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Author(s): Meghan Baruth [sup.1] , Rebecca A. Schlaff [sup.1] , Samantha Deere [sup.1] , Jessica L. Walker [sup.2] , Brenna L. Dressler [sup.3] , Sarah F. Wagner [sup.4] , Ashley [...], Introduction Nearly half of all women gain above gestational weight gain (GWG) recommendations. This study assessed the feasibility and efficacy of a pilot behavioral intervention on GWG and physical activity behaviors. Methods Women (n = 45) 14-20 weeks gestation enrolled in a behavioral intervention. Physicians &apos;prescribed&apos; the intervention to low risk patients. The intervention included self-monitoring, support, and optional walking groups. Process evaluation measures regarding usage and acceptability of study components were obtained. Physical activity was objectively measured at baseline and 35 weeks. The percentage of participants with appropriate GWG was calculated. Control data was obtained from the same clinic where participants were recruited. Results Overall, the intervention was acceptable to participants; attrition was low (6.7%), weekly contact was high (87%), and self-monitoring was high (Fitbit worn on 82% of intervention weeks; weekly weighing on 81%). Facebook (40% of weeks) and study website use (19%) was low, as was walking group attendance (7% attended a single group). Participants reported a lack of discussions about the study with their physician. Results showed no significant difference between intervention and control participants in the percentage who gained excess weight (p = 0.37). There was a significant decrease in moderate-to-vigorous physical activity in intervention participants (p < 0.0001). Discussion Continued efforts for promoting physical activity and appropriate GWG are needed. Although acceptable, the intervention was not efficacious. Trainings for, or input from prenatal healthcare providers on how to best encourage and support patients&apos; engagement in healthy behaviors, such as PA, are warranted.

Mutational bias is a potentially important agent of evolution, but it is difficult to disentangle the effects of mutation from those of natural selection. Mutation- accumulation experiments, in which mutations are allowed to accumulate at very small population size, thus minimizing the efficiency of natural selection, are the best way to separate the effects of mutation from those of selection. Body size varies greatly among species of nematode in the family rhabditidae; mutational biases are both a potential cause and a consequence of that variation. We report data on the cumulative effects of mutations that affect body size in three species of rhabditid nematode that vary fivefold in adult size. Results are very consistent with previous studies of mutations underlying fitness in the same strains: two strains of Caenorhabditis briggsae decline in body size about twice as fast as two strains of C. elegans, with a concomitant higher point estimate of the geuomic mutation rate; the confamilial Oscheius myriophila is intermediate. There is an overall mutational bias, such that mutations reduce size on average, but the bias appears consistent between species. The genetic correlation between mutations that affect size and those underlying fitness is large and positive, on average.

It is often assumed that the mutation rate is an evolutionarily optimized property of a taxon. The relevant mutation rate is for mutations that affect fitness, U, but the strength of selection on the mutation rate depends on the average effect of a mutation. Determination of U is complicated by the possibility that mutational effects depend on the particular environmental context in which the organism exists. It has been suggested that the effects of deleterious mutations are typically magnified in stressful environments, but most studies confound genotype with environment, so it is unclear to what extent environmental specificity of mutations is specific to a particular starting genotype. We report a study designed to separate effects of species, genotype, and environment on the degradation of fitness resulting from new mutations. Mutations accumulated for >200 generations at 20[degrees] in two strains of two species of nematodes that differ in thermal sensitivity. Caenorhabditis briggsae and C. elegans have similar demography at 20[degrees], but C. elegans suffers markedly reduced fitness at 25[degrees]. We find little evidence that mutational properties differ depending on environmental conditions and mutational correlations between environments are close to those expected if effects were identical in both environments.

Matrix differences among serum samples from non-pregnant and pregnant patients could bias measurements. Standard Reference Material 1949, Frozen Human Prenatal Serum, was developed to provide a quality assurance material for the measurement of hormones and nutritional elements throughout pregnancy. Serum from non-pregnant women and women in each trimester were bottled into four levels based on pregnancy status and trimester. Liquid chromatography tandem mass spectrometry (LC-MS/MS) methods were developed and applied to the measurement of thyroid hormones, vitamin D metabolites, and vitamin D-binding protein (VDBP). Copper, selenium, and zinc measurements were conducted by inductively coupled plasma dynamic reaction cell MS. Thyroid stimulating hormone (TSH), thyroglobulin (Tg), and thyroglobulin antibody concentrations were analyzed using immunoassays and LC-MS/MS (Tg only). Certified values for thyroxine and triiodothyronine, reference values for vitamin D metabolites, VDBP, selenium, copper, and zinc, and information values for reverse triiodothyronine, TSH, Tg, and Tg antibodies were assigned. Significant differences in serum concentrations were evident for all analytes across the four levels (p≤0.003). TSH measurements were significantly different (p<0.0001) among research-only immunoassays. Tg concentrations were elevated in research-only immunoassays vs. Federal Drug Administration-approved automated immunoassay and LC-MS/MS. Presence of Tg antibodies increased differences between automated immunoassay and LC-MS/MS. The analyte concentrations' changes consistent with the literature and the demonstration of matrix interferences in immunoassay Tg measurements indicate the functionality of this material by providing a relevant matrix-matched reference material for the different stages of pregnancy. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study is to examine the effects of a 12-week, behavioral nutrition intervention on dietary behaviors. Method: Inactive older adults (N = 50) were randomized to a 12-week, behavioral nutrition or physical activity intervention, delivered in a group-based format. Questionnaires assessed fruit and vegetable (FV) consumption, and fat- and fiber-related behaviors at baseline and postintervention. Height and weight were measured. Repeated-measures ANOVAs examined changes in dietary behaviors over time between groups, controlling for age, gender, and education. Results: Participants averaged 64.1 ± 8.4 years of age and had a body mass index (BMI) of 33.3 ± 7.5 kg/m2. Group × Time interactions were significant for FV consumption (p = .003), and fat- (p = .02) and fiber-related (p = .008) behaviors at 12 weeks. At 12 weeks, dietary behaviors improved significantly in the nutrition but not in the physical activity group. Effect sizes were medium to large. Discussion: A 12-week, behavioral nutrition intervention improved dietary behaviors. Behavioral interventions may be a low-cost way to improve dietary behaviors among older adults, potentially affecting population health significantly. [ABSTRACT FROM AUTHOR]

Numerous chemicals, such as pesticides and antimicrobial agents, have been synthesized since the Industrial Revolution. Growing evidence suggests that several classes of organic chemicals can induce or suppress hormonal activity [...]