贵州六盘水市彝族与汉族女性叶酸代谢关键酶基因多态性特征分布

目的了解六盘水市彝族、汉族育龄女性叶酸代谢水平,为指导当地孕期叶酸补充提供一定的依据。方法选取2016—2017年期间进行孕期体检的育龄女性1 054例(汉族950例,彝族104例)为研究对象,采集口腔黏膜上皮脱落细胞提取基因组DNA,利用荧光定量PCR方法检测受检者5,10-亚甲基四氢叶酸还原酶(MTHFR)(C677T、A1298C)和甲硫氨酸合成酶还原酶(MTRR)(A66G)位点基因型与等位基因频率,并通过与西南地区已报道的其他少数民族进行比较,获得本地区彝族、汉族上述基因位点多态性分布特征。结果六盘水市彝族女性MTHFR C677T位点基因型和等位基因频率与当地汉族、思南苗族、思南土家族、大理白族比较均具有统计学差异,其中MTHFR 677CT,677TT基因型频率均低于其他民族。结论六盘水市彝族与汉族育龄女性叶酸代谢关键酶基因位点多态性特征有所区别,可以有针对性地制定符合当地民族特征的个性化叶酸补充方案。     

亚甲基四氢叶酸还原酶基因多态性在妇产科领域的研究进展

亚甲基四氢叶酸还原酶(MTHFR)是参与机体叶酸代谢和DNA甲基化的限速酶,参与体内多种生理生化反应。MTHFR基因突变有多种类型,C677T位点突变是研究最多、最常见的突变类型。该基因突变导致酶活性降低,进而影响叶酸代谢、DNA合成及甲基化过程,最终增加该基因相关疾病的易感性。由于MTHFR C677T基因多态性存在地域和种族差异,导致同一疾病在不同地区和种族中出现不同的研究结果。近年来随着基因多态性与相关疾病关注度增加,研究发现MTHFR C677T基因多态性可致高同型半胱氨酸血症,使胚胎发育障碍并损伤血管内皮细胞,导致复发性流产及妊娠期高血压疾病,而妇科肿瘤的发生可能主要与DNA甲基化受阻相关。现就MTHFR C677T基因多态性在妇产科领域的研究进展进行综述。     

亚甲基四氢叶酸还原酶基因C677T单核苷酸多态性与卵巢癌易感性的关系

目的:研究亚甲基四氢叶酸还原酶(MTHFR)基因第4外显子677位点单核苷酸多态性与卵巢癌易感性的关系。方法:采用聚合酶链反应-限制性片段长度多态性方法,检测81例卵巢癌患者和80例正常对照者的亚甲基四氢叶酸还原酶基因C677T位点突变。结果:卵巢癌组和对照组中MTHFR基因677等位基因位点C和T的分布差异有统计学意义(P<0.05),其中等位基因T使卵巢癌发病风险增加1.93倍。MTHFR基因677C/T各基因型分布差异有统计学意义(P<0.05),纯合突变(T/T)基因型、杂合突变(C/T)基因型与野生(C/C)基因型相比,患卵巢癌的危险度分别提高了3.48倍和2.15倍。结论:MTHFR基因677位点等位基因突变与卵巢癌发生有一定关系,突变基因型增加了卵巢癌的发病风险。     

亚甲基四氢叶酸还原酶基因C677T多态性与男性不育的相关性

目的:探讨亚甲基四氢叶酸还原酶(MTHFR)基因C677T多态性与中国东北人群男性不育的关系。方法:应用聚合酶链式反应-限制性片断长度多态性(PCR-RFLP)方法检测53例健康可育男性和182例不育男性的MTHFR基因C677T位点多态性。结果:弱精子症不育组(AS组)和不明原因不育组(UR组,精液常规正常)的3种基因型和T等位基因频率分别与对照组相比,差异均具有统计学意义(P<0.05)。结论:MTHFR基因C677T多态性可能与中国东北人群男性不育有相关性,且与弱精子症和不明原因不育的发生密切相关。     

