斑点核酸杂交技术检测胎儿巨细胞病毒感染的研究

用￣３２Ｐ标记的巨细胞病毒（ＣＭＶ）探针通过斑点核酸杂交技术，对胎盘、脐血及胎儿组织中的ＣＭＶＤＮＡ进行了检测。结果表明，死胎、胎儿畸形的５２份胎盘组织及４８份胎肾组织中ＣＭＶＤＮＡ阳性者分别为４份及５份，正常好妊娠组（早、晚期人耳流产与足月产）的７７份胎盘及３２份胎肾组织中ＣＭＶＤＮＡ均为阴性，同一病例胎盘与胎肾组织中ＣＭＶＤＮＡ均阳性者３例。２例畸形胎儿脐血白细胞中ＣＭＶＤＮＡ阳性者１例，另一例胎儿畸形脑组织及腮腺组织中ＣＭＶＤＮＡ阳性，而正常足月产的２４例脐血白细胞中ＣＭＶＤＮＡ均阴性。共诊断８例胎儿感染ＣＭＶ，正常妊娠组无１例胎儿感染ＣＭＶ，从分子水平上证实ＣＭＶ是致死胎与胎儿畸形的重要病原。     

用聚合酶链式反应技术检测孕妇与胎儿巨细胞病毒感染的研究

应用聚合酶链式反应（ＰＣＲ）技术检测了孕妇、羊水及脐血中巨细胞病毒（ＣＭＶ）ＤＮＡ。结果表明，１８６例中正常孕妇９８例血清中ＣＭＶＤＮＡ阳性２例。阳性率为２％，异常妊娠（死胎、胎儿畸形及产前咨询）孕妇８８例血清中ＣＭＶＤＮＡ阳性１４例，阳性率为１５．９％，两者差异有显著性，（Ｐ＜０．０１）。提示孕妇ＣＭＶ感染与死胎、胎儿畸形及异常妊娠史有关。通过检测羊水和脐血中ＣＭＶＤＮＡ，发现９例胎儿ＣＭＶ感染，其中３例畸形，２例死胎，１例自然流产，３例足月分娩。     

孕妇与胎儿巨细胞病毒感染的研究

目的 :探讨孕妇巨细胞病毒 (CMV)感染 ,早期诊断胎儿CMV感染。方法 :用酶联免疫法 (ELISA)和多聚酶链反应 (PCR)技术检测孕妇血中CMV特异性抗体及CMVDNA ,诊断孕妇CMV感染 ;检测羊水或脐血中CMVDNA诊断胎儿CMV感染。结果 :15 64例孕妇血清中CMV IgM阳性 2 9例 (占 1.8% ) ,CMV IgG阳性 130 6例 (83.5 % ) ,CMVDNA阳性 12 6例 (8.1% ) ;CMV IgM阳性者其CMVDNA均阳性。CMVDNA阳性的 12 6例孕妇其羊水或脐血中CMVDNA阳性 5 2例 (占 4 1.2 % ) ,CMV感染胎儿中有 5例胎儿畸形、2例死胎、3例IUGR ,出生时无明显症状的婴儿中 3例生后 1个月内患黄疸性肝炎 ,1例患新生儿肺炎。 1例发现室间隔缺损、2例出现单侧耳聋。结论 :孕妇CMV感染可造成胎儿严重危害 ,孕妇CMV感染后取羊水或脐血检测CMVDNA是诊断胎儿及新生儿CMV感染的最佳方法。     

