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1.
目的探讨骨髓间充质干细胞离体培养并与去抗原牛松质骨复合修复节段性骨缺损的效果.方法 Wistar大鼠骨髓间充质干细胞(MSCs)与去抗原牛松质骨(BCB)制成MSCs/ BCB复合物;采用同种异体大鼠桡骨干5mm节段性骨缺损动物模型,通过X线放射学、组织学、生物力学检测对比研究骨缺损修复情况.结果术后2、4、8、14、18周实验组与实验对照组经放射学检查评价新骨生成有显著性差异.术后组织学检查新骨生成速度、生成量均有显著性差异.18周经生物力学实验检测,实验组与实验对照组新骨生成有显著性差异, 实验组标本与正常基本一致.空白对照组各时间点均无新骨形成,最后缺损由纤维组织充填.结论大鼠骨髓间充质干细胞(MSCs)是骨组织工程中适宜的种子细胞.去抗原牛松质骨是可以选择的细胞载体.MSCs/BCB复合物植入修复骨缺损效果明显优于单纯BCB植入.  相似文献   

2.
目的 探讨骨髓间充质干细胞离体培养并与去抗原牛松质骨复合修复节段性骨缺损的效果。方法 Wistar大鼠骨髓间充质干细胞(MSCs)与去抗原牛松质骨(BCB)制成MSCs/BCB复合物;采用同种异体大鼠桡骨干5mm节段性骨缺损动物模型,通过X线放射学、组织学、生物力学检测对比研究骨缺损修复情况。结果 术后2、4、8、14、18周实验组与实验对照组经放射学检查评价新骨生成有显著性差异。术后组织学检查新骨生成速度、生成量均有显著性差异。18周经生物力学实验检测,实验组与实验对照组新骨生成有显著性差异,实验组标本与正常基本一致。空白对照组各时间点均无新骨形成,最后缺损由纤维组织充填。结论 大鼠骨髓间充质干细胞(MSCs)是骨组织工程中适宜的种子细胞。去抗原牛松质骨是可以选择的细胞载体。MSCs/BCB复合物植入修复骨缺损效果明显优于单纯BCB植入。  相似文献   

3.
背景:研究证实纳米晶胶原基骨复合间充质干细胞修复骨缺损具有体内成骨能力。 目的:观察血管内皮生长因子与骨髓间充质干细胞、纳米晶胶原基骨复合物修复大鼠股骨缺损的效果。 方法:制作SD大鼠股骨中段骨缺损模型,随机分为2组:对照组植入骨髓间充质干细胞/纳米晶胶原基骨复合物;实验组植入血管内皮生长因子/骨髓间充质干细胞/纳米晶胶原基骨复合物。术后第2,4,8周行股骨标本影像学与组织学观察;术后第8周行新生骨痂环境扫描电镜检查。 结果与结论:纳米晶胶原基骨支架复合物植入大鼠体内后无排斥反应及炎症反应,且血管内皮生长因子/骨髓间充质干细胞/纳米晶胶原基骨复合物成骨更快,较骨髓间充质干细胞/纳米晶胶原基骨复合物具有更好的骨再生能力,其成骨方式主要为软骨内成骨。推测血管内皮生长因子促进了局部微血管的形成和成骨细胞的分化、增殖,加快了软骨内成骨的速率,缩短了骨修复时间,提高了骨再生的质量和速率。  相似文献   

4.
背景:目前国内外已有关于人脐血间充质干细胞移植修复鼠脊髓损伤、脑肿瘤、心肌梗死等的报道,将其在特定的条件下向成骨细胞诱导分化的研究也已有报道,但尚未有将脐血间充质干细胞移植治疗动物骨坏死的研究报道。 目的:观察重组增强型绿色荧光蛋白慢病毒载体示踪转染的脐血间充质干细胞移植修复兔股骨头缺血性坏死的效果。 方法:含骨形态发生蛋白2基因质粒与携带重组增强型绿色荧光蛋白的慢病毒载体与脐血间充质干细胞共培养;制作兔股骨头缺损模型,随机分为3组,正常组未作任何处理,对照组骨缺损未进行填充;实验组骨缺损填充重组增强型绿色荧光蛋白慢病毒载体示踪转染的脐血间充质干细胞;分别于治疗4周和8周时股骨头行影像学和组织学观察。 结果与结论:影像学和组织学检查显示实验组治疗4周时即有明显的成骨反应和新骨形成,8周时基本修复股骨头的骨缺损区;对照组治疗4周时骨缺损为纤维结缔组织填充,8周时股骨头缺损周边骨质硬化,骨缺损处充填纤维结缔组织,股骨头骨小梁紊乱。结果显示重组增强型绿色荧光蛋白慢病毒载体示踪转染的脐血间充质干细胞有较强的诱导成骨作用,可以成功的修复股骨头缺损性坏死。  相似文献   

