Effect of dietary selenium and vitamin E on the biomechanical properties of rabbit bones

Summary It is generally agreed that combined deficiency of selenium and vitamin E leads to several abnormalities including Kashin-Beck disease which is an endemic and chronic degenerative osteoarthrosis. The abnormalities can be reversed by the administration of various forms of selenium and vitamin E.The present study was designed to investigate the effects of dietary selenium and vitamin E on bone tissue and on the biomechanical properties of bone. Young rabbits of both sexes were fed with either a selenium- and vitamin E-adequate diet (control group), or a selenium- and vitamin E-deficient diet or a selenium-excess diet. The selenium-deficient diet resulted in a significant decrease in plasma selenium level and the selenium-excess diet resulted in a significant increase in the plasma selenium level with respect to the corresponding control values (p<0.05). The diets did not affect the blood cell counts considerably but erythrocyte glutathione peroxidase activity increased (decreased) relatively when the plasma selenium level increased (decreased) (p<0.05). The light microscopic investigations of the bone tissues of the two experimental groups indicate that the findings of the present work are compatible with osteomalacia. The biomechanical properties of the bones from the three groups were determined experimentally with bending tests. Both the Se-and vitamin E-deficient diet and the Se-excess diet decreased the biomechanical strength of the bones significantly while the bones belonging to the control group always had the largest modulus of elasticity (p<0.05).     

Selenium improves cardiac function by attenuating the activation of NF-kappaB due to ischemia-reperfusion injury

Although selenium, an essential trace element and a component of glutathione peroxidase, is known to protect the heart from ischemia-reperfusion (I/R)-induced injury, the mechanisms of this protection are not fully understood. For this purpose, isolated rat hearts were subjected to 30 min of global ischemia followed by 30 min of reperfusion; sodium selenite (25-1,000 nM) was added in the perfusion medium 10 min prior to ischemia, as well as during reperfusion. Selenium caused a dose-dependent improvement in cardiac performance and attenuated the decrease in the ratio of reduced glutathione to oxidized glutathione, as well as the increased level of malondialdehyde in I/R heart. Elevated ratios of nuclear factor-kappaB (NF-kappaB) in particulate and cytosolic fraction and of phosphorylated NF-kappaB and total NF-kappaB in I/R hearts were reduced by selenium. Cardiac dysfunction in hearts perfused with xanthine plus xanthine oxidase mixture, as well as hydrogen peroxide, or subjected to Ca2+ paradox was also attenuated by selenium. These data suggest that selenium protects the heart against I/R injury due to its action on the redox state and deactivation of NF-kappaB in I/R hearts.     

Acceptability and Feasibility of a 13-Week Pilot Randomised Controlled Trial Testing the Effects of Incremental Doses of Beetroot Juice in Overweight and Obese Older Adults

Nitrate-rich food can increase nitric oxide production and improve vascular and brain functions. This study examines the feasibility of a randomised controlled trial (RCT) testing the effects of prolonged consumption of different doses of dietary nitrate (NO₃⁻) in the form of beetroot juice (BJ) in overweight and obese older participants. A single-blind, four-arm parallel pilot RCT was conducted in 62 overweight and obese (30.4 ± 4 kg/m²) older participants (mean ± standard deviation (SD), 66 ± 4 years). Participants were randomized to: (1) high-NO₃⁻ (HN: 2 × 70 mL BJ/day) (2) medium-NO₃⁻ (MN: 70 mL BJ/day), (3) low-NO₃⁻ (LN: 70 mL BJ on alternate days) or (4) Placebo (PL: 70 mL of NO₃⁻-depleted BJ on alternate days), for 13 weeks. Compliance was checked by a daily log of consumed BJ, NO₃⁻ intake, and by measuring NO₃⁻ and NO₂⁻ concentrations in plasma, saliva, and urine samples. Fifty participants completed the study. Self-reported compliance to the interventions was >90%. There were significant positive linear relationships between NO₃⁻ dose and the increase in plasma and urinary NO₃⁻ concentration (R² = 0.71, p < 0.001 and R² = 0.46 p < 0.001, respectively), but relationships between NO₃⁻ dose and changes in salivary NO₃⁻ and NO₂⁻ were non-linear (R² = 0.35, p = 0.002 and R² = 0.23, p = 0.007, respectively). The results confirm the feasibility of prolonged BJ supplementation in older overweight and obese adults.     

