L-citrulline as Alternative Pharmacological Substance in Protecting Against Cardiovascular Disease

Cardiovascular disease (CVD) has contributed average 30% of global death diagnoses. Attempts of physicians to transiently relieve CVD came down to using focally targeted drugs. Struggle to find other treatment strategies is done to discover alternatives that serve to not only cure, but also prevent CVDs, or that do not require such a precise administration in order to minimize side-effects. This review would offer using L-citrulline as potential therapeutics in treating and preventing CVDs. This compound, found mostly in Citrus sp., contains chemical trait that could affect other bodily physiology, especially boosting nitric oxide (NO) production. Enhancing NO bioavailability suppresses the risk of myocardial oxidative stress due to ischemia and cardiac pressure-overload, as well as pulmonary hypertension. So, understanding of L-citrulline effects on endothelial nitric oxide synthase pathway in generation of NO and its uncoupling mechanisms may serve as fundamental treatment for oxidative stress-induced cardiovascular diseases with or without prophylaxis.

Potential Deleterious Effects of L-Citrulline Supplementation in Isoproterenol-Induced Myocardial Infarction: Focus on Nitrosative Stress

L-Citrulline shows potential activity as a supplement to prevent myocardial infarction through vasodilative and possible antioxidative effects but may be deleterious by causing nitrosative stress. This study determined the potentially deleterious effects of L-citrulline supplementation in isoproterenol-induced myocardial infarction with a focus on nitrosative stress. L-Citrulline supplementation was given orally at dosages of 300 or 600mg/kg body weight daily for 6 days. Myocardial infarction was induced in Wistar rats via subcutaneous injection of isoproterenol (85 mg/kg body weight (BW)) on day 4 and 5. Blood pressure was measured at the end of the study (day 6) and rats were sacrificed to collect heart tissue samples for a histopathological evaluation. The histopathological evaluation was done using hematoxylin and eosin staining for the myocardial damage evaluation and immunohistochemical (IHC) staining of arginase-2, inducible nitric oxide synthase (iNOS), and 3-nitrotyrosine to evaluate nitrosative stress. L-Citrulline supplementation failed to show a significant protective effect on blood pressure and exacerbated the decrease of diastolic blood pressure. Both low and high dose L-citrulline supplementation had a significant protective effect on myocardial damage compared to the isoproterenol group (p<0.01). L-Citrulline also caused increased nitrosative stress as shown by increased expression of arginase-2 and 3-nitrotyrosine on IHC staining but tended to show an ameliorative effect on iNOS expression. A significant increase in arginase-2 expression was detected between the high dose group and the other groups (p<0.01 vs. normal and isoproterenol groups; p<0.05 vs. low dose group). L-Citrulline supplementation increased 3-nitrotyrosine expression in a dose-dependent manner, which was significantly different compared to the normal group (low dose: p<0.013; high dose: p<0.003). L-Citrulline increased the production of nitrosative stress but resulted in less myocardial damage through its other effects

Regulated mitochondrial DNA replication during oocyte maturation is essential for successful porcine embryonic development.

Cellular ATP is mainly generated through mitochondrial oxidative phosphorylation, which is dependent on mitochondrial DNA (mtDNA). We have previously demonstrated the importance of oocyte mtDNA for porcine and human fertilization. However, the role of nuclear-encoded mitochondrial replication factors during oocyte and embryo development is not yet understood. We have analyzed two key factors, mitochondrial transcription factor A (TFAM) and polymerase gamma (POLG), to determine their role in oocyte and early embryo development. Competent and incompetent oocytes, as determined by brilliant cresyl blue (BCB) dye, were assessed intermittently during the maturation process for TFAM and POLG mRNA using real-time RT-PCR, for TFAM and POLG protein using immunocytochemistry, and for mtDNA copy number using real-time PCR. Analysis was also carried out following treatment of maturing oocytes with the mtDNA replication inhibitor, 2',3'-dideoxycytidine (ddC). Following in vitro fertilization, preimplantation embryos were also analyzed. Despite increased levels of TFAM and POLG mRNA and protein at the four-cell stage, no increase in mtDNA copy number was observed in early preimplantation development. To compensate for this, mtDNA appeared to be replicated during oocyte maturation. However, significant differences in nuclear-encoded regulatory protein expression were observed between BCB(+) and BCB(-) oocytes and between untreated oocytes and those treated with ddC. These changes resulted in delayed mtDNA replication, which correlated to reduced fertilization and embryonic development. We therefore conclude that adherence to the regulation of the timing of mtDNA replication during oocyte maturation is essential for successful embryonic development

