Study of magnetic and electrical properties of Pr0.65Ca0.25Ba0.1MnO3 manganite

The magnetic properties and magnetocaloric effect (MCE) in Pr_0.65Ca_0.25Ba_0.1MnO₃ have been investigated supplemented by electrical data. X-ray diffraction shows that the sample crystallizes in the distorted orthorhombic system with the Pnma space group. Pr_0.65Ca_0.25Ba_0.1MnO₃ undergoes paramagnetic–ferromagnetic (PM–FM) phase transition at T_C ∼ 85 K. For a magnetic field change of 5 T, the maximum value of the magnetic entropy change (−ΔS^max_M) is estimated to be 4.4 J kg⁻¹ K⁻¹ around T_C with a large relative cooling power (RCP) value of 263.5 J kg⁻¹. While the modified Arrott plots suggested that the magnetic transition belongs to the second order phase transitions, the universal curves of the rescaled magnetic entropy (ΔS_M) proved the opposite. The electrical properties of Pr_0.65Ca_0.25Ba_0.1MnO₃ have been investigated using impedance spectroscopy techniques. The dc-resistivity (σ_dc) study shows the presence of semiconductor behavior. Ac-conductivity (σ_ac) analysis shows that the conductivity is governed by a hopping process. From the analysis of the alternating regime, the exponent s variation obtained is in good agreement with Mott theory. The impedance spectrum analysis reveals the presence of a relaxation phenomenon. Based on these analyzes, the sample can be modeled by an electrical equivalent circuit.

The magnetic properties and magnetocaloric effect in Pr_0.65Ca_0.25Ba_0.1MnO₃ compound have been investigated supplemented by electrical data.     

Dietary Intake of Adult Residents in Luxembourg Taking Part in Two Cross-Sectional Studies—ORISCAV-LUX (2007–2008) and ORISCAV-LUX 2 (2016–2017)

Background: A balanced diet is an important lifestyle component and has been associated with a reduced risk of chronic diseases. Objectives: To assess dietary intake of adult residents in Luxembourg taking part in two population-based cross-sectional studies (ORISCAV-LUX, 2007–2008 and ORISCAV-LUX 2, 2016–2017). Methods: Dietary intake of the study participants (1242 in 2007/08 and 1326 in 2016/17), 25–69 years old, were evaluated using food-frequency questionnaires (134 items in 2007/2008 and 174 items in 2016/2017) according to the French ANSES-CIQUAL food composition database. Both food-group- and nutrient-based analyses were conducted. Results: Dietary patterns in ORISCAV-LUX 2, 2016–2017, were characterized by an increase in the estimated marginal means (EMM) of the intake of energy, total fat, saturated fatty acids, alcohol, and decreased EMM of total carbohydrates, magnesium, and calcium compared to 2007/08. We also observed an increased EMM of the intake of protein-rich food items and ready-to-eat foods/fast foods, together with a decreased intake of grains, dairy products, and vegetables (all p-values <0.05, linear mixed models). The intake of most micronutrients was stable or slightly increased in ORISCAV-LUX 2 vs. ORISCAV-LUX, except for the drop in magnesium and calcium, and generally met recommendations, in particular, EFSA population reference intakes (PRI), except for vitamin D. Conclusions: Though most micronutrient recommendations were met, nutrient consumption in terms of high energy, total fat, and sodium, as well as low carbohydrates, were not aligned with recommendations for balanced eating.     

The evaluate and compare the effects of the Tacrolimus and Sirolimus on the intestinal system using an intestinal cell culture model

Tacrolimus (TAC) and Sirolimus (SRL) are produced by Streptomyces sp and effective immunosuppressive drugs commonly used in organ transplantation. Therefore, strategies for minimizing the toxicity of immunosuppressant molecules are our interest. This study was conducted to evaluate the interactive effects and the possible underlying mechanism of TAC and SRL on HCT116 cells. It was found that TAC and SRL alone inhibited cell viability. Also, it induced reactive oxygen species (ROS) formation, loss of mitochondrial membrane potential (Δψm), and able to increase DNA fragmentation in a concentration-dependent manner. The use of combined SRL and TAC showed a reservation in all toxicity observed with the two immunosuppressive drugs separately. Our result demonstrated that the mechanisms of TAC and SRL at high concentration are closely connected with oxidative stress. Furthermore, SRL at low concentration plays a protective effect against TAC (IC₅₀) which induced cytotoxicity and genotoxicity. However, using the combination of the SRL/TAC at high concentrations (IC₃₀) appears as an antagonist response.     

