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J L Simpson

Publications and source records attributed to J L Simpson.

At least 181 records · Page 10Linked to original sources
PubMed1986

Maternal serum alpha-fetoprotein screening: low and high values for detection of genetic abnormalities.

In initiating a maternal serum alpha-fetoprotein screening program, we pursued not only elevated values for the detection of neural tube defects but also low values to detect trisomic fetuses. We detected neural tube defects (0.2%) as expected but were surprised by the efficacy with which low serum alpha-fetoprotein values identified aneuploid fetuses. In 1421 pregnant women, 132 (9.3%) showed maternal serum alpha-fetoprotein values less than 0.4 multiple of the median. After repeat sampling, 57 women still had low values. These 57 women and six others who were too anxious for repeat sampling underwent level I ultrasound examination with the following results: gestational age overestimated by 2 weeks (n = 8), fetal death (n = 1), and no explanation (n = 54). Of the 54, 49 underwent amniocentesis with detection of three aneuploid fetuses: trisomy 18 (n = 2) and trisomy 21 (n = 1); maternal ages were 27, 29, and 31 years, respectively. Autosomal aneuploidy did not occur in other women screened. We conclude that low maternal serum alpha-fetoprotein values could efficiently detect aneuploid fetuses, perhaps with greater sensitivity than previously predicted.

Adult↗
PubMed1986

Chorionic villus sampling in continuing pregnancies. I. Low fetal loss rates in initial 109 cases.

Among the first 150 women who agreed to have chorionic villus sampling after receiving counseling and giving informed consent, 41 proved ineligible. In six (5.5%) of the remaining 109 cases in which chorionic villus sampling was performed, we were unsuccessful in obtaining an adequate amount of villi to permit diagnostic testing. In the single loss, fetal viability was confirmed 2 weeks after sampling; however, fetal death became evident 3 weeks later. In four (3.7%) cases the pregnancies were terminated because of abnormal results, and in one (0.9%) case the pregnancy was electively terminated after normal results. Among the 41 completed pregnancies no anomalies were evident in the infants. There were two premature deliveries; one of these two infants died shortly after birth following premature rupture of the membranes at 29 weeks' gestation. All undelivered cases were progressing normally at the time of submission.

Abortion, Induced↗
PubMed1986

Chorionic villus sampling in continuing pregnancies. II. Cytogenetic reliability.

Cytogenetic analysis was performed on 103 chorionic villus samples. Analysis of the 103 samples revealed six abnormalities. In three of the six the abnormalities were confirmed in fetal or neonatal tissue (47,XY, + 13; 46,XY, t(13q13q); 45,X). In three samples the abnormalities detected were not confirmed; in two of the three the abnormalities were detected only in long-term cultures, whereas in the other samples the abnormality was restricted to direct analysis of the villi after overnight incubation. Our initial experience leads us to conclude that certain abnormalities in chorionic villus sampling may not be indicative of fetal abnormalities; 45,X/46,XX or 45,X/46,XY mosaicism is such a complement. Discrepancies between cytogenetic analysis of intact villi processed soon after sampling and of cells grown in culture can be managed by adhering to several suggested guidelines and by liberal use of confirmatory amniocentesis.

Amniocentesis↗
PubMed1986

Gestational diabetes mellitus: a syndrome with phenotypic and genotypic heterogeneity.

One hundred ninety-nine gravida with gestational diabetes mellitus (GDM) defined as "carbohydrate intolerance of varying severity with onset or first recognition during pregnancy" have been stratified into subgroups on the basis of fasting plasma glucose and evaluated for further phenotypic and genotypic heterogeneity. A significantly greater proportion of the women in all our groups were older and heavier than in a "control" population of 148 consecutive gravida with documented normal oral glucose tolerance. After correction for age and weight by covariate analysis, absolute insulinopenia in response to oral glucose could be demonstrated in all GDM groups, although exceptions were present in each. The incidence of diabetes in the mothers of our patients with GDM was 8-fold greater than in controls; the incidence in fathers did not deviate from control patterns. HLA-DR3 and DR4 antigens were more frequently present in GDM and the increase was statistically significant in blacks. At the time of diagnosis, cytoplasmic islet cell antibodies (ICA) were significantly more common in GDM associated with elevated fasting plasma glucose than in controls; the frequency of ICA was 18.4% (7/38) in women with fasting plasma glucose greater than or equal to 130 mg/dl. Our findings indicate that GDM entails genotypic as well as phenotypic diversity and may include patients with slowly-evolving Type I diabetes mellitus, as well as patients with Type II diabetes mellitus, and women with asymptomatic diabetes which antedated the pregnancy (i.e. pregestational diabetes mellitus). Appreciation of this heterogeneity should be incorporated into any evaluation of intervention strategies for women with GDM or into prognoses concerning their postpartum metabolic status.

Adult↗
PubMed1986

Ultrasonic assessment of fetal response to second-trimester amniocentesis.

Twenty-three patients undergoing second-trimester amniocentesis were ultrasonically monitored for 30 minutes before and 30 minutes after the amniocentesis. Fetal movements were recorded as movements of limbs, trunk, or combined limb-trunk movements. Fetal heart rates were determined at ten-minute intervals before and after the amniocentesis. No significant increase in total fetal movements, limb movements, trunk movements, or heart rate were found. A significant increase in combined fetal movements was observed. The authors conclude that amniocentesis in the second trimester elicits a change in fetal movement pattern.

Adult↗
PubMed1986

Hypermodal cells, hypomodal cells, and repetitive abortions.

