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1.
J Stroke Cerebrovasc Dis ; 33(11): 107926, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39154784

RESUMEN

OBJECTIVES: A growing body of data indicates that extracranial carotid artery disease (ECAD) can contribute to cognitive impairment. However, there have been mixed reports regarding the benefit of carotid endarterectomy (CEA) as it relates to preserving cognitive function. In this work, diffusion magnetic resonance imaging (dMRI) and neurocognitive testing are used to provide insight into structural and functional brain changes that occur in subjects with significant carotid artery stenosis, as well as changes that occur in response to CEA. MATERIALS AND METHODS: The study design was a prospective, non-randomized, controlled study that enrolled patients with asymptomatic carotid stenosis. Thirteen subjects had severe ECAD (≥70% stenosis in at least one carotid artery) and were scheduled to undergo surgery. Thirteen had asymptomatic ECAD with <70% stenosis, therefore not requiring surgery. All subjects underwent neurocognitive testing using the Montreal Cognitive Assessment test (MoCA) and high angular resolution, multi-shell diffusion magnetic resonance imaging (dMRI) of the brain at baseline and at four-six months follow-up. Changes in MoCA scores as well as in Fractional anisotropy (FA) along the hippocampus were compared at baseline and follow-up. RESULTS: At baseline, FA was significantly lower along the ipsilateral hippocampus in subjects with severe ECAD compared to subjects without severe ECAD. MoCA scores were lower in these individuals, but this did not reach statistical significance. At follow-up, MoCA scores increased significantly in subjects who underwent CEA and remained statistically equal in control subjects that did not have CEA. FA remained unchanged in the CEA group and decreased in the control group. CONCLUSIONS: This study suggests that CEA improves cognition and preserves hippocampal white matter structure compared to control subjects not undergoing CEA.

2.
Agron Sustain Dev ; 43(6): 75, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37969112

RESUMEN

Early energy analyses of agriculture revealed that behind higher labor and land productivity of industrial farming, there was a decrease in energy returns on energy (EROI) invested, in comparison to more traditional organic agricultural systems. Studies on recent trends show that efficiency gains in production and use of inputs have again somewhat improved energy returns. However, most of these agricultural energy studies have focused only on external inputs at the crop level, concealing the important role of internal biomass flows that livestock and forestry recirculate within agroecosystems. Here, we synthesize the results of 82 farm systems in North America and Europe from 1830 to 2012 that for the first time show the changing energy profiles of agroecosystems, including livestock and forestry, with a multi-EROI approach that accounts for the energy returns on external inputs, on internal biomass reuses, and on all inputs invested. With this historical circular bioeconomic approach, we found a general trend towards much lower external returns, little or no increases in internal returns, and almost no improvement in total returns. This "energy trap" was driven by shifts towards a growing dependence of crop production on fossil-fueled external inputs, much more intensive livestock production based on feed grains, less forestry, and a structural disintegration of agroecosystem components by increasingly linear industrial farm managements. We conclude that overcoming the energy trap requires nature-based solutions to reduce current dependence on fossil-fueled external industrial inputs and increase the circularity and complexity of agroecosystems to provide healthier diets with less animal products. Supplementary Information: The online version contains supplementary material available at 10.1007/s13593-023-00925-5.

3.
Naturwissenschaften ; 106(11-12): 59, 2019 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-31758265

RESUMEN

Immune response is evolutionary costly, but it is not clear whether these costs affect energetic expenditure (short-term cost), growth (medium-term cost), or reproduction (long-term cost). We tested the costs of immune memory in Tenebrio molitor against Metarhizium brunneum. To do this, we used two groups of T. molitor larvae: (a) the control group, which was injected first with Tween solution and 10 days later with M. brunneum and (b) the memory group, which was first injected with M. brunneum and 10 days later with M. brunneum. Compared to controls, larvae of the memory group were more likely to survive, but they also had an increased metabolic rate (CO2 production), spent a long time before becoming pupae, and had a shorter time from pupae to adulthood. In the adult stage, control females preferred control males, but there was no significant difference in the preference of memory females. Finally, control and memory males preferred control females. These results confirm that immune memory has costs in terms of energetic expenditure, growth, and reproduction. To the best of our knowledge, this is the first experimental demonstration that immune memory in larvae is traded-off with adult sexual selection involving mate choice.