孕妇与胎儿巨细胞病毒感染的血清学研究

测定了１７３例孕妇及８１例胎儿血清ＣＭＶ抗体。结果：１７３例孕妇血清中ＣＭＶ－ＩｇＧ阳性率为７０．５％（１２２／１７３），ＣＭＶ－ＩｇＭ阳性率为０．５８％（１／１７３），孕妇早、中、晚孕期ＣＭＶ感染率分别为５２％、７２．９％，７４．４％，妊娠次数≥４次的孕妇ＣＭＶ感染率较高。８１例脐血血清中ＣＭＶ－ＩｇＧ阳性率为５４．３％（４４／８１），ＣＭＶ－ＩｇＭ阳性率为６．２％（５／８１），５例先天性ＣＭＶ感染儿分别为４例胎儿畸形及１例产前咨询者，后者取脐血查到ＩｇＭ阳性后１个月，胎死宫内。提示脐血中一旦查到ＣＭＶ－ＩｇＭ阳性，胎儿有严重后果。因此，产前诊断胎儿ＣＭＶ感染，早期发现ＣＭＶ感染儿，是非常重要的。     

The effect of a reversible period of adverse intrauterine conditions during late gestation on fetal and placental weight and placentome distribution in sheep

Adverse intrauterine conditions occurring during early to mid-gestation or throughout the whole of gestation influence placental weight and the distribution of placentome types in sheep. However, no study to date has investigated the effect of a reversible period of adverse intrauterine conditions during late gestation upon fetal and placental weight and placentome distribution in sheep. Twenty-two sheep fetuses were chronically instrumented with an inflatable cord occluder, amniotic and vascular catheters and with a Transonic flow probe around an umbilical artery. At 125 days (term isca.145 days) the occluder was inflated to reduce umbilical blood flow by ca.30 per cent for 3d in 12 fetuses (umbilical cord compressed, UCC). The occluder was then deflated and umbilical blood flow allowed to return to baseline. The remaining 10 fetuses acted as sham-operated controls in which the occluder remained deflated at all times. At 135-137dGA ewes were humanely killed and tissues collected, weighed and placentomes classified. A reduction in umbilical blood flow by approximately 30 per cent from baseline for 3 days in UCC fetuses led to mild fetal asphyxia throughout the period of cord-compression. After deflation of the occluder cuff, umbilical blood flow returned to a level that was significantly greater than that measured during baseline. Umbilical cord compression had no effect on fetal body weight but significantly increased fetal adrenal weight relative to body weight. While the total number of placentomes was not altered by cord-compression, total placentome weight and the total weight of C/D-type placentomes were both reduced in UCC relative to control placentae. In addition, the mean weight of placentomes, and of C/D-type placentomes specifically, was significantly lower in UCC relative to control placentae. When expressed as a percentage of the total number of placentomes in the placenta, there was a significantly lower percentage of C/D-type placentomes in UCC relative to control placentae. In addition, there was a significant relationship between the total number of placentomes and the percentage C/D-type placentomes in control, but not UCC, placentae. The data suggest that a temporary, reversible period of adverse intrauterine conditions occurring late in gestation in sheep has persisting effects upon the placenta, mean placentome weight and placentome distribution.     

The use of intrapartum fetal blood lactate measurements for the early diagnosis of fetal distress

Lactate concentrations were measured during labor and at delivery in blood samples from the fetal presenting part and from the umbilical cord with the use of a rapid electrochemical technique. The value of these measurements to discriminate between normal and distressed fetuses was compared to that of pH, base excess, Pco₂ and Po₂ measurements in the same blood samples. The fetuses were divided into three groups, normal, prepathologic, and pathologic, according to the presence and severity of fetal distress as evaluated by Apgar score, intrapartum cardiotocography, meconium staining of the amniotic fluid, and cord arterial pH at birth. Lactate and pH provided the best parameters to distinguish between groups, with lactate having the most discriminating power at least in early labor and midlabor. The prospective value of discriminant functions derived from lactate and pH data was good when the fetuses were allocated into the normal group but poor when an attempt was made to allocate the fetuses into prepathologic and pathologic groups, with a high false negative rate. However, the discriminating ability was improved when prepathologic and pathologic fetuses were included into one single abnormal group. These results confirm the potential use of rapid fetal blood lactate measurements for the early diagnosis of intrapartum fetal distress.     

