Concentrations of antibodies in paired maternal and infant sera: relationship to IgG subclass

Previous studies comparing IgG subclass concentrations in cord and maternal sera have indicated that IgG1 is transported across the placenta to a greater extent than is IgG2. The purpose of our study was to examine the relationship between the transport of IgG1 and IgG2 and the transport of specific antibodies that are relatively restricted to a particular subclass, either IgG1 or IgG2. The concentrations of total serum IgG1 and IgG2 and those of IgG-anti-tetanus toxoid (TT) and anti-group A streptococcal carbohydrate (GAC) were measured in 30 paired maternal and cord sera. Previous studies have shown that anti-TT in adults is predominantly IgG1, whereas anti-GAC is predominantly IgG2. The mean cord/maternal concentration ratios of IgG1 and anti-TT were similar (1.77 +/- 0.56 and 1.93 +/- 0.67, respectively), but differed significantly (P = 0.0001) from those of IgG2 and anti-GAC (0.99 +/- 0.39 and 1.01 +/- 0.45, respectively). We confirmed the difference in cord/maternal concentration ratios of IgG1 and IgG2 antibodies by measuring IgG1 and IgG2 antibodies specific for Haemophilus influenzae type b capsular polysaccharide; the mean cord/maternal concentration ratio of IgG1-anti-Hib PS was significantly higher than that of IgG2-anti-Hib PS (2.23 +/- 0.83 compared with 0.94 +/- 0.49, P = 0.01). These results indicate that placental transport of IgG antibodies is related to their subclass composition.     

Human chorionic gonadotropin testing. Changing testicular response in infants with microphallus and gonadotropin deficiency

The evaluation of microphallus often includes human chorionic gonadotropin (HCG) stimulation to evaluate testicular androgen production. The response in testosterone secretion after five days of stimulation with chorionic gonadotropin is abnormal in patients with either primary testicular defects or gonadotropin deficiency. The testes of gonadotropin-deficient children do respond if the chorionic gonadotropin therapy is continued for six weeks. The current study reports a normal response to the short course (five days) of chorionic gonadotropin therapy in two 2-month-old patients with XY chromosomes with microphallus whose clinical course and repeated testing at age 3 or 4 years indicated gonadotropin deficiency. The normal response in the neonatal period is probably the result of maternal chorionic gonadotropin priming of the fetal testes in utero. These results indicate that HCG testing is an unreliable method for identifying gonadotropin deficiency in the neonatal period.     

Primary and secondary maternal cytomegalovirus infections and their relation to congenital infection. Analysis of maternal sera

4 382 new mothers were examined retrospectively with the enzyme-linked immunosorbent assay (ELISA) for IgG activity to cytomegalovirus (CMV) during pregnancy. Some of them were also studied with the indirect immunofluorescence (IIF) test for CMV-IgM antibodies. All the infants had been studied for CMV excretion within the first week of life. Nineteen of them had been shown to be congenitally infected with CMV. 1 218 (28%) women lacked CMV-IgG activity at their first antenatal visit (usually in months III-IV). Fourteen of them seroconverted before parturition (primary infection). Thirteen of the seroconverters were shown to develop CMV-IgM activity. In 6 (43%) cases the primary infection was transmitted to the offspring. The remaining 13 congenitally infected infants were born to mothers with a positive IgM-test at their first antenatal control. Only one of these mothers had a clearly positive IgM-test. She was shown to lack CMV-antibodies before conception (primary infection during the first trimester). Preconceptional sera were obtained from further 4 of the 13 seropositive mothers of congenitally infected infants; all 4 had CMV antibodies before pregnancy (secondary infection during pregnancy). The combined studies of the mothers and infants revealed that 21-63% of the congenital infections could have been caused by secondary maternal infections. Prospectively performed, the study would only have disclosed one of the three fetal CMV infections that resulted in neurological sequelae.     

