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.

Homocysteine Plasmatic Concentration in Brain-Injured Neurocritical Care Patients: Systematic Review of Clinical Evidence

Background: Hyperhomocysteinemia (HHcy) is considered as an independent risk factor for several diseases, such as cardiovascular, neurological and autoimmune conditions. Atherothrombotic events, as a result of endothelial dysfunction and increased inflammation, are the main mechanisms involved in vascular damage. This review article reports clinical evidence on the relationship between the concentration of plasmatic homocysteine (Hcy) and acute brain injury (ABI) in neurocritical care patients. Materials and methods: a systematic search of articles in the PubMed and EMBASE databases was conducted, of which only complete studies, published in English in peer-reviewed journals, were included. Results: A total of 33 articles, which can be divided into the following 3 subchapters, are present: homocysteine and acute ischemic stroke (AIS); homocysteine and traumatic brain injury (TBI); homocysteine and intracranial hemorrhage (ICH)/subarachnoid hemorrhage (SAH). This confirms that HHcy is an independent risk factor for ABI and a marker of poor prognosis in the case of stroke, ICH, SAH and TBI. Conclusions: Several studies elucidate that Hcy levels influence the patient’s prognosis in ABI and, in some cases, the risk of recurrence. Hcy appears as biochemical marker that can be used by neuro-intensivists as an indicator for risk stratification. Moreover, a nutraceutical approach, including folic acid, the vitamins B6 and B12, reduces the risk of thrombosis, cardiovascular and neurological dysfunction in patients with severe HHcy that were admitted for neurocritical care.

Plasmatic Dimethylarginines in Dogs With Myxomatous Mitral Valve Disease

Plasmatic dimethylarginines, asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) are considered biomarkers of endothelial and renal dysfunction, respectively, in humans. We hypothesize that plasmatic concentration of dimethylarginines in dogs with myxomatous mitral valve disease (MMVD) is influenced by heart disease stage. Eighty-five client-owned dogs with MMVD, including 39, 19, and 27 dogs in ACVIM stages B1, B2, and C+D, respectively, and a control group of 11 clinically healthy dogs were enrolled. A prospective, multicentric, case-control study was performed. Each dog underwent a complete clinical examination, arterial blood pressure measurement, thoracic radiography, six-lead standard electrocardiogram, transthoracic echocardiography, CBC, biochemical profile, and urinalysis. Plasmatic concentration of dimethylarginines was determined through high-performance liquid chromatography coupled with tandem mass spectrometry. Median ADMA was significantly increased in dogs of group C+D (2.5 μmol/L [2.1–3.0]) compared to those of group B1 (1.8 μmol/L [1.6–2.3]; p < 0.001) and healthy dogs (1.9 μmol/L [1.7–2.3]; p = 0.02). Median SDMA was significantly increased in dogs of group C+D (0.7 μmol/L [0.5–0.9]) compared to those of groups B1 (0.4 μmol/L [0.3–0.5]; p < 0.001), B2 (0.4 μmol/L [0.3–0.6]; p < 0.01), and the control group (0.4 μmol/L [0.35–0.45]; p = 0.001). In the final multivariable analysis, ADMA and SDMA were significantly associated with left atrium to aorta ratio (p < 0.001), and creatinine (p < 0.001), respectively. Increased plasmatic concentrations of dimethylarginines suggest a possible role as biomarkers of disease severity in dogs with decompensated MMVD.

The Influence of Omeprazole on the Dissolution Processes of pH-Dependent Magnetic Tablets Assessed by Pharmacomagnetography

Pharmacomagnetography involves the simultaneous assessment of solid dosage forms (SDFs) in the human gastrointestinal (GI) tract and the drug plasmatic concentration, using a biomagnetic technique and pharmacokinetics analysis. This multi-instrumental approach helps the evaluation, as GI variables can interfere with the drug delivery processes. This study aimed to employ pharmacomagnetography to evaluate the influence of omeprazole on the drug release and absorption of metronidazole administered orally in magnetic-coated tablets. Magnetic-coated tablets, coated with Eudragit® E-100 (E100) and containing 100 mg of metronidazole, were produced. For the in vivo experiments, 12 volunteers participated in the two phases of the study (placebo and omeprazole) on different days to assess the bioavailability of metronidazole. The results indicated a shift as the pH of the solution increased and a delay in the dissolution of metronidazole, showing that the pH increase interferes with the release processes of tablets coated with E100. Our study reinforced the advantages of pharmacomagnetography as a tool to perform a multi-instrumental correlation analysis of the disintegration process and the bioavailability of drugs.