Reliability of fetal buttock blood sampling in assessing the acid-base balance of the breech fetus

This prospective investigation was undertaken to compare fetal buttock capillary blood pH and umbilical artery and vein pH in fetuses presenting by the breech. The study group comprised ten term patients with singleton fetuses in the frank breech presentation who met established criteria for vaginal breech delivery. All patients had a normal labor pattern. Eight fetuses had a normal fetal heart rate tracing and two had severe variable decelerations during the second stage of labor. We obtained capillary blood for pH measurement from the fetal buttock within 15 minutes of delivery. Immediately after delivery, we collected arterial and venous blood samples from the umbilical cord for measurement of pH. In all fetuses, there was a highly significant correlation between fetal buttock capillary blood pH and umbilical artery pH (r = 0.96; P less than .001) and umbilical vein pH (r = 0.88; P less than .001). We conclude that measurement of pH in capillary blood obtained from the fetal buttock provides accurate assessment of the acid-base status of the breech fetus.     

Increase in 3-methylhistidine in umbilical cord blood from acidotic fetuses

OBJECTIVE: To examine the hypothesis that acidotic fetuses at birth have an increased catabolic state characterized by a negative nitrogen balance. STUDY DESIGN: Umbilical cord blood samples were obtained from a random, prospective series of fetuses at birth. Acidotic samples (pH < 7.20) were matched with normals (pH > or = 7.20) according to maternal and gestational age. 3-Methylhistidine was analyzed in order to assess catabolic breakdown of muscle protein. RESULTS: 3-Methylhistidine was significantly increased (P < .05) in cord blood from acidotic fetuses when compared with controls and correlated negatively (P < .05) with umbilical arterial pH. CONCLUSION: Umbilical cord blood 3-methylhistidine may be used to assess fetal nitrogen balance; acidotic fetuses have increased muscle catabolism.     

正常晚期妊娠胎儿脐动脉,大脑中动脉及腹主动脉血流速度波形与？…

目的 探讨正常妊娠胎儿血流速度波形与胎儿血气的相关性,方法 应用彩色多普勒超声对４５例正常晚期妊娠初孕妇女于剖宫产术时２４小时内进行胎儿脐动脉（ＵＡ）,大脑中动脉（ＭＣＡ）及腹主动脉（ＡｂＡｏ）的血流速度波形（ＦＶＷｓ）检查,计算搏动指数（ＰＩ）,阻力指数（ＲＩ）及收缩期最大血流速度（Ｓ）与舒张末期血流速度（Ｄ）的比值（Ｓ／Ｄ）,同时对剖宫产分娩的新生称立即进行脐动脉血气ｐＨ,二氧化碳分压（ＰＣＯ     

正常晚期妊娠胎儿脐动脉、大脑中动脉及腹主动脉血流速度波形与胎儿血气相关性探讨

目的探讨正常妊娠胎儿血流速度波形与胎儿血气的相关性。方法应用彩色多普勒超声对４５例正常晚期妊娠初孕妇女于剖宫产术前２４小时内进行胎儿脐动脉（ＵＡ）、大脑中动脉（ＭＣＡ）及腹主动脉（ＡｂＡｏ）的血流速度波形（ＦＶＷｓ）检查，计算搏动指数（ＰＩ）、阻力指数（ＲＩ）及收缩期最大血流速度（Ｓ）与舒张末期血流速度（Ｄ）的比值（Ｓ／Ｄ），同时对剖宫产分娩的新生儿立即进行脐动脉血气ｐＨ、二氧化碳分压（ＰＣＯ２）、氧分压（ＰＯ２）测定。结果ＵＡＲＩ与血ｐＨ、ＰＯ２呈明显负相关（Ｐ＜０．０１，Ｐ＜０．０５），与ＰＣＯ２呈正相关（Ｐ＜０．０５），ＭＣＡＲＩ与血ｐＨ、ＰＯ２呈明显正相关（Ｐ＜０．０１，Ｐ＜０．０５），与ＰＣＯ２呈负相关（Ｐ＜０．０５）。结论产前监测ＵＡ及ＭＣＡ的血流速度波形，可间接了解胎儿血气情况，及时判断胎儿宫内安危的状况。     

Evaluation of the clinical usefulness of isolation of fetal DNA from the maternal circulation

