Use of the microorganism Bacillus stearothermophilus as a model to evaluate toxicity of the lipophilic environmental pollutant endosulfan.

Microorganisms are very powerful tools for the supply of information about the toxic effects of lipophilic compounds, since an impairment of cell growth usually occurs as a result of perturbations related, in most cases, with the partition of toxicants in membranes. The thermophilic eubacterium Bacillus stearothermophilus has been used as a model system to identify - and β-endosulfan interactions with the membrane possibly related with the insecticide toxicity. Two approaches have been pursued: (a) bacterial growth is followed and the effects of endosulfan isomers determined; (b) biophysical studies with the fluorescent fluidity probe 1,6-diphenyl-1,3,5-hexatriene (DPH) were performed to assess the effects of - and β-endosulfan on the organization of the membrane lipid bilayer. The effects on growth were quantitatively evaluated by determination of growth parameters, namely the lag phase, the specific growth rate and the cell density reached by cultures in the stationary phase. Growth inhibition by and β-endosulfan dependent on the concentration is diminished or removed by the addition of 2.5 m Ca²⁺ to bacterial cultures. Fluorescence DPH polarization consistently showed opposite effects of Ca²⁺ and - and β-endosulfan on the physical state of bacterial polar lipid dispersions.     

天狼星红染色法结合图像分析在放射性肺纤维化研究中的应用

应用天狼星红染色切片进行偏振光显微镜观察，可明确地区分Ⅰ、Ⅲ型胶原并显示两型胶原在肺组织中的分布及其变化规律，配合图像分析法，可以测定不同剂量照射后三个月各组肺内Ⅰ、Ⅲ型胶原纤维的比值变化；将这一方法与肺组织羟脯氨酸含量测定相比较，表明二者在显示肺纤维化程度和变化趋势上具有相同的结果。     

肺泡巨噬细胞对肺气虚证局部神经—内分泌—免疫系统功能影响

检测４０例慢性支气管炎肺气虚证、３９例慢支隐性肺证患者及３６例正常人外周血、支气管肺灌洗液（ＢＡＬＦ）Ｔ淋巴细胞亚群（ＯＫＴ８）、皮质醇及去甲肾上腺素以及肺泡巨噬细胞（ＡＭ）分泌ＴＸＢ２／ＰＧＦ１ａ。结果表明：肺气虚证局部ＮＥＩＳ紊乱较明显，它与ＡＭ分泌的ＴＸＢ２和ＰＧＦ１ａ有关。隐性肺证局部病理生理变化较轻，局部与整体ＮＥＩＳ功能相互作用，尤其是整体对局部的调节稳定作有更加明显，而ＡＭ产生炎症介质对局部ＮＥＩＳ破坏的作用相对减弱     

神经节苷脂GM3,GD3对小鼠巨噬细胞介导的细胞毒作用的影响

目的观察外源性神经节苷脂ＧＭ３、ＧＤ３对人肝癌ＳＭＭＣ┐７７２１细胞的杀伤活力的影响。方法应用３Ｈ┐ＴｄＲ掺入法测定ＧＭ３、ＧＤ３对巨噬细胞的细胞毒作用的影响。结果ＧＭ３、ＧＤ３对巨噬细胞短时间（４５分钟）作用后，两者都对细胞毒产生双相调节，但两者调节作用相反。ＧＭ３、ＧＤ３对巨噬细胞长时间（２４小时）作用后，两者均抑制细胞毒作用，ＧＤ３的抑制作用更强。结论ＧＭ３、ＧＤ３作用于巨噬细胞后对其杀伤ＳＭＭＣ┐７７２１细胞的细胞毒作用产生不同程度的抑制，提示两者在巨噬细胞介导的宿主免疫监视和免疫破坏中发挥作用     

口腔鳞癌中单核细胞趋化蛋白-1在巨噬细胞浸润、聚集中的意义

目的:探讨口腔鳞癌中单核细胞趋化蛋白-1(monocyte chemoattractant protein-1 MCP-1)表达与肿瘤中浸润巨噬细胞的关系.方法:应用免疫组化方法检测口腔鳞癌中MCP-1的表达和巨噬细胞的浸润,光镜进行高倍视野下巨噬细胞记数和MCP-1表达的分级.结果:在口腔鳞癌中MCP-1的表达与肿瘤分化有关,并与肿瘤内浸润的巨噬细胞有关(P＜0.05).结论:巨噬细胞可能受MCP-1趋化作用的影响,参与肿瘤的生长和转移.     

