134 research outputs found
Cholesterol and Alzheimer's Disease Risk: A Meta-Meta-Analysis
Background: Alzheimer''s disease (AD) is the most common subtype of dementia. In the last ten years, the relationship between cholesterol and AD has been investigated. Evidence suggests that cholesterol is associated with AD and represents promising targets for intervention. However, the causality of these associations is unclear. Therefore, we sought to conduct a meta-meta-analysis to determine the effect of cholesterol on the development AD. Then, we assessed the effect of serum levels of low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC) and triglycerides (TG), on AD risk. Methods: A systematic search of meta-analyses was conducted. Scopus, Web of Science, Science direct, PubMed and Google academic system databases were reviewed. Results: We found 100 primary studies and five meta-analyses to analyze the relationships between cholesterol and AD. The total effect of cholesterol on risk of AD was significant and heterogeneous. Subgroup analysis shows that LDL-C levels influence the development of AD. However, non-significant effects of HDL-C, TC and TG levels on AD were found. Conclusions: These results strengthen the evidence that LDL-C cholesterol levels increase risk for AD. More initiatives to investigate the relationship between cholesterol and AD are needed
¿La depresión aumenta el riesgo de demencia? Meta-análisis actualizado de estudios prospectivos
Objetivo. Realizar un meta-análisis actualizado de estudios prospectivos que evalúen la asociación entre la depresión y el riesgo de demencia.
Metodología. Se realizó una búsqueda bibliográfica en Pubmed para identificar estudios publicados desde enero de 2014 hasta marzo del 2019. Se seleccionaron estudios prospectivos con seguimiento mínimo de 1 año; evaluación de la depresión y ausencia de demencia y deterioro cognitivo leve (DCL) al inicio del estudio. Calculamos el riesgo relativo combinado (RR) mediante un modelo de efectos aleatorios, y la fracción de demencia poblacional atribuible (FAP) a la depresión.
Resultados. Ocho cohortes fueron incluidas. Obtuvimos una asociación estadísticamente significativa entre la depresión y el riesgo de demencia, con un RR global de 1, 63 (IC 95%: 1, 30-2, 04), y una FAP de 9, 0% (IC 95%: 4, 5%-14, 1%).
Conclusiones. La depresión se asocia con un aumento de riesgo de demencia en este meta-análisis.
Background. Our primary aim was to conduct an update meta-analysis of prospective studies investigating the association between depression and dementia risk.
Methods. We searched Pubmed database to identify all relevant papers published from January 2014 to March 2019. Prospective studies with a minimum follow-up period of 1 year, baseline depression assessment, absence of dementia or mild cognitive impairment at baseline were selected. We calculated pooled relative risks (RR), with a random effect model, as well as compute population attributable fraction (PAF) of dementia due to depression.
Results. Eight cohorts were included. A statistically significant association between depression and dementia risk, with a pooled RR of 1.63 (95% CI: 1.30-2.04), and a PAF of 9.0% (95% CI: 4.5%-14.1%), were found.
Conclusions. Depression is associated with an increased risk of dementia in this meta-analysis
Effects of resistance training on depression and cardiovascular disease risk in black men: Protocol for a randomized controlled trial
Background
Depression is severely undertreated in Black men. This is primarily because Black men are less likely to seek traditional psychiatric treatment, have less access and more barriers to treatment, and perceive more stigma associated with treatment. Depression contributes to cardiovascular disease (CVD), and Black men have the highest rate of mortality from CVD. Resistance training (RT) can have beneficial effects on both depression and CVD. This study will be the first randomized controlled trial to test the effects of RT on depression and cardiovascular health in a sample of depressed Black men.
Method
Fifty Black men with clinically significant symptoms of depression will be randomized to either (a) a 12-week RT or (b) an attention control group. Behavioral Activation techniques will be used to support adherence to home-based RT goals. Both groups will meet on-site twice/week during the 12-week program, and follow-up assessments will occur at the end-of-treatment and 3 months post-treatment. Qualitative interviews will be conducted after the 3-month follow-up. The objectives of this study are (1) to assess the feasibility and acceptability of recruitment, retention, and intervention procedures, (2) to obtain preliminary evidence of efficacy, and (3) to explore potential mediators of the effects of RT on depression.
Discussion
This study will advance the field of minority men\u27s health by producing new data on the effects of RT for depression, the potential mechanisms of action that may support its use, and its effects on markers of CVD risk in Black men
Functional Analyses of the Plant Photosystem I–Light-Harvesting Complex II Supercomplex Reveal That Light-Harvesting Complex II Loosely Bound to Photosystem II Is a Very Efficient Antenna for Photosystem I in State II
Pro-/antiinflammatory dysregulation in early psychosis: Results from a 1-year follow-Up study
Background: Previous studies indicated a systemic deregulation of the pro-/antiinflammatory balance in subjects after 6 months of a first psychotic episode. This disruption was reexamined 12 months after diagnosis to identify potential risk/ protective factors and associations with symptom severity.
Methods: Eighty-five subjects were followed during 12 months and the determination of the same pro-/antiinflammatory mediators was carried out in plasma and peripheral blood mononuclear cells. Multivariate logistic regression analyses were used to identify risk/protective factors. Multiple linear regression models were performed to detect the change of each biological marker during follow-up in relation to clinical characteristics and confounding factors.
Results: This study suggests a more severe systemic pro-/antiinflammatory deregulation than in earlier pathological stages in first psychotic episode, because not only were intracellular components of the inflammatory response increased but also the majority of soluble elements. Nitrite plasma levels and cyclooxygenase-2 expression in peripheral blood mononuclear cells are reliable potential risk factors and 15d-prostaglandin-J2 plasma levels a protection biomarker. An interesting relationship exists between antipsychotic dose and the levels of prostaglandin-E2 (inverse) and 15d-prostaglandin-J2 (direct). An inverse relationship between the Global Assessment of Functioning scale and lipid peroxidation is also present.
Conclusions: Summing up, pro-/antiinflammatory mediators can be used as risk/protection biomarkers. The inverse association between oxidative/nitrosative damage and the Global Assessment of Functioning scale, and the possibility that one of the targets of antipsychotics could be the restoration of the pro-/antiinflammatory balance support the use of antiinflammatory drugs as coadjuvant to antipsychotics
Urges to Move and Other Motivation States for Physical Activity in Clinical and Healthy Populations: A Scoping Review Protocol
[EN] Motivation for bodily movement, physical activity and exercise varies from moment to
moment. These motivation states may be “affectively-charged,” ranging from instances
of lower tension (e.g., desires, wants) to higher tension (e.g., cravings and urges).
Currently, it is not known how often these states have been investigated in clinical
populations (e.g., eating disorders, exercise dependence/addiction, Restless Legs
Syndrome, diabetes, obesity) vs. healthy populations (e.g., in studies of motor control;
groove in music psychology). The objective of this scoping review protocol is to quantify
the literature on motivation states, to determine what topical areas are represented
in investigations of clinical and healthy populations, and to discover pertinent details,
such as instrumentation, terminology, theories, and conceptual models, correlates and
mechanisms of action. Iterative searches of scholarly databases will take place to
determine which combination of search terms (e.g., “motivation states” and “physical
activity”; “desire to be physically active,” etc.) captures the greatest number of relevant
results. Studies will be included if motivation states for movement (e.g., desires, urges)
are specifically measured or addressed. Studies will be excluded if referring to motivation
as a trait. A charting data form was developed to scan all relevant documents for later data extraction. The primary outcome is simply the extent of the literature on the topic.
Results will be stratified by population/condition. This scoping review will unify a diverse
literature, which may result in the creation of unique models or paradigms that can be
utilized to better understand motivation for bodily movement and exercise.GA was supported by a fellowship from the Office of Academic Affiliations at the United States Veterans Health Administration, a Robert E. Leet and Clara Guthrie Patterson Trust Mentored Research Award, Bank of America, N.A., Trustee, and American Heart Association Grant #852679 (GA, 2021–2024).We would like to thank Melissa Eden, Ph.D. (Hanover College, IN) for her valuable assistance in refining aspects of the search strategy. Khristdman Cavalcanti helped with technical aspects of the study. Sunao Akashi Slayton, PharmD BCOP (Smilow Cancer Hospital, Yale – New Haven Hospital, CT) evaluated clinical information and provided nomenclatur
Mutational Analysis of Photosystem I of Synechocystis sp. PCC 6803: The Role of Four Conserved Aromatic Residues in the j-helix of PsaB
Photosystem I is the light-driven plastocyanin-ferredoxin oxidoreductase in the photosynthetic electron transfer of cyanobacteria and plants. Two histidyl residues in the symmetric transmembrane helices A-j and B-j provide ligands for the P700 chlorophyll molecules of the reaction center of photosystem I. To determine the role of conserved aromatic residues adjacent to the histidyl molecule in the helix of B-j, we generated six site-directed mutants of the psaB gene in Synechocystis sp. PCC 6803. Three mutant strains with W645C, W643C/A644I and S641C/V642I substitutions could grow photoautotrophically and showed no obvious reduction in the photosystem I activity. Kinetics of P700 re-reduction by plastocyanin remained unaltered in these mutants. In contrast, the strains with H651C/L652M, F649C/G650I and F647C substitutions could not grow under photoautotrophic conditions because those mutants had low photosystem I activity, possibly