OBJECTIVE: To assess the reliability of isolating free fetal DNA from maternal usefulness. DESIGN: Fetal DNA was isolated from plasma or serum that was either collected prospectively or from archived samples collected for the purposes of second trimester screening. METHODS: Prospective samples were collected from patients undergoing prenatal diagnostic procedures (n = 24). A second group of samples from Rhesus negative women (n = 28) were assayed in which blood had originally been collected for maternal triple serum screening. DNA was extracted from all samples and assayed for the presence of the beta-globin gene, sex-determing region Y (SRY) gene and Rh gene. All DNA sample handling and extraction was carried out by a single operator, and polymerase chain reaction (PCR) was carried out using previously published PCR primers and appropriate controls. The accuracy of results was assessed relative to the karyotype in the case of the SRY gene or cord blood phenotype in the case of the Rh gene. RESULTS: The SRY PCR results were compared to fetal cell karyotypes obtained from invasive diagnostic testing, 21 out of the 24 samples were correctly 'sexed'. The RhD PCR results were compared to fetal cord blood samples at the time of delivery, and showed both false positive and false negative results. Two RhD negative babies were genotyped as RhD positive, despite repeat analysis. CONCLUSION: It is possible to isolate fetal DNA from maternal serum. It is a potentially clinically useful technique in our laboratory and can be used to detect male fetuses, and Rh negative fetuses. To be useful in clinical practice, it is necessary to safeguard against contamination at the time of sample handling, and to use the optimal range of primers available to cover the polymorphisms present within the RhD gene. Although not robust enough yet to be used with diagnostic certainty in our hands, immense improvements in technique, probes and real-time PCR equipment make this type of diagnosis a reality in the near future.     

Study of intrauterine cytomegaloviruses infection in pregnant women and fetuses

Detection of cytomegaloviruses (CMV) DNA in urine samples from pregnant women and newborns' cord blood was done by DNA-DNA hybridization. 33.3% of pregnant women showed CMV DNA sequences in the 1-3 months, 36.4% in the 4-6 months and 38.2% in the 7-9 months. The results suggested that the CMV infection rate of pregnant women increased as time went on.75.0% women with history of abnormal pregnancies showed CMV in their urine and 30.4% newborns' cord blood was positive for CMV. It is apparently that CMV infection rate in women with history of abnormal pregnancies was much higher than that of normal pregnant women and the danger of miscarriage in pregnant women with primary CMV infection at early pregnancy increased. CMV congenital infection rate was also high in newborns.     

应用荧光定量聚合酶链反应技术诊断胎儿弓形虫感染

目的　探讨荧光定量聚合酶链反应 (FQ PCR )技术用于产前诊断胎儿弓形虫 (TOX)感染及其防治措施。方法　采用FQ PCR技术 ,检测 70例孕期TOXDNA阳性孕妇的羊水和 (或 )脐血的TOXDNA ,阳性者为胎儿TOX感染。对其中 48例TOX感染孕妇给予螺旋霉素常规剂量治疗 2个疗程 ,观察其治疗效果。结果　 (1) 70例TOXDNA阳性孕妇中 ,胎儿TOXDNA阳性 2 1例 ,胎儿宫内TOX感染率为 3 0 % ,羊水和脐血中的TOXDNA阴、阳性结果一致。 (2 )胎儿宫内TOX感染与孕妇血中TOXDNA含量高低有关 ,孕妇血中TOXDNA含量高时 ,对胎儿危害严重 ,胎儿宫内感染率也最高(5 5 % ) ;TOXDNA含量低时 ,胎儿宫内感染率也最低 (2 0 % ) ,两者比较 ,差异有显著性 (P <0 0 5 )。 (3 )经螺旋霉素治疗的孕妇 ,其胎儿宫内感染率为 2 1% ,明显低于未治疗者的 5 0 % ,两者比较 ,差异有显著性 (P <0 0 5 )。结论　孕妇TOX感染可危害胎儿 ,FQ PCR检测羊水中TOXDNA可准确地诊断胎儿TOX感染 ,孕期治疗可降低宫内TOX感染率     

