61 research outputs found
Evidence of suppression of onchocerciasis transmission in the Venezuelan Amazonian focus.
BACKGROUND: The World Health Organization (WHO) has set goals for onchocerciasis elimination in Latin America by 2015. Most of the six previously endemic countries are attaining this goal by implementing twice a year (and in some foci, quarterly) mass ivermectin (Mectizan®) distribution. Elimination of transmission has been verified in Colombia, Ecuador and Mexico. Challenges remain in the Amazonian focus straddling Venezuela and Brazil, where the disease affects the hard-to-reach Yanomami indigenous population. We provide evidence of suppression of Onchocerca volvulus transmission by Simulium guianense s.l. in 16 previously hyperendemic Yanomami communities in southern Venezuela after 15 years of 6-monthly and 5 years of 3-monthly mass ivermectin treatment. METHODS: Baseline and monitoring and evaluation parasitological, ophthalmological, entomological and serological surveys were conducted in selected sentinel and extra-sentinel communities of the focus throughout the implementation of the programme. RESULTS: From 2010 to 2012–2015, clinico-parasitological surveys indicate a substantial decrease in skin microfilarial prevalence and intensity of infection; accompanied by no evidence (or very low prevalence and intensity) of ocular microfilariae in the examined population. Of a total of 51,341 S. guianense flies tested by PCR none had L3 infection (heads only). Prevalence of infective flies and seasonal transmission potentials in 2012–2013 were, respectively, under 1 % and 20 L3/person/transmission season. Serology in children aged 1–10 years demonstrated that although 26 out of 396 (7 %) individuals still had Ov-16 antibodies, only 4/218 (2 %) seropositives were aged 1–5 years. CONCLUSIONS: We report evidence of recent transmission and morbidity suppression in some communities of the focus representing 75 % of the Yanomami population and 70 % of all known communities. We conclude that onchocerciasis transmission could be feasibly interrupted in the Venezuelan Amazonian focus. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13071-016-1313-z) contains supplementary material, which is available to authorized users
Effect of oat β-glucan on glycemic index and glycemic load of a nutritional supplement sweetened with sucralose in healthy adults: A randomized clinical trial
Indexación: Scopus; RedalycLas propiedades hipoglicemiantes del β-glucano de avena
son de interés para la industria alimentaria y el área clínica,
por sus potenciales beneficios sobre la salud al disminuir la
respuesta glicémica, el nivel sérico de lipoproteínas de baja
densidad y el índice glicémico de los alimentos. Existen suplementos
nutricionales específicos para diabéticos edulcorados
con sucralosa cuyo índice glicémico y carga glicémica
aún no han sido establecidos. El efecto del β-glucano de
avena sobre el índice glicémico y carga glicémica de un suplemento
nutricional edulcorado con sucralosa, fue determinado
en 13 adultos sanos (6 hombres y 7 mujeres), quienes
consumieron aleatoriamente 4 alimentos en días distintos, de
50 g de carbohidratos cada uno: suplemento nutricional para
diabéticos (FN), suplemento nutricional con β-glucano (FN-
β), y como productos de referencia: solución glucosada (SG)
y pan blanco (PB). Se midió glicemia en ayunas y post- prandial
a los tiempos 15, 30, 45, 60, 90 y 120 min. El área bajo
la curva de glicemia resultó más baja para ambas fórmulas
(FN) 12697±993, (FN-β) 11584 ±1171, que para los productos
de referencia:(SG) 13900±1245, y (PB) 13267 ± 1557.
Los valores de índice glicémico (FN) 67,02 ± 5,69, así como
la carga glicémica resultaron intermedios y más bajos para el
suplemento con β-glucano incorporado (FN –β) 59,8 ± 6,2;
sin diferencias en la concentración de insulina, sugiriendo
que la adición del β-glucano derivado de la avena reduce la
velocidad de absorción intestinal de la glucosa, efecto que
podría estudiarse en diabéticos.The hypoglycemic properties of oat β-glucan is of interest
for the food industry and clinical area, for potencial health
benefits by reducing glycemic response, serum low-density
lipoprotein cholesterol, and glycemic index of meals. There
are specific nutritional supplements for diabetics sweetened
with sucralose whose glycemic index and glycemic load has
not been established. Effect of oat β-glucan on glycemic
index and glycemic load of a nutritional supplement sweetened
with sucralose in healthy adults was determined in 13
healthy subjects (6 men and 7 women) old that consumed
randomly 4 meals of 50 g of carbohydrates each in different
days: a nutritional supplement for diabetics (FN), the nutritional
supplement with β-glucan incorporated (FN-β) and two
reference food, glucose solution (SG) and white bread (PB).
