23 research outputs found
Chemical composition and antibacterial and antioxidant activity of a citrus essential oil and its fractions
ABSTRACT
Essential oils (EOs) from Citrus are the main by-product of Citrus-processing industries. In addition to food/beverage and cosmetic applications, citrus EOs could also potentially be used as an alternative to antibiotics in food-producing animals. A commercial citrus EO—Brazilian Orange Terpenes (BOT)—was fractionated by vacuum fractional distillation to separate BOT into various fractions: F1, F2, F3, and F4. Next, the chemical composition and biological activities of BOT and its fractions were characterized. Results showed the three first fractions had a high relative amount of limonene (≥10.86), even higher than the whole BOT. Conversely, F4 presented a larger relative amount of BOT’s minor compounds (carvone, cis-carveol, trans-carveol, cis-p-Mentha-2,8-dien-1-ol, and trans-p-Mentha-2,8-dien-1-ol) and a very low relative amount of limonene (0.08–0.13). Antibacterial activity results showed F4 was the only fraction exhibiting this activity, which was selective and higher activity on a pathogenic bacterium (E. coli) than on a beneficial bacterium (Lactobacillus sp.). However, F4 activity was lower than BOT. Similarly, F4 displayed the highest antioxidant activity among fractions (equivalent to BOT). These results indicated that probably those minor compounds that detected in F4 would be more involved in conferring the biological activities for this fraction and consequently for the whole BOT, instead of the major compound, limonene, playing this role exclusively
Coffee consumption increases the antioxidant capacity of plasma and has no effect on the lipid profile or vascular function in healthy adults in a randomized controlled trial
ABSTRACT: Coffee, a source of antioxidants, has controversial effects on cardiovascular health. Objective: We evaluated the bioavailability of chlorogenic acids (CGAs) in 2 coffees and the effects of their consumption on the plasma antioxidant capacity (AC), the serum lipid profile, and the vascular function in healthy adults. Methods: Thirty-eight men and 37 women with a mean 6 SD age of 38.5 6 9 y and body mass index of 24.1 6 2.6 kg/m2 were randomly assigned to 3 groups: a control group that did not consume coffee or a placebo and 2 groups that consumed 400 mL coffee/d for 8 wk containing a medium (MCCGA; 420 mg) or high (HCCGA; 780 mg) CGA content. Both were low in diterpenes (0.83 mg/d) and caffeine (193 mg/d). Plasma caffeic and ferulic acid concentrations were measured by GC, and the plasma AC was evaluated with use of the ferric-reducing antioxidant power method. The serum lipid profile, nitric oxide (NO) plasma metabolites, vascular endothelial function (flow-mediated dilation; FMD), and blood pressure (BP) were evaluated.Results: After coffee consumption (1 h and 8 wk), caffeic and ferulic acid concentrations increased in the coffee-drinking
groups, although the values of the 2 groups were significantly different (P < 0.001); caffeic and ferulic acid concentrations were undetectable in the control group. At 1 h after consumption, the plasma AC in the control group was significantly lower than the baseline value (22%) and significantly increased in the MCCGA (6%) and HCCGA (5%) groups (P < 0.05). After 8 wk, no significant differences in the lipid, FMD, BP, or NO plasma metabolite values were observed between the groups. Conclusions: Both coffees, which contained CGAs and were low in diterpenes and caffeine, provided bioavailable CGAs and had a positive acute effect on the plasma AC in healthy adults and no effect on blood lipids or vascular function. The group that did not drink coffee showed no improvement in serum lipid profile, FMD, BP, or NO plasma metabolites. This trial was registered at registroclinico.sld.cu as RPCEC00000168
Desarrollo de estrategias para el manejo sostenible de la Altillanura Colombiana
Los Llanos Orientales de Colombia cubren cerca de 26 millones de hectáreas de las cuales un 53% (14 millones) pertenecen a la Orinoquia bien drenada (terrazas aluviales Altillanura plana y Altillanura disectada) Sin embargo el gran potencial agropecuario lo constituyen cerca de 46
millones de hectáreas constituidas por las terrazas y Altillanura plana actualmente subutilizadas
en una ganadería extensiva con pastos de baja calidad nutricional Los suelos de estas sabanas de
la Orinoquia se caracterizan por su alta acidez baja fertilidad química baja actividad biológica y