Cardiac Intervention Before Liver Transplantation

BackgroundCardiovascular complication is one of the leading causes of mortality after liver transplantation (LT). Thus, a thorough cardiac evaluation is a must before proceeding to a liver transplant surgery. Percutaneous coronary intervention (PCI) with stent and to a lesser extent coronary artery bypass grafting (CABG) are both valuable treatment options for patients with coronary artery disease.MethodsA retrospective, single-center study that included patients who underwent cardiac intervention and subsequent LT for end-stage liver disease. All patients who had PCI or CABG were included in the study.ResultsTwenty-nine adult patients out of 51 had a cardiac intervention before liver transplantation. Twenty-four patients had a diagnostic PCI, 3 patients had therapeutic PCI with stent, and 2 had failed PCI and proceeded to CABG before liver transplant. The mean age of the patients was 60.5 years. There were 24 men. All patients had cirrhosis. The 2 CABG cases were done during the same admission with a 13- and 18-day interval between the CABG and the transplantation. Both cases were live-related liver transplantation. No mortality was reported.ConclusionIn case of PCI failure, CABG may be a valuable and safe treatment option for cirrhotic patients as a preparation for liver transplantation. Live donor liver transplantation may be a good back-up for those patients in case they develop hepatic decompensation.     

Central Nervous System Effects of Ginkgo Biloba, a Plant Extract

Extracts of Ginkgo biloba (EGb) are among the most prescribed drugs in France and Germany. EGb is claimed to be effective in peripheral arterial disorders and in "cerebral insufficiency." The mechanism of action is not yet well understood. Three of the ingredients of the extract have been isolated and found to be pharmacologically active, but which one alone or in combination is responsible for clinical effects is unknown. The recommended daily dose (3 x 40 mg extract) is based more on empirical data than on clinical dose-findings studies. However, despite these, according to double-blind, placebo-controlled clinical trials, EGb has therapeutic effects, at least, on the diagnostic entity of "cerebral insufficiency," which is used in Europe as synonymous with early dementia. To determine whether EGb has significant pharmacological effects on the human brain, a pharmacodynamic study was conducted using the Quantitative Pharmacoelectroencephalogram (QPEEG(R)) method. It was established that the pharmacological effects (based on a predetermined 7.5--13.0-Hz alpha frequency band in a computer-analyzed electroencephalogram = CEEG(R)) of EGb on the central nervous system (CNS) are significantly different than placebo, and the high and low doses could be discriminated from each other. The 120-mg, but particularly the 240-mg, single doses showed the most consistent CNS effects with an earlier onset (1 h) and longer duration (7 h). Furthermore, it was established that the electrophysiological effects of EGb in CNS are similar to those of well-known cognitive activators such as "nootropics" as well as tacrine, the only marketed "antidementia" drug currently available in the United States.     

Diagnostic power of the vaginal washing-fluid prolactin assay as an alternative method for the diagnosis of premature rupture of membranes.

OBJECTIVE: The purpose of this study was to determine the reliability of the vaginal washing-fluid prolactin assay for the diagnosis of premature rupture of membranes (PROM) and to determine a diagnostic cut-off value. STUDY DESIGN: Seventy pregnant women between 11 and 40 weeks of gestation who were admitted with vaginal fluid leakage were included in the study group, and were then further subdivided into two subgroups according to amniotic fluid pooling and nitrazine paper test results. Group 1 was the 'confirmed PROM group', positive for both pooling and nitrazine (38 patients). Group 2 was the 'suspected but unconfirmed PROM group' which had possible pooling and/or nitrazine (32 patients). Seventy pregnant women between 11 and 40 weeks of gestation without any complaint and complication were included in the control group (group 3). All patients underwent vaginal washing-fluid sampling and prolactin level determination. For the statistical analysis one-way analysis of variance, Tukey multiple comparison test, chi2 test and receiver operating characteristic (ROC) curve analysis were used. RESULTS: Geometric mean values of vaginal washing-fluid prolactin levels were 616.59 microIU/ml for group 1, 23.98 microIU/ml for group 2 and 10 microIU/ml for group 3 (p < 0.0001). The optimal diagnostic cut-off value was found to be 30 microIU/ml with 95% sensitivity, 78% specificity, 84% positive predictive value, 93% negative predictive value, 87% accuracy and 11.30 relative risk. CONCLUSIONS: We recommend vaginal washing-fluid prolactin level determination as an alternative diagnostic method for PROM.     

