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排序方式: 共有856条查询结果,搜索用时 11 毫秒
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Gisela Soledad Gualdoni Martín Ricardo Ventureira Tamara Anahí Coll Wilder Alberto Palomino Claudio Gustavo Barbeito Elisa Cebral 《Reproductive biomedicine online》2021,42(3):481-504
Research questionMaternal alcohol consumption produces fetal retardation and malformations, probably associated with placental defects. Does perigestational alcohol consumption up to organogenesis lead to abnormal placentation and embryo growth restriction by disrupting the vascular endothelial growth factor (VEGF) system in embryo–placental development?DesignFemale mice were treated with 10% ethanol in drinking water before and up to day 10 of gestation. Control mice received ethanol-free water. After treatment, the trophoblastic tissue, embryo growth and the angiogenic VEGF pathway were analysed.ResultsFemale mice who had received treatment had resorbed and delayed implantation sites with poor ectoplacental cone development. Reduced trophoblastic area tissue from female mice who had received treatment had abnormal junctional zone and diminished labyrinthine vascularization. After treatment, the labyrinth had increased chorionic trophoblast proliferation, hypoxia inducible factor-1α immunoexpression but reduced apoptosis. The embryo growth was reduced concomitantly with low VEGF immunostaining but high endothelial nitric oxide synthase (eNOS) expression. In junctional and labyrinth of treated female mice, gene and protein immunoexpression of VEGF was reduced and the protein expression of FLT-1 increased compared with controls. Increased activation of kinase insert domain receptor receptor (phosphorylated KDR) and expression of eNOS were observed in placenta of treated female mice. Immunoexpression of metalloproteinase-9, however, was reduced in junctional zone but increased in labyrinth, compared with controls.ConclusionsThese data reveal inadequate expression of VEGF/receptors and angiogenic eNOS and metalloproteinase factors related to abnormal early placentation after perigestational alcohol ingestion, providing insight into aetiological factors underlying early placentopathy associated with intrauterine growth restriction caused by maternal alcohol consumption. 相似文献
95.
目的探讨脑利钠肽(brain natriuretic peptide,BNP)与超声心动图在川崎病急性期及恢复期诊断中的临床意义。方法选取川崎病患儿35例为病例组,以发热、皮疹为主诉的肺炎支原体或病毒感染的48例患儿为对照组,测其急性期与恢复期脑利钠肽及左、右冠状动脉内径值,并做相关分析。结果川崎病患儿急性期脑利钠肽值明显高于恢复期,且差异有统计学意义;川崎病患儿恢复期冠状动脉内径值明显高于急性期,且差异有统计学意义。结论应用超声心动图检测冠状动脉扩张是在恢复期诊断川崎病的重要手段,而脑利钠肽可作为急性期诊断川崎病的生化指标之一。 相似文献
96.
Adhesion of sickle neutrophils and erythrocytes to fibronectin 总被引:2,自引:0,他引:2
The pathophysiology of vaso-occlusive crisis in sickle cell disease involves interactions among blood cells, plasma proteins, and vessel wall components. The initial goal of this work was to quantify the adhesion of sickle red blood cells (RBCs) to fibronectin immobilized on glass under both static and dynamic shear stress conditions. High-power microscopic inspection of static assay plates showed striking numbers of adherent neutrophils as well as RBCs. Sickle neutrophils and RBCs were significantly more adherent to fibronectin than the corresponding normal cells in static adhesion assays. Adhesion of both sickle neutrophils and sickle RBCs in dynamic adhesion assays was promoted by a period of static incubation preceding initiation of shear stress conditions. Adherent neutrophils remained attached at shear stresses up to 51 dyne/cm2; most adherent RBCs were attached at shear stresses up to 13 dyne/cm2, but detached at a shear stress of 20 dyne/cm2. Sickle neutrophil adhesion was enhanced significantly by autologous plasma. Elevated levels of plasma interleukin-6 (IL-6; but not IL-1 or IL-8) were found in 6 of 9 sickle cell disease samples examined, and elevated levels of tumor necrosis factor were found in 2 of 9 samples. Plasma IL- 6 levels correlated positively with both the number of sickle neutrophils adherent to fibronectin and the ability of sickle plasma to enhance adhesion of normal neutrophils to fibronectin. These data suggest possible roles for neutrophil activation and for fibronectin in mediating sickle neutrophil and RBC adhesion. 相似文献
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Inhibition of thromboxane formation in vivo and ex vivo: implications for therapy with platelet inhibitory drugs 总被引:7,自引:1,他引:7
