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Biomedical subjects

J L Chervenak

Publications and source records attributed to J L Chervenak.

7 recordsLinked to original sources
PubMed2000

Episialin acts as an antiadhesive factor in an in vitro model of human endometrial-blastocyst attachment.

Episialin, which is found on the apical membrane of human endometrial epithelium, has been postulated to act as an antiadhesive factor through the steric hindrance generated by its extensively glycosylated structure. The present studies were designed to test this hypothesis in an in vitro model of endometrial-blastocyst attachment. Episialin was expressed in human endometrial carcinoma cells (HEC-1A > RL95-2), and attachment of JAr choriocarcinoma cells to the endometrial cell monolayers was inversely related to episialin expression. Treatment of endometrial monolayers with type III sialidase increased JAr binding, and this increase was suppressed by HMFG1, a monoclonal antibody specific for episialin. The effects of sialidase appear to have resulted from a contaminant protease rather than from a loss of sialic acid residues, because sialidase preparations other than type III were ineffective. After sialidase treatment, conditioned medium from cells treated with type III sialidase contained more episialin than medium from cells treated with other sialidase preparations. Similar attachment-assay results were obtained using O-sialoglycoprotein endopeptidase; after treatment, the increase in JAr binding (>50%) was suppressed by the antiepisialin antibody. These results demonstrate for the first time that episialin acts as an antiadhesive agent in a model of human endometrial-blastocyst attachment.

Blastocyst↗
PubMed1989

Macrosomia in the postdate pregnancy: is routine ultrasonographic screening indicated?

Macrosomia is a potential but often overlooked consequence of the postdate pregnancy. A total of 317 consecutive patients with well-dated pregnancies who were seen because of fetal surveillance at greater than 41 weeks' gestation had an estimation of the fetal weight based on femur length and abdominal circumference at the initial visit. The incidence of macrosomia at 41 weeks' gestation was 25.5%. There was a higher incidence of cesarean section because of arrest and protraction disorders in the postdate pregnancies in which the infant was macrosomic (22%) versus those in which the infant was not macrosomic (10%, p less than 0.01). In a control group of 100 consecutive women delivered between 38 and 40 weeks' gestation, the incidence of macrosomia was 4%, significantly lower than the rate in the postdate patients (p less than 0.01). Incidence of cesarean section because of arrest and protraction disorders was significantly lower in this group (6%, p less than 0.05). The sensitivity and specificity of an estimated fetal weight greater than 4000 gm to predict a birth weight greater than 4000 gm were 60.5% and 90.7%, respectively, with a positive predictive value of 70% and a negative predictive value of 87%. We conclude that routine ultrasonographic screening for macrosomia may be a valuable adjunct to current fetal surveillance protocols used in the postdate pregnancy.

Cesarean Section↗
PubMed1989

Prenatal informed consent for sonogram: an indication for obstetric ultrasonography.

Currently in the United States there is widespread agreement that obstetric ultrasonography should be performed when indicated, based on a beneficence-based calculus. However, there is considerable uncertainty that routine ultrasonography is similarly indicated for every pregnant woman. We argue that the standard of care demands that prenatal informed consent for sonogram be accepted as an indication for the prudent use of obstetric ultrasonography performed by qualified personnel. Prenatal informed consent for sonogram, a primarily autonomy-based indication, should be given the same weight in clinical judgment and practice as the beneficence-based indications listed by the National Institutes of Health consensus panel.

Beneficence↗
PubMed1989

Exact timing of the one-hour glucose sample as a factor in the screen for gestational diabetes.

We examined the exactness of the timing of the 1-hour glucose sample following a 50-g oral glucose challenge as a critical variable in interpretation of the test. Heparin locks were placed in 45 pregnant patients between 25 and 28 weeks' gestation, and 5 patients between 30 and 33 weeks' gestation. Venous samples were taken at intervals of 50, 60, and 70 minutes from completion of the ingestion of a 50-g oral glucose load. We found all of the nine possible patterns of blood glucose values that can derive from three sequential values. There was no consistent relationship between these 60 +/- 10 minute values. Two of the patients had a 60-minute value greater than 140 mg/dL, but a 50- or 70-minute value that was less than 140 mg/dL. Four of the patients had a 50- or 70-minute value that was greater than 140 mg/dL, but a 60-minute value that was less than 140 mg/mL. The range of results in this study reflects a continuum of values that change rapidly over time and in patterns that are not predictable. We conclude that accurate timing is important to avoid erroneous interpretation of the 1-hour glucose screen.

Adolescent↗