Objective:To analyze the indications for invasive prenatal diagnosis in the third trimester and summarize the pregnant outcome.Methods:Clinical data of 121 women who underwent invasive prenatal diagnosis in the third trimester in the prenatal diagnostic center of the First Medical Center of Chinese PLA General Hospital from January 2016 to December 2020 was retrospectively analyzed. Different genetic diagnostic methods were used according to different indications. Indications and results of prenatal diagnosis, as well as the complications within two weeks after the invasive procedure, pregnancy outcome, and neonatal follow-up of all the participants were described.Results:Among the 121 cases, 107 cases underwent amniocentesis, seven underwent percutaneous umbilical blood sampling, and seven had both procedures performed at the same time (one underwent thoracocentesis at the same time). Newly identified ultrasound abnormalities in the second and third trimesters were the main indications for prenatal diagnosis, accounting for 99.2%(120/121), of which short limbs and fetal growth restriction accounted for 25.0% (30/120) and 20.0% (24/120), respectively. Genetic abnormalities and congenital diseases were detected in 20 cases with a detection rate of 16.5%(20/121). Among them, there were nine cases of achondroplasia, five cases of pathogenic copy number variations, one case of achondroplasia with pathogenic copy number variation, one trisomy 18, one 47,XXX, one tetrasome mosaicism of 12p, one de novo WTX c. 1072(Exon2) C>Tp.R358X heterozygous mutation, and one fetal hypoproteinemia. In addition, six cases with copy number variation of unknown significance (VUS) were detected, noting for a detection rate of 5.0%(6/121). Among the 20 cases with abnormal detection, 15 were terminated, two delivered prematurely before obtaining the prenatal diagnosis results, one underwent cesarean section before obtaining prenatal diagnostic results and two continued the pregnancies. In the six cases with VUS, one was terminated and the other five continued the pregnancy. Only one case had preterm premature rupture of membranes 2 d after amniocentesis and the incidence rate of complications after all kinds of invasive procedures was 0.8% (1/121). During the neonatal follow-up, postnatal whole exome sequencing revealed monogenetic disorder in two cases with normal prenatal diagnostic results; the patient with 12p chimerism had developmental delay; the one with WTX mutation deceased on the day of born; the rest newborns developed normally. Conclusions:As a relatively safe method, invasive prenatal diagnosis in the third trimester is of great importance and value in reducing the miss diagnostic rate of fetuses with severe genetic diseases and birth defects. The appropriate application of prenatal whole exome sequencing could further help to decrease the miss diagnostic rate of monogenetic disorder.

Objective To investigate pathogenic genes related to the phenotype of fetus with severely short limbs in the first and second trimester by whole exome sequencing (WES). Methods Thirteen fetuses with severely short limbs detected by ultrasonography in the first and second trimester admitted in Chinese PLA General Hospital from September 2016 to June 2018 were collected. All cases were performed induced abortion, 6 of which were carried out karyotype analysis of amniotic fluid at the same time. WES and copy number variations (CNV) were performed on specimens from fetal tissues after labor induction. The suspected pathogenic mutations were validated by Sanger sequencing reactions. Results No abnormal karyotypes or pathological CNV were found. In 10 fetuses, pathogenic or possibly pathogenic mutations were detected in the following genes: COL2A1, FGFR3, COL1A1, COL1A2, DYNC2LI1 and TRIP11, all of which were essential to skeletal development. The diagnostic yield of WES in the fetuses with severe short limbs was 10/13. Conclusions In the first and second trimester, most of the fetuses with extremely short limbs suffer from monogenic diseases. WES is likely to be a valuable diagnostic testing option for the fetuses with severe short limbs.

Objective To analyze the imaging features of solitary pulmonary nodules (SPN).Methods The clinical data and chest imaging features of 55 cases with SPN confirmed by pathology were retrospectively analyzed . Results Of the 55 patients,40 cases (80.00％) were lung cancer and 15 cases (20.00％) were benign lesions . The univariate analysis showed that the age of patients (t=2.972,P=0.004),lobulation sign (χ2 =7.018,P=0.008) and pleural indentation sign (χ2 =4.727,P=0.030) had statistically significant differences in distinguish of the benign and malignant nodules ,but the sex (χ2 =1.760,P=0.185),nodule site (χ2 =0.145,P=0.703),burrs (χ2 =0.555,P=0.456),cavity (χ2 =0.000,P=1.000),nodule size (t=0.608,P=0.546) and other factors had no significant difference.Multivariate Logistic regression analysis showed that age (OR=1.101,P=0.022) and lobulation sign (OR=6.187,P=0.026) were independent influencing factors for judgement of the benign and malig -nant SPN.Conclusion The age of patients,lobulation sign and the pleural indentation sign are related to the benign and malignant SPN .Age and lobulation sign are the independent influencing factors for judgement of the benign and malignant SPN .

