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Toxoplasma gondii in pork and pigs in Serbia – a real food safety hazard
Get PDFInfection with the apicomplexan protozoon Toxoplasma gondii is one of the most prevalent parasitic zoonotic infections globally, with existing seroprevalences varying between continents, countries, and even within countries and between individual communities. It is estimated that one third of the world's human population is infected with T. gondii, with many studies showing that the dominant mode of infection is consumption of undercooked meat harbouring T. gondii tissue cysts. Prevalences of infection in food animals in different countries range from 0 to 93%. Because of the absence of clinical symptoms in infected animals, and the unfeasibility of rapid and unequivocal detection of microscopic tissue cysts in pork, infected pigs remain unrecognized, and their meat becomes an essential source of infection for humans. The data on T. gondii infection in pigs in Serbia from several studies, as well as on the detection of the parasite in different food categories, from fresh pork to heat-treated products, are discussed
Regulation of the mesenchymal stem cell fate by interleukin-17: Implications in osteogenic differentiation
Get PDFBone regeneration is a tightly regulated process that ensures proper repair and functionality after injury. The delicate balance between bone formation and resorption is governed by cytokines and signaling molecules released during the inflammatory response. Interleukin (IL)-17A, produced in the early phase of inflammation, influences the fate of osteoprogenitors. Due to their inherent capacity to differentiate into osteoblasts, mesenchymal stem/stromal cells (MSCs) contribute to bone healing and regeneration. This review presents an overview of IL-17A signaling and the leading cellular and molecular mechanisms by which it regulates the osteogenic differentiation of MSCs. The main findings demonstrating IL-17A’s influence on osteoblastogenesis are described. To this end, divergent information exists about the capacity of IL-17A to regulate MSCs’ osteogenic fate, depending on the tissue context and target cell type, along with contradictory findings in the same cell types. Therefore, we summarize the data showing both the pro-osteogenic and anti-osteogenic roles of IL-17, which may help in the understanding of IL-17A function in bone repair and regeneration
Classification of time series of temperature variations from climatically homogeneous regions based on long-term persistence
No full textWe used detrended methods for scaling analysis (DFA2 and DMA) and wavelet transform spectral analysis (WTS) to characterize long-term persistence (LTP) properties of temperature anomalies time series from observational stations from climatically and topologically homogeneous HadCRUT4 grid cells. We were interested to investigate the validity of the expectation that their LTP scaling properties remain preserved in the process of HadCRUT4 spatially interpolated and bias adjusted averaging, which was indeed the case in our selection. We additionally utilized the Hurst space analysis (HSA), a methodological solution that we recently developed, to classify climatic records from our dataset according to their LTP character and similarity of their WTS cyclical presentation. We were able to use HSA to observe four distinct patterns of climate dynamic behaviour according to the 'preferred' characteristic that those do not 'belong to the ocean'. In this way, our results suggested that there probably exists a necessity to examine cycles in climate records as important elements of natural variability. To illustrate how the procedure developed in this article can be extended, we used HSA developed by the use of a dataset from climatically and topologically homogeneous regions to classified time series of teleconnection indices that may have influence on their regional climate. HSA can be further systematically utilized in this way, to link LTP properties of temperature anomalies with their possible spatially remote sources
Mitochondrial Function and Dysfunction in Dilated Cardiomyopathy
Get PDFCardiac tissue requires a persistent production of energy in order to exert its pumping function. Therefore, the maintenance of this function relies on mitochondria that represent the "powerhouse" of all cardiac activities. Mitochondria being one of the key players for the proper functioning of the mammalian heart suggests continual regulation and organization. Mitochondria adapt to cellular energy demands via fusion-fission events and, as a proof-reading ability, undergo mitophagy in cases of abnormalities. Ca2+ fluxes play a pivotal role in regulating all mitochondrial functions, including ATP production, metabolism, oxidative stress balance and apoptosis. Communication between mitochondria and others organelles, especially the sarcoplasmic reticulum is required for optimal function. Consequently, abnormal mitochondrial activity results in decreased energy production leading to pathological conditions. In this review, we will describe how mitochondrial function or dysfunction impacts cardiac activities and the development of dilated cardiomyopathy
