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Biomedical subjects

J L Simpson

Publications and source records attributed to J L Simpson.

298 records · Page 17Linked to original sources
PubMedDate not supplied

Inability to detect fetal metaphases in flow-sorted lymphocyte cultures based on maternal-fetal HLA differences.

Separation of fetal cells from maternal blood could provide a means for prenatal diagnosis that would not endanger the fetus. In this pursuit, we attempted cytogenetic analysis of candidate fetal cells flow sorted on the basis of parental HLA disparity. Metaphases showing 46,XY or aneuploidy and concordant with prenatal diagnostic studies (i.e., amniocentesis, chorionic villus sampling) would presumably be fetal in origin. Blood samples were obtained from 78 pregnant women and their partners. Among 18 HLA informative cases in which metaphases were recovered, 15 involved fetuses that were 46,XY or aneuploid. From these 15 cases, 2,483 metaphases were analyzed. All metaphases were 46,XX. Cytogenetic analysis of flow-sorted fetal cells thus probably will need to emphasize not metaphase analysis but in situ hybridization with chromosome-specific probes.

Amniocentesis↗
PubMedDate not supplied

Transvaginal chorionic villus sampling using transabdominal ultrasound guidance: a new technique for first-trimester prenatal diagnosis.

Transvaginal chorionic villus sampling (CVS) using concurrent transabdominal ultrasound guidance was performed in 20 women who desired CVS but could not be offered transcervical or transabdominal approaches because of uterine position and placental location. Satisfactory amounts of chorionic villi were obtained in all 20 cases with no maternal discomfort, an occurrence that contrasts with our experience in transvaginal CVS using endovaginal ultrasound guidance. We believe that transvaginal CVS using concurrent transabdominal ultrasound guidance warrants consideration as an alternative technique for first-trimester CVS in selected patients.

Adult↗
PubMedDate not supplied

Severity of abnormality influences decision to terminate pregnancies affected with fetal neural tube defects.

We examined parental decision concerning pregnancy management in women having fetuses with neural tube defects (NTDs) to determine whether severity of defect or method of detection has an impact on the decision making process. Analysis of decisions by 50 women, whose pregnancies were affected by an isolated neural tube defect (NTD) and characterized by a singleton gestation at 24 gestational weeks or less with normal chromosomal complement (46,XX or 46,XY), were assessed. All 23 women carrying fetuses with anencephaly elected to terminate their pregnancies. Of the 27 women carrying fetuses with spina bifida, 21 (77.8%) elected to terminate their pregnancies and 6 (22.2%) elected to continue their pregnancies. Of the 6 pregnancies that were continued, 4 were initially detected by ultrasonography and 2 were ascertained by maternal serum alpha-fetoprotein screening; defects ranged from 2 to 14 vertebral bodies, and none of the defects were craniad to the T9 level. This is in comparison to 5 of the 21 spina bifida cases that were elective pregnancy terminations, which were characterized by fetal lesions craniad to the T9 level. Severity of NTD thus appears to influence the decision to continue or terminate an affected pregnancy.

Abortion, Induced↗
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Hodgkin's disease variant of Richter's syndrome. Report of a case with diagnosis by fine needle biopsy.

BACKGROUND: Chronic lymphocytic leukemia (CLL) with transformation into large cell lymphoma (Richter's syndrome) is a well-documented phenomenon. Only rarely does CLL terminate in Hodgkin's disease (HD) as Richter's syndrome. Reports of Hodgkin's variant of Richter's syndrome proven by histologic and immunohistologic evaluation have been published, but no cytologic reports of this entity exist. Distinguishing between large cell lymphoma and HD as variants of Richter's syndrome is essential because of recent reports of improved prognosis in HD. CASE: We report a case of a 65-year-old male previously diagnosed with CLL who subsequently developed fever, fatigue, an intraabdominal mass and enlarged periaortic lymph nodes. Fine needle biopsy (FNB) and immunophenotyping by flow cytometry of the mass revealed cytologic and immunophenotypical cells of CLL admixed with binucleate and multinucleate cells with prominant eosinophilic nucleoli consistent with Reed-Sternberg cells. CONCLUSION: This is the first reported case of HD variant of Richter's syndrome diagnosed by FNB. As FNB becomes more common in the follow-up of lymphoreticular diseases, cytologists should be aware of this unusual HD variant of Richter's syndrome.

