大白鼠下丘脑促肾上腺皮质激素(ACTH)样免疫反应神经元的分布及功能意义

本文应用免疫细胞化学技术观察大白鼠下丘脑促肾上腺皮质激素样神经元胞体,纤维及串珠样膨体的分布。胞体位于弓状核、下丘脑前核的腹侧、视上背侧连合、室周层的腹侧区及乳头体核腹侧。纤维及串珠样膨体广泛地分布于下丘脑,串珠样膨体在室旁核和室周层密集。串珠样膨体贴室管膜分布,伸至室管膜下神经毯,有的穿行室管膜上皮细胞之间并多与室管膜上皮细胞接触或穿过室管膜上皮细胞之间至第三脑室腔。在第三脑室侧壁的室管膜上皮细胞之间偶见促肾上腺皮质激素反应细胞。室旁核区促肾上腺皮质激素免疫反应串珠样膨体可能作用于催产素和后叶加压素神经元,控制催产素和后叶加压素的分泌和释放。室周层的串珠样膨体直接与脑脊液接触可认为是促肾上腺皮质激素神经元释放分泌产物的另一途径。     

不同年龄组儿童甲状腺测量值及其变化的研究

调查了90具童尸用状腺的基本形态,可分四型。其中以甲状腺由两侧叶及峡部组成者为最多,占50.22%。测量了甲状腺各部的长、宽、厚。分年龄组进行了数据的统计学处理,并计算出儿童与成人甲状腺各部相应值的百分比。结果显示:小儿甲状腺侧叶的长度和宽度在幼儿期(1—3岁)就已发育近成人的一半。随着年龄的增长,甲状腺各部的均值逐渐增加。除各部的宽度以及锥体叶的长度外,各相邻两组间同项均数的比较,经双侧T检验发现差异具有高度显著性(P<0.01)。     

西拉普利对低氧大鼠肺动脉和心肌细胞增殖的抑制作用

目的：探索cilazapril 对低氧大鼠肺血管和心肌细胞增殖的抑制机理。 方法： 采用生化、放射免疫、免疫组织化学、细胞凋亡标记和血流动力学技术研究低氧肺血管及心肌细胞增殖和结构重建。 结果： （1）低氧大鼠mPAP显著增高，伴有肺动脉血管管腔狭窄、管壁增厚，心肌肥大，R/L+S增高。（2）B组、C组大鼠肺动脉和右心肌细胞增殖指数（PI）均分别明显高于A组，而C组明显低于B组。ET-1免疫组化染色阳性细胞主要分布在肺动脉血管壁和心肌细胞上，染色程度由强到弱依次为B组>C组>A组。（3）B组大鼠ET-1水平和ACE活性明显高于A组，而C组显著低于B组。（4）直线相关分析显示ET-1、ACE分别与R/(L+S)、mPAP、肺动脉PI、心肌PI呈正相关；多元回归分析显示ET-1和ACE可能是影响PI的主要因素。 结论： 低氧大鼠存在细胞过度增殖状态，继发肺血管、右心结构重建是低氧性肺动脉高压发病机理之一。Cilazapril通过抑制ACE和ET-1的促增殖作用，阻止肺血管及心肌重建，对低氧性肺动脉高压的防治有一定作用。     

Wu T_(11)(CD2)-小鼠抗人绵羊红细胞受体杂交瘤细胞系的建立

本文报道用T细胞系JMN1免疫BALB/c小鼠,然后取免疫脾细胞与小鼠骨髓瘤细胞系X 63Ag8.653融合。用扁桃腺冰冻切片免疫酶染色法,筛选出一株稳定分泌IgG1亚类的抗绵羊红细胞受体(ER)单扰(McAb)的杂交瘤—WuT11。通过E玫瑰花结形成抑制试验,膜抗原抽提物对WuT11的间接免疫荧光阻断试验,对外周血单个核细胞(PBMC)及其E~ 、E~-层细胞,T、B和非T非B细胞系的反应特征以及FACS的反应曲线等,证明WuT11与OKT11和anti-CCT3相类似,竞争抑制试验证明WuT11与anti-CCT3识别同一表位。用WuT11进行亲和层析,提取的相应抗原经SDS-PAGE,测得分子量为50KDa的糖蛋白,证明WuT11属CD_2,为识别人ER的单抗。     

