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41.
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Vaccine adjuvants are compounds that enhance/prolong the immune response to a co-administered antigen. Saponins have been widely used as adjuvants for many years in several vaccines – especially for intracellular pathogens – including the recent and somewhat revolutionary malaria and shingles vaccines. In view of the immunoadjuvant potential of Q. brasiliensis saponins, the present study aimed to characterize the QB-80 saponin-rich fraction and a nanoadjuvant prepared with QB-80 and lipids (IMXQB-80). In addition, the performance of such adjuvants was examined in experimental inactivated vaccines against Zika virus (ZIKV). Analysis of QB-80 by DI-ESI-ToF by negative ion electrospray revealed over 29 saponins that could be assigned to known structures existing in their congener Q. saponaria, including the well-studied QS-21 and QS-7. The QB-80 saponins were a micrOTOF able to self-assembly with lipids in ISCOM-like nanoparticles with diameters of approximately 43 nm, here named IMXQB-80. Toxicity assays revealed that QB-80 saponins did present some haemolytical and cytotoxic potentials; however, these were abrogated in IMXQB-80 nanoparticles. Regarding the adjuvant activity, QB-80 and IMXQB-80 significantly enhanced serum levels of anti-Zika virus IgG and subtypes (IgG1, IgG2b, IgG2c) as well as neutralized antibodies when compared to an unadjuvanted vaccine. Furthermore, the nanoadjuvant IMXQB-80 was as effective as QB-80 in stimulating immune responses, yet requiring fourfold less saponins to induce the equivalent stimuli, and with less toxicity. These findings reveal that the saponin fraction QB-80, and particularly the IMXQB-80 nanoadjuvant, are safe and capable of potentializing immune responses when used as adjuvants in experimental ZIKV vaccines.  相似文献   
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The aim of this study was to evaluate and compare the mitogenic effect of peritoneal fluid (PF) from women with mild and severe endometriosis on the endometrial stromal cell proliferation. Increasing concentrations of PF from women with and without mild or severe endometriosis were added to primary endometrial stromal cell cultures and3H-thymidine incorporation was used to assess DNA synthesis in these cultures. PF from women with mild endometriosis induced a statistically significant dose-dependent increase in stromal cell thymidine uptake ranged from 5.8 to 14.5 fold, whereas PF from women with severe endometriosis produced an average 51% inhibition of stromal cell proliferation of compared with cells exposed to non-endometriosis PF or exposed to nutrient medium supplemented with 2.5% calf serum alone. PF samples from patients with stage I endometriosis induced a statistically dose-dependent increase in stromal cell proliferation, whereas PF from patients with stage IV endometriosis caused a significant inhibition.  相似文献   
45.
OBJECTIVE: To estimate the prevalence of tobacco use, exposure to secondhand smoke, and smoking restrictions in the home and workplace among residents of Tijuana, one of Mexico's largest cities. METHODS: This cross-sectional household survey was conducted in Tijuana, Baja California, Mexico, during 2003 and 2004. A population-based sample of 400 Tijuana adult residents responded to a tobacco survey, and 397 of the surveys were analyzed. RESULTS: About 22.9% (95% confidence interval (CI): 18.7%-27.1%) of Tijuana adults reported current smoking, and 53.9% (95% CI: 48.8%-58.9%) reported chronic exposure to secondhand smoke. Approximately 44.4% (95% CI: 37.9%-50.9%) of Tijuana adults had a nonsmoking policy in their workplace, while 65.8% (95% CI: 61.0%-70.6%) of Tijuana households were smoke-free. CONCLUSIONS: The results underline the need for increased tobacco control efforts, particularly stricter enforcement of existing passive smoking regulations, in order to expand protection from secondhand smoke from private settings to public ones and to curb the tobacco epidemic in Tijuana and elsewhere in Mexico.  相似文献   
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Scaling up breastfeeding programmes has not been highly prioritized despite overwhelming evidence that breastfeeding benefits the health of mothers and children. Lack of evidence‐based tools for scaling up may deter countries from prioritizing breastfeeding. To fill this gap, Becoming Breastfeeding Friendly (BBF) was developed to guide countries in effectively scaling up programmes to protect, promote, and support breastfeeding. BBF includes an evidence‐based toolbox that consists of a BBF Index, case studies, and a 5‐meeting process. These three interrelated components enable countries to assess their breastfeeding scaling up environment, identify gaps, propose policy recommendations, develop a scaling up plan, and track progress. The toolbox was developed based on current evidence and expert guidance from a Technical Advisory Group, which was composed of global breastfeeding and metric experts with experience in the scaling up of health and nutrition programmes in low‐, middle‐, and high‐income countries. The BBF toolbox required a step‐by‐step iterative approach to describe and systematize each component, thus an operational manual was developed. The BBF toolbox and BBF operational manual underwent intensive pretesting in two countries, Ghana and Mexico, resulting in the modification of each component plus the operational manual. Pretesting continues in six additional countries demonstrating that BBF is a robust and dynamic multi‐sectoral process that, with relatively minor adaptations, can be successfully implemented in countries across world regions.  相似文献   
48.
Infertility is a growing public health problem. Consumption of antioxidant bioactive food compounds (BFCs) that include micronutrients and non-nutrients has been highlighted as a potential strategy to protect against oxidative and inflammatory damage in the male reproductive system induced by obesity, alcohol, and toxicants and, thus, improve spermatogenesis and the fertility parameters. Paternal consumption of such dietary compounds could not only benefit the fathers but their offspring as well. Studies in the new field of paternal origins of health and disease show that paternal malnutrition can alter sperm epigenome, and this can alter fetal development and program an increased risk of metabolic diseases and breast cancer in adulthood. BFCs, such as ascorbic acid, α-tocopherol, polyunsaturated fatty acids, trace elements, carnitines, N-acetylcysteine, and coenzyme Q10, have been shown to improve male gametogenesis, modulate epigenetics of germ cells, and the epigenetic signature of the offspring, restoring offspring metabolic health induced by stressors during early life. This indicates that, from a father’s perspective, preconception is a valuable window of opportunity to start potential nutritional interventions with these BFCs to maximize sperm epigenetic integrity and promote adequate fetal growth and development, thus preventing chronic disease in adulthood.  相似文献   
49.
IntroductionOxidative stress (OS) occurs in cystic fibrosis (CF).ObjectiveThe objective of this work is to evaluate the influence of bacterial infection on biomarkers of OS (catalase [CAT], glutathione peroxidade [GPx], reduced glutathione [GSH]), markers of oxidative damage (protein carbonyls [PC], thiobarbituric acid reactive substances [TBARS]), together with the nutritional status and lung function in children with CF.MethodsCross‐sectional study including CF group (CFG, n = 55) and control group (CG, n = 31), median age: 3.89 and 4.62 years, respectively. CFG was distributed into CFG negative bacteriology (CFGB−, n = 27) or CFG positive bacteriology (CFGB+, n = 28), and CFG negative Pseudomonas aeruginosa (CFGPa−, n = 36) or CFG positive Pseudomonas aeruginosa (CFGPa+, n = 19).ResultsCompared with CG, CFG (P = .034) and CFGB+ (P = .042) had lower body mass index‐for‐age z‐score; forced expiratory volume in the first second was lower in CFGB+ and CFGPa+ (both P < .001). After adjusting for confounders and compared with CG: CFG showed higher TBARS (P ≤ .001) and PC (P = .048), and lower CAT (P = .004) and GPx (P = .003); the increase in PC levels was observed in CFGB+ (P = .011) and CFGPa+ (P = .001) but not in CFGB− (P = .510) and CFGPa− (P = .460).ConclusionsThese results indicate a systemic OS in children with CF. The presence of bacterial infection particularly Pseudomonas aeruginosa seems to be determinant to exacerbate the oxidative damage to proteins, in which PC may be a useful biomarker of OS in CF.  相似文献   
50.

