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Abstract

Coronaviruses are extremely susceptible to genetic changes due to the characteristic features of the genome structure, life cycle and environmental pressure. Their remarkable variability means that they can infect many different species of animals and cause different disease symptoms. Moreover, in some situations, coronaviruses might be transmitted across species. Although they are commonly found in farm, companion and wild animals, causing clinical and sometimes serious signs resulting in significant economic losses, not all of them have been classified by the World Organization for Animal Health (OIE) as hazardous and included on the list of notifiable diseases. Currently, only three diseases caused by coronaviruses are on the OIE list of notifiable terrestrial and aquatic animal diseases. However, none of these three entails any administrative measures. The emergence of the SARS-CoV-2 infections that have caused the COVID-19 pandemic in humans has proved that the occurrence and variability of coronaviruses is highly underestimated in the animal reservoir and reminded us of the critical importance of the One Health approach. Therefore, domestic and wild animals should be intensively monitored, both to broaden our knowledge of the viruses circulating among them and to understand the mechanisms of the emergence of viruses of relevance to animal and human health.

Abstract

Introduction: The perception of disease depends on the patient’s beliefs related to the nature of the illness, the previous personal or family experiences and his/her attitude to them. Patients try to understand and cope with health problems. The purpose of the present study was to answer the question which components of the relationship between the strategies for coping with stress and mental disease perception are moderated by gender.

Material and Methods: The study involved 98 patients with depressive disorders, anxiety disorders, schizophrenia, alcohol related disorders. The research of the variables was carried out using the COPE Inventory and Disease Perception Questionnaire.

Results: It has been noticed that in men, when their perception of the mental disorder as beneficial increases, the religious strategies for coping with stress become more frequent. Furthermore, the opposite sex pattern emerged. In the situation when an individual’s perception of the illness as a threat increased, female patients less frequently employed religious coping and planning. Furthermore, in women, when the perception of the mental disease as a weakness increases, the frequency of using emotional social support and acceptance decreases.

Conclusions: The result indicated that there are opposite patterns of gender specific coping strategy dependent on the mental illness perception.

Abstract

Introduction

Atrial fibrillation may potentially contribute to oxidative stress to a greater extent than chronic heart failure. The aim of the study was to compare the serum total antioxidant capacity and enzymatic antioxidant defence of dogs with chronic heart failure and atrial fibrillation with those of subjects with chronic heart failure and sinus rhythm and healthy controls.

Material and Methods

A total of 33 dogs were divided into three groups: dogs with chronic heart failure and atrial fibrillation (CHF + AF; n = 12), chronic heart failure and sinus rhythm (CHF + SR; n = 9), and healthy controls (n = 12). Serum total antioxidant capacity (TAC), serum CuZn-superoxide dismutase (SOD) and catalase, and plasma glutathione peroxidase (GPx) activity were determined.

Results

SOD activity and serum TAC were significantly lower in the study groups than in control animals. Catalase activity was significantly higher and plasma GPx activity significantly lower in dogs with CHF + AF compared with the CHF + SR and control dogs.

Conclusion

The results suggest that chronic heart failure in dogs significantly impacts the serum TAC and the antioxidant enzymatic defence, while plasma GPx activity is markedly lower in dogs with chronic heart failure and atrial fibrillation. The role of that imbalance needs further investigation.

Abstract

Designing proper frontend electronics is critical in the development of highly sophisticated electrode systems. Multielectrode arrays for measuring electrical signals or impedance require multichannel readout systems. Even more challenging is the differential or ratiometric configuration with simultaneous assessment of measurement and reference channels. In this work, an eight-channel frontend was developed for contacting a 2×8 electrode array (8 measurement and 8 reference electrodes) with a large common electrode to the impedance gain-phase analyzer Solartron 1260 (S-1260). Using the three independent and truly parallel monitor channels of the S-1260, impedance of trapped cells and reference material was measured at the same time, thereby considerably increasing the performance of the device. The frontend electronics buffers the generator output and applies a potentiostatic signal to the common electrode of the chip. The applied voltage is monitored using the current monitor of the S-1260 via voltage/current conversion. The frontend monitors the current through the electrodes and converts it to a voltage fed into the voltage monitors of the S-1260. For assessment of the 8 electrode pairs featured by the chip, a relay-based multiplexer was implemented. Extensive characterization and calibration of the frontend were carried out in a frequency range between 100 Hz and 1 MHz. Investigating the influence of the multiplexer and the frontend electronics, direct measurement with and without frontend was compared. Although differences were evident, they have been negligible below one per cent. The significance of measurement using the complex S-1260-frontend-electrode was tested using Kohlrausch's law. The impedance of an electrolytic dilution series was measured and compared to the theoretical values. The coincidence of measured values and theoretical prediction serves as an indicator for electrode sensitivity to cell behavior. Monitoring of cell behavior on the microelectrode surface will be shown as an example.