淄博市汉族女性亚甲基四氢叶酸还原酶和甲硫氨酸合成酶还原酶基因多态性分布研究

目的:分析淄博市汉族女性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基因多态性的分布特征。方法:采用横断面调查研究方法,以淄博市1041例汉族女性为研究对象,采集口腔黏膜上皮细胞,提取基因组DNA,采用Taqman-MGB技术检测MTHFR和MTRR基因多态性。统计分析基因多态性的分布特征,并与已报道的其他地区数据进行比较。结果:淄博市汉族女性的MTHFR 677TT纯合突变基因型频率为43.6%,显著高于郑州、德阳、海南地区(P<0.01);MTHFR 1298CC纯合突变基因型频率为1.4%,显著低于德阳和海南地区(P<0.01)。MTRR 66GG纯合突变基因型频率为4.8%,显著低于海南地区(P<0.01)。结论:淄博市汉族女性有不同于其他地区的MTHFR和MTRR基因多态性分布特征。     

反复妊娠丢失患者的亚甲基四氢叶酸还原酶的多态性

目的检测反复妊娠丢失(recurrent pregnancy loss,RPL)妇女亚甲基四氢叶酸还原酶(methylenetetrahydrofolate reductase,MTHFR)的多态性。方法选择不明原因的反复妊娠丢失二次以上的妇女71例,正常对照93例,无妊娠丢失及血栓病史,除外口服避孕药妇女。MALDI-TOF质谱检测技术检测MTHFR的多态性C677T、A1298C、T1317C和G1793A。结果RPL妇女MTHFR C677T、G1793A的杂合子和纯合子的突变率均明显高于对照组,差异有显著性(P<0.05)。MTHFR的A1298C在RPL组和正常对照组无明显差别。T1317C在两组中均未发现。RPL组连锁基因频率677CT/1793GA明显高于正常对照组(RR=4.92)。结论RPL与MTHFR多态性密切相关,MTHFR C677T、G1793A突变是RPL的危险因素。其连锁基因突变可使妊娠丢失的发生率增加4.92倍。     

亚甲基四氢叶酸还原酶基因多态性与妊娠相关疾病

探讨亚甲基四氢叶酸还原酶基因多态性,特别是677 C→T突变与妊娠高血压综合征(PIH)、习惯性流产、胎盘血管疾病等妊娠相关疾病的关系.近年许多研究表明,亚甲基四氢叶酸还原酶(MTHFR)基因677 C→T突变可导致MTHFR活性下降、血浆同型半胱氨酸增高,是多种妊娠相关疾病的高危遗传因素,补充叶酸可减少妊娠并发症的风险,就近年相关研究综述.     

亚甲基四氢叶酸还原酶基因多态性与妊娠相关疾病

探讨亚甲基四氢叶酸还原酶基因多态性，特别是677C→T突变与妊娠高血压综合征(PIH)、习惯性流产、胎盘血管疾病等妊娠相关疾病的关系。近年许多研究表明，亚甲基四氢叶酸还原酶(MTHFR)基因677C→T突变可导致MTHFR活性下降、血浆同型半胱氨酸增高，是多种妊娠相关疾病的高危遗传因素，补充叶酸可减少妊娠并发症的风险，就近年相关研究综述。     

思南县女性5,10-亚甲基四氢叶酸还原酶基因多态性调查及其与血清同型半胱氨酸水平相关性的研究

目的:研究叶酸代谢障碍关键酶基因5,10-亚甲基四氢叶酸还原酶(MTHFR)C677T、A1298C位点基因多态性与血清同型半胱氨酸(HCY)的相关性。方法:随机以贵州省思南县2 188例女性为研究对象,检测其MTHFR C677T、A1298C基因位点多态性,采用统计学方法分析该地区基因的多态性分布特征,并与其他同等级区域人群既有数据比对分析;对其中276例孕期女性,测定血清HCY浓度,分析该指标与遗传因素的相关性。结果:本县的汉族、苗族、土家族女性MTHFR C677T、A1298C位点基因型及等位基因分布情况差异无统计学意义(P0.05)。本地区汉族女性MTHFR 677TT基因型频率(14.9%)显著低于尚志、三河、寿光、张家港等地人群(P0.05),显著高于陵水县人群(P0.05);与郫县人群数据差异无统计学意义(P0.05)。MTHFR 1298CC基因型频率(4.2%)与郫县人群无统计学差异(P0.05),与其他各地区人群均有统计学差异(P0.05)。血清HCY水平在C677T位点3种基因型间有统计学差异(P0.05),而A1298C位点3种基因型间无统计学差异(P0.05)。结论:本县汉族女性MTHFR基因C677T、A1298C位点多态性分布特征有其自身的特点;C677T位点的多态性变化对血清HCY水平有显著影响。     