贝叶斯法估算丙戊酸药动学参数及个体化给药

目的:采用癫痫患者丙戊酸群体药动学参数结合贝叶斯(Bayesian)法估算癫痫患者丙戊酸的个体药动学参数;制定或优化欲达预期血药浓度所应实施的给药方案,使癫痫患者丙戊酸给药有效、合理、毒副作用小.方法:癫痫患者口服丙戊酸达稳态,取其每天早晨服药前10 min血样57人次,用荧光偏振免疫法(Fluorescence Polarization Immunoassay,FPIA)测得血清中丙戊酸和游离丙戊酸血药浓度谷值.用Bayesian法估算其药动学参数,并用逐步回归法分析个体的性别、年龄等18种因素对其药动学参数的影响.结果:按口服一房室一级吸收和消除的开放模型用Bayesian法估算得丙戊酸药动学参数清除率CL,平均值为(8.7±0.6)mL·h-1·kg-1,逐步回归方程:CL(mL·h-1·kg-1)=3.972 1.631X5 1.608X11;稳态血药浓度谷值Cp0逐步回归方程:Cp0(mg·L-1)=57.58-0.71X4-12.145X5 2.705X7 0.403x17.式中X4表示体重(kg),X5表示身高(cm)体重(kg)比,X7表示每日每千克体重的给药剂量(mg·d-1·kg-1),x11表示当合并用苯妥英钠时系数为1,否则为0,x17表示血清肌酐(μmol·L-1).实测丙戊酸稳态血药浓度谷值(52.4±5.4)mg·L-1与估算值(53.5±5.2)mg·L-1间差异无统计学意义,P＞0.05.结论:可采用Bayesian法估算癫痫患者丙戊酸动力学参数和进行个体化给药的拟定或调整给药方案.     

儿童丙戊酸群体药动学

目的:研究仅有临床稀疏数据的儿童丙戊酸群体药动学.方法:收集667例儿童癫痫患者的常规治疗药物监测资料,将794对血药浓度-时间数据利用群体药动学理论经CPKDP程序处理,提取儿童群体药动学参数,再经Bayesian反馈法及二步迭代计算出儿童个体药动学参数.结果:儿童丙戊酸群体药动学主要参数Ke、Vm、CL在单用丙戊酸组分别为(4.5±2.2)h-1、(1.4±0.5)L·kg-1和(14.5±4.3)mL·h-1·kg-1;在合并其他抗癫痫药物时分别为(7.3±3.4)h-1、(1.4±0.6)L·kg-1、(24.8±9.3)mL·h-1·kg-1.预测浓度和实测浓度显著相关;合并PB、PTH、CBZ、CNP对丙戊酸的药动学有显著影响.结论:本研究对儿童丙戊酸给药方案个体化提供有价值的参考依据.     

矽肺肺泡巨噬细胞对肺成纤维细胞基质金属蛋白酶及其组织抑制因子表达的影响

目的 探讨矽肺患者的肺泡巨噬细胞(AM)是否通过影响肺成纤维细胞(FB)基质金属蛋白酶(MMPs)/金属蛋白酶组织抑制因子(TIMPs)系统参与矽肺纤维化的发生发展。方法 收集矽肺患者AM培养上清,与人胚肺FB共同孵育6、12、18、24、36、48 h,用免疫细胞化学的方法检测FB中MMP-1和TIMP-1的表达。结果 未经SiO2刺激的矽肺患者AM培养上清作用于FB 24 h,FB中MMP-1的表达较空白对照组减少(积分光密度值分别为0.103±0.014、0.133±0.023),TIMP-1的表达增多(积分光密度值分别为0.108±0.012、0.065±0.006);经SiO2刺激24 h的矽肺患者AM培养上清作用于FB后,FB中MMP-1的表达量进一步减少(积分光密度值分别为0.062±0.008、0.133±0.023),而TIMP-1的表达量进一步增加(积分光密度值分别为0.143±0.015、0.065±0.006)。结论 SiO2可能通过AM的介导影响了FB中MMP-1/TIMP-1系统的表达,参与了肺纤维化的形成。     

寡核苷酸表达谱揭示异烟肼耐药对结核分支杆菌致病性的影响

目的研究结核分支杆菌异烟肼耐药菌株与H37Rv异烟肼敏感菌株感染巨噬细胞后差异表达的基因. 方法利用高密度cDNA芯片检测巨噬细胞U937感染结核分支杆菌异烟肼耐药菌株与H37Rv后的基因表达谱的差异. 结果两者诱导巨噬细胞的差异表达基因有53条,异烟肼耐药菌株比敏感菌株诱导多种趋化因子和细胞免疫增强的细胞因子表达上调和免疫抑制细胞因子IL-10等表达下调. 结论异烟肼耐药对细菌毒力有明显的影响,异烟肼耐药菌株的致病力下降,异烟肼耐药菌株容易被宿主免疫系统清除;结果为耐多药结核病控制提供依据;骨桥接素和巨噬细胞趋化因子等,在抗异烟肼耐药结核分支杆菌感染免疫中的作用值得深入研究.     

Expression and characterization of αvβ5 integrin on intestinal macrophages

Macrophages play a crucial role in maintaining homeostasis in the intestine, but the underlying mechanisms have not yet been elucidated fully. Here, we show for the first time that mature intestinal macrophages in mouse intestine express high levels of αvβ5 integrin, which acts as a receptor for the uptake of apoptotic cells and can activate molecules involved in several aspects of tissue homeostasis such as angiogenesis and remodeling of the ECM. αvβ5 is not expressed by other immune cells in the intestine, is already present on intestinal macrophages soon after birth, and its expression is not dependent on the microbiota. In adults, αvβ5 is induced during the differentiation of monocytes in response to the local environment and it confers intestinal macrophages with the ability to promote engulfment of apoptotic cells via engagement of the bridging molecule milk fat globule EGF‐like molecule 8. In the absence of αvβ5, there are fewer monocytes in the mucosa and mature intestinal macrophages have decreased expression of metalloproteases and IL 10. Mice lacking αvβ5 on haematopoietic cells show increased susceptibility to chemical colitis and we conclude that αvβ5 contributes to the tissue repair by regulating the homeostatic properties of intestinal macrophages.