Advances on circulating fetal DNA in maternal plasma

The discovery of cell-free fetal DNA in maternal plasma in 1997 has opened up new possibilities for noninvasive diagnosis. By RT-PCR, circulating fetal DNA can be detected in the plasma of pregnant women, even in the first trimester of pregnancy, and thus can be used for noninvasive prenatal diagnosis of sex-linked disorders, the RhD status of fetuses, and single gene disorders such as beta-thalassaemia, congenital adrenal hyperplasia, and achondroplasia. In addition, quantitative aberrations of circulating fetal DNA may indicate various pregnancy-associated disorders, including preeclampsia, preterm labor and fetal trisomy 21.[第一段]     

Application of Fetal DNA in Maternal Plasma in Noninvasive Prenatal Diagnosis

To explore the application of fetal DNA in maternal plasma for noninvasive prenatal diagnosis, the DNA template was extracted by hydroxybenzene-chloroform from 44 maternal (7-41 weeks) plasma. The Fetus-derived Y sequence DYZ-1 gene (149bp) was chosen to be amplified by PCR. The fragment was identified in all the plasma of male bearing pregnant women with the diagnostic accordance rate being 100.00 %. Two of the 22 female bearing pregnant women had false positive results. Among the 44 pregnant women, the diagnostic accordance rate was 88. 89 % at early pregnant stage, 100.00% at medium pregnant stage, and 96.55 % at late stage respectively.The final accuracy of 95.45% was obtained in all cases. It was concluded that by means of hydroxybenzene-chloroform extraction the authors of this article promoted the concentration and purity of the DNA template, and diagnosed more accurately. The results showed that free fetal DNA in the maternal plasma could be regarded as the gene resource for noninvasive prenatal diagnosis.     

Comparison of three methods for the gene analysis of fetal cells from maternal peripheral blood

Background Although great advances in techniques for noninvasive prenatal diagnosis using fetal cells from maternal peripheral blood have achieved, current technology does not meet the demand srequired for clinical use. In this study, we aimed to establish reliable methods for the gene analysis of fetal cells from maternal peripheral blood.Methods Primed extension preamplification (PEP)-polymerase chain reaction (PCR), multiple primed in situ labeling (PRINS), and nested PCR were individually applied to detect the sex determining region Y (SRY) gene in single fetal cells collected from maternal peripheral blood.Results The sensitivity and specificity of the detection of the SRY gene by PEP-PCR were 97. 39%(149/153) and 99. 17% ( 119/120 ), respectively. The sensitivity and specificity of PRINS were 97. 56% (40/41) and 100% (35/35), respectively. The sensitivity and specificity of nested-PCR were 80. 00% (24/30) and 87. 50% (14/16), respectively.Conclusions PEP-PCR and PRINS are reliable techniques for the gene analysis of single fetal cells from maternal peripheral blood because of their high sensitivity and specificity. PEP-PCR and PRINS can be used as standard methods of noninvasive prenatal diagnosis using single fetal cells from maternal peripheral blood.     

Noninvasive Prenatal Diagnosis of Fetal Sex by Single-cell PEP-PCR Method

A new method for noninvasive prenatal diagnosis of fetal sex was developed by using single-cell PEP-PCR techniques. Micromamipulation techniques were used to obtain single fetal cells from 273 maternal blood samples. The genome of single cells was preamplified by PEP and SRYgenes were analyzed by PCR method. The SRY genes of 149 samples were detected by the new method among 153 samples carrying male fetus, while 119 out of 120 samples carrying female fetuswere proved negative for SRY genes. The sensitivity and specificity of the new method were 97.39% and 99.17% respectively and the correct rate was 98.17%. The new method has the advantage of high sensitivity and specificity in noninvasive prenatal diagnosis of fetal sex and provides the basis of other researches such as sex-linked inherited diseases.     

