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1.
目的 获得高纯度和高活性的B淋巴细胞刺激因子。方法 重组原核表达载体pQE-80L-BLyS112-285在大肠杆菌DH5a中经IPTG诱导表达rhBLyS112-285,超声碎菌,提取包涵体,经Ni^2 -NTA亲和层析和Sepharcryl S-200凝胶过滤层析纯化后,选择不同氧化还原条件进行复性,进而检测其生物学活性。结果 得到了有较高纯度和较好生物学活性的rhBLyS112-285蛋白。结论 优化了BLyS蛋白的纯化和复性的参数,所获结果为进一步研究创造了条件。  相似文献   

2.
重组人BAFF112-285的制备及活性分析   总被引:1,自引:3,他引:1  
目的 制备具有功能活性的重组人TNF家族的B细胞激活因子(B cell activating factor belonging to the TNF family,BAFF)胞外区112—285氨基酸残基段(rhBAFF112—285),为BAFF的深人研究奠定基础。方法 提取人HL-60细胞总RNA,经RT—PCR扩增编码人BAFF胞外区112—285氨基酸残基(BAFF112—285)的cDNA,行序列测定后,构建于原核表达载体pQE—80L并转化大肠杆菌DH5α,经IPTG诱导表达rhBAFF112—285,Ni^2 —NTA层析纯化,进而经^3H—TdR掺人实验检测其免疫学活性。结果 RT—PC双扩增得到了525bp的DNA片段,序列分析与GenBank中报道的编码人BAFF112—285的cDNA序列一致,该胞外区片段在大肠杆菌中获得了高效表达,表达水平达细菌总蛋白的45.7%,经纯化后纯度可达98.4%,活性检测证实其能明显刺激外周血淋巴细胞活化。结论 利用大肠杆菌可高效表达rhBAFF112—285,所获纯化产物具有生物学活性,所获结果为进一步研究创造了条件。  相似文献   

3.
目的: 研究人胶原沉积抑制因子(decorin)在大肠杆菌DH5α中的表达特性。方法: 用SDS-PAGE法检测pGEX-4T-1-decorin融合克隆在大肠杆菌DH5α中表达,选择阳性表达克隆;测定1 mmol/L异丙基-β-D-硫代半乳糖苷(IPTG)最佳诱导时间;用超声波裂解法分析GST-decorin融合蛋白的可溶性。用Western blotting进行定性分析。结果: 用1mmol/L IPTG诱导时,融合蛋白可在大肠杆菌DH5α中表达;最佳诱导时间为4h;大部分融合蛋白以包涵体的形式存在;所表达蛋白为GST融合蛋白。结论: GST-decorin融合蛋白可在大肠杆菌DH5α中大量表达,但以包涵体的形式存在。  相似文献   

4.
本研究旨在通过优化人β2微球蛋白在大肠杆菌中的表达条件并对重组蛋白进行纯化,以期获得可溶性好、纯度高的重组人β2微球蛋白(rhβ2M)。通过检测诱导剂IPTG浓度、诱导温度和诱导时间对rhβ2M可溶性表达的影响,确定最佳的诱导条件为IPTG终浓度0.8mmol/L,诱导温度25℃,诱导时间6h。在最佳诱导条件下进行发酵培养,获得可溶性rhβ2M占菌体总可溶蛋白含量的63.7%。对可溶性蛋白进行Ni Sepharose 6Fast Flow亲和层析纯化,可获得纯度达95%以上的rhβ2M。Western blot分析表明,该蛋白具有与抗人β2M抗体特异反应的抗原特性。  相似文献   

