山白树微卫星特征分析及分子标记开发

目的:山白树是中国特有珍稀濒危植物。分析微卫星特征,开发其微卫星分子标记。方法:采用Illumina二代测序技术建立山白树基因组文库和微卫星文库,分析微卫星组成类型,设计山白树引物,用5个山白树种群进行扩增和检测以分析其多态性。结果:二代测序共返回38,942,660条100 bp配对序列,通过质量修剪及拼接得到200,386条拼接序列,其中长度 335 bp的为7 614条;在7 614条序列中检测出微卫星位点694个,其中单核苷酸重复最多,单核苷酸重复中A/T重复数量最多;二核苷酸长度变异最大,其中AG/CT重复数量最多,重复长度变异情况与微卫星丰度呈正相关。为36条山白树微卫星重复次数高的序列设计引物,经聚合酶链式反应(PCR)扩增和聚丙烯酰胺凝胶电泳检测,20对引物多态性丰富且条带清晰,等位基因数(NA)在3~6之间,平均为4,多态性信息含量(PIC) 0. 535 5~0. 754 0,平均值0. 615 5。对5个山白树种群的群体遗传分析发现,该物种遗传多样性较高(h=0. 697 5,I=1. 436 8,HE=0. 702 2),种群遗传分化显著(Fst=0. 374)。结论:通过部分山白树的群体遗传也可以说明本次开发的引物可用性较好。该研究开发了山白树微卫星分子标记引物,为山白树分子遗传学奠定了基础。     

Relationships Among Factors Related to Childbirth and Breastfeeding Outcomes in Primiparous Women

ObjectivesTo explore the relationships among potentially modifiable factors related to childbirth and effective breastfeeding initiation at approximately 36 hours after birth and duration and exclusivity at hospital discharge, 2 weeks, 2 months, and 6 months after birth in primiparous women and to explore whether modifiable and nonmodifiable secondary factors and covariates influenced the relationships among factors related to childbirth and these breastfeeding outcomes.DesignA prospective, longitudinal, cohort study.SettingThe postpartum units of two general hospitals in eastern Canada.ParticipantsNinety-seven mother–infant dyads.MethodsWe recorded demographic, childbirth, obstetric history, and breastfeeding data through chart review. A breastfeeding observation was completed at approximately 36 hours after birth by unit nurses. Participants maintained breastfeeding logs in hospital and for 6 months after birth and completed three self-report questionnaires before discharge. We analyzed outcomes using backward stepwise linear and logistic regression.ResultsOne childbirth factor, labor induced with oxytocin, was negatively associated with effective initiation of breastfeeding, and none was related to breastfeeding duration and exclusivity at any time point. Maternal weight; professional support; and newborn’s gestational age at birth, 5-minute Apgar score, weight loss, LATCH score, and active feeds (newborn actively suckled at the breast) were significantly associated with breastfeeding outcomes.ConclusionInduction of labor with oxytocin should be used judiciously; when used, nurses must be hypervigilant to assess the mother–infant dyad for breastfeeding issues and to intervene to prevent or remediate them.     

安息香药材化学成分、药理作用研究进展及质量标志物预测分析＊

安息香为安息香科白花树Styrax tonkinensis （Pierre） Craib ex Hart.的干燥树脂，主要化学成分为香脂酸类和三萜类物质，及少数木脂素类物质，其中香脂酸类化合物是其主要活性成分。安息香主要药理活性有抗炎解热、抗肿瘤、血脑屏障保护等。本文对安息香药材的化学成分和药理作用进行了综述，并从多角度分析预测了安息香可能的质量标志物，为安息香药材的质量控制、合理开发与利用提供参考。     

Hair shaft miRNA‐221 levels as a new tumor marker of malignant melanoma

miRNA‐221 (miR‐221) is known to be abnormally expressed in many human cancers. The serum levels of miR‐221 have been reported as a tumor marker for malignant melanoma (MM). We hypothesized that the hair shaft miR‐221 levels may be increased in patients with MM. We therefore assessed the possibility that hair shaft miR‐221 levels could be a marker for MM. The hair shaft miR‐221 levels were significantly higher in patients with MM than controls. The rates of increased hair shaft miR‐221 levels above the cut‐off value were comparable to those of serum 5‐S‐CD, which is a tumor marker commonly used for MM. Measurements of the hair shaft miR‐221 levels could have potential clinical value in the detection of MM. This is the first report investigating the hair shaft levels of an miRNA in patients with MM. Our investigations offer new insight into the relationship between miR‐221 and MM, and may provide a new, non‐invasive way to screen for melanoma.     

Does Outcome/Survival of Patients With Myelodysplastic Syndromes Should Be Predicted by Reduced Levels of ADAMTS-13? Results From a Pilot Study

