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B Brambati

Publications and source records attributed to B Brambati.

At least 19 recordsLinked to original sources
PubMed1992

First-trimester prenatal diagnosis of Roberts syndrome.

We present a case of prenatal detection of premature centromere separation on chorionic villi sampled at 8 weeks' gestation from a woman at risk of recurrence of Roberts syndrome. The same cytogenetic characteristic was confirmed on amniocytes at 14 weeks when ultrasound examination showed morphological anomalies of the fetus. To our knowledge, this is the first report of early prenatal diagnosis of Roberts syndrome.

Abnormalities, Multiple↗
PubMed1992

Genetic diagnosis by chorionic villus sampling before 8 gestational weeks: efficiency, reliability, and risks on 317 completed pregnancies.

Transabdominal chorionic villus sampling (TA-CVS) was attempted in 328 high-risk pregnancies at 6-7 weeks of gestation. Sampling was feasible in 97.7 per cent of cases; chorionic tissue specimens of more than 10 mg were obtained in 94.4 per cent of cases at the first needle insertion and in 100 per cent after a second attempt. Fetal karyotyping succeeded in 99.4 per cent of cases, while no diagnostic failures were reported in enzymatic and DNA analyses. Fetal loss rate in the first 4 weeks after CVS was significantly higher than in the later CVS series (7.2 vs. 2.5 per cent), but 50 per cent of losses were observed within 2 weeks in cases of inviable aneuploidies. A high incidence of severe limb abnormalities (1.6 per cent) was detected in pregnancies intended to continue, confirming the aetiological role of early CVS. Unclear visualization of the placental limits and poor control of the needle path are thought to be the main reasons for the vascular disruption of the chorionic plate, and thereby hypoxic embryo tissue damage. A better selection of cases, together with high-resolution vaginal ultrasound visualization, and analytical techniques requiring a minimal amount of tissue should avoid any teratogenic effect of early CVS.

Adult↗
PubMed1992

Prenatal diagnosis of metabolic diseases on chorionic villi obtained before the ninth week of pregnancy.

Nine pregnancies at risk for various metabolic disorders were monitored by prenatal diagnosis on chorionic villi obtained between the sixth and ninth weeks of pregnancy. A diagnosis of an affected fetus was made in five cases (Sandhoff, Tay-Sachs (2), Pompe's, GM1), while metachromatic leukodystrophy, GM1 (2), and Pompe's were excluded in four cases. It is concluded that chorionic villi are a reliable tissue for prenatal diagnosis of metabolic disorders also when obtained before the ninth week.

Cerebroside-Sulfatase↗
PubMed1992

Extravillus dividing fetal cells at CVS: evidence of their erythroblastic origin.

Cytological and cytogenetic studies were performed on nucleated fetal cells present in chorionic villus transport medium. The erythroblastic origin of these cells was shown. Fetal erythroblasts in spontaneous mitosis were frequently observed; chromosome counts were obtained from them but poor quality often prevented banded analysis. Cytogenetic study of erythroblast metaphases can be useful as an additional diagnostic aid in cases of mosaicism with aneuploid cell lines.

Amniotic Fluid↗
PubMed1992

Trisomy 16 confined to chorionic villi and unfavourable outcome of pregnancy.

Two cases of trisomy 16 confined to placental tissue associated with an unfavourable outcome of the pregnancy are reported. In the first case, after a diagnosis of an apparent non-mosaic trisomy 16 at chorionic villi sample (CVS), an intrauterine fetal death occurred at the 22nd week. In the second case a mosaic with trisomy 16 was found in chorionic villi and the fetus was still-born at 38 weeks. From a comparison of their cases with those of the literature, the authors conclude that a trisomy 16 confined to placental tissue has a negative effect on fetal growth and pregnancy outcome.

Adult↗
PubMed1991

Randomized clinical trial of transabdominal versus transcervical chorionic villus sampling methods.