Beta-carotene concentrations in maternal and cord blood of smokers and non-smokers

BACKGROUND: Smoking in pregnancy can cause a reduction in the transport of beta-carotene across the placenta, consequently reflecting on the concentrations of this micronutrient in the newborn baby. AIMS: This study determined the concentrations of beta-carotene in maternal blood and umbilical cord blood in a group of smokers and non-smokers. DESIGN AND SUBJECTS: A total of 215 women and respective newborn babies were selected from a hospital in Joinville city, Brazil, between July and November 2002. Women were divided in two groups according to their smoking habits. beta-Carotene concentration was determined by high-performance liquid chromatography (HPLC). The difference between mean concentrations of beta-carotene in maternal blood and cord blood, in smokers and non-smokers, was determined by analysis of variance (ANOVA). The Student's t-test compared mean concentrations of beta-carotene in maternal blood and cord blood, and the mean ingestion of foods rich in beta-carotene by smokers and non-smokers. RESULTS: There was a statistical significant difference between the concentrations of beta-carotene in maternal blood (S=0.271 micromol/L, NS=0.450 micromol/L; P=0.001) and cord blood (S=0.028 micromol/L, NS=0.045 micromol/L; P=0.001) in smokers (S) and non-smokers (NS). The mean concentration of beta-carotene was significantly higher in maternal blood (0.398 micromol/L) than in cord blood (0.041 micromol/L) (P<0.001). The intake of foods rich in beta-carotene was lower in smokers, than in non-smokers (P=0.04). CONCLUSIONS: The concentrations of beta-carotene in maternal blood and cord blood were influenced by the use of tobacco.     

Fructose in fetal cord blood and its relationship with maternal and 48-hour-newborn blood concentrations

Background

Studies have suggested that different non-glucose sugars and sugar alcohols play a role in placental and fetal metabolism. However, the role of fructose in the fetal and newborn metabolism is unclear and studies are scarce.

Aim

Our objective was to investigate the presence of fructose in umbilical cord blood in full-term gestation and its relationship with maternal and 48-hour-old- newborn blood concentrations, to evaluate fructose production by the fetus and newborn infant.

Methods

Blood fructose and glucose concentrations were determined by HPLC in 26 paired samples of maternal blood, umbilical cord vein, and peripheral newborn blood at 48 h after birth. ANOVA, the Friedman Analysis of Variance on Ranks and the Pearson correlation with p < 0.05 were used.

Results

Fructose concentration in umbilical cord blood was higher than maternal blood (p = 0.024), suggesting endogenous fructose production by the fetal-placental unit via the sorbitol pathway. Fructose concentrations were higher in newborns at 48 h after birth than in the fetal umbilical cord blood (p = 0.004), suggesting that fructose production is a continuous process from fetus to newborn.

Conclusions

Fructose production by the sorbitol pathway, present in the fetus and newborn, is an alternative pathway in glucose metabolism probably used to maintain redox balance in the fetus. We suggest that endogenous fructose, similar to dietary ingested fructose, under physiological conditions produces the backbone for triacylglycerol and lipid synthesis in the fetus and newborn. Therefore the route for metabolizing fructose is already present in the early steps of human development.     

IgG-subclass concentrations in cord sera from premature,full term and small-for-dates babies

IgG-subclass concentrations were determined in cord sera from 47 premature, 59 full-term, and 29 small-for-dates babies of varying gestational age. In premature and full term babies the relative percentages of all four subclasses were in the range for normal adult values. However, in small-fordates babies significantly lowered IgG₁-levels were found.

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Zusammenfassung Bei 47 Früh-, 59 Reif- und 29 Mangelgeborenen unterschiedlichen Gestationsalters wurde der IgG-Unterklassengehalt des Nabelschnurserums bestimmt. Bei Früh- und Reifgeborenen lagen die Konzentrationen aller vier Subklassen im Bereich normaler Erwachsenenwerte, bei Mangelgeborenen fanden sich signifikant erniedrigte IgG₁-Spiegel.

