenesis of intestinal dysmotility in gastroschisis is not completely understood. Peel formation and disorganization of interstitial Cajal cells (ICC) have been proposed in humans. The aim of this study was to evaluate the impact of prenatal coverage of gastroschisis on gut inflammation and expression of ICC in a fetal lamb model.Methods
Twenty-one German blackhead sheep with an abdominal wall defect that was created fetoscopically on day 77 of 145 days gestation were used in this study. Intrauterine surgery with the aim to cover the defect was performed 3 weeks later; two fetuses were covered completely, 5 partially and 11 remained uncovered. Three fetuses without gastroschisis were used as controls. All fetuses were retrieved by cesarean section at day 135. Samples of the small intestine were stained with hematoxylin and eosin for histologic analysis of peel formation and serosal and muscular thickness. For ICC detection, immunohistochemistry using anti-CD117 (c-Kit) antibody was used.Results
In all samples with exposure to amniotic fluid, peel formation and significantly decreased ICC were found. Complete coverage reduced peel formation and disorganization of ICC compared to uncovered animals almost to the level of controls.Conclusions
Peel formation and ICC derangement were significantly reduced by prenatal coverage of gastroschisis. Moreover, this animal model mimics the histopathological bowel changes as seen in human gastroschisis and may, therefore, be used for further research on the pathophysiology and fetal therapy of this malformation. 相似文献63.
64.
Stoll Svenja Macha Kosmas Marsch Armin Gerner Stefan T. Siedler Gabriela Fröhlich Kilian Volbers Bastian Strasser Erwin F. Schwab Stefan Kallmünzer Bernd 《Journal of neurology》2020,267(7):2007-2012
Journal of Neurology - Oral Factor Xa inhibitors for the prevention of stroke in atrial fibrillation require dose adjustment based on certain clinical criteria, but the off-label use of the reduced... 相似文献
65.
Schönfeld Michael H. Kabiri Reza Kniep Helge C. Meyer Lukas Sedlacik Jan Ernst Marielle Broocks Gabriel Faizy Tobias D. Cheng Bastian Thomalla Götz Fiehler Jens Hanning Uta 《Journal of neurology》2020,267(5):1401-1406
Journal of Neurology - To analyze the incidence of peripheral emboli after successful mechanical thrombectomy (MT) of intracranial large vessel occlusions (LVO). We performed a prospective analysis... 相似文献
66.
67.
Summary: Physical interactions between T cells and antigen-presenting cells (APCs) form the basis of any specific immune response. Upon cognate contacts, a multimolecular assembly of receptors and adhesion molecules on both cells is created, termed the immunological synapse (IS). Very diverse structures of ISs have been described, yet the functional importance for T-cell differentiation is largely unclear. Here we discuss the principal structure and function of ISs. We then focus on two characteristic T-cell–APC pairs, namely T cells contacting dendritic cells (DCs) or naive B cells, for which extremely different patterns of the IS have been observed as well as fundamentally different effects on the function of the activated T cells. We provide a model on how differences in signaling and the involvement of adhesion molecules might lead to diverse interaction kinetics and, eventually, diverse T-cell differentiation. We hypothesize that the preferred activation of the adhesion molecule leukocyte function-associated antigen-1 (LFA-1) and of the negative regulator for T-cell activation, cytotoxic T-lymphocyte antigen-4 (CTLA-4), through contact with naive B cells, lead to prolonged cell–cell contacts and the generation of T cells with regulatory capacity. In contrast, DCs might have evolved mechanisms to avoid LFA-1 overactivation and CTLA-4 triggering, thereby promoting more dynamic contacts that lead to the preferential generation of effector cells. 相似文献
68.
Safety and efficacy of intravenous immunoglobulin prophylaxis in pediatric head trauma patients: A double-blind controlled trial 总被引:6,自引:0,他引:6
Ann M. Gooding John F. Bastian Bradley M. Peterson Nevin W. Wilson 《Journal of critical care》1993,8(4):212-216
Infection is one of the major complications of severe head trauma in children. To assess whether intravenous immunoglobulin (IVIg) decreases the incidence of secondary infection after head injury in children, a randomized, double-blind trial was performed. Thirty-three children (mean age, 6.67 years; mean injury severity score, 32.8; mean Glasgow coma score, 6.1) with severe head injuries were enrolled; 1 child was excluded, 18 received IVIg, and 14 received the placebo preparation. Four hundred milligrams per kilogram of IVIg or albumin placebo was administered within 48 hours of admission. IgG levels were obtained before the infusion and then 1 week later. Patients were monitored for evidence of infection for the next 21 days. There was a 66% increase in mean IgG levels in the treatment group compared with 45% in the control group (P = .057). One death occurred in the IVIg group and two in the placebo group. No significant differences in the incidence of pneumonia, sepsis, presumed sepsis, or any other type of infection was noted. There was no difference in the number of days on mechanical ventilation or in number of hospital days. There were no side effects. It is concluded that prophylactic administration of commercial IVIg at a dose of 400 mg/kg, although safe, had no effect on the incidence of secondary infections in children with severe head injuries. 相似文献
69.
