Sexual dimorphism in SARS-COV-2 infection

Impact of Anti-angiogenic Drugs on Severity of COVID-19 in Patients with Non-Small Cell Lung Cancer

Introduction: The 2019 coronavirus disease (COVID-19) pandemic has reshaped oncology practice, but the impact of anti-angiogenic drugs on the severity of COVID-19 in patients with non-small cell lung cancer (NSCLC) remains unclear. Patients and Methods: We carried out a retrospective study involving 166 consecutive patients with NSCLC who were positive for COVID-19, aiming to determine the effects of anti-angiogenic drugs on disease severity, as defined by severe/critical symptoms, intensive care unit (ICU) admission/intubation, and mortality outcomes. Risk factors were identified using univariate and multivariate logistic regression models. Results: Of the participants, 73 had been administered anti-angiogenic drugs (termed the anti-angiogenic therapy (AT) group), while 93 had not (non-AT group). Comparative analyses showed no significant disparity in the rates of severe/critical symptoms (21.9% vs 35.5%, P = 0.057), ICU admission/intubation (6.8% vs 7.5%, P = 0.867), or death (11.0% vs 9.7%, P = 0.787) between these two groups. However, elevated risk factors for worse outcomes included age ≥ 60 (odds ratio (OR): 2.52, 95% confidence interval (CI): 1.07-5.92), Eastern Cooperative Oncology Group performance status of 2 or higher (OR: 21.29, 95% CI: 4.98-91.01), chronic obstructive pulmonary disease (OR: 7.25, 95% CI: 1.65-31.81), hypertension (OR: 2.98, 95% CI: 1.20-7.39), and use of immunoglobulin (OR: 5.26, 95% CI: 1.06-26.25). Conclusion: Our data suggests that the use of anti-angiogenic drugs may not exacerbate COVID-19 severity in NSCLC patients, indicating their potential safe application even during the pandemic period.

The Reserve/Maximum Capacity of Melatonin's Synthetic Function for the Potential Dimorphism of Melatonin Production and Its Biological Significance in Mammals

In this article, we attempt to classify a potential dimorphism of melatonin production. Thus, a new concept of "reserve or maximum capacity of melatonin synthetic function" is introduced to explain the subtle dimorphism of melatonin production in mammals. Considering ASMT/ASMTL genes in the pseudoautosomal region of sex chromosomes with high prevalence of mutation in males, as well as the sex bias of the mitochondria in which melatonin is synthesized, we hypothesize the existence of a dimorphism in melatonin production to favor females, which are assumed to possess a higher reserve capacity for melatonin synthesis than males. Under physiological conditions, this subtle dimorphism is masked by the fact that cells or tissues only need baseline melatonin production, which can be accomplished without exploiting the full potential of melatonin's synthetic capacity. This capacity is believed to exceed the already remarkable nocturnal increase as observed within the circadian cycle. However, during aging or under stressful conditions, the reserve capacity of melatonin's synthetic function is required to be activated to produce sufficiently high levels of melatonin for protective purposes. Females seem to possess a higher reserve/maximum capacity for producing more melatonin than males. Thus, this dimorphism of melatonin production becomes manifest and detectable under these conditions. The biological significance of the reserve/maximum capacity of melatonin's synthetic function is to improve the recovery rate of organisms from injury, to increase resistance to pathogen infection, and even to enhance their chances of survival by maximizing melatonin production under stressful conditions. The higher reserve/maximum capacity of melatonin synthesis in females may also contribute to the dimorphism in longevity, favoring females in mammals.

Assessment of Anti-SARS-CoV-2 Antibodies Post-Coronavac Vaccination in the Amazon Region of Brazil

The present study evaluated the frequency of seropositivity for anti-SARS-CoV-2 (S1 and S2) total antibodies and anti-SARS-CoV-2 (receptor binding domain-RBD-S1) neutralizing antibodies in individuals vaccinated with the immunizing agent Coronavac. This was a cross-sectional study involving 358 individuals divided into two groups. Group 1 consisted of 205 volunteers who were tested for anti-SARS-CoV-2 total antibodies; group 2 consisted of 153 individuals tested for the presence of anti-SARS-CoV-2 neutralizing antibodies. Seropositivity was greater than 70% in both groups, although 17.6% and 20.9% of individuals showed no neutralizing or total antibody reactivity, respectively. The frequency of anti-SARS-CoV-2 total antibodies displayed a significantly different distribution between the sexes but not according to age. The frequency of anti-SARS-CoV-2 neutralizing antibodies was 93.3% (95% CI 68.1-99.8) in the age group from 21 to 40 years but significantly decreased with advancing age, and was 76.2% (95% CI 52.8-91.8) for 41 to 60 years, 72.5% (95% CI 62.8-80.9) for 61 to 80 years, and 46.7% (95% CI 21.3-73.4) for >80 years. Our results reveal a high prevalence of anti-SARS-CoV-2 total antibodies and anti-SARS-CoV-2 neutralizing antibodies in individuals who received both doses of the Coronavac vaccine, suggesting a lower effectiveness of the humoral immune response among those older than 60 years of age, which might be associated with senescence of the immune system.