鼠尾胶原在心肌细胞氧化损伤中的保护作用

背景:胶原蛋白具有抗氧化作用,但既往在实验室主要将鼠尾胶原用于促进细胞贴壁和支架构建,对于其抗氧化作用目前尚无相关研究。目的:探讨鼠尾胶原对过氧化氢导致离体心肌细胞氧化损伤的保护作用。方法:将原代培养的SD大鼠乳鼠心肌细胞随机接种到铺有鼠尾胶原的培养皿(实验组)和普通培养皿(对照组)中,并且均用0,10,100μmol/L H2O2诱导。24 h后,以电子显微镜观察各组乳鼠心肌细胞的形态,应用MTT比色法检测心肌细胞存活率,TUNEL法检测心肌细胞凋亡形态,流式细胞技术检测心肌细胞凋亡率,黄嘌呤氧化酶法检测超氧化物歧化酶活力,硫代巴比妥比色法检测丙二醛水平,Western-Blot检测凋亡蛋白Bax、Bcl-2的表达。结果与结论:两组培养皿中,随着过氧化氢浓度的增高,均可见细胞凋亡状态明显加重,细胞存活率及细胞内过氧化氢活力明显下降,细胞凋亡率及细胞内丙二醛水平明显增高,Bcl-2/Bax比值显著降低,呈剂量依赖性。而在相同浓度过氧化氢诱导下,与对照组相比,实验组细胞凋亡状态明显减弱,细胞存活率、超氧化物歧化酶活力及Bcl-2/Bax比值增高,细胞凋亡率和丙二醛水平明显减低。表明鼠尾胶原对过氧化氢所致的心肌细胞氧化损伤具有保护作用,其机制可能与提高超氧化物歧化酶活力,减少丙二醛产生及提高Bcl-2的表达有关。     

硫化氢拮抗乳鼠心肌缺氧/复氧损伤机制初探

目的： 观察乳鼠心肌细胞内源性CSE/H2S通路的改变以及给予H2S供体对缺氧/复氧心肌细胞的影响,探讨该通路与心肌缺氧/复氧损伤的关系及作用机制。方法：出生48 h以内乳鼠心肌细胞原代培养,缺氧(2%O2、5%CO2)3 h/复氧(21%O2、5%CO2)2 h造成缺氧/复氧损伤,采用比色法检测培养液中乳酸脱氢酶(LDH)、心肌细胞丙二醛（MDA）及超氧化物歧化酶（SOD）; 采用RT-PCR 方法测定心肌细胞CSE mRNA表达。结果：与缺氧/复氧组相比,NaHS+IR组及IR+NaHS组心肌细胞存活率明显提高,培养液中LDH漏出量降低,心肌细胞中SOD产生增加,MDA生成减少,加入CSE的抑制剂PPG后各项观察指标无明显变化,同时RT-PCR结果显示IR损伤可以下调心肌细胞中CSE mRNA的表达。结论：缺氧前后加入NaHS可以明显减轻乳鼠心肌细胞缺氧/复氧损伤,此作用可能是通过降低自由基和保护细胞膜完整性完成的。     

卡维地洛对培养心肌细胞氧化损伤的保护作用

目的:探讨卡维地洛对培养心肌细胞氧化损伤的保护作用和机制。方法:H2O2作用于体外培养的新生SD大鼠心肌细胞,建立心肌细胞氧化损伤模型。用卡维地洛预处理后,镜下观察心肌细胞测定心肌细胞存活率(MTT比色法),丙二醛(MDA)、还原型谷胱甘肽(GSH)、氧化型谷胱甘肽(GSSG)等指标水平。结果:卡维地洛干预后提高心肌细胞氧化损伤的细胞存活率(P0.01),减少MDA、GSG生成以及提高GSH的生成(P0.01)。结论:卡维地洛通过抗氧化作用对心肌细胞氧化损伤起保护作用。     

IL-6预处理保护H2O2致心肌细胞损伤作用机制初探

目的初步探讨IL-6预处理对H2O2致心肌细胞氧化应激损伤的作用机制。方法采用心肌细胞原代培养方法,以H2O2刺激心肌细胞,建立细胞氧化应激模型;采用MTT法检测细胞活力;AnnexinV-FITC染色法和流式细胞术检测细胞凋亡率;检测心肌细胞内谷胱甘肽（GSH）、超氧化物歧化酶（SOD）、丙二醛（MDA）的表达情况。结果 H2O2可降低心肌细胞存活率并能增加其凋亡,IL-6预处理后能显著改善细胞活力及凋亡情况,与模型组相比差异有统计学意义（P〈0.05）。低浓度IL-6能明显增加细胞内GSH与SOD的水平,并降低MDA的含量,随着IL-6浓度的增加,这种效应逐渐消失。结论 IL-6预处理能保护H2O2致心肌细胞损伤作用,这可能与IL-6调节细胞GSH、SOD、MDA表达有关。     

