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Endothelial modulation of vasoconstrictor responses to endothelin-1 in human placental stem villi small arteries.
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S. Sabry F. Mondon M. Levy F. Ferr A. T. Dinh-Xuan 《British journal of pharmacology》1995,115(6):1038-1042
1. The aim of this study was to assess the role of endothelial cells in the modulation of vasocontractile responses to endothelin-1 (ET-1) of human placental vasculature. 2. Isolated stem villi small arteries (diameter = 170-250 microns) were obtained from healthy parturients who underwent caesarean surgery during the 39th week of pregnancy for cephalo-pelvic disproportion. Isometric tension was measured in vascular rings mounted in a myograph system and challenged with ET-1 (10(-12) to 10(-6) M). 3. The vasocontractile response to ET-1 was significantly (P < 0.001) increased in endothelial-denuded (active tension = 1156 +/- 214 mN mm-1) as compared with endothelial-preserved vascular rings (active tension = 458 +/- 48 mN mm-1). This difference was significantly (P < 0.05) but only partly abolished by the NO synthase inhibitor N omega-nitro-L-arginine (L-NOARG, 10(-4) M). 4. In endothelial-preserved rings submaximally precontracted with 5-hydroxytryptamine (10(-6) M), ET-1 (10(-12) to 10(-9) M) induced dose-dependent relaxation (maximum relaxation = 70 +/- 7%) at 10(-9) M, which was followed, at higher doses (10(-8) to 10(-6) M), by a contraction. In contrast, no relaxation was seen in endothelial-denuded rings. The relaxation in rings with endothelium was significantly (P < 0.001) reduced by L-NOARG (10(-4) M. Moreover, it was totally abolished by combined pretreatment with L-NOARG (10(-4) M) and the sulphonylurea glibenclamide (10(-5) M).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
3.
BACKGROUND: Fatty acid oxidation disorders may cause sudden and unexpected infant death and are associated with the histological hallmark of hepatic steatosis. The goal of the present study was to assess the value of post-mortem molecular analysis for medium-chain acyl-coenzyme A dehydrogenase (MCAD) and mitochondrial trifunctional protein (MTP) defects in unexplained sudden infant death (SID) associated with fatty infiltration of the liver. MCAD catalyzes the first step of medium-chain fatty acid oxidation while MTP catalyzes the last three steps of long-chain fatty acid oxidation. METHODS: In a retrospective study, 220 consecutive cases of sudden and unexplained infant death certified by medical examiners at Wake Forest University Medical Center were assessed for hepatic steatosis. Subjects with evidence of hepatic steatosis were screened for mutations in MCAD and MTPalpha-subunit using DNA isolated from paraffin-embedded liver tissue, single-strand conformation variance, and nucleotide sequence analyses. RESULTS: Sixteen cases (7.3%) were associated with diffuse micro-vesicular or mixed micro- and macro-vesicular hepatic steatosis. Two of these 16 cases (12.5%) had disease-causing mutations. One was homozygous for the prevalent MCAD A985G mutation. The second was a compound heterozygous for the prevalent MTP G1528C mutation and a novel 1 bp deletion in exon 18 of the MTPalpha-subunit gene. CONCLUSIONS: A significant proportion (7.3%) of SID is associated with hepatic steatosis. The present data support post-mortem molecular analysis for the MCAD A985G and MTP G1528C prevalent mutations in cases of sudden and unexplained infant death associated with hepatic steatosis. 相似文献
4.
目的:探讨IL-6对人精子顶体反应(AR)的影响机制。方法:采用BAEE/ADH法测定精子顶体酶的活性,以及通过FITC-PSA法检测精子顶体反应。结果:IL-6可诱导精子顶体酶及超氧化物歧化酶(SOD)的活性,促进精子顶体反应;胞外Ca2+单独不能诱导精子顶体反应,且没有胞外Ca2+的参与,IL-6也不能诱导精子顶体反应;蛋白激酶C(PKC)抑制剂calphC能逆转IL-6诱导的精子顶体反应。结论:IL-6对精子顶体反应有一定的促进作用,可能通过诱导精子的顶体酶和SOD活性等途径来实现,在此作用中,也涉及了PKC的激活,且还需要外源性Ca2+的参与。 相似文献
5.