Objective To analyze ultrasonographic imaging feature of primary fallopian tube carcinoma (PFTC) and the reasons for misdiagnosis.Methods Clinical data and ultrasonographic imaging feature of 41 patients with pathologically confirmed PFTC were retrospectively analyzed from August 2008 to November 2016 in General Hospital of Chinese People's Liberation Army.Results Ultrasonographic characteristics of 41 PFTC cases:(1) Type Ⅰ (6 cases),the cystic adnexal mass with single or multiple papillary projections and circuity tubular structures,color Doppler flow imaging showed abundant blood flow signal inside the nipples.(2) Type Ⅱ (2 cases),the sausage shaped complex adnexal mass showed clear boundary,the cystic area that lined along the fallopian tube was around or at the side of the solid part,color Doppler flow imaging showed rich or abundant blood flow signal inside the solid part.(3) Type Ⅲ (13 cases),the sausage shaped hypoechoic adnexal mass showed clear boundary,color Doppler flow imaging showed rich or abundant blood flow signal inside the mass.(4) Type Ⅳ (14 cases),the single or multiple adnexal masses showed irregular surface,with predominant solid components,color Doppler showed rich or abundant blood flow signal inside the tumor;the normal ovarian structure was not detected in unilateral or bilateral adnexa area;and one or more signs of metastasis were found,such as the peritoneal thickening of vesicouterine pouch,uterine rectum pouch and omental,metastasis to other distant organs,and so on.(5) Type Ⅳ (6 cases),only hydrosalpinx or no abnormal ultrasonographic changes in the adnexal area.Nineteen (46.3％,19/41) cases were correctly diagnosed by preoperative ultrasonography,while 22 (53.7％,22/41)cases were missed or misdiagnosed.Conclusions Ultrasonography imaging of PFTC has certain characteristics,but it tends to be missed or misdiagnosis when the lesion is small.Ultrasound can show the location,size,internal echo,blood flow and distant metastasis of lesion,which can be taken as the first choice of imaging methods for preoperative diagnosis and postoperative follow-up of PFTC.

Objective To explore the ultrasonographic imaging characteristics of placenta increta and clinical data, and analyze the reasons for failure to make an accurate diagnosis. Methods By means of a retrospective analysis of 27 patients with placenta increta confirmed by operation and pathologic examination from January 2014 to May 2017 in the General Hospital of the People's Liberation Army (also Hospital 301 for short), the reasons for missed diagnosis and misdiagnosis are comprehensively summarized. Results The ultrasound examination in all the 27 cases (5 cases of first pregnancy, 17 cases of scar, 5 cases of maternal) illustrated the poorly-defined boundary between placenta and uterus mesometrium, the loss of retroplacental space, multiple lacunae echo areas, and the incomplete high-echo area of the serous membrane of placenta and bladder (involving the bladder); despite 3 normal placenta, the rest 24 were all diagnosed as placenta previa before operation, of which 20 belonged to central placenta previa and the other 4 belonged to marginal placenta previa. Twenty liveborn infants were delivered in the study, 13 of them went through abdominal hysterectomy after cesarean section surgery, 8 of them only received cesarean section surgery; 2 of them went through vaginal hysterectomy, 1 received cesarean section surgery after interventional embolization, 1 Uterine rupture in utero before got to the hospital, with the rest 2 received interventional embolization clamp scraping as a consequence of deadly induced labor or stillbirth. Postoperative placenta increta types demonstrated adhensive implantation, penetrating implantation, and implantation into muscular but not membrane layer in 3, 2, and 22 cases respectively. In terms of implanting position, only 3 patients (3/17) with cicatricial uterus did't undergo the implantation into the scar area mainly in the left wall, left anterior wall and posterior wall, as for patients with non-scar uterus, posterior wall implantation was the main mode presented in 6 cases (6/10). Fifteen of all the involved 27 cases were identified while 12 cases failed to be distinguished. The deep reasons of misdiagnosis were placental location (placenta adheres to the posterior wall), fetal head shelter, or small placental placement, gestational age, larger range of placenta implantation, emergency ultrasound only pay attention to the emergency situation and ignore the exist at the same time, experience of inspectors with placenta increta and so on. Conclusions Although there are some limitations in prenatal ultrasound diagnosis of placenta, it is still an important method for the diagnosis and prenatal dynamic monitoring of the condition before the placenta implantation.