Fasting and postprandial glycemia was measured at times
15, 30, 45, 60, 90 and 120 min. The area under the glycemia
curve was lower for both formulas (FN) 12697±993, (FN-β)
11584 ±1171 than for reference products (SG) 13900±1245,
y (PB) 13267 ± 1557. The values of glycemic index (GI) (FN)
67, 02 ± 5,69 and glycemic load were intermediate and more
lower for the supplement with β-glucan incorporated (FN –β)
59, 8 ± 6,2, with no difference of insulin concentration . Suggesting
that the addition of oat-derived β-glucan reduces the
rate of intestinal absorption of glucose. This effect should be
studied in diabetic.http://www.redalyc.org/articulo.oa?id=5594990800
Comparison of fiber effect on glycemic index and glycemic load in differents types of bread
Indexación: Scopus; Redalyc.Existen diversos alimentos que contienen como nutriente
principal hidratos de carbono, destacando entre ellos el pan
por su masivo consumo a nivel mundial. Numerosos estudios
se han llevado a cabo con el fin de reducir su índice glicémico,
sin embargo, aún existe controversia sobre la acción de
la fibra dietética en la disminución del IG en este alimento.
Este estudio determinó el efecto de la fibra dietética sobre el
índice glicémico y carga glicémica en dos tipos de panes comerciales
en 23 individuos sanos quienes consumieron aleatoriamente
3 diferentes productos, de 50 g de carbohidratos
cada uno, durante 6 días: pan blanco (PH), pan integral (PF),
y solución glucosada como producto de referencia (SG). Se
midió glicemia en ayunas y post-prandial a los tiempos 15,
30, 45, 60, 90 y 120 min. La insulina fue medida en el minuto
0 y 120 min. El área bajo la curva de glicemia resultó
más baja para ambos tipos de pan PH 13589 ±1557, PF
12005 ±1254 que para el producto de referencia SG 14089
±1245. Los valores del índice glicémico PH 68,55 ±1,2 y PF
62,10 ±1,3 y carga glicémica PH 16,45 ±1,4 resultaron más
bajos para el pan con mayor aporte de fibra 9,93 ± 1,1, sin
diferencias en la concentración de insulina, sugiriendo que
la cantidad de carbohidratos y tipo de fibra contenidos en el
pan integral, pueden considerarse factores intrínsecos en su
composición nutricional, capaces de afectar la respuesta glicémica
post- ingesta de estos productos en individuos sanos.There are several foods that contain carbohydrates as the
main nutrient, being one of the most important the bread for
its massive worldwide consumption. Numerous studies have
been done in order to reduce its glycemic index, however
there is still controversy about the action of dietary fiber in the
decrease of GI in this product. In this study, it was determined
the effect of dietetic fiber on glycemic index and glycemic load
in two types of commercial breads in 23 healthy individuals
who randomly consumed 3 different products during 6 days
of 50g of carbohydrates each: white bread (PH), whole wheat
bread (PE) and glucose solution as reference product (SG).
Fasting and postprandial glycemia was measured at times
15, 30, 45, 60, 90 and 120 minutes. Insuline was measured
at 0 min and 120 min. The area under de glycemia curve
was lower for both bread types PH 13589 ±1557, PF 12005
±1254 than for the reference product SG 14089 ±1245. The
values of the glycemic index PH 68,55 ±1,2 and PF 62,01
±1,3 and glycemic load PH 16.45 ±1,4 were lower for bread
with more amount fiber 9,93 ± 1,1, with no difference in insulin
concentration, suggesting that the amount of carbohydrates
and fiber type contained in whole wheat bread can
be considered intrinsic factors in bread composition, affecting
the post-intake glycemic response of this type of products in
healthy individuals.http://www.redalyc.org/articulo.oa?id=5594990800
Achieving Equity: An Evaluation of a Multi-Component, Lower Division Student Success Program
The purpose of this study was to evaluate an academic support program that aims to improve persistence and graduation for lower-division students who are low income, first generation, and/or underrepresented. Students were organized in 10 academies that serve as a “school within a school” and have three main elements: a pathway of two linked general education courses that students follow, cohort-style, over four semesters; wraparound student services integrated into the classroom; and a 45-hour faculty development process. Program participants (n = 2,281) were compared to a matched comparison group (n = 2,276). Multimodal logistic regression analyses showed that program participants statistically significantly outperformed the comparison group on every outcome measure: GPA, completion of developmental coursework, persistence toward graduation, and graduation rates
Individual and combined effects of chemical and mechanical power on postoperative pulmonary complications: a secondary analysis of the REPEAT study