Sabry MA Farag TI Shaltout AA Zaki M Al-Mazidi Z Abulhassan SJ Al-Torki N Quishawi A Al Awadi SA 《Clinical genetics》1999,55(1):44-49
We describe 2 unrelated Bedouin girls who met the criteria for the diagnosis of Kenny-Caffey syndrome. The girls had some unusual features--microcephaly and psychomotor retardation--that distinguish the Kenny-Caffey syndrome profile in Arab children from the classical Kenny-Caffey syndrome phenotype characterized by macrocephaly and normal intelligence. The 2 girls did not harbor the 22q11 microdeletion (the hallmark of the DiGeorge cluster of diseases) that we previously reported in another Bedouin family with the Kenny-Caffey syndrome (Sabry et al. J Med Genet 1998: 35(1): 31-36). This indicates considerable genetic heterogeneity for this syndrome. We also review previously reported 44 Arab/Bedouin patients with the same profile of hypoparathyroidism, short stature, seizures, mental retardation and microcephaly. Our results suggest that these patients represent an Arab variant of Kenny-Caffey syndrome with characteristic microcephaly and psychomotor retardation. We suggest that all patients with Kenny-Caffey syndrome should be investigated for the 22q11 microdeletion. Other possible genetic causes for the Kenny-Caffey syndrome or its Arab variant include chromosome 10p abnormalities. 相似文献
6.
5992例孕产妇梅毒筛查与分析 总被引:1,自引:0,他引:1
目的 了解妊娠期梅毒的流行情况及对围产结局的影响。方法 对5992例孕产妇进行甲苯胺红不加热血清试验(TRUST)筛查,对TRUST阳性病例再进行梅毒螺旋体血清颗粒凝集试验(TPPA)确诊。并对围产结局进行观察分析。结果 5992例孕产妇,检出梅毒患者43例(0.72%),其中30例经青霉素治疗的患者其新产儿经半年以上随访无1例感染梅毒,在未治疗的13例患者中有10例分娩的新生儿TPPA滴度均≥1:40,其中2例为先天性梅毒。1例为死亡梅毒婴儿。结论 开展妊娠期梅毒血清学的产前筛查,加强对妊娠期梅毒的治疗,对减少先天性梅毒的发生尤为重要。 相似文献
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中文Frost多维度完美主义问卷的信效度检验 总被引:24,自引:1,他引:24
目的:检验中文Frost多维度完美主义问卷(FMPS)信效度。方法:共有1280名大学本科生作为被试填写了FMPS问卷,其1000名被试的数据用于探索性因素分析,另外280名被试的数据用于验证性因素分析。部分被试被要求填写测量焦虑、抑郁、强迫等心理困扰的问卷,作为效标效度检验。结果:中文版Frost多维度完美主义问卷由五个维度组成。各维度的项目载荷在0.45—0.78之间。五个因素(担心错误、条理性、父母期望、个人标准和行动的疑虑)可以解释总方差的53.7%。各维度的内部一致性系数为0.64-0.81。重测信度为0.63-0.82。中文FMPS与焦虑、抑郁、强迫等心理困扰也有屉著的相关,其中“担心错误”和“行动的疑虑”与各种心理困扰的相关系数在0.30—0.70之间。结论:中文FMPS的维度结构与其英文原问卷相似,且具有令人满意的信效度。适合在中国文化环境下使用。 相似文献
9.
目的观察正常孕妇妊娠晚期和妊高征患者血小板参数的变化及临床意义。方法采用日本Sysmex KX-21型血液细胞分析仪分别对正常孕妇(118例)、妊高征患者(59例)及对照组(正常婚检妇女59例)的血液标本进行血小板(PLT)计数、平均血小板体积(MPV)、血小板分布宽度(PDW)的测定。结果妊高征组和正常孕妇组的MPV、PDW显著高于对照组(P〈0.01);妊高征组MPV、PDW明显高于正常孕妇组(P〈0.05);妊高征组的PLT显著低于对照组(P〈0.01)。结论妊高征患者由于血小板消耗和破坏增加,导致血小板减少,MPV、PDW明显增高,因此,检测血小板参数对预测妊高征的发生有一定的参考意义。 相似文献
10.
Ebraheim NA Sabry FF Nadim Y 《Foot & ankle international / American Orthopaedic Foot and Ankle Society [and] Swiss Foot and Ankle Society》1999,20(12):794-796
The internal architecture of the talus has not previously been well described even though the morphological anatomy and the blood supply have been studied extensively. This study describes the internal architecture of the talus regarding its trabecular orientation, using high-resolution x-ray images of 13 dry tali and thick sections in the coronal, sagittal, and axial planes. The trabecular arrays and their relationship to talar fractures are described. The trabecular content of the neck of the talus is less than that of the head or the body. The direction of the trabecula in the neck is different from the orientation of the talar body trabeculae. 相似文献