亚甲基四氢叶酸还原酶基因 C677T多态性与同型半胱氨酸水平的相关性

目的探究 985例云南地区人群亚甲基四氢叶酸还原酶( MTHFR)C677T基因多态性与同型半胱氨酸( Hcy)水平的相关性。方法选取 2018年 1月至 2019年 3月就诊于云南省第三人民医院并进行 MTHFR C677T基因检测的 985例汉族人群(包括住院病人 559例、体检人群 426例)作为研究对象,将所有研究对象按照基因型分为 CC、CT、TT三组。采用 PCR?芯片杂交法检测 MTHFR C677T基因型。结果男性 CC、CT、TT基因型分布频率与女性比较差异无统计学意义( P＞0.05)。三种基因型在不同年龄组中分布差异无统计学意义( P＞0.05)。 985例研究对象 Hcy检出最高浓度为 86.40 mmol/L,最低浓度为 5.00 mmol/L,均为 CT基因型。三种基因型 Hcy浓度为 13.50(5.55,21.45)mmol/L,其中 CC基因型 Hcy水平为 12.30(6.73,17.87) mmol/L,CT基因型 Hcy水平为 12.68(7.20,18.16)mmol/L,TT基因型 Hcy水平为 19.04(4.11,42.19)mmol/L,TT基因型 Hcy水平高于 CC和 CT,差异有统计学意义( P＜0.001)CC和 CT基因型的 Hcy水平差异无统计学意义( P＞0.05)。结论 985例云南地区人群 MTHFR C677T基因多态性与 Hcy水平具,有相关性, TT基因型可能为高 Hcy血症的危险因素。     

H-型高血压患者MTHFR基因型分布及与冠心病的关系

目的探讨H-型高血压患者中N5,N10-亚甲基四氢叶酸还原酶(MTHFR)C677T位点突变与血浆同型半胱氨酸(homocysteine,Hcy)及冠心病之间的关系。方法选择60例经冠状动脉造影的H-型高血压患者,分为冠心病组33例,非冠心病组27例,应用基因芯片技术检测2组MTHFR基因型,并比较2组MTHFR基因型分布及血浆Hcy水平。结果冠心病组的MTHFR基因CC型频率为27.3%,CT型频率为48.5%,TT型频率为24.2%。非冠心病组CC型频率为40.7%,CT型频率为48.2%,TT型频率为11.1%,冠心病组TT型基因及T等位基因频率高于非冠心病组,但是两组差异没有统计学意义(P>0.05)。冠心病组的血浆平均Hcy浓度(19.82±16.2)μmol/L高于非冠心病组(15.78±5.63)μmol/L(P=0.022<0.05),TT型的患者平均血浆Hcy浓度(32.58±23.06)μmol/L高于CC(14.64±6.93)μmol/L及CT(14.76±3.65)μmol/L组(P<0.05),差异有统计学意义。结论 MTHFR基因多态性与H-型高血压患者冠心病的发生无明显相关性,MTHFR基因突变导致高同型半胱氨酸血症。高同型半胱氨酸血症是冠心病的独立危险因素。     

桂西地区人群MTHFR基因多态性分布特征及其与高同型半胱氨酸血症的相关性

目的 探讨桂西地区人群亚甲基四氢叶酸还原酶(MTHFR)基因677C/T多态性分布特点，分析桂西地区和其他地区677C/T多态性分布差异，并进一步探讨677C/T多态性与高同型半胱氨酸(HHcy)和血清同型半胱氨酸(Hcy)水平是否存在关联。方法 选取2020年1月至2022年1月在百色市人民医院保健科进行体检并行MTHFR基因检测的2 339人作为研究对象。采用聚合酶链反应(PCR)-荧光探针法检测677C/T多态性，循环酶法检测血清Hcy。根据性别、地区特征比较677C/T多态性分布差异。另外，按照Hcy>15μmol/L为HHcy,将研究对象分为HHcy组和对照组，分析MTHFR 677C/T多态性与HHcy和血清Hcy水平的相关性。结果 桂西地区2 339名体检人群中，MTHFR基因677C/T位点CC、CT和TT基因型的频率分别为59.9%、34.2%和5.9%,C、T等位基因频率分别为77.0%和23.0%。不同性别间基因型频率和等位基因频率分布比较，差异无统计学意义(P>0.05)。桂西地区人群677C/T多态性分布与茂名地区人群比较，差异无统计学意义(P&g...     

