Obesity affects short-term folate pharmacokinetics in women of childbearing age.

Maternal folate status and body mass index (BMI) are independent risk factors for neural tube defects (NTD). Population-based studies have identified an inverse association between serum folate and BMI, after adjusting for intake. The objective of this intervention study was to compare the relationship between BMI and the short-term pharmacokinetic response to an oral dose of folic acid. Healthy obese (BMI 30.0 kg m(-2); n=16) and normal-weight (BMI 18.5-24.9 kg m(-2); n=16) women of childbearing age (18-35 years) were administered a single oral dose of folic acid (400 µg). Blood samples were collected over a 10-h period to evaluate the serum folate response. Fasting baseline serum folate was lower in the obese group (P=0.005); in contrast, red blood cell folate was higher (P=0.05). Area-under-the-curve for the absorption phase (0-3 h) and peak serum folate concentrations were lower in obese versus normal-weight women (P<0.005). Overall serum folate response (0-10 h) was lower in obese versus normal-weight women (repeated-measures ANOVA, P=0.001). Data suggest body distribution of folate is significantly affected by obesity, and, should pregnancy occur, may reduce the amount of folate available to the developing embryo. These findings provide additional support for a BMI-adjusted folic acid intake recommendation for NTD risk reduction.

Quantitative comparisons of 16S rRNA gene sequence libraries from environmental samples.

To determine the significance of differences between clonal libraries of environmental rRNA gene sequences, differences between homologous coverage curves, CX(D), and heterologous coverage curves, CXY(D), were calculated by a Cramér-von Mises-type statistic and compared by a Monte Carlo test procedure. This method successfully distinguished rRNA gene sequence libraries from soil and bioreactors and correctly failed to find differences between libraries of the same composition.

Association between results of ambulatory electrocardiography and development of cardiomyopathy during long-term follow-up of Doberman pinschers.

OBJECTIVE: To characterize ambulatory electrocardiographic results of overtly healthy Doberman Pinschers and determine associations between those results and development of dilated cardiomyopathy. DESIGN: Cohort study. ANIMALS: 114 (58 male, 56 female) overtly healthy Doberman Pinschers without echocardiographic evidence of cardiac disease on initial examination. PROCEDURE: Echocardiograms and 24-hour ambulatory electrocardiograms (Holter recordings) were obtained initially and at variable intervals. The status (live vs dead) of all dogs was known at least 2 years and as long as 10 years after initial examination (mean [+/- SD] follow-up time, 4.33 +/- 1.84 years). Associations between development of dilated cardiomyopathy and number of ventricular premature contractions (VPC), age, and sex were determined. RESULTS: 55 dogs (48%) did not have VPC on initial Holter recordings, and only 8 dogs had > 50 VPC/24 hours. The likelihood that a dog would have VPC was associated with increasing age and being male. At least 1 VPC/24 hours, and in particular, > 50 VPC/24 hours or > or = 1 couplet or triplet of VPC/24 hours, were predictive of subsequent development of dilated cardiomyopathy. Fifty-four dogs (47%) developed dilated cardiomyopathy; 12 were still alive at the end of the study, and 42 had died. Twenty-five of these 42 dogs died after the onset of congestive heart failure (CHF), 15 died suddenly before the onset of overt CHF, and 2 died of noncardiac causes. More males developed dilated cardiomyopathy than females, and dogs that died suddenly were approximately 1 year younger than those that developed CHF. CONCLUSIONS AND CLINICAL RELEVANCE: Results of high-quality Holter recordings may be used to identify overtly healthy Doberman Pinschers that are at a high risk for dilated cardiomyopathy.