DNA replication machineries: Structural insights from crystallography and electron microscopy.

Since the discovery of DNA as the genetic material, scientists have been investigating how the information contained in this biological polymer is transmitted from generation to generation. X-ray crystallography, and more recently, cryo-electron microscopy techniques have been instrumental in providing essential information about the structure, functions and interactions of the DNA and the protein machinery (replisome) responsible for its replication. In this chapter, we highlight several works that describe the structure and structure-function relationships of the core components of the prokaryotic and eukaryotic replisomes. We also discuss the most recent studies on the structural organization of full replisomes.

Physical Activity, Anxiety, Depression, and Adherence to Antiretroviral Therapy in People with HIV.

Physical activity (PA) levels, as well as symptoms of anxiety and depression, can affect adherence to antiretroviral therapy (ART) impacting people's health. This study aimed to evaluate the association between PA levels, clinical symptoms of anxiety and depression, and adherence to ART in people living with HIV (PLHIV). A cross-sectional study, including 125 PLHIV was conducted. Adherence to ART was assessed using the Simplified Medication Adherence Questionnaire (SMAQ). For anxiety and depression, the Hospital Anxiety and Depression Scale was applied. The level of PA was assessed using the short version of the International Physical Activity Questionnaire. SPSS version 22.0 was used for statistical analysis. The prevalence of clinical levels of anxiety and depression symptoms was 53.6% and 37.6%, respectively. Fifty-three percent presented clinical levels of depression and anxiety symptoms. Sixty-one people (48.8%) had vigorous PA levels, 36 people (28.8%) had moderate PA levels, and 28 people (22.4%) had low PA levels. According to the SMAQ, 34.5% of the patients were adherent to ART. People who performed low PA levels had more risk to develop clinical levels of depression symptoms. Clinical level of anxiety, depression, and psychological distress (PD) symptoms was found to increase the risk of nonadherence to ART.

The association between low cognitive reserve and subjective memory complaints in functionally independent older women.

BACKGROUND: Several factors have been found to defend against pathologic cognitive decline in aging (i.e., cognitive reserve [CR]); however, other factors, including subjective memory complaints (SMC) and decreased functionality are considered early indicators of underlying neurocognitive dysfunction. Despite these known associations, the relationship between the presence of CR and SMC remains equivocal. This study sought to determine the relationship between objectively measured CR and SMC in a sample of functionally independent older women. METHODS: This cross-sectional study recruited women aged ≥60 years who attended fitness or continuing education programs at the University for Seniors in Mexico City. Participants underwent a battery of physical and cognitive evaluations, including the Cognitive Reserve Questionnaire (CRQ), and were asked probing questions used to identify the presence of SMC. RESULTS: The 269 participants had a median age of 69 years; most were single (40.5 %), lived alone (32.7 %), retired (58.2 %), well-educated (≥12 years of education), and functionally independent (89.2 %). 62 % scored "high" on the CRQ, while 9.3 % scored "low". After adjusting for multiple covariates, an independent association between CRQ score and the probability to have SMC was found (adjusted OR = 0.87, 95% CI 0.80-0.95, p-value = 0.002). CONCLUSIONS: This study identified a relationship between low CR and the presence of SMC, independently of the cognitive function and motoric marker of muscle strength (i.e., low gait speed and handgrip strength) in functionally independent older women over 60y. This relationship remains independent of other variables such as age, symptoms of depression and instrumented activities of daily living.

Nutraceuticals for Complementary Treatment of Multisystem Inflammatory Syndrome in Children: A Perspective from Their Use in COVID-19.

Multisystem inflammatory syndrome in children (MIS-C) has been widely reported in some children diagnosed with SARS-CoV-2. Clinical signs of MIS-C are manifested at 2 to 4 weeks after SARS-CoV-2 infection, where elevated biomarkers of inflammation and cardiac dysfunction are the hallmark of this syndrome when infection or exposure to SARS-CoV-2 has been confirmed. However, after two years of acknowledgment, MIS-C treatment is still under research to reach safety and effectiveness in the acute phase in children. Therefore, in this review, we discuss the potential use of natural compounds with antioxidant and anti-inflammatory effects to reduce collateral damage caused by hyperinflammation in MIS-C pathology for new research in treatment and interventions.

