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1.
目的探讨同型半胱氨酸(homocysteine,Hcy)水平及亚甲基四氢叶酸还原酶(methylenetetrahydrofolate reductase,MTHFR)基因多态性与缺血性卒中(ischemic stroke,IS)的关系,并分析Hcy与叶酸、Vit B_(12)之间的相关性。方法运用酶循环法和聚合酶链式反应(polymerase chain reaction,PCR)-芯片杂交法分别检测217例IS患者和223例对照者血浆Hcy与MTHFR C667T基因型,并对照分析两组的基因型频率和等位基因频率分布差异及血浆Hcy水平;运用免疫分析法检测两组中既往未服用过含叶酸和Vit B_(12)药物的88例IS患者和125例对照者血清叶酸、Vit B_(12)水平,并与Hcy水平进行相关性分析。结果 IS组Hcy浓度高于对照组,差异有显著性([23.95±12.13)μmol/L vs(17.31±7.20)μmol/L,t=29.61,P0.001],IS组与对照组MTHFR基因型频率CC、CT、TT型分别为14.3%、44.7%、41.0%和18.4%、48.9%、32.7%,等位基因C与T的频率分别为36.6%、63.4%和42.8%、57.2%,无显著性差异(基因型频率:χ~2=3.59,P=0.166;基因频率:χ~2=3.52,P=0.061)。MTHFR基因TT型(162例)、CT型(206例)和CC型(72例)的血浆Hcy水平分别为(25.19±12.53)μmol/L、(18.21±8.08)μmol/L和(16.65±6.90)μmol/L,其中TT型显著高于CT型和CC型,CT型显著高于CC型(P均0.001)。IS组和对照组血浆Hcy水平与Vit B_(12)呈负相关(IS组和对照组分别为r=-0.431,P0.001和r=-0.507,P0.001),与叶酸亦呈负相关(IS组和对照组分别为r=-0.489,P0.001和r=-0.446,P0.001)。结论 IS患者血浆Hcy水平较正常人偏高;MTHFR C667T基因突变、叶酸和Vit B_(12)水平降低是血浆Hcy水平升高的影响因素;MTHFR C667T基因突变可能与缺血性卒中无关。  相似文献   

2.
目的 探讨亚甲基四氢叶酸还原酶(MTHFR) C677T突变基因与血管性认知功能障碍(VCI)的关系.方法 采用酶联免疫法测定血浆同型半胱氨酸(Hcy)浓度,应用聚合酶链反应-限制性内切酶片段长度多态性技术检测143例VCI患者、122例无认知损害脑梗死患者及140例正常对照的MTHFR C677T基因型.结果 (1)VCI组、脑梗死组和对照组的血浆同型半胱氨酸(Hcy)平均水平分别为(12.257±3.595) μmol/L、(11.028 ±3.198)μmol/L、(9.784±3.074) μmol/L,两病例组Hcy水平明显高于正常对照组(P<0.05);(2)3组研究对象的TT基因型分布有明显差异(x2=19.464,P<0.01),CT型及CC型分布无差异(P>0.05);VCI组及脑梗死组的T等位基因发生频率明显高于正常对照组(P<0.05),相对危险度分别为1.79和1.47;(3)VCI组、脑梗死组及正常对照组中,MTHFR基因有C677T突变者(尤其TT型者)血浆Hcy水平均显著高于无基因突变者.结论 血浆Hcy水平升高是VCI和脑梗死共同的致病基础;MTHFR C677T基因突变致血浆Hcy水平升高可能是VCI发病的重要遗传因素.  相似文献   

3.
目的探讨同型半胱氨酸(Hcy)水平及亚甲基四氢叶酸还原酶(MTHFR)基因多态性与河南汉族人群脑梗死的相关性。方法运用循环酶法和PCR-限制性片段长度多态性分析检测河南汉族300例脑梗死患者及261例健康对照者Hcy水平及MTHFR C677T基因型,并进行测序验证。结果病例组和对照组平均空腹血浆Hcy水平差异有显著性(P<0.01);MTHFR C677T在患者组TT型、CT型频率及T等位基因频率均显著高于对照组,差异有统计学意义(P<0.01);两组不同基因型相应的Hcy浓度差异有统计学意义(P<0.01),TT型与CT型显著高于CC型(P<0.01)。Logistic回归分析结果显示:在调整传统危险因素后,MTHFR C677T基因突变及升高的Hcy水平和脑梗死发病相关。结论血浆Hcy浓度升高是河南汉族脑梗死的独立危险因素;MTHFR C677T基因突变可影响Hcy水平,可能是脑梗死发生的重要机制之一。MTHFR基因突变可能是河南汉族人群中脑梗死发病中的一个重要危险因素。  相似文献   