Antibody dynamics to SARS-CoV-2 in asymptomatic COVID-19 infections

Background

The missing asymptomatic COVID-19 infections have been overlooked because of the imperfect sensitivity of the nucleic acid testing (NAT). Globally understanding the humoral immunity in asymptomatic carriers will provide scientific knowledge for developing serological tests, improving early identification, and implementing more rational control strategies against the pandemic.

Measure

Utilizing both NAT and commercial kits for serum IgM and IgG antibodies, we extensively screened 11 766 epidemiologically suspected individuals on enrollment and 63 asymptomatic individuals were detected and recruited. Sixty-three healthy individuals and 51 mild patients without any preexisting conditions were set as controls. Serum IgM and IgG profiles were further probed using a SARS-CoV-2 proteome microarray, and neutralizing antibody was detected by a pseudotyped virus neutralization assay system. The dynamics of antibodies were analyzed with exposure time or symptoms onset.

Results

A combination test of NAT and serological testing for IgM antibody discovered 55.5% of the total of 63 asymptomatic infections, which significantly raises the detection sensitivity when compared with the NAT alone (19%). Serum proteome microarray analysis demonstrated that asymptomatics mainly produced IgM and IgG antibodies against S1 and N proteins out of 20 proteins of SARS-CoV-2. Different from strong and persistent N-specific antibodies, S1-specific IgM responses, which evolved in asymptomatic individuals as early as the seventh day after exposure, peaked on days from 17 days to 25 days, and then disappeared in two months, might be used as an early diagnostic biomarker. 11.8% (6/51) mild patients and 38.1% (24/63) asymptomatic individuals did not produce neutralizing antibody. In particular, neutralizing antibody in asymptomatics gradually vanished in two months.

Conclusion

Our findings might have important implications for the definition of asymptomatic COVID-19 infections, diagnosis, serological survey, public health, and immunization strategies.

     

人胚胎肺内神经内分泌细胞电镜观察

用透射电镜对不同胎龄的人胚胎肺内神经内分泌细胞进行了发生和超微结构观察。肺内支气管上皮内未分化细胞，第八周开始向神经内分泌细胞转化，提示神经内分泌细胞对早期胚胎肺的发生、发育有特殊意义。神经内分泌细胞内致密核心小泡（ＤＣＶ）及其它与内分泌活动有关的各种细胞器发达。能见到Ｐ０细胞、Ｐ１细胞、Ｐ２细胞及Ｐ３细胞等四种类型的神经内分泌细胞。Ｐ０细胞的发生及分化程度表明它可能是一种前细胞，它可以进一步转化     

Evaluation of RGS4 as a candidate gene for schizophrenia.

Several studies have suggested that the regulator of G-protein signaling 4 (RGS4) may be a positional and functional candidate gene for schizophrenia. Three single nucleotide polymorphisms (SNP) located at the promoter region (SNP4 and SNP7) and the intron 1 (SNP18) of RGS4 have been verified in different ethnic groups. Positive results have been reported in these SNPs with different numbers of SNP combinatory haplotypes. In this study, these three SNP markers were genotyped in 218 schizophrenia pedigrees of Taiwan (864 individuals) for association analysis. Among these three SNPs, neither SNP4, SNP7, SNP18 has shown significant association with schizophrenia in single locus association analysis, nor any compositions of the three SNP haplotypes has shown significantly associations with the DSM-IV diagnosed schizophrenia. Our results fail to support the RGS4 as a candidate gene for schizophrenia when evaluated from these three SNP markers.     