5.
背景:有研究表明骨髓间充质干细胞及异体骨可促进骨缺损的修复,但骨髓间充质干细胞复合异体骨对于松质骨缺损的修复效果至今少有报道。 目的:观察骨髓间充质干细胞复合异体骨修复兔松质骨缺损效果。 方法:在新西兰大白兔双侧股骨外侧髁造成0.6 cm×1.2 cm 的松质骨缺损,一侧设为模型组,骨缺损处植入复合骨髓间充质干细胞的异体骨,另一侧设为对照组,单纯植入异体骨。 结果与结论:植入后4,8,12周,大体观察、X射线检查和苏木精-伊红染色观察结果显示,模型组在新骨成长方面,缺损区修复方面均优于对照组。植入后12周,模型组骨缺损区可见大量骨小梁形成及成熟的板层骨组织,骨缺损基本修复。对照组骨缺损区仅可见大量编织骨形成,骨缺损尚未得到有效修复。模型组Lane-Sandhu法X射线结合组织学观察评分高于对照组(P < 0.05)。生物力学检测结果显示,植入后12周,模型组股骨髁最大压力载荷、载荷/应变比值均高于对照组(P < 0.05),最大应变位移较对照组低(P < 0.05)。结果证实,骨髓间充质干细胞复合异体骨可有效修复兔股骨髁松质骨缺损,且修复效果明显优于单纯异体骨移植。  相似文献   

6.
目的评价携带人骨形成蛋白-2(hBMP-2)基因重组腺病毒(Adv-hBMP-2)转染的骨髓基质干细胞(BMSCs)与透明质酸(HA)复合构建的组织工程化骨对兔桡骨干缺损的修复效果。方法取兔骨髓行BMSCs培养及Adv-hBMP-2的体外转染,建立兔桡骨干1.5cm的缺损模型。20只兔(40侧)分4组(n=10):第1组注射Adv-hBMP-2转染细胞+HA组,第2组注射Adv-hBMP-2转染细胞组,第3组单纯注射HA组、第4组空白对照组;通过影像学、组织学检查、生物力学测试和骨组织形态计量分析观察修复效果。结果(1)第1组,第12周8侧骨缺损中6侧完全愈合;第二组第12周8侧骨缺损中有3侧完全愈合;第3组和第4组,第12周骨缺损均未愈合。根据骨缺损内新生骨面积行X线疗效评分,各组依次为4.63±0.74、3.38±1.60、1.63±0.74、1.50±0.53,差异有统计学意义(P<0.0001)。(2)第1、2组,4 ̄8周时骨缺损内均有多量新生骨痂形成,12周时部分骨髓腔再通;第3、4组,4 ̄8周时骨缺损处为纤维组织填充,12周时骨缺损未愈合,两骨端硬化。新生骨小梁面积第1、2组分别为(16.25±3.49)mm2、(10.37±2.02)mm2,差异有统计学意义(P<0.001)。(3)第1组的最大压缩载荷和弹性模量分别为(211.54±63.58)N和(113.36±56.47)MPa,第2组分别为(126.74±53.13)N和(98.91±63.36)MPa,差异有统计学意义(P<0.05)。平均最大压缩载荷与正常桡骨组之比:前者为75.86%,后者为45.45%。结论HA复合Adv-hBMP-2转染BMSCs构建的组织工程化骨可以修复兔桡骨干骨缺损。  相似文献   

7.
背景:以往研究表明羟基磷灰石复合骨髓间充质干细胞具有良好的骨缺损修复效果,但这种复合材料在冻存后是否具有骨缺损修复效果还不清楚。 目的:观察深低温冻存羟基磷灰石/骨髓间充质干细胞复合修复骨缺损的效果。 方法:制备27只日本大耳白兔桡骨10 mm缺损模型,随机分为冻存复合材料组、新鲜复合材料组与羟基磷灰石组,3组分别于骨缺损处植入-80 ℃保存3个月的羟基磷灰石/同种异体骨髓间充质干细胞复合物、新鲜制备的羟基磷灰石/同种异体骨髓间充质干细胞复合物及单纯羟基磷灰石,植入后8,12周行大体观察、X射线观察及苏木精-伊红染色等组织学观察,并于12周行生物力学检测。 结果与结论:术后12周,冻存复合材料组、新鲜复合材料组骨缺损大部分愈合,有成熟骨小梁通过,有的可见髓腔通畅,塑形较好;羟基磷灰石组骨痂生成少,骨缺损部分愈合,塑形欠佳,新骨生成少于冻存复合材料组、新鲜复合材料组(P < 0.05)。冻存复合材料组、新鲜复合材料组最大载荷明显大于羟基磷灰石组(P < 0.05)。表明低温冻存羟基磷灰石/骨髓间充质干细胞复合植骨材料的骨缺损修复能力与新鲜制作的复合材料几乎一致,未因冻存受到影响。  相似文献   

