Rab7在自噬体和溶酶体融合过程作用的研究进展

自噬体与溶酶体的有效融合是细胞发挥自噬功能对细胞内多余物质进行降解和再利用的关键。自噬体与溶酶体的融合受控于复杂的信号通路网络,涉及多个环节及众多分子的协同作用,并与内吞机制有部分重叠。Ras相关蛋白7(Rab7,小GTP酶家族的成员)可能是自噬体与溶酶体的融合进程中最为重要的分子之一,在指导自噬体成熟、胞内负荷运输及与溶酶体的对接与融合过程中发挥重要调节功能。自噬体与溶酶体的融合障碍可引起先天性及适应性免疫应答异常,导致炎症、肿瘤及胞内微生物感染的加重。因此控制Rab7的活性可能成为治疗这些疾病的潜在靶点。     

细胞自噬的形态学特征和功能意义

目的 自噬是细胞受到刺激后吞噬自身的细胞质或细胞器,最终将吞噬物在溶酶体内降解的过程.按吞噬物进入溶酶体的途径,自噬可分为巨自噬、微自噬和分子伴侣介导的自噬3类.在巨自噬,自噬前体包裹细胞质或细胞器后形成自噬体,继而自噬体与溶酶体结合形成自噬溶酶体,自噬体内容物被降解.在微自噬,溶酶体膜凹陷,直接吞噬细胞质、细胞器或细胞核,形成自噬体,然后被溶酶体酶降解.分子伴侣介导的自噬是通过溶酶体膜的受体将细胞质内的蛋白质转运入溶酶体.自噬从酵母至哺乳动物细胞均很保守,对于耐受饥饿和缺血,清除衰老细胞器,清除细菌和异物,维持细胞活性和延长寿命等起着重要作用.自噬活动受自噬基因的调控,自噬基因缺失或功能障碍时可导致某些疾病的发生.深入认识自噬过程以及由此产生的自噬体等结构及其功能有助于探讨自噬对于人体生理和病理作用的机制.本文综述了自噬的形态学特征及其功能意义.     

感染细胞内问号钩端螺旋体吞噬泡形成及其与溶酶体的融合

目的了解问号钩端螺旋体（简称钩体）感染宿主细胞后吞噬泡形成、吞噬泡与溶酶体融合及感染细胞超微结构改变。方法用问号钩体黄疸出血群赖型56601株感染小鼠单核巨噬样细胞j774A．1和猴肾成纤维细胞Cos-7。采用透射电镜观察J774A．1细胞和Cos-7细胞胞内钩体吞噬泡的形成及感染细胞超微结构的改变。采用免疫双荧光染色法和激光共聚焦显微镜，观察含钩体吞噬泡与溶酶体融合情况。结果问号钩体56601株感染J774A．1细胞30min、感染Cos-7细胞15min即可在胞浆中发现膜包绕的含钩体吞噬泡，吞噬泡内钩体均保持原有生理弯曲。56601株问号钩体感染Cos-7细胞2h后，钩体吞噬泡膜开始消失，但未发现j774A．1细胞内钩体吞噬泡膜消失的现象。J774A．1细胞内钩体吞噬泡与溶酶体发生共区域化，表明吞噬泡与溶酶体发生融合。J774A．1细胞感染钩体后出现染色质浓缩形成的凋亡小体样结构、细胞空泡变性、线粒体肿胀等超微结构病变，但Cos-7细胞感染钩体后其超微结构基本正常。结论问号钩体感染J774A．1细胞和Cos-7细胞后可迅速形成吞噬泡并可能与钩体Ⅲ型分泌系统产物有关。J774A．1细胞内钩体吞噬泡可与溶酶体发生融合。不同细胞的钩体吞噬泡膜消失及超微结构改变有明显差异。     

自噬及其在肿瘤中的作用研究

 自噬（autophagy）是由 Ashford 和 Porter 在 1962 年发现细胞内有“自己吃自己”的现象后提出的，是指从粗 面内质网的无核糖体附着区脱落的双层膜包裹部分胞质 和细胞内需降解的细胞器、蛋白质等成分形成自噬体（autophagosome），并与溶酶体融合形成自噬溶酶体，降解其所包裹的内容物，以实现细胞本身的代谢需要和某些细胞器的更新^[1]。自噬在机体的生理和病理过程中都能见到，其所起的作用是正面还是负面的尚未完全阐明，对肿瘤的研究尤其如此，值得关注。 1 自噬的功能与作用机制 自噬主要的生理功能是将胞质中的大分子物质（如 蛋白质、RNA、过量储存的糖原等）和一些细胞内源性底物（包括由于生理或病理原因引起的衰老、破损的细胞器）在单位膜包裹的囊泡中大量降解，实现再循环，以维持细胞自身的稳定。这个过程对于细胞成分更新、保持旺盛的生理状态是至关重要的^[2]。在此过程中，自噬体的形成是关键，其直径一般为 300 ~ 900 nm，平均 500 nm，囊泡内常见的包含物有胞质成分和某些细胞器如线粒体、内吞体、过氧化物酶体等。与其他细胞器相比，自噬体的半衰期很短，只有 8 min 左右，说明自噬是细胞对于环境变化的有效反应。根据细胞物质运到溶酶体内的途径不同，自噬分为以下几种。①大自噬：由内质网来源的膜包绕待降解物形成自噬体，然后与溶酶体融合并降解其内容物^[3]；②小自噬：溶酶体的膜直接包裹长寿命蛋白等，并在溶酶体内降解；③分子伴侣介导的自噬（CMA）：胞质内蛋白结合到分子伴侣后被转运到溶酶体腔中，然后被溶酶体酶消化。CMA 的底物是可溶的蛋白质分子，在清除蛋白质时有选择性，而前两者无明显的选择性^[4]。     