同型半胱氨酸及其代谢酶基因多态性与脑梗死的关系

目的探讨亚甲基四氢叶酸还原酶(MTHFR)基因C677T、胱硫醚合成酶(CBS)基因T27796C、蛋氨酸合成酶(MS)基因A2756G 3种基因突变及血浆同型半胱氨酸(Hcy)水平与脑梗死的关系,进一步确定遗传因素对血浆Hcy水平的影响,以及遗传因素在脑梗死发病中的意义。方法选择年龄与性别基本匹配的脑梗死组62例,健康对照组30名。采用高效液相色谱法测定受检者血浆Hcy水平,并应用多聚酶链反应-限制性内切酶片段长度多态性技术(PCR-RFLP)检测基因表型。计量资料用x±s表示,比较采用t检验和方差分析。基因型和等位基因频率分布采用2χ检验。应用Logistic回归分析筛选脑梗死的危险因素。结果脑梗死组血浆Hcy水平明显高于健康对照组[(23±12)与(11±14)μmol/L,P<0.05],脑梗死组MTHFR基因TT纯合基因型和T等位基因频率(分别为56.5%,71.8%)均明显高于健康对照组(分别为16.7%,35.0%)。MTHFRC677T基因型和等位基因频率分布差异有统计学意义(P<0.05)。MTHFR基因C677T纯合子基因型血浆Hcy水平显著高于野生型[(21±11)与(14±3)μmol/L,P<0.01]。CBS T27796C基因型和等位基因频率分布差异无统计学意义(P>0.05),但CBS基因T27796C纯合子基因型血浆Hcy水平显著高于杂合子基因型[(23±11)与(15±6)μmol/L,P<0.01],又高于野生型[(23±11)与(15±5)μmol/L,P<0.01]。MS A2756G基因型和等位基因频率分布组间差异无统计学意义,血浆Hcy水平组间差异无统计学意义。Logistic回归分析显示脑梗死的危险因素为血浆Hcy水平和MTHFR C677T纯合子基因型。结论血浆Hcy水平与脑梗死的发生有一定联系。MTHFR基因C677T位点纯合子突变、CBS基因T27796C位点纯合子突变可引起血浆Hcy水平升高。MTHFR C677T纯合子突变致血浆Hcy水平增高,可能是引起脑梗死发病的重要遗传因素。     

同型半胱氨酸及其代谢酶MTHFR C677T基因多态性与广西壮族自治区玉林地区汉族冠心病患者的相关性

目的探讨血浆同型半胱氨酸(Hcy)及其代谢酶N5,10-亚甲基四氢叶酸还原酶(MTHFR)C677T基因多态性与广西壮族自治区玉林地区汉族冠心病的关系。方法纳入300例汉族人,经冠状动脉造影确诊的冠心病(CHD)组150例,非冠心病组作为对照组150例,抽取外周静脉血提取DNA,采用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)的方法检测2组MTHFR C677T基因型,同时用全自动生化分析仪检测Hcy及其他生化指标。结果 2组Hcy水平比较差异有统计学意义(P<0.05)。CC、CT、TT 3种基因型频率表达在CHD组和对照组中分别为18.7%、47.3%、34.0%和37.3%、42.0%、20.7%;CHD组中C和T等位基因为42.3%和57.7%,对照组中为58.3%和41.7%。2组3种基因型总体分布频率及等位基因频率分布差异均有统计学意义(P<0.05)。Hcy在CHD组中TT型高于CC型及CT型(P<0.05)。Logistic回归显示,年龄、血压、血脂水平可能为冠心病发病的危险因素。结论 Hcy升高及其代谢酶(MTHFR)C677T基因多态性可能与玉林地区汉族冠心病的发生有关。     