柳州市壮族与汉族女性5,10-亚甲基四氢叶酸还原酶、甲硫氨酸合成酶还原酶基因型和等位基因频率的分布

目的:调查柳州市壮族与汉族女性中5,10-亚甲基四氢叶酸还原酶(MTHFR)及甲硫氨酸合成酶还原酶(MTRR)基因的单核苷酸多态性分布特征。方法:通过横断面调查研究方法,以广西省柳州市372位壮族和478位汉族女性为研究对象,检测其MTHFR C677T、A1298C和MTRR A66G基因位点多态性,统计分析该地区基因多态性的分布特征,并与已报道的其他地区少数民族女性数据进行比较。结果:该地区壮族和汉族女性比较,MTHFR C677T的基因型频率差异在两者间有统计学意义(P0.05),而MTHFR A1298C和MTRR A66G两者间无统计学差异(P0.05);MTHFR C677T和A1298C的等位基因频率在两民族间的差异有统计学意义(P0.05),而MTRR A66G则无统计学差异(P0.05)。该地区壮族女性MTHFR C677T的基因型频率和等位基因分布与延边朝鲜族、新疆维吾尔族、银川回族、思南苗族、思南土家族、柳州苗族、三亚黎族间差异均有统计学意义(P0.05);而该地区壮族女性MTHFR A1298C的基因型频率和等位基因分布与延边朝鲜族、银川回族、思南苗族、思南土家族间亦有统计学差异(P0.05);MTRR A66G的分布上则与新疆维吾尔族、思南苗族、思南土家族、南宁壮族、三亚黎族有统计学差异(P0.05)。结论:广西省柳州市壮族女性的MTHFR和MTRR基因多态性分布特征与该地区汉族女性不同,与其他地区少数民族也不相同。     

Outcomes in the absence of the ductus venosus diagnosed in the first trimester

Purpose: To clarify the outcomes of the absence of the ductus venosus (DV) diagnosed in fetuses suspected to have a structural abnormality during a morphological assessment in the first trimester.

Methods: Infants in whom ultrasound fetal morphological assessments were attempted in the first trimester (11 to 13–6 weeks of gestation) and who were subsequently delivered between 2013 and 2015 at Showa University Hospital were enrolled. In cases in which the absence of the DV was diagnosed in the first trimester, the prognosis was assessed.

Results: First-trimester ultrasound screening was performed in a total of 2610 cases between 2013 and 2015. Fetal edema (n?=?38), hydrops (n?=?16), abnormal four-chamber view findings (n?=?2), and tricuspid regurgitation (n?=?1) were observed in a total of 52 cases (2.0%). In 4 of the 52 cases with abnormal ultrasound findings, the absence of the DV was detected.

Conclusion: If fetal edema or hydrops in early pregnancy is found without any other structural abnormalities, not only chromosomal abnormalities should be suspected but also an evaluation for the absence of the DV should be included. In addition, absence of the DV with fetal edema may be associated with the outcomes of cardiac dysfunction, chromosome abnormalities, and intrauterine sudden death. Severe fetal edema is associated with a poor prognosis, and the family must be carefully informed of the potential outcomes.     

Challenges in the Practice of Sexual Medicine in the Time of COVID-19 in the United Kingdom

