25 research outputs found
Correlation of Neck Circumference with BMI and Waist Circumference in a High-Risk Urban Cohort
Background
Problem Statement: Obesity is a global epidemic requiring accurate ongoing clinical assessment, as it increases risk of multiple health conditions, such as CVD. Body mass index (BMI) is the most widely used anthropometric measure. Waist circumference (WC) is an accurate measure of visceral fat. Neck circumference (NC) is a newer, simple assessment tool positively correlated with percent body fat, BMI and WC. NC is easier to measure than WC, and unaffected by external factors like lean muscle mass for BMI, and abdominal distension, respiration, and patient discomfort for WC.
Hypothesis: NC, less studied in black patients, who are at higher risk of CVD, is hypothesized to correlate with BMI and WC in a predominantly black, urban patient cohort.
Project Objectives: Investigate the feasibility of integrating NC measurements into routine clinical assessments, emphasizing its simplicity and potential advantages Explore the correlation of NC with BMI and WC in a predominantly black, urban patient cohort with a higher risk of obesity-related conditions
Global Phylogeography with Mixed-Marker Analysis Reveals Male-Mediated Dispersal in the Endangered Scalloped Hammerhead Shark (Sphyrna lewini)
Background: The scalloped hammerhead shark, Sphyrna lewini, is a large endangered predator with a circumglobal distribution, observed in the open ocean but linked ontogenetically to coastal embayments for parturition and juvenile development. A previous survey of maternal (mtDNA) markers demonstrated strong genetic partitioning overall (global W ST = 0.749) and significant population separations across oceans and between discontinuous continental coastlines. Methodology/Principal Findings: We surveyed the same global range with increased sample coverage (N = 403) and 13 microsatellite loci to assess the male contribution to dispersal and population structure. Biparentally inherited microsatellites reveal low or absent genetic structure across ocean basins and global genetic differentiation (FST = 0.035) over an order of magnitude lower than the corresponding measures for maternal mtDNA lineages (W ST = 0.749). Nuclear allelic richness and heterozygosity are high throughout the Indo-Pacific, while genetic structure is low. In contrast, allelic diversity is low while population structure is higher for populations at the ends of the range in the West Atlantic and East Pacific. Conclusions/Significance: These data are consistent with the proposed Indo-Pacific center of origin for S. lewini, and indicate that females are philopatric or adhere to coastal habitats while males facilitate gene flow across oceanic expanses. This study includes the largest sampling effort and the most molecular loci ever used to survey the complete range of
Listeriosis in the Pregnant Guinea Pig: a Model of Vertical Transmission
Feto-placental infections represent a major cause of pregnancy complications, and yet the underlying molecular and cellular mechanisms of vertical transmission are poorly understood. Listeria monocytogenes, a facultative intracellular pathogen, is one of a group of pathogens that are known to cause feto-placental infections in humans and other mammals. The purpose of this study was to evaluate possible mechanisms of vertical transmission of L. monocytogenes. Humans and guinea pigs have a hemochorial placenta, where a single layer of fetally derived trophoblasts separates maternal from fetal circulation. We characterized L. monocytogenes infection of the feto-placental unit in a pregnant guinea pig model and in primary human trophoblasts and trophoblast-derived cell lines. The clinical manifestations of listeriosis in the pregnant guinea pigs and the tropism of L. monocytogenes to the guinea pig placenta resembled those in humans. Trophoblast cell culture systems were permissive for listerial growth and cell-to-cell spread and revealed that L. monocytogenes deficient in internalin A, a virulence factor that mediates invasion of nonphagocytic cells, was 100-fold defective in invasion. However, crossing of the feto-placental barrier in the guinea pig model was independent of internalin A, suggesting a negligible role for internalin-mediated direct invasion of trophoblasts in vivo. Further understanding of vertical transmission of L. monocytogenes will help in designing more effective means of treatment and disease prevention
Reorganization of human cortical maps caused by inherited photoreceptor abnormalities
We describe a compelling demonstration of large-scale developmental reorganization in the human visual pathways. The developmental reorganization was observed in rod monochromats, a rare group of congenitally colorblind individuals who virtually lack cone photoreceptor function. Normal controls had a cortical region, spanning several square centimeters, that responded to signals initiated in the all-cone foveola but was inactive under rod viewing conditions; in rod monochromats this cortical region responded powerfully to rod-initiated signals. The measurements trace a causal pathway that begins with a genetic anomaly that directly influences sensory cells and ultimately results in a substantial central reorganization