组织因子途径抑制因子重组蛋白表达和纯化方法的优化

目的:对组织因子途径抑制因子(TFPI)的表达条件和纯化方法进行优化,降低重组蛋白制备成本.方法:应用巴斯德毕赤酵母表达系统进行TFPI重组蛋白的表达.采用不同浓度甲醇进行重组蛋白表达诱导,观察不同pH对重组蛋白活性的影响,应用硫酸铵分级沉淀、阴离子交换层析和凝胶过滤层析相结合的方法纯化重组蛋白.结果:重组蛋白的表达量达到1.5 mg/L培养基.上述蛋白纯化方法所得回收率为43.1%,蛋白纯度大于95%,蛋白活性保持良好.结论:优化后的蛋白表达量比优化前得到明显提高,本研究采用的纯化方法操作简单、耗时短、成本低且回收率较高.     

气相色谱法测定太子参中有机氯农药残留量

[目的]观察太子参主产地的太子参被有机氯农药的污染情况.[方法]采用气相色谱一电子捕获检测(GC-ECD)法,对全国各主产地的10批太子参样品的有机氯农药残留量进行了检测.[结果]各主产地太子参受有机氯农药污染比较普遍,其中某些样品总六六六(BHC)和总滴滴涕(DDT)残留量较高,超过了我国外贸行业<药用植物及制剂进出...     

Dynorphin and prodynorphin mRNA changes in the striatum during nicotine withdrawal

Nicotine withdrawal causes somatic and negative affective symptoms that contribute to relapse and continued tobacco smoking. So far, the neuronal substrates involved are not fully understood, and an opioid role has been suggested. In this regard, the opioid dynorphin (Dyn) is of interest as it produces aversive states and has been speculated to play a role in the nicotine behavioral syndrome. These studies explore whether Dyn metabolism is altered during withdrawal following chronic administration of nicotine. Mice were administered nicotine, 2 mg/kg, s.c., four times daily for 14 days, and Dyn and prodynorphin (PD) mRNA estimated in selective brain regions at various times (30 min to 96 h) following drug discontinuation. The content of Dyn, estimated by RIA, was decreased in the striatum for a protracted time, from 30 min to over 72 h. In contrast, the mRNA for PD, evaluated by Northern blot, was elevated, appearing by 8 h and lasting over 96 h. Dyn was decreased in both ventral and dorsal striatum, and PD mRNA was differentially increased in the two striatal compartments as demonstrated by in situ hybridization. PD message was predominantly augmented in the nucleus accumbens, rostral pole, core, and shell, and the medial aspects of caudate/putamen. We interpret these data to indicate increased activity of striatal, particularly accumbal, dynorphinergic neurons during nicotine withdrawal resulting in enhanced peptide release and compensatory synthesis. Heightened dynorphinergic tone might be responsible, in part, for the emergence of the negative affective states observed during nicotine withdrawal.     

十二指肠乳头旁憩室内Dieulafoy病变合并出血1例(含视频)

十二指肠乳头旁憩室内Dieulafoy病变合并出血因病灶隐匿、临床表现不典型、缺乏特异性症状, 内镜下较难发现。本文报道1例十二指肠乳头旁憩室内Dieulafoy病变合并出血病例的内镜下诊治过程。     

何首乌炮制与肝毒性研究进展

何首乌及其炮制品为临床常用中药,对人体有多种有益效果。临床服用何首乌引起肝中毒问题时有报道,但由于何首乌导致肝毒性的机制尚未完全明确,炮制后的何首乌仅被认为是相对安全,目前仍缺乏有效控制何首乌炮制品的科学方法。本文从何首乌的炮制工艺、化学成分、肝毒性、药代动力学等角度汇总分析何首乌研究进展,以探索何首乌质量控制方法和下一步研究思路。     