The frequency of neither hypermodal cells (2N = 47) nor hypomodal cells (2N = 45) differed between lymphocytes of individuals experiencing repetitive spontaneous abortions (N = 429) and controls (N = 90). The same conclusion held when data were analyzed according to chromosome involved (sex chromosome, autosome) or other variables (e.g., prior reproductive outcome). A study of this relatively large sample failed to confirm findings of smaller and sometimes uncontrolled studies. Hypermodal cells do not necessarily serve as a clue to meiotic instability and in turn probably do not identify couples at risk for recurrent aneuploidy.

Abortion, Habitual↗
PubMed1985

Predictive value, sensitivity, and specificity of ultrasonic targeted imaging for fetal anomalies in gravid women at high risk for birth defects.

In this report the predictive value of ultrasonic targeted imaging for fetal anomalies (TIFFA) is defined. Six hundred fifteen pregnant women at high risk for birth defects were scanned from January, 1980, to December, 1983. Follow-up evaluation was available on 569 fetuses. The pregnancies were classified into five groups according to the indications used for ultrasonic targeted imaging studies. The largest number of women were placed in group 1 and were referred because of a variety of abnormalities in previous or ongoing pregnancies. The women classified in the other four groups were examined because of maternal or fetal reasons related to specific craniospinal (29%), urinary (7.9%), gastrointestinal (6.7%), and skeletal (3.7%) defects. In our series the predictive values of abnormal and normal ultrasonic targeted imaging studies were 95% and 99%, respectively. A detailed breakdown of the accuracy of ultrasonic targeted imaging in relation to each anatomic category is presented; these data are useful in counseling gravid women with anomalous fetuses.

Congenital Abnormalities↗
PubMed1985

Chorionic villus sampling for first-trimester prenatal diagnosis: Northwestern University program.

We present our initial experience in developing a chorionic villus sampling program at Northwestern University. In phase 1, we performed chorionic villus sampling in 58 patients prior to elective first-trimester abortion, assessing the reliability and reproducibility of obtaining adequate villus samples and performing cytogenetic analysis by means of both the direct and culture methods. Specimens were categorized according to quality: class I, multiple identifiable villi (n = 20); class II, few villi or villi mixed with decidua (n = 15); class III, no villi (n = 23). There was a positive trend between operator experience, amount of villi obtained, and quality of cytogenetic preparations. In March, 1984, we received Institutional Review Board approval to perform chorionic villus sampling in continuing pregnancies (phase 2). Among the first 20 cases we found two abnormalities (47,XY, + 13; 45,X). The remaining 18 pregnancies were continuing. Recommendations are made for developing a chorionic villus sampling program.

Adolescent↗
PubMed1985

Frequency of diabetes mellitus in mothers of probands with gestational diabetes: possible maternal influence on the predisposition to gestational diabetes.

Interviews for genetic histories were conducted prior to delivery in 166 pregnant diabetic probands and 83 control gravidas with normal carbohydrate metabolism throughout gestation. A significant association was observed between parental diabetic phenotypes and type of diabetes in the probands (chi 2(12)) = 32.413; p less than 0.001). In particular a higher than expected number of mothers with diabetes was encountered in 91 probands with gestational diabetes mellitus. The findings are examined in relationship to the hypothesis that vulnerability to gestational diabetes may be increased by exposure to an abnormal environment during intrauterine development.

Adult↗
PubMed1985

Adverse effects of human leukocyte antigen-DR sharing on fertility: a cohort study in a human isolate.

To elucidate further the reproductive effects of human leukocyte antigen (HLA) sharing among spouses, we have been investigating prospectively the relationship between HLA-A, -B, and -DR sharing and reproductive outcome in the Hutterites, a religious isolate that proscribes contraception. For the first time the reproductive effects of HLA-DR sharing in a fertile population is reported in this article. Median intervals from marriage to first through fifth births were longer among couples who shared more than one HLA-A, -B, or -DR antigen. Longer intervals were associated with increased spontaneous abortion rates among couples who shared HLA-DR antigens (27%), compared with couples who shared only HLA-A or -B antigens (9%) and couples who shared no antigens (12%). Median completed family sizes were 5.0, 8.5, and 8.0 among the groups, respectively. However, some couples who shared HLA-DR antigens experienced no spontaneous abortions, despite ten or more pregnancies. Therefore, although HLA-DR compatibility, per se, is not deleterious, our data suggest a potentially important role for undefined HLA-linked genes in normal pregnancy.

Abortion, Spontaneous↗
PubMed1984

Sister chromatid exchanges after exposure to ultrasound and mitomycin C.

A pilot study was designed to determine whether a synergistic ability to produce sister chromatid exchanges exists between ultrasound and mitomycin C, an alkylating agent known to induce sister chromatid exchanges. Bromodeoxyuridine-containing cells from human lymphocyte cultures were randomized into one of four exposures: (1) unexposed controls, (2) 20 minutes of pulsed ultrasound (3.5 MHZ), (3) mitomycin C alone, or (4) mitomycin C and 20 minutes of pulsed ultrasound. The mean sister chromatid exchange frequencies were 6.7 control cells, 7.5 cells exposed only to ultrasound, 8.1 cells treated with both ultrasound and mitomycin C, and 10.4 cells treated with mitomycin C alone. Neither X2 tests for differences in the four distributions nor analysis of variance for interaction between ultrasound and mitomycin C was significant. Our results suggest that individuals receiving alkylating agents are not likely to be highly susceptible to any deleterious effects of ultrasound. However, these results remain tentative pending repetition of studies and development of more appropriate in vitro exposure systems.

Adult↗
PubMed1984

HLA associations in endometriosis.

A study of 53 individuals failed to reveal an association between any HLA antigen and endometriosis. Division of the sample into those having a relative affected with endometriosis (N = 11) and those not having such a relative (N = 42) similarly failed to reveal significant associations.

Endometriosis↗