débil estructura física que los hace fuertemente susceptibles a erosión y a compactación Aun así
estos ecosistemas presentan ventajas comparativas con relación a otras zonas de producción agropecuaria del País por su abundante y buena distribución de lluvias y topografía relativamente plana que facilita la utilización racional de la mecanización como practica agrícola constructora de suelos y no degradativa
The gut microbiota of Colombians differs from that of Americans, Europeans and Asians
ABSTRACT: The composition of the gut microbiota has recently been associated with health and disease, particularly with obesity. Some studies suggested a higher proportion of Firmicutes and a lower proportion of Bacteroidetes in obese compared to lean people; others found discordant patterns. Most studies, however, focused on Americans or Europeans, giving a limited picture of the gut microbiome. To determine the generality of previous observations and expand our knowledge of the human gut microbiota, it is important to replicate studies in overlooked populations. Thus, we describe here, for the first time, the gut microbiota of Colombian adults via the pyrosequencing of the 16S ribosomal DNA (rDNA), comparing it with results obtained in Americans, Europeans, Japanese and South Koreans, and testing the generality of previous observations concerning changes in Firmicutes and Bacteroidetes with increasing body mass index (BMI). Results: We found that the composition of the gut microbiota of Colombians was significantly different from that of Americans, Europeans and Asians. The geographic origin of the population explained more variance in the composition of this bacterial community than BMI or gender. Concerning changes in Firmicutes and Bacteroidetes with obesity, in Colombians we found a tendency in Firmicutes to diminish with increasing BMI, whereas no change was observed in Bacteroidetes. A similar result was found in Americans. A more detailed inspection of the Colombian dataset revealed that five fiber-degrading bacteria, including Akkermansia, Dialister, Oscillospira, Ruminococcaceae and Clostridiales, became less abundant in obese subjects. Conclusion: We contributed data from unstudied Colombians that showed that the geographic origin of the studied population had a greater impact on the composition of the gut microbiota than BMI or gender. Any strategy aiming to modulate or control obesity via manipulation of this bacterial community should consider this effect
Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2
The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality
Método heurístico en la resolución de problemas matemáticos
La educación hoy en día busca cambiar los modelos tradicionales, pues estos métodos han presentado muchas falencias a través del tiempo, por esta razón se han introducido nuevas teorías e investigaciones en el campo educativo, donde el docente debe ser un investigador permanente en su propia aula de clase porque esto le permite cualificar su labor. Este trabajo parte de la necesidad de cambiar algunas estrategias didácticas en la enseñanza del área de matemáticas, ya que según los resultados de las pruebas SABER no se han alcanzado los desempeños esperados en los estudiantes del grado quinto de básica primaria, además las prácticas del proyecto pedagógico realizadas a través de la carrera han permitido observar que los alumnos en los diferentes grados de la básica primaria presentan dificultades en el proceso resolutivo de los problemas matemáticos, ya que aunque saben realizar las cuatro operaciones matemáticas no saben identificar que operación deben efectuar de acuerdo al enunciado del problema. También es importante destacar que en las planeaciones llevadas a cabo durante las prácticas pedagógicas era necesario apoyarse en los lineamientos curriculares y estos plantean los cuatro pasos del método heurístico de George Polya (comprender el problema, elaborar un plan, ejecutar el plan y visión retrospectiva) En este orden de ideas se ha considerado importante utilizar el método heurístico como un proceso analítico y reflexivo que permite mejorar la capacidad resolutiva de los problemas matemáticos, lo que llevó a plantear el siguiente interrogante ¿Utilizando el método heurístico de George Polya mejora la capacidad de resolución de oblemas matemáticos los (las) estudiantes de quinto (5) grado de básica primaria de la institución educativa Camilo Torres?