Asunto(s)
Estadios del Ciclo de Vida/inmunología , Tenebrio/inmunología , Tenebrio/microbiología , Animales , Metabolismo Energético , Femenino , Larva/inmunología , Larva/microbiología , Masculino , Metarhizium/inmunología
4.
Environ Sci Technol ; 53(9): 5091-5101, 2019 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-30939241

RESUMEN

Irrigation in the Mediterranean region has been used for millennia and has greatly expanded with industrialization. Irrigation is critical for climate change adaptation, but it is also an important source of greenhouse gas emissions. This study analyzes the carbon (C) footprint of irrigation in Spain, covering the complete historical process of mechanization. A 21-fold total, 6-fold area-based, and 4-fold product-based increase in the carbon footprint was observed during the 20th century, despite an increase in water use efficiency. CH4 emissions from waterbodies, which had not previously been considered in the C footprint of irrigation systems, dominated the emission budget during most of the analyzed period. Technologies to save water and tap new water resources greatly increased energy and infrastructure demand, while improvements in power generation efficiency had a limited influence on irrigation emissions. Electricity production from irrigation dams may contribute to climate change mitigation, but the amount produced in relation to that consumed in irrigation has greatly declined. High uncertainty in CH4 emission estimates from waterbodies stresses a need for more spatially resolved data and an improved empirical knowledge of the links between water quality, water level fluctuations, and emissions at the regional scale.


Asunto(s)
Huella de Carbono , Gases de Efecto Invernadero , Metano , España , Agua
5.
Reg Environ Change ; 18(4): 1089-1101, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-31258413

RESUMEN

Energy efficiency in biomass production is a major challenge for a future transition to sustainable food and energy provision. This study uses methodologically consistent data on agroecosystem energy flows and different metrics of energetic efficiency from seven regional case studies in North America (USA and Canada) and Europe (Spain and Austria) to investigate energy transitions in Western agroecosystems from the late nineteenth to the late twentieth centuries. We quantify indicators such as external final energy return on investment (EFEROI, i.e., final produce per unit of external energy input), internal final EROI (IFEROI, final produce per unit of biomass reused locally), and final EROI (FEROI, final produce per unit of total inputs consumed). The transition is characterized by increasing final produce accompanied by increasing external energy inputs and stable local biomass reused. External inputs did not replace internal biomass reinvestments, but added to them. The results were declining EFEROI, stable or increasing IFEROI, and diverging trends in FEROI. The factors shaping agroecosystem energy profiles changed in the course of the transition: Under advanced organic and frontier agriculture of the late nineteenth and early twentieth centuries, population density and biogeographic conditions explained both agroecosystem productivity and energy inputs. In industrialized agroecosystems, biogeographic conditions and specific socio-economic factors influenced trends towards increased agroecosystem specialization. The share of livestock products in a region's final produce was the most important factor determining energy returns on investment.

6.
J Exp Biol ; 219(Pt 22): 3665-3669, 2016 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-27618859

RESUMEN

Parasites can be transmitted vertically and/or horizontally, but the costs or benefits for the host of infection have only been tested after horizontal transmission. Here, we report for the first time, to our knowledge, the survival, reproduction and infection of Aedes aegypti during vertical and horizontal transmission of dengue virus 2 (DENV-2). Females infected horizontally produced more eggs, with a sex ratio skewed towards males, compared with uninfected controls. However, there was no significant difference in the number of emerging adults or in survival of mothers. In contrast, dengue-infected female offspring (vertical transmission) had a shorter lifespan but there were no significant differences in the number of eggs or sex ratio, compared with controls. Finally, the corroboration of infection revealed that virus infected about 11.5% and 8.8% of pools of mothers and of daughters, respectively. These results suggest that the mode of infection and the contact with the virus has no reproductive costs to female mosquitoes, which may explain why both types of transmission are evolutionarily maintained. In addition, we suggest that more attention should be paid to the male contribution to virus dissemination within and among populations and as reservoirs of the infection for human diseases.