due to low levels of proteins. A procedure to select spontaneous revertants from the mutants that are incapable to photoautotrophic growth resulted in three revertants that were used in this study. The molecular analysis of the spontaneous revertants suggested that an aromatic residue at F647 and a small residue at G650 may be necessary for maintaining the structural integrity of photosystem I. The (P700+ - P700) steady-state absorption difference spectrum of the revertant F647Y has a ∼5 nm narrower peak than the recovered wild-type, suggesting that additional hydroxyl group of this revertant may participate in the interaction with the special pair while the photosystem I complexes of the F649C/G650T and H651Q mutants closely resemble the wild-type spectrum. The results presented here demonstrate that the highly conserved residues W645, W643 and F649 are not critical for maintaining the integrity and in mediating electron transport from plastocyanin to photosystem I. Our data suggest that an aromatic residue is required at position of 647 for structural integrity and/or function of photosystem I
Age-related cognitive decline and associations with sex, education and apolipoprotein E genotype across ethnocultural groups and geographic regions: a collaborative cohort study
Background
The prevalence of dementia varies around the world, potentially contributed to by international differences in rates of age-related cognitive decline. Our primary goal was to investigate how rates of age-related decline in cognitive test performance varied among international cohort studies of cognitive aging. We also determined the extent to which sex, educational attainment, and apolipoprotein E ε4 allele (APOE*4) carrier status were associated with decline.
Methods and findings
We harmonized longitudinal data for 14 cohorts from 12 countries (Australia, Brazil, France, Greece, Hong Kong, Italy, Japan, Singapore, Spain, South Korea, United Kingdom, United States), for a total of 42,170 individuals aged 54–105 y (42% male), including 3.3% with dementia at baseline. The studies began between 1989 and 2011, with all but three ongoing, and each had 2–16 assessment waves (median = 3) and a follow-up duration of 2–15 y. We analyzed standardized Mini-Mental State Examination (MMSE) and memory, processing speed, language, and executive functioning test scores using linear mixed models, adjusted for sex and education, and meta-analytic techniques. Performance on all cognitive measures declined with age, with the most rapid rate of change pooled across cohorts a moderate -0.26 standard deviations per decade (SD/decade) (95% confidence interval [CI] [-0.35, -0.16], p < 0.001) for processing speed. Rates of decline accelerated slightly with age, with executive functioning showing the largest additional rate of decline with every further decade of age (-0.07 SD/decade, 95% CI [-0.10, -0.03], p = 0.002). There was a considerable degree of heterogeneity in the associations across cohorts, including a slightly faster decline (p = 0.021) on the MMSE for Asians (-0.20 SD/decade, 95% CI [-0.28, -0.12], p < 0.001) than for whites (-0.09 SD/decade, 95% CI [-0.16, -0.02], p = 0.009). Males declined on the MMSE at a slightly slower rate than females (difference = 0.023 SD/decade, 95% CI [0.011, 0.035], p < 0.001), and every additional year of education was associated with a rate of decline slightly slower for the MMSE (0.004 SD/decade less, 95% CI [0.002, 0.006], p = 0.001), but slightly faster for language (-0.007 SD/decade more, 95% CI [-0.011, -0.003], p = 0.001). APOE*4 carriers declined slightly more rapidly than non-carriers on most cognitive measures, with processing speed showing the greatest difference (-0.08 SD/decade, 95% CI [-0.15, -0.01], p = 0.019). The same overall pattern of results was found when analyses were repeated with baseline dementia cases excluded. We used only one test to represent cognitive domains, and though a prototypical one, we nevertheless urge caution in generalizing the results to domains rather than viewing them as test-specific associations. This study lacked cohorts from Africa, India, and mainland China.
Conclusions
Cognitive performance declined with age, and more rapidly with increasing age, across samples from diverse ethnocultural groups and geographical regions. Associations varied across cohorts, suggesting that different rates of cognitive decline might contribute to the global variation in dementia prevalence. However, the many similarities and consistent associations with education and APOE genotype indicate a need to explore how international differences in associations with other risk factors such as genetics, cardiovascular health, and lifestyle are involved. Future studies should attempt to use multiple tests for each cognitive domain and feature populations from ethnocultural groups and geographical regions for which we lacked data
Body composition changes during a multidisciplinary treatment programme in overweight adolescents: EVASYON Study
Resumen
Introducción: el principal objetivo de las intervenciones
de pérdida de peso es disminuir la masa grasa manteniendo
la masa libre de grasa.