Determination of Efficacy of Single and Double 4.7 mg Deslorelin Acetate Implant on the Reproductive Activity of Female Pond Sliders (Trachemys scripta)

The use of long-acting gonadotropin-releasing hormone (GnRH) agonists to suppress fertility has been poorly investigated in reptiles, and the few available studies show inconsistent results. The efficacy of single and double intramuscular 4.7 mg deslorelin acetate implants in captive pond sliders (Trachemys scripta) was investigated, with 20 animals divided into three groups: a single-implant group (6 animals), a double-implant group (6 animals), and a control group (no implant). During one reproductive season (March to October), plasmatic concentration of sexual hormones (estradiol, progesterone, and testosterone) and ovarian morphometric activity via computed tomography were monitored about every 30 days. A significative decrease in the number of phase II ovarian follicles was detected in the double-implant group compared with the control group, but no significant difference was noted in the number of phase III and phase IV follicles, egg production, and plasmatic concentration of sexual hormones. Results show that neither a single nor a double deslorelin acetate implant can successfully inhibit reproduction in female pond sliders during the ongoing season, but the lower number of phase II follicles in the double-implant group can possibly be associated with reduced fertility in the following seasons.

Comparison of the Chemiluminescence Immunoassay LIAISON® with the Radioimmunoassay for Aldosterone and Renin Measurement

Determination of renin plasma levels is useful in the diagnosis of hypertension and in the therapeutic follow-up of hypertensive patients. Plasmatic concentration of renin decreases in patients with hypertension due to a primary hyperaldosteronism, contrary to renovascular hypertension where concentrations of renin and aldosterone are both elevated. Blood samples (serum, EDTA plasma) were analysed using two different chemiluminiscent methods CLIA LIAISON® and radioimmunoassay for aldosterone (IMMUNOTECH Beckman Coulter) and renin (Cisbio Bioassay) measurements were compared. We used both methods to ascertain the correlation between serum vs. EDTA plasma levels of aldosterone (RIA, CLIA) and renin (IRMA, CLIA) and to compare aldosterone to renin ratios for CLIA and for radioimmunoassay: serum aldosterone to plasma renin and plasma aldosterone to plasma renin. We compared serum aldosterone CLIA vs. RIA (rP=0.933, P<0.001) and plasma renin determined using CLIA vs. IRMA (rP=0.965, P=0.062). Furthermore, we used both methods to establish the correlation between the serum vs. plasma levels of aldosterone: RIA (rP=0.980, P<0.001); CLIA (rP=0.994, P=0.353) and serum vs. plasma levels of renin: IRMA (rP=0.948, P<0.001); CLIA (rP=0.921, P=0.011). Aldosterone (serum, plasma) to plasmatic renin ratios for CLIA (rP=0.999, P=0.286) and for radioimmunoassay (rP=0.992, P=0.025). Our data demonstrate that renin and aldosterone concentrations obtained using CLIA correlate with renin and aldosterone concentrations using radioimmunoassay methods. Correlation coefficients of pair results ranged from 0.921 to 0.994. Aldosterone (serum, EDTA plasma) to plasmatic renin ratios are comparable and any of them can be used with no significant differences found.

Factors that may interfere in estradiol-progesterone plasmatic concentration in the mid-luteal phase of hyperstimulated cycles for IVF/ICSI

Research question: We have demonstrated that plasmatic estradiol in mid-luteal phasel has prognostic value for clinical and ongoing pregnancy rate. This study investigated the possible factors that could interfere in the value of estradiol-progesterone in the mid luteal phase of cycles of IVF/ICSI Design: Retrospective study, including patients ≤39years old and with dosage of estradiol-progesterone and beta hCG 6-7 days after fresh embryo transfer and the influence of several factors or variables upon these hormones. Results: Of 189 cycles of IVF/ICSI with complete hormonal evaluation in mid-luteal phase, we studied the probably influence of ten factors upon plasmatic concentration of estradiol-progesterone. Only four factors had significant influence. Of them, the most important variable was beta hCG concentration (consequence of trophoblastic mass and number of implanted embryos), followed for number collected oocytes, and of litlle importance, scheme of final maturation with luteal phase correction (did not reach statistical difference), and day of transfer. Conclusion: The estradiol-progesterone in the mid-luteal phase, in this research, were influenced by hCG, number of collected oocytes, scheme for final maturation, but the main influence factor was the beta hCG concentration, although not had been a good correlation coefficient between these hormones, due to a large difference in the their concentrations, as seen in the high values observed on the Standard Deviation. The high percentages of clinical and ongoing pregnancies in the ≥500g/ml group, were the result of higher beta hCG levels, due to the larger number of twin pregnancy in this group.