Non-invasive prenatal diagnosis of trisomy 21 by dosage ratio of fetal chromosome-specific epigenetic markers in maternal plasma

This study examined the methylation difference in AIRE and RASSF1A between maternal and placental DNA,and the implication of this difference in the identification of free fetal DNA in maternal plasma a...     

中国大陆产前诊断的现状和前景

1The history and main problems in prenatal diagnosis and clinical diagnosis of inherited diseasesPrenatal diagnosis is to diagnose the fetal congenital defects and inherited diseases.In the earlier1970s,thegroup of prenatal diagnosis in Peking Union Hospi…     

Comparison of second-trimester maternal serum free-p-human chorionic gonadotropin and a-fetoprotein between normal singleton and twin pregnancies： a population-based study

Background The second-trimester maternal serum screening in twin pregnancy is still controversial, as the serum marker levels in twins are not as clear as those in singletons. This study aimed to evaluate the relationship between the levels of the second-trimester maternal serum free β-human chorionic gonadotropin （free β-HCG） and a-fetoprotein （AFP） in normal twin and singleton pregnancies and to estimate feasible analysis methods for utilizing these markers in second trimester screening for twin pregnancy. Methods On the basis of a prospective population-based study of second-trimester maternal serum screening, the concentrations of maternal serum AFP and free β-HCG of 195 normal twin pregnancy and 26 512 singleton controls at gestational weeks 15 to 20 were measured by time-resolved fluoroimmunoassay in one laboratory. The levels of markers were compared between the twins and singletons using weight-correction and gestational age-specific model. Results According to the research protocol, 95 communities were randomly sampled, which covered the whole Jiangsu province, the east of China. A total of 26 803 pregnant women （98%）, from the target population accepted prenatal screening for maternal serum AFP, β-HCG detection, and all babies were followed up for at least six months. There were 197 （0.73%） twin pregnancies, of which one case had fetal trisomy 18, and one case with fetal anencephaly. The others were normal twin pregnancy. From a total enrollment of 26 803 women participants, 26 512 women with normal singleton pregnancies were selected as the model controls. The other 291 pregnancies, including trisomy 21, neural tube defect （NTD）, trisomy 18, and other fetal abnormalities, were excluded. No significant differences were found in the medians of gestational age-specific maternal serum free β-hCG and AFP in normal twin pregnancy comparing with twice those in model controls with the exception of the medians for free β-hCG during the 16th gestational week （P=0.012）. Conclusion The weight-correction and gestational age-specific levels of Chinese Han population maternal serum free β-hCG and AFP in normal twins were twice the levels as those in the singleton controls during the 17-19 gestational weeks.     

Use of amniocytes for prenatal diagnosis of 22q11.2 microdeletion syndrome: a feasibility study

Background A study of prenatal genetic diagnosis for 22q11.2 microdeletion, which has a wide phenotypic spectrum that involves almost all organs, is rarely reported in China. This study aimed to explore the prevalence of 22q11.2 microdeletion in congenitally malformed fetuses via the fluorescent in situ hybridization （FISH） technique and to investigate the feasibility of use of amniocytes to diagnose 22q11 .2 microdeletion syndrome prenatally. Methods The study enrolled 23 cases of fetal cardiac malformation, as indicated by ultrasound in Beijing Anzhen Hospital and 14 cases of non-cardiac malformation, as determined by type-B ultrasound in Beijing Anzhen Hospital and other hospitals. Amniotic fluid was obtained by amniocentesis before odinopoeia, and the stillborn fetuses of the induced labor were preceded to autopsy. The amniotic fluid of 20 cesarean deliveries during the same period of time was used as a control. The TUPLE1 gene in the amniotic fluid of malformed and normal fetuses was assessed by the FISH method. Results The prevalence rates of the TUPLE1 gene deletion in the amniotic fluid cells from fetuses with cardiac deformations and fetuses without such malformations were 43.5% and 57.1%, respectively. The deletion of TUPLE1 was significantly associated with fetal malformation. Conclusion Chromosome 22q11.2 microdeletion is one of the major factors leading to fetal congenital malformations, and prenatal FISH screening for 22q11 .2 microdeletion syndrome is technically feasible using amniocytes.     