钙拮抗剂对出血性休克犬重要器官组织中黄嘌呤氧化酶活性的影响

在休克过程中，体内活性氧代谢与细胞内钙超负荷存在着相互影响。为了研究林克和复苏过程中钙拮抗剂对脂质过氧化的影响，用１７只杂种犬快速放血使平均动脉压为５．３２ｋｐｄ，并维持９０ｍｉｎ。然后回输全部失血。在休克３０ｍｉｎ时，各组别静脉注射（１５ｍｉｎ内）硫氮酮（４０ｇ／ｋｇ·ｍｉｎ￣（－１）），异搏定（１０μｇ／ｋｇ·ｍｉｎ￣（－１）），或等量生理盐水。复苏后１５０ｍｉｎ处死动物，取心、肝、肺、肾、胰和小肠组织备检。结果显示，用硫氮酮和异搏定治疗组，各主要脏器组织中黄嘌呤氧化酶活性和丙二醛含量均显著低于休克对照组。而各检测组织中超氧化物歧化酶活性变化不一。这些资料显示钙拮抗剂抗休克的机制与其阻滞Ｃａ２＋内流，降低组织中黄嘌呤氧化酶活性，抑制脂质过氧化有密切关系。     

血管内皮生长因子和E26转录因子在乳腺癌中的表达及意义

目的 试图揭示血管内皮生长因子（VEGF）和E26转录因子（E26 transformation-specificl,ETS-1)在乳腺癌组织中的表达规律,探讨其在血管生成和肿瘤浸润转移中的作用机制。方法 应用原位杂交和免疫组织化学链霉素抗生物系－过氧化物酶复合物法（SP）法,检测48例乳腺癌组织中VEGF和ETS－1的mRNA和蛋白的表达。结果 乳腺癌细胞高表达VEGF mRNA和蛋白,阳性率分别为75％（36／48）,70．8％（34／48）,而血管内皮细胞几乎不表达;ETS－1既表达在乳腺癌细胞,也表达在血管内皮细胞。癌细胞中mRNA和蛋白表达阳性率分别为85．4％（41／48）,79．2％（38／48）;VEGF和ETS－1高表达组的血管密度明显高于低表达组（均P＜0．01）;VEGF和ETS－1的表达与组织学分级和淋巴结转移密切相关,并且高表达组的微血管密度明显高于低表达组（P＜0．01）。结论 VEGF和ETS－1可促进乳腺癌血管形成,同时也促进肿瘤的浸润和转移;检测VEGF和ETS－1的表达可做为乳腺癌恶性度,浸润转移等生物学行为的参考指标。     

Enhanced activity of GABA receptors inhibits glutamate release induced by focal cerebral ischemia in rat striatum

Cerebral ischemia causes an excess release of glutamate, which can injure neurons. The striatum is one of the important regions vulnerable to hypoxia and ischemia. Using push–pull perfusion technique, we investigated the regulatory role of γ-aminobutyric acid (GABA) and its receptors in modifying the amount of glutamate in rat striatum with ischemia. Perfusion with exogenous GABA (1 mM) inhibited cerebral ischemia-induced glutamate release by as much as 47%. We further characterized relative roles of subtype receptors of GABA on glutamate release by using pharmacological tools. While baclofen (500 μM), a GABA_B receptor agonist, suppressed ischemia-induced glutamate release by 52%, GABA_B receptor antagonist saclofen (500 μM) failed to produce a significant increase of glutamate release. The GABA_A receptor agonist muscimol (500 μM) also reduced by 38% the release of glutamate induced by cerebral ischemia but the GABA_A receptor antagonist bicuculline (500 μM) had very little effect. The present study demonstrates that the excessive release of glutamate or the overly activated glutamate receptor, triggered by cerebral ischemia, can be down-regulated by exogenous GABA or by increased activity of GABA receptors, especially the presynaptic GABA_B receptors, which might be one of the important mechanisms to protect against striatum neuronal damage from over stimulation by excessive glutamate during ischemia.