Prospective Associations of Homocysteine, Executive Function, and Depressive Symptoms

Associations of cardiovascular risk factors, cognitive performance, and depressive symptoms have been well established. However, the directionality of these associations as well as the specificity of these associations with respect to executive function are less clear. Additionally few studies have determined whether genetic risk factors, such as apolipoprotein-E4 (APOE-E4) genotype, and age moderate the associations of cardiovascular risk factors such as homocysteine with changes in depressive symptoms and how these associations may be mediated by cognitive performance. The primary aim of this study was to analyze the bidirectional associations of a full range of cognitive domains and symptoms of depression over a period of 5 years and to determine the extent to which the conditional associations of homocysteine (moderated by age and APOE-E4 genotype) and changes in depressive symptoms are mediated by cognitive performance. Additionally, we aimed to determine the extent to which these associations are specific to executive function as compared with other domains of cognitive function. After exclusions for probable dementia, kidney dialysis, and acute stroke, 719 adult participants were available for analysis for the sixth and seventh waves of the Maine-Syracuse Longitudinal Study. We conducted cross-sectional multiple linear regression analyses and cross-lagged panel analyses (CLPD) to determine the strength and directionality of associations for cognitive function and symptoms of depression. Next, we conducted conditional mediation path analyses to explore the associations of homocysteine (moderated by age and APOE-E4) and changes in self-reported depressive symptoms as mediated by cognitive function. All models were adjusted for wave 6 demographic covariates (age, sex, education, ethnicity, and marital status), cardiovascular risk profile (Framingham Risk Score), and depressive symptoms. In fully adjusted cross-sectional models, depressive symptoms were inversely associated with executive function and several other cognitive domains. In CLPD, cognitive performance was a stronger and more consistent predictor of changes in depressive symptoms (Executive Function, Global performance, Scanning and Tracking, and Visual-Spatial Organization and Memory) than depressive symptoms were of changes in performance. Although cognitive performance largely did not mediate the associations of cardiovascular risk factors (homocysteine and Framingham Risk Score) and changes in depressive symptoms, we did observe direct associations of Framingham Risk Score and changes in symptoms as well as significant moderation by age and APOE-E4 for the associations of homocysteine and changes in depressive symptoms. For APOE-E4 non-carriers, higher homocysteine was associated with symptom increases for individuals ≥ 74.33 years of age and for APOE-E4 carriers, there were marginal risks for individuals ≤ 45 years of age. The findings of this study have important clinical implications in assessing risk for and prevention of depressive symptoms both via maintenance of cognitive function and CVD risk reduction. Better executive functioning and performance in other cognitive domains was associated with lower levels of depressive symptoms over five years. Lower levels of CVD risk, both for the well-established CVD risk factors indexed by the Framingham Risk Score and for homocysteine, were associated with lower levels of depressive symptoms over five years. Moderation of depressive symptoms may be afforded through interventions designed to maintain executive function and to reduce risk relating to modifiable CVD risk factors such as homocysteine. Clinical trials with patient populations are needed to determine whether modification of homocysteine via dietary or physical activity adjustments could provide effective prevention of depressive symptoms

Evolutionary tracks for Betelgeuse

We have constructed a series of non-rotating quasi-hydrostatic evolutionary models for the M2 Iab supergiant Betelgeuse ($\alpha~Orionis$). Our models are constrained by multiple observed values for the temperature, luminosity, surface composition and mass loss for this star, along with the parallax distance and high resolution imagery that determines its radius. We have then applied our best-fit models to analyze the observed variations in surface luminosity and the size of detected surface bright spots as the result of up-flowing convective material from regions of high temperature in the surface convective zone. We also attempt to explain the intermittently observed periodic variability in a simple radial linear adiabatic pulsation model. Based upon the best fit to all observed data, we suggest a best progenitor mass estimate of $20 ^{+5}_{-3} M_\odot$ and a current age from the start of the zero-age main sequence of $8.0 - 8.5$ Myr based upon the observed ejected mass while on the giant branch.Comment: 27 pages, 11 figures, Revised per referee suggestions, Accepted for publication in the Astrophysical Journa

The history of Salisbury, New Hampshire : from date of settlement to the present time. The whole interspersed with numerous interesting incidents, embellished with maps, cuts, and portraits of distinguished citizens.