王文志 杨定焯 蒋建军 吴涛 程晓光 周琦 卓铁军 张华俦 项静 王洪复 区品中 刘建立 徐苓 黄公怡 黄琪仁 HS Barden LS Weynan KG Fqukner 孟迅吾 《中国神经再生研究》2008,12(50):9997-10000
背景: 不同地区骨峰值和标准差不同,对骨质疏松诊断率有较大影响。探讨建立一完整数据库为中国人骨质疏松诊断准确性提供依据。
目的:探讨青年人腰椎骨密度和标准差正常参考值影响骨质疏松症检出率的程度。
设计、时间及地点:调查分析,于1997-01/1999-12分别在北京、上海、广州、南京、嘉兴和成都市完成。
对象:采用前瞻性及回顾性方法对全国6个中心骨密度参考数据库中11 418人进行调查统计分析;男3 666人,女7 752人;年龄20岁~90岁;分别来自北京(2 385人)、广州(1 178人)、上海(1 404人)、南京(2 938人)、成都(1 425人)、嘉兴(2 088人),受试者来源于社区调查、健康体检和健康志愿者。
方法:用GE-Lunar公司的DXA仪测量骨密度,调查全国6个中心11 418人L2~L4腰椎后前位和髋部骨密度,建立了骨密度参考数据库。6个中心的仪器内部精度0.3%~0.7%,仪器间的精度1.1%。
主要观察指标:①6个中心不同年龄组腰椎骨密度分布。②青年人群骨密度及其标准差值对骨质疏松症检出率的影响。
结果:中国汉族女性以腰椎进行骨质疏松症诊断的青年人群的骨密度和标准差值,6个中心,最大差值分别为0.098 g/cm2和0.027 g/cm2。用6个中心及总体各自的青年人平均骨密度和标准差值为参考标准,对同一人群计算T-score和获得的骨质疏松症检出率不相同;发现青年人平均骨密度每变化0.01 g/cm2,则骨质疏松症检出率变化1.6%(呈正相关),其标准差值每变化 0.01 g/cm2,则骨质疏松症检出率变化4%(呈负相关)。
结论:青年人平均骨密度和标准差值不同引起骨质疏松症检出率也不相同。为了让不同中心的骨质疏松症检出率有可比性,建议同一个类型的骨密度仪,同一个种族,同一个地区用一个设计较完善大样本的参考数据库,以其青年人正常参考值计算T-score。 相似文献
70.
Objective To investigate the clinical and pathological characteristics of pauci-immune crescent glomerulo~nephritis (PICGN) in Chinese patients. Methods During 13 years (1985-1998), 6400 patients underwent non-transplanting renal biopsy. Twenty-four patients were diagnosed as PICGN. All clinical and laboratory data of these patients were collected from the patients’ records and used for detailed analysis. The diagnosis is based on clinico-pathologic findings. Results Of the 24 patients, 16 were females and 8 were males, with median age of 33 years (ranged 10-76 years). Microscopic polyarteritis (MPA) (33.3%) and systemic vasculitis (8.3%) were the secondary diseases. The incidence of PICGN was 0.38% in renal biopsies and 22.9% in crescentic glomerulonephritis. Clinically, most patients (75.0%) showed rapidly progressive nephritis with enlarged kidneys. At onset, gross hematuria was noted in 58.3% of patients, hypertension in 45.8%, nephrotic syndrome in 41.7%, and oliguria in 25.0%. However, systemic symptoms were rare except for anemia. Pathologically, necrosis of glomerular capillaries (62.5%), infiltration of monocytes and neutrophil cells in glomeruli (66.7%), and vasculitis in the interstitium (53.3%) were observed. In addition, glomerulosclerosis was noted in 45.8%, severe tubular atrophy in 83.3% and interstitial fibrosis in 75.0%. Anti-neutrophil cytoplasmic antibodies (ANCAs) were positive in 52.2%. All patients except two received intensively immunosuppressive therapy. Sixteen patients were available for long-term follow up (median 29.8 months, range 8-92 months). Twelve of them had life-sustaining renal function, four had normal serum creatinine (<124?μmol/L) and only 4 patients were dialysis-dependent. Conclusion PICGN is not rare in China. Early diagnosis and administration of immunosuppressive therapy, particularly in patients with rapidly progressive glomerulonephritis (RPGN), are important for good prognosis. 相似文献