Introduction: Intra-operative supplemental oxygen and mechanical ventilation expose the lungs to potentially injurious energy. This can be quantified as 'chemical power' and 'mechanical power', respectively. In this study, we sought to determine if intra-operative chemical and mechanical power, individually and/or in combination, are associated with postoperative pulmonary complications. Methods: Using an individual patient data analysis of three randomised clinical trials of intra-operative ventilation, we summarised intra-operative chemical and mechanical power using time-weighted averages. We evaluated the association between intra-operative chemical and mechanical power and a collapsed composite of postoperative pulmonary complications using multivariable logistic regression to estimate the odds ratios related to the effect of 1 J.min-1 increase in chemical or mechanical power with adjustment for demographic and intra-operative characteristics. We also included an interaction term to assess for potential synergistic effects of chemical and mechanical power on postoperative pulmonary complications. Results: Of 3837 patients recruited to three individual trials, 2492 with full datasets were included in the analysis. Intra-operative time-weighted average (SD) chemical power was 10.2 (3.9) J.min-1 and mechanical power was 10.5 (4.4) J.min-1. An increase of 1 J.min-1 in chemical power was associated with 8% higher odds of postoperative pulmonary complications (OR 1.08, 95%CI 1.05-1.10, p < 0.001), while the same increase in mechanical power raised odds by 5% (OR 1.05, 95%CI 1.02-1.08, p = 0.003). We did not find evidence of a significant interaction between chemical and mechanical power (p = 0.40), suggestive of an additive rather than synergistic effect on postoperative pulmonary complications. Discussion: Both chemical and mechanical power are independently associated with postoperative pulmonary complications. Further work is required to determine causality
Venezuela's humanitarian crisis, resurgence of vector-borne diseases, and implications for spillover in the region.
In the past 5-10 years, Venezuela has faced a severe economic crisis, precipitated by political instability and declining oil revenue. Public health provision has been affected particularly. In this Review, we assess the impact of Venezuela's health-care crisis on vector-borne diseases, and the spillover into neighbouring countries. Between 2000 and 2015, Venezuela witnessed a 359% increase in malaria cases, followed by a 71% increase in 2017 (411 586 cases) compared with 2016 (240 613). Neighbouring countries, such as Brazil, have reported an escalating trend of imported malaria cases from Venezuela, from 1538 in 2014 to 3129 in 2017. In Venezuela, active Chagas disease transmission has been reported, with seroprevalence in children (<10 years), estimated to be as high as 12·5% in one community tested (n=64). Dengue incidence increased by more than four times between 1990 and 2016. The estimated incidence of chikungunya during its epidemic peak is 6975 cases per 100 000 people and that of Zika virus is 2057 cases per 100 000 people. The re-emergence of many vector-borne diseases represents a public health crisis in Venezuela and has the possibility of severely undermining regional disease elimination efforts. National, regional, and global authorities must take action to address these worsening epidemics and prevent their expansion beyond Venezuelan borders
Divergence between sympatric rice- and maize-infecting populations of Rhizoctonia solani AG-1 IA from Latin America
ABSTRACT The basidiomycetous fungus Rhizoctonia solani anastomosis group (AG)-1 IA is a major pathogen in Latin America causing sheath blight (SB) of rice. Particularly in Venezuela, the fungus also causes banded leaf and sheath blight (BLSB) on maize, which is considered an emerging disease problem where maize replaced traditional rice-cropping areas or is now planted in adjacent fields. Our goals in this study were to elucidate (i) the effects of host specialization on gene flow between sympatric and allopatric rice and maize-infecting fungal populations and (ii) the reproductive mode of the fungus, looking for evidence of recombination. In total, 375 isolates of R. solani AG1 IA sampled from three sympatric rice and maize fields in Venezuela (Portuguesa State) and two allopatric rice fields from Colombia (Meta State) and Panama (Chiriquí State) were genotyped using 10 microsatellite loci. Allopatric populations from Venezuela, Colombia, and Panama were significantly differentiated (Phi(ST) of 0.16 to 0.34). Partitioning of the genetic diversity indicated differentiation between sympatric populations from different host species, with 17% of the total genetic variation distributed between hosts while only 3 to 6% was distributed geographically among the sympatric Venezuelan fields. We detected symmetrical historical migration between the rice- and the maize-infecting populations from Venezuela. Rice- and maize-derived isolates were able to infect both rice and maize but were more aggressive on their original hosts, consistent with host specialization. Because the maize- and rice-infecting populations are still cross-pathogenic, we postulate that the genetic differentiation was relatively recent and mediated via a host shift. An isolation with migration analysis indicated that the maize-infecting population diverged from the rice-infecting population between 40 and 240 years ago. Our findings also suggest that maize-infecting populations have a mainly recombining reproductive system whereas the rice-infecting populations have a mixed reproductive system in Latin America