Effects of testosterone replacement on serotonin levels in the prostate and plasma in a murine model of hypogonadism

Benign prostate hyperplasia is a dysfunctional disease with an elevated prevalence. Despite the accepted impact of aging and testosterone (TES) in its pathophysiology, its aetiology remains unknown. Recent studies described that serotonin (5-HT) inhibits benign prostate growth through the modulation of the androgen receptor, in the presence of TES. Accordingly, this work aimed to determine the impact of castration and TES replacement in plasmatic and prostatic 5-HT regulation. C57BL/6 mice were submitted to surgical castration and divided into three groups, continually exposed to either vehicle or different TES doses for 14 days. Plasmatic 5-HT concentration was measured before and after castration, and after TES reintroduction. Finally, total prostatic weight and intra-prostatic 5-HT were determined in the different groups. Our results demonstrate that mice prostate exhibits high 5-HT tissue levels and that intra-prostatic total 5-HT was independent of castration or TES reintroduction, in all studied groups. Also, 5-HT plasmatic concentration significantly increased after castration and then normalized after TES administration. Our findings revealed that mice prostate has a high 5-HT content and that total prostatic 5-HT levels do not depend on androgens’ action. On the other hand, castration induced a significant increase in plasmatic 5-HT concentration, raising the hypothesis that androgens might be regulating the production of extra-prostatic 5-HT.

Atherosclerosis as Pathogenetic Substrate for Sars-Cov2 Cytokine Storm

The severe acute respiratory syndrome coronavirus 2 (Sars-CoV-2) outbreak is a public health emergency affecting different regions around the world. The lungs are often damaged due to the presence of Sars-CoV-2 binding receptor ACE2 on epithelial alveolar cells. Severity of infection varies from complete absence of symptomatology to more aggressive symptoms, characterized by sudden acute respiratory distress syndrome (ARDS), multiorgan failure, and sepsis, requiring treatment in intensive care unit (ICU). It is not still clear why the immune system is not able to efficiently suppress viral replication in a small percentage of patients. It has been documented as pathological conditions affecting the cardiovascular system, strongly associated to atherosclerotic progression, such as heart failure (HF), coronary heart disease (CHD), hypertension (HTN) and diabetes mellitus (DM), could serve as predictive factors for severity and susceptibility during Sars-CoV-2 infection. Atherosclerotic progression, as a chronic inflammation process, is characterized by immune system dysregulation leading to pro-inflammatory patterns, including interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), and IL-1β. Reviewing immune system and inflammation profiles in atherosclerosis and laboratory results reported in severe COVID-19 infections, we hypothesized a pathogenetic correlation. Atherosclerosis may be an ideal pathogenetic substrate for high viral replication ability, leading to adverse outcomes, as reported in patients with cardiovascular factors. The level of atherosclerotic progression may affect a different degree of severe infection; in a vicious circle, feeding itself, Sars-CoV-2 may exacerbate atherosclerotic evolution due to excessive and aberrant plasmatic concentration of cytokines.

Differential diagnoses in 83 dogs with icterus

ABSTRACT: Icterus (jaundice) is a yellowish pigmentation resulting from the depositing of bilirubin in tissues due to its high plasmatic concentration. The pathogenesis of icterus includes metabolic changes or obstructed bilirubin excretion and it is classified as pre-hepatic, hepatic and post-hepatic. This study aimed to evaluate and classify different causes of icterus in dogs during post mortem examination. These dogs were examined from 2014 to 2017, using macroscopic and histologic exams as well as ancillary tests. Eighty-three dogs were examined macroscopically and microscopically. They were separated into groups of icterus types: 24 (28.9%) dogs had pre-hepatic icterus, 45 (54.2%) had hepatic, 13 (15.7%) pre-hepatic and hepatic and one (1.2%) had post-hepatic icterus. Many factors were identified as a cause of icterus, including infectious agents (51/83), neoplasms (13/83), hepatic degeneration (11/83), chronic hepatic diseases (6/83), and obstructive causes (1/87). Among the infectious causes, leptospirosis, ehrlichiosis and disorders suggestive of septicemia were diagnosed. Neoplasms associated with icterus were cholangiocarcinoma, hemangiosarcoma and lymphoma. Other causes of icterus included degenerative diseases, such as lipidosis and glycogen degeneration. Hepatic fibrosis (cirrhosis) as a chronic disease and cholelithiasis also produced icterus. PCR was performed to confirm leptospirosis and ehrlichiosis. Samples of total DNA were used to amplify a fragment of a gene from Leptospira interrogans and Ehrlichia canis. In some dogs, co-infection of these agents was detected. The classification and identification of icterus etiologies in dogs is very important due to the number of diseases with this alteration, where ante mortem diagnosis is not always easily performed when some of these conditions are present.