小鼠耳蜗核因子-κB p50免疫组化定位

目的 了解核因子-κB(NF-κB)在耳蜗的表达情况.方法 小鼠皮下注射卡那霉素(KA),鼓室注射脂多糖(LPS),以注射等量生理盐水作为对照,用多克隆兔抗体NF-κB p50免疫组化染色,观察NF-κB p50在小鼠耳蜗的表达.结果 NF-κB p50主要定位在耳蜗的螺旋缘、盖膜、血管纹、螺旋韧带、螺旋神经节和神经纤维.整个耳蜗各圈均可观察到免疫反应,而螺旋韧带、盖膜、螺旋突、螺旋神经节和神经纤维均可观察到较强的免疫反应,Corti器的免疫反应比上述结构要弱一些.Corti器的内、外毛细胞,内、外柱细胞,Deiter细胞和Claudious细胞均可观察到NF-κB p50的免疫反应,这些免疫反应在内沟细胞、Hensen细胞和Claudious细胞较弱,而在螺旋神经节可观察到较强的免疫反应,内、外毛细胞核未见免疫反应.结论 注射脂多糖和卡那霉素可使NF-κB p50在小鼠耳蜗产生急性反应.     

Structure-acute toxicity relationship of aromatic hydrocarbons in mice

The structure-acute toxicity relationship of aromatic hydrocarbons was examined in mice. In all test compounds, the acute toxicity was determined under 2 conditions: control LD₅₀ (LD₅₀-cont) and carbon tetrachloride (CCl₄)-pretreated LD₅₀ (LD₅₀-CCl₄). The CCl₄-pretreatment was done in order to evaluate the toxic potency of compound itself without the influence of metabolism. Both log (1/LD₅₀-cont) and log (1/LD₅₀-CCl₄) were functions of the log P, n-octanol/water partition coefficient, i.e., log (1/LD₅₀-cont) = 0.080 log P − 1.532 and log (1/LD₅₀-CCl₄) = −0.040(log P)² + 0.157 log P − 1.373. Both equations were statistically significant (P < 0.01). The ratio of LD₅₀-cont/LD₅₀-CCl₄ indicated that metabolic activation is more evident in hydrophobic compounds than in hydrophilic compounds. The results suggest that hydrophobicity of the aromatic hydrocarbons plays an important role in determining their acute toxicity.     

-Hydroperoxy diethyl peroxide, an unusual natural compound isolated from an ascidian (Phallusia mammillata): acute toxicity in DDY mice

-Hydroperoxy diethyl peroxide, a novel compound found in the tunic of ascidians, has two peroxide moieties per molecule. Since ascidians are a widely served food item in Japan, human exposure to this compound potentially exists in the seafood preparation industries. No toxicological data have so far been published on this compound, and so we determined the intraperitoneal 6-day LD₅₀ in mice and conducted histopathological examinations. The 6-day LD₅₀, was found to be 199 mg/kg with 95% confidence limits of 126–314 mg/kg. Histopathological examination revealed necrosis induced in a variety of cells that had been directly exposed to the compound. These cells included hepatocytes, parenchymal pancreatic cells and fat cells. It is concluded that direct contact with this compound is likely to elicit cellular necrosis of various organs. The specific toxicological effects are probably dependent on the route of exposure.     

CA-199、CA-50联检对消化道肿瘤的诊断价值评价

目的 :探讨糖类抗原CA -199及CA -5 0联合检测对消化道恶性肿瘤诊断的临床价值。方法 :用化学发光及免疫放射方法检测 5 0例健康者 ,88例消化道良性疾病及 91例消化道恶性肿瘤患者血清中CA -199及CA -5 0的含量。结果 :消化道恶性肿瘤患者血清CA -199、CA -5 0值均明显高于正常健康人及消化道良性疾病 ,两者比较有显著性差异 (P <0 0 1) ,CA -199、CA -5 0两者联合检测较单项检测任何一项其阳性率、准确率均有明显提高。结论 :CA -199、CA -5 0联检可为临床减少漏诊、误诊 ,为早诊早治提供有价值的信息     

45例正常人听觉诱发电位P50的分析

目的 利用诱发电位技术探讨正常人听觉P50特征.方法 应用美国Nicolet Bravo脑电生理仪,采用条件刺激(S1)-测试刺激(S2)模式对45名健康受试者作了听觉P50检测.结果 分析了基本波型,提出了Cz和Pz区域P50诸指标平均值.结论 听觉P50电位具有抑制性特征,其变化可反映大脑正常感觉门的功能状态.P50较佳表达式是波幅S1-S2和100(1-S2/S1)两种结合,能直接显示感觉门的程度.此正常值可供抑郁症研究时参考.     

