4 research outputs found
FENOLES DEL POLEN DE STENOCACTUS, ECHINOCEREUSY MAMMILLARIA(CACTACEAE)
A variable number of phenolics have beendetected in pollen of the following speciesof Cactaceae: Stenocactus multicostatussubsp. zacatecasensis, Echinocereusenneacanthus, Echinocereus pectinatus,Echinocereus triglochidiatus var.coccineus and Mammillaria heyderi sensulato. The phenolics were characterized by means of chromatographic (HPLC) andspectrometric (UV) properties. The mostabundant flavonols were 3-O-glycosidederivatives of kaempferol and 3-Oglycoside derivatives of quercetin. 3-Oglycoside derivatives of herbacetin werefound in lower abundance. Each species hada particular pollen phenolic profile.Intrapopulation variability in phenolicprofiles was detected in all cases. Thephenolic composition of these species isreported for the first time.Un número variable de compuestosfenólicos ha sido detectado en el polen deStenocactus multicostatus subsp.zacatecasensis (Britton et Rose) U. Guzmánet Vázquez-Benítez, comb. et stat. nov.,Echinocereus enneacanthus Engelm.,Echinocereus pectinatus (Scheidw.)Engelm., Echinocereus triglochidiatus var.coccineus (Engelm.) U. Guzmán, comb. etstat. nov. y Mammillaria heyderi sensulato, todas de la familia Cactaceae. Loscompuestos fenólicos fueron caracterizados por sus propiedades cromatográficas (HPLC) y espectrométricas (UV).Los fenoles encontrados fueron derivadosde ácidos fenólicos y flavonoides. Estosúltimos estuvieron representados porflavonoles, de éstos los más abundantesfueron los 3-O-glicósidos derivados decanferol y quercetina. En menor abundancia se encontraron derivados 3-O-glicósidos deherbacetina. Variabilidad intrapoblacionalen la composición fenólica del polen fueregistrada en todos los casos. Cada unode los taxa presentó un perfil fenólicoparticular. La composición de fenoles delpolen de estas especies es presentada porprimera vez
Antioxidant activity of polyphenolic extract of monofloral honeybee-collected pollen from mesquite (Prosopis juliflora, Leguminosae)
The antioxidant capacity related to the phenolic composition of monospecific honeybee-collected pollen extract from the mesquite tree (Prosopis juliflora) from Durango, Mexico, was evaluated in an in vitro-biological system (as inhibitor of lipid peroxidation on mouse hepatic microsomal preparations) and in an in vivo system (on homogenized liver of bromobenzene-intoxicated mice) by quantification of thiobarbituric acid-reactive substances (TBARS). The comparison of results obtained from these two different systems was also made. The results obtained suggest that pollen of P. juliflora is an important source of flavonoids, which can be considered as natural antioxidants. Mesquite pollen extracts showed antioxidant activity related to the flavonol concentration in both the in vitro-biological system and the in vivo system with a lower activity in the latter of these systems. Under in vivo conditions and in those in which a state of oxidation in not induced, a high concentration of flavonols in the extract of mesquite pollen can have a pro-oxidant effect.http://www.sciencedirect.com/science/article/B6WJH-4M7VB2N-2/1/eb76172de84abb91a436acbdfa19384
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Effects of pre-operative isolation on postoperative pulmonary complications after elective surgery: an international prospective cohort study an international prospective cohort study
We aimed to determine the impact of pre-operative isolation on postoperative pulmonary complications after elective surgery during the global SARS-CoV-2 pandemic. We performed an international prospective cohort study including patients undergoing elective surgery in October 2020. Isolation was defined as the period before surgery during which patients did not leave their house or receive visitors from outside their household. The primary outcome was postoperative pulmonary complications, adjusted in multivariable models for measured confounders. Pre-defined sub-group analyses were performed for the primary outcome. A total of 96,454 patients from 114 countries were included and overall, 26,948 (27.9%) patients isolated before surgery. Postoperative pulmonary complications were recorded in 1947 (2.0%) patients of which 227 (11.7%) were associated with SARS-CoV-2 infection. Patients who isolated pre-operatively were older, had more respiratory comorbidities and were more commonly from areas of high SARS-CoV-2 incidence and high-income countries. Although the overall rates of postoperative pulmonary complications were similar in those that isolated and those that did not (2.1% vs 2.0%, respectively), isolation was associated with higher rates of postoperative pulmonary complications after adjustment (adjusted OR 1.20, 95%CI 1.05–1.36, p = 0.005). Sensitivity analyses revealed no further differences when patients were categorised by: pre-operative testing; use of COVID-19-free pathways; or community SARS-CoV-2 prevalence. The rate of postoperative pulmonary complications increased with periods of isolation longer than 3 days, with an OR (95%CI) at 4–7 days or ≥ 8 days of 1.25 (1.04–1.48), p = 0.015 and 1.31 (1.11–1.55), p = 0.001, respectively. Isolation before elective surgery might be associated with a small but clinically important increased risk of postoperative pulmonary complications. Longer periods of isolation showed no reduction in the risk of postoperative pulmonary complications. These findings have significant implications for global provision of elective surgical care. We aimed to determine the impact of pre-operative isolation on postoperative pulmonary complications after elective surgery during the global SARS-CoV-2 pandemic. We performed an international prospective cohort study including patients undergoing elective surgery in October 2020. Isolation was defined as the period before surgery during which patients did not leave their house or receive visitors from outside their household. The primary outcome was postoperative pulmonary complications, adjusted in multivariable models for measured confounders. Pre-defined sub-group analyses were performed for the primary outcome. A total of 96,454 patients from 114 countries were included and overall, 26,948 (27.9%) patients isolated before surgery. Postoperative pulmonary complications were recorded in 1947 (2.0%) patients of which 227 (11.7%) were associated with SARS-CoV-2 infection. Patients who isolated pre-operatively were older, had more respiratory comorbidities and were more commonly from areas of high SARS-CoV-2 incidence and high-income countries. Although the overall rates of postoperative pulmonary complications were similar in those that isolated and those that did not (2.1% vs 2.0%, respectively), isolation was associated with higher rates of postoperative pulmonary complications after adjustment (adjusted OR 1.20, 95%CI 1.05–1.36, p = 0.005). Sensitivity analyses revealed no further differences when patients were categorised by: pre-operative testing; use of COVID-19-free pathways; or community SARS-CoV-2 prevalence. The rate of postoperative pulmonary complications increased with periods of isolation longer than 3 days, with an OR (95%CI) at 4–7 days or ≥ 8 days of 1.25 (1.04–1.48), p = 0.015 and 1.31 (1.11–1.55), p = 0.001, respectively. Isolation before elective surgery might be associated with a small but clinically important increased risk of postoperative pulmonary complications. Longer periods of isolation showed no reduction in the risk of postoperative pulmonary complications. These findings have significant implications for global provision of elective surgical care