牛磺酸对顺铂引起的原代培养兔肾小管上皮细胞膜流动性的影响

目的 :研究顺铂对培养的兔原代肾小管上皮细胞膜流动性的改变以及牛磺酸对肾小管上皮细胞膜的保护作用。方法 :采用体外培养兔肾小管上皮细胞 ,顺铂损伤组用不同浓度的顺铂与肾小管上皮细胞共同孵育24h ,牛磺酸保护组用不同浓度牛磺酸预先与肾小管上皮细胞孵育24h ,然后再加入顺铂 (26μmol/L)共同孵育24h ,用DPH荧光探剂法测定细胞膜流动性。结果 :顺铂13、26、52μmol/L能导致肾小管上皮细胞荧光偏振度 (P) ,各向异性 (γ)和微粘度 (η)显著下降 (P<0.01) ,牛磺酸在10g/L时可逆转顺铂导致的P、γ和 η 的下降 (P<0.05)。结论 :顺铂可引起体外培养的兔肾小管上皮细胞膜流动性增加 ,牛磺酸可降低膜流动性 ,具有膜稳定性。     

谷胱甘肽对顺铂致大鼠肾小管上皮细胞毒性的影响

目的 探讨顺铂对不同年龄大鼠肾小管上皮细胞的毒性及谷胱甘肽(GSH)对其影响。方法 从不同年龄的雄性大鼠分离的肾小管上皮细胞接种于96孔培养板，培养24h后加入一系列浓度的顺铂，或在加入顺铂前16和4h。分别加入GSH合成抑制剂：BSO和GSH的前体物半胱氨酸，再培养24h后用MTT方法检测细胞存活率。结果 顺铂对5、2月龄和3周龄大鼠肾小管上皮细胞半数抑制浓度(IC50)分别为243．42、178．16和159．06μmol／L；BSO能使3组IC50分别降低到1．62、1．30和1．47μmol／L，而半胱氨酸则可使3组IC50均大于5000μmol／L。结论 顺铂对不同年龄大鼠肾小管上皮细胞均具有明显的毒性，BSO和半胱氨酸可分别增强和减弱顺铂的毒性，间接证明细胞内GSH对顺铂所致大鼠肾小管上皮细胞毒性有保护作用。     

谷胱甘肽对顺铂致猴和大鼠肾细胞毒性的影响

目的 探讨顺铂对猴和大鼠肾小管上皮细胞的毒性及半胱氨酸和GSH合成抑制剂BSO对其影响。方法 从猴和大鼠的肾脏分离培养的肾小管上皮细胞接种于96孔培养板，培养24h后加入一系列浓度的顺铂，或在加入顺铂前16和4h，分别加入GSH合成抑制剂BSO和GSH的前体物半胱氨酸，继续培养，分别在8、24和48h3个时间点用MTT方法检测细胞存活率。结果 顺铂对猴和大鼠肾小管上皮细胞有明显的毒性，在不同的时间点有各自的剂量—反应关系，顺铂对大鼠肾小管上皮细胞在8、24和48h 3个时间点半数抑制浓度(IC50)分别为1105．12、513．25和71．24μmol/L；BSO能使3组IC50均降低，分别为66．00、21．43和7．23μmol/L，而半胱氨酸则使3组IC50均升高，均大于5000μmol/L；顺铂对猴肾小管上皮细胞在3个时间点IC50分别为3026．00、1238．35和664．44μmol/L；BS0使3组ICD分别降为480．10、108．61和31．43μmol/L，而半胱氨酸则可使3组IC50均大于5000μmol/L。结论 顺铂对猴和大鼠肾小管上皮细胞均具有明显毒性作用，对猴的毒性低于大鼠；BS0可增强顺铂的细胞毒性，对大鼠的影响大于猴，而半胱氨酸对两种细胞的保护作用无显著性差异，提示细胞内GSH对顺铂所致肾小管上皮细胞毒性有保护作用。     