Aged↗
PubMedDate not supplied

Positive serum screening for fetal Down syndrome does not predict adverse pregnancy outcome in absence of fetal aneuploidy.

OBJECTIVE: The purpose of this study was to determine whether false-positive maternal serum screening for fetal Down syndrome is predictive of poor pregnancy outcome. METHODS: The pregnancy outcomes of 99 women having positive serum screening for fetal Down syndrome (study group)--based upon maternal serum alpha-fetoprotein (MSAFP), unconjugated estriol (uE3), hCG, and maternal age--were compared to the outcomes of matched control patients having negative serum screening results (control group). The outcome indices analyzed were fetal death, intrauterine growth retardation (IUGR), preeclampsia, and fetal anomalies. RESULTS: Between the study group and the control group, there were no statistically significant differences in pregnancy outcome with respect to fetal death, IUGR, preeclampsia, or fetal anomalies. CONCLUSIONS: Our findings demonstrate no apparent increase in the adverse perinatal outcomes analyzed in women having unexplained positive serum screening for fetal Down syndrome. Although further investigation is needed, these results provide no evidence to support increased antepartum surveillance in such patients.

Adult↗
PubMedDate not supplied

Molecular analysis to assign parental origin and distinguish de novo i(21q) from t(21q21q) in two Down syndrome fetuses.

OBJECTIVE: We sought to determine the origin of two prenatal cases of chromosome 21 rearrangements not amenable to clarification by conventional cytogenetic methodology. METHODS: Hypervariable repeat polymorphisms (chromosome 21) were used to determine the type of structural rearrangement and the parental origin of the rearranged chromosome. The repeats used were highly polymorphic and located very close to the centromere; thus, the likelihood of differences among the parental alleles and overall informativeness were increased. RESULTS: The rea(21q21q) chromosomes were identified as a Robertsonian translocation in one fetus and an isochromosome in the other. The extra chromosome material was found to be maternal in origin in both cases. CONCLUSION: The ability to clarify the origin of abnormal chromosomal rearrangements provides valuable information concerning possible mechanisms of aneuploidy, as well as clinical data that may have an impact in assessing a patient's risk for abnormal offspring.

Chromosomes, Human, Pair 21↗
PubMedDate not supplied

Cytogenetic analysis of a case of "13q- syndrome" (46,XX,del 13) using banding techniques.

Many chromosomal syndromes include ocular anomalies. In the del(13q) syndrome retinoblastoma, coloboma, and microphthalmia may be present. In the del(13q) case we report, the findings include colobomas and apparent microphthalmia, although the retinoblastoma sometimes associated with this condition was not observed. More precise descriptions of the del(13q) syndrome relative to the region deleted using improved banding techniques may: (1) increase the likelihood of accurate diagnosis, (2) enhance clinical predictions, and (3) possibly further clarify the genetic control over the development of the ocular system.

Abnormalities, Multiple↗
PubMedDate not supplied

[Detection of fetal cells in maternal blood: towards a noninvasive prenatal diagnosis].

Fetal cells exist in maternal blood and can be utilized for prenatal genetic diagnosis. These cells are present during the first and second trimesters, with frequency increasing as gestation advances. Enrichment of erythroblasts by various density gradient techniques and either magnetic activated or flow sorting techniques can be followed by FISH with chromosome-specific DNA probes. This approach has allowed detection of trisomy 21, trisomy 18, Klinefelter syndrome 47,XXY and 47,XYY. Polymerase chain reaction (PCR) analysis of maternal blood has enabled the detection of fetal sex, certain Mendelian disorders (e.g. beta-globin mutations), HLA polymorphisms, and fetal Rhesus (D) blood type. The fetal cell types receiving the most attention has been nucleated erythrocyte (erythroblast) and the trophoblast. Lymphocytes and granulocytes are also present in maternal blood; however, lymphocytes are considered the cell type most likely to persist after pregnancy. A large scale collaborative is now underway in the U.S. that will allow determine whether sensitivity and specificity of this technique provide a noninvasive alternative to conventional methods of prenatal cytogenetic diagnosis.

Cell Separation↗