Deficiency of Vitamin D, a Major Risk Factor for SARS-CoV-2 Severity.

BACKGROUND: The SARS-CoV-2 outbreak started in March 2020 with more than 120,552,261 cases at present and having caused over 2,667,248 deaths worldwide at the time this paper was written. The clinical signs of SARS-CoV-2 infection are especially evident in the respiratory and cardiovascular systems. Patients can be asymptomatic or present mild respiratory symptoms to severe acute lung injury leading to multiorgan failure and death. The study aims to assess the levels of serum 25-hydroxyvitamin D (25-(OH)-D) in 20 hospitalized patients infected with SARS-CoV-2 and 20 deceased people and to analyze the influence of vitamin D status on the severity of their disease. METHODS: The present study was conducted on 40 patients who tested positive for SARS-CoV-2 infection. They were divided into two groups: 20 patients admitted to the "Victor Babes" Hospital of Infectious Diseases and 20 postmortem cases autopsied at the Institute of Legal Medicine Timisoara, Romania. During the autopsy, blood and bronchial fluid samples were collected for the laboratory. Automate Viral RNA extraction was performed on the Maxwell 48 RSC Extraction System (Promega, USA) using the Maxwell RSC Viral Total Nucleic Acid Purification kit (Promega, USA). After RNA extraction, the samples were amplified on a 7500 real-time PCR (Applied Biosystems, USA) using the genesig® Real-Time PCR Assay 2G (Primer Design, UK). RESULTS: The living and deceased patients selected for the research presented decreased vitamin D levels, which are associated with increased levels of D-dimers, C reactive protein (CRP), and interleukin-6 (IL-6). These patients had a severe form of the SARS-CoV-2 disease, which led to death. CONCLUSIONS: We conclude that deficiency of vitamin D in patients infected with SARS-CoV-2 presents a major risk factor related to the evolution and severity of the disease.

Beta-blockers for the treatment of arrhythmias: Bisoprolol - a systematic review.

OBJECTIVES: Beta-blockers have long been successfully used for the treatment of both supraventricular and ventricular arrhythmias. However, differences exist between their chemical structure, pharmacokinetic and pharmacodynamic properties (absorption, bioavailability, metabolism, hydrophilic or lipophilic character, selective or non-selective nature, the presence or absence of intrinsic sympathomimetic activity), which may confer different antiarrhythmic properties to different beta-blockers. The aim of this study was to analyze the current existing evidence for bisoprolol for the treatment of both supraventricular and ventricular arrhythmias. MATERIAL AND METHODS: Using the keywords "bisoprolol" and "arrhythmias" or "atrial fibrillation" or "ventricular tachycardia" or "premature ventricular complexes" or "ventricular fibrillation", the Medline database was searched for articles in English or French until April 2020 assessing the role of bisoprolol in the treatment of arrhythmias. Data was then analyzed according to the type of arrhythmia treated and the quality of evidence using the GRADE approach. RESULTS: A total of 325 studies were identified, of which 28 were considered relevant to the current topic. Among these studies, 19 assessed the role of bisoprolol for the treatment of supraventricular arrhythmias, 8 its role in treating ventricular arrhythmias and 1 its role in supraventricular and ventricular arrhythmias. The quality of evidence varied from low (7 studies) to high (5 studies). CONCLUSION: Current evidence exists supporting the use of bisoprolol for the treatment of supraventricular arrhythmias, especially for rate control during atrial fibrillation. Evidence also exists for its efficacy in the treatment of ventricular arrhythmias, both in primary and in secondary prevention.

An alternative design approach for Fractional Order Internal Model Controllers for time delay systems.

INTRODUCTION: Fractional Order Internal Model Control (FO-IMC) extends the capabilities of the classical IMC approach into the generalized domain of fractional calculus. When dealing with processes that exhibit time delays, implementation of such controllers in a classical feedback loop requires the approximation of the fractional order terms, as well as of the corresponding time delays. OBJECTIVES: The present study proposes an alternative design procedure of FO-IMC controllers based on a novel approximation method of the process time delay, proving the efficiency of the proposed method and its suitability for time delay systems. METHODS: The generalized IMC control laws are obtained analytically, based on a novel approximation of time delay, the Non-Rational Transfer Function approach. RESULTS: Several numerical examples are chosen to illustrate the efficiency of the proposed approach. In addition, a vertical take-off and landing unit exhibiting second order plus time delay dynamics is chosen to experimentally validate the proposed control strategy. The obtained results are used to compare the proposed tuning strategy with a popular FO-IMC tuning approach, based on the Taylor series approximation of the time delay. CONCLUSION: All the chosen examples, both numerical and experimental ones, validate the proposed method. The overall closed loop results obtained with the proposed approach demonstrate an improved performance compared to the existing method. Ultimately, the purpose of the paper to provide an alternative design strategy that extends the existing FO-IMC control field is reached.

Mathematical modelling with experimental validation of viscoelastic properties in non-Newtonian fluids.

The paper proposes a mathematical framework for the use of fractional-order impedance models to capture fluid mechanics properties in frequency-domain experimental datasets. An overview of non-Newtonian (NN) fluid classification is given as to motivate the use of fractional-order models as natural solutions to capture fluid dynamics. Four classes of fluids are tested: oil, sugar, detergent and liquid soap. Three nonlinear identification methods are used to fit the model: nonlinear least squares, genetic algorithms and particle swarm optimization. The model identification results obtained from experimental datasets suggest the proposed model is useful to characterize various degree of viscoelasticity in NN fluids. The advantage of the proposed model is that it is compact, while capturing the fluid properties and can be identified in real-time for further use in prediction or control applications. This article is part of the theme issue 'Advanced materials modelling via fractional calculus: challenges and perspectives'.