同型半胱氨酸及其代谢关键酶MTHFR C677T基因多态性与颅内动脉瘤的关系

目的 探讨同型半胱氨酸（Hcy）及其代谢关键酶N5,10-亚甲基四氢叶酸还原酶（MTHFR）C677T基因多态性与颅内动脉瘤的关系.方法 采用荧光偏振免疫法检测76例颅内动脉瘤患者和77例健康成人的血浆Hcy水平,并利用聚合酶链式反应技术检测其MTHFR C677T基因多态性.结果 颅内动脉瘤组血浆Hcy水平（16.14±6.72）μ mol/L高于对照组（11.20±3.20）μmol/L,两组间的差异有显著性（P〈0.05）.两组MTHFR C677T等位基因频率差异无显著性（P〉0.05）;颅内动脉瘤组MTHFR C677T CT基因型频率明显高于正常对照组（P〈0.01）,患颅内动脉瘤的风险是对照组的2.57倍.CC、CT基因型颅内动脉瘤组患者血浆Hcy水平明显高于对照组（P〈0.01）;颅内动脉瘤组患者CT基因型的血浆Hcy浓度较其它基因型高（P〈0.05）.结论 高Hcy血症与颅内动脉瘤病发生有一定关系,MTHFR CT基因型与颅内动脉瘤明显相关.     

MTHFR、MTRR基因多态性与妊娠期高血压病的关系

目的 探讨叶酸(FA)和同型半胱氨酸(Hcy)代谢过程关键酶亚甲基四氢叶酸还原酶(MTHFR)和甲硫氨酸合成酶还原酶(MTRR)基因多态性与妊娠期高血压病(HDCP)的关系。方法 采用PCR限制性内切酶多态性法检测HDCP患者104例(A组)和健康孕妇92例(C组)MTHFR基因C677T位点(MTHFR C677T)和MTRR基因A66G位点(MTRR A66G)基因多态性,采用循环酶法和微粒子化学发光法分别检测两组血清Hcy和FA水平,分析MTHFR C677T和MTRR A66G基因多态性与HDCP易感性的关系,比较A组不同基因分型血清Hcy和FA水平以及母婴结局。结果 A组MTHFR C677T基因TT基因型频率和T位点等位基因频率高于C组(P<0.05)。两组MTRR A66G基因不同基因型和等位基因频率相仿(P>0.05)。MTHFR C677T基因多态性与HDCP易感性有关,CT、TT基因型孕妇发生HDCP风险高(P<0.05)。A组MTHFR C677T基因CC、CT基因型血清Hcy水平降低,而血清FA水平升高(P<0.05)。A组MTHFR C...     

MTHFR基因多态性与冠心病的关系

目的研究天津地区人群N5,N10-亚甲基四氢叶酸还原酶(MTHFR)基因C 677 T多态性与冠心病的关系.方法应用聚合酶链反应(PCR)技术和限制性酶切片段长度多态性(RFLP)分析技术检测50例冠心病患者(冠心病组)和50例正常人(对照组)MTHFR基因C 677 T多态性,应用高效液相色谱法测定血浆同型半胱氨酸(Hcy)水平,采用125Ⅰ标记放免法测定血清叶酸浓度.结果(1)冠心病组与对照组MTHFR基因频率分布不同(P＜0 05),对照组CC型、TC型、TT型基因频率分别为52.0%,28.0%,20.0%;冠心病组分别为26.0%,44.0%,30.0%.冠心病组T等位基因频率为52.0%,C等位基因频率为48.0%,与对照组比较有显著性差异(P＜0.05).(2)两组的TT基因型者血浆Hcy浓度均明显高于CC和TC基因型者(P＜0.05),而后两者间无显著性差异(P＞0.05).(3)冠心病组Hcy浓度高于对照组(P＜0.05).两组叶酸水平无显著性差异(P＞0.05),血浆Hcy浓度与叶酸水平均呈显著负相关(r分别为-0.617和-0.588,P＜0.05).结论MTHFR基因C 677 T点突变与冠心病发病密切相关,MTHFR基因纯合突变是引起高Hcy血症的一个重要的遗传因素.     