A study on cytomegalovirus infection in 199 pregnant women and their infants

Cytomegalovirus (CMV) infection is common in human, and exerts harmful effects during pregnancy upon fetuses. In order to get a clear knowledge of CMV infection rate in pregnant women and their infants and of the relationship between maternal infection and congenital infection in our city, we tried to detect the CMV specific IgG and IgM in 199 paired serum samples of mother and infant. The results showed that 183 maternal serum samples and 179 umbilical cord serum samples were CMV-IgG positive, a positive rate of 92% and 90% respectively. While 6 maternal serum samples and 7 umbilical cord serum sample were CMV-IgM positive, a positive rate of 3.0% and 3.5% respectively. The close correlation of CMV-IgM levels between mothers and their babies indicates that the infant may acquire congenital infection from his CMV-IgM positive mother.     

Phasic blood flow patterns in the common umbilical vein of fetal sheep during umbilical cord occlusion and the influence of autonomic nervous system blockade

The blood flow pattern in the common umbilical vein is under normal conditions nonpulsatile in contrast to the flow in the fetal inferior vena cava. We observed pulsatile flow patterns in the common umbilical vein of fetal lambs during changes in the fetal hemodynamic equilibrium. These pulsations may influence the mixing of oxygen-rich ductus venosus blood and oxygen-poor inferior vena cava blood. This study deals with the phasic changes in umbilical venous blood flow during cord occlusion. The experiments were performed in eight chronically instrumented fetal lambs between 114 and 133 days gestation (term 146 days). Umbilical venous blood flow was measured with an electromagnetic flow transducer around the intraabdominal common part of both umbilical veins. The fetuses were provided with catheter in the fetal abdominal aorta and with electrodes for monitoring arterial blood pressure and heart rate. Occlusion of the umbilical cord was performed by means of an inflatable balloon occluder around the total cord (occlusion time 20 to 90 seconds). Occlusions were performed in fetuses with an intact autonomic nervous system and after blockade of the alpha-adrenergic, beta-adrenergic or cholinergic part of the autonomic nervous system.     

Identification of kynurenine pathway enzyme mRNAs and metabolites in human placenta: up-regulation by inflammatory stimuli and with clinical infection

OBJECTIVE: The purpose of this study was to determine whether placental-derived kynurenines (neuroactive metabolites that are derived from tryptophan) contributes to infection-mediated fetal cerebral injury. STUDY DESIGN: Placentae and cord blood were obtained from term deliveries (n = 16) and preterm deliveries with or without intrauterine bacterial infection (n = 8 per group). We investigated whether the placenta expressed messenger RNAs of kynurenine metabolite-forming enzymes, the effects of infection in vivo on the expression of these enzymes by the placenta, the in vitro effects of bacterial endotoxin lipopolysaccharide on expression and kynurenine metabolite output by the placenta, and the kynurenine metabolite levels in umbilical cord blood. RESULTS: Placentae expressed messenger RNA of tryptophan-degrading enzymes and synthesized several compounds. The expression of several enzymes increased significantly in placentae that were exposed to infection and/or lipopolysaccharide. Lipopolysaccharide also induced significant increases in placental kynurenine and quinolinic acid output. Kynurenine and quinolinic acid in cord blood of fetuses who were exposed to infection were elevated significantly. CONCLUSION: Inflammatory mediated release of kynurenines from placentae exposes the fetus to significant amounts of potentially neurotoxic substances.     