4.
目的探讨中青年脑卒中与血浆同型半胱氨酸(homocysteine Hcy)水平及亚甲基四氢叶酸还原酶(methylenetetrahydrofolate reductase MTHFR)基因多态性的关系.方法利用多聚酶链反应-限制性内切酶片段长度多态性技术(PCR-PFLP)分析73例中青年脑卒中患者及134例老年脑卒中患者与27例中青年及38例老年正常对照人群MTHFR基因突变情况,并应用高效液相色谱(HPLC)法检测其血浆Hcy水平、放射免疫法测定叶酸、VitB2水平加以对照分析.结果中青年脑卒中组血浆Hcy水平(22.36±10.99μmol/L)及老年脑卒中组血浆Hcy水平(19.41±10.32μmol/L)均高于各自对照组(11.49±5.05μmol/L)及(12.26±5.24μmol/L),差异有显著性(P<0.01),且中青年脑卒中组中血浆Hcy升高的比例(58%)显著高于老年脑卒中组(43%)(x2=4.69,P<0.05).MTHFR有三种基因型,中青年脑卒中组及对照组C/C型C/T型T/T型分别为(0.25、0.44、0.31)及(0.52、0.32、0.16),两组相比差异有显著性(x2=8.51,P<0.05);而老年脑卒中组及对照组分别为(0.35、0.46、0.19)及(0.52、0.32、0.16),两组相比无显著差异(x2=3.96,P>0.05).各组MTHFR的T/T基因型血浆Hcy水平与C/C型比较有显著差异(P<0.01),两脑卒中组MTHFR的C/T基因型血浆Hcy水平与C/C型比较也有显著差异(P<0.05),且叶酸VitB12水平较各自对照组显著下降(P<0.01),老年脑卒中组较中青年组叶酸水平降低更显著(P<0.05).结论血浆Hcy水平升高是脑血管病的重要危险因索,MTHFR基因突变及叶酸VitB12变化均是血浆Hcy升高的重要影响因素,对于中青年患者意义更大.  相似文献   

5.
亚甲基四氢叶酸还原酶基因多态性与脑梗死的关系   总被引:1,自引:0,他引:1  
目的 再一次探讨亚甲基四氢叶酸还原酶(MTHFR)基因多态性及血浆同型半胱氨酸(Hcy) 与脑梗死的相关性.方法 采用聚合酶链反应-限制性内切酶长度多态性(PCR-RFLP)方法分析脑梗死病人(260例)与健康人群(242例)的MTHFR基因突变的情况.利用高效液相色谱法测定血浆Hcy水平,并加以对照分析.结果 脑梗死组与对照组MTHFR基因型比较无统计学意义(P=0.140).2组MTHFR的T等位基因频率相比亦无统计学意义(P=0.061).2组Hcy水平比较差异有统计学意义(P<0.001),Hcy水平与叶酸呈负相关.结论 进一步证实血浆Hcy水平升高是脑梗死的独立危险因素,MTHFR基因突变可能是Hcy升高的主要影响因素.  相似文献   

6.
脑动脉狭窄与同型半胱氨酸和MTHFR基因多态性的关系   总被引:4,自引:0,他引:4  
目的探讨血浆同型半胱氨酸(Hcy)和5,10-亚甲基四氢叶酸还原酶(MTHFR)两个常见突变位点与脑动脉狭窄的关系。方法选择年龄、性别匹配的病例组80例,对照组55例,采用荧光偏振免疫法(FPIA)测定血浆Hcy水平,聚合酶链反应-限制片段长度多态性(PCR-RFLP)技术进行基因分型。结果病例组和对照组血浆Hcy水平分别为17.18μmol/L和12.54μmol/L,差别显著(P<0.05)。血浆Hcy水平与血管狭窄数目无关。两组MTHFR677TT及T等位基因频率差异均显著(P<0.05),1298AC/CC及C等位基因频率、677CT/1298AC频率均无显著差异。各组内677TT Hcy水平显著高于677CT或677CC型,A1298C突变对Hcy水平无明显影响。结论677TT突变可引起血浆Hcy水平显著升高,与脑动脉狭窄密切相关。A1298C突变对血浆Hcy水平及脑动脉狭窄无显著影响。  相似文献   