BMF参与氧化应激致心肌细胞损伤的机制研究

<正>目的:观察Bcl-2-modifying factor(BMF)在氧化应激致心肌细胞损伤中的作用和机制。方法:在培养的乳鼠心肌细胞氧化应激模型上,采用LDH活性检测和TUNEL法观察细胞损伤,荧光染色技术观察线粒体分裂和BMF在细胞中定位,RT-PCR和Western blot方法观察BMF mRNA和蛋白表达。结果:正常生理状态下,BMF定位在胞浆的细胞骨架,当用过氧化氢处理心     

烧伤合并吸人性肺炎后心肌细胞膜ATP酶的变化

目的探讨烧伤或烧伤合并感染后心肌功能损害的原因.方法制作30%Ⅲ烧伤,吸人性肺炎的动物(大白鼠)模型.分成S组(假伤)、P组(单纯肺炎)、B组(烧伤)、BP组(烧伤+肺炎)等四组.测定四组实验动物心肌细胞膜上Na+-K+-ATPase,Mg++-ATPase,Ca++-ATPase,Ca++-Mg++-ATPase4种ATP酶的活力,同时作血培养.结果B组、P组、BP组心肌细胞膜ATP酶活力较N组明显下降.同时血培养阳性率也明显增高,以BP组最高.结论烧伤后易发生感染,由于烧伤感染后心肌细胞ATP酶活力下降,导致伤后心肌功能的下降及心脏的损害.     

吡格列酮与胰岛素对大鼠心肌缺血再灌注损伤的保护作用

目的:研究吡格列酮与胰岛素联合应用对缺血再灌注损伤心肌细胞的保护作用,探讨其作用机制.方法:取Wistar大鼠幼鼠心室肌细胞进行体外培养,建立缺血再灌注损伤细胞模型.应用台盼蓝排斥试验测定细胞存活率,比色法检测各组培养液中乳酸脱氢酶(LDH)、肌酸激酶(CK)、超氧化物歧化酶(SOD)和丙二醛(MDA)的含量,激光扫描共聚焦显微镜观察细胞内钙离子荧光强度,透射电镜观察心肌细胞超微结构.结果:吡格列酮与胰岛素联合应用町提高缺血再灌注损伤心肌细胞的存活率,降低细胞培养液中的LDH、CK和MDA含量,提高SOD的含量,降低心肌细胞钙离子染色的荧光强度.部分恢复心肌细胞的超微结构,与单独应用吡格列酮或胰岛素相比,具有统计学意义.结论:吡格列酮与胰岛素联合应用对心肌缺血再灌注损伤有更好的保护效果.     

白藜芦醇调控内质网应激对肥大心肌细胞的保护作用研究

<正>目的:探讨白藜芦醇(resveratrol,Res)对异丙肾上腺素(isoproterenol,ISO)诱导的大鼠肥大心肌细胞的保护作用及机制。方法:ISO建立乳鼠心肌肥大细胞模型,分为control组、ISO组、Res干预组和Res对照组。检测心肌细胞表面积和ANP基因表达;流式细胞仪检测细胞凋亡率;电镜观察心肌细胞超微结构;检测培养液中乳酸脱氢酶(LDH)和丙二醛(MDA)含量;RT-     