口服还原型谷胱甘肽治疗不同基因型高同型半胱氨酸血症的临床观察

目的观察口服还原型谷胱甘肽(glutathione,GSH)对亚甲基四氢叶酸还原酶(methylenetetrahydrofolate reductase,MTHFR)不同基因型高同型半胱氨酸血症(hyperhomocysteinemia,HHcy)的治疗效果。方法 107例HHcy患者被分为G组(55例,口服GSH 0.2 g bid)和F组(52例,口服叶酸片0.4 mg bid)。所有患者抽取外周血提取DNA,通过聚合酶链反应-芯片杂交法进行MTHFRC677T位点的基因分型(CC型、CT型和TT型)。12个月后比较2组的总体平均血清同型半胱氨酸(homocysteine,Hcy)浓度,以及2组中MTHFR C677T位点不同基因型患者的平均Hcy浓度。结果 12个月后,G组、F组Hcy浓度均显著低于治疗前(P<0.01),G组与F组比较差异无统计学意义;在不同基因型患者,G组、F组Hcy浓度均低于治疗前;但在CC型患者,G组Hcy浓度降低较F组更明显(10.3±3.2μmol·L^-1vs15.5±3.6μmol·L^-1,P<0.01);在CT型患者,2组治疗后Hcy浓度差异无统计学意义;而在TT型患者,F组Hcy浓度降低较G组更明显(26.7±9.8μmol·L^-1vs45.5±10.6μmol·L^-1,P<0.01)。结论 GSH能有效降低Hcy,总体降低Hcy浓度效应与叶酸相近。但在MTHFR C677T CC型及TT型HHcy患者中,GSH与叶酸降低Hcy的作用有差异。GSH可作为治疗HHcy药物之一,尤其对MTHFR C677T CC型HHcy患者,建议优先推荐应用。     

湘潭市汉族女性MTHFR和MTRR基因多态性分布及其与血浆Hcy水平的关系

目的 分析湖南省湘潭市女性5,10-亚甲基四氢叶酸还原酶(MTHFR)C677T、A1298C及甲硫氨酸合成酶还原酶(MTRR)A66G位点基因多态性的分布特征,并分析其多态性与血浆同型半胱氨酸(Hcy)水平的关系。方法以湘潭市1 701例女性为研究对象,检测其MTHFR C677T、A1298C和MTRR A66G位点基因多态性,并对其中110例孕期女性检测其血浆Hcy水平。统计分析本地区基因多态性的分布特征,并与淄博、郑州、烟台、镇江、松滋、惠州、琼海等地区进行比较;分析多态性与血浆Hcy水平的关系。结果 湘潭市女性的MTHFR C677T位点TT纯合突变基因型频率为12.6%,高于惠州(10.9%)、琼海(6.1%),低于淄博(43.6%)、郑州(36.8%)、烟台(32.2%)、镇江(21.8%),差异均有统计学意义。与松滋相比差异无统计学意义。MTHFR A1298C位点CC纯合突变基因型频率为4.8%,低于琼海(7.1%)、高于淄博(1.4%)、郑州(2.4%)、烟台(1.8%)、镇江(3.5%)、松滋(2.6%),差异均有统计学意义。MTRR A66G位点GG纯合突变基因型频率为6.8%,高于淄博(4.8%),低于琼海(9.3%),差异有统计学意义。血浆Hcy浓度与MTHFR C677T位点基因型多态性有关,TT型人群Hcy浓度高于CT型人群和CC型人群(μmol/L:8.52±2.01 vs 5.94±1.47 vs 5.71±0.18);血浆Hcy浓度与MTHFR A1298C位点基因型多态性有关,CC型人群Hcy浓度高于AA型人群和AC型人群(μmol/L:9.83±2.26 vs 6.35±2.13 vs 5.55±1.75);血浆Hcy浓度与MTRR A66G位点基因型无关。结论 湘潭市女性MTHFR和MTRR基因多态性频率不同于其他地区,具有地域特异性。MTHFR C677T、A1298C位点多态性与Hcy水平有关。     

Quantitative in vivo and in vitro sex differences in artemisinin metabolism in rat