Asunto(s)
Virus del Dengue/fisiología , Dengue/transmisión , Transmisión de Enfermedad Infecciosa , Transmisión Vertical de Enfermedad Infecciosa , Aedes/virología , Animales , Femenino , Masculino , Óvulo/fisiología , Conejos , Razón de Masculinidad , Análisis de Supervivencia
7.
Sci Total Environ ; 949: 174859, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39053548

RESUMEN

The world's top ten Organic Farming (OF) countries by converted area include several Mediterranean countries, including Spain. Despite this, little is known about the consequences of OF on crop production and environmental sustainability in this country. In this article, we conduct an agronomic analysis of Spanish considerable conversion rate to OF, which tends to concentrate in certain provinces and crops. Indeed, in the case of various crops and in several provinces, the organic share of total agricultural land exceeds 20-30 %. This concentration makes it possible to compare information obtained from farmers through interviews and provincial statistical information. The study data consisted of information collected from interviews of a representative sample of organic farmers conducted in 2004 and 2020 as well as official statistical information. The results showed that no yield gap between OF and conventional farming was found for vegetables and fruit trees, while it showed an increasing trend in arable crops. Presumably, the reason is that fruit trees and vegetables generate and incorporate high levels of carbon (C) flows into the soil and have a low land cost per unit of incorporated nitrogen (N) (or can be paid for), allowing to meet crop needs and to increase soil organic matter (SOM). Conversely, in the case of rainfed arable crops, the soil C and N inputs are deficient due to the low crop residues and the high land cost of N. Consequently, SOM destruction and N deficit progressively broaden the yield gap, undermining the agroecosystem sustainability. To reverse the situation, among other measures, it is necessary to implement agricultural policies designed to make rotations with high legume ratios viable and to plant varieties presenting higher production of residues and roots, such as traditional varieties.


Asunto(s)
Carbono , Productos Agrícolas , Nitrógeno , Agricultura Orgánica , España , Nitrógeno/análisis , Carbono/análisis , Agricultura Orgánica/métodos , Suelo/química , Agricultura/métodos , Conservación de los Recursos Naturales/métodos , Producción de Cultivos/métodos
8.
Evol Appl ; 17(6): e13738, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38919879

RESUMEN

The Africanized honey bee, a hybrid of Apis mellifera scutellata from Africa with European subspecies, has been considered an invasive species and a problem for beekeeping. Africanized bees arrived in Mexico in 1986, 30 years after their accidental release in Brazil. Although government programs were implemented for its eradication, Africanized populations persist in Mexico, but precise information on the patterns of genetic introgression and racial ancestry is scarce. We determined maternal and parental racial ancestry of managed and feral honey bees across the five beekeeping regions of Mexico, using mitochondrial (mtDNA, COI-COII intergenic region) and nuclear markers (94 ancestrally informative SNPs), to assess the relationship between beekeeping management, beekeeping region, altitude, and latitude with the distribution of maternal and parental racial ancestry. Results revealed a predominantly African ancestry in the Mexican honey bees, but the proportion varied according to management, beekeeping regions, and latitude. The Mexican honey bees showed 31 haplotypes of four evolutionary lineages (A, M, C, and O). Managed honey bees had mitochondrial and nuclear higher proportions of European ancestry than feral honey bees, which had a higher proportion of African ancestry. Beekeeping regions of lower latitudes had higher proportions of African nuclear ancestry. Managed and feral honey bees showed differences in the proportion of maternal and nuclear racial ancestry. Managed honey bees from the Yucatan Peninsula and feral honey bees had a higher mtDNA than nuclear proportions of African ancestry. Managed honey bees, except those on the Yucatan Peninsula, had a higher nuclear than mtDNA proportion of African ancestry. Our study demonstrates that Africanized honey bee populations are genetically diverse and well established in Mexico, which highlights the limitations of management and government programs to contain the Africanization process and demands the incorporation of this lineage in any breeding program for sustainable beekeeping.

9.
Ecol Evol ; 14(6): e11456, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38895569

RESUMEN

The decline of honey bee populations significantly impacts the human food supply due to poor pollination and yield decreases of essential crop species. Given the reduction of pollinators, research into critical landscape components, such as floral resource availability and land use change, might provide valuable information about the nutritional status and health of honey bee colonies. To address this issue, we examine the effects of landscape factors like agricultural area, urban area, and climatic factors, including maximum temperature, minimum temperature, relative humidity, and precipitation, on honey bee hive populations and nutritional health of 326 honey bee colonies across varying landscapes in Mexico. DNA metabarcoding facilitated the precise identification of pollen from 267 plant species, encompassing 243 genera and 80 families, revealing a primary herb-based diet. Areas characterized by high landscape diversity exhibited greater pollen diversity within the colony. Conversely, colonies situated in regions with higher proportions of agricultural and urban landscapes demonstrated lower bee density. The maximum ambient temperature outside hives positively correlated with pollen diversity, aligning with a simultaneous decrease in bee density. Conversely, higher relative humidity positively influenced both the bee density of the colony and the diversity of foraged pollen. Our national-level study investigated pollen dietary availability and colony size in different habitat types, latitudes, climatic conditions, and varied levels and types of disturbances. This effort was taken to gain a better insight into the mechanisms driving declines in honey bee populations. This study illustrates the need for more biodiverse agricultural landscapes, the preservation of diverse habitats, and the conservation of natural and semi-natural spaces. These measures can help to improve the habitat quality of other bee species, as well as restore essential ecosystem processes, such as pollination and pest control.