The relative advantages and disadvantages of transabdominal (TA) and transcervical (TC) chorionic villus sampling (CVS) in terms of fetal risks and efficacy were evaluated in a clinical trial conducted on 1194 women randomized at 7-12 weeks' gestation. The results of the study indicate that, if any, the relative risk of fetal loss following either procedure is less than double that of the alternative technique when performed by a skilled operator. Overall, the fetal loss rate (spontaneous abortions following randomization, terminations of pregnancy, and perinatal deaths) is 16.5 and 15.5 per cent, respectively, among women allocated to TA- and TC-CVS. The two procedures are equally effective, although TA-CVS is associated with a significantly lower rate of repeat device insertions; on the other hand, a higher weight of chorionic tissue is obtained, on average, with TC-CVS. Bleeding is more common following TC-CVS, while peritoneal reaction developed only after TA-CVS. No diagnostic problems specifically related to one sampling technique were identified.

Birth Weight↗
PubMed1991

Prenatal paternity testing by DNA analysis.

Prenatal paternity testing was evaluated by DNA analysis in chorionic villus biopsies obtained during the 7th-22nd weeks of gestation. Using highly polymorphic variable number of tandem repeats (VNTR) probes, we analysed four cases consisting of mother/child/alleged father trios. In all cases, we were able to detect maternal and paternal alleles and could establish or exclude paternity. The application of DNA analysis represents a new important diagnostic aid for all cases that require a prenatal identification of paternity.

Blotting, Southern↗
PubMed1991

First-trimester genetic diagnosis in multiple pregnancy: principles and potential pitfalls.

Both the principles of first-trimester genetic diagnosis in multiple pregnancy and the special considerations required to avoid potential diagnostic pitfalls are presented. The experience consisted of 65 cases of twins and one case of quadruplets. Dichorionic twins were recognized by sonography in 54 cases. Transabdominal aspiration was generally preferred to transcervical for obtaining chorionic tissue, although in two cases both approaches were used. Diagnostic error following erroneous sampling was reported in 3 out of 54 sets of dichorionic twins (5.5 per cent). When like-sex dichorionic twins cannot be differentiated by cytogenetic or DNA polymorphism studies, amniocentesis should be recommended to confirm the reliability of the result on chorionic tissue.

Adult↗
PubMed1991

Genetic diagnosis before the eighth gestational week.

Transabdominal chorionic villus sampling (CVS) by a freehand, ultrasound-guided technique was offered to 210 high-genetic-risk women at 6-7 weeks' gestation. It was carried out in 201 cases and postponed in nine cases (4.3%). Sampling was successful in 86 and 100% of cases after the first and the second needle insertions, respectively. Chorionic tissue specimens weighed at least 20 mg in 86% of cases, and only 2% were below 10 mg. Early complications were present in 7.9% of cases, apparently without any adverse effect on maternal or fetal outcome. The rate of fetal loss was 3.5%. Genetic diagnosis was concluded in 1-3 days by rapid diagnostic methods. Although more extensive laboratory and clinical experience is necessary to evaluate adequately the safety of early transabdominal CVS, it may be advantageous to offer this technique to certain high-genetic-risk patients. The availability of genetic diagnosis before the eighth week makes clinical abortion by antiprogestins and prostaglandins a viable option in cases of affected embryos.

Adult↗
PubMed1990

Transabdominal and transcervical chorionic villus sampling: efficiency and risk evaluation of 2,411 cases.

Efficacy and risks of transcervical and transabdominal chorionic villus sampling (CVS) methods were evaluated in 1,501 and 910 cases, respectively. We reported a success rate of more than 99% for both sampling procedures and obtained an adequate amount of chorionic tissue in more than 96% of cases on the first attempt. However, the transcervical method was more difficult to learn and was contraindicated by a higher number of unfavorable clinical and anatomical conditions. Transabdominal sampling proved to be a less time-consuming procedure and could also be used after the 12th week of gestation. Bleeding/spotting (10.1%) and uterine cramping (2.5%) were the most frequent early complications following transcervical and transabdominal sampling, respectively. Uterine infection was rare (0.13%) and was reported only after cervical aspiration. No significant effects on fetal growth, preterm delivery, placenta disorders, congenital defects, and perinatal mortality following transcervical and transabdominal sampling, and for both procedures total fetal loss rate was less than 4%. This experience suggests that transabdominal needle sampling is the method of choice; however, transcervical aspiration appears more likely to succeed in a limited number of well-defined conditions.