PurposeTo evaluate the safety and feasibility of transabdominal ultrasound guided multifetal pregnancy reduction performed in the second trimester.Materials and Methods Forty-three women receiving embryo implantation were divided into two groups according to whether they have received multifetal pregnancy reduction including 16 in the reduction group in the second trimester to reduce multiple fetuses to twins, and 27 with twin pregnancy and no reduction. The pregnancy outcome was compared.Results In the reduction group, 1 patient had miscarriage because of intrauterine infection; 1 patient lost one of the retained fetuses in two days after reduction and delivered the remaining fetus. In the other 14 cases, 8 delivered and 6 were still in pregnancy. This group had 17 newborns, all without neonatal death or birth defects. In the non-reduction group, there was 1 spontaneous abortion. In 2 patients, 1 of the twin embryos stopped development. 1 case had a spontaneous abortion, the other 24 cases delivered uneventfully. There were 50 newborns in this group with 3 birth defects and no neonatal death. There was no statistically significant difference in gestational age at delivery, birth weight, and the incidence of maternal and neonate complications (P>0.05).Conclusion Multifetal reduction improves pregnancy outcomes, similar to non-reduction twin pregnancy. It is safe and feasible to perform multifetal pregnancy reduction in the second trimester.

Aim To investigate the role of miR-125 b and its DNA methylation in homocysteine ( Hcy )-in-duced vascular smooth muscle cells( VSMCs) prolifera-tion. Methods VSMCs were stimulated with 0,50, 100, 200, 500 μmol · L-1 Hcy respectively. Then qRT-PCR was used to detect the mRNA levels of miR-125b,and nested-touchdown methylation-specific PCR ( ntMS-PCR) was used to detect the methylation levels of miR-125b. VSMCs were transfected with miR-125b precursor or the inhibitor of miR-125b ,then 3-(4,5-dimethylthiazol-2-yl)-2-5-diphenyl tetrazolium bromide ( MTT ) assay was used to reflect the proliferation of VSMCs. The distribution of CpG islands of miR-125b promoter region was analyzed by bioinformatics meth-ods. VSMCs were stimulated with 100 μmol·L-1 Hcy and transfected with or without DNA methylation inhib-itors 5-nitrogen impurity cytidine ( AZC) , then the ex-pression of miR-125b was detected by qRT-PCR. Re-sults The mRNA levels of miR-125 b were decreased in 100,200,500 μmol·L-1 Hcy group compared with 0 μmol·L-1 Hcy group. The precursor of miR-125b could inhibit the proliferation activity and the inhibitor of miR-125 b could increase the proliferation activity of VSMCs cells. Bioinformatics analysis indicated that MiR-125 b promoter region had a CpG island whose length was 792 bp ( 1881-2672 ) . The miR-125 b pro-moter region methylation levels increased after Hcy in-tervention ( P <0. 01 ) . The expression level of miR-125 b increased after AZC intervention ( P <0. 05 ) . Conclusions ① Hcy promotes vascular smooth mus-cle cell proliferation maybe by down-regulating the ex-pression of miR-125b. ② Hcy down-regulates the ex-pression of miR-125 maybe by up-regulating the methy-lation levels of miR-125b promoter region.

Objective To establish a Goto-Kakizaki ( GK) rat model of duodenal-jejunal bypass( DJB) and ob-serve the changes in insulin-resistance after surgery, and to explore the mechanism of DJB surgery in treatment of type 2 di-abetes mellitus.Methods Male Goto-kakizaki diabetic rats(GK,n=36)were used as experiment group and 18 healthy male Wistar rats as blank group.GK rats were randomly divided into two groups: diabetic control group and DJB surgery group ( n=18) .Euglycemic-hyperinsulinemic clamp technique was performed in 6 rats randomly taken from each group at third week, sixth week and ninth week after surgery, respectively.The expression levels of Gck, G6P, PEPCK mRNA in the liver and GLUT4 content on skeletal muscle cell plasma membrance were detected one week after the clamp test. Results In the DJB surgery group at the end of third week and sixth week after surgery, the levels of glucose infusion rates and the expression levels of Gck, G6P, PEPCK mRNA in the liver showed no statistically significant difference as com-pared with the diabetic control group (P>0.05).In the DJB surgery group at the end of 9th week after surgery, the glu-cose infusion rate and expression level of Gck mRNA in the liver were significantly higher, and the expression of G6P and PEPCK mRNA was significantly lower than those in the diabetic control group ( P<0.05 for all) .At the three time points (3rd week, 6th week and 9th week after surgery), there was no significant difference in the GLUT4 content on skeletal muscle cell plasma membrane between the diabetic control group and DJB surgery group ( P>0.05 for all) .Conclusions Our results indicate that the mechanism of DJB surgery improving blood glucose level may be closely related to the amel-ioration of insulin-resistance in the liver, thereby augmenting glucose uptake and inhibiting gluconeogenesis in liver through the regulation of glucose metabolism-related enzymes.There is no significant improvement in insulin-resistance in the skele-tal muscles during the experiment period.This result implies that the effect of DJB surgery on type 2 diabetes is related to the duration of therapy.

