Could Lower Testosterone in Older Men Explain Higher COVID-19 Morbidity and Mortalities?

The health scourge imposed on humanity by the COVID-19 pandemic seems not to recede. This fact warrants refined and novel ideas analyzing different aspects of the illness. One such aspect is related to the observation that most COVID-19 casualties were older males, a tendency also noticed in the epidemics of SARS-CoV in 2003 and the Middle East respiratory syndrome in 2012. This gender-related difference in the COVID-19 death toll might be directly involved with testosterone (TEST) and its plasmatic concentration in men. TEST has been demonstrated to provide men with anti-inflammatory and immunological advantages. As the plasmatic concentration of this androgen decreases with age, the health benefit it confers also diminishes. Low plasmatic levels of TEST can be determinant in the infection’s outcome and might be related to a dysfunctional cell Ca2+ homeostasis. Not only does TEST modulate the activity of diverse proteins that regulate cellular calcium concentrations, but these proteins have also been proven to be necessary for the replication of many viruses. Therefore, we discuss herein how TEST regulates different Ca2+-handling proteins in healthy tissues and propose how low TEST concentrations might facilitate the replication of the SARS-CoV-2 virus through the lack of modulation of the mechanisms that regulate intracellular Ca2+ concentrations.

Sex-Related Difference in the Association Between Child Neglect and the Accuracy of Body Weight Perception Among Chinese Primary Schoolchildren

Introduction: Body weight perception (BWP) directly determines weight management behaviors. Although child neglect is a well-established risk factor for managing body weight, little is known about its association with the accuracy of BWP. This study aimed to assess the cross-sectional and longitudinal associations between child neglect and BWP accuracy in primary schoolchildren, and explore how these differ based on the sex of the child.Methods: The sample included 1,063 primary schoolchildren (557 boys and 506 girls, aged 8–10 years) from a two-wave observational study between 2018 and 2019 in Wuhan, China. Child neglect and BWP were investigated using self-administered questionnaires. The accuracy of BWP was defined by comparing the BWP and actual body weight, and it was categorized into three groups—consistent, underestimated, and overestimated. Multinomial logistic regression analysis was conducted with fitting child neglect as the independent variable and the accuracy of BWP as the dependent variable.Results: The prevalence of weight misperception was ~44% at baseline (underestimation 40%; overestimation 4%) in Chinese primary schoolchildren. In the cross-sectional analysis, children with a higher level of neglect were more likely to misperceive their body weight. Moreover, there was an apparent sex-related difference that boys who experienced a higher level of neglect significantly reported more underestimation, while girls reported more overestimation. There was no significant longitudinal association between child neglect and the change in BWP accuracy.Conclusions: This study revealed that a higher level of neglect was significantly associated with underestimated BWP in boys and overestimated BWP in girls. The mechanisms of sex-related difference and whether child neglect is involved in the change in BWP, merit further investigations.

Undercutting Defeat

Although there is disagreement about the details, John Pollock’s framework for defeat is now part of the received wisdom in analytic epistemology. Recently, however, cracks have appeared in the consensus, particularly on the understanding of undercutting defeat. While not questioning the existence of undercutting defeat, Scott Sturgeon argues that undercutting defeat operates differently from rebutting. Unlike the latter, undercutting defeat, Sturgeon claims, occurs only in conjunction with certain higher-order contributions, i.e., with beliefs about the basis on which one does or would believe. Sturgeon concludes that Pollock misconceives undercutting defeat. I argue that in the case of defeat of inferential justification, undercutting defeat is a genuine phenomenon and takes roughly the shape Pollock suggests, not needing help from higher-order beliefs or justifications. However, I agree with Sturgeon that for noninferential justification the Pollockian account is in trouble. I try to explain why there should be this difference. This difference in defeaters has important implications for epistemology. In a final section, I use the defeat-related difference between inferential and noninferential justification to argue that there is less noninferential perceptual or testimonial justification than is commonly thought.

The influence of age, sex and cardiorespiratory fitness on maximal fat oxidation rate

Fat oxidation decreases age, yet, no studies have previously investigated if aging affects the maximal fat oxidation rate (MFO) during exercise in men and women differently. We hypothesized that increased age would be associated with a decline in MFO and this would be more pronounced in women due to the menopause, compared to men. In this cross-sectional study design, 435 (247/188, male /female) subjects of varying ages performed a DXA-scan, a submaximal graded exercise test and a V̇O2max test, to measure MFO and cardiorespiratory fitness (CRF) by indirect calorimetry. Subjects were stratified into 12 groups according to sex (M/F), age (<45, 45-55 and >55 years), CRF (below average (BA) and above average (AA)). Women <45 years had a higher MFO relative to fat free mass (FFM) (mg/min/kg) compared to men, regardless of CRF. However, there were no differences in MFO (mg/min/kg FFM) between men and women, in the groups between 45-55 and >55 years. In summary, we found that women <45 years display a higher MFO (mg/min/kg FFM) compared to men and that this sexual divergence is abolished after the age of 45 years. Novelty: • Maximal fat oxidation rate is higher in young women compared to men • This sex related difference is attenuated after the age of 45 years • Cardiorespiratory fitness does not influence this sex related difference