顺铂对原代培养兔近端肾小管上皮细胞酶活力的影响以及牛磺酸 …

目的 研究顺铂对原代培养的近端肾小管上皮细胞（ＰＴＣ）的乳酸脱氢酶（ＬＤＨ）,碱性磷酸酶（ＡＬＰ）,Ｎ－乙酰－β－氨基葡萄糖苷酶（ＮＡＧ）活力的影响,探讨牛磺酸,三七皂苷,茵陈素对酶活力的保护作用。方法 在体外建立ＰＴＣ。顺铂损伤组,顺铂与ＰＴＣ共同保温２４ｈ;处理组,牛磺酸,三七皂苷,茵陈素提前与ＰＴＣ作用２４ｈ,后再加入顺铂共同保温２４ｈ,。结果 右铂（１３,２５６,５２,７８,１０４μｊｏｌ     

氟伐他汀干预血管紧张素Ⅱ对肾小管上皮细胞分泌纤维连接蛋白的作用

目的 观察血管紧张素Ⅱ(AngⅡ)及氟伐他汀对体外培养的肾小管上皮细胞分泌细胞外基质成分的影响.方法 用10-6mol/L AngⅡ刺激肾小管上皮细胞6、12、24、48、72、96 h,不同浓度(10-9～10-5 mol/L)氟伐他汀干预48 h,免疫印迹及细胞免疫荧光法检测纤维连接蛋白(FN)的表达.结果 AngⅡ刺激体外培养的肾小管上皮细胞12 h后FN表达开始增加,72 h到达高峰.氟伐他汀干预组与AngⅡ刺激(未干预)组比较,FN表达明显下降,浓度10-5 mol/L下降最明显,10-6 mol/L次之,10-7～10-9 mol/L抑制作用没有明显的差别.结论 AngⅡ促进肾小管上皮细胞产生FN,具有一定的时间依赖性,而氟伐他汀能够抑制此作用,并在一定范围内呈浓度依赖.     

血管紧张素Ⅱ对肾小管上皮细胞增殖的影响

目的观察血管紧张素Ⅱ(AngⅡ)对体外培养的肾小管上皮细胞生长的影响。方法用不同浓度(10-6、10-7、10-8、10-9mol/L)AngⅡ刺激体外培养的肾小管上皮细胞,在不同的时间点(24、48、72h)用四甲基偶氮唑盐(MTT)法检测细胞增殖;用不同浓度(10-6、10-7、10-8mol/L)AngⅡ刺激体外培养的肾小管上皮细胞,作用48h后,流式细胞仪检测细胞周期。结果MTT法检测结果显示AngⅡ作用于肾小管上皮细胞后,吸光度(A)值明显增加(P<0.05),10-6mol/LAngⅡ作用后上升最明显(P<0.01),且在48h作用点达到峰值。流式细胞仪结果显示AngⅡ能使肾小管上皮细胞在S期比例增加,DNA合成增加。结论AngⅡ刺激肾小管上皮细胞增殖,48h增殖作用最显著,并在一定范围内呈浓度依赖性。     

顺铂对原代培养兔近端肾小管上皮细胞酶活力的影响以及牛磺酸、三七皂苷和茵陈素的保护作用

目的　研究顺铂对原代培养的近端肾小管上皮细胞（ＰＴＣ）的乳酸脱氢酶（ＬＤＨ）,碱性磷酸酶（ＡＬＰ） ,Ｎ 乙酰 β 氨基葡萄糖苷酶（ＮＡＧ） 活力的影响,探讨牛磺酸,三七皂苷,茵陈素对酶活力的保护作用。方法　在体外建立ＰＴＣ。顺铂损伤组：顺铂与ＰＴＣ共同保温２４ ｈ ;处理组：牛磺酸,三七皂苷,茵陈素提前与ＰＴＣ作用２４ ｈ,后再加入顺铂（２６ μｍｏｌ·Ｌ－ １）共同保温２４ ｈ。结果　顺铂（１３,２６,５２ ,７８,１０４ μｍｏｌ·Ｌ－ １）抑制ＬＤＨ,ＡＬＰ,和ＮＡＧ的活力（ Ｐ＜０－０１）,牛磺酸（１,１０ ｇ·Ｌ－ １） 和茵陈素（４ ,８ ｍｇ·Ｌ－１） 可提高被顺铂抑制的ＬＤＨ、ＡＬＰ和ＮＡＧ 活力（ Ｐ＜ ０－０１） ,三七皂苷（１０ ,１００ ｍｇ·Ｌ－ １）可提高被顺铂抑制的ＬＤＨ 和ＮＡＧ活力（ Ｐ＜ ０－０１ , Ｐ＜０－０５） ,但不能提高ＡＬＰ 活力。结论　顺铂抑制ＰＴＣ 的ＬＤＨ,ＡＬＰ,ＮＡＧ 活力,牛磺酸和茵陈素可提高被顺铂抑制的ＬＤＨ,ＡＬＰ,ＮＡＧ 活力,三七皂苷可提高被顺铂抑制的ＬＤＨ,ＮＡＧ 活力,但不能提高ＡＬＰ活力     