OBJECTIVETo investigate the value of maternal plasma cell-free fetal DNA (cff-DNA) examination in detection of fetal chromosomal aneuploidy in pregnant women at advanced maternal ages during the first trimester of pregnancy.

METHODSA total of 136 pregnant women (11 to 13+6 gestational weeks) with advanced maternal ages were screened for fetal chromosomal aneuploidy with ultrasound and maternal plasma cff-DNA examination during March 1, 2011 to August 31, 2013, and the results were then confirmed by karyotype analysis and fluorescence in situ hybridization (FISH).

RESULTSOf the 136 women examined, cff-DNA screening detected chromosomal aneuploidy in 5 cases, including trisome-21 in 3 cases, trisome-18 in 1 case, and 45,X in 1 case as confirmed subsequently by karyotype analysis. Ultrasound screening reported a normal finding in one case of trisomy-21, thickening of the NT in the case of trisomy-18, and fetal anasarca in the case of 45,X. Karyotype analysis and follow-up of the women did not find chromosomal abnormality in the 131 negative cases screened by cff-DNA detection.

CONCLUSIONScreening of material plasma cff-DNA allows accurate and early detection of fetal chromosomal aneuploidy in women of advanced maternal ages to avoid unnecessary invasive antenatal examinations.

Aneuploidy ; Chromosomes, Human, Pair 18 ; DNA ; blood ; Female ; Humans ; In Situ Hybridization, Fluorescence ; Karyotyping ; Maternal Age ; Pregnancy ; Pregnancy Trimester, First ; Prenatal Diagnosis ; Trisomy

Aim To investigate the possible mecha-nisms of the levels of NO decrease induced apoptosis in human placental trophoblast cells. Methods Human placental trophoblast cells ( HTR-8 ) were cultured in 5 ml DMEM-F12 culture medium with 37℃ 5% CO2 . Then, the old culture medium was discarded and re-placed with 10,100,500,1 000 μmol·L-1 L-NAME, and the group without L-NAME was set as the control group, cultured for 48h. The effects of L-NAME on the survival of cells were detected by methylthiazolyldiphe-nyl tetrazolium bromide ( MTT); the content of NO in cells was tested by nitrate reductive enzymatic;trans-mission electron microscopy, flow cytometry analysis and Annexin-V FITC dyeing were used to test the effects of L-NAME on apoptosis in HTR-8 cells;restore Fe3+ colorimetric assay was applied for detection of to-tal antioxidant capacity ( T-AOC ) , xanthine oxidase for detection of superoxide dismutase ( SOD) activity, and thiobarbituric acid colorimetry for determination of content of MDA. Results Compared with the control group, the survival rate of HTR-8 cells and the levels of NO in 100,500,1 000 μmol·L-1 L-NAME group were significantly reduced(P<0.05,P<0.01). Flow analysis and Annexin-V FITC staining showed that L-NAME could induce cell apoptosis in a dose-dependent manner. The number of cell apoptosis was negatively correlated with the content of NO ( r = -0.5210 ) in HTR-8 cells. Transmission electron microscopy results showed that compared with the control group, the ex-perimental group's cell nucleus shape was irregular, nuclear pyknosis in irregular shape, the chromatin ag-glutination or side the collection, mitochondrial swell-ing or enrichment, crest fracture or dissolved, even vanished, forming the vacuole, especially in 100 μmol ·L-1 L-NAME group, the apoptotic bodies obviously appeared. At the same time, T-AOC, SOD levels in HTR-8 cells decreased ( P <0.05 ) , and the MDA content increased ( P<0.05 ) . The number of cell ap-optosis was negatively correlated with the level of T-AOC ( r= -0.3212 ) , SOD ( r= -0.2779 ) in HTR-8 cells , while positively correlated with the content of MDA(r=0.2807). Conclusion Oxidative stress may play an important role in the levels of NO decrease in-duced apoptosis in human placental trophoblast cells.