The capacity of platelets to generate thromboxane A2, reflected by measurement of serum thromboxane B2 (TxB2), greatly exceeds the systemic production of thromboxane in vivo. Thus, it is possible that substantial but incomplete inhibition of thromboxane formation ex vivo would still allow marked augmentation of thromboxane production in vivo. To address this hypothesis, we administered aspirin 120 mg, a selective inhibitor of thromboxane synthase (TxSl), 3-(1H-imidazol-1-yl- methyl)-2-methyl-1H-indole-1-propanoic acid (UK-38, 485) 200 mg, and a combination of both drugs to 12 healthy volunteers and measured the effects on serum TxB2 and urinary 2,3-dinor-thromboxane B2 (Tx-M), an index of endogenous thromboxane biosynthesis. Although serum TxB2 was maximally inhibited by 94 +/- 1% after aspirin and 96 +/- 2% after the TxSl, maximal depression of Tx-M was only 28 +/- 8% and 37 +/- 9%, respectively. Combination of aspirin with the TxSl resulted in a small but significant increase in inhibition of thromboxane generation ex vivo (98 +/- 1% v 94 +/- 1%; P less than 0.05), but a disproportionately greater fall in thromboxane synthesis in vivo (58 +/- 7%; P less than 0.01). Consistent with further inhibition of platelet thromboxane synthesis, addition of the TxSl abolished the transient decline in prostacyclin formation after aspirin alone. Administration of a lower dose of aspirin (20 mg) to 6 healthy subjects caused a small reduction in Tx-M (12 +/- 4%; P less than 0.05) and inhibited serum TxB2 by 48 +/- 2%. The relationship between inhibition of platelet capacity to form thromboxane ex vivo (serum TxB2) and synthesis in vivo (Tx-M) departed markedly from the line of identity. When total blockade of the capacity of platelets to generate thromboxane is approached, minor decrements in capacity result in a disproportionate depression of actual thromboxane biosynthesis. These results imply that pharmacologic inhibition of serum TxB2 must be virtually complete before thromboxane- dependent platelet activation is influenced in vivo. 相似文献
99.
Hamilton JA; Whitty GA; Stanton H; Wojta J; Gallichio M; McGrath K; Ianches G 《Blood》1993,82(12):3616-3621
Macrophage colony-stimulating factor (M-CSF or CSF-1) and granulocyte- macrophage CSF (GM-CSF) have been shown to increase human monocyte urokinase-type plasminogen-activator (u-PA) activity with possible consequences for cell migration and tissue remodeling; because monocyte u-PA activity is likely to be controlled in part also by the PA inhibitors (PAIs) made by the cell, the effect of M-CSF and GM-CSF on human monocyte PAI-2 and PAI-1 synthesis was investigated. To this end, elutriation-purified human monocytes were treated in vitro with purified recombinant human M-CSF and GM-CSF, and PAI-2 and PAI-1 antigen and mRNA levels measured by specific enzyme-linked immunosorbent assays and Northern blot, respectively. Each CSF could enhance the protein and mRNA levels of PAI-2 and PAI-1 at similar concentrations for each product. This similar regulation of monocyte PAI expression in response to the CSFs contrasted with that found for the effects of lipopolysaccharide, transforming growth factor-beta and a glucocorticoid. Therefore, PAIs may be modulating the effects of the CSFs on monocyte u-PA activity at sites of inflammation and tissue remodeling. 相似文献
100.
BACKGROUND & AIMS: Microvascular endothelial cells mediate leukocyte homing, angiogenesis, and inflammation and healing and show tissue- specific adhesion molecules and functions. The activation of human intestinal mucosal microvascular endothelial cells (HIMECs) was studied in vitro to uncover possible abnormalities associated with inflammatory bowel disease. METHODS: HIMECs were isolated from normal and inflammatory bowel disease mucosa and assessed for phenotypic and morphological features, proliferative response, leukocyte binding capacity, and adhesion molecule expression. RESULTS: Basal proliferation by HIMECs was less than that of human umbilical vein endothelial cells (HUVECs) but increased proportionally more in response to vascular endothelial growth factor. Proinflammatory stimuli induced an activated, spindle-shaped morphology in HIMEC monolayers. Compared with HUVECs, unstimulated HIMECs showed less adhesiveness for U937 and MOLT4 cells and neutrophils, but cytokines and lipopolysaccharide substantially increased the binding capacity of HIMECs. HIMECs derived from inflammatory bowel disease mucosa showed a markedly greater leukocyte-binding capacity than normal mucosal HIMECs. Patterns of intercellular adhesion molecule 1, vascular cell adhesion molecule 1 and E-selectin messenger RNA expression were distinct in HIMECs, HUVECs, and mucosal mesenchymal cells. CONCLUSIONS: HIMECs represent differentiated endothelial cells with unique functional properties. Their dramatically enhanced capacity to bind leukocytes in inflammatory bowel disease suggests that HIMECs play an important role in initiating or maintaining inflammation. (Gastroenterology 1997 Jun;112(6):1895-907) 相似文献