Optimización de la estrategia de producción para las arenas R, T y U del área Mata
Las reservas de mayor dimensión en el Área Mata esta constituida por la arena U12, sin embargo, la misma contiene hidrocarburo que varía desde 21°API hasta 9°API en las zonas Zorro y Mata 3. Esta arena se caracteriza por poseer baja saturación de agua residual (8%), lo que permite su ubicación de una manera directa en los registros de pozos. Adicionalmente la permeabilidad de la misma no sobrepasa los 500mD, otra característica resaltante es el alto valor de la saturación de petróleo residual (35%), estas propiedades en definitiva afectan la extracción de este petróleo. En esta arena se presenta un fenómeno segregacional, poco común, que caracteriza la arena. Se dice que el mismo es poco común, pues en el yacimiento se encuentran divididos el petróleo pesado del extrapesado, debido a la presencia de una columna de agua procedente del acuífero localizado en las arenas U inferiores. Adicionalmente existe en el tope de la estructura una capa de gas original del yacimiento. El histórico de producción, indica que las reservas drenadas hasta el momento provienen del sector superior de la arena, sin embargo, tres pozos han producido del crudo extrapesado lo cual permite obtener un comportamiento aproximado de la declinación de la producción del fluido. Las zonas que contienen este hidrocarburo, poseen características petrofísicas bien diferencias, que afecta la producción del mismo, por esta razón la mayor producción acumulada se encuentra en la zona Zorro que posee las mejores propiedades de roca. La producción de estas reservas debe efectuarse por separado, ya que los crudos contenidos en el yacimiento tienen propiedades de fluido diferentes, especialmente la viscosidad. Los estudios técnicos demostraron que el bombeo electrosumergible es el método adecuado para la producción de crudo pesado de la zona de zorro, mientras que el levantamiento artificial por gas se recomienda para la extracción de este crudo en la zona Mata 3. En definitiva, la producción de crudo extrapesado para la arena de estudio, es el bombeo hidráulico tipo chorro, ya que no posee partes móviles que puedan afectarse por la producción de crudo viscoso, además permite disminuir la viscosidad del fluido debido a la mezcla con el fluido motriz que acciona el sistema, también permite monitorear la presión del yacimiento. En el Área existen otras arenas (TU y R0) que contienen crudo de las mismas características, sin embargo, las dimensiones y ausencia de información de estas arenas, no permitió establecer un plan estratégico de explotación
Mapping tsunami impacts on land cover and related ecosystem service supply in Phang Nga, Thailand
-The 2004 Indian Ocean tsunami caused damages to coastal ecosystems and thus affected the livelihoods of the coastal communities who depend on services provided by these ecosystems. The paper presents a case study on evaluating and mapping the spatial and temporal impacts of the tsunami on land use and land cover (LULC) and related ecosystem service supply in the Phang Nga province, Thailand. The method includes local stakeholder interviews, field investigations, remote-sensing techniques, and GIS. Results provide an ecosystem services matrix with capacity scores for 18 LULC classes and 17 ecosystem functions and services as well as pre-/post-tsunami and recovery maps indicating changes in the ecosystem service supply capacities in the study area. Local stakeholder interviews revealed that mangroves, casuarina forest, mixed beach forest, coral reefs, tidal inlets, as well as wetlands (peat swamp forest) have the highest capacity to supply ecosystem services, while e.g. plantations have a lower capacity. The remote-sensing based damage and recovery analysis showed a loss of the ecosystem service supply capacities in almost all LULC classes for most of the services due to the tsunami. A fast recovery of LULC and related ecosystem service supply capacities within one year could be observed for e.g. beaches, while mangroves or casuarina forest needed several years to recover. Applying multi-temporal mapping the spatial variations of recovery could be visualised. While some patches of coastal forest were fully recovered after 3 yr, other patches were still affected and thus had a reduced capacity to supply ecosystem services. The ecosystem services maps can be used to quantify ecological values and their spatial distribution in the framework of a tsunami risk assessment. Beyond that they are considered to be a useful tool for spatial analysis in coastal risk management in Phang Nga
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