Objetivo: evaluar la efectividad de una intervención
multidisciplinar en la composición corporal de adolescentes
con sobrepeso, evaluados mediante diferentes métodos
de composición corporal.
Material y métodos: la intervención fue multidisciplinar
sobre el estilo de vida, aplicada durante 13 meses.
Los participantes eran adolescentes entre 13 y 16 años
con sobrepeso y obesidad. Los adolescentes (n = 156;
54,8% mujeres) fueron evaluados mediante antropometría,
absorciometría dual de rayos X y pletismografía por
desplazamiento de aire. Todas las mediciones se realizaron
al inicio, a los 2 y a los 13 meses. Se aplicaron análisis
de la covarianza de medidas repetidas y la corrección de
Bonferroni. Se realizó la imputación de las medidas antropométricas.
Resultados: se logró una alta disminución significativa
en el índice de masa grasa en los hombres después de 2 y
13 meses de intervención, según antropometría (1,16 y
1,56 kg/m2, respectivamente), absorciometría de rayos X
(1,51 y 1,91 kg/m2) y pletismografía (2,13 y 2,44 kg/m2).
Por otra parte, el mantenimiento a corto y largo plazo de
la grasa y libre de grasa en el índice de masa fue observado
por absorciometría de rayos X en las mujeres (0,94 y
0,68 kg/m2).Abstract
Introduction: the main objectives of weight-loss interventions
are to decrease fat mass while maintaining fatfree
mass.
Objective: our aim was to address effectiveness body
composition changes in overweight adolescents assessed
by different body composition methods following an obesity
intervention programme.
Material and methods: the life-style intervention was
multi-disciplinary, with 13 months follow-up. Participants
were 13-to-16 year-old overweight, or obese, Spanish
adolescents. The adolescents (n = 156; 54.8% females)
had body composition measured with anthropometry,
dual-energy X-ray absorptiometry and air-displacement
plethysmography. All measurements were made at baseline,
and after 2- and 13-months. Repeated measures analysis
of covariance to compare mean anthropometric changes
over time and the Bonferroni correction were applied.
Imputation of anthropometric measures was performed.
Results: a high significant decrease in fat mass index
was achieved in males after 2-and 13-months of intervention
as measured by anthropometry (1.16 and 1.56 kg / m2,
respectively), X-ray absorptiometry (1.51 and 1.91 kg / m2)
and plethysmography (2.13 and 2.44 kg/m2). Moreover, a
short and long-term maintenance of fat-and fat-free mass
index was observed by X-ray absorptiometry in females
(0.94 and 0.68 kg/m2)
Qualitative and quantitative evidence of motivation states for physical activity, exercise and being sedentary from university student focus groups
Motivation for physical activity and sedentary behaviors (e.g., desires, urges, wants, cravings) varies from moment to moment. According to the WANT model, these motivation states may be affectively-charged (e.g., felt as tension), particularly after periods of maximal exercise or extended rest. The purpose of this study was to examine postulates of the WANT model utilizing a mixed-methods approach. We hypothesized that: (1) qualitative evidence would emerge from interviews to support this model, and (2) motivation states would quantitatively change over the course of an interview period. Seventeen undergraduate students (mean age = 18.6y, 13 women) engaged in focus groups where 12 structured questions were presented. Participants completed the “right now” version of the CRAVE scale before and after interviews. Qualitative data were analyzed with content analysis. A total of 410 unique lower-order themes were classified and grouped into 43 higher order themes (HOTs). From HOTs, six super higher order themes (SHOTs) were designated: (1) wants and aversions, (2) change and stability, (3) autonomy and automaticity, (4) objectives and impulses, (5) restraining and propelling forces, and (6) stress and boredom. Participants stated that they experienced desires to move and rest, including during the interview, but these states changed rapidly and varied both randomly as well as systematically across periods of minutes to months. Some also described a total absence of desire or even aversion to move and rest. Of note, strong urges and cravings for movement, typically from conditions of deprivation (e.g., sudden withdrawal from exercise training) were associated with physical and mental manifestations, such as fidgeting and feeling restless. Urges were often consummated with behavior (e.g., exercise sessions, naps), which commonly resulted in satiation and subsequent drop in desire. Importantly, stress was frequently described as both an inhibitor and instigator of motivation states. CRAVE-Move increased pre-to-post interviews (p < .01). CRAVE-Rest demonstrated a trend to decline (p = .057). Overall, qualitative and quantitative data largely corroborated postulates of the WANT model, demonstrating that people experience wants and cravings to move and rest, and that these states appear to fluctuate significantly, especially in the context of stress, boredom, satiety, and deprivation
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