Effect Of Exercise on Muscle Mass, Fat Mass, Bone Mass, Muscular Strength and Physical Performance in Community Dwelling Older Adults: Systematic Review and Meta-Analysis.

The demographic transition makes it necessary to establish new recommendations about the components that are most affected by aging, such as: muscle mass, fat mass, bone mass, muscle strength, and physical performance. Exercise has been identified as a factor that improves those conditions. The aim of this review is to synthetize and analyze the results of exercise interventions on muscle mass, fat mass, bone mass, strength and physical performance in community dwelling older adults (OA). A systematic search was carried out in eleven databases, using validated terms as "aged", "exercise" and others. For the meta-analysis, we differentiated by type of exercise and outcome. Twenty-nine randomized clinical trials were obtained for the review and 24 clinical trials for meta-analysis. This study identified an increase of 1.0 kg (95% Confidence Interval [CI] 0.3 -1.7) in total muscle mass (TMM) and 0.4 kg (95%CI 0.0,0.7) in appendicular muscle mass (AMM); a decrease of -3.7 kg (95% CI -5.8, -1.5) in total fat mass and -3.7% (95%CI -5.8, -1.5) in fat percentage after the resistance exercise intervention by 2-3 times per week. A -3.0% (95%CI -4.6, -1.3) decrease was observed in fat percentage after the aerobic exercise intervention. The quality of the evidence was ranked from high to very low; the risk of bias most common was performance bias and other bias. This study suggests that resistance exercise is the intervention that shows a positive effect on muscle fat mass, and bone mass. More research is needed for other exercise interventions.

Antiretroviral Therapy-Induced Dysregulation of Gene Expression and Lipid Metabolism in HIV+ Patients: Beneficial Role of Antioxidant Phytochemicals.

Human immunodeficiency virus (HIV) infection has continued to be the subject of study since its discovery nearly 40 years ago. Significant advances in research and intake of antiretroviral therapy (ART) have slowed the progression and appearance of the disease symptoms and the incidence of concomitant diseases, which are the leading cause of death in HIV+ persons. However, the prolongation of ART is closely related to chronic degenerative diseases and pathologies caused by oxidative stress (OS) and alterations in lipid metabolism (increased cholesterol levels), both of which are conditions of ART. Therefore, recent research focuses on using natural therapies to diminish the effects of ART and HIV infection: regulating lipid metabolism and reducing OS status. The present review summarizes current information on OS and cholesterol metabolism in HIV+ persons and how the consumption of certain phytochemicals can modulate these. For this purpose, MEDLINE and SCOPUS databases were consulted to identify publications investigating HIV disease and natural therapies and their associated effects.

Volviéndonos mejores: necesidad de acción inmediata ante el reto de la obesidad. Una postura de profesionales de la salud.

La creciente epidemia de obesidad ha sido uno de los retos más importantes de salud pública en México durante los últimos años. Con apoyo de la Federación Mundial de Obesidad, en 2021 formamos un grupo de profesionales para identificar y resumir las acciones prioritarias en las que puede enfocarse nuestro país para hacer frente a esta epidemia. Al proceso de desarrollo y discusión de este grupo se sumaron más de 1 000 profesionales de la salud para retomar recomendaciones de documentos y guías de alto nivel previamente publicados. En conmemoración del Día Mundial de la Obesidad, en este 2022 se presenta esta postura como insumo para el desarrollo de acciones en el ámbito profesional y de los diferentes sectores, en la que se incluyen 10 recomendaciones de acción, desde la perspectiva poblacional hasta la atención individualizada, y se enfatiza en la importancia de la participación social, de las intervenciones integrales con visión centrada en la persona y de la sostenibilidad planetaria, además de mejorar la educación y las campañas de difusión, propiciar un ambiente promotor de entornos activos y blindar de conflictos de interés los esfuerzos de prevención y control. La postura hace un llamado para abordar la obesidad de manera seria, con base en la evidencia científica, oportuna e integral, con enfoque de curso de vida, de forma ética y sensible, y sin perpetuar las barreras del estigma de peso en la sociedad.