Genealogy and biography: p. [439]-863.; Includes index.; Daniel and Ezekiel Webster. An address by Hon. Henry P. Rolfe: p. [865]-878

Mechanistic Basis for High Reactivity of (salen)Co–OTs in the Hydrolytic Kinetic Resolution of Terminal Epoxides

The (salen)Co(III)-catalyzed hydrolytic kinetic resolution (HKR) of terminal epoxides is a bimetallic process with a rate controlled by partitioning between a nucleophilic (salen)Co–OH catalyst and a Lewis acidic (salen)Co–X catalyst. The commonly used (salen)Co–OAc and (salen)Co–Cl precatalysts undergo complete and irreversible counterion addition to epoxide during the course of the epoxide hydrolysis reaction, resulting in quantitative formation of weakly Lewis acidic (salen)Co–OH, and severely diminished reaction rates in the late stages of HKR reactions. In contrast, (salen)Co–OTs maintains high reactivity over the entire course of HKR reactions. We describe here an investigation of catalyst partitioning with different (salen)Co–X precatalysts, and demonstrate that counterion addition to epoxide is reversible in the case of the (salen)Co–OTs. This reversible counterion addition results in stable partitioning between nucleophilic and Lewis acidic catalyst species, allowing highly efficient catalysis throughout the course of the HKR reaction.Chemistry and Chemical Biolog

Challenging the “jolly fat” hypothesis among older adults: High body mass index predicts increases in depressive symptoms over a 5-year period

Several investigators have observed lowered risk of depression among obese older adults, coining the “jolly fat” hypothesis. We examined this hypothesis using baseline and a 5-year follow-up body mass index, depressive symptoms, and covariates from 638 community-based older adults. High objectively measured body mass index and functional limitations predicted increased future depressive symptoms. However, symptoms did not predict future body mass index. Self-reported body mass index showed similar associations despite underestimating obesity prevalence. Results did not differ on the basis of gender. Results for this study, the first longitudinal reciprocal risk analysis between objectively measured body mass index and depressive symptoms among older adults, do not support the “jolly fat” hypothesis

Vascular uptake of rehydration fluids in hypohydrated men at rest and exercise

The purpose of this study was to formulate and to evaluate rehydration drinks, which would restore total body water and plasma volume (PV), for astronauts to consume before and during extravehicular activity, a few hours before reentry, and immediately after landing. In the first experiment (rest, sitting), five healthy men (23-41 yr), previously dehydrated for 24 hr., drank six (1a, 2, 4, 5, 6, 7) fluid formulations (one each at weekly intervals) and then sat for 70 min. Pre-test PV were measured with Evans blue dye and changes in PV were calculated with the hematocrit-hemoglobin transformation equation. This rest experiment simulated hypohydrated astronauts preparing for reentry. The second experiment (exercise, supine) followed the same protocol except four healthy men (30-46 yr) worked for 70 min. in the supine position on a cycle ergometer at a mean load of 71+/-1 percent of their peak aerobic work capacity. This exercise experiment simulated conditions for astronauts with reduced total body water engaging in extravehicular activity

Habitual chocolate intake and type 2 diabetes mellitus in the Maine-Syracuse Longitudinal Study: (1975-2010): Prospective observations

Compounds in cocoa and chocolate have established cardiovascular benefits, including beneficial effects on insulin resistance, a risk factor for type 2 diabetes mellitus. The aims of this study was to investigate relations between habitual chocolate intakes and diabetes mellitus. Cross-sectional and prospective analyses were undertaken on 953 community-dwelling participants (mean age 62 years, 59% women) from the Maine-Syracuse Longitudinal Study (MSLS). Habitual chocolate intakes, measured using a food frequency questionnaire, were related to prevalence of diabetes mellitus (cross-sectionally) and with risk of diabetes measured approximately five years later (prospectively). We also examined the relation between diabetes (the predictor) and chocolate consumption (the outcome) up to 30 years later. Chocolate intake was inversely associated with type 2 diabetes. Compared to participants who consumed chocolate more than once per week, those who never or rarely ate chocolate exhibited a significantly higher odds of having type 2 diabetes 5 years later (OR: 1.91, 95% CI: 1.03, 3.55, p ¼ 0.04), after adjustment for cardiovascular, lifestyle and dietary factors including other polyphenol-rich beverages. However, individuals diagnosed with diabetes prior to the nutritional assessment consumed lower amounts of chocolate at the time of the dietary assessment. Our findings suggest that relations between chocolate and type 2 diabetes may be bi-directional

Influence of Nutrition During the Postweaning-Preflushing Period on Ewe Performance

The objective of this experiment was to study the feasibility of maintaing ewes in drylot on a limited ration during the postweaning - pre-flushing period. The cost of treatment and resulting ewe performance were used to evaluate the feasibility