BackgroundOn 23rd March 2020, the UK government released self-isolation/social distancing guidance to reduce the risk of transmission of SARS-CoV-2. The influence such guidance has on sexual activity is not known.AimTo investigate levels and correlates of sexual activity during COVID-19 self-isolation/social distancing in a sample of the UK public.MethodsThis paper presents preplanned interim analyses of data from a cross-sectional epidemiological study, administered through an online survey.OutcomesSexual activity was measured using the following question: “On average after self-isolating how many times have you engaged in sexual activity weekly?” Demographic and clinical data were collected, including sex, age, marital status, employment, annual household income, region, current smoking status, current alcohol consumption, number of chronic physical conditions, number of chronic psychiatric conditions, any physical symptom experienced during self-isolation, and number of days of self-isolation/social distancing. The association between several factors (independent variables) and sexual activity (dependent variable) was studied using a multivariable logistic regression model.Results868 individuals were included in this study. There were 63.1% of women, and 21.8% of adults who were aged between 25 and 34 years. During self-isolation/social distancing, 39.9% of the population reported engaging in sexual activity at least once per week. Variables significantly associated with sexual activity (dependent variable) were being male, a younger age, being married or in a domestic partnership, consuming alcohol, and a higher number of days of self-isolation/social distancing.Clinical ImplicationsIn this sample of 868 UK adults self-isolating owing to the COVID-19 pandemic, the prevalence of sexual activity was lower than 40%. Those reporting particularly low levels of sexual activity included females, older adults, those not married, and those who abstain from alcohol consumption.Strength and LimitationsThis is the first study to investigate sexual activity during the UK COVID-19 self-isolation/social distancing. Participants were asked to self-report their sexual activity potentially introducing self-reporting bias into the findings. Second, analyses were cross-sectional and thus it is not possible to determine trajectories of sexual activity during the current pandemic.ConclusionInterventions to promote health and well-being during the COVID-19 pandemic should consider positive sexual health messages in mitigating the detrimental health consequences in relation to self-isolation/social distancing and should target those with the lowest levels of sexual activity.Jacob L, Smith L, Butler L, et al. Challenges in the Practice of Sexual Medicine in the Time of COVID-19 in the United Kingdom. J Sex Med 2020;17:1229–1236.     

Carcinoma in situ of the cervix in the postmenopausal female

Eleven cases of postmenopausal carcinoma in situ of the cervix (CIS) are reviewed. They comprised 7% of the 178 cases of CIS evaluated and treated at The Johns Hopkins Hospital between January 1, 1977 and June 30, 1980. The extensive involvement of the endocervical canal in the postmenopausal patient requires conization in addition to colposcopy and endocervical curettage in order to fully evaluate the cervical disease.     

Weaknesses in the case against prepatterning in the mouse

Serious weaknesses are exposed regarding recent claims to have demonstrated that there is no prepatterning of axes in the mouse. That the orientation of the axis of polarity of the blastocyst is dictated by the shape of the zona pellucida is contradicted by systematic observations on living conceptuses. Moreover, this 'mechanical constraint' hypothesis fails to account for key findings on which the case for prepatterning is based.     

Cyclosporine in transplantation of the liver in the dog

Orthotopic hepatic transplantation was performed upon 29 dogs. Four dogs received no immunosuppressant, 12 received cyclosporine and 13 received azathioprine. Dogs treated with cyclosporine at a dose of 20 milligrams per kilogram yielded histologic and functional data indistinguishable from those of the dogs in the sham transplant group. Histologic evidence of rejection consistently appeared when the dose was decreased to 10 milligrams per kilogram but was reversed upon resuming the administration of the higher dosage. Serum levels of bilirubin and hepatic enzymes, serum glutamic-oxalacetic transaminase, serum glutamic-pyruvic transaminase and alkaline phosphatase did not correlate with the development or resolution of histologic evidence of rejection in dogs receiving cyclosporine. Dogs receiving cyclosporine for 60 days had a prolonged survival when the drug was stopped, whereas the dogs receiving such therapy for less than 60 days did not have a prolonged survival period.     

Variations in the distribution of glycosaminoglycans in the uterine cervix of the pregnant woman

A study was made of the modifications of glycosaminoglycans in the uterine cervix and the relationship to gestation. These substances are essential constituents of connective tissue, and a modification of their concentration could affect the physical and chemical characteristics of the cervix.Glycosaminoglycans were extracted from cervical biopsies obtained from pregnant and non-pregnant women. This study showed dermatan sulfate to be quantitatively the most important glycosaminoglycan in the cervix of both the groups studied, and that a significant decrease in the concentration of both dermatan sulfate and chondroitin sulfates occurred in the biopsies obtained just after delivery. This was related to a decrease of collagen in the cervix at the end of gestation, as the proteoglycans containing dermatan sulfate are principally associated with collagen.