细胞自噬在神经胶质瘤治疗中的研究进展

<正>1 自噬概述"Autophagy"即自噬,这个词是de Duve等~([1])于1966年发现溶酶体的同时创造出来的,描述的是具有单层或双层膜的结构吞噬受损的蛋白质和细胞器等功能失调的细胞组分形成自噬体,之后与溶酶体融合形成自噬溶酶体,最后将包裹物降解的一个过程。通过自噬降解的包裹物包括糖、核苷酸、氨基酸和脂肪酸,最终自噬体会同溶酶体进行融合进而将细胞器降解,这一过程可以为细胞提供大量的营养物质以及用于细胞再生的结构基础。直到1992年T     

肉芽组织破纤维细胞溶酶体包裹相的电镜观察

本文对大白鼠新生肉芽组织内的破纤维细胞进行了超微结构和细胞化学的观察。电镜下可见破纤维细胞内含有大量的各级溶酶体,这些溶酶体的酸性磷酸酶反应均呈阳性。溶酶体不但能与异噬泡和自噬泡融合,还能主动吞噬细胞器和溶酶体等。溶酶体的主动吞噬有三种形式,即突起包裹、内陷包裹和混合包裹。突起包裹的膜由五层结构组成,即两层单位膜,两层亮层,及中央板。大溶酶沐还以出芽、纹窄的形式形成小溶酶体。溶酶体的这种活动可能与细胞吞噬机能的自我调节有关。本文还就破纤维细胞与巨噬细胞之间的关系进行讨论。     

自噬溶酶体抑制剂氯化铵促进维生素K3诱导人宫颈癌HeLa细胞凋亡的作用

 目的： 探讨自噬溶酶体抑制剂氯化铵（NH4Cl）在维生素K3（VK3）诱导的HeLa细胞凋亡过程中的作用。方法：实验分为4组：正常对照组、30 μmol/L VK3作用组、10 mmol/L  NH4Cl作用组和30 μmol/L VK3+10 mmol/L NH4Cl联合作用组。MTT 法检测细胞存活率;吖啶橙（AO）染色观察溶酶体膜通透性变化,单丹磺酰尸胺（MDC）染色观察自噬泡的变化,BCECF-AM染色流式细胞术检测细胞浆pH变化,Hoechst 33342染色检测细胞核染色质凝聚状态及细胞凋亡率。结果：与对照组相比,单独应用NH4Cl 对HeLa细胞无明显影响。VK3作用组HeLa细胞存活率降低,AO染色荧光没有变化,细胞内出现自噬泡,细胞浆呈酸性,细胞核染色质凝聚,细胞发生凋亡。NH4Cl 与VK3联合作用于HeLa细胞时,与单独应用VK3组相比,溶酶体通透性增加,细胞内自噬泡更加聚集,细胞浆酸性增强,细胞凋亡率明显增加。结论：自噬溶酶体抑制剂NH4Cl促进了VK3诱导的HeLa细胞凋亡,表明自噬可能在VK3诱导的HeLa细胞损伤过程中起到保护作用。     

自噬对适应性免疫的调控

自噬(autophagy)是一种蛋白降解系统,根据细胞内底物运送到溶酶体腔方式的不同,可分为大自噬(macroautophagy)、微自噬(microautophagy)、分子伴侣介导的自噬(chaperone-mediated autophagy,CMA)三种[1].大自噬中,孤立的双层膜结构包裹变性坏死的细胞器,聚集的蛋白质和病原体等成分,形成自噬体( autophagosome).然后与溶酶体膜融合,形成自噬溶酶体(autophagic lysosome),降解所包裹的物质.自噬在固有免疫和适应性免疫调控中发挥重要作用.就适应性免疫而言,自噬在抗原提呈中起着必不可少的作用[2].经典免疫学认为,MHC Ⅰ类分子把内源性抗原提呈给CD8+T细胞,而MHCⅡ类分子把外源性抗原提呈给CD4+T细胞.     