5.
目的:构建肿瘤坏死因子相关凋亡配体胞外功能区的原核表达质粒,优化诱导蛋白表达的相关条件,检测切胶纯化所得蛋白的抗原结合活性,以及亲和层析纯化蛋白的促凋亡功能。方法:扩增Trail胞外功能区第114-281个氨基酸基因序列,插入融合表达载体pET-28α(+)的多克隆位点,构建重组表达质粒pET-28α(+)-Trial114-281。以重组质粒转化大肠杆菌BL21(DE3),筛选阳性重组子,调整诱导前菌群的密度(A600)值,诱导时IPTG的浓度、温度及诱导时间,确定最佳诱导条件,同时比较超声、渗透冲击和IP裂解三种破碎细菌方法以及切胶回收和Ni-NTA亲和层析方法对纯化目的蛋白的影响。Western blot鉴定切胶纯化蛋白的抗原结合活性,用Ni-NTA亲和层析方法得到的蛋白作用于A549细胞,采用流式细胞术检测检测该细胞的凋亡率。结果:成功扩增了Trail胞外区基因序列,经测序证实其正确插入到表达载体pET-28α(+)中,经IPTG诱导,在37℃时呈包涵体表达,25℃时为可溶性表达,经软件分析确定A600=0.6,IPTG终浓度为0.6 mmol/L,诱导4 h为包涵体表达的最佳条件;A600=1.0,IPTG 1.0 mmol/L,诱导4 h为可溶性目的蛋白表达的最佳诱导条件。三种破菌方法的比较,超声法获得的蛋白最多。切胶和Ni-NTA亲和柱纯化的方法都得到了目的蛋白,Westernblot分析显示,切胶纯化的蛋白有较好的抗原结合活性,亲和层析得到的可溶性蛋白可以促使A549细胞发生凋亡。结论:成功构建了重组表达载体pET28α-Trial114-281,在A600值、IPTG以及诱导时间都相同的情况下,37℃出现包涵体表达,而25℃则出现了可溶性表达。切胶纯化获得蛋白有较好的抗原结合活性,亲和层析纯化的可溶性蛋白能保持其原有的功能不被破坏,促使肿瘤细胞A549的凋亡。  相似文献   

6.
目的构建及表达人cTnI(28-110aa)-linker-TnC融合蛋白。方法应用PCR技术从人心脏cDNA文库中扩增出cTnI(28-110aa)和TnC基因,通过引物设计在两者之间加上linker序列即编码19个中性氨基酸残基TS-(G4S)3-AC的序列,克隆PCR产物,并构建成pET28a-cTnI(28-110aa)-linker-TnC表达质粒,转化人大肠杆菌表达菌株BL21(DE3),用异丙基硫代-β-D-半乳糖苷(IPTG)诱导目的蛋白的表达,NTA树脂亲和层析纯化后检测其纯度和免疫反应性。结果成功构建了cTnI(28-110aa)-linker-TnC融合蛋白的基因,并在大肠杆菌中实现可溶性高表达,在摇瓶中的表达量为20mg/L.经一步NTA树脂亲和层析纯化,获得条带单一的目的蛋白,采用进口全自动免疫检测系统鉴定证实.目的蛋白有较高的免疫反应性。结论采用原核表达方法获得了具有高纯度和高免疫反应活性的cTnI(28-110aa)-linker-TnC融合蛋白。  相似文献   

7.
目的克隆人血红蛋白δ(delta)链蛋白基因,并在大肠杆菌中进行表达,经纯化与鉴定,获得δ链蛋白,为建立β-地中海贫血的免疫学筛查方法提供特异性抗原。方法从K562细胞中提取总RNA,采用RT-PCR技术获得目的片段并将其克隆到pET-32a及pET43.1a载体中,经PCR、酶切及测序验证,以IPTG诱导其在大肠杆菌中表达。包涵体经变性、复性后以Ni^2+亲和层析柱纯化,可溶性蛋白直接以Ni^2+亲和层析柱纯化。采用Western Blot和ELISA分析鉴定表达产物。结果成功构建两种融合表达载体pET32-Hbδ及pET43.1-Hbδ,分别为包涵体表达和可溶性表达,纯化产物经Western blotting和ELISA鉴定均为δ链蛋白。结论克隆表达并获得了纯化的人血红蛋白δ链,为后续的抗体制备及地中海贫血的免疫筛选方法的建立提供了抗原。  相似文献   