     

Free aminoacids and alpha-aminoacid nitrogen in cord and maternal sera at delivery and in nonpregnant women

Summary Serum levels of alpha aminoacid nitrogen and free aminoacids were studied in forty-two newborns, their mothers and in ten non-pregnant healthy women. The alpha aminoacid nitrogen was raised in the cord and maternal sera as compared with the value in the sera of non-pregnant women. The highest levels were seen in the immature babies. Taurine was spotted in more mothers and newborns as compared to non-pregnant women. The levels of many of the aminoacids in sera were highest in the newborns and lowest in the non-pregnant women. The feto-maternal ratio for essential aminoacids was elevated in the fullterm babies and lowest in the immatures while the reverse were the findings for non-essential aminoacids. The role played by the growing placenta with advancing gestation in raising the fetal and to some extent maternal aminoacids and alpha aminoacid nitrogen is discussed. From the Institute of Child Health, and the Department of Ostetrics, Grant Medical College and J.J. Group of Govt. Hospitals, Bombay, 12. Based on the project “Longitudinal Studies on Aminoacids” supported by a University Grants Commission Award to P.M.S. A part of the project was taken for Ph.D. Thesis (Bombay University) by R.S.P.     

Lead concentrations in maternal and cord blood in women users of surma eye cosmetics

A prospective study was undertaken to analyse the lead concentrations in maternal and cord blood of 71 pregnant Arab women at term who used eye cosmetics, particularly "surma". A total of 64 mothers (90%) used eye cosmetics throughout pregnancy, and, of these, 45% used surma. The lead content of the cosmetics available in the market was found to vary between zero and 88%. The mean lead concentrations in all blood samples were higher than the accepted natural levels of 0.001 mumol/l, but lower than the subtoxic level of 1.9 mumol/l. The mean lead concentration of all samples was lower than the subtoxic level of 1.9 mumol/l but higher than that quoted in the literature and suggested to be a natural level (0.001 mumol/l). This indicates that other lead pollutants may be involved. Lead concentrations in maternal and cord blood correlated well, but did not show any significant difference between surma and non-surma users. None of the newborns showed apparent congenital anomalies and their birthweights were comparable to average Saudi birthweights.     

Low bone mineral density in small for gestational age infants: correlation with cord blood zinc concentrations.

Twenty eight term small for gestational age (SGA) infants and 18 term appropriate for gestational age (AGA) infants were studied prospectively to assess bone mineral density and cord serum zinc concentrations. Growth and nutritional status were evaluated, and bone mineral density was measured by dual energy x ray densitometry of the lumbar spine. Cord serum zinc, parathyroid hormone, osteocalcin, vitamin D metabolite and mineral concentrations were measured. Growth, nutritional status, and bone mineral density (mean (SD) 0.223 (0.032) vs 0.277 (0.032) g hydroxyapatite/cm2) were significantly low in SGA infants. Bone mineral density was linearly related to growth and nutritional measures. Cord serum zinc concentrations were in the normal range and similar in both groups (mean (SD) 13.86 (3.0) vs 13.43 (2.1) mumol/l). It is suggested that SGA infants may not be zinc deficient. Low bone mineral density could be caused by growth and nutritional status deficiencies, the mechanisms for which could be those that reduce nutrient substrate supply to the fetus.     

Gonadotropin-releasing hormone (LH-RH) and human chorionic gonadotropin in the treatment of two boys with hypogonadotrophic hypogonadism.

Two brothers, 16 and 14 years of age, with hypogonadotrophic hypogonadism and anosmia were treated with subcutaneous injections of 200 microng gonadotropin-releasing hormone at 8-hour intervals for 4 weeks. Serum FSH increased to the range of normal adult men, but serum LH and serum testosterone showed little change and no clinical signs of pubertal development occurred. Thereafter the 2 patients were given HCG for 11 months and a combination of HCG and HMG for a further 3 months. In response to this treatment, the serum testosterone levels increased to the range of normal adult men and marked development of the secondary sex characteristics was seen.     

Superoxide dismutase activity in the maternal and cord blood.

Superoxide dismutase (SOD) activity was measured in the maternal and cord blood by the modified method of Beauchamp and Fridovich, using a carbonate-buffered (pH 10.2) xanthine-xanthine oxidase system. No great differences between maternal and cord blood in erythrocyte SOD levels were observed, with the exception of whole blood; namely, washed RBC showed a SOD activity of a fairly high level, which was comparable to the activities of crude SOD, but showed no difference between them. In contrast, the SOD activity in the maternal whole blood was significantly lower than that in the cord blood. In measuring SOD activity, the serum factor has a great effect, and serum contains a substance that inhibits NBT reduction. Only one band of SOD has been detected which shows identical Rf values both in maternal and cord blood by polyacrylamide-gel electrophoresis.