Trabecular microstructure is influenced by race and sex in Black and White young adults.

Lower fracture rates in Black men and women compared to their White counterparts are incompletely understood. High-resolution imaging specific to trabecular bone may provide insight. Black participants have enhanced trabecular morphology. These differences may contribute to the lower fracture risk in Black versus White individuals. INTRODUCTION: Lower fracture rates in Black men and women compared to their White counterparts may be explained by favorable bone microstructure in Black individuals. Individual trabecular segmentation (ITS) analysis, which characterizes the alignment and plate- and rod-like nature of trabecular bone using high-resolution peripheral quantitative computed tomography (HR-pQCT), may provide insight into trabecular differences by race/ethnic origin. PURPOSE: We determined differences in trabecular bone microarchitecture, connectivity, and alignment according to race/ethnic origin and sex in young adults. METHODS: We analyzed HR-pQCT scans of 184 adult (24.2 ± 3.4 years) women (n = 51 Black, n = 50 White) and men (n = 34 Black, n = 49 White). We used ANCOVA to compare bone outcomes, and adjusted for age, height, and weight. RESULTS: Overall, the effect of race on bone outcomes did not differ by sex, and the effect of sex on bone outcomes did not differ by race. After adjusting for covariates, Black participants and men of both races had greater trabecular plate volume fraction, plate thickness, plate number density, plate surface area, and greater axial alignment of trabeculae, leading to higher trabecular bone stiffness compared to White participants and women, respectively (p < 0.05 for all). CONCLUSION: These findings demonstrate that more favorable bone microarchitecture in Black individuals compared to White individuals and in men compared to women is not unique to the cortical bone compartment. Enhanced plate-like morphology and greater trabecular axial alignment, established in young adulthood, may contribute to the improved bone strength and lower fracture risk in Black versus White individuals and in men compared to women.

Assessment of the Effectiveness of Combat Eyewear Protection Against Blast Overpressure.

It is unclear whether combat eyewear used by U. S. Service members is protective against blast overpressures (BOPs) caused by explosive devices. Here, we investigated the mechanisms by which BOP bypasses eyewear and increases eye surface pressure. We performed experiments and developed three-dimensional (3D) finite element (FE) models of a head form (HF) equipped with an advanced combat helmet (ACH) and with no eyewear, spectacles, or goggles in a shock tube at three BOPs and five head orientations relative to the blast wave. Overall, we observed good agreement between experimental and computational results, with average discrepancies in impulse and peak-pressure values of less than 15% over 90 comparisons. In the absence of eyewear and depending on the head orientation, we identified three mechanisms that contributed to pressure loading on the eyes. Eyewear was most effective at 0 deg orientation, with pressure attenuation ranging from 50 (spectacles) to 80% (goggles) of the peak pressures observed in the no-eyewear configuration. Spectacles and goggles were considerably less effective when we rotated the HF in the counter-clockwise direction around the superior-inferior axis of the head. Surprisingly, at certain orientations, spectacles yielded higher maximum pressures (80%) and goggles yielded larger impulses (150%) than those observed without eyewear. The findings from this study will aid in the design of eyewear that provides better protection against BOP.

Cost and efficacy of immunosuppression using generic products following living donor liver transplantation in India.

BACKGROUND: Cost of post liver transplant immunosuppression is a major financial burden to patients in developing countries. In India, generic varieties of various immunosuppressants are often used without any definite evidence to their efficacy. This study was aimed at studying the dosage, side effect profile and cost of post-liver transplant immunosuppression using generic products in Indian population following living donor liver transplantation (LDLT). METHODS: Data on dose, cost, and toxicity of immunosuppression were retrieved retrospectively from case records of 59 patients who had undergone LDLT at our center. RESULTS: Adequate immunosuppression was obtained by tacrolimus (Pangraf(®)-Panacea) of 0.04 to 0.05 mg/Kg, and mycophenolate (Mycept(®)-Panacea) of 500 to 1,000 mg; the acute rejection rate was 15% during the first month. Serum tacrolimus levels were 5.4 to 7.3 ng/mL. The cost of immunosuppression varied from Rs. 28,705 in the first month to Rs. 8,820 per month at the end of first year, amounting to an average monthly cost of Rs. 17,250. Approximately 23% and 51% of cost was for mycophenolate and for drug level measurement of tacrolimus, respectively. CONCLUSION: Average cost of immunosuppression after LDLT in India is much lower than that reported elsewhere in the world, since lower drug doses are needed and cheaper generic drugs are available. This can be reduced further by decreasing the frequency of tacrolimus drug level measurement.