8.
目的构建编码截短型肿瘤抗原BAP31(△BAP31)与GST融合基因的原核表达载体,在大肠杆菌中表达并对融合蛋白(△BAP31/GST)进行纯化和初步鉴定。方法 PCR扩增编码△BAP31的基因片段,上下游分别引入EcoR I及Xho I酶切位点,亚克隆至含有GST标签的原核表达载体pGEX4T-1中,构建重组表达载体pGEX4T1-△BAP31,将该载体转化大肠杆菌DH5α,IPTG诱导表达△BAP31/GST,用GST亲和层析分离纯化原核表达的△BAP31/GST,表达产物分别用SDS-PAGE和West-ern blot进行鉴定。结果重组质粒经限制性内切酶EcoR I和Xho I双酶切鉴定和IPTG诱导表达△BAP31/GST的SDS-PAGE分析表明,表达产物的相对分子质量为40 000,与理论值相符,并主要以可溶性蛋白形式存在;经过对融合蛋白表达条件的优化,在IPTG浓度为1 mmol/L,诱导6 h目的蛋白表达量最高;灰度扫描分析发现,融合蛋白表达量占菌体蛋白总量的70.6%,纯化产物的纯度最高可达94.5%,Western blot证实该△BAP31/GST可与抗GST单克隆抗体(mAb)发生特异性结合反应,分子量为△BAP31与GST分子量之和,提示为融合蛋白。结论成功构建了编码△BAP31基因原核表达载体pGEX4T1-△BAP31,利用大肠杆菌表达系统和GST亲和层析,获得了较高纯度的△BAP31/GST融合蛋白,为进一步研究肿瘤抗原BAP31的功能及开发以BAP31作为靶点的肿瘤疫苗提供了试验基础。  相似文献   

9.
目的提高大鼠IgE依赖组胺释放因子(rHRF)的可溶性表达水平,改善其亲和层析纯化效果,为深入研究该重组蛋白的生物学功能奠定基础。方法选择多克隆酶切位点BamH Ⅰ和Xho Ⅰ,将rHRF完整编码区基因从原有的pET-30a—rHRF重组质粒亚克隆至pET-28a载体,构建重组质粒pET-28a-rHRF;转化大肠杆菌BL21(DE3)后,通过改变IPTG浓度(0.1~1.0mmol/L),调节诱导表达温度(25~370C)和时间(1-5h),筛选能够提高rHRF可溶性表达水平的条件;同时改进亲和层析纯化的条件,提高纯化效果。结果成功构建重组质粒pET-28a-rHRF,不同IPTG浓度、诱导温度和时间对重组蛋白的可溶性表达水平无明显影响。但是.与pET-30a-rHRF转化菌相比,pET-28a—rHRF转化菌所表达的重组蛋白因其N端和C端均带有6xhis标签.增强了目的蛋白与树脂的结合力,而使亲和层析纯化效果(重组蛋白的浓度和纯度)显著提高。结论rHRF重组蛋白的可溶性表达水平不受IPTG浓度、诱导表达温度和时间的影响,但是可溶性重组蛋白两端均携带6xhis标签可使亲和层析纯化效果显著提高,从而有利于获得足量rHRF用于进一步的生物学功能研究。  相似文献   

10.
蟑螂变应原Cr-PI包涵体的变复性研究   总被引:1,自引:0,他引:1  
本研究优化了GST CrPI融合蛋白在大肠杆菌中的诱导表达条件和GST CrPI包涵体的复性条件 ;采用GlutathioneSepharoseTM 4B亲和层析分离纯化融合蛋白 ,以Xa酶切去掉其GST标签后 ,对CrPI进行了电喷雾电离串联质谱分析 (ESI MS MS)。结果表明 ,IPTG浓度对该蛋白的诱导效果影响不大 ,OD6 0 0 值为 0 6时诱导效果最佳 ;复性蛋白浓度和L 精氨酸浓度对稀释复性结果有重要影响。纯化融合蛋白经Xa酶切、分子筛层析去掉GST标签后 ,重组蛋白的纯度达 95 % ,经质谱进一步鉴定为蟑螂CrPJ变应原  相似文献   

11.
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.  相似文献   

12.
Renal dysplasia and asplenia in two sibs   总被引:2,自引:0,他引:2  
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.  相似文献   

13.
About 1900, modern food selection and processing caused widespread 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 panhypovitaminosis B, i.e., a mixture of substrate beriberi and substrate pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse 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 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.  相似文献   

14.
15.
Newton H 《Medical history》2011,55(2):153-182
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.  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
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.  相似文献   

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