Abstract

Skeletal muscle mass (SMM) plays an important role in health and physical performance. Its estimation is critical for the early detection of sarcopenia, a disease with high prevalence and high health costs. While multiple methods exist for estimating this body component, anthropometry and bioelectrical impedance analysis (BIA) are the most widely available in low- to middle-income countries. This study aimed to determine the correlation between muscle mass, estimated by anthropometry through measurement of calf circumference (CC) and skeletal mass index (SMI) by BIA. This was a cross-sectional and observational study that included 213 functional adults over 65 years of age living in the community. Measurements of height, weight, CC, and SMM estimated by BIA were made after the informed consent was signed. 124 women mean age 69.6 ± 3.1 years and 86 men mean age 69.5 ± 2.9 years had the complete data and were included in the analysis. A significant positive moderate correlation among CC and SMI measured by BIA was found (Pearson r= 0.57 and 0.60 for women and men respectively (p=0.0001)). A moderate significant correlation was found between the estimation of SMM by CC and by BIA. This suggests that CC could be used as a marker of sarcopenia for older adults in settings in lower-middle-income countries where no other methods of diagnosing muscle mass are available. Although the CC is not the unique parameter to the diagnosis of sarcopenia, it could be a useful procedure in the clinic to identify patients at risk of sarcopenia.

Abstract

Sepsis is a systemic infectious disease that leads to shock, organ failure, and death and requires urgent treatment. Animal model studies of sepsis and endotoxemia have revealed that antioxidant compounds prevent the progression of multi-system organ failure and reduce death rate. In the present study aimed to establish the effect of propolis, which has been proven to have antibacterial, anti-inflammatory and antioxidant activities in recent years, on lipopolysaccharide (LPS)-induced renal damage. 40 Sprague dawley rats were randomly divided into five equal groups (n = 8): Control (0.9% NaCl), LPS (30 mg/kg), propolis (250 mg/kg), propolis + LPS, and LPS + propolis. After completion of the experimental protocol, Malondialdehyde (MDA) levels were measured using blood serum samples obtained from the rats. The kidney samples of the rats were examined histopathologically. As a result, it was determined that LPS increased MDA levels in the blood serum samples and it caused histological changes in the kidney tissue such as tubular damage, mild ischemic injury, ischemic damage in the form of vacuolization, tubular epithelial vacuolization, vascular congestion, and glomerular atrophy. Contrary to these results, MDA levels of serum decreased in the propolis + LPS, and LPS + propolis groups, and also histological findings improved. These results showed that protective effect of propolis against kidney damage caused by LPS.

Abstract

Downstream processing for recovery of microbial polyhydroxyalkanoate (PHA) biopolyesters from biomass constitutes an integral part of the entire PHA production chain; beside the feedstocks used for cultivation of PHA-production strains, this process is currently considered the major cost factor for PHA production.

Besides economic aspects, PHA recovery techniques need to be sustainable by avoiding excessive use of (often precarious!) solvents, other hazardous chemicals, non-recyclable compounds, and energy. Moreover, the applied PHA recovery method is decisive for the molecular mass and purity of the obtained product, and the achievable recovery yield. In addition to the applied method, also the PHA content in biomass is decisive for the feasibility of a selected technique. Further, not all investigated recovery techniques are applicable for all types of PHA (crystalline versus amorphous PHA) and all PHA-producing microorganisms (robust versus fragile cell structures).