自噬对烧伤创面愈合的影响

细胞自噬是细胞在应激状态下应用溶酶体对自身损伤细胞器等物质进行分解,将产生的大分子物质予以回收利用,从而保留细胞活性的降解过程。自噬在细胞的发育和分化进程中起着至关重要的作用。烧伤创面经历炎症期、细胞增殖期和组织重塑期3个时期完成组织愈合。细胞自噬在烧伤创面愈合过程中,具有促进病原体清除,参与新生血管增殖、肉芽组织形成,改善上皮的角质化以及瘢痕重塑的作用。调控自噬,可影响烧伤创面愈合。本文综述细胞自噬在烧伤创面愈合中的研究进展。     

炎症性肠病的自噬与表观遗传修饰

文题释义：自噬：是一个吞噬自身细胞质蛋白或细胞器并使其包被进入囊泡,并与溶酶体融合形成自噬溶酶体,降解其所包裹的内容物的过程,以此实现细胞本身的代谢需要和某些细胞器的更新。 表观遗传：是指DNA序列不发生变化,但基因表达却发生了可遗传的改变,主要包括DNA甲基化、组蛋白修饰、染色质重塑以及非编码RNA的调控,这种改变在细胞发育和增殖过程中能稳定的传递。 背景：炎症性肠病是一种与肠道自身免疫相关的慢性炎症性疾病,自噬是促进免疫调节的细胞途径,相关基因的表达异常与肠道炎症以及免疫反应关系密切,而表观遗传修饰对炎症性肠病自噬的调控机制尚未阐明。 目的：文章旨在对表观遗传修饰在炎症性肠病自噬中的调控作用作一介绍,以期探讨炎症性肠病自噬的发生机制。 方法：检索PubMed数据库,检索时限1998年1月至2019年4月,检索关键词为“inflammatory bowel disease,autophagy,autophagy related genes,epigenetic modification,DNA methylation,histone modification,chromatin remodeling,miRNA”,选择61篇符合标准的文献。 结果与结论：表观遗传(DNA甲基化、组蛋白修饰、染色质重塑、非编码RNA)可通过修饰炎症性肠病的易感基因ATG、IRGM等来调控肠道炎症、免疫以及自噬,从而介导炎症性肠病的发生和发展。 ORCID: 0000-0003-0627-9236(郭娅静) 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程     

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.     

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.     

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.     

'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.     

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.     

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.     

The universal muscular chamber. A basic unit of the genitourinary, cardiovascular, gastro-intestinal, skeletal, cutaneous, respiratory and other systems, endocameral hypertension; and spasm, the key to their idiopathic diseases and arthropathies

Starting with the integument, we see many organs are contractile sacs or multiples thereof, which tubes or bags constitute the major part of the entire body. Recognition of this basic unit and its characteristics sheds new light, individually and collectively, on many disorders previously considered unrelated. Muscular tears and perforations develop in the walls of these chambers, being no way peculiar to those organs, wherein, hydrochloric acid occurs. So, it is not necessary to explain the absence of excessive acid from patients who exhibit holes in the gastric, uterine, aortic, duodenal, rectal, pulmonary, retina, and other walls. Muscle, not acid is the great common factor relating idiopathic disorders in the gastrointestinal tract to each other and to similar diseases in other systems. When the units are linked together, the lesions tend to appear as arthropathies, i.e. at the joints. Rephrasing common-place observations, frees us from conventional, conceptual cul-de-sacs. An observation is only as good as its interpretation, so all possibilities must be considered, otherwise, we will remain blinded by our misconceptions.     

Der Einfluß von Nahrungsmitteln und Rauchen auf die klinisch-chemische Diagnostik von Phäochromozytom,Neuroblastom und Karzinoid-Syndrom

Zusammenfassung Der Einfluß von verschiedenen Nahrungsmitteln auf Methoden zur Bestimmung von Adrenalin (AD), Noradrenalin (NA), Vanillinmandelsäure (VMS), Metanephrinen (MN), Homovanillinsäure (HVS) und 5-Hydroxyindolessigsäure (5-HIE) im 24 h-Harn zur Diagnose des Phäochromozytoms bzw. Karzinoid-Syndroms wurde untersucht. Die in die Untersuchung einbezogenen Nahrungsmittel waren: Tee, Kaffee, Mandeln, Ananas, Käse, Walnüsse, Vanillepudding, Bananen, Tomaten und Milchschokolade. Außerdem wurde der Einfluß des Zigarettenrauchens auf die Bestimmung von AD, NA, VMS und MN untersucht.Walnüsse führten zu einer starken Erhöhung der 5-HIE-Ausscheidung. Bananen erhöhten die Ausscheidung von AD, NA, VMS, MN und 5-HIE. Kaffee und Ananas bewirkten eine geringe Zunahme der MN-Werte. Rauchen von 20–30 Zigaretten/Tag beeinflußte keine der vier Variablen.Wenn die beschriebenen Methoden benutzt werden, sollte lediglich auf den Verzehr von Bananen und Walnüssen vor und während der Harnsammelperioden verzichtet werden, da die oberen Normgrenzen im Harn überschritten werden könnten. Ein Verzicht auf Kaffee und Ananas in normalen Mengen ist nicht erforderlich. Es besteht kein Anlaß, weiterhin die bisherigen umfangreichen Restriktionen der übrigen Nahrungsmittel beizubehalten.