A follow-up study on chromosomal aberrations in lymphocytes of alcoholics during early, medium, and long-term abstinence

The frequencies of structural chromosomal aberrations were analyzed in peripheral blood lymphocytes of 31 chronic alcoholics at the beginning of an intensive outpatient treatment program at a neuropsychiatric clinic and were compared with 31 controls matched for gender, age, smoking habits, and nondrinkers. A statistically significant difference was observed in the level of chromosomal aberrations in somatic cells from alcoholics when compared with controls (3.01% vs. 1.28%, p < or = 0.001). A follow-up study was carried out for a subset of the patients after 3 months (8 subjects) and 12 months (14 subjects) of controlled abstinence. A statistically significant increase in the mean frequency of cells with aberrations was observed in the group of 14 subjects reinvestigated after 12 months of abstinence when compared with the mean value of the first blood samples immediately after hospitalization (4.61% vs. 3.01%; p < or = 0.001). An excessive increase in cigarette consumption during alcohol abstinence, reflected by a dramatic elevation of CO-hemoglobin levels, may, at least in part, account for this finding. In conclusion, chronic alcoholism leads to genotoxic effects that, instead of recovering after 1 year of alcohol abstinence, are even enhanced, most likely due to the "shift in addictive behavior."     

低中度近视EPI- LASIK术后视觉质量探讨

目的：：综合评价低中度近视机械法激光上皮下角膜磨镶术( EPI-LASIK)后视觉质量。方法：将行EPI-LASIK 术的60例120眼按等效屈光度( SE)分为两组：低度近视组(60眼),中度近视组(60眼)。测量术前和术后1 wk;1,6 mo的客观视力、像差、对比敏感度和眩光敏感度并进行比较。结果：术后两组裸眼视力( UCVA )均优于术前最佳矫正视力(UCVA)(P<0.05);两组术后6mo 总高阶像差值RMS比较有统计学差异( P<0.05)。两组术前及术后6mo高阶像差值比较均有统计学差异(P<0.05);术后1wk;1mo两组在五个频率上均有统计学差异(P<0.05);术后6 mo低度近视组恢复至术前水平,中度近视组在高频区(18.0c/d)和术前有统计学差异(P<0.05);术后1wk两组在3.0,6.0,12.0,18.0c/d频率上差异均有统计学差异(均P<0.05),术后1mo两组在12.0,18.0c/d频率上有统计学差异(均P<0.05),术后6mo两组均恢复至术前水平,比较均无明显差异。结论：低中度近视 EPI-LASEK 术后早期的视觉质量较差,中晚期有较好的视觉质量。     

High order aberration and straylight evaluation after cataract surgery with implantation of an aspheric, aberration correcting monofocal intraocular lens

AIM:To evaluate the quality of vision in respect to high order aberrations and straylight perception after implantation of an aspheric, aberration correcting, monofocal intraocular lens (IOL).METHODS:Twenty-one patients (34 eyes) aged 50 to 83y underwent cataract surgery with implantation of an aspheric, aberration correcting IOL (Tecnis ZCB00, Abbott Medical Optics). Three months after surgery they were examined for uncorrected (UDVA) and corrected distance visual acuity (CDVA), contrast sensitivity (CS) under photopic and mesopic conditions with and without glare source, ocular high order aberrations (HOA, Zywave II) and retinal straylight (C-Quant).RESULTS:Postoperatively, patients achieved a postoperative CDVA of 0.0 logMAR or better in 97.1% of eyes. Mean values of high order abberations were +0.02±0.27 (primary coma components) and -0.04±0.16 (spherical aberration term). Straylight values of the C-Quant were 1.35±0.44 log which is within normal range of age matched phakic patients. The CS measurements under mesopic and photopic conditions in combination with and without glare did not show any statistical significance in the patient group observed (P≥0.28).CONCLUSION:The implantation of an aspherical aberration correcting monofocal IOL after cataract surgery resulted in very low residual higher order aberration (HOA) and normal straylight.     

无创性产前基因测序技术在染色体非整倍体中的应用

目的探讨高通量并行测序技术在胎儿染色体非整倍体检测中的应用价值。方法2012年10月至2013年4月,生化血清学筛查唐氏高危或高龄孕妇,采用高通量测序技术对胎儿染色体非整倍体进行无创性产前检测,评估患病风险率,提示高危孕妇进行核型分析确诊。结果813例无创检测高危孕妇,13例提示异常高危,异常率为1．59％,其中4例21三体,3例18三体,6例性染色体。核型确诊4例均为21三体,准确度100％;2例18三体;1例47,XXY和1例47,XXX。结论基于高通量测序技术的方法能快速、准确、无创检测唐氏综合征,相对18三体和性染色体检测准确度和稳定性有待优化与提高。     

