自噬抑制剂促进缺氧诱导的大鼠乳鼠心肌细胞凋亡简

 目的 探讨抑制自噬后对大鼠乳鼠心肌细胞缺氧诱导的促凋亡蛋白Bim、caspase-3表达的影响及低氧诱导因子1（HIF-1）的调控作用。方法 体外培养1～3d 龄SD大鼠心肌细胞建立缺氧模型,检测缺氧0、2、4、8、14和24h时自噬情况,取自噬显著升高的时间点细胞作为单纯缺氧组（anoxia组）,缺氧前用10mmol/L3-甲基腺嘌呤（3MA）预处理心肌细胞1h作为缺氧+3-甲基腺嘌呤组（anoxia+3MA组）,设立正常对照组（control组）。倒置显微镜下观察各组心肌细胞的搏动频率和异常节律;全自动血液生化分析仪检测乳酸脱氢酶LDH的活性;Western blot检测各组中LC3-II/ I、Bim、caspase-3和HIF-1蛋白表达情况。结果 抑制自噬后心肌细胞搏动频率明显减弱并可见异常节律、LDH释放增加（P<0.05）,同时Bim和caspase-3表达明显升高（P<0.05）;缺氧+3MA组中HIF-1蛋白表达明显低于单纯缺氧组（P<0.05）。结论 自噬抑制剂抑制自噬后导致缺氧诱导的大鼠乳鼠心肌细胞凋亡增加,HIF-1正调控缺氧诱导的自噬抵抗凋亡发挥心肌保护作用。     

缺氧诱导因子-1在心肌保护中的作用

缺氧诱导因子-1 （hypoxia-inducible factor-1,HIF-1）是一种依赖于氧调控的转录因子,其在维持氧稳态方面发挥重要作用。缺氧时,缺氧诱导因子-1可以稳定地表达,从而调控一系列缺氧相关基因的表达,其诱导表达的基因与能量代谢、细胞生存与增殖、血管新生、红细胞生成、肿瘤生长以及肿瘤多药耐药等相关。许多心脏疾病都有不同程度的缺氧,机体可对其产生一定程度的代偿。HIF-1是在心肌缺氧中起代偿作用的重要因素,其机制可能涉及缺血缺氧时HIF-1能够促进血管内皮生长因子、诱导型一氧化氮合酶、血红素氧合酶-1、内皮素-1和心房钠尿肽等基因的表达,从而发挥心肌保护作用。     

缺氧诱导因子-1的研究与应用进展

缺氧诱导因子 1(HIF 1)是细胞在缺氧条件下产生的一个主要调控因子 ,近年来的研究发现 ,HIF 1与血管生成、炎症发生和脂肪形成过程密切相关 ,并对肿瘤、心血管疾病、炎症和肥胖症的治疗具有重要的指导意义     

NF—κB通过HIF-1α的转录调节连接先天免疫和缺氧反应

缺氧反应是一个由低氧引起的古老的应激反应，并且受缺氧诱导因子-1（HIF-1）的控制，HIF-1的α亚基在含氧量正常的情况下会迅速退化，但是当由缺氧引起的氧依赖性脯氨酰羟化酶（PHDs）抑制时，α亚基很稳定。HIF—1α能控制与能量代谢和血管发生有关的基因，其含量受翻译后调节。另一个古老的应激反应是先天免疫反应，受一些转录因子调节，其中NF—κB起了核心作用。     

缺氧预处理保护机制的研究进展

缺氧预处理可触发机体的内源性保护机制,使机体对严重缺氧或其它致死性应激产生防御和抵抗。缺氧预处理的保护作用与缺氧诱导因子及其调控基因、PI3-K/Akt促细胞生存信号转导通路、活性氧、ATP敏感钾离子通道、Bcl-2等多种蛋白和信号分子的作用密切相关。     

缺氧诱导因子脯氨酸羟化酶的调控与缺血缺氧性疾病

缺氧诱导因子脯氨酸羟化酶作为氧感受器，通过氧依赖性地催化缺氧诱导因子特定脯氨酸残基的羟基化反应，从而介导缺氧诱导因子的降解，在缺氧诱导因子转录活性的调控过程中具有重要作用。缺氧诱导因子在各种缺血缺氧性疾病的发生及发展过程中起重要作用，但直接抑制其转录活性十分困难，因此深入研究其特异性的脯氨酸羟化酶的活性调控可能为防治此类疾病提供新的策略。     

缺氧感受器与信号传递

研究认为血红素蛋白或NAD(P)H氧化酶复合物是缺氧感受器。从而引发一系列信号传递过程 ,包括cAMP ,Ca2 ,NO ,CO ,cGMP等信使分子的参与 ,最终激活缺氧诱导因子 1 (HIF 1 ) ,使机体产生缺氧反应。还有人认为线粒体参与了这一过程而且可能就是缺氧感受器。HIF 1α蛋白也可能是直接感受缺氧的感受器。复杂而多样的缺氧感受机制提示机体对缺氧的反应可能并不遵循单一的路径。     

缺氧诱导因子-1与细胞凋亡

缺氧诱导因子 1(HIF -1)是一种主要由缺氧诱导细胞产生的重要的转录因子。HIF- 1的表达水平与糖酵解、细胞周期阻滞、细胞生存与增殖、血管新生、血管舒缩、红细胞生成、肿瘤生长,转移以及肿瘤多药耐药等许多生命活动密切相关。HIF- 1通过调控凋亡相关基因的转录在促细胞凋亡和抗细胞凋亡中都发挥着重要的作用。     

