硫酸软骨素酶ABC对大鼠脊髓损伤修复的影响

为了探讨硫酸软骨素酶ABC对脊髓损伤后损伤局部瘢痕形成和脊髓传导功能修复的影响,本研究首先制作大鼠脊髓全横断损伤动物模型,并将其分为脊髓损伤组(A组)和脊髓损伤治疗组(B组)。在观察期内对动物的行为学表现进行BBB评分;用免疫荧光组织化学方法观察损伤4周后硫酸软骨素酶ABC对损伤局部的硫酸软骨素蛋白聚糖(CSPGs)的裂解作用;用辣根过氧化物酶(HRP)示踪法观察损伤8周后神经纤维的再生情况。结果显示:A组与B组之间动物的行为学评分B组优于A组,有显著性差异(P<0.01);B组动物脊髓内硫酸软骨素蛋白聚糖阳性物质的表达明显低于A组,具有显著性差异(P<0.05),而硫酸软骨素核心蛋白的表达无显著性差异(P>0.05);HRP示踪法显示B组脊髓损伤头端可见少量HRP标记的神经元胞体和纤维。本研究结果提示硫酸软骨素酶ABC能够裂解CSPGs中的葡胺聚糖链,减少瘢痕,促进损伤的神经纤维再生。     

硫酸软骨素蛋白多糖对视皮层γ-氨基丁酸能神经元表达及其抑制性突触传递功能的影响

目的:通过体外观察硫酸软骨素蛋白多糖(CSPGs)对γ-氨基丁酸(GABA)能神经元表达及其抑制性突触传递功能的影响,为探索CSPGs抑制视皮层可塑性的机制提供实验依据。方法:运用硫酸软骨素酶(ChABC)处理体外培养的胎鼠视皮层神经元,降解其CSPGs后应用免疫荧光显色检测CSPGs降解情况及GABA能神经元的表达变化,并用膜片钳检测其自发性微小性抑制性突触后电流(mIPSCs)以观察其抑制性突触传递功能变化情况。结果:0.1 U/ml ChABC处理神经元后,CSPGs被成功降解,GABA能神经元细胞密度、mIPSCs幅度和频率均显著低于正常对照组。结论:CSPGs能促进GABA能神经元表达及其抑制性突触传递功能的成熟,这可能是CSPGs抑制视皮层可塑性的作用机制之一。     

大鼠脊髓半横断损伤后硫酸软骨素蛋白多糖Versican的变化

目的观察大鼠脊髓半横断损伤(hSCI)位点头尾段硫酸软骨素蛋白多糖Versican的表达变化,探讨其与脊髓损伤修复的关系。方法20只成年健康SD大鼠随机分为假手术对照组和脊髓半横断损伤3d、7d和14d组。建立成年SD大鼠脊髓半横断(T9～T10)模型。取损伤位点头尾段T9、T10节段制作冰冻切片,运用Versican抗血清进行免疫组化ABC法染色。分别观察并计数各组前角中Versican阳性细胞数,采用计算机图像分析技术测量免疫阳性产物的平均光密度(A)值。结果Versican阳性产物主要分布于细胞外基质中,前角神经元和胶质细胞的胞浆中也有分布;损伤后前角中Versican阳性神经元和胶质细胞数较对照组明显减少(P<0.05),免疫阳性产物平均A值较对照组明显增加(P<0.05)。结论脊髓半横断损伤后,表达增加的Versican很可能参与损伤后轴突生长被抑制的过程。     

硫酸软骨素酶联合脂肪间充质干细胞治疗大鼠视网膜变性北大核心

背景:有研究发现硫酸软骨素酶降解硫酸软骨素蛋白多糖能够促使视网膜上Müller细胞的移行,但硫酸软骨素酶降解硫酸软骨素蛋白多糖是否能促进脂肪间充质干细胞在视网膜变性大鼠视网膜的移行尚不明确。目的:探讨硫酸软骨素酶降解硫酸软骨素蛋白多糖对脂肪间充质干细胞治疗大鼠视网膜变性的影响。方法:分离并培养人脂肪间充质干细胞,建立视网膜变性大鼠模型,向视网膜变性大鼠视网膜下腔注射脂肪间充质干细胞+硫酸软骨素酶,观察移植后大鼠脂肪间充质干细胞迁移率和视网膜细胞凋亡情况。结果与结论:人脂肪间充质干细胞能够成功培养,Brd U对人脂肪间充质干细胞的标记率达90.0%以上。建模后7 d,视网膜外核层塌陷,光感受器细胞大量外节迸解,外核层贴附在Bruch’s膜上,视网膜呈拱桥样,中央视网膜和外周视网膜均受到损伤;正常大鼠视网膜各层清晰,光感受器细胞排列规律,视网膜色素上皮层完整。脂肪间充质干细胞+硫酸软骨素酶组脂肪间充质干细胞迁移率高于脂肪间充质干细胞组,且2组视网膜细胞凋亡率比较差异无显著性意义。表明硫酸软骨素酶降解硫酸软骨素蛋白多糖可提高人脂肪间充质干细胞在视网膜上的迁移能力。     