IntroductionVon Willebrand factor (vWF) cleaving protease ADAMTS-13 has a key role for maintaining normal size of vWF. A deficiency or dysfunction of vWF cleaving protease is associated with ultra large vWF multimers and thrombotic microangiopathy. Patients with cancers have reduced levels of vWF cleaving protease. In this pilot study, we have evaluated whether or not deficiencies of ADAMTS-13 were present in myelodysplastic syndromes (MDS). Moreover, we assessed if a reduction in basal levels of ADAMTS-13 may play a role in the prognosis of MDS.Patients and MethodsWe measured and compared the levels of vWF cleaving protease ADAMTS-13 in 100 patients with MDS and 35 healthy controls. Patients were divided into 2 groups according to the International Prognostic Scoring System: group I consisting of 44 patients with low-risk MDS and group II of 56 patients with high-risk MDS. Patients with high-risk and low-risk MDS presented significantly lower levels of ADAMTS-13 than controls (P < .001 and P = .0177, respectively). High-risk patients had significantly lower levels of ADAMTS-13 when compared with the low-risk group (P < .001).ResultsWe found that reduced levels of ADAMTS-13 have a relationship with overall survival (P < .001). Statistical analysis showed that ADAMTS-13 correlates with cytogenetics (P < .001) and a tendency of slight correlation with platelet count and basal levels of ADAMTS-13 (R, 0.35; P value, 0.001). Moreover, we found that levels of ADAMTS-13 have correlation with response to treatment (P < .001).ConclusionsADAMTS-13 in MDS might represent a surrogate marker of prognosis, response to therapy, or disease progression. Further studies are needed.     

基于中药质量标志物和传统用法的中药饮片标准汤剂传承发展研究思路与建议

中药汤剂(也称煎剂)是中医师最常用的中药复方剂型,也是中药历史上应用最久和最广的制剂。药材是饮片的原料,饮片是制备提取物、构成中医处方和中药制剂的原料,更体现了传承发展中药的重要性。基于中药饮片标准汤剂,科学认识汤剂质量,提高药典饮片和中成药质量评价研究理论和方法是科学发展的重要策略。开展以中医药理论为指导、临床应用为基础的中药饮片标准汤剂研究,基于中药质量标志物理论和研究方法探讨饮片和煎煮工艺的影响,形成标准汤剂的质量评价体系,既有利于确保中医处方用药的安全和疗效,也有利于认识标准汤剂在"药材-饮片-中成药"的质量及其标准的差异和价值,提升国家对中药饮片监管水平,保障人民用药安全和有效;还有利于认识标准汤剂在中药饮片生产、中药配方颗粒及经典名方的传承研发中的重要意义。     

六西格玛在肿瘤标志物质量目标选择上的应用

目的应用6σ理论对肿瘤标志物项目的分析性能进行评价，并初步确定各项目的质量目标。 方法收集本实验室2018年1至12月室内质控数据和国家卫生健康委临床检验中心室间质量评价结果，以生物学变异导出的质量规范和国家室间质量评价标准作为允许总误差(TEa)计算6项肿瘤标志物的σ水平，并依据质量目标选择流程图和肿瘤标志物分析性能验证图评价肿瘤标志物的分析性能，进而为肿瘤标志物选择合适的质量目标。 结果应用不同层级的生物学变异导出的质量规范和国家室间质量评价标准，肿瘤标志物项目的σ水平存在显著差异；依据质量目标选择流程图：选择生物学变异导出的"适当的"质量规范作为CA125项目的质量目标，选择生物学变异导出的"最低的"质量规范作为t-PSA、CEA、AFP、CA199和CA153项目的质量目标。 结论6σ能够客观评价肿瘤标志物的分析性能，并为实验室质量目标的选择提供重要的参考价值。     

缺血修饰性白蛋白在急性缺血性胸痛中的诊断价值

目的 评价缺血修饰性白蛋白（ischemia modified albumin，IMA）对急性缺血性胸痛（ICP）的早期诊断价值。方法 时206例发病〈12h、表现为急性胸痛的患者立即行12导联心电图（ECG）检查，并抽血进行IMA、肌钙蛋白I（cTnI）、肌酸激酶同工酶MB（CK-MB）测定。将ECG、IMA、cTnI、CK-MB的结果单独或结合与最终诊断为非缺血性胸痛（NICP）及ICP的相互关系进行比较。结果 最后诊断为ICP98例，NICP108例，ICP发病〈3h和3-6h组IMA水平明显升高，与NICP组比较差异有统计学意义（P〈0．001）；ICP发病〉6h组IMA水平与NICP组比较差异无统计学意义（P〉0．05）。IMA诊断发病〈3hICP的敏感性和阴性预测值（NPV）为89．1％和88．8％，明显高于ECG、cTnI和CK-MB，四者结合为97．6％和96．9％；IMA诊断发病3～6hICP的敏感性和NPV为71．7％和74．5％，也高于ECG、cTnI、CK-MB，四者结合为95．5％和94．2％；但IMA对于发病〉6h的ICP则无诊断作用。结论 IMA是诊断ICP的早期敏感生化指标，对于发病〈6h（尤其是〈3h）的ICP诊断具有较高的敏感性和NPV，优于ECG、CK-MB、cTnI；将IMA与其他指标结合，可进一步提高对ICP的诊断价值。     

Fast CT-PRESS-based spiral chemical shift imaging at 3 Tesla.

A new sequence is presented that combines constant-time point-resolved spectroscopy (CT-PRESS) with fast spiral chemical shift imaging. It allows the acquisition of multivoxel spectra without line splitting with a minimum total measurement time of less than 5 min for a field of view of 24 cm and a nominal 1.5x1.5-cm2 in-plane resolution. Measurements were performed with 17 CS encoding steps in t1 (Deltat1=12.8 ms) and an average echo time of 151 ms, which was determined by simulating the CT-PRESS experiment for the spin systems of glutamate (Glu) and myo-inositol (mI). Signals from N-acetyl-aspartate, total creatine, choline-containing compounds (Cho), Glu, and mI were detected in a healthy volunteer with no or only minor baseline distortions within 14 min on a 3 T MR scanner.