Case report: high prenatal bisphenol a exposure and infant neonatal neurobehavior

Context: Most of the U.S. population is exposed to the high-production-volume chemical bisphenol A (BPA), but targetable sources of exposure remain to be determined. Animal studies and one human study suggest that BPA is a neurotoxicant.Case presentation: A mother in the Health Outcomes and Measures of the Environment (HOME) Study, a prospective birth cohort examining prenatal and postnatal environmental toxicants and childhood health outcomes, had a urinary BPA concentration of 583 µg/g creatinine at 27 weeks of pregnancy, which was the highest concentration observed in this cohort (median, 2.0 µg/g creatinine) and the general population. We used prenatal questionnaire data and a follow-up interview to identify potential sources of exposure that included daily plastic use and consumption of canned beverages and foods. Her male infant had a normal newborn neurobehavioral assessment but presented with abnormalities at the 1-month examination that prompted physician referral. Subsequently, the child had normal neurobehavioral testing results at annual evaluations from 1 to 5 years of age.Discussion: Investigations into sources of high gestational urinary BPA concentrations provide an opportunity to identify potential targets for reduction of BPA exposure. This case highlights a potential link between gestational BPA exposure and transient neurobehavioral changes that is hypothesis generating and can serve to alert researchers to potential areas for examination in future studies.Relevance to clinical practice: It is important to educate health care practitioners regarding potential sources of BPA exposure and anticipatory guidance on minimization of exposures during vulnerable periods of development.     

Variability and predictors of urinary bisphenol A concentrations during pregnancy

Background

Prenatal bisphenol A (BPA) exposure may be associated with developmental toxicity, but few studies have examined the variability and predictors of urinary BPA concentrations during pregnancy.

Objective

Our goal was to estimate the variability and predictors of serial urinary BPA concentrations taken during pregnancy.

Methods

We measured BPA concentrations during pregnancy and at birth in three spot urine samples from 389 women. We calculated the intraclass correlation coefficient (ICC) to assess BPA variability and estimated associations between log₁₀-transformed urinary BPA concentrations and demographic, occupational, dietary, and environmental factors, using mixed models.

Results

Geometric mean (GM) creatinine-standardized concentrations (micrograms per gram) were 1.7 (16 weeks), 2.0 (26 weeks), and 2.0 (birth). Creatinine-standardized BPA concentrations exhibited low reproducibility (ICC = 0.11). By occupation, cashiers had the highest BPA concentrations (GM: 2.8 μg/g). Consuming canned vegetables at least once a day was associated with higher BPA concentrations (GM = 2.3 μg/g) compared with those consuming no canned vegetables (GM = 1.6 μg/g). BPA concentrations did not vary by consumption of fresh fruits and vegetables, canned fruit, or store-bought fresh and frozen fish. Urinary high-molecular-weight phthalate and serum tobacco smoke metabolite concentrations were positively associated with BPA concentrations.

Conclusions

These results suggest numerous sources of BPA exposure during pregnancy. Etiological studies may need to measure urinary BPA concentrations more than once during pregnancy and adjust for phthalates and tobacco smoke exposures.     

Breast milk as a source for acquisition of cytomegalovirus (HCMV) in a premature infant with sepsis syndrome: detection by real-time PCR.

Symptomatic disease due to human cytomegalovirus (HCMV) has been increasingly recognized in low birth weight (LBW) premature infants. Breast milk has been identified as a potential source for these infections. At approximately 60 days of life a LBW, premature infant was diagnosed with HCMV sepsis syndrome, prompting further investigation of the source for HCMV acquisition. The infant had received a combination of both fresh and frozen breast milk from his mother throughout his first 2 months of life. We utilized a real-time PCR assay for HCMV DNA to retrospectively examine viral genome copy number in serial samples of stored, frozen breast milk. This analysis indicated an increase in breast milk viral load over the first 45 days of life, heralding the HCMV sepsis syndrome that was observed clinically. Real-time PCR may be a useful tool in the evaluation of HCMV viral load in breast milk.     

