人支气管上皮细胞GCLC基因调控区ARE及E-box顺式调控元件调控功能的研究

目的通过对人γ-谷氨酰半胱氨酸酶催化亚单位(GCLC)基因调控区的ARE及E-box顺式调控元件诱导缺失突变,研究它们在人支气管上皮细胞内对GCLC基因转录调控功能的影响。方法应用PCR方法克隆人GCLC基因调控区的大部分核苷酸序列,构建表达虫荧光素酶报告基因的野生型质粒PL45。采用PCR重叠延伸产生特异位点诱变的方法对ARE及E-box顺式调控元件进行缺失突变,构建相应的突变型质粒PLdel-ARE及PLdel-E-box。通过瞬时基因转染方法将上述质粒转染人支气管上皮细胞系16HBE,观察基因突变后的基因转录调控功能。结果质粒PL45的虫荧光素酶相对活性值为9949.75±1441.33、质粒PLdel-ARE的虫荧光素酶相对活性值为21258.75±1563.64、质粒PLdel-E-box的虫荧光素酶相对活性值为17082.00±89.51。与野生型质粒PL45相比,PLdel-ARE、PLdel-E-box突变型质粒表达的虫荧光酶相对活性值显著上升。结论ARE及E-box顺式调控元件具有负性调控作用。     

人支气管上皮细胞GCLC基因调控区ARE及E-box顺式调控元件调控功能的研究

目的 通过对人γ-谷氨酰半胱氨酸酶催化亚单位(GCLC)基因调控区的ARE及E-box顺式调控元件诱导缺失突变,研究它们在人支气管上皮细胞内对GCLC基因转录调控功能的影响.方法 应用PCR方法克隆人GCLC基因调控区的大部分核苷酸序列,构建表达虫荧光素酶报告基因的野生型质粒PL45.采用PCR重叠延伸产生特异位点诱变的方法对ARE及E-box顺式调控元件进行缺失突变,构建相应的突变型质粒PLdel-ARE及PLdel- E-box.通过瞬时基因转染方法将上述质粒转染人支气管上皮细胞系16HBE,观察基因突变后的基因转录调控功能.结果 质粒PL45的虫荧光素酶相对活性值为9949.75±1441.33、质粒PLdel-ARE的虫荧光素酶相对活性值为21258.75±1563.64、质粒PLdel-E-box的虫荧光素酶相对活性值为17082.00±89.51.与野生型质粒PL45相比,PLdel-ARE、PLdel-E-box突变型质粒表达的虫荧光酶相对活性值显著上升.结论 ARE及E-box顺式调控元件具有负性调控作用.     

从噬菌体抗体库筛选人源性抗白细胞介素8抗体

目的: 从噬菌体抗体库中筛选人源性抗IL- 8单链抗体(scFV)。方法: 采用原核表达载体pRSET- IL- 8在大肠杆菌BL21(DE3)中表达IL- 8 His融合蛋白, 并通过亲和层析纯化。以该融合蛋白为固相抗原, 对噬菌体抗体库进行 3轮淘筛, 并对所获阳性克隆进行抗原结合活性测定和DNA序列测定。结果: 获得 2株特异性抗IL- 8噬菌体抗体。对其DNA序列测定结果表明, 其VH基因均属于人IgGVH3亚群, Vλ基因分别属于人VλDPL5和VλDPL2亚群。结论: 利用噬菌体抗体库技术可不经免疫制备人源性抗IL- 8抗体, 为银屑病及相关疾病的临床应用提供了条件。     

噬菌体Φ297切除酶(xis)基因的克隆和序列分析

肠道出血性埃希大肠杆菌可产生一种或多种志贺样毒素。这些毒素是由λ家族的溶原性噬菌体编码的,这些噬菌体DNA可重组整合到埃希菌大肠杆菌染色体DNA上,又可以通过切除酶从大肠杆菌染色体DNA上切离,而形成完整的噬菌体。λ家族噬菌体含有相同的基因图谱,功能相同的基因位于噬菌体染色体的相似位置。我们假设噬菌体Φ297也是一种λ噬菌体,并与其它的λ噬菌体含有相似的基因结构。因此,我们的研究是从本实验室已经测序的噬菌体Φ297的含40个核苷酸序列开始的,这段序列几乎与噬菌体933W的int基因是相同的,根据这一序列设计了接头引物和右边…     