地塞米松诱导肺癌细胞的顺铂耐药及其性别差异

目的：探讨地塞米松是否诱导肺癌细胞对顺铂耐药。方法：采用肺癌细胞株A1和26例肺癌患者手术标本分离的肺癌细胞。用不同浓度地塞米松体外诱导培养24 h后,加入不同浓度顺铂继续培养48 h,用MTT法检测细胞的存活率。结果：A1细胞株经地塞米松诱导后,对顺铂呈现典型的耐药,与地塞米松浓度呈剂量依赖关系;男性患者肺癌细胞1例呈现耐药（1/26,3.8%）,女性4例耐药（4/26,15.4%）,二者呈显著性差异（P〈0.01）。结论：体外实验结果表明,地塞米松对多数肺癌患者的肿瘤细胞不诱导顺铂抗性。女性患者的肺癌细胞中经地塞米松诱导后耐药比率高于男性患者。     

茵陈素减弱顺铂导致原代兔肾小管上皮细胞DNA链间交联和DNA-蛋白交联(英文)

目的:研究顺铂与肾近端小管DNA的作用机制,和茵陈素的干预作用,方法:原代培养兔肾近端小管细胞(PTC).溴乙锭荧光测DNA链间交联,~(125)Ⅰ标记测DNA-蛋白交联,顺铂与PTC保温24h.茵陈素与PTC提前24 h保温后,加入顺铂26μmol·L~(-1)再保温24 h,结果:顺铂13到78 μmol·L~(-1)和26到78 μmol·L~(-1)可使PTC形成DNA链间交联和DNA-蛋白交联,茵陈素(0.4,4,8 mg·L~(-1))和(4,8 mg·L~(-1))组,DNA链间交联和DNA-蛋白交联分别低于顺铂(26μmol·L~(-1)),结论:顺铂导致肾近端小管形成DNA链间交联和DNA-蛋白交联,茵陈素减弱这两种作用。     

高糖环境下脂联素对人肾小管上皮细胞增殖和Caspase-3的影响

目的探讨脂联素（Adiponectin,ADPN）对高糖环境下人近曲肾小管上皮细胞增殖、凋亡及T-钙黏蛋白（T-cadherin）表达的影响,揭示脂联素在糖尿病肾病中的保护作用。方法将人近曲肾小管上皮细胞用5.5mmol/L葡萄糖（正常对照组）、30.0mmol/L葡萄糖（高糖组）、30.0mmol/L＋2.5μg/ml ADPN（脂联素组）分别培养24h,48h,72h后,运用MTT法测定细胞增殖,运用酶联免疫吸附法（ELISA）测定细胞上清液中Caspase-3的含量,观察细胞凋亡。结果①高糖组人近曲肾小管上皮细胞增殖被抑制（P〈0.05）,加入脂联素（2.5μg/ml）后促进了细胞增殖（P〈0.05）,并呈时间依赖性。②高糖组人近曲肾小管上皮细胞凋亡增加（P〈0.05）,加入脂联素（2.5μg/ml）后延缓了细胞凋亡。结论高糖环境下随着时间的延长,可引起肾小管上皮细胞增生肥大,诱导其凋亡;脂联素可促进细胞增殖,延缓细胞凋亡。     

Efficacy of gut lavage,hemodialysis, and hemoperfusion in the therapy of paraquat or diquat intoxication