7.
MTHFR基因多态性及同型半胱氨酸与青年脑血管病的关系   总被引:4,自引:0,他引:4  
目的:研究Ns,N10-亚甲基四氢叶酸还原酶(MTHFR)基因多态性及血浆同型半胱氨酸(Hcy)水平与青年脑血管病的关系。方法:研究对比40例青年脑血管病患者(首次发病年龄≤50岁)及32例健康青年人的MTHFR基因多态性及血浆Hcy水平。结果:(1)对照组及病例组T/T纯合子率分别为37.5%和22.5%;T等位基因频率分别为60.9%和51.3%,差异均无显著统计意义(均P>0.05)。(2)病例组血浆Hcy几何均值(11.0±2.3μmol/L)显著高于对照组(8.0±1.4μmol/L,P<0.05)。(3)所有受试者中T/T组Hcy值高于C/C组(10.4μmol/L和7.6μmol/L),但差异无显著性(P>0.05)。结合叶酸考虑,进一步将所有受试者按叶酸中位数水平分组。叶酸中位数以下组中,T/T组Hcy值显著高于C/C组(P<0.05);而叶酸中位数以上组中,T/T组Hcy值与C/C组无显著差异。(4)血浆Hcy与叶酸、维生素B12呈显著负相关,与肌酐呈显著正相关。吸烟者血浆Hcy水平显著高于不吸烟者(P<0.05)。结论:(1)本组人群MTHFR基因C677T突变的纯合子在低叶酸状态下可引起血浆Hcy水平显著增高,但与青年脑血管病无显著关系。MTHFR基因677TT纯合突变可能为健康青年人脑血管的保护因素。(2)血浆Hcy水平与青年脑血管病的发生密切相关。(3)叶酸、维生素B12肌酐、吸烟是Hcy的非遗传影响因素。  相似文献   

8.
目的探讨同型半胱氨酸(Hcy)水平与性别、高血压和亚甲基四氢叶酸还原酶(MTHFR)基因的关系。方法检测229例脑梗死患者和111例非脑梗死患者的血清Hcy水平和MTHFR基因型,比较血清Hcy在不同性别、高血压及MTHFR基因型患者之间的差别。结果脑梗死组T等位基因频率显著高于非脑梗死组(χ^2=4.98,P=0.026)。脑梗死组中,TT基因型患者的Hcy水平显著高于CC和CT基因型患者(P<0.05~0.01)。非脑梗死组中,TT基因型患者的Hcy水平显著高于CC和CT基因型的患者(均P<0.01)。脑梗死组CC、CT、TT基因型患者的Hcy水平均显著高于非脑梗组(t=4.21,P<0.01;t=4.20,P<0.01;t=2.20,P=0.033)。两组间高血压患者的Hcy水平均显著高于无高血压患者(均P<0.01),男性Hcy水平均显著高于女性(均P<0.01)。结论脑梗死患者具有较高的T等位基因频率。TT基因型、男性、高血压患者具有较高的Hcy水平。  相似文献   

9.
目的研究血浆同型半胱氨酸(Hcy)浓度及亚甲基四氢叶酸还原酶(MTHFR)基因多态性与血管性痴呆(VaD)的关系。方法选取83例VaD患者作为观察组和81例非痴呆脑梗死患者作为对照组,分别测定两组患者的MTHFR基因多态性、Hcy浓度、维生素B12和叶酸水平,根据简易精神状态检查量表(MMSE)评定VaD患者痴呆程度,对指标进行比较和相关性分析。结果 MTHFR基因TT纯合子在观察组VaD患者的分布频率明显高于对照组,差异具有统计学意义(P0.05);两组患者的MTHFR基因C、T等位基因分布频率差异具有统计学意义(P0.05)。观察组VaD患者的血浆Hcy浓度明显高于对照组,其血清叶酸与维生素B12浓度明显低于对照组,VaD患者的血浆Hcy水平随着痴呆程度的增加而明显提高,差异均具有统计学意义(P0.05)。VaD患者血浆Hcy水平与自身痴呆程度呈正相关(r=0.452,P0.05),与MMSE评分呈负相关(r=-0.246,P0.05)。结论MTHFR基因C677T突变及高水平Hcy与VaD的发生、发展相关,高Hcy血症是VaD发病的一个重要因素。  相似文献   