The possible mechanisms of protocatechuic acid-induced central analgesia

It is aimed to investigate the central antinociceptive effect of protocatechuic acid and the involvement of stimulation of opioidergic, serotonin 5-HT_2A/2C, α2-adrenergic and muscarinic receptors in protocatechuic acid-induced central analgesia in mice. Time-dependent antinociceptive effects of protocatechuic acid at the oral doses of 75, 150 and 300?mg/kg were tested in hot-plate (integrated supraspinal response) and tail-immersion (spinal reflex) tests in mice. To investigate the mechanisms of action; the mice administered 300?mg/kg protocatechuic acid (p.o.) were pre-treated with non-specific opioid antagonist naloxone (5?mg/kg, i.p.), serotonin 5-HT_2A/2C receptor antagonist ketanserin (1?mg/kg, i.p.), α2-adrenoceptor antagonist yohimbine (1?mg/kg, i.p.) and non-specific muscarinic antagonist atropine (5?mg/kg, i.p.), respectively. The antinociceptive effect of protocatechuic acid was observed at the doses of 75, 150 and 300?mg/kg in tail-immersion test, at the doses of 150 and 300?mg/kg in hot-plate test at different time interval. The enhancement in the latency of protocatechuic acid-induced response to thermal stimuli was antagonized by yohimbine, naloxone and atropine in tail-immersion test, while it was antagonized only by yohimbine and naloxone pretreatments in hot-plate test. These results indicated that protocatechuic acid has the central antinociceptive action that is probably organized by spinal mediated cholinergic and opiodiergic, also spinal and supraspinal mediated noradrenergic modulation. However, further studies are required to understand how protocatechuic acid organizes the interactions of these modulatory systems. As a whole, these findings reinforce that protocatechuic acid is a potential agent that might be used for pain relief. Additionally, the clarification of the effect and mechanisms of action of protocatechuic acid will contribute to new therapeutic approaches and provide guidance for new drug development studies.     

Chronic biopsy proven post‐COVID myoendocarditis with SARS‐Cov‐2 persistence and high level of antiheart antibodies

PurposeTo study the clinical signs and mechanisms (viral and autoimmune) of myoendocarditis in the long‐term period after COronaVIrus Disease 2019 (COVID‐19).MethodsFourteen patients (nine male, 50.1 ± 10.2 y.o.) with biopsy proven post‐COVID myocarditis were observed. The diagnosis of COVID‐19 was confirmed by IgG seroconversion. The average time of admission after COVID‐19 was 5.5 [2; 10] months. An endomyocardial biopsy (EMB) of the right ventricle was obtained. The biopsy analysis included polymerase chain reaction diagnosis of viral infection, morphological, immunohistochemical (IHC) examination with antibodies to CD3, CD45, CD68, CD20, SARS‐Cov‐2 spike, and nucleocapsid antigens. Coronary atherosclerosis was ruled out in all patients over 40 years.ResultsThe new cardiac symptoms (congestive heart failure 3–4 New York Heart Association class with severe right ventricular involvement, various rhythm, and conduction disturbances) appeared 1–5 months following COVID‐19. Magnetic resonance imaging showed disseminated or focal subepicardial and intramyocardial late gadolinium enhancement, hyperemia, edema, and increased myocardial native T1 relaxation time. Antiheart antibodies levels were increased 3–4 times in 92.9% of patients. The mean left ventricular (LV) ejection fraction (EF) was 28% (24.5; 37.8). Active lymphocytic myocarditis was diagnosed in 12 patients, eosinophilic myocarditis in two patients. SARS‐Cov‐2 RNA was detected in 12 cases (85.7%), in association with parvovirus B19 DNA—in one. Three patients had also endocarditis (infective and nonbacterial, with parietal thrombosis). As a result of steroid and chronic heart failure therapy, the EF increased to 47% (37.5; 52.5).ConclusionsCOVID‐19 can lead to long‐term severe post‐COVID myoendocarditis, that is characterized by prolonged persistence of coronavirus in cardiomyocytes, endothelium, and macrophages (up to 18 months) in combination with high immune activity. Corticosteroids and anticoagulants should be considered as a treatment option of post‐COVID myoendocarditis.