Chorionic Villi Sampling↗
PubMed1990

Abnormal maternal serum levels of human chorionic gonadotropin free subunits in trisomy 18.

We have measured maternal serum levels of free alpha and beta subunits of human chorionic gonadotropin between 8 and 12 weeks of gestation in 704 women at increased risk for trisomy. This group was studied because of advanced maternal age or a previous birth with chromosomal abnormality. All sera had been collected prior to chorion villus biopsy for prenatal diagnosis. Serum levels of free alpha and beta hCG were determined by specific monoclonal antibody-based immunoradiometric assays. Analysis of chorionic tissue showed that in 38 of 704 (5.4%) pregnancies the fetus had a chromosome abnormality. There were 8 fetuses with trisomy 18 (1.1%) and 9 (1.3%) with trisomy 21. In all pregnancies carrying a trisomy 18 fetus, we observed either high levels of free alpha hCG or low levels of free beta hCG or both. More importantly, the calculated ratio of free beta hCG/alpha hCG was less than 0.25 multiples of the median (MoM) in 6 of 8 (75%) trisomy 18 cases. Only 21 of 666 mothers (3.2%) carrying a normal fetus had a ratio less than 0.25 MoM (P less than 0.0001). There was no difference between this ratio in trisomy 21 and normal pregnancy. Thus, when adjusted for gestational age, a low free beta hCG/alpha hCG ratio in maternal serum indicates a pregnancy at high risk [RR = 72 (95% CI 32, 162)] for trisomy 18.

Chorionic Gonadotropin↗
PubMed1990

Sister chromatid exchanges in first-trimester chorionic villi after in vivo and in vitro exposure to diagnostic ultrasound.

A study was done to evaluate the effects of diagnostic ultrasound on sister chromatid exchange (SCE) in first-trimester chorionic villi under controlled technical conditions. Chromosome analysis was performed by the direct method using spontaneous mitoses from the cytotrophoblast layer, and SCE visualization was accomplished by a 72 h treatment with 5-bromodeoxyuridine (BrdU) at a concentration of 10 micrograms/ml. The slides were stained with acridine orange. Immediately before first-trimester chorionic villus sampling, a group of ten pregnant women was exposed to diagnostic ultrasound for 20 min (in vivo exposure). This group of patients was compared with a control group who were not exposed. A mean value of SCE/cell frequency of 4.2 +/- 0.2 was found in the exposed pregnancies, while a value of 3.7 +/- 0.2 was observed in the control group. After in vitro exposure of chorionic villi obtained from elective abortions, the frequency of SCE/cell did not differ significantly among samples with different exposures (1, 2, and 3 h) and controls. The positive control (mitomycin C) yielded a significant increase in SCE frequency.

Chorionic Villi↗
PubMed1990

First-trimester maternal serum alpha-fetoprotein and human chorionic gonadotropin screening for chromosome defects.

The aim of this study was to determine the efficacy of combined maternal serum alpha-fetoprotein (MSAFP) and maternal serum human chorionic gonadotropin (MShCG) screening in detecting chromosome defects in the first trimester of pregnancy. Sera of 492 women (previously assayed for MSAFP) were analysed for MShCG under code without knowledge of cytogenetic results. Overall, 48 of 492 patients (9.8 per cent) had either an MSAFP multiple of the median less than or equal to 0.5 or an MShCG beta/alpha ratio multiple of the median less than or equal to 0.25, eight of whom had a fetus with a serious chromosome defect. A third of fetuses with Down's syndrome and 83 per cent with trisomy 18 were detected at a potential 'cost' of providing chorionic villus sampling or amniocentesis in 8.6 per cent of women screened.

Adult↗