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Grazyna B Sadowska Xiaodi Chen Jiyong Zhang Yow-Pin Lim Erin E Cummings Oleksandr Makeyev Walter G Besio John Gaitanis James F Padbury William A Banks Barbara S Stonestreet 《Journal of cerebral blood flow and metabolism》2015,35(9):1388-1395
Pro-inflammatory cytokines contribute to hypoxic–ischemic brain injury. Blood–brain barrier (BBB) dysfunction represents an important component of hypoxic–ischemic brain injury in the fetus. Hypoxic–ischemic injury could accentuate systemic cytokine transfer across the fetal BBB. There has been considerable conjecture suggesting that systemic cytokines could cross the BBB during the perinatal period. Nonetheless, evidence to support this contention is sparse. We hypothesized that ischemia–reperfusion increases the transfer of systemic interleukin-1β (IL-1β) across the BBB in the fetus. Ovine fetuses at 127 days of gestation were studied 4 hours after 30 minutes of bilateral carotid artery occlusion and compared with a nonischemic group. Recombinant ovine IL-1β protein was expressed from an IL-1β pGEX-2 T vector in E. coli BL-21 cells and purified. The BBB function was quantified in 12 brain regions using a blood-to-brain transfer constant with intravenous 125I-radiolabeled IL-1β (125I-IL-1β). Interleukin-1β crossed the intact BBB in nonischemic fetuses. Blood-to-brain transport of 125I-IL-1β was higher (P<0.05) across brain regions in fetuses exposed to ischemia–reperfusion than nonischemic fetuses. We conclude that systemic IL-1β crosses the intact fetal BBB, and that ischemia–reperfusion increases transfer of this cytokine across the fetal BBB. Therefore, altered BBB function after hypoxia–ischemia facilitates entry of systemic cytokines into the brain of the fetus. 相似文献
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An Immunohistochemical Study of Matrix Components in Early‐Stage Vascular Canals Within Mandibular Condylar Cartilage in Midterm Human Fetuses 下载免费PDF全文
Shunichi Shibata Tsuyoshi Morita Tamaki Yokohama‐Tamaki Gen Murakami Baik Hwan Cho 《Anatomical record (Hoboken, N.J. : 2007)》2015,298(9):1560-1571
Matrix components of vascular canals (VCs) in human fetal mandibular condylar cartilage (15–16 weeks of gestation) were analyzed by immunohistochemistry. Prevascular canals (PVCs), consisting of spindle‐shaped cells without capillary invasion, were observed within the cartilage. Intense immunoreactivity for collagen type I, weak immunoreactivity for aggrecan and tenascin‐C, weak hyaluronan (HA) staining, and abundant argyrophilic fibers in PVCs indicated that they contain noncartilaginous fibrous connective tissues that was different from those in the perichondrium/periosteum. These structural and immunohistochemical features of PVCs are different from those of previously reported cartilage canals of the long bone. Capillaries entered the VCs from the periosteum and ascended through VCs. Following capillary invasion, loose connective tissue had formed in the lower part of VCs, and immunoreactivity for collagen types I and III, tenascin‐C, and HA staining was evident in the matrix of loose connective tissue. No chondroclasts or osteogenic cells were seen at the front of capillary invasion, although small, mononuclear tartrate‐resistant acid phosphatase (TRAP)‐positive cells were present. Meanwhile, TRAP‐positive, multinucleated chondroclasts and flattened, osteoblast‐like cells were observed in the loose connective tissue at the lower part of VCs. These results may indicate slow progress of endochondral ossification in human fetal mandibular condyle. Further, unique matrix components in PVCs/VCs, which were different from those in cartilage canals in long bone, may reflect the difference of speed of endochondral ossification in cartilage canals and human fetal mandibular condyles. Anat Rec, 298:1560–1571, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
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人胎肝干细胞体外分离、培养及鉴定 总被引:2,自引:0,他引:2
研究人胎肝干细胞体外分离纯化方法,并对其进行初步鉴定及生物学特性分析。采用胶原酶消化、重力沉降及密度梯度离心方法分离人胎肝干细胞,通过免疫细胞化学方法对其进行初步鉴定,以及应用流式细胞仪等对其生长状况进行评估。所获得的原代细胞共传8代,细胞呈小梭形或三角形,体积较小,胞核较大,而胞浆较少;第4代细胞中进入生长期的细胞约占88.2%;免疫细胞化学染色显示细胞胞质中ALB、CK19染色阳性。人胎肝中存在具有肝干细胞特征的细胞,它们可能会成为细胞移植及肝移植良好的细胞资源。 相似文献
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目的:分析晚孕期脐动脉舒张期血流信号消失时胎儿生长发育和出生时情况。方法采用彩色超声诊断仪检测脐动脉血流信号,对比分析脐动脉血流正常与脐动脉舒张期血流消失时胎儿的生长发育指标和出生时Apgar评分。结果脐动脉舒张期血流消失的胎儿生长发育小于孕龄的发生率明显高于正常组,出生时宫内窘迫的发生率也明显高于正常组。结论晚孕期脐动脉舒张期血流消失提示胎儿宫内缺氧,胎儿生长发育相对缓慢。 相似文献
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〖H观察当归补血汤主要吸收成分对2型糖尿病模型GK大鼠肾保护作用及可能机制。方法 UPLCMS/MS定性定量吸收入血活性成分(ABCs),确定ABCs组成,定量1g母方中ABCs浓度。GK大鼠按血糖随机分为模型组、当归补血汤组及吸收成分(ABCs)组,每组10只,给药组分别灌胃当归补血汤(4g/kg)、吸收入血的生物活性成分(剂量相当于母方含量,即咖啡酸5.36mg/kg,芒柄花素2.68mg/kg,毛蕊异黄酮2.56mg/kg,阿魏酸1.36mg/kg,黄芪甲苷0.45mg/kg,丁苯酞0.16mg/kg,蒿本内酯0.16mg/kg),10只普通Wistar大鼠作为空白对照,给予等量生理盐水,每日1次,连续给药28d。观察指标:①肾脏系数、尿总蛋白和尿白蛋白;②肾组织氧化应激;③病理切片观察肾脏组织形态。结果 当归补血汤及ABCs均能够改善糖尿病大鼠的肾脏肥大,显著降低糖尿病模型大鼠尿总蛋白、尿白蛋白和肾脏MDA水平(P<0.05),显著升高肾脏总SOD活力(P<0.05),且对肾脏组织病理形态学有保护作用;与当归补血汤组比较,ABCs作用不如汤剂显著。结论 ABCs能够代表母方当归补血汤发挥对GK大鼠的肾保护作用,机制涉及氧化应激。母方中除ABCs外,其微量元素、氨基酸、多糖等其他成分也同时发挥着药效作用。 相似文献
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