Skyrmionic order and magnetically induced polarization change in lacunar spinel compounds GaV4_{4}S8_{8} and GaMo4_{4}S8_{8}: comparative theoretical study

We show how low-energy electronic models derived from the first-principles electronic structure calculations can help to rationalize the magnetic properties of two lacunar spinel compounds GaM4S8 with light (M=V) and heavy (M=Mo) transition-metal elements, which are responsible for different spin-orbit interaction strength. In the model, each magnetic lattice point was associated with the M4S4 molecule, and the model itself was formulated in the basis of molecular Wannier functions constructed for three magnetic t2 bands. The effects of rhombohedral distortion, spin-orbit interaction, band filling, and the screening of Coulomb interactions in the t2 bands are discussed in details. The electronic model is further treated in the superexchange approximation, which allows us to derive an effective spin model for the energy and electric polarization ($P$) depending on the relative orientation of spins in the bonds, and study the properties of this model by means of classical Monte Carlo simulations with the emphasis on the possible formation of the skyrmionic phase. While isotropic exchange interactions clearly dominate in GaV4S8, all types of interactions -- isotropic, antisymmetric, and symmetric anisotropic -- are comparable in the case of GaMo4S8. Particularly, large uniaxial exchange anisotropy has a profound effect on the properties of GaMo4S8. On the one hand, it raises the Curie temperature by opening a gap in the spectrum of magnon excitations. On the other hand, it strongly affects the skyrmionic phase by playing the role of a molecular field, which facilitates the formation of skyrmions, but makes them relatively insensitive to the external magnetic field in the large part of the phase diagram. We predict reversal of the magnetic dependence of $P$ in the case of GaMo4S8 caused by the reversal of direction of the rhombohedral distortion.Comment: 13 pages, 9 figure

Risks to human and animal health related to the presence of deoxynivalenol and its acetylated and modified forms in food and feed

Peer reviewedPublisher PD

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

L-citrulline as Alternative Pharmacological Substance in Protecting Against Cardiovascular Disease

Cardiovascular disease (CVD) has contributed average 30% of global death diagnoses. Attempts of physicians to transiently relieve CVD came down to using focally targeted drugs. Struggle to find other treatment strategies is done to discover alternatives that serve to not only cure, but also prevent CVDs, or that do not require such a precise administration in order to minimize side-effects. This review would offer using L-citrulline as potential therapeutics in treating and preventing CVDs. This compound, found mostly in Citrus sp., contains chemical trait that could affect other bodily physiology, especially boosting nitric oxide (NO) production. Enhancing NO bioavailability suppresses the risk of myocardial oxidative stress due to ischemia and cardiac pressure-overload, as well as pulmonary hypertension. So, understanding of L-citrulline effects on endothelial nitric oxide synthase pathway in generation of NO and its uncoupling mechanisms may serve as fundamental treatment for oxidative stress-induced cardiovascular diseases with or without prophylaxis

Reducing Loneliness in Stationary Geriatric Care with Robots and Virtual Encounters—A Contribution to the COVID-19 Pandemic

The bans on visiting nursing homes during the COVID-19 pandemic, while intended to protect residents, also have the risk of increasing the loneliness and social isolation that already existed among the older generations before the pandemic. To combat loneliness and social isolation in nursing homes, this trial presents a study during which social networks of nursing home residents and elderly hospital patients were maintained through virtual encounters and robots, respectively. The observational trial included volunteers who were either residents of nursing homes or patients in a geriatric hospital. Each volunteer was asked to fill in a questionnaire containing three questions to measure loneliness. The questionnaire also documented whether video telephony via the robot, an alternative contact option (for example, a phone call), or no contact with relatives had taken place. The aim was to work out the general acceptance and the benefits of virtual encounters using robots for different roles (users, relatives, nursing staff, facilities). Seventy volunteers with three possible interventions (non-contact, virtual encounters by means of a robot, and any other contact) took part in this trial. The frequency of use of the robot increased steadily over the course of the study, and it was regularly used in all facilities during the weeks of visitor bans (n = 134 times). In the hospital, loneliness decreased significantly among patients for whom the robot was used to provide contact (F(1,25) = 7.783, p = 0.01). In the nursing homes, no demonstrable effect could be achieved in this way, although the subject feedback from the users was consistently positive