Nonporous polyurethane membranes as islet immunoisolation matrices--biocompatibility studies

Novel elastomeric nonporous polyurethane membranes were synthesised with differing hard segment contents for evaluation as possible islet encapsulation matrices. Physico-chemical properties of these membranes were reported earlier by authors and have been found suitable for immunoisolation. In the present study, membranes were evaluated for their in vitro biocompatibility. Membranes T1, T4, T5 and T6 did not show toxicity in direct cell contact study towards L929 fibroblasts. However, T2 and T3 were found cytotoxic and were excluded from further testing. NIH3T3 cells when exposed to leach out products of T4, T5 and T6 showed no cytotoxicity, while T1 decreased cellular viability as confirmed by MTT assay. T4 and T5 alone were seen to be compatible with mouse islets while T6 was incompatible to the mouse islets. Digital image analysis (DIA) studies showed intact morphology of islets cultured on the T4 and T5 with viability (88.4 and 91% respectively) comparable to islets on tissue culture polystyrene (TCPS) control. Islets on T4 and T5 also retained their functionality, as judged by insulin secretion in response to in vitro glucose challenge (16.0 mM). These studies point out the crucial role of surface free energy and hydrophilicity in deciding compatibility of polyurethane membranes with islets of Langerhans. Studies indicate that polyurethane membranes T4 and T5 could be potential candidates for islet immunoisolation.     

“Breastfeeding” without baby: A longitudinal,qualitative investigation of how mothers perceive,feel about,and practice human milk expression

Most American mothers who produce human milk (HM) now pump in place of some or all feeding at the breast, and most American infants are now fed pumped HM. We aimed to investigate mothers' perceptions of, attitudes toward, and practices for pumping and providing pumped HM. Results related to pumping are reported here. We conducted in‐depth, semi‐structured interviews among a diverse sample of 20 mothers who pumped, following each from pregnancy through infant HM‐feeding cessation up to 1 year postpartum. Data were analyzed using thematic analysis with Atlas.ti. Mothers' reasons for pumping changed over time and reflected their needs and desires (e.g., latch difficulty, return to work, and increasing their milk supply). Mothers reported that pump type and quality were important to pumping success and that pumping was time‐consuming, costly, and unpleasant compared to feeding at the breast. Regardless of how often mothers pumped, most felt pumping was necessary to meet their infant HM‐feeding goals and was a welcome means of sharing with other caregivers the bonding opportunity and tasks they associated with feeding infants. Mothers interpreted output from pumping sessions to understand their ability to provide enough milk to meet their infants' needs. Mothers' reasons for pumping may signal constraints to infant HM feeding that may be addressed with policy changes. Mothers' attitudes and perceptions toward pumping indicate that, although pumping fills important and welcome roles for many mothers, the reality of its practice may make it an unacceptable or infeasible substitute for some.     

Differences in both inositol 1,4,5-trisphosphate mass and inositol 1,4,5-trisphosphate receptors between normal and dystrophic skeletal muscle cell lines

Human normal (RCMH) and Duchenne muscular dystrophy (RCDMD) cell lines, as well as newly developed normal and dystrophic murine cell lines, were used for the study of both changes in inositol 1,4,5-trisphosphate (IP₃) mass and IP₃ binding to receptors. Basal levels of IP₃ were increased two- to threefold in dystrophic human and murine cell lines compared to normal cell lines. Potassium depolarization induced a time-dependent IP₃ rise in normal human cells and cells of the myogenic mouse cell line (129CB3), which returned to their basal levels after 60 s. However, in the human dystrophic cell line (RCDMD), IP₃ levels remained high up to 200 s after potassium depolarization. Expression of IP₃ receptors was studied measuring specific binding of ³H-IP₃ in the murine cell lines (normal 129CB3 and dystrophic mdx XLT 4-2). All the cell lines bind ³H-IP₃ with relatively high affinity (K_d: between 40 and 100 nmol/L). IP₃ receptors are concentrated in the nuclear fraction, and their density is significantly higher in dystrophic cells compared to normal. These findings together with high basal levels of IP₃ mass suggest a possible role for this system in the deficiency of intracellular calcium regulation in Duchenne muscular dystrophy. © 1998 John Wiley & Sons, Inc. Muscle Nerve 21:902–909, 1998.