Nucleus locus coeruleus: Evidence for α1-adrenoceptor mediated hypotension in the cat

Summary The Bezold-Jarisch reflex characterized by hypotension and bradycardia was elicited in anaesthetized artificially respired dogs (pretreated with a beta-adrenoceptor antagonist) using capsaicin 10 g/kg (i.v.). Intracisternal administration of the highly selective clonidine-like alpha₂ adrenoceptor agonists B-HT 920 (10 g/kg) or B-HT 933 (30 g/kg) significantly facilitated this reflex bradycardia. The involvement of central alpha₂-adrenoceptors is suggested as intracisternal administration of the alpha₂ adrenoceptor blocking drugs yohimbine (50 g/kg) and piperoxan (50 g/kg) antagonized this facilitation. B-HT 920 also facilitated the vagally mediated baroreceptor reflex to the hypertensive effect of intravenous noradrenaline (3 g/kg). Although the Bezold-Jarisch reflex and the baroreceptor reflex have different afferent pathways, both reflexes may either converge into a common pathway or have separate neuronal chains within the medulla; however, this study indicates that both have a similar central modulatory system stimulated by alpha₂ adrenoceptors.     

新型冠状病毒Alpha变异株实验室检测研究

目的 对一例新冠肺炎境外输入病例进行实验室检测,并对新型冠状病毒（severe acute respiratory syndrome coronavirus 2,SARS - CoV - 2）变异株进行鉴定,了解不同样本类型中新冠病毒的检出情况。方法 采集咽拭子、痰液、粪便、尿液和血液多种类型样本共13份,分别提取核酸,用荧光RT - PCR法检测SARS - CoV - 2。使用纳米孔MinION Mk1C测序仪,对阳性咽拭子样本进行实时SARS - CoV - 2靶向扩增全基因组测序,运用artic - ncov2019、DNAstar和Mega等软件对测定序列进行处理和分析。结果 咽拭子、痰液、粪便、血浆和尿沉渣样本中均检出SARS - CoV - 2核酸,咽拭子和血浆样本在发病的前四天均能检出,尿沉渣样本在发病当天能检出。基于纳米孔测序技术,7 h即获得SARS - CoV - 2全基因组数据,经分析显示为新冠病毒Alpha变异株。结论 本例境外输入新冠肺炎确诊病例的病原为SARS - CoV - 2 Alpha变异株,咽拭子、血浆样本和尿沉渣样本在发病早期均能检出SARS - CoV - 2核酸。     

血清壳多糖酶3样蛋白1、肝纤维化4项及AFP的检测在不同肝脏疾病中的应用价值探讨

目的探讨血清壳多糖酶3样蛋白1(CHI3L1)、肝纤维化4项及甲胎蛋白(AFP)在不同肝脏疾病中的应用价值。方法选取172例符合条件的慢性乙型肝炎病毒感染者,分为慢性乙型肝炎组、肝硬化组和肝癌组。收集同期健康体检者30例作为正常对照组。比较各组间指标的差异,采用受试者工作特征(ROC)曲线分析各指标鉴别诊断效能。采用Spearman秩相关分析各指标与疾病严重程度的相关性。结果血清CHI3L1及肝纤维化4项在肝硬化组和肝癌组明显高于慢性乙型肝炎组和正常对照组(P <0.05)。血清AFP浓度在肝癌组明显高于其他各组,上述差异均有统计学意义(P <0.01),其诊断肝癌的AUC为0.912。ROC曲线分析显示CHI3L1在肝硬化组和慢性乙型肝炎组,慢性乙型肝炎组和正常对照组之间的鉴别诊断效能较好,AUC分别为0.853和0.845。Spearman相关性分析显示肝脏疾病的严重程度与各血清学指标均呈正相关(P <0.05)。结论 CHI3L1、肝纤维化4项及AFP的检测可以辅助诊断慢性肝炎及其肝纤维化导致的肝硬化等不同肝脏疾病,值得在临床推广和进一步的研究。     

大脑功能及α波优势频分析在厌学青少年的应用

目的探讨厌学青少年大脑功能状态和α波优势频特点及对心理咨询的指导价值。方法以厌学进行心理咨询的青少年为研究组，以发展咨询的青少年为对照组。统一使用ML-2001脑功能状态检查仪对其脑功能状态和α波优势竞争频率及熵值进行测量，并对测量结果进行分析。结果两组的α波竞争优势主频分布于各频之间无显著性差异，但主频与次频之差均值和熵值差异显著（P〈0.01）；各脑区同时段主频不统一和多频互扰现象和大脑少氧、疲劳、左右对称性、前后功率逆转情况差异显著（P〈0.01）。结论厌学青少年大脑工作状态和脑电活动的有序性和统一性较差，影响厌学青少年的认知和行为。     

孕妇血清标记物在中孕筛查中的应用

目的 :通过对孕妇血清标记物甲胎蛋白 (AFP)和人绒毛膜促性腺激素 ( β -HCG )测定来筛选缺陷儿。 方法 :用放射免疫法对 6 2例孕 14～ 2 3周妊娠妇女上述标记物连测 3次 ,每次隔 12～ 14d ,以两次异常为高危个体。每例筛查者跟踪至胎儿出生后。结果 :在筛查中发现了 1例先天愚型和 1例无脑儿。结论 :上述两种血清标记物可以作为神经管缺陷和先天愚型筛查的一项常规方法     