PKC和ERK在大鼠心肌缺氧预处理延迟保护机制中的作用

目的:探讨蛋白激酶C(PKC)和细胞外信号调节激酶(ERK)在大鼠缺氧预处理(APC)延迟保护机制中的作用及二者之间的相互关系。方法:建立培养乳鼠心肌细胞缺氧/复氧(A/R)损伤和APC延迟心肌保护模型,用PKC兴奋剂(PMA)模拟预处理延迟保护模型,分别应用PKC和ERK抑制剂干预模型,并在各组相当于预处理后10min取材检测ERK活性。以实验终点检测培养基中乳酸脱氢酶(LDH)活性、细胞存活率、心肌细胞超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量作为心肌细胞损伤的指标。结果:预处理组心肌细胞存活率和SOD含量均显著高于A/R组(P＜0.05),培养液内LDH漏出和心肌细胞内MDA含量显著低于A/R组(P＜0.05),ERK活性显著高于A/R组(P＜0.05),应用PMA激活PKC可以模拟预处理的保护作用;ERK阻滞剂PD98059消除了缺氧和PMA的预处理保护作用,并抑制了预处理后的ERK活性的升高;PKC抑制剂多粘菌素B对APC引起的ERK激活及延迟保护作用无明显影响,但可抑制PMA诱导的保护现象。结论:ERK活化可能是APC延迟保护机制中的必须信号转导途径;PKC活化可以通过激活ERK启动缺氧预处理的延迟保护机制。     

心肌肽素抗培养心肌细胞阿霉素损伤作用

目的:观察小分子多肽类物质心肌肽素抗培养心肌细胞阿霉素损伤作用。方法:建立培养心肌细胞阿霉素(ADM)损伤模型, 观察心肌肽素对心肌细胞肌酸磷酸激酶(CPK)、乳酸脱氢酶(LDH)及线粒体脱氢酶活性的影响, 以荧光染料Fura-2-AM定量测定细胞内游离Ca²⁺浓度。结果:心肌肽素可剂量依赖性降低细胞培养液中CPK和LDH活性及对抗细胞内线粒体脱氢酶活性下降, 可剂量依赖性地降低培养心肌细胞[Ca²⁺]_i。结论:心肌肽素对阿霉素损伤培养心肌细胞具有保护作用。     

Schizophrenia in a North Swedish geographical isolate, 1900–1977. Epidemiology, genetics and biochemistry

Over 200 schizophrenic patients belonging to three major and interrelated pedigree complexes have been investigated over the past 30 years in a North Swedish geographically isolated population, presently numbering about 6,000. An intensive investigation of a number of biochemical correlates and genetic markers in a few selected families belonging to one of the major pedigrees has indicated new strategies for the current research program.
Schizophrenia, as defined operationally, is significantly associated with decreased activities of two enzymes (1) blood platelet monoamine oxidase, (2) plasma dopamine-β-hydroxylase, and (3) with the genetic marker Gc² (group specific antigen). Both enzymes are subject to genetic variation. A positive score for linkage between schizophrenia and low plasma DBH activity has been calculated, but, so far, available data are insufficient for discrimination between linkage and partial contribution of genetically controlled low plasma DBH to the pathogenesis of the disease. Alternatively, both mechanisms could be involved.
As a model for continued research, schizophrenia is explained as based on a double dominant-recessive genotype (Aabb), representing a vulnerability which in about 50 % of cases develops into clinical schizophrenia. It is suggested that the dominant mutation (A) operates on or affects MAO activity, and that the recessive genotype (bb) is instrumental in low variates of DBH activity and very likely such variates within the normal range of physiological variation. Moreover, it is suggested that the combined effects of MAO- and DBH-reduced efficiency on the metabolism of e.g. dopamine could be an essential pathogenic mechanism for the schizophrenic illness which is segregating in this population.     

The dominant diseases of modernized societies as omega-3 essential fatty acid deficiency syndrome: Substrate beriberi

About 1900, modern food selection and processing caused widespread $\text{epidemics}$ of the B vitamin deficiency diseases of beriberi and pellagra which, for genetic reasons, often expressed as different diseases ranging from bowel and heart disease to dermatoses and psychoses. But the B vitamins merely help convert essential fatty acids (EFA) into the prostaglandin (PG) tissue regulators and it now turns out that, through hydrogenation, milling and selection of w3-poor southern foods, we have also been systematically depleting, by as much as 90%, a newly discovered trace Nordic EFA (w3) of special importance to primates and sole precursor of the PG3(4) series, even as a concurrent fiber deficiency increases body demand for EFA. Since substrate EFA is processed by many B vitamin catalysts, an EFA deficiency will mimic a $\text{panh}$ypovitaminosis B, i.e., a mixture of $\text{substrate}$ beriberi and $\text{substrate}$ pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse $\text{endemic}$ disease. This would consitute a second stage of the Modern Malnutrition and explain why some workers now hold the dominant diseases of modermized societies to be new, nutritionally based, pellagraform yet lipid-related and to range, once again, from heart disease to psychosis. It is an assumption that our dominant diseases are unrelated to each other or are merely revealed by our diagnostic acumen and therapeutic success; and that hydrogenating millions of tons of food oils annually, to destroy the rancidity producing w3-EFA, is safe for $\text{primates}$. Extensive beriberiform disease is reported here in 32 typical cases taken from medical practice which responds strikingly to linseed oil supplements (60% w3-EFA) in confirmation of identical results in Capuchins.     