DMD基因转录与逆转录PCR研究的历史与现状

由79个外显子与78个内含子构成的DMD基因在基因组DNA上跨越2400kb,其中98％的内含子DNA序列大部分尚属未知,导致在基因组水平上全面系统地研究DMD基因的结构及其突变存在重重无法克服的困难。而79个外显子构成的mRNA只有14kb,对其加以详细的研究则成为可能。正是由于对DMD基因转录子及其逆转录子(mRNA与cDNA)的研究,我们才知:(1)正常DMD基因跨越2400kb,拥有3个启动子,转录子的拼剪类型存在组织特异性及发育阶段特异性以及大量的外显子与内含子界限的确定;(2)突变DMD基因编码大量异常的剪接子,这些剪接子往往涉及一个或邻近的几个外显子的缺失或重复。同时出现了单一碱基置换或缺失的转录子,导致同义突变、错义突变、终止密码突变及移码突变的发生。本文就DMD基因转录及逆转录PCR研究的历史与现状加以综述。     

大肠杆菌脂多糖2630模拟位的研究

目的 :利用纯化的抗大肠杆菌L2 6 30多抗筛选噬菌体环七肽库 ,以获得可模拟脂多糖 (LPS)表位的短肽克隆。方法 :以亲和层析纯化的抗大肠杆菌L2 6 30多克隆抗体为靶分子 ,筛选噬菌体随机环七肽库 ,用双夹心ELISA和竞争抑制ELISA鉴定阳性噬菌体克隆的抗原性。结果 :对噬菌体环肽库进行 3轮筛选后 ,随机挑选 2 0个克隆 ,经鉴定其中 12个可与抗L2 6 30抗体结合 ,即为阳性克隆 ;其中有 5个阳性噬菌体克隆表现出与抗鼠伤寒沙门氏菌LPS多抗结合的活性 ,提示这 5个噬菌体展示的短肽具有模拟大肠杆菌LPS及鼠伤寒沙门氏菌LPS共同表位的性质。经DNA序列分析显示 ,其中 8个克隆的氨基酸序列具有X DGLL XX或X EDGLL X保守序列 ,其余 4个克隆的序列均不相同。结论 :筛选获得的噬菌体环七肽克隆具有模拟大肠杆菌LPS表位的活性 ,为大肠杆菌L2 6 30多表位模拟短肽。其中 5个阳性噬菌体克隆短肽具有模拟大肠杆菌LPS及鼠伤寒沙门氏菌LPS共同表位的活性     

哺乳动物精子发生中转录调控机制的特点

在哺乳动物精子发生中,存在着特异而精细的转录调控。生精细胞中活跃的转录活动,终止于圆形精子细胞向长型转变的过程之初。睾丸特异性转录调控包括:转录装置的过度表达、睾丸特异性转录因子及启动子的利用,特异性的转录调控途径。转录后调控的作用也十分重要。这些分子事件与卵子发生中的转录调控互有异同。     

完全型雄激素不敏感综合征雄激素受体基因突变的鉴定与分析

目的 对l例完全型雄激素不敏感综合征(complete androgen insensitivity syndrome,CAIS)患者的雄激素受体(androgen receptor,AR)基因进行分析,寻找潜在的突变位点,并进一步分析其发病原因.方法 提取患者外周血全基因组DNA,扩增位于X染色体AR基因8个外显子及邻近外显子与内含子剪切位点DNA序列,对扩增产物直接进行DNA序列测定,与GenBank中的基因序列进行比对.结果 该患者AR基因在第6外显子核苷酸序列3507位点缺失一个碱基C而引起移码突变,致使在第808位密码子出现终止密码子(TGA)使得翻译提前终止形成截短的雄激素受体蛋白.该突变可能诱导雄激素受体结合能力发生功能上的变异,导致CAIS的发生.结论 AR基因第6外显子核苷酸序列3507位点缺失碱基C引起的移码突变是一种导致CAIS新的基因突变方式,该研究丰富了AR基因突变谱,为了解CAIS的发病机制提供了新的依据.     