Clinical and in vitro investigations were carried out to test the efficacy of gut lavage, hemodialysis, and hemoperfusion in the treatment of poisoning with paraquat or diquat. In a patient suffering from diquat intoxication 130 times more diquat was removed by gut lavage 30 h after ingestion than was removed by complete aspiration of the gastric contents.Determination of in vitro clearances for paraquat and diquat by hemodialysis showed that, at serum concentrations of 1–2 ppm, such as are frequently encountered in poisoning in man, toxicologically relevant quantities of herbicide cannot be removed from the body. At a concentration of 20 ppm, on the other hand, hemodialysis proved to be effective, the clearance being 70 ml/min at a blood flow rate of 100 ml/min. The efficacy of hemoperfusion with coated activated charcoal was on the whole better. Especially at concentrations around 1–2 ppm, the clearance values for hemoperfusion were some 5–7 times higher than those for hemodialysis.In a patient suffering from paraquat poisoning, both hemodialysis as well as hemoperfusion were carried out. The in vitro results could be confirmed: At serum concentrations of paraquat less than 1 ppm no clearance could be obtained by hemodialysis while by hemoperfusion with activated charcoal quite high clearance values were measured and the serum level dropped down to zero.

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Zusammenfassung Klinische Untersuchungen und Laboratoriumsversuche wurden durchgeführt, um die Wirksamkeit von Darmspülung, Hämodialyse und Hämoperfusion bei Paraquat- und Deiquat-Vergiftungen zu prüfen.Bei einem Patienten wurde 30 Std nach Deiquat-Aufnahme durch Darmspülung 130mal mehr Deiquat entfernt als durch vollständige Aspiration des Mageninhaltes. In vitro-Versuche ergaben, daß bei Blutserumkonzentrationen von 1–2 ppm, die bei Vergiftungen oft gemessen werden, durch Hämodialyse keine toxikologisch relevanten Paraquat- oder Deiquat-Mengen entfernt werden können. Dagegen erwies sich die Hämodialyse bei 20 ppm und einer Blutumlaufgeschwindigkeit von 100 ml/min mit einer Clearance von 70 ml/min als wirksam. Die Hämoperfusion mit beschicheter Aktivkohle war in diesen Versuchen aber eindeutig überlegen, denn insbesondere bei Konzentrationen um 1–2 ppm waren die Clearance-Werte 5–7mal höher als bei der Hämodialyse.Die in vitro-Ergebnisse wurden bei einem Patienten mit einer Paraquat-Vergiftung bestätigt: Bei Konzentrationen unter 1 ppm war die Hämodialyse wirkungslos, während durch Hämoperfusion relativ hohe Clearance-Werte erreicht wurden, so daß der Serumspiegel rasch unter die Nachweisgrenze abfiel.

     

In vitro studies on sterically stabilized liposomes (SL) as enzyme carriers in organophosphorus (OP) antagonism

This study describes a new approach for organophosphorous (OP) antidotal treatment by encapsulating an OP hydrolyzing enzyme, OPA anhydrolase (OPAA), within sterically stabilized liposomes. The recombinant OPAA enzyme was derived from Alteromonas strain JD6. It has broad substrate specificity to a wide range of OP compounds: DFP and the nerve agents, soman and sarin. Liposomes encapsulating OPAA (SL)* were made by mechanical dispersion method. Hydrolysis of DFP by (SL)* was measured by following an increase of fluoride ion concentration using a fluoride ion selective electrode. OPAA entrapped in the carrier liposomes rapidly hydrolyze DFP, with the rate of DFP hydrolysis directly proportional to the amount of (SL)* added to the solution. Liposomal carriers containing no enzyme did not hydrolyze DFP. The reaction was linear and the rate of hydrolysis was first order in the substrate. This enzyme carrier system serves as a biodegradable protective environment for the recombinant OP-metabolizing enzyme, OPAA, resulting in prolongation of enzymatic concentration in the body. These studies suggest that the protection of OP intoxication can be strikingly enhanced by adding OPAA encapsulated within (SL)* to pralidoxime and atropine.     