Relación entre Estrategias Competitivas y Tipos de Aprendizaje Organizativo en Empresas Colombianas
Cambios en la presión arterial en un grupo de voluntarios normotensos después del consumo de diferentes dosis de café filtrado Changes in blood pressure in a group of normotense volunteers after consumption or different doses of filtered coffee
No es clara la asociación entre el consumo de café y los cambios en los niveles de presión arterial; si bien algunos estudios muestran una correlación positiva, otros no logran confirmarla. El objetivo de este estudio fue determinar el cambio en los niveles de presión arterial en un grupo de voluntarios normotensos sometidos al consumo de diferentes dosis de café filtrado. Se trata de un estudio prospectivo, clínico controlado, en el cual se conformaron cuatro grupos y se sometieron por un período de seis semanas al consumo de diferentes cantidades de café filtrado: el grupo uno no consumió café, el grupo dos consumió 200 mL, el tres 400 mL y el cuatro 600 mL. Antes y al final de la intervención, en cada sujeto se midieron los niveles de presión arterial; en el grupo control se midió la concentración de cafeína antes, durante y al final de la intervención. Los resultados mostraron grupos comparables por género, edad e índice de masa corporal, sin diferencias significativas en las condiciones basales. Después de la intervención, la presión arterial sistólica y diastólica no mostró diferencia intragrupos, excepto en el grupo cuatro en el cual disminuyó significativamente (p=0,006) la presión arterial diastólica. Entre grupos los cambios en los niveles de presión sistólica y diastólica no fueron significativos (p=0,510 y 0,430 respectivamente). En conclusión, el consumo de diferentes dosis de café filtrado no ocasionó en sujetos normotensos cambios significativos en los niveles de presión arterial; el grupo que se abstuvo de tomar café no mostró disminución significativa de la presión arterial.<br>The association between coffee consumption and changes in blood pressure values is not clear yet. Although some studies show a positive correlation, others fail to confirm it. The aim of this study was to determine changes in blood pressure values in a group of normotense volunteers submitted to consumption of different doses of filtered coffee. This is a prospective clinical controlled study in which four groups were conformed and were submitted during a period of six weeks to consumption of different doses of filtered coffee: group one did not have coffee, group two consumed 200 mL, group three 400 mL and group four 600 mL. Blood pressure values were measured before and at the end of the intervention in each subject; in the control group coffeine concentration was measured before, during and at the end of the intervention. The results showed comparable groups by gender, age and body mass index, without significant differences in basal conditions. After the intervention, systolic and diastolic blood pressure did not show any difference between the groups, with the exception of group four in which diastolic blood pressure diminished significantly (p=0.006). Between the groups, the changes in systolic and diastolic blood pressure values were not significant (p=0.510 and 0.430 respectively). In conclusion, consumption of different doses of filtered coffee did not cause significant changes in blood pressure values; the group that did not have coffee did not show significant lowering of blood pressure values
Evaluación de factores genéticos y ambientales en los componentes del síndrome metabólico en una muestra de jóvenes
Prevalencia de anemia ferropénica en escolares y adolescentes, Medellín, Colombia, 1999 Prevalence of iron-deficiency anemia in schoolchildren and adolescents, Medellín, Colombia, 1999
OBJETIVO: Determinar la prevalencia de anemia ferropénica y describir el consumo de hierro en la dieta de escolares y adolescentes matriculados en colegios oficiales y privados de la zona urbana de la ciudad de Medellín, Colombia, en el año escolar 1999­2000, así como explorar la asociación entre grupo de edad, sexo, clase socioeconómica y parasitismo intestinal por un lado, y anémica ferropénica y deficiencia de hierro por el otro. MÉTODOS: Se realizó un estudio de corte transversal en 960 estudiantes de 6 a 18 años de edad que fueron elegidos por muestreo aleatorio simple tras un muestreo polietápico estratificado y por conglomerados de colegios oficiales y privados en comunas de la zona de Medellín. Se evaluaron el contenido corporal de hierro mediante determinaciones de ferritina, hemoglobina, volumen corpuscular medio y amplitud de la distribución eritrocitaria; la presencia de parásitos intestinales mediante análisis coprológico; el estado nutricional por medio de mediciones antropométricas; y el consumo de hierro y vitamina C mediante un cuestionario semicuantitativo de ingesta alimentaria. Para definir