Prenatal cytogenetic diagnosis study of 2782 cases of high-risk pregnant women

Background Prenatal diagnoses are extremely advantageous for pregnant women with high-risk indicators and can help prevent the birth of malformed infants. However, no large-scale statistical study analyzing the correlation between fetal chromosome disorders and abnormal indicators during pregnancy has been done in China. The objectives of this study were to diagnose and analyze fetal chromosome abnormalities, determine the feasibility of the various prenatal test methods and establish diagnostic guidelines for the early, middle, and late trimesters. Methods From January 2004 to May 2009, 2782 pregnant women at high-risk underwent prenatal diagnoses. Categorized data expressed as either actual counts or percentages were analyzed by the chi-square or Fisher＇s exact test. Chorionic villus sampling was performed in the early-trimester （10-12 weeks of gestation）, amniocentesis in mid-trimester （16-28 weeks of gestation）, and umbilical cord blood collection in mid- or late-trimester （16-37 weeks of gestation）. In 51 cases either autopsy samples from intrauterine fetal deaths or placental tissues from aborted fetuses were tested. Results Chromosomal abnormalities were observed in 3.99% （111/2782） of the samples. Overall, the success rate of cytogenetic analysis for high-risk pregnancy groups was 98.17% （2731/2782）. It was significantly less successful when used to analyze data from the chorionic villus sampling compared with that from amniocentesis and umbilical cord blood （P=-0.000）. Abnormal chromosome carriers had the highest percentage of abnormal chromosomes （67.86%） when compared with chromosomal abnormalities in patients with ultra-sonographic ＂soft markers＂ （11.81%）, advanced maternal age （4.51%） and those who had positive serum screening results （P=-0.000）. Conclusions Invasive prenatal diagnostic techniques are feasible tools for confirming fetal chromosomal abnormalities. Abnormal chromosomes detected in one of the parents carrying abnormal chromosome, ultrasound soft markers, advanced maternal age or positive serum screening results were associated with a higher frequency of fetal genetic diseases.     

Effects of pre-pregnancy body mass index on pregnancy outcomes

Prevalence of overweight and obesity has continued to increase among women of child bearing age all over the world in recent decades. Its impact on short-term and long-term maternal and fetal outcomes continued to grow, such as increased risk of gestational diabetes mellitus, gestational hypertension, preeclampsia, fetal macrosomia, perinatal mortality and chance for cesarean deliveries） What＇s more, underweight before pregnancy also has some hazardous effects on pregnant women and fetus, such as increased risk of delivering infants small for gestational age and preterm delivery.2 The present study determined the prevalence of each body mass index （BMI） group of an obstetric population of the mainland of China, and effects of the maternal pre-pregnancy BMI on multiple antepartum, intrapartum and neonatal outcomes.     

Prenatal diagnosis of Down syndrome using cell-free fetal DNA in amniotic fluid by quantitative fluorescent polymersase chain reaction

Backgroud Amniotic fluid （AF） supernatant contains cell-free fetal DNA （cffDNA） fragments.This study attempted to take advantage of cffDNA as a new material for prenatal diagnosis,which could be combined with simple quantitative fluorescent polymerase chain reaction （QF-PCR） to provide an ancillary method for the prenatal diagnosis of trisomy 21 syndrome.Methods AF supernatant samples were obtained from 27 women carrying euploid fetuses and 28 women carrying aneuploid fetuses with known cytogenetic karyotypes.Peripheral blood samples of the parents were collected at the same time.Short tandem repeat （STR） fragments on chromosome 21 were amplified by QF-PCR.Fetal condition and the parental source of the extra chromosome could be determined by the STR peaks.Results The sensitivity of the assay for the aneuploid was 93％ （26/28; confidence interval,CI：77％-98％） and the specificity was 100％ （26/26; CI：88％-100％）.The determination rate of the origin of the extra chromosome was 69％.The sensitivity and the specificity of the assay in the euploid were 100％ （27/27）.Conclusions Trisomy 21 can be prenatally diagnosed by the QF-PCR method in AF supernatant.This karyotype analysis method greatly reduces the requirement for the specimen size.It will be a benefit for early amniocentesis and could avoid pregnancy complications.The method may become an ancillary method for prenatal diagnosis of trisomy 21.     