1. The pharmacokinetics of the antimalarial compound artemisinin were compared in the male and female Sprague-Dawley rat after single dose i.v. (20 mg.kg) or i.p. (50 mg.kg) administration of an emulsion formulation. 2. Plasma clearance of artemisinin was 12.0 (95% confidence interval: 10.4, 13.0) l.h. kg in the male rat and 10.6 (95% CI: 7.5, 15.0) l.h. kg in the female rat suggesting high hepatic extraction in combination with erythrocyte uptake or clearance. Artemisinin half-life was 0.5 h after both routes of administration in both sexes. Values for plasma clearance and half-lives did not statistically differ between the sexes. 3. After i.p. administration artemisinin AUCs were 2-fold higher in the female compared with male rat (p 0.001). Artemisinin disappearance was 3.9-fold greater in microsomes from male compared with female livers and it was inhibited in male microsomes by goat or rabbit serum containing antibodies against CYP2C11 and CYP3A2 but not CYP2B1 or CYP2E1. 4. The unbound fraction of artemisinin in plasma was lower (p 0.001) in plasma obtained from the male (8.8 2.0%) compared with the female rat (11.7 2.2%). 5. The possibility of a marked sex difference, dependent on the route of administration, has to be taken into account in the design and interpretation of toxicological studies of artemisinin in this species.     

Quantitative in vivo and in vitro sex differences in artemisinin metabolism in rat

1. The pharmacokinetics of the antimalarial compound artemisinin were compared in the male and female Sprague-Dawley rat after single dose i.v. (20 mg x kg(-1)) or i.p. (50 mg x kg(-1)) administration of an emulsion formulation. 2. Plasma clearance of artemisinin was 12.0 (95% confidence interval: 10.4, 13.0) 1 x h(-1) x kg(-1) in the male rat and 10.6 (95% CI: 7.5, 15.0) 1 x h(-1) x kg(-1) in the female rat suggesting high hepatic extraction in combination with erythrocyte uptake or clearance. Artemisinin half-life was approximately 0.5 h after both routes of administration in both sexes. Values for plasma clearance and half-lives did not statistically differ between the sexes. 3. After i.p. administration artemisinin AUCs were 2-fold higher in the female compared with male rat (p < 0.001). Artemisinin disappearance was 3.9-fold greater in microsomes from male compared with female livers and it was inhibited in male microsomes by goat or rabbit serum containing antibodies against CYP2C11 and CYP3A2 but not CYP2B1 or CYP2E1. 4. The unbound fraction of artemisinin in plasma was lower (p < 0.001) in plasma obtained from the male (8.8 +/- 2.0%) compared with the female rat (11.7 +/- 2.2%). 5. The possibility of a marked sex difference, dependent on the route of administration, has to be taken into account in the design and interpretation of toxicological studies of artemisinin in this species.     

Interindividual variability in metabolic activation in humans in vivo

In assessing interindividual variability in metabolic activation, the toxic metabolite is often too unstable for conventional analysis. Possible alternatives include a stable product of the reactive metabolite e.g. cysteinyl derivatives of N-acetyl-4-benzoquinoneimine, the toxic metabolite of paracetamol, adducts with DNA or protein, and indirect measurement of the activity of the enzyme(s) producing the active metabolite. An example of the last approach is the use of furafylline, a highly specific inhibitor of human CYP1A2, to determine the extent of the metabolic activation of the cooked food mutagens PhIP and MeIQx. The extent of inhibition, determined from levels of unchanged amine in urine, is an indirect measure of the activity of the activation pathway. Further refinement of this approach, allied to improved measures of the biological process of interest should prove of value in evaluating interindividual variability and its role in the risk assessment process.     

Theophylline kinetics in peripheral tissues in vivo in humans

Several biochemical and cellular effects have been described for methylxanthines under in vitro conditions. However, it is unknown, whether threshold concentrations required to exert these effects are attained in target tissues in vivo. We therefore employed the microdialysis technique for measuring theophylline concentrations in peripheral tissues under in vivo conditions.Following in vitro and in vivo calibration, microdialysis probes were inserted into the medial vastus muscle and into the periumbilical subcutaneous adipose layer of healthy volunteers. Following single oral dose administration of 300 mg or i.v. infusion of 240 mg theophylline, in vivo time courses of theophylline concentrations were monitored in tissues and plasma. Major pharmacokinetic parameters (c_max, t_max, AUC) were calculated for plasma and tissue time courses. The mean AUC_tissue /AUC_plasma-ratio was 0.56 (p.o.) and 0.55 (i.v.) for muscle and 0.55 (p.o.) and 0.72 (i.v.) for subcutaneous adipose tissue.We conclude that microdialysis provides important information on the distribution and the tissue pharmacokinetics of theophylline.Abbreviations FPIA Fluorescence polarisation immuno assay - AUC Area under the curve - t_max Time to peak concentration - c_max Peak concentration     

