Laurence E. Karp

Cultivated cells from diagnostic amniocentesis in second trimester pregnancies. I. Clonal morphology and growth potential.

Extract: Amniotic fluid obtained transabdominally for prenatal diagnosis (mean length of amenorrhea 16.1 weeks) contained between 10 and 10 cells/ml, the great majority of which were squamous; their labeling index with ( H)thymidine was < 2 × 10-3. An average of 3.5 clones ( > 10 cells)/ml fluid grew; of these, an average of 1.5 grew for >20 population doublings (CPD). Of 288 clones analyzed from 20 cases, 271 could be classified into one of three groups: group I, 24 were typical fibroblast-like cells (F cells) comparable with control clones from neonatal dermis with macroscopic “ribbing” growth pattern of megaclones, preponderance of spindle-shaped cells growing in parallel arrays, and high growth potential (mean of selected clones = 53 CPD); group II, 67 were typical epithelioid types (E cells) consisting of cells with intimate cell-to-cell contact which were resistant to trypsin detachment, with poor subcloning efficiencies and poor growth potential (mean of selected clones 14.5 CPD); group III, the predominant class with 180 clones, was of a type not described previously (AF cells); their megaclones had “bulls-eye” growth patterns, individual cells were pleomorphic, and growth potentials were intermediate to those of E and F cells. This tripartite classification holds for the majority of samples, but individual variation is suggested by the observation of exceptional clonal types sharing characteristics of both the E and AF class.Speculation: The AF cell is the predominant type in most diagnostic amniotic fluid cultures; heretofore, such cultures were widely regarded as consisting primarily of fibroblast and epithelial-like cells. Skin fibroblast cultures are therefore inappropriate controls for the interpretation of constitutive and induced levels of enzymes in such cultures. Established amniotic fluid cell cultures are derived from a single or a few clonable cells with high growth potential and therefore may not always be representative of the fetus.

Selection of human spermatozoa according to their relative motility and their interaction with zona-free hamster eggs

Human spermatozoa were separated according to their motility by centrifuging semen on discontinuous Percoll gradients. Fractions of the gradients were examined for sperm motility, velocity, viability, morphology, bacteria, and sperm function using the hamster ova sperm penetration assay. The percentage of motile sperm increased from 40% to 60% motile sperm in 60% Percoll to 90% to 100% Percoll. Sperm velocity increased proportionately. Staining showed that greater than 90% of sperm in the 100% Percoll were alive and had normal morphology, and that only sperm cells were found in Percoll concentrations greater than 80%. Sperm isolated in the 80% to 100% Percoll fractions penetrated hamster ova much more frequently than sperm found in the 60% to 70% fractions or than sperm that had not been separated on a Percoll gradient.

Possible relationship between in utero diethylstilbestrol exposure and male fertility

Seventeen men who were exposed in utero to diethylstilbestrol (DES), 12 non-DES-exposed volunteers, and 11 fertile control subjects were evaluated by physical examination, seminal fluid analysis, and sperm penetration assay (SPA). Fourteen of the 17 male subjects exposed to DES in utero and two of the 12 non-DES-exposed volunteers had SPAs of less than 14% and qualified as infertile by the criteria of this test. All 11 fertile control subjects had demonstrated SPA values in the fertile range. Thirteen of the 17 DES-exposed male subjects, four of the 12 non-DES-exposed volunteers, and four of the 11 fertile control subjects demonstrated at least one abnormality of the reproductive organs.

Evaluation of elective repeat cesarean section as a standard of care: An application of decision analysis

The rationale for routine repeat cesarean section (RCS) is avoidance of uterine rupture during labor. However, the incidence of uterine rupture following modern cesarean section is low, and the charge for cesarean section is greater than that for a trial of labor (TOL). The technique of decision analysis was used to investigate strategies of elective RCS and TOL with precautionary monitoring. Hypothetical cohorts of 10,000 pregnant women with previous low-transverse cesarean incisions were assumed. Probability data were obtained from the literature. In the TOL cohort, 6,623 patients were delivered vaginally. Uterine rupture occurred in 73 patients. In spite of this, TOL resulted in 37 fewer perinatal deaths and 0.7 fewer maternal deaths than elective RCS. The excessive perinatal mortality in the RCS cohort was related to iatrogenic prematurity that is now avoidable with the lecithin/sphingomyelin test. Direct costs were

Benefits of the sperm (hamster ova) penetration assay in the evaluation of the infertile couple

5 million greater in the RCS cohort. We concluded that in contemporary practice mortality rates are essentially equal for both delivery practices. However, substantial cost savings are available with TOL.

Prenatal prediction in myotonic dystrophy: Guidelines for genetic counseling

The males of 310 infertile couples and 30 control couples (current pregnancy) were evaluated with the sperm (hamster ova) penetration assay (SPA) and seminal fluid analysis (SFA). The SPA was found to have a sensitivity of 100% and a specificity of 97% compared to 41% and 90%, respectively, for the SFA. The highest degree of concordance of the two tests existed when both tests were abnormal and no female factor was identified. The poorest concordance occurred when the SFA was normal and no female infertility factor was identified. In almost all cases of unexplained infertility where no female infertility factor was present, the problem could be assigned to the man, as evidenced by an abnormal SPA. The SFA seemed to have some predictive value with respect to the outcome following treatment of the man.

Small structural changes of chromosome 8

Prenatal prediction of myotonic dystrophy (Dm) is feasible because Dm is closely linked to the secretor (Se) locus and the Se status of the. fetus can be determined by examination of the amniotic fluid. A pregiiant woman with Dm and her husband presented a favorable mating for prenatal diagnosis. A Se‐negative fetus would have been at high risk for Dm (92%, allowing for recombination). The fetus was found to he Se‐positive and pregnancy was not terminated. Overall, 37.5% of matings are potentially favorable for prenatal prediction by linkage. The affected parent must be heterozygous at the secretor locus; the spouse must he either se/se or potentially Se/se. Otherwise, prenatal diagnosis is impossible. Guidelines have been prepared for intrauterine prediction of myotonic dystrophy in matings of various Se genotypes.

Experimental Production of Aneuploidy in Mouse Oocytes

SummaryTwo patients are described whose clinical features are interpreted as resulting from simple deletion of, respectively, bands p12 and q242 of chromosome 8.

Somatic stability of variant C-band heterochromatin.

The normal course of meiosis can be interrupted in cultured mouse oocytes by exposre to low temperature (23 degrees C). Re-transfer of the oocytes to a 37 degrees C environment will permit the meiotic process to resume and progress as usual to second metaphase. However, a significant number of oocytes treated in this manner prove to contain abnormal numbers of chromosomes.

Use of ultrasound in the prenatal exclusion of primary microcephaly

SummaryProminent C-band markers were found to be unchanged between different tissues of 9 individuals and during long term culture of 8 skin fibroblast and amniotic fluid cell strains.