经胸右心声学造影预估肝硬化伴食管胃底静脉曲张内镜下治疗效果的初步研究

目的探讨经胸超声心动图（TTE）和经胸右心声学造影（Ｃ-TTE）对肝硬化伴食管胃底静脉曲张内镜下治疗效果是否有预测价值。 方法前瞻性选取2020年5月至2021年3月在四川省人民医院行首次食管胃底静脉曲张内镜下治疗并完成完整随访的26例肝硬化失代偿期患者。根据内镜下序贯治疗次数将患者分为2组：治疗次数≥3次或转介入、外科手术治疗的为内镜下治疗效果不佳组（14例）;治疗次数＜3次的为内镜下治疗效果良好组（12例）。比较分析2组患者的一般资料、术前生化指标、食管胃底静脉曲张及治疗情况,以及术前TTE和C-TTE参数。 结果治疗效果良好组与治疗效果不佳组术前生化指标、TTE参数比较,差异均无统计学意义（P均＞0.05）。2组患者食管静脉曲张范围比较,差异存在统计学意义（P＜0.05）,2组均以中下段食管静脉曲张占比最多,治疗效果不佳组该比例更高（85.71% vs 41.67%）。术前C-TTE显示治疗效果不佳组有78.57%存在右向左分流（RLS）（心内水平2例,心外水平8例,心内合并心外1例）,中量及以上占比达50.00%;而治疗效果良好组仅33.33%存在RLS（心内水平1例,心外水平3例）,中量及以上占比约16.67%。治疗效果不佳组RLS的发生率高于治疗效果良好组（χ²=5.418,P=0.020）,中量及以上分流量占比也高于治疗效果良好组。 结论通过C-TTE明确是否伴发心内和（或）心外水平RLS,可能有助于预测肝硬化伴食管胃底静脉曲张内镜下治疗的效果,C-TTE对其治疗效果预估可能有一定指导价值。     

Targeting serum antibody for cancer diagnosis: a focus on colorectal cancer

The ability of the immune system to magnify the appearance of disease by generating relatively large amounts of antibody in response to small amounts of disease makes it a natural biosensor, and serum antibodies have emerged as promising biomarkers for the detection of cancer. This review summarizes recent progress in targeting serum antibodies for cancer diagnosis, with a particular focus on colorectal cancer (CRC). Several serum antibodies have been detected at increased levels in CRC patients, including p53, carcinoembryonic antigen, Ras, topoisomerase II-alpha, histone deacetylase 3 and 5, ubiquitin C-terminal hydrolase L3, tropomyosin and cyclin B1. As each antibody is only present in a limited proportion of patients (usually < 40%), a combination of serum antibodies that defines the 'immunological signature' of cancer needs to be developed. High-throughput methods to identify new serum antibodies for cancer diagnosis are also reviewed.     

Activation of mitogen-activated protein kinase by muscarinic receptors in astroglial cells: role in DNA synthesis and effect of ethanol.

Mitogen-activated protein kinase (MAPK) can be phosphorylated by mitogens binding to G-protein-coupled receptors and is considered a major pathway involved in cell proliferation. In this study, we report on the activation of MAPK by muscarinic acetylcholine receptors in astroglial cells, namely the 1321N1 human astrocytoma cell line, primary rat cortical astrocytes, and fetal human astrocytes. Carbachol caused a rapid and transient phorphorylation of MAPK (ERK1/2) in all cell types, with an increase in MAPK activity, without changing the levels of MAPK proteins. Human astrocytoma cells were used to characterize the effect of carbachol on MAPK. Experiments with M2- and M3-receptor subtype-selective antagonists, and with pertussis toxin, indicated that the M3 subtype is responsible for activating MAPK in glial cells. Pretreatment of cells with the protein kinase C (PKC) inhibitor bisindolylmaleimide I, or downregulation of PKC by 24-h treatment with the phorbol ester TPA inhibited carbachol-induced MAPK activation. Additional experiments with PKC alpha- or PKC epsilon-specific compounds indicated that the epsilon isozyme of PKC is primarily involved in MAPK activation by carbachol. Chelation of calcium also inhibited MAPK activation by carbachol. Two MEK (MAPK kinase) inhibitors inhibited carbachol-induced DNA synthesis but only at concentrations that exceeded those sufficient to block carbachol-induced MAPK activation. Ethanol (< or =200 mM) had no effect on MAPK when present alone and did not affect carbachol-induced MAPK activation under various experimental conditions, although it inhibits carbachol-induced DNA synthesis at low concentrations (10-100 mM). These results suggest that activation of MAPK by carbachol may be necessary but not sufficient for its mitogenic effect in astroglial cells, and that does not represent a target for ethanol-induced inhibition of DNA synthesis elicited by muscarinic receptors.