超声软指标在胎儿染色体异常筛查中的应用

目的：探讨各项超声软指标对胎儿染色体异常的筛查价值。方法：回顾性分析513例孕11-28周超声软指标阳性并行染色体核型分析的孕妇资料,分析各项软指标与胎儿染色体异常之间的关系,探讨联合指标对染色体异常的筛查价值。结果：513例胎儿中染色体异常91例,其中两项及两项以上超声软指标阳性胎儿染色体异常发生率（28.57%,16/56）明显高于单项超声软指标阳性胎儿（75/457,16.41%）,差异有统计学意义（P＜0.05）。颈项透明层（NT）增厚、鼻骨发育不良、单脐动脉阳性预测染色体异常的敏感性分别为46.15%、20.88%、17.58%,特异性分别为86.49%、90.75%、88.15%,此三项软指标筛查价值明显高于其他软指标,ROC曲线下面积（AUC）分别为0.66、0.56、0.53,三项指标联合的AUC为0.75,差异均有统计学意义（P＜0.05）。结论：超声软指标在染色体异常筛查中具有重要价值,其中NT增厚、鼻骨发育不良、单脐动脉阳性的胎儿染色体异常率较高,多项超声软指标阳性胎儿染色体异常风险明显增加,联合预测可提高诊断效能,建议行介入性产前诊断,降低新生儿出生缺陷。     

MreBCD-associated Cytoskeleton is Required for Proper Segregation of the Chromosomal Terminus during the Division Cycle of Escherichia Coli

Background:

In prokaryotic organisms, the mechanism responsible for the accurate partition of newly replicated chromosomes into daughter cells is incompletely understood. Segregation of the replication terminus of the circular prokaryotic chromosome poses special problems that have not previously been addressed. The aim of this study was to investigate the roles of several protein components (MreB, MreC, and MreD) of the prokaryotic cytoskeleton for the faithful transmission of the chromosomal terminus into daughter cells.

Methods:

Strain LQ1 (mreB::cat), LQ2 (mreC::cat), and LQ3 (mreD::cat) were constructed using the Red recombination system. LQ11/pLAU53, LQ12/pLAU53, LQ13/pLAU53, LQ14/pLAU53, and LQ15/pLAU53 strains were generated by P1transduction of (tetO)₂₄₀-Gm and (lacO)₂₄₀-Km cassettes from strains IL2 and IL29. Fluorescence microscopy was performed to observe localization pattern of fluorescently-labeled origin and terminus foci in wild-type and mutant cells. SOS induction was monitored as gfp fluorescence from PsulA-gfp in log phase cells grown in Luria-Bertani medium at 37°C by measurement of emission at 525 nm with excitation at 470 nm in a microplate fluorescence reader.

Results:

Mutational deletion of the mreB, mreC, or mreD genes was associated with selective loss of the terminus region in approximately 40% of the cells within growing cultures. This was accompanied by significant induction of the SOS DNA damage response, suggesting that deletion of terminus sequences may have occurred by chromosomal cleavage, presumably caused by ingrowth of the division septum prior to segregation of the replicated terminal.

Conclusions:

These results imply a role for the MreBCD cytoskeleton in the resolution of the final products of terminus replication and/or in the specific movement of newly replicated termini away from midcell prior to completion of septal ingrowth. This would identify a previously unrecognized stage in the overall process of chromosome segregation.     

36例X染色体异常的遗传学分析

目的通过对36例女性性发育异常患者的核型分析,进一步探讨X染色体异常的遗传学效应。方法采用外周血淋巴细胞培养制片、染色体G显带技术进行核型分析。结果36例性发育异常患者中X染色体数目异常26例,结构异常10例。结论女性X染色体异常可导致性腺发育不全,身材矮小,原发闭经,月经紊乱等,两条完整的X染色体对女性性腺及体征的发育是十分重要的。     

产前超声诊断胎儿先天性心脏病中染色体核型异常的分析

目的调查分析产前超声筛查后确诊先天性心脏病胎儿中染色体异常的分布,探讨先天性心脏病的病因,提高产前诊断率。方法对2011年1月至2013年6月在本院产前诊断中心产科门诊B超诊断的先天性心脏病胎儿进行羊水或脐带血的染色体核型检查,并综合分析先天性心脏病畸形分类和染色体异常的关系。结果确诊的70例先天性心脏病病例中,伴染色体异常者18例,占25.71%（18/70）,其中21-三体7例,18-三体7例,13-三体2例,X单体2例。先天性心脏病合并心外畸形的胎儿22例,其中有14例（63.64%）染色体检查发现异常,仅有先天性心脏病的胎儿核型分析发现4例染色体异常,占单纯先天性心脏病的8.33%（4/48）。CHD胎儿中,100%的13-三体、85.71%的18-三体、71.43%的21-三体和50%的X单体均不同程度的伴有心外器官的畸形。结论染色体异常是产前B超诊断的先天性心脏病,尤其是复杂型先天性心脏病或有合并其他心外畸形的主要病因。对于B超筛查出的复杂型先天性心脏病或有合并其他心外畸形的胎儿,应重视其染色体的检查。