休克时血中氧自由基的变化

本实验测定10名休克患者血浆和红细胞的丙二醛(MDA)、血浆总抗的氧化活性(AOA)的含量。结果表明:休克病人红细胞膜和血浆 MDA 含量(4.298±0.722;5.348±0.834)与对照组(3.235±0.682;4.356±1.081)比较明显增高(P<0.05);血浆 AOA(39.65±7.858)与对照组(48.21±10.81)比较明显降低(P<0.01)。提示:休克时,患者机体内自由基反应增强是引起组织细胞损伤的原因之一。     

Changes in angiopoietin expression in glomeruli involved in glomerulosclerosis in rats with daunorubicin-induced nephrosis

AIM: To study the potential pathological role of endogenous angiopoietins in daunorubicin-induced progressive glomerulosclerosis in rats. METHODS: Seventy male Wistar rats were allocated randomly into a daunorubicin group (DRB; n=40) or a control group (n=30). The rats in the DRB group were injected with DRB (15 mg/kg), in their tails. Subsequently, at intervals of 1, 2, 4, 6, 8, and 12 weeks, 5 male Wistar rats in each group were chosen randomly for 24 h urinary protein quantitative measurements (24 h UPQM), and determination of plasma tumor necrosis factor alpha (TNF-alpha), angiopoietin-1 (Ang1), and angiopoietin-2 (Ang2) levels. Kidney sections were examined by electron microscopy, Periodic Acid Schiff (PAS) staining, immunohistochemical staining and in situ hybridization histochemistry. RESULTS: As glomerulosclerosis progressed in the DRB group, expression of Ang1 mRNA and protein in glomeruli decreased and expression of TNF-alpha protein, Ang2 mRNA and protein in glomeruli increased. Expression of Ang1 mRNA and protein in glomeruli were negatively correlated with 24 h UPQM, Fn protein expression, and mean area of extracellular matrix (MAECM). In comparison, expression of Ang2 mRNA and protein in glomeruli were positively correlated with 24 h UPQM, Fn protein expression and MAECM; furthermore, there was a positive correlation between plasma Ang2 and 24 h UPQM. Plasma TNF-alpha and expression of TNF-alpha in glomeruli were positively correlated with expression of Ang2 mRNA and protein in glomeruli. There was a negative correlation between Ang1 protein expression and Ang2 protein expression in glomeruli. CONCLUSION: During DRB-induced glomerulosclerosis, podocyte injury led to a shift in the balance of Ang1 and Ang2 in glomeruli. Increased TNF-alpha in plasma and glomeruli may upregulate Ang2 expression in glomeruli. Elevated Ang2 in both plasma and glomeruli may mediate protein permeability through the glomerular filtration barrier. Moreover, local expression of Ang2 may facilitate the progress of glomerulosclerosis by upregulating a component expression of extracellular matrix.     

Deoxynivalenol in cereals in Russia

A survey of the occurrence of deoxynivalenol (DON) and zearalenone (ZEN) in wheat, rye, barley and maize harvested in 1989-2001 in several regions of Russia has been conducted. A total of 5652 samples of cereals were analysed for DON and ZEN by using TLC and normal-phase HPLC with UV-detector. DON was detected in 69% of 2166 samples from Krasnodar region which is considered to be the major Fusarium endemic region of Russia. The contamination levels ranged from 0.1 till 8.6 ppm, MTEL was exceeded in 37% of these samples. The positive correlation between DON concentration and a percentage of Fusaria-damaged wheat kernels has been shown. DON occurrence and contamination levels were much lower that for wheat. Based on the results of monitoring and the data of average actual consumption of wheat products in Russia, the estimated daily intake of DON per 1 kg of body weight (EDI)was calculated. EDI varied from 0.07 ug in 1990-1991 till 1.40 ug in 1992. Although average EDI were lower than adopted tolerable daily intake (TDI, 3 ug/kg body weight) EDIs for the North-Caucasian region in some cases exceeded TDI.