Dravet综合征患者SCN1A基因启动子区突变位点的检测及分析

目的 对Dravet综合征患者SCN1A基因启动子区突变位点的筛查及分析，预测其致病易感性。方法 收集24例Dravet综合征患者及100例正常人的外周血，抽提基因组DNA，PCR扩增SCN1A基因启动子区序列并测序；用生物信息学方法分析了SCN1A启动子区变异位点邻近序列的保守性及潜在的结合元件，推测其致病易感性。结果 从患者中发现两个突变位点-244 C>T和-662 G>-，都来自父亲，而没有血亲关系的正常人没有发现；-244和-662突变位点在哺乳动物中高度保守（100%）；人与其他哺乳动物之间-244突变位点邻近序列(位点上、下游20个碱基)的平均同源率高达90%，而-662突变位点邻近序列的平均同源率只有60%；含-244位点的序列分别能预测到4种不同的转录因子结合元件，而含-662位点的序列均未能预测到。结论 这两个突变与疾病存在一定程度的相关性，其致病的机理有待于实验证实。     

单核细胞增生李斯特菌毒力基因aroA启动子上阻碍PrfA转录调控元件的研究

目的 研究食源性致病菌单核细胞增生李斯特菌(Listeria monocytogenes,简称LM)毒力基因启动子的结构特点及其与转录调控因子PrfA(positive regulatory factor A)蛋白之间的关系.方法 选取plcA和aroA两个毒力基因启动子作为研究对象,plcA基因启动子(PplcA)上含有一个高度保守的PrfA蛋白结合序列TYAACAAATGTFAA(PrfA-box)和-10区(TAAGAT),其转录表达受PrfA强调控;aroA基因不受PrfA调控,所利用的启动子ParoA1为非依赖于PrfA的肩动子,但是在紧邻ParoA1的下游区域却含有一个与PplcA相似的PrfA-box(TTAAAACATGTTAA)和一个-10区(TTTAAT),该区域疑似为依赖于PrfA的启动子,被命名为ParoA2.应用PCR定点突变和SOEing PCR(重叠区扩增基因拼接法)技术互换了PplcA和ParoA2上可能影响PrfA蛋白结合以及诱发转录起始相关的碱基序列,构建了一系列PplcA-ParoA2杂合突变启动子,并插入到无启动子的lacZ报告基因上游,使lacZ基因的表达置于突变启动子下.获得的启动子融合表达质粒分别电转化入LM野生株P14、PrfA蛋白高表达突变株Pl4a和prfa基因等位缺失突变株A42中,检测相应的β-半乳糖苷酶活性以确定杂合突变启动子是否具有依赖PrfA的转录活性及其水平高低.结果 当肩动子上影响PrfA转录调控的两个核心元件PrfA-box与-10区的距离保持在最适的22或23个碱基时,交换PplcA和ParoA2上的两个相应核心元件的碱基序列并不改变启动子的转录活性.但是,当PplcA上的两个核心元件之间的碱基以及-10区下游的序列被相应ParoA2上的序列所替代后,PplcA依赖于PrfA的转录活性完全丧失,反之,ParoA2上的这两段序列如果被PplcA的序列所替换,ParoA2则表现出依赖于PrfA的转录活性.结论 ParoA2的-10区及其下游的序列可能形成发夹结构,阻碍RNA聚合酶-PrfA蛋白复合物结合到解旋的单链模板DNA上生成具有转录起始活性的开放复合物,从而抑制了ParoA2依赖于PrfA的转录活性的表达.     

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.     

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.     

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.     

'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.