The present review shines a light on benefits and shortcomings of established solvent-based, chemical, enzymatic, and mechanical methods for PHA recovery. Focus is dedicated on innovative, novel recovery strategies, encompassing the use of “green” solvents, application of classical “PHA anti-solvents” under pressurized conditions, ionic liquids, supercritical solvents, hypotonic cell disintegration for release of PHA granules, switchable anionic surfactants, and even digestion of non-PHA biomass by animals.

The different established and novel techniques are compared in terms of PHA recovery yield, product purity, impact on PHA molar mass, scalability to industrial plants, and demand for chemicals, energy, and time.

Abstract

Cereal products are the most consumed in Romania being the main contributors to daily acrylamide exposure. The paper aims to present for the first time a general situation regarding the evolution of the acrylamide levels content from cereal products, on the Romanian market, during 2017-2018 periods, as a result of legislative measures imposed by the European Union (EU). For this purpose, the levels of acrylamide in 55 selected cereal products samples were evaluated. The cereal products analyzed were grouped in biscuits, confectionery, expanded cereals, bakery products and specialties. The acrylamide content from the cereal products were detected using GC-MS/MS method. The highest level of acrylamide was found in biscuits, whereas the lowest level was determined in bakery products. The most of the cereal products samples analyzed (90.9%) was below the reference levels established by the EU Regulation for the acrylamide level from 2017 EC (2013/647/EU) and 2018 EC (2017/2158/ EU). From the 55 cereal products analyzed, only 5 biscuits samples exceeded the reference levels established by the European Commission, one in 2017 and four in 2018 period.

Abstract

The goal of this study was to determine whether the Tethapod system, which was designed to determine the impedance properties of lipid bilayers, could be used for cell culture in order to utilise micro-impedance spectroscopy to examine further biological applications. To that purpose we have used normal epithelial cells from kidney (RPTEC) and a kidney cancer cell model (786-O). We demonstrate that the Tethapod system is compatible with the culture of 10,000 cells seeded to grow on a small area gold measurement electrode for several days without affecting the cell viability. Furthermore, the range of frequencies for EIS measurements were tuned to examine easily the characteristics of the cell monolayer. We demonstrate significant differences in the paracellular resistance pathway between normal and cancer kidney epithelial cells. Thus, we conclude that this device has advantages for the study of cultured cells that include (i) the configuration of measurement and reference electrodes across a microfluidic channel, and (ii) the small surface area of 6 parallel measurement electrodes (2.1 mm2) integrated in a microfluidic system. These characteristics might improve micro-impedance spectroscopy measurement techniques to provide a simple tool for further studies in the field of the patho-physiology of biological barriers.

Abstract

Lipid disorders have been implicated in overweight and menopause. However, evidence on lipidomic analysis of fatty acids in erythrocytes of menopausal women is scarce. The aim of this study was to investigate the relationship between the body mass index within or beyond 5 years of menopause and erythrocyte fatty acid profile. This case-control study was conducted on out of 37 menopausal women total patients, 22 with body mass index ≥ 25 and 12 matched controls (body mass index <25). Experimental procedures were performed on the blood through robotic equipment for isolation of erythrocyte and cell membrane fatty acids were analyzed by using gas-liquid chromatography. Results showed that erythrocyte membranes did not change significantly in lipid composition between case and control group. However, the percentage of women who had a physiological content of saturated fatty acids was lower in case than in control group, and the percentage of women who had a physiological content of monounsaturated fatty acids and polyunsaturated fatty acids was lower in control than in case group. Woman with BMI>25 and non-physiological content of fatty acids, were richer in percentage of saturated fatty acids and poorer of monounsaturated fatty acids and polyunsaturated fatty acids than women with BMI<25. The percentage of physiological n-6/n-3 polyunsaturated ratio was lower in women with BMI>25 than in women with BMI<25. Interestingly, the percentage of patients that had physiological values of lipids beyond 5 years of menopause increased in comparison patients within 5 years of menopause. Notably, n-6/n-3 polyunsaturated fatty acids physiological ratio beyond 5 years of menopause increased in both case and control patients, indicating normalization over time. In conclusion erythrocytes fatty acids composition may be related to the body mass index and to the time from menopause.