The universal muscular chain reaction,muscle spasm,Torsions, ruptures and extravasations. Chameleons of pathology and some manifestations of simple muscular disorders

Most bodily functions require the coordinated actions of complementary and supplementary paired muscle groups. Where this essential muscular cooperation is lacking, hollow organs may burst and others become literally screwed up, giving rise to many similar spastic diseases such as Torticollis, Twisted ovarian cyst, Torsion of the Testis, Volvulus of the intestines, Varicose Veins, Megacolon, Aortamegaly, Scoliosis, Erb's Palsy, Peyronie's Disease, Main-en-Griffe, Undescended Foot (Pes Cavus), Talipes, Strabismus. Spasm is “panenepidemic” and unclassified examples of Torsion Dystonia and Dyskinesia really are as common as debt and taxes.     

'Very sore nights and days': the child's experience of illness in early modern England, c.1580-1720

Sick children were ubiquitous in early modern England, and yet they have received very little attention from historians. Taking the elusive perspective of the child, this article explores the physical, emotional, and spiritual experience of illness in England between approximately 1580 and 1720. What was it like being ill and suffering pain? How did the young respond emotionally to the anticipation of death? It is argued that children’s experiences were characterised by profound ambivalence: illness could be terrifying and distressing, but also a source of emotional and spiritual fulfilment and joy. This interpretation challenges the common assumption amongst medical historians that the experiences of early modern patients were utterly miserable. It also sheds light on children’s emotional feelings for their parents, a subject often overlooked in the historiography of childhood. The primary sources used in this article include diaries, autobiographies, letters, the biographies of pious children, printed possession cases, doctors’ casebooks, and theological treatises concerning the afterlife.     

Guidelines for the Validation and Use of Immunoassays for Determination of Introduced Proteins in Biotechnology Enhanced Crops and Derived Food Ingredients

Recent advancements in agricultural biotechnology have created a need for analytical techniques to determine introduced proteins in crops enhanced through modern biotechnology techniques. These proteins are expressed in plant tissues and may be present in food ingredients. Immunoassays are ideally suited for protein detection and may be used as both quantitative and threshold methods. Microplate ELISA and lateral flow devices are two of the most commonly used immunoassay formats for agricultural biotechnology applications. This paper provides general background information and a discussion of criteria for the validation and application of immunochemical methods to the analysis of proteins introduced into plants and food ingredients using biotechnology methods. It is the result of a collaborative effort of members of the Analytical Environmental Immunochemical Consortium. This collaborative effort represents the combined expertise of several organizations to reach consensus on establishing guidelines for the validation and use of immunoassays. Further, the paper offers developers and users a consistent approach to adopting the technology as well as aid in producing accurate and meaningful results.     

Ultracryotomy: development and application (with examples from the yeast cytology) (author's transl)

The preparation steps usually necessary for obtaining ultrathin frozen sections of biological material (chemical prefixation, enclosing, cryoprotective treatment, freezing, sectioning, and post-staining the sections for transmission electron microscopy) are submitted to a critical analysis. The application of cryo-ultramicrotomy, in particularly for cytochemical purposes, is reviewed. Fundamental considerations of chemical prefixation and poststaining are supported by examples from yeast cytology. Furthermore, the efficiency of the cryo-ultramicrotomy (electron optical resolution of ultrastructural details) is demonstrated on yeast cells and protoplasts.     