Ethnopharmacological relevance

The study was aimed at evaluating medicinal and therapeutic potentials of two Lycopodiaceae species, Lycopodium clavatum (L.) and Lycopodium thyoides (Humb. & Bonpl. ex Willd), both used in South American folk medicine for central nervous system conditions. Alkaloid extracts were evaluated for chemical characterization, acetylcholinesterase and antioxidant activities.

Materials and methods

The alkaloid extracts obtained by alkaline extraction were determined for each species by GC/MS examination. The evaluation of the anticholinesterase and the antioxidant activities of the extracts were tested by determining in vitro and ex vivo models. Effects on acetylcholinesterase (AChE) were tested in vitro using rat brain homogenates and ex vivo after a single administration (25, 10 and 1 mg/kg i.p.) of the alkaloid extracts in mice. The in vitro antioxidant effects were tested for the 2-deoxyribose degradation, nitric oxide (NO) interaction, 2,2-diphenyl-1-picryl hydrazyl (DPPH) radical scavenging activity and total reactive antioxidant potential (TRAP). After an acute administration (25 and 10 mg/kg i.p.) of the extracts in middle-aged (12 months) mice, the antioxidant effects were estimated through the thiobarbituric acid reactive substances test (TBARS), and the antioxidant enzymes activities for catalase (CAT) and superoxide dismutase (SOD) were measured.

Results

AChE activity was inhibited in vitro by the alkaloid-enriched extracts of both Lycopodium species in a dose and time-dependent manner in rat cortex, striatum and hippocampus. A significant inhibition was also observed in areas of the brain after acute administration of extracts, as well as decreased lipid peroxidation and increased CAT activity in the cortex, hippocampus and cerebellum. A moderate antioxidant activity was observed in vitro for the extracts. Chemically, the main alkaloids found for the two species were lycopodine and acetyldihidrolycopodine.

Conclusion

This study showed that the biological properties of the folk medicinal plants Lycopodium clavatum and Lycopodium thyoides include AChE inhibitory activity and antioxidant effects, two possible mechanisms of action in Alzheimer's related processes.  相似文献   
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