Insight into the Biological Activity of Hennosides-Glucosides Isolated from Lawsonia inermis (henna): Could They Be Regarded as Active Constituents Instead
Get PDFHenna is the current name of the dye prepared from the dry leaf powder of Lawsonia inermis (Lythraceae). Several studies have focused on the chemistry and pharmacology of the henna dyeing active compound, lawsone, obtained from the main constituents of leaves, hennosides, during the processing of plant material. However, knowledge regarding the biological activity of hennosides is largely lacking. In this paper, the redox activity of three hennoside isomers is reported. The pro-oxidative activity was confirmed by their ability to induce mild lysis of erythrocytes and to increase the level of methemoglobin at the concentration gt = 500 mu g/mL. The antioxidant activity of hennosides (concentration gt = 100 mu g/mL) was determined by FRAP and ABTS assays. At concentration of 500 mu g/mL, antioxidant activity of hennoside isomers was equivalent to 0.46 +/- 0.08, 0.62 +/- 0.28 and 0.35 +/- 0.03 mM FeSO4 x 7H(2)O, and 0.15 +/- 0.01, 0.30 +/- 0.01 and 0.09 +/- 0.01 mM Trolox. Hennosides at 100 mu g/mL concentration did not influence viability of human breast cancer cell lines MDA231 and MCF-7 and primary human peripheral blood and periodontal ligament-mesenchymal stem cells, but produced a modest increase in concentration of antioxidants in the cell culture supernatants. The evidenced antioxidant and pro-oxidant activities indicate their potential to act as redox balance regulator, which opens up the possibility of using hennosides in commercial phytomedicines
Maternal Anti-Toxoplasma Treatment during Pregnancy Is Associated with Reduced Sensitivity of Diagnostic Tests for Congenital Infection in the Neonate
Get PDFNeonatal diagnosis of congenital toxoplasmosis is based on a combination of serological and molecular tests. Maternal screening and treatment differ according to national policies and may impact the sensitivity of diagnostic methods in infants at birth. In this multicenter study, 115 neonates born to 61 treated (53%) and 54 (47%) untreated women were retrospectively included in three centers (France, Serbia, and the United States) to assess the impact of maternal anti-Toxoplasma treatment on the performance of neonatal workup at birth (neosynthesized anti-Toxoplasma IgM, IgA, and IgG and quantitative PCR [qPCR]) using univariate and multivariate approaches. Independently of the time of maternal seroconversion, the serological techniques were impacted differently by maternal treatment. The detection of IgM by immunosorbent agglutination assay (ISAGA) and Western blotting (WB) dropped from 90.7% and 88.2% in untreated neonates to 533% and 51.9% in treated neonates (P lt 0.05), whereas IgM enzyme-linked immunosorbent assay (ELISA) and IgA ISAGA were not significantly affected by maternal treatment. A 2-fold reduction in the sensitivity of neosynthesized IgG by WB was also observed in the case of treatment during pregnancy (37.7% versus 82.3%). Interestingly, the effect of treatment was shown to be duration dependent, especially for IgM detection, when the treatment course exceeded 8 weeks, whatever the therapy. The sensitivity of Toxoplasma PCR in blood was also lowered by maternal treatment from 39.1% to 23.2%. These results highlight that anti-Toxoplasma therapy during pregnancy may set back biological evidence of neonatal infection at birth and underline the need for a careful serological follow-up of infants with normal workup.This is the peer-reviewed version of the article: Guegan, H.; Štajner, T.; Bobić, B.; Press, C.; Olariu, R. T.; Olson, K.; Srbljanović, J.; Montoya, J. G.; Đurković-Đaković, O.; Robert-Gangneux, F. Maternal Anti-Toxoplasma Treatment during Pregnancy Is Associated with Reduced Sensitivity of Diagnostic Tests for Congenital Infection in the Neonate. Journal of Clinical Microbiology 2021, 59 (2). [https://doi.org/10.1128/JCM.01368-20
Transcranial direct current stimulation (Tdcs) for memory enhancement