Aquatic Insects and Trace Metals: Bioavailability,Bioaccumulation, and Toxicity

Abstract

The uptake of metals from food and water sources by insects is thought to be additive. For a given metal, the proportions taken up from water and food will depend both on the bioavailable concentration of the metal associated with each source and the mechanism and rate by which the metal enters the insect. Attempts to correlate insect trace metal concentrations with the trophic level of insects should be made with a knowledge of the feeding relationships of the individual taxa concerned. Pathways for the uptake of essential metals, such as copper and zinc, exist at the cellular level, and other nonessential metals, such as cadmium, also appear to enter via these routes. Within cells, trace metals can be bound to proteins or stored in granules. The internal distribution of metals among body tissues is very heterogeneous, and distribution patterns tend to be both metal and taxon specific. Trace metals associated with insects can be both bound on the surface of their chitinous exoskeleton and incorporated into body tissues. The quantities of trace meals accumulated by an individual reflect the net balance between the rate of metal influx from both dissolved and particulate sources and the rate of metal efflux from the organism. The toxicity of metals has been demonstrated at all levels of biological organization: cell, tissue, individual, population, and community. Much of the literature pertaining to the toxic effects of metals on aquatic insects is based on laboratory observations and, as such, it is difficult to extrapolate the data to insects in nature. The few experimental studies in nature suggest that trace metal contaminants can affect both the distribution and the abundance of aquatic insects. Insects have a largely unexploited potential as biomonitors of metal contamination in nature. A better understanding of the physico-chemical and biological mechanisms mediating trace metal bioavailability and exchange will facilitate the development of general predictive models relating trace metal concentrations in insects to those in their environment. Such models will facilitate the use of insects as contaminant biomonitors.     

Pharmacological treatment of COVID-19: an opinion paper

The precocity and efficacy of the vaccines developed so far against COVID-19 has been the most significant and saving advance against the pandemic. The development of vaccines has not prevented, during the whole period of the pandemic, the constant search for therapeutic medicines, both among existing drugs with different indications and in the development of new drugs. The Scientific Committee of the COVID-19 of the Illustrious College of Physicians of Madrid wanted to offer an early, simplified and critical approach to these new drugs, to new developments in immunotherapy and to what has been learned from the immune response modulators already known and which have proven effective against the virus, in order to help understand the current situation.     

Alzheimer’s disease – current trends in basic and clinical research. Highlights from the 16th ECNP

Advances in the molecular biological knowledge of neuronal nicotinic acetylcholine receptors (nAChRs) have led to a growing interest by the pharmaceutical industry in the development of novel compounds that selectively modulate nAChR function. The ability of (-)-nicotine, an activator of nAChRs, to enhance attentional aspects of cognition in animals and humans, to exert neuroprotective and anxiolytic-like effects, and presumably to mediate the negative correlation between smoking and Alzheimer's (and Parkinson's) Disease, has focused interest on the potential therapeutic utility of modulators of nAChR function for treatment of some of the deficits associated with these progressive, neurodegenerative conditions. Numerous compounds are known which activate nAChRs and which might serve as lead compounds toward the development of such agents. The pharmacologic diversity of neuronal nAChR subtypes suggests the possibility of developing selective compounds which would have more favourable side-effect profiles than existing agents. This broader class of agents, collectively called cholinergic channel modulators (ChCMs), is anticipated to encompass compounds which would have more favourable side-effect profiles than existing agents, which generally exhibit low selectivity. This selectivity may be achieved by preferentially activating some subtypes of nAChRs (i.e., Cholinergic Channel Activators, ChCAs) or inhibiting the function of other subtypes (Cholinergic Channel Inhibitors, ChCIs). An overview of the biology of nAChRs and the rationale for the use of ChCMs for the treatment of dementia related to neurodegenerative diseases are presented, followed by a discussion of lead compounds and compounds under consideration for clinical evaluation.     

Steroidal sapogenin contents in some domestic plants

In order to find out the values of the steroid resources for the future use. the compositions and contents of steroidal sapogenins from 13 domestic plants have been investigated. As a result,Dioscorea nipponica, D. quinqueloba andSmilax china were found to have large amount of diosgenin. And pennogenin inTrillium kamtschaticum andParis verticillata, yuccagenin inAllium fistulosum, hecogenin inAgave americana and neochlorogenin inSolanum nigum were appeared to be major steroidal sapogenins.