Evaluation of the antimicrobial, antioxidant and physicochemical properties of Poly(Vinyl chloride) films containing quercetin and silver nanoparticles

This work provides details regarding the physicochemical, antimicrobial and antioxidant properties of poly(vinyl chloride) (PVC)-based films containing 0.4% quercetin and silver nanoparticles (AgNPs) at various concentrations levels. The incorporation of quercetin and AgNPs into the PVC matrix considerably affected the thermal, mechanical and optical properties of the films. Results obtained from the tensile stresgth test, demonstrated an improvement in the mechanical strength of the films after the incorporation of both quercetin and AgNPs. Moreover, an increase in AgNPs concentration increased the rigidity, as compared to control PVC film. Antimicrobial activity against food pathogens (Escherichia coli, Salmonella Typhimurium and Listeria monocytogenes) was evaluated by an antimicrobial barrier test. Results showed that the PVC-based films with quercetin and AgNPs proved to be highly effective to inhibiting bacterial growth. Therefore, these results indicate promising evidence to possibly aid in the prevention of microbial dissemination in foods. Additionally, films incorporated with quercetin and AgNPs expressed an antioxidant capacity when evaluated via the DPPH method. Among all of the films evaluated, the PVC-based films containing 0.4% quercetin and 1% AgNPs were flexible, exhibiting excellent UV-light barrier properties and for use with fatty foods, with the intent of reducing lipid oxidation and preventing food pathogen dissemination.Fil: Braga, Lilian R.. Universidade do Brasília; BrasilFil: Perez, Leonardo Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; ArgentinaFil: Soazo, Marina del Valle. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; ArgentinaFil: Machado, Fabricio. Universidade do Brasília; Brasi

Altered Umbilical Cord Blood Nutrient Levels, Placental Cell Turnover and Transporter Expression in Human Term Pregnancies Conceived by Intracytoplasmic Sperm Injection (ICSI)

Assisted reproductive technologies (ART) may increase risk for abnormal placental development, preterm delivery and low birthweight. We investigated placental morphology, transporter expression and paired maternal/umbilical fasting blood nutrient levels in human term pregnancies conceived naturally (n = 10) or by intracytoplasmic sperm injection (ICSI; n = 11). Maternal and umbilical vein blood from singleton term (>37 weeks) C-section pregnancies were assessed for levels of free amino acids, glucose, free fatty acids (FFA), cholesterol, high density lipoprotein (HDL), low density lipoprotein (LDL), very low-density lipoprotein (VLDL) and triglycerides. We quantified placental expression of GLUT1 (glucose), SNAT2 (amino acids), P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) (drug) transporters, and placental morphology and pathology. Following ICSI, placental SNAT2 protein expression was downregulated and umbilical cord blood levels of citrulline were increased, while FFA levels were decreased at term (p < 0.05). Placental proliferation and apoptotic rates were increased in ICSI placentae (p < 0.05). No changes in maternal blood nutrient levels, placental GLUT1, P-gp and BCRP expression, or placental histopathology were observed. In term pregnancies, ICSI impairs placental SNAT2 transporter expression and cell turnover, and alters umbilical vein levels of specific nutrients without changing placental morphology. These may represent mechanisms through which ICSI impacts pregnancy outcomes and programs disease risk trajectories in offspring across the life course

Naturally acquired antibodies to Plasmodium vivax blood-stage vaccine candidates (PvMSP-1(19) and PvMSP-3 alpha(359-798)) and their relationship with hematological features in malaria patients from the Brazilian Amazon

An important step when designing a vaccine is identifying the antigens that function as targets of naturally acquired antibodies. We investigated specific antibody responses against two Plasmodium vivax vaccine candidates, PvMSP-1(19) and PvMSP-3 alpha(359-798). Moreover, we assessed the relationship between these antibodies and morbidity parameters. PvMSP-1(19) was the most immunogenic antigen and the frequency of responders to this protein tended to increase in P. vivax patients with higher parasitemia. For both antigens, IgG antibody responses tended to be lower in patients who had experienced their first bout of malaria. Furthermore, anemic patients presented higher IgG antibody responses to PvMSP-3 alpha(359-798). Since the humoral response involves a number of antibodies acting simultaneously on different targets, we performed a Principal Component Analysis (PCA). Anemic patients had, on average, higher first principal component scores (IgG1/IgG2/IgG3/IgG4 anti-MSP3 alpha), which were negatively correlated with hemoglobin levels. Since antibodies against PfMSP-3 have been strongly associated with clinical protection, we cannot exclude the possibility of a dual role of PvMSP-3 specific antibodies in both immunity and pathogenesis of vivax malaria. Our results confirm the high immunogenicity of the conserved C terminus of PvMSP-1 and points to the considerable immunogenicity of polymorphic PvMSP-3 alpha(359-798) during natural infection. (C) 2012 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.CNPqCNPqFundacao de Amparo a Pesquisa do Estado de Minas Gerais (FAPEMIG)Fundacao de Amparo a Pesquisa do Estado de Minas Gerais/FAPEMIG [CBB PPM-0003-09 e CBB - PPM-00177-11]Conselho Nacional de Pesquisa (CNPq, Brazil)Conselho Nacional de Pesquisa (CNPq/Brazil) [471156/2010-8]Pronex Malaria, DECIT/MS [555646/2009-2]Pronex Malaria, DECIT/M