los casos de anemia ferropénica y de deficiencia de hierro se usaron las definiciones estándar de la Organización Mundial de la Salud basadas en los valores de ferritina y hemoglobina. También se examinó la asociación entre grupo de edad, sexo, clase socioeconómica y presencia de parásitos intestinales por un lado y la presencia de anemia por el otro mediante pruebas no paramétricas con un nivel de significación de 0,05. RESULTADOS: La prevalencia de deficiencia de hierro fue de 4,9% y la de anemia ferropénica, de 0,6%. Se encontró una mayor prevalencia de ambas en mujeres adolescentes (P < 0,05) que en el resto de la muestra estudiada. No se demostró ninguna asociación significativa entre la presencia de parásitos intestinales y la de anemia. El consumo promedio de hierro diario fue de 5,5 ±2,3 mg (desviación estándar [DE]) (32% ±15% [DE] de la ingesta dietética recomendada [RDA] para el grupo de edad estudiado); el aporte promedio de hierro hemático en la dieta fue de 0,7 ±0,7 mg [DE]. No se encontraron diferencias significativas en la cantidad y el tipo de hierro consumido entre los niños con y sin anemia. El parámetro antropométrico que mostró la mayor asociación con la presencia de anemia fue la relación entra la estatura y la edad. CONCLUSIONES: Las prevalencias de anemia ferropénica y deficiencia de hierro encontradas en la población estudiada fueron bajas, de acuerdo con los parámetros de hemoglobina y ferritina definidos por la Organización Mundial de la Salud como normales para estos grupos poblacionales. La baja prevalencia de parásitos hematófagos, un consumo adecuado de vitamina C y los finos mecanismos de regulación del metabolismo del hierro pueden haber contribuido a estos resultados. Se debe velar por un contenido adecuado de hierro en la dieta de las adolescentes y poner en marcha campañas educativas que contribuyan a prevenir la deficiencia de hierro en este grupo poblacional.<br>OBJECTIVE: This research had two objectives: (1) to determine the prevalence of iron-deficiency anemia and describe iron consumption in the diet of schoolchildren and adolescents enrolled in public and private schools of the urban area of the city of Medellín, Colombia, in the 1999­2000 school year and (2) to explore the associations that age group, sex, socioeconomic class, and intestinal parasitism show with iron-deficiency anemia and iron deficiency. METHODS: A cross-sectional study was carried out among 960 students from 6 to 18 years old who were selected by simple random sampling after stratified multistage sampling and clustering in public and private schools in districts of Medellín. Body iron content was evaluated by determining ferritin and hemoglobin levels, average corpuscular volume, and amplitude of the erythrocyte distribution; the presence of intestinal parasites was evaluated through stool analysis; nutritional status was evaluated by means of anthropometric measurements; and consumption of iron and vitamin C was evaluated using a semiquantitative questionnaire on food intake. In order to define the cases of iron-deficiency anemia and of iron deficiency we used the standard definitions of the World Health Organization, based on ferritin and hemoglobin values. We used nonparametric tests, with a significance level of 0.05, to examine the associations between age group, sex, socioeconomic class, and the presence of intestinal parasites on the one hand and the presence of anemia on the other hand. RESULTS: The prevalence of iron deficiency was 4.9%, and the prevalence of iron-deficiency anemia was 0.6%. The prevalence of both was higher among adolescent women (P < 0.05) than in the rest of the sample studied. No significant association was found between the presence of intestinal parasites and the presence of anemia. The average daily consumption of iron (± standard deviation) was 5.5 mg (± 2.3 mg) (32% ± 15% of the recommended dietary intake for the studied age group); the average contribution of serum iron in the diet was 0.7 mg (± 0.7 mg). Comparing the children who did and who did not have anemia, there were no significant differences in iron consumption and the type of iron consumed. The anthropometric parameter that showed the greatest association with the presence of anemia was height for age. CONCLUSIONS: The prevalences of iron deficiency and of iron-deficiency anemia found in the population studied were low, according to the parameters for hemoglobin and ferritin as defined by the World Health Organization as being normal for these population groups. The low prevalence of blood-sucking parasites, adequate consumption of vitamin C, and the refined mechanisms with which the body regulates iron homeostasis may have contributed to these results. Adequate iron content in the diet of adolescents should be maintained, and education campaigns should be implemented to help prevent iron deficiency in this population group