Saffron （Crocus sativus L.） and major depressive disorder： a meta-analysis of randomized clinical trials

Due to safety concerns and side effects of many antidepressant medications, herbal psychopharmacology research has increased, and herbal remedies are becoming increasingly popular as alternatives to prescribed medications for the treatment of major depressive disorder （MDD）. Of these, accumulating trials reveal positive effects of the spice saffron （Crocus sativus L.） for the treatment of depression. A comprehensive and statistical review of the clinical trials examining the effects of saffron for treatment of MDD is warranted. OBJECTIVE： The purpose of this study was to conduct a meta-analysis of published randomized controlled trials examining the effects of saffron supplementation on symptoms of depression among participants with MDD. SEARCH STRATEGY： We conducted electronic and non-electronic searches to identify all relevant randomized, double-blind controlled trials. Reference lists of all retrieved articles were searched for relevant studies. INCLUSION CRITERIA： The criteria for study selection included the following： （1） adults （aged 18 and older） with symptoms of depression, （2） randomized controlled trial, （3） effects of saffron supplementation on depressive symptoms examined, and （4） study had either a placebo control or antidepressant comparison group. DATA EXTRACTION AND ANALYSIS： Using random effects modeling procedures, we calculated weighted mean effect sizes separately for the saffron supplementation vs placebo control groups, and for the saffron supplementation vs antidepressant groups. The methodological quality of all studies was assessed using the Jadad score. The computer software Comprehensive Meta- analysis 2 was used to analyze the data. RESULTS： Based on our pre-specified criteria, five randomized controlled trials （n = 2 placebo controlled trials, n = 3 antidepressant controlled trials） were included in our review. A large effect size was found for saffron supplementation vs placebo control in treating depressive symptoms （M ES = 1.62, P 〈 0.001）, revealing that saffron supplementation significantly reduced depression symptoms compared to the placebo control. A null effect size was evidenced between saffron supplementation and the antidepressant groups （M ES = -0.15） indicating that both treatments were similarly effective in reducing depression symptoms. The mean Jadad score was 5 indicating high quality of trials. CONCLUSION： Findings from clinical trials conducted to date indicate that saffron supplementation can improve symptoms of depression in adults with MDD. Larger clinical trials, conducted by research teams outside of Iran, with long-term follow-ups are needed before firm conclusions can be made regarding saffron＇s efficacy and safety for treating depressive symptoms.     

Association between intervertebral disc degeneration and disturbances of blood supply to the vertebrae

Low back pain is a common public health problem in western industrialized societies and the world as well.Studies indicate that the prevalence rate ranges to 35%, with around 10% of patients from 12% becoming chronically disabled. It also places an enormous economic burden on society. Although the exact cause of low back pain has yet to be defined, intervertebral disc degeneration is considered a major source of it. Since patients with degenerative discs are often asymptomatic, the mechanisms of it are still unclear.     

Relevance of muscle biopsy for diagnosing multifocal motor neuropathy

Multifocal motor neuropathy （MMN） is a rare,.focal,inflammatory,demyelinating disease of the peripheral nerves with pure motor involvementJ MMN is clinically characterized by slowly progressive,asymmetric,distal,upper limb predominant weakness,in the absence of sensory disturbances） Weakness is usually multifocal and connected to a distinct motor nerve,such as the musculocutaneous nerve resulting in biceps weakness,the posterior interosseus nerve resulting in finger drop,the median,ulnar,or radial nerve resulting in dexterity problems or grip weakness,or the peroneal nerve resulting in a foot drop.Onset of clinical manifestations is between 20 and 50 years of age.The prevalence of MMN is reported as 1-2 per 100 000.2 MMN is three times more frequent in men as compared to women.     