No full textMemory enhancement is one of the great challenges in cognitive neuroscience and neurorehabilitation. Among various techniques used for memory enhancement, transcranial direct current stimulation (tDCS) is emerging as an especially promising tool for improvement of memory functions in a non-invasive manner. Here, we present a tDCS protocol that can be applied for memory enhancement in healthy-participant studies as well as in aging and dementia research. The protocol uses weak constant anodal current to stimulate cortical targets within cortico-hippocampal functional network engaged in memory processes. The target electrode is placed either on the posterior parietal cortex (PPC) or the dorsolateral prefrontal cortex (DLPFC), while the return electrode is placed extracranially (i.e., on the contralateral cheek). In addition, we outline a more advanced method of oscillatory tDCS, mimicking a natural brain rhythm to promote hippocampus-dependent memory functions, which can be applied in a personalized and non-personalized manner. We present illustrative results of associative and working memory improvement following single tDCS sessions (20 minutes) in which the described electrode montages were used with current intensities between 1.5 mA and 1.8 mA. Finally, we discuss crucial steps in the protocol and methodological decisions that must be made when designing a tDCS study on memory
Nitric Oxide Mediation in Hydroxyurea and Nitric Oxide Metabolites’ Inhibition of Erythroid Progenitor Growth
Get PDFIn several systems, hydroxyurea has been shown to trigger nitric oxide (NO) release or activation of NO synthase (NOS). To elucidate this duality in its pharmacological effects, during myelosuppression, we individually examined hydroxyurea’s (NO releasing agent) and NO metabolites’ (stable NO degradation products) effects on erythroid colony growth and NOS/NO levels in mice using NO scavenger 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (PTIO). Hydroxyurea and nitrite/nitrate decreased the bone marrow cellularity that was blocked by PTIO only for the NO metabolites. Hydroxyurea inhibition of colony-forming unit-erythroid (CFU-E) formation and reticulocytes was reversed by PTIO. Moreover, hydroxyurea, through a negative feedback mechanism, reduced inducible NOS (iNOS) expressing cells in CFU-E, also prevented by PTIO. Nitrate inhibition of burst-forming units-erythroid (BFU-E) colony growth was blocked by PTIO, but not in mature CFU-E. The presented results reveal that NO release and/or production mediates the hydroxyurea inhibition of mature erythroid colony growth and the frequency of iNOS immunoreactive CFU-E
Is Inhibitory Control Related to Conflict in Reasoning: A Preliminary Study
Get PDFThe purpose of this study was to test a belief-bias effect on reasoning in relation to inhibitory control functions and whether inhibition would be activated on conflict syllogisms. A total of 85 university students (78 % women, Mage = 20. 51, SD = 2. 90) participated in the study. We measured three types of inhibition and used the Brown-Peterson task and the Cued Recall task to measure proactive interference resistance, the Eriksen flanker letters and arrows task to measure distractor interference control, and the Spatial and Numerical Stroop task to measure prepotent response inhibition. We administered a syllogistic reasoning task containing no-conflict and conflict syllogisms saturated by socially relevant content. We found a typical belief-bias effect on invalid/believable conflict syllogisms, and accordingly all three types of inhibition accounted for reasoning performance only on valid/unbelievable conflict syllogisms, where belief-bias was not registered, indicating an inverse relation of bias and inhibition
Competitive trait anxiety and general self-esteem of athletes according to the sport type and gender
Get PDFTraditionally, anxiety has been interpreted as a negative emotional state characterized by nervousness, worry, fret, uncertainty and vague fear which could have an adverse effect on sports achievement. On the other hand, sport type and its specific nature and demands, may also be connected with the level of state and trait anxiety. This study aimed to investigate potential differences in the competitive trait anxiety level and general self-esteem according to gender in sports of different contact level. The sample consisted of 1024 (590 males and 434 females) young athletes. Independent variables were sport contact level (non-contact, contact and collision sports) and gender. Dependent variables were measured by the adjusted versions of Sport Competition Anxiety Test and Rosenberg Self-Esteem Scale. Basic descriptive statistics was calculated for all the groups, and the differences between them were established using χ² test and MANOVA. The results suggest significant differences in trait competitive anxiety per sport type, gender and their interaction, and no differences in the general self-esteem level. The current study reveals that not only the intensity but also the intergroup relationship of a sport contact level (non-contact, contact and collision sports) is gender determined. These findings are important in psycho-diagnostic procedure and choosing appropriate coping strategies for athletes