Hypo- und Hypermagnesämie aus kardiologischer Sicht

Zusammenfassung Eine Reihe pathologischer Zustände bedingen Magnesiummangel. Zustände mit Hypermagnesämie sind ebenfalls bekannt, doch wesentlich seltener. Für den Kardiologen beachtenswert ist, daß unter Therapie mit bestimmten Diuretica bei Herzinsuffizienz, bei Herzinfarkt, Kardiomyopathie, Digitalisintoxikation und bestimmten Herzrhythmusstörungen Hypomagnesämie beobachtet wurde. Leider kann in der klinischen Routine nur ein extracelluläres Magnesiumdefizit durch Serumbestimmungen gemessen werden; über Magnesiummangel einzelner Organe kann nichts ausgesagt werden. Hinweise für Magnesiummangel geben aber neben der Messung des Serumspiegels Anamnese, klinischer Befund, bestimmte EKG-Veränderungen wie auch evtl. Hypokalämie, ein Zustand, bei dem sich oft — besonders bei Aldosteronismus — parallele Veränderungen zeigten.Tierexperimente deuten darauf hin, daß infarktähnliche Läsionen unter Magnesiummangel entstehen, doch ob Herzinfarkt beim Menschen durch Magnesiummangel ausgelöst werden kann, ist noch ungeklärt. In Leichenherzen zeigte sich im Infarktgebiet neben Calciumakkumulation signifikanter Magnesiumverlust, wobei unklar blieb, ob sich Ursache oder Folge des Infarktes widerspiegelten. Falls ein ursächlicher Zusammenhang besteht, ist er im Myokardstoffwechsel selbst zu suchen, wie bei der Alkoholkardiomyopathie, wo myokardialer Magnesiummangel zumindest als pathogenetischer Teilfaktor anerkannt wird. Andererseits versucht man aber auch Beziehungen zwischen Atherosklerose, Blutgerinnung und Hypomagnesämie herzustellen, in der Meinung, daß Magnesiummangel auch über den coronaren Pathomechanismus des Herzinfarktes wirken könnte. Sicher scheint, daß gewisse EKG-Veränderungen und Herzrhythmusstörungen durch einen irritierten Magnesiumhaushalt bedingt sein können, da sie bei Gabe bzw. Entzug von Magnesium verschwinden. Daß Magnesiummangel die Glykosidtoleranz verringert, wird tierexperimentell bestätigt. Unter Hypomagnesämie bewirkt Acetylstrophanthidin eher und länger Rhythmusstörungen als ohne, außerdem lassen diese sich durch Magnesiumgaben eliminieren. Da in gewissen Fällen spontane und digitalisinduzierte Herzrythmusstörungen durch Magnesiuminjektionen beseitigt wurden, scheint Magnesium als Therapeuticum angebracht. Einsatz verschiedener Magnesiumsalze bei Angina pectoris, degenerativen Herzerkrankungen und Herzinsuffizienz ohne geprüften und offensichtlich gestörten Magnesiumhaushalt ist fragwürdig, weil keine eindeutigen klinischen Erfolgsbeweise vorliegen. Immerhin mag es aber larvierte, durch Serumbestimmungen nicht erfaßbare Mangelzustände geben. Allgemein erscheint es aus kardiologischer Sicht ratsam, den Magnesiumhaushalt zu überwachen und in entsprechenden Fällen auszugleichen, um möglichen Myokardläsionen oder fatalen Herzrhythmusstörungen entgegenzuwirken.     

HLA in North Colombia Chimila Amerindians

HLA-A,-B,-C,-DRB1 and -DQB1 alleles have been studied in Chimila Amerindians from Sabana de San Angel (North Colombian Coast) by using high resolution molecular typing. A frequent extended haplotype was found:HLA-A*24:02-B*51:10-C*15:02-BRB1*04:07-DQB1*03:02 (28.7%) which has also been described in Amerinndian Mayos Mexican population (Mexico, California Gulf, Pacific Ocean). Other haplotypes had already been found in Amerindians from Mexico (Pacific and Atlantic Coast), Peru (highlands and Amazon Basin), Bolivia and North USA. A geographic pattern according to HLA allele or haplotype frequencies is lacking in Amerindians, as already known. Also, five new extended haplotypes were found in Chimila Amerindians. Their HLA-A*24:02 high frequencies characteristic is shared with aboriginal populations of Taiwan; also, HLA-C*01:02 high frequencies are found in New Zealand Maoris, New Caledonians and Kimberly Aborigines from Australia. Finally, this study may show a model of evolutionary factors acting and rising one HLA allele frequency (-A*24:02), but not in others that belong to the same or different HLA loci.     

The case for allele‐specific recognition by the TCR

There is a sharp difference in how one views TCR structure–function–behaviour dependent on whether its recognition of major histocompatibility complex‐encoded restriction elements (R) is germline selected or somatically generated. The generally accepted or Standard model is built on the assumption that recognition of R is by the V regions of the αβ TCR, which is not driven by allele specificity, whereas the competing model posits that recognition of R is allele‐specific. The establishing of allele‐specific recognition of R by the TCR would rule out the Standard model and clear the road to a consideration of a competing construct, the Tritope model. Here, the case for allele‐specific recognition (germline selected) is detailed making it obvious that the Standard model is untenable.