Environmental Surveillance for Risk Assessment in the Context of a Phase 2 Clinical Trial of Type 2 Novel Oral Polio Vaccine in Panama

Environmental surveillance was recommended for risk mitigation in a novel oral polio vaccine-2 (nOPV2) clinical trial (M5-ABMG) to monitor excretion, potential circulation, and loss of attenuation of the two nOPV2 candidates. The nOPV2 candidates were developed to address the risk of poliovirus (PV) type 2 circulating vaccine-derived poliovirus (cVDPV) as part of the global eradication strategy. Between November 2018 and January 2020, an environmental surveillance study for the clinical trial was conducted in parallel to the M5-ABMG clinical trial at five locations in Panama. The collection sites were located upstream from local treatment plant inlets, to capture the excreta from trial participants and their community. Laboratory analyses of 49 environmental samples were conducted using the two-phase separation method. Novel OPV2 strains were not detected in sewage samples collected during the study period. However, six samples were positive for Sabin-like type 3 PV, two samples were positive for Sabin-like type 1 PV, and non-polio enteroviruses NPEVs were detected in 27 samples. One of the nOPV2 candidates has been granted Emergency Use Listing by the World Health Organization and initial use started in March 2021. This environmental surveillance study provided valuable risk mitigation information to support the Emergency Use Listing application.     

Phytochemical composition and the cholinesterase and xanthine oxidase inhibitory properties of seed extracts from the Washingtonia filifera palm fruit

The chemical composition and biological properties of palm Washingtonia filifera (Lindl.) H. Wendl. seeds are seldom studied. Bearing this in mind, the seeds of W. filifera fruits were analysed for their fatty acid and phenolic composition and their antioxidant activity in addition to their cholinesterase and xanthine oxidase inhibitory activities. Seed extracts were revealed as a good source of phenolics with significant antioxidant activity. The phenolic profile mainly consisted of proanthocyanidins or procyanidin dimers B1–B4 among the major compounds. The highest butyrylcholinesterase inhibitory activity was found in the ethanolic extracts of seeds, with IC₅₀ values of 13.73 ± 1.31 μg mL⁻¹. Seed alcoholic extracts also displayed interesting xanthine oxidase inhibitory activity, with IC₅₀ values ranging between 75.2 ± 17.0 μg mL⁻¹ and 95.8 ± 5.9 μg mL⁻¹. Procyanidin B1, a major component in the extracts, could be an important contributor to that activity, as it was found to possess good xanthine oxidase inhibition capacity (IC₅₀ value of 53.51 ± 6.03 μg mL⁻¹). Docking studies were also performed to predict the binding sites of procyanidins B1 and B2 within the xanthine oxidase structure. In all, W. filifera seeds appear as a promising natural source for the extraction of bioactive compounds with antioxidant and butyrylcholinesterase as well as xanthine oxidase inhibitory potential.

The chemical composition and biological properties of palm Washingtonia filifera (Lindl.) H. Wendl. seeds are seldom studied.     

Nephrotoxicity induced by chromium (VI) in adult rats and their progeny

To assess kidney damages in pregnant and lactating rats and in their suckling pups, Wistar female rats were given, through drinking water, 700 parts per million (ppm) of K(2)Cr(2)O(7) from the 14th day of pregnancy until day 14 after delivery. Toxicity was objectified by a significant increase in malondialdehyde (MDA), glutathione (GSH) and nitric oxide (NO) levels in kidney of chromium-treated mothers and their suckling pups. Moreover, lactate dehydrogenase (LDH) was increased in kidney and decreased in plasma of K(2)Cr(2)O(7)-treated rats. Activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) were increased in dams and decreased in their pups. Interestingly, these biochemical modifications were accompanied by higher plasma and lower urinary levels of creatinine, a specific indicator of glomerular function, and of urea than those of controls. Significant increase in creatinine clearance was also found in treated mothers and in their progeny. Histological studies showed an infiltration of mononuclear cells, necrosis and vascular congestion in kidney of pups and dams. Based on the present findings, K(2)Cr(2)O(7) administrated to female rats during late pregnancy and early postnatal periods provoked kidney damages in dams and their offspring.