8.
背景:前期实验已成功将骨髓间充质干细胞接种于磷酸钙骨水泥支架,并证实其具有良好的机械强度和生物相容性。目的:观察新西兰大白兔骨髓间充质干细胞体外培养后与磷酸钙骨水泥复合修复关节软骨缺损的可行性。方法:选取18只新西兰兔用电钻制成股骨滑车部5 mm的骨-软骨缺损模型,随机选择15只兔于骨缺损处左侧植入单纯磷酸钙骨水泥材料作为对照组,于右侧植入骨髓间充质干细胞与磷酸钙骨水泥复合物作为实验组,另3只兔不植入任何材料作为空白组。分别于4,8,16周各时间点处死兔取材,进行X射线摄片、组织形态学观察及生物力学检测。结果与结论:术后4,8,16周各组骨缺损均有不同程度的骨再生,实验组新骨形成的速度和数量均优于其他组,组织学观察到实验组的成骨细胞及骨小梁出现均早于其他组。术后16周实验组骨标本抗弯曲能力的最大负荷、最大应力和破坏能量均明显高于对照组(P0.05)。结果表明骨髓间充质干细胞复合磷酸钙骨水泥材料修复骨缺损可促进骨组织再生,恢复骨的刚度和强度,有望作为一种新型人工骨材料。  相似文献   

9.
目的:探讨大鼠骨基质明胶吸附骨髓间充质干细胞修复骨缺损的可行性。方法:采用第5代(P5)SD大鼠骨髓间充质干细胞(MSCs),经Hoeschst 33344(sigma)荧光杂料标记后,调配制成的1×106个/ml细胞浓度后与骨基质明胶(BMG)共同培养6 h,然后植入SD大鼠双侧胫骨的实验性骨缺损中(A组),同时作胫骨骨缺损单纯BMG植入(B组),无植入物(C组)两组对照。术后8周处死,取骨缺损区组织进行组织学观察,其中A组行荧光染料标记测定以确认骨缺损区的骨痂是否来源于MSCS。结果:①A组:胫骨骨缺损区可见大量新生不规则骨纤维组织、软骨及纤维骨痂填充,可见骨细胞、骨组织和骨小梁,已形成骨髓腔。②B组:胫骨骨缺损区可见大量纤维组织、少量新生不规则骨纤维组织及骨骼肌组织,伴有多核巨细胞和少量炎性细胞,缺损区边缘带有骨痂组织。③C组:胫骨骨缺损区可见大量纤维组织及骨骼肌组织填充生长,伴有多核巨细胞和少量炎性细胞,缺损区边缘带有少量骨痂组织。荧光染色鉴定确认胫骨骨缺损区的骨痂来源于MSCs。结论:大鼠骨基质明胶吸附骨髓间充质干细胞修复骨缺损具有安全性、可行性及有效性。  相似文献   

10.
背景:人脐带间充质干细胞在成骨及组织器官修复方面具有更强的扩增能力及低免疫原性,其成集落生长潜能及成骨时间早于骨髓等其他来源间充质干细胞。 目的:观察脐带间充质干细胞诱导成骨及移植治疗骨缺损的临床效果。 方法:应用组织块贴壁法提取人脐带间充质干细胞,体外行成骨诱导并通过光镜观察、茜素红染色、碱性磷酸酶染色、Ⅰ型胶原的表达等证实其体外成骨能力;对临床骨缺损病例行人脐带间充质干细胞移植,移植后定期复查骨缺损部骨痂生长状况。   结果与结论:体外诱导证实人脐带间充质干细胞具有明确的成骨作用。骨缺损患者在人脐带源间充质干细胞移植后2个月X射线见左股骨髁上骨折部位骨块间隙模糊,骨折外周形成明显的骨痂,骨折断端相连,断端骨折线依然存在;移植后3个月见骨痂间已经形成明显骨性连接。证实脐带间充质干细胞具有体外诱导成骨及体内移植修复骨缺损作用。  相似文献   

11.
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   

12.
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   

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.
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.  相似文献   

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16.
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   

17.
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   

18.
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   

19.
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   

20.
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   

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