The PR interval-fetal heart rate relationship during repetitive umbilical cord occlusions in immature fetal sheep

OBJECTIVE: To evaluate the relationship of the PR interval and fetal heart rate during repetitive umbilical cord occlusions in immature sheep fetuses. STUDY DESIGN: In seven chronically cannulated immature sheep fetuses [gestational age 90.6 days (mean)], we analyzed continuous fetal electrocardiogram recordings during repetitive cord occlusions for 2 out of every 5 min until fetal mean arterial pressure dropped to 50% of baseline value. PR interval-fetal heart rate correlation coefficients (Pearson) was measured on consecutive blocks of 2.5 min. R-values of the baseline and the repetitive occlusion period were compared by Fisher's exact test. RESULTS: Repetitive cord occlusions resulted in acidosis and hypotension. Two fetuses died at the end of the repetitive occlusion period. Four out of seven fetuses showed a significant change from a negative relationship between the PR interval and fetal heart rate during baseline to a predominantly positive relationship during the repetitive occlusion period. CONCLUSION: In immature fetal sheep, a change from a negative relationship between the PR interval and fetal heart rate to a predominantly positive relationship between the PR interval and fetal heart rate was observed in four out of seven fetuses following the initiation of repetitive umbilical cord occlusions.     

Cord sampling for the evaluation of oxygenation and acid-base balance in growth-retarded human fetuses

In 14 pregnancies complicated by intrauterine growth retardation, the umbilical cord was sampled before delivery under ultrasonic guidance for rapid fetal karyotyping. Fetal blood was analyzed for respiratory gases, acid-base balance, and lactate concentrations. Two patients were excluded from the study because cord samples were diluted with amniotic fluid. In six patients (group 1), the clinical assessment warranted continuation of pregnancy. Cesarean sections were performed in the remaining eight patients (group 2) within 8 hours of cord sampling. The data from the two groups were compared with those obtained from umbilical venous blood at the time of elective repeat cesarean section in term appropriate for gestational age infants (controls). No significant difference in PO2 was found between groups 1 and 2 and controls. In contrast, there were significant differences in oxygen saturation and acid-base balance between groups 1 and 2. Lactate concentration was inversely correlated with pH and was elevated in five of six fetuses requiring a prompt cesarean section: In two of these five fetuses, nonstress fetal heart rate tracings were reactive. The results suggest that fetal blood biochemistry, and particularly lactate concentration, may represent an additional indicator of fetal well-being in pregnancies complicated by intrauterine growth retardation.     

Fetoscopy in the assessment of unexplained fetal hydrops

Pure fetal blood samples, obtained fetoscopically from 30 patients with unexplained fetal hydrops at 16 to 32 weeks gestation were investigated for cytogenetic, haematological, biochemical and virological properties. In two patients with oligohydramnios, the fetoscope was introduced transabdominally into the fetal peritoneal cavity and sampling was undertaken from the intra-abdominal portion of the umbilical vein; in all the other patients an umbilical cord vessel was sampled. Ten (33%) of the fetuses had chromosomal abnormalities, one an erythroblastic process, possibly erythroleukaemia, one alpha-thalassaemia and one cytomegalovirus infection. Blood-film abnormalities were seen in 23 (88%) of 26 fetuses that had this examination. Biochemical analysis of fetal plasma was undertaken in 18 fetuses and hypoproteinaemia was found in all cases. One fetus was subsequently found to have a paroxysmal tachyarrhythmia that responded to digitilization. Three (10%) of the fetuses survived.     

Fetoscopy in the assessment of unexplained fetal hydrops

Summary. Pure fetal blood samples, obtained fetoscopically from 30 patients with unexplained fetal hydrops at 16 to 32 weeks gestation were investigated for cytogenetic, haematological, biochemical and virological properties. In two patients with oligohydramnios, the fetoscope was introduced transabdominally into the fetal peritoneal cavity and sampling was undertaken from the intra-abdominal portion of the umbilical vein; in all the other patients an umbilical cord vessel was sampled. Ten (33%) of the fetuses had chromosomal abnormalities, one an erythroblastic process, possibly erythroleukaemia, one α-thalassaemia and one cytomegalovirus infection. Blood-film abnormalities were seen in 23 (88%) of 26 fetuses that had this examination. Biochemical analysis of fetal plasma was undertaken in 18 fetuses and hypoproteinaemia was found in all cases. One fetus was subsequently found to have a paroxysmal tachyarrhythmia that responded to digitilization. Three (10%) of the fetuses survived.