基因的缺氧诱导性表达调控

细胞可以通过改变基因表达方式而对细胞内外各种环境刺激产生应答反应，以维持其稳态（horn。tasis）。越来越多的研究表明，缺氧可以上调某些基因的表达，其中包括红细胞生成素（EPO）、血管内皮生长因子（VEGF）、血小板衍生生长因子（PDGF）、糖酵解西、转录因子和某些原癌基因等”’。这种基因的缺氧诱导性表达调控是通过特异的反式作用因于与DNA上的氧调节性顺式作用元件相互作用而实现的。一、HIF－l的生成与转录调节作用缺氧诱导因子河（hypoXia－induciblefactor－l，HIF－l）“’是从缺氧培养的细胞核粗提液中提取的一种…     

沉默HIF-1α表达逆转缺氧诱导肝癌免疫抑制的实验研究

目的:探讨缺氧诱导因子-1(HIF-1α)表达在缺氧诱导肝癌免疫抑制中的作用,以期阐明缺氧致肝癌免疫抑 制的分子机制。方法:构建缺氧C57BL/6 小鼠移植瘤模型,缺氧探针HypoxyprobeTM-1 标记缺氧组织,免疫组化检测缺氧组织 HIF-1α表达,qPCR 检测缺氧组织肿瘤免疫因子表达;慢病毒构建稳定敲减HIF-1α的Hepa1鄄6 小鼠肝癌细胞株,并移植于 C57BL/6 小鼠,6 周后检测移植瘤瘤重,Western blot 检测移植瘤HIF鄄1琢表达,流式细胞仪检测移植瘤中肿瘤浸润免疫细胞 CD4+CD25+ Foxp3+调节性T 细胞表达,qPCR 检测缺氧组织肿瘤免疫因子表达。结果:C57BL/6 小鼠缺氧移植瘤模型构建成 功,缺氧组织HIF鄄1琢高表达,肿瘤抑制因子IFN-γ、IL-12b 和CXCL10 低表达,肿瘤促进因子IL-10、IL-1β和IL-17 高表达;敲减 HIF-1α明显抑制了移植瘤生长,降低了CD4+ CD25+ Foxp3+调节性T 细胞浸润,同时抑制了肿瘤促进因子IL-10、IL-1β和IL-17 表达,促进了肿瘤抑制因子IFN鄄酌、IL鄄12b 和CXCL10 表达。结论:缺氧可诱导肝癌组织HIF鄄1琢表达及免疫抑制,相反,沉默 HIF鄄1琢可抑制移植瘤生长并逆转肝癌免疫抑制,揭示了HIF-1α在缺氧致肝癌免疫抑制中的作用,可能为将来肝癌诊治提供 新思路。     

Renal dysplasia and asplenia in two sibs

A family is reported in which two sibs, one male and the other female, both died within 24 hours of birth with enlarged polycystic kidneys. Postmortem histology in the second child showed gross renal dysplasia. In both children the pancreas was enlarged, nodular and cystic but the liver appeared macroscopically normal. In the second child, histological examination confirmed pancreatic fibrosis with cystic dilation of ducts, but showed portal fibrosis with bile duct proliferation in the liver.
This combination of findings is very reminiscent of those in a girl and her brother reported by Ivemark et al. (1959). The children reported here also showed absence or hypoplasia of the spleen, cardiac anomalies and other features of the Ivemark syndrome (Ivemark 1955), a quite different, usually sporadic, congenital disorder. It is suggested that the children described here have a distinct lethal congenital disorder, probably inherited in an autosomal recessive manner.     

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.     

What will studies of Fulani individuals naturally exposed to malaria teach us about protective immunity to malaria?

There are an estimated over 200 million yearly cases of malaria worldwide. Despite concerted international effort to combat the disease, it still causes approximately half a million deaths every year, the majority of which are young children with Plasmodium falciparum infection in sub-Saharan Africa. Successes are largely attributed to malaria prevention strategies, such as insecticide-treated mosquito nets and indoor spraying, as well as improved access to existing treatments. One important hurdle to new approaches for the treatment and prevention of malaria is our limited understanding of the biology of Plasmodium infection and its complex interaction with the immune system of its human host. Therefore, the elimination of malaria in Africa not only relies on existing tools to reduce malaria burden, but also requires fundamental research to develop innovative approaches. Here, we summarize our discoveries from investigations of ethnic groups of West Africa who have different susceptibility to malaria.     

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.     

Class II HLA in Georgia Caucasus Tbilisi Georgians and their Mediterranean ancestry: The Usko Mediterranean languages

Georgia (or Sakartvelo in its own language) is a South Caucasus Mts. country with its easternmost part is enigmatically named Iberia, like the Iberian Peninsula, which may refer to rivers “Kura” and “Ebro” or their valleys respectively. Most of their inhabitants speak Georgian which is included within Dene-Caucasian group and Usko-Mediterranean subgroup of languages. The latter includes Basque, Berber, ancient Iberian-Tartessian, Etruscan, Hittite, Minoan Lineal A and others. In the present paper, HLA class II -DRB1 and -DQB1 alleles has been studied and extended haplotypes calculated. Most frequent haplotypes are also of Mediterranean origin (i. e.: (A*02-B*51)-DRB1*11:01-DQB1*03:01, (A*02-B*51)-DRB1*13:01-DQB1*06:03, or (A*24-B*35)-DRB1*01:01-DQB1*05:01) and DA genetic distances show that closest world populations to Georgians are Mediterraneans. Georgians also show common extended haplotypes ((A*02-B*51)-DRB1*11:01-DQB1*03:01, (A*02-B*13)-DRB1*07:01-DQB1*02:01 and (A*03-B*35)-DRB1*11:01-DQB1*03:01) with Svan people, a secluded population in North Georgia mountains. We can conclude that Georgians belong to a very old Mediterranean substratum according to both linguistics (Usko Mediterranean languages) and HLA genetics.     

'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.