Extensive Fatty Replacement of the Pancreas (Pancreatic Lipomatosis) in a Dog.

A 12-year-old neutered female mixed-breed dog was referred for occasional vomiting that had increased progressively in frequency over the past 3 months. Palpation of the abdomen revealed a firm mass of unknown aetiology, located within the cranial to mid abdomen, while abdominal surgical exploration revealed a well-defined abdominal mass of pancreatic origin. The pancreatic mass caused lateral displacement of the duodenum as well as medial displacement of the pylorus, resulting in impairment of pyloric outflow. Further examination revealed a firm, poorly vascularized and coarsely lobulated structure. The histopathological findings were consistent with severe pancreatic lipomatosis and atrophy. Immunohistochemically, the remnant pancreatic cells were positive for cytokeratins AE1/AE3 and glucagon, and negative for insulin. Routine follow-up with the referring veterinarian showed no evidence of postoperative complications, but the dog continued to deteriorate further and died despite medical management. Pancreatic lipomatosis is a rare condition in small animal practice. The aetiology or predisposing factors have not been identified in animals.

Cardiovascular profiles of scleroderma patients with arrhythmias and conduction disorders.

Introduction Arrhythmias and conduction disorders are common among patients with scleroderma. Their early identification is important, since scleroderma patients with arrhythmias have a higher mortality risk compared with scleroderma patients without arrhythmias. The aim of this study was to characterize the cardiovascular profiles of scleroderma patients with different types of arrhythmias and conduction disorders. Methods One hundred and ten consecutive patients with a diagnosis of systemic sclerosis according to the ACR criteria were included in the study. Patients underwent a 12-lead ECG and a 24-hour Holter ECG monitoring for arrhythmias and conduction disorders identification. Blood sample testing, echocardiography, spirometry, chest X-ray and, when considered appropriate, high resolution chest CT were also performed. A subgroup of 21 patients underwent NT-pro BNP level measurements. Patients' clinical and para-clinical characteristics were compared according to the presence or absence of arrhythmias and conduction disorders. Results The prevalence of arrhythmia and conduction disturbances was 60.9%. Patients with such disorders were older (54.4 ± 13.3 vs. 49.7 ± 10.1 years, p=0.05), had a higher prevalence of pulmonary hypertension (p=0.008), valve disease (p < 0.001), especially mitral and tricuspid regurgitation, chamber enlargement on echocardiography (left atrial and right ventricular, p = 0.012 and 0.005, respectively) as well as higher NT-pro BNP levels: 265.5 ± 399.7 vs. 163 ± 264.3 pg/ml, p=0.04. Conclusion Arrhythmias and conduction disorders are common in patients with scleroderma. Patients with such disorders are older, have a higher prevalence of pulmonary hypertension, more severe mitral and tricuspid regurgitation, left atrial and right ventricular dilation on echocardiography.

[Gastric necrosis, rare complication after laparoscopic gastric banding--case report]. / Necroza gastrica, complicatie rara dupa gastric banding--prezentare de caz.

In the last years, laparoscopic gastric banding has become a popular surgical option for morbidly obese patients, because of the minimally invasive and easy surgical technique, its reversibility, and the possibility to calibrate the stoma. Gastric necrosis, as a complication of laparoscopic gastric banding, has been rarely reported. We present the case of a 34 -year-old pregnant patient (18 week pregnancy) with 5 days history of abdominal pain. She had undergone laparoscopic adjustable gastric banding 24 months earlier with a body mass index (BMI) of 43 kg/m2. Diagnostic workup was very difficult because the patient was pregnant and we can use only ultrasonography and clinically signs. After initial conservative management, the patient underwent urgent surgery and we found an anterior gastric prolapse through the band with necrosis of the herniated stomach. A longitudinal (sleeve) gastrectomy was performed. The postoperative evolution was god and the patient left our clinic after 9 day. Emergency sleeve gastrectomy could represent a good option to treat, in a safe way.

Ethanol stimulates the formation of free oxygen radicals in the brain of newborn rats.

The possibility of free radicals effects in ethanol-induced teratogenesis was investigated by determining the production of reactive oxygen species (ROS) in the neonatal rat brain. Ethanol 33% was administered daily, by i.p. injection from day 8 of pregnancy to day 6-8 p.n. The presence of the lipid peroxidation process (indicating ROS formation) was determined by using a qualitative and quantitative analysis of malondialdehyde (MDA). An important increase of MDA was found suggesting the involvement of ROS in the pathogenetic mechanism of alcohol embryo- and fetopathy.

The influence of beer, cognac and ethanol upon the follicular state of mouse ovaries on day 4 of pregnancy.

There exist few experimental and anatomo-clinical data with respect to the effect of preconceptional and intragestional ethanol (alcoholic beverages) intake upon ovarian morpho-physiology. In order to obtain an insight into this aspect of alcohol embryo- and fetopathy, the influence of acute intoxication with beer and cognac on the background of chronic intake (in mice) and of chronic ethanol intake (in rats) upon ovarian morphology was studied, on day 4 (mice) and 5 (rats), respectively. The following characteristics were registered: the percentage of various follicular developmental stages (I-V), of atreting follicles, of preantral and antral follicles, of follicles with precocious antrogenesis. Significant changes were round in mice with respect to antral and mature follicles (lower percentage induced by beer) and concerning atreting follicles (lower percentage induced by cognac). On the other hand, precocious antrogenesis (during follicular stage II) occurred by far more frequently than expected.