甲胎蛋白启动子调控表达p53基因的肝癌细胞靶向性基因治疗？…

目的 利用含有人甲胎蛋白启动子的腺相关病毒载体,构建能在人肝癌细胞株中特异表达目的的基因的质粒。方法 通过设计含有特定酶切点位点的引物,选择性地从人基因组中扩增出人甲胎蛋启动子（ＡＦＰ ｐｒｏｍｏｔｅｒ）主列并克琶含有绿色荧光蛋白（ＧＦＰ报基因的质粒,ｐＲＴ－ＵＦ５上,构建成含报告基因的重组腺相关病毒质粒ｒＡＡＶ－ＡＦＰ－ＧＦＰ转染表达ＡＦＰ的Ｈｅｐ Ｇ２细胞株和不表达ＡＦＰ的２９３因的质粒ｒＡＡ     

冠脉循环中血小板活化状态对冠心病致病作用的研究

目的：探讨冠脉循环中血小板活化状态在冠心病（ＣＨＤ）发病学中的意义。方法：用放免等方法对受试冠状静脉窦（ＣＳ）及升主动脉（ＡＯ）血行血小板膜表面α－颗粒膜蛋白（α－ＧＭＰ－１４０）和循环内皮细胞（ＣＥＣ）等测定。结果：ＣＨＤ患冠脉循环中α－ＧＭＰ－１４０含量和ＣＥＣ浓度均明显升高（Ｐ〈０．０１）,以急心肌梗塞（ＡＭＩ）组为明显,冠脉狭窄愈严重,二升高愈明显,病灶多发比单发升高明显。结论：ＣＨＤ患冠脉循环中血小板高度激活,在ＣＨＤ的发生发展中有一定的意义。     

An examination of factors influencing adrenergic transmission in the pithed rat,with special reference to noradrenaline uptake mechanisms and post-junctional α-adrenoceptors

Summary Adrenergic mechanisms were analysed in the pithed rat to determine to what extent the actions of drugs observed in vitro are relevant in situ.The drugs examined were those which are known to block the neuronal or extraneuronal uptake of noradrenaline (cocaine, desipramine and corticosterone) or to be antagonists at post and/or pre-junctional -adrenoceptors (prazosin and yohimbine) together with the antidepressant, mianserin, which has been implicated in several of these actions. These drugs were tested against the arterial diastolic pressor, cardiac chronotropic and vas deferens responses to sympathetic nerve stimulation, to indirect sympathomimetics or to direct sympathomimetics, which were chosen according to whether they were substrates for noradrenaline uptake processes or selective between adrenoceptors.Pressor and cardiac responses to sympathetic nerve stimulation or to intravenous noradrenaline were potentiated by blockade of neuronal uptake but only the pressor effect of noradrenaline was potentiated by blockade of extraneuronal uptake. The effects of the antagonists suggested that the pressor effects of noradrenaline and of sympathetic nerve stimulation result from a combination of activation of ₁- and ₂-adrenoceptors, but that the effect of noradrenaline had a relatively greater contribution from the ₂-adrenoceptors. Mianserin was found to potentiate adrenergic responses at low doses, to produce limited antagonism at post-junctional ₁-adrenoceptors in high doses but to have no detectable effect at postjunctional ₂-adrenoceptors.     

Adrenergic influences on the control of blood-brain barrier permeabilit

Summary The central adrenergic innervation of the cerebral microvessels may play a role in the control of blood-brain barrier permeability. To pursue the study of this hypothesis we investigated the effect of noradrenaline on both the permeability of the blood-brain barrier to sodium fluorescein and on the pinocytotic activity of cerebral endothelial cells in the rat. Noradrenaline, stereotactically injected in the right lateral cerebral ventricle, significantly increased the cerebral extraction ratio of sodium fluorescein in a dose-dependent way. The same effect was induced by phenylephrine. Prostaglandin F₂ had no significant effect on the passage of sodium fluorescein through the blood-brain barrier.The effect of noradrenaline (150 µg) on the cerebral extraction ratio of sodium fluorescein was totally blocked by phenoxybenzamine (25 mg/kg i.p., 24 h before noradrenaline). Noradrenaline (150 µg) significantly increased the pinocytotic activity of cerebral endothelial cells. Phenoxybenzamine (as above) reduced the effect of noradrenaline on pinocytosis.It is concluded that noradrenaline increases the blood-brain barrier's permeability to sodium fluorescein, most probably through an effect on alpha adrenoceptors. The increase induced in the blood-brain barrier's permeability by noradrenaline seems to be due, at least in part, to an increase in the pinocytotic activity of endothelial cells. Send offprint requests to A. Sarmento at the above address     

Detection of α S1-casein in vomit from bottle-fed babies by enzyme-linked immunosorbent assay

Summary This study describes a sensitive enzyme-linked immunosorbent assay (ELISA) using rabbit anti-bovine S1-casein antibody for the detection of commercial milk and milk-containing vomit. The antibody does not react with other human body fluids such as breast milk. The stability of S1-casein antigenic activity was examined after storage at different temperatures and enzyme digestion. There was no decrease after storage for one year at room temperature but 40% of the activity was lost after 6 months at 37°C. Enzyme digestion (6 hours, 37°C) resulted in 65 70% loss of activity but the antibody reacted with the peptide fragments of S1-casein. Vomit samples from 3 normal infants were tested by ELISA, and a S 1-casein could be detected in 1 cm² stain.