Comparisons of human placental lactogen mRNA levels from placentas of diabetics and normal term.

Overt diabetes and gestational diabetes (1-2.5% of all pregnancies) has been related to perinatal mortality, increased macrosomia and increased frequency of other pregnancy complications. Human placental lactogen (hPL), a hormone similar to growth hormone, is produced by the placenta and is a potent antagonist to insulin action. While hPL's presence in maternal circulation induces a sparing effect on nutrients including glucose, it exacerbates diabetes during pregnancy and may well relate to other clinical complications. To explore possible regulation of hPL in diabetic pregnancy and specifically to examine gestational diabetes, we have evaluated the levels of placental mRNA coding for hPL synthesis as well as other parameters from diabetic and normal term patients. By in vitro translation assays using nuclease-treated reticulocyte lysate, no substantial differences in translatable hPL-mRNA were observed when comparing normal term (3.5% of total synthesis), gestational diabetic (3.4%) and Type C diabetic (3.5%). However, translatable hPL-mRNA in Type R diabetes which was 2.7% of total synthesis was slightly reduced in comparison to normal term. To determine more directly hPL-mRNA levels in gestational diabetic placentas and normal term placentas, total RNA preparations were evaluated qualitatively by northern blot and quantitatively by dot blot of RNA and cDNA hybridization to a nick-translated hPL-pMB9 plasmid. The northern blot revealed no major size differences of the mRNA and the dot blot hybridization was quantitatively similar for both gestational diabetics and normal terms per unit of total RNA. By direct analysis of DNA per g tissue we found the DNA content of placentas from gestational diabetics and normal term to be statistically the same.(ABSTRACT TRUNCATED AT 250 WORDS)

Increased rates of polypeptide chain elongation in placental explants from human diabetics.

Average rates of polypeptide chain elongation were determined in placental explants of first trimester and term placentas from both normal and diabetic human pregnancies. Average ribosome half-transit times were determined by measuring the kinetics of transfer of labeled polypeptides from polysomal-bound to released polypeptides. The average half-transit time decreases from 75 sec per ribosome in first trimester explants to 56 sec per ribosome in term placentas. The average polypeptide molecular weights synthesized by explants from first trimester and in term are 49,300 and 49,600, respectively, which are not significantly different. The average elongation rates for first trimester and term placental explants are 172 and 231 amino acids per minute per ribosome, respectively, which are significantly different. Moreover, the average polypeptide molecular weight synthesized by term placentas from diabetic pregnancies is 48,200, while the average ribosome half-transit time is 40 sec. Thus, ribosomes from explants of term placenta from diabetics move along the average message at a much higher speed than do ribosomes in normal term tissue. The assembly rate of amino acid into polypeptide in explant of placenta of diabetic mothers is 314 amino acids per minute, which is significantly faster than 231 amino acids per minute in normal term tissue. These findings indicate that during placental development and in diabetic pregnancy there is a large change in the actual rates at which amino acids are added to the nascent polypeptide chain--i.e., the rates in polypeptide chain elongation. Therefore, translation-level regulation of protein synthesis in placenta plays a significant part in the magnitude of the response to developmental and other physiological stimulations.

Use of intravenous immune globulin in pregnant women with common variable hypogammaglobulinemia.

Two patients with common variable hypogammaglobulinemia were treated with immune serum globulin during pregnancy. An intravenous immune serum globulin preparation was used in the last trimester of pregnancy. Both patients tolerated this preparation well and had an uneventful pregnancy. The two term newborns were healthy and had cord blood IgG levels likely to be the result of transplacental transfer of the intravenous immune serum globulin preparation. During pregnancy there is an increase in the IgG distribution space due to plasma volume expansion. Therefore, pregnancy is an indication for these immune serum globulin preparations that can be administered at high doses intravenously in order to confer adequate protection to the mother and the newborn.

Effect of transfer RNA from various sources on placental messenger RNA translation.

Poly(A+)-containing mRNA from human term placenta was used to direct protein synthesis in a nuclease-treated rabbit reticulocyte lysate, which is dependent on mRNA and tRNA for maximal activity. The major protein product was human pre-placental lactogen (hPL). Addition of tRNA from rabbit liver, rabbit reticulocyte, human first trimester and term placenta, human liver and yeast resulted in 2-5-fold stimulation of [35S]methionine incorporation into total protein. Although all mammalian tRNA increased hPL synthesis, the relative synthesis as compared to endogenous globin was markedly different and most efficient with tRNA from term placenta. Addition of yeast tRNA increased total incorporation 3-fold but decreased incorporation of [35S]methionine into pre-hPL. These results suggest that the population of isoacceptor tRNAs may influence the expression of hPL in term placenta. Results are discussed by showing codon bias and usage of mRNA coding for hPL, alpha- and beta-hCG, rabbit globin and yeast alcohol dehydrogenase I.

Chlamydia trachomatis infection in mothers and infants. A prospective study.

The incidence of chlamydia trachomatis infection of the cervix during pregnancy was found to be 18% in a group of 1,327 women attending the prenatal clinic of a large urban hospital. There were no statistically significant differences between infected and uninfected women in the type or frequency of complications of pregnancy. Chlamydial infection was demonstrated in 27 (28%) of 95 infants born vaginally to infected mothers. Conjunctival infection in these infants was detected earlier than nasopharyngeal infection and the conjunctivae appeared to be the usual portal of entry for the organism. Infants were observed through the age of 12 weeks. Conjunctivae, but the chlamydial pneumonia syndrome occurred in only three (17%) of 18 infants with nasopharyngeal infection.

A modern approach to management of pregnant diabetics: a two-year analysis of perinatal outcomes.

Increased understanding of maternal-fetal carbohydrate homeostasis together with modern perinatal technology now provides a more rational basis for obstetric management of the pregnant diabetic patient. These concepts were applied at MacDonald House in the care of 96 diabetic pregnant women over a two-year period. Pregnancy outcomes were compared with prior experiences with the same group of women. The perinatal mortality rate was reduced from 13.5 to 4.2%, and the rate of macrosomia (infants large for gestational age) was reduced from 30.9 to 17.7%. Patients with gestational diabetes, with a prior loss rate of 8.3%, suffered no losses in the current series. Maternal age was not found to correlate with an untoward outcome in this subgroup.