K562／ADM耐药细胞株的建立及其生物学特性的初步观察

我们建立的K562/ADM耐药细胞株,在ADM浓度为2.4μg/m1(4.46μM)中已稳定培养3.5个月,传了30—35代,K562/ADM亦具有多药耐受件(Multidrug Resistance,MDR)的特点,对ADM、VCR、AT—1258和DDP的耐受性分别为K562的114.7、94.0、13.3和7.4倍,但对5—FU不产生交叉耐药。K562和K562/ADM的倍增时间分别为19.2h和52.8h,集落生成率分别为37.5％和11.1％,K562染色体数为34—68,中位数为56;K562/MDM染色体数为32—90,中位数为50,K562/ADM可做为耐药机理和克服耐药措施研究的极好模型。     

Flecainide

Flecainide. Flecainide is a Class IC antiarrhythmic agent whose primary electrophysiologic effect is a slowing of conduction in a wide range of cardiac tissues. It is well absorbed and effective in suppressing isolated premature ventricular contractions (PVCs) or nonsustained ventricular arrhythmia but has only a modest efficacy when electrophysiologic testing is used as an endpoint. Us adverse effect on mortality in the CAST trial suggested a propensity to proarrhythmia-a phenomenon to which the Class IC agents appear particularly prone. Despite the applicability of the CAST study only to patients with a prior myocardial infarction, there has been a shift away from flecainide in ventricular arrhythmia, but the low noncardiac side effect profile of the agent allows for its continued use in a wide variety of supraventricular arrhythmias. ( J Cardiovasc Electrophysiol, Vol. 5, pp. 964–981. November 1994 )     

The monoclonal antibody Alz-50, used to reveal cytoskeletal changes in Alzheimer's disease, also reacts with a large subpopulation of somatostatin neurons in the normal human hypothalamus and adjoining areas

The monoclonal antibody Alz-50 is directed against Alzheimer's disease-related modified tau proteins and reveals cytoskeletal changes, i.e. neurofibrillary tangles and dystrophic neurites. The present study shows that, in the hypothalamus of non-demented control subjects, this same antibody gives a distinctive staining pattern of a subpopulation of somatostatin neurons and beaded fibers. Furthermore, Alz-50 occasionally recognizes somatostatin-containing cell bodies and dystrophic neurite-like fibers in the (neuritic) senile plaques of AD patients. These observations have direct consequences for the interpretation of Alz-50 staining in diagnostic usage and for the assessment of Alzheimer's disease-like changes induced by β-amyloid in experimental animal brains. On dot spotting, Alz-50 was found to bind to a number of fragments from the somatostatin precursor, of which somatostatin_15–28 stained best. Preadsorption of Alz-50 by somatostatin_15–28, as well as other specificity tests, failed, however, to provide any clue to the nature of the unknown compound(s) stained in the control hypothalamus.     

雷米芬太尼呼吸抑制的半数有效血浆浓度的临床研究

目的测定靶控输注雷米芬太尼引起呼吸抑制的半数有效血浆浓度(Cp50)。方法20例择期手术病人行椎管内阻滞。按序贯法给予雷米芬太尼靶控输注20min,相邻血浆靶浓度之间比率为1·5。测定RR、SpO2、PETCO2及动脉血气。结果雷米芬太尼引起呼吸抑制的Cp50为1·8μg/L,95%可信区间为1·5~2·1μg/L。结论雷米芬太尼引起呼吸抑制的Cp50为1·8μg/L。     

Infection dynamics and virus-induced apoptosis in cell culture-based influenza vaccine production—Flow cytometry and mathematical modeling

Cell culture-based influenza vaccine manufacturing is of growing importance. Depending on virus strains, differences in infection dynamics, virus-induced apoptosis, cell lysis and virus yields are observed. Comparatively little is known concerning details of virus–host cell interaction on a cellular level and virus spreading in a population of cells in bioreactors. In this study, the infection of MDCK cells with different influenza A virus strains in lab-scale microcarrier culture was investigated by flow cytometry. Together with the infection status of cells, virus-induced apoptosis was monitored. A mathematical model has been formulated to describe changes in the concentration of uninfected and infected adherent cells, dynamics of virus particle release (infectious virions, hemagglutinin content), and the time course of the percentage composition of the cell population.