痘苗病毒天坛株的减毒与其作为疫苗载体研究进展

1痘苗病毒天坛株的历史天花是人类历史上最可怕的传染病之一。天花由天花病毒（variola virus）引起,人是该病毒的惟一宿主。人感染天花病毒后的死亡率达到30%~40%[1]。世界上公认的对天花最早的准确记录来自中国,晋代药学家葛洪于公元430年左右,在《肘后备急方》中对天花有清楚的描述[1]。     

The role of central nervous system on hypoglycemia and the feasibility of the brain theory in traditional Chinese medicine on treatment of diabetes mellitus

The central nervous system （CNS） plays a key regulatory role in glucose homeostasis. In particular, the brain is important in initiating and coordinating protective counterregulatory responses when blood glucose levels fall. This may due to the metabolic dependency of the CNS on glucose, and protection of food supply to the brain. In healthy subjects, blood glucose is normally maintained within a relatively narrow range. Hypoglycemia in diabetic patients can increase the risk of complications, such as heart disease and diabetic peripheral neuropathy. The clinical research finds that the use of traditional Chinese medicine （TCM） has a positive effect on the treatment of hypoglycemia. Here the authors reviewed the current understanding of sensing and counterregulatory responses to hypoglycemia, and discuss combining traditional Chinese and Western medicine and the theory of iatrogenic hypoglycemia in diabetes treatment. Furthermore, the authors clarify the feasibility of treating hypoglycemia on the basis of TCM theory and CNS and have an insight on its clinical practice.     

WHO西太区与世界中医药学会联合会中医名词术语国际标准比较研究：八纲辨证（三）

The Chinese characters 寒 and 热, 虚, and 实 are quite common concepts in Chinese language. However in traditional Chinese medicine （TCM）, they are used as four principles in syndrome differentiation. In terms of translation, 寒 and 热 are very easy to understand and can be simply translated as ＂cold＂ and ＂heat＂. But the transla- tion of 虚 and 实 used to be a problem. For a quite long time in translation practice,     

Gene expression profiles of ERCC1, TYMS, RRM1, TUBB3 and EGFR in tumor tissue from non-small cell lung cancer patients

Background Personalized medicine becomes essential in lung cancer treatment, however lung-cancer-related gene expression profiles in Chinese patients remain unknown. In this study, the correlation of gene expression profiles and clinical characteristics in non-small-cell lung cancer （NSCLC） was investigated. Methods Seventy-six Chinese patients with NSCLC were enrolled in the study to investigate mRNA expression profiles of excision repair cross complement group 1 （ERCC1）, thymidylate synthetase （TYMS）, ribonucleotide reductase （RRM1）, class Ill 13-tubulin （TUBB3）, and epidermal growth factor receptor （EGFR） genes and their correlation with patient clinical characteristics. A novel liquidchip technology was used to detect mRNA expression levels in formalin fixed paraffin embedded tumor pathology samples. The relationships between gene expression and clinical characteristics were assessed using the Mann-Whitney test. Results ERCC1 mRNA levels were higher in tumors from patients with metastatic disease than patients with non- metastatic disease （P=-0.021）, and higher in adenocarcinomas than squamous cell carcinomas （P=0.006）. Increased TUBB3 mRNA expression levels were found in patients with performance status （PS） 1 in comparison with PS 0 （P=0.049）, with poorly differentiated tumors in comparison with tumors that were moderately and well differentiated （P 〈0.000 1）, and with advanced stage in comparison with early stage disease （P 〈0.000 1）. Conclusions ERCC1 mRNA levels were higher in metastatic adenocarcinoma NSCLC; TUBB3 mRNA levels were significantly higher in poorly differentiated tumors and in advanced stage NSCLC, which indicates the poor prognosis.