硫酸软骨素酶ABC联合高压氧预处理对脊髓损伤大鼠后肢运动功能的影响

目的探讨硫酸软骨素酶ABC(ChABC)联合高压氧预处理对成年大鼠脊髓损伤后不同时期后肢运动功能及腓肠肌运动终板内乙酰胆碱酯酶(AChE)含量的影响。方法雌性成年Wistar大鼠80只,体重250～300g,随机分为假手术组(Sham组)、脊髓损伤组(SCI组)、高压氧预处理组(HBOP组)、高压氧预处理后硫酸软骨素酶ABC治疗组(HBOP+ChABC组)各20只。采用脊髓半横断法制作模型,分别于伤后3d、7d、14d和28d随机选取5只大鼠,采用BBB评分(Basso,Beattie and Bresnaban score)法进行行为学观察,评分后经灌注固定,取大鼠患侧下肢腓肠肌,进行酶化学染色并应用Image-Pro Plus 6.0图像分析系统测量腓肠肌中AChE染色阳性部位平均光密度值(AOD值)。结果 Sham组大鼠BBB评分及AChE活性明显高于SCI组(P<0.01),HBOP组与HBOP+ChABC组在术后14d之后BBB评分明显高于SCI组(P<0.05),CHABC+HBOP组在术后28天BBB评分高于HBOP组(P<0.05)。HBOP组患侧腓肠肌AchE活性高于SCI组,HBOP+ChABC组高于HBOP组(P<0.05)。结论高压氧预处理可以改善大鼠患肢的运动功能和提高AChE的活性,联合硫酸软骨素酶ABC作用更强。     

硫酸软骨素酶ABC在中枢神经系统中促进神经再生的作用

中枢神经系统(CNS)损伤后因胶质瘢痕形成而导致神经元的轴突不能再生,功能恢复不良.胶质瘢痕的重要组分是硫酸软骨素蛋白聚糖(CSPGs),其单独或与其它细胞外基质结合,导致向损伤部位延伸的轴突在胶质瘢痕处停止,而且CSPGs在神经再生时间窗关键期末可降低轴突生长的可塑性.近年研究发现硫酸软骨素酶ABC(chondroi...     

硫酸软骨素蛋白多糖与中枢神经可塑性

硫酸软骨素蛋白多糖不仅影响中枢神经系统的发育成熟 ,也作为神经抑制因素参与成年期中枢神经系统损害后的神经可塑性过程 ,并调节成年神经再生。研究硫酸软骨素蛋白多糖和神经可塑性的相互关系及影响因素 ,有助于指导中枢神经系统损害后的康复治疗。     

督脉电针联合神经干细胞移植治疗脊髓全横断损伤后aggrecan的表达变化

目的:观察督脉电针联合神经干细胞( NSCs)移植治疗脊髓损伤对硫酸软骨素蛋白多糖aggrecan的表达影响.方法:成年SD大鼠随机分为脊髓损伤对照组、督脉电针组、NSCs移植组以及督脉电针联合NSCs移植组.建立成年大鼠第9～10胸椎段脊髓全横断模型.其中电针组和电针联合NSCs组于术后当天进行电针治疗.用免疫组织化...     

硫酸软骨素蛋白聚糖与脊髓损伤轴突再生

脊髓损伤后传导束的纤维不能有效再生是脊髓损伤后修复与功能重建的难点之一，其中屏障之一是神经胶质瘢痕，主要由星形胶质细胞和硫酸软骨素蛋白聚糖（chondroitin sulfate proteoglycans，CSPGs）组成，轴突不能穿过神经胶质而再生，屏障导致营养不良，再生受阻。目前有关胶质瘢痕的形成过程与调控、CSPGs参与胶质瘢痕形成的机制、以及如何有效地控制瘢痕的形成从而促进轴突再生，仍存在许多未知领域。     

大鼠脊髓半横断损伤后Versican及其受体CD44的表达变化

目的探讨大鼠脊髓半横断(hemisected spinal cord injury,hSCI)损伤后14d硫酸软骨素蛋白多糖Versi-can及其受体CD44的表达变化。方法10只成年SD大鼠随机分为正常对照组和术后14d组。建立成年SD大鼠脊髓半横断(T9~T10)模型。14d后取损伤位点头尾段T9、T10节段制作冰冻切片,运用Versican、CD44抗血清进行免疫组化ABC法染色。分别观察并计数脊髓腹角和Ⅰ、Ⅱ板层内Versican、CD44的免疫反应阳性细胞数。结果Ver-sican主要分布于正常大鼠脊髓腹角,CD44主要分布于正常大鼠脊髓Ⅰ、Ⅱ板层和腹角。损伤后14d腹角Versican阳性细胞数较正常组明显下降(P<0.05),Ⅰ、Ⅱ板层和腹角的CD44阳性细胞数也较正常组明显下降(P<0.05)。而手术组损伤侧与未损伤侧Versican和CD44表达水平均无明显差异(P>0.05)。结论大鼠脊髓半横断损伤14d后Versican、CD44表达均明显下降,提示脊髓半横断损伤对脊髓灰质内细胞表达Versican、CD44有影响。     

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.