Volviéndonos mejores: necesidad de acción inmediata ante el reto de la obesidad. Una postura de profesionales de la salud / Becoming better: the need for immediate action to address obesity. A position statement from health professionals

resumen está disponible en el texto completo

Abstract: In recent decades, the growing obesity epidemic in Mexico has become one of the most important public health challenges faced by the country. With support from the World Obesity Federation, we formed a working group in 2021 to identify and summarize priority actions that Mexico can take to face this epidemic. More than 1 000 health professionals joined the development and discussion process. Recommendations from previously published, high-level documents and guidelines were taken into account. In commemoration of World Obesity Day 2022, this statement is presented as input for health care professionals to develop actions to address obesity. The statement includes 10 recommendations that include population-level and individual-level actions. It emphasizes the importance of social participation, comprehensive interventions with a person- centered perspective, planetary sustainability, on improving education and communication campaigns, as well as fostering a built environment that promotes active living, and shielding prevention and control efforts from conflicts of interest. The statement calls for obesity to be treated seriously, based on scientific evidence, in a timely and comprehensive manner, employing a life-course and ethical approach that does not perpetuate weight stigma in society.

Prevalence of Metabolic Syndrome Among Mexican Adults.

Background: Metabolic syndrome (MetS) has increased worldwide, and since 2012, prevalence of obesity, hypertension, diabetes, and dyslipidemia has increased in Mexico. Objective: To assess the prevalence of MetS, and its relationship with sociodemographic and lifestyle factors among Mexican adults. Methods: Analytical cross-sectional study nationally representative, carried out on Mexican adults (≥20-year-old adults of both sexes; n = 4595). Socioeconomic factors, geographic area, health care coverage and previous medical diagnoses of diabetes and hypertension, and smoking were assessed. Anthropometrics, and triglyceride, total cholesterol, high-density lipoprotein cholesterol (HDL-chol), creatinine, and glucose plasma levels were measured. The ATP III MetS definition was applied. Results: A MetS prevalence of 44.2% was observed, which was higher in males than females, and increased with age, lower school level, and overweight. Hyperglycemia, hypertriglyceridemia, low HDL-chol, abdominal obesity, and hypertension were higher in people with MetS, and were associated with obesity. Conclusions: The prevalence of MetS in the Mexican adult observed in the ENSADER 2007 was high, and mainly in men than women. Specific associations of MetS with age, scholar level, and body mass index have been found. Obesity and MetS were associated.

Potential Mechanisms of the Improvement of Glucose Homeostasis in Type 2 Diabetes by Pomegranate Juice.

Pomegranate is a polyphenol-rich fruit. Studies have shown that extracts prepared from its juice or from different parts of the pomegranate plant have various biological activities including antioxidant, antimicrobial, anti-inflammatory, anticarcinogenic, cardioprotective, and antidiabetic. The therapeutic potential has been attributed to various phytochemicals, including ellagic acid, punicic acid, flavonoids, anthocyanidins, anthocyanins, flavonols, and flavones. This review focuses on the scientific evidence of pomegranate juice as hypoglycemic, emphasizing the chemical composition and the possible mechanisms of action associated with this effect. Studies were identified using the PubMed, Scopus, and ISI Web of Science databases to identify relevant articles focused on the hypoglycemic effect of pomegranate juice. The physiological responses to pomegranate juice are reported here, including a decrease of oxidative stress damage, an increase of insulin-dependent glucose uptake, maintenance of ß-cell integrity, inhibition of nonenzymatic protein glycation, an increase of insulin sensitivity, modulation of peroxisome proliferator-activated receptor-gamma, inhibition of α-amylase, inhibition of α-glucosidase and dipeptidyl peptidase-4, and decreases in inflammation. Overall, we found a significant hypoglycemic effect of pomegranate in in vitro and in vivo studies and we summarize the potential mechanisms of action.

The Paradoxical Effect of Living Alone on Cognitive Reserve and Mild Cognitive Impairment among Women Aged 60+ in Mexico City.

An elderly person who lives alone must often be autonomous and self-sufficient in daily living activities. We explored if living alone and marital status were associated with mild cognitive impairment and low cognitive reserve in a sample of Mexican women aged 60+ attending continuing education courses using a cross-sectional design. Objective cognitive functions were assessed using the MMSE and Blessed Dementia Scale. We administered the Cognitive Reserve Questionnaire. Independence skills were assessed with the Katz index and Lawton index. Multivariate logistic regression analysis was used. We recruited 269 participants (x¯ = 69.0 ± 5.8 years). Single, widowed, separated, and divorced women comprised 73% of the participants. A third lived alone and 84% had completed high school. Mild cognitive deficit was observed among 24.5-29.0%; the upper range for cognitive reserve was 61.7%. Living alone versus living with someone was associated with cognitive impairment (OR = 0.51, p = 0.04) and with low to medium cognitive reserve (OR = 0.51, p = 0.02) after adjusting for confounding variables. Living alone was an independent factor associated with a lower probability of displaying mild cognitive impairment and a higher probability of displaying high cognitive reserve. Women living alone in this study had a more robust cognitive framework and had built their own support networks.

Association between the Use of Health Services, Cardiovascular Risk Factors and Metabolic Syndrome in Mexican Adults.

Background: The use of health services is a complex behavioral phenomenon affected by multiple factors (availability, distance, cost, quality, attitudes, cultural beliefs, socioeconomic characteristics, and individuals' self-perception of health). Mexico has a segmented health system, and the access to it depends on the labor insertion and the population's ability to pay. Objective: To assess association between use of health services and cardiovascular and metabolic syndrome risk factors among Mexican adults. Methods: Analytical cross-sectional nationally representative study carried out on Mexican adults (≥20-year-old adults of both sexes; n = 4595). Socioeconomic factors, geographic area, health care coverage, information about the use of health services, previous medical diagnoses of diabetes and hypertension, and smoking were assessed. Anthropometrics, triglyceride, total cholesterol, HDL-cholesterol, and glucose plasma levels were measured. Metabolic syndrome (MetS) and cardiovascular risk factors were assessed. Prevalences were expressed in terms of percentages, and significant differences were calculated using χ2 test. Univariate and multivariate analysis was performed to evaluate the association between the use of health services and cardiovascular risk factors and sociodemographic variables. Results: The probability of using health services is higher and more significant in subjects with obesity, diabetes (OR (95% CI): 1.73 (1.49-2.00; p < 0.001), hypertension (OR (95% CI): 1.29 (1.14-1.45; p < 0.001), hypertriglyceridemia (OR (95% CI): 1.30 (1.15-1.46; p < 0.001), and in those with hypercholesterolemia (OR (95% CI): 1.23 (1.03-1.39; p = 0.001). Conclusions: Among health service users, there is a positive significant association between the use of health services and the presence of metabolic syndrome, obesity, diabetes, hypertension, hypertriglyceridemia, and hypercholesterolemia.

Current Therapies Focused on High-Density Lipoproteins Associated with Cardiovascular Disease.

High-density lipoproteins (HDL) comprise a heterogeneous family of lipoprotein particles divided into subclasses that are determined by density, size and surface charge as well as protein composition. Epidemiological studies have suggested an inverse correlation between High-density lipoprotein-cholesterol (HDL-C) levels and the risk of cardiovascular diseases and atherosclerosis. HDLs promote reverse cholesterol transport (RCT) and have several atheroprotective functions such as anti-inflammation, anti-thrombosis, and anti-oxidation. HDLs are considered to be atheroprotective because they are associated in serum with paraoxonases (PONs) which protect HDL from oxidation. Polyphenol consumption reduces the risk of chronic diseases in humans. Polyphenols increase the binding of HDL to PON1, increasing the catalytic activity of PON1. This review summarizes the evidence currently available regarding pharmacological and alternative treatments aimed at improving the functionality of HDL-C. Information on the effectiveness of the treatments has contributed to the understanding of the molecular mechanisms that regulate plasma levels of HDL-C, thereby promoting the development of more effective treatment of cardiovascular diseases. For that purpose, Scopus and Medline databases were searched to identify the publications investigating the impact of current therapies focused on high-density lipoproteins.

Prevalence of metabolic syndrome among elderly Mexicans.

BACKGROUND: One of the most prevalent chronic diseases among elderly population is the Metabolic Syndrome (MetS). The aim of this study was to assess the prevalence of MetS and associated factors among Mexican elderly people. SUBJECTS: Cross-sectional survey carried out in Mexico (2007). A random sample (n=516) of the elderly population (≥65years; 277 female, 239 male) was interviewed. Anthropometric and analytical measurements, and a general questionnaire incorporating questions related to socio-demographic and life-style factors were used. MetS definition AHA/NHLBI/IDF was applied. RESULTS: The prevalence of MetS in the elderly (≥65years) was of 72.9% (75.7% men; 70.4% women). Participants with values above MetS cut-off points were 92.4% (hypertension), 77.8% (hypertriglyceridemia), 77.1% (low HDL-cholesterol), 71.1% (hyperglycaemia), and 65.4% (central obesity). People with MetS showed higher values of anthropometric and biochemical variables than those without MetS, except for the height, cholesterol and creatinine. Mid-high education level (9-12 years), no smokers and former smokers, and Central-Western inhabitants of Mexico were associated with MetS components. BMI status was the main determinant of MetS prevalence and MetS components. CONCLUSION: The reported prevalence of MetS among the elderly Mexican population was higher than those previously obtained in the geographical area, showing a major public health problem in Mexican elders.

Correlación de los hallazgos histopatológicos con las variables ultrasonográficas del endometrio conforme al peso corporal y distribución del tejido adiposo en la posmenopausia / Correlation of histopathologic findings with ultrasonographic variables of endometrium in relation with body weight and adipose tissue distribution in postmenopause

El objetivo de este trabajo fue correlacionar los hallazgos histopatologícos y las variables ultrasonográficas del endometrio en relación al peso corporal y distribución del tejido adiposo, en dos grupos de mujeres: uno con sangrado uterino posmenopáusico y otro bajo terapia hormonal de reemplazo (THR). fueron estudiadas 31 mujeres posmenopáusicas divididas en dos grupos: I. mujeres con sangrado uterino posmenopáusico (n= 19) y II. mujeres con THR (estrógenos conjugados y clormadinona) (n= 12). En ambos grupos se realizó el mismo día ultrasonido transvaginal previo a la biopsia de endometrio (BE). La BE se tomó en el grupo I el día que acudieron a consulta refiriendo sangrado y en el grupo II en el día 21 del ciclo de THR. Se observó que en el grupo I existió correlación significativa entre el peso corporal y los hallazgos histológicos y entre la refringencia del endometrio y los hallazgos histológicos. En el grupo II hubo correlación significativa entre la distribución de tejido adiposo y la refringencia del endometrio y entre el espesor endometrial y los hallazgos histológicos. Por lo que se puede concluir que en la mujer con sangrado posmenopáusico el peso corporal influye sobre los hallazgos histológicos y la refringencia está en relación del hallazgo histológico, mientras que en aquellas con THR es más importante la distribución del tejido adiposo sobre la refringencia del endometrio y el espesor endometrial tiene relación con los hallazgos histológicos.