10.
Artículo en Inglés | MEDLINE | ID: mdl-36674397

RESUMEN

Official population consumption data are frequently used to characterize the diet of countries; however, this information may not always be representative of reality. This study analyses the food consumption of the Spanish population by reconstructing the whole food chain. The results have been compared with the data provided by the National Consumption Panel to which the food losses/waste reported in the literature along the distribution chain have been added. The difference between them allowed a new calculation of the estimated food consumption that was subjected to a dietary-nutritional analysis. Most of the foods were consumed more than those officially reported (range of 5-50%). The unhealthy ratios of consumed foods and recommended servings were: meat products (Rcr = 3.6), fruits and legumes (Rcr = 0.5), and nuts (Rcr = 0.14). Caloric intake surpasses needs. The results were consistent with the data on the prevalence of overweight and obesity in Spain, as well as with the prevalence of associated diseases. To make a judgment about the quality of a country's diet, it is necessary to have reliable data on food consumption, as well as energy and nutrient intake. This study encourages other authors to implement this method to verify and quantify the possible difference between official and real consumption data.


Asunto(s)
Dieta , Obesidad , Obesidad/epidemiología , Ingestión de Energía , Verduras , Frutas
11.
Dev Comp Immunol ; 138: 104528, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36067906

RESUMEN

Invertebrates' immune priming or innate immune memory is an analogous response to the vertebrates' adaptive memory. We investigated if honey bees have immune memory. We compared survival and immune response between bees that were: 1) manipulated (Naïve), 2) challenged twice with the same pathogen Escherichia coli (Memory), 3) challenged twice with different pathogens (Staphylococcus aureus versus E. coli, Micrococcus lysodeikticus versus E. coli), or 4) with PBS (the diluent of bacteria) versus E. coli (heterologous challenge; Control). Results indicate better survival in the Memory than the Control group, and the Memory group showed a similar survival than Naïve insects. The Memory group had higher lytic activity but lower prophenoloxidase, phenoloxidase activity, and hemocyte count than the Control and Naïve groups. No differences were found in relative expression of defensin-1. This first demonstration of immune memory opens the questions about its molecular mechanisms and whether, immune memory could be used against natural parasites that affect honey bees, hence, if they could be "vaccinated" against some natural parasites.


Asunto(s)
Escherichia coli , Monofenol Monooxigenasa , Animales , Abejas , Defensinas , Escherichia coli/metabolismo , Hemocitos/metabolismo , Memoria Inmunológica , Monofenol Monooxigenasa/metabolismo
12.
Artículo en Inglés | MEDLINE | ID: mdl-36610635

RESUMEN

Hormones are key factors in determining the response of organisms to their environment. For example, the juvenile hormone (JH) coordinates the insects' development, reproduction, and survival. However, it is still unclear how the impact of juvenile hormone on insect immunity varies depending on the sex and reproductive state of the individual, as well as the type of the immune challenge (i.e., Gram-positive or Gram-negative bacteria). We used Tenebrio molitor and methoprene, a JH analog (JHa) to explore these relationships. We tested the effect of methoprene on phenoloxidase activity (PO), an important component of humoral immunity in insects, and hemocyte number. Lyophilized Gram-positive Staphylococcus aureus or Gram-negative Escherichia coli were injected for the immune challenge. The results suggest that JH did not affect the proPO, PO activity, or hemocyte number of larvae. JH and immune challenge affected the immune response and consequently, affected adult developmental stage and sex. We propose that the influence of JH on the immune response depends on age, sex, the immune response parameter, and the immune challenge, which may explain the contrasting results about the role of JH in the insect immune response.