10.
目的探讨MTHFR C677T基因多态性、同型半胱氨酸(Hcy)水平对2型糖尿病患者发生脑梗死的影响。方法采用病例-对照研究。随机选取422例研究对象,分为正常对照组(n=111)、脑梗死组(n=155)、2型糖尿病合并脑梗死组(n=156)。PCR-芯片法测定MTHFR基因型,循环酶法检测血清Hcy水平。运用SPSS25.0软件比较各组间MTHFR基因型分布情况及不同基因型患者的Hcy水平。结果各实验组和正常对照组相比,MTHFR基因型分布、等位基因T频率差异均具有统计学意义(x~2=7.023~7.52,P0.05;x~2=3.875~6.262,P0.05)。糖尿病合并脑梗死组和脑梗死组相比,MTHFR基因型分布差异无统计学意义(x~2=1.761,P=0.415),但Hcy水平差异有统计学意义(P0.001)。其中糖尿病合并脑梗死组TT型患者血浆Hcy水平显著低于脑梗死组(P0.001)。结论 MTHFR基因多态性可能为脑梗死的危险因素。TT型糖尿病合并脑梗死患者相对于该基因型单纯脑梗死患者Hcy水平更低。  相似文献   

11.
Neurons in the deeper layers of the superior colliculus (SC) have spatially tuned receptive fields that are arranged to form a map of auditory space. The spatial tuning of these neurons emerges gradually in an experience-dependent manner after the onset of hearing, but the relative contributions of peripheral and central factors in this process of maturation are unknown. We have studied the postnatal development of the projection to the ferret SC from the nucleus of the brachium of the inferior colliculus (nBIC), its main source of auditory input, to determine whether the emergence of auditory map topography can be attributed to anatomical rewiring of this projection. The pattern of retrograde labeling produced by injections of fluorescent microspheres in the SC on postnatal day (P) 0 and just after the age of hearing onset (P29), showed that the nBIC-SC projection is topographically organized in the rostrocaudal axis, along which sound azimuth is represented, from birth. Injections of biotinylated dextran amine-fluorescein into the nBIC at different ages (P30, 60, and 90) labeled axons with numerous terminals and en passant boutons throughout the deeper layers of the SC. This labeling covered the entire mediolateral extent of the SC, but, in keeping with the pattern of retrograde labeling following microsphere injections in the SC, was more restricted rostrocaudally. No systematic changes were observed with age. The stability of the nBIC-SC projection over this period suggests that developmental changes in auditory spatial tuning involve other processes, rather than a gross refinement of the projection from the nBIC.  相似文献   

12.
The distribution of labelled cells and of extracellular granules in the claustrum has been studied after injections of horseradish peroxidase in several areas of the neocortex. The frontal and parietal lobes are related to the anterior and posterior halves respectively of the claustrum, and the occipital and temporal cortex to the posterior and inferior margins. Parts of the claustrum related to areas of the cortex in the frontal lobe overlap considerably in the antero-posterior dimension with parts related to widely separated but interconnected areas of the parieto-temporal cortex. Areas of cortex within one lobe which are interconnected are related to parts of the claustrum which overlap in the dorsoventral dimension.  相似文献   

13.
Robert M. Beckstead   《Brain research》1984,300(2):351-356
Injections of wheat germ agglutinin-conjugated horseradish peroxidase in the lateral part of the caudate nucleus or the putamen of the cat result in retrograde thalamic cell-labeling in the rostral extension of the medial subdivision of the posterior group (POM). Autoradiography after [3H]amino acid injection of POM reveals a dense and discontinuous distribution of axons in the lateral half of the caudate and putamen concentrated at their middle rostrocaudal levels. This newly discovered thalamostriatal projection of POM may account for somatosensory activity observed in striatal cells.  相似文献   

14.
The amygdala of all tetrapod vertebrates receives direct projections from the main and accessory olfactory bulbs, and the strong similarities in the organization of these projections suggest that they have undergone a very conservative evolution. However, current ideas about the function of the amygdala do not pay sufficient attention to its chemosensory role, but only view it as the core of the emotional brain. In this study, we propose that both roles of the amygdala are intimately linked since the amygdala is actually involved in mediating emotional responses to chemical signals. The amygdala is the only structure in the brain receiving pheromonal information directly from the accessory olfactory bulbs and we have shown in mice that males emit sexual pheromones that are innately attractive for females. In fact, sexual pheromones can be used as unconditioned stimuli to induce a conditioned attraction to previously neutral odorants as well as a conditioned place preference. Therefore, sexual pheromones should be regarded as natural reinforcers. Behavioural and pharmacological studies (reviewed here) have shown that the females' innate preference for sexual pheromones is not affected by lesions of the dopaminergic cells of the ventral tegmental area, and that the systemic administration of dopamine antagonists do not alter neither the attraction nor the reinforcing effects of these pheromones. Anatomical studies have shown that the vomeronasal amygdala gives rise to important projections to the olfactory tubercle and the islands of Calleja, suggesting that these amygdalo-striatal pathways might be involved in the reinforcing value of sexual pheromones.  相似文献   

15.
We investigated whether the heart receives collateral projections from the neurons which innervate the esophagus with a retrograde double-labeling method using two fluorescent tracers. Following injections of True Blue (TB) into the esophagus and Diamidino Yellow (DY) into the heart, about 21.9% of the labeled esophageal motoneurons in the compact formation of the nucleus ambiguus (AmC) were retrogradely double labeled. No single-labeled cardiac motoneurons were found in the AmC. The present results provide anatomical substrates for the esophagocardiac reflex.  相似文献   

16.
Electrophysiological experiments were performed on anesthetized rats to determine the effects of lesions of the paraventricular nucleus on the amplitude of evoked potentials recorded in the periglomerular layer of the olfactory bulb after nucleus of the solitary tract electrical stimulation. Lesions of the paraventricular nucleus enhance the amplitude of both the positive and negative components of the evoked potential in the olfactory bulb. The pathway from the paraventricular nucleus to the olfactory bulb seems to exert a suppressive influence over the projection from the nucleus of the solitary tract to the olfactory bulb under these conditions.  相似文献   

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The orbital cortex (ORB) of the rat consists of five divisions: the medial (MO), ventral (VO), ventrolateral (VLO), lateral (LO), and dorsolateral (DLO) orbital cortices. No previous report has comprehensively examined and compared projections from each division of the ORB to the thalamus. Using the anterograde anatomical tracer, Phaseolus vulgaris leucoagglutinin, we describe the efferent projections from the five divisions of the ORB to the thalamus in the rat. We demonstrated that, with some overlap, each division of the ORB distributed in a distinct (and unique) manner to nuclei of the thalamus. Overall, ORB projected to a relatively restricted number of sites in the thalamus, and strikingly distributed entirely to structures of the medial/midline thalamus, while completely avoiding lateral regions or principal nuclei of the thalamus. The main termination sites in the thalamus were the paratenial nucleus (PT) and nucleus reuniens (RE) of the midline thalamus, the medial (MDm) and central (MDc) divisions of the mediodorsal nucleus, the intermediodorsal nucleus, the central lateral, paracentral, and central medial nuclei of the rostral intralaminar complex and the submedial nucleus (SM). With some exceptions, medial divisions of the ORB (MO, VO) mainly targeted “limbic-associated” nuclei such as PT, RE, and MDm, whereas lateral division (VLO, LO, DLO) primarily distributed to “sensorimotor-associated” nuclei including MDc, SM, and the rostral intralaminar complex. As discussed herein, the medial/midline thalamus may represent an important link (or bridge) between the orbital cortex and the hippocampus and between the ORB and medial prefrontal cortex. In summary, the present results demonstrate that each division of the orbital cortex projects in a distinct manner to nuclei of the thalamus which suggests unique functions for each division of the orbital cortex.  相似文献   

20.
Single stimulations of the vagina and cervix were performed between proestrus and the first day of diestrus with a stimulator designed to grade the intravaginal penetration of a rod. The percent incidence of pseudopregnancy after this stimulation was exponentially related to the extent of intravaginal penetration and was also affected by the stage of the cycle at which the stimulation was performed. At 10.00 h on proestrus, an exponential increase in the incidence of pseudopregnancy was observed with shallow penetrations, while an exponential decrease was found when deeper penetrations were applied. Such negative exponential correlation had disappeared at 22.00 h on proestrus. At that time, also, some responses were elicited by very shallow penetrations (17 mm) and all the animals responded to penetrations of 20 mm or more. Sensitivity to cervicovaginal stimulation at 10.00 h on estrus was lower than that at 22.00 h on proestrus and it was even lower at 10.00 h on the first day of diestrus. The response to 18 mm of penetration was studied every 3 h between 10.00 h on proestrus and 10.00 h on estrus, and then every 12 h until 10.00 h on the first day of diestrus. This stimulation was usually ineffective to induce pseudopregnancy, except for a brief period encompassing the night between proestrus and estrus, when a peak in the incidence of responses was reached. This peak sensitivity could be advanced following the s.c. administration of 250 and 500 ng of LH-RH at 11.00 h on proestrus. Other doses were ineffective. The peptide (500 ng) was unable to induce pseudopregnancy in rats that received no cervicovaginal stimulation.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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