Asunto(s)
Hormonas Juveniles , Metopreno , Animales , Hormonas Juveniles/farmacología , Monofenol Monooxigenasa , Hemocitos , Reproducción
13.
Sci Rep ; 13(1): 1017, 2023 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-36653357

RESUMEN

Honey bee decline is currently one of the world's most serious environmental issues, and scientists, governments, and producers have generated interest in understanding its causes and consequences in honey production and food supply. Mexico is one of the world's top honey producers, however, the honey bee population's status has not been documented to date. Based on 32 years of data from beekeeping, we make a country-level assessment of honey bee colony trends in Mexico. We use generalized additive mixed models to measure the associations between the percent change in honey bee hives and the percent change in honey yield per hive in relation to land-use, climate, and socioeconomic conditions. Despite the fact that the average annual yield per hive increased from 1980 to 2012, we detected a significant decline in the percent change in the number of honey bee hives across the time period studied. We also found a relationship between climatic conditions and agricultural land use, with agriculture increases and high temperatures producing a decrease in the percent change in honey yield. We found a relationship between a reduction in the temperature range (the difference between maximum and minimum temperatures) and a decrease in the percent change in the number of hives, while socioeconomic factors related to poverty levels have an impact on the number of hives and honey yields. Although long-term declines in hive numbers are not correlated with poverty levels, socioeconomic factors in states with high and medium poverty levels limit the increase in honey yield per hive. These results provide evidence that land-use changes, unfavorable climatic conditions, political, and socioeconomic factors are partially responsible for the reductions in the percent change in honey bee hives in Mexico.


Asunto(s)
Agricultura , Miel , Abejas , Animales , México , Apicultura , Factores Socioeconómicos
14.
Sci Total Environ ; 621: 634-648, 2018 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-29202285

RESUMEN

Soil organic carbon (SOC) management is key for soil fertility and for mitigation and adaptation to climate change, particularly in desertification-prone areas such as Mediterranean croplands. Industrialization and global change processes affect SOC dynamics in multiple, often opposing, ways. Here we present a detailed SOC balance in Spanish cropland from 1900 to 2008, as a model of a Mediterranean, industrialized agriculture. Net Primary Productivity (NPP) and soil C inputs were estimated based on yield and management data. Changes in SOC stocks were modeled using HSOC, a simple model with one inert and two active C pools, which combines RothC model parameters with humification coefficients. Crop yields increased by 227% during the studied period, but total C exported from the agroecosystem only increased by 73%, total NPP by 30%, and soil C inputs by 20%. There was a continued decline in SOC during the 20th century, and cropland SOC levels in 2008 were 17% below their 1933 peak. SOC trends were driven by historical changes in land uses, management practices and climate. Cropland expansion was the main driver of SOC loss until mid-20th century, followed by the decline in soil C inputs during the fast agricultural industrialization starting in the 1950s, which reduced harvest indices and weed biomass production, particularly in woody cropping systems. C inputs started recovering in the 1980s, mainly through increasing crop residue return. The upward trend in SOC mineralization rates was an increasingly important driver of SOC losses, triggered by irrigation expansion, soil cover loss and climate change-driven temperature rise.

15.
PLoS One ; 13(6): e0198349, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29933375

RESUMEN

Functional magnetic resonance imaging (fMRI) is an important tool for pre-surgical evaluation of eloquent cortex. Classic task-based paradigms require patient participation and individual imaging sequence acquisitions for each functional domain that is being assessed. Resting state fMRI (rs-fMRI), however, enables functional localization without patient participation and can evaluate numerous functional domains with a single imaging session. To date, post-processing of this resting state data has been resource intensive, which limits its widespread application for routine clinical use. Through a novel automated algorithm and advanced imaging IT structure, we report the clinical application and the large-scale integration of rs-fMRI into routine neurosurgical practice. One hundred and ninety one consecutive patients underwent a 3T rs-fMRI, 83 of whom also underwent both motor and language task-based fMRI. Data were processed using a novel, automated, multi-layer perceptron algorithm and integrated into stereotactic navigation using a streamlined IT imaging pipeline. One hundred eighty-five studies were performed for intracranial neoplasm, 14 for refractory epilepsy and 33 for vascular malformations or other neurological disorders. Failure rate of rs-fMRI of 13% was significantly better than that for task-based fMRI (38.5%,) (p <0.001). In conclusion, at Washington University in St. Louis, rs-fMRI has become an integral part of standard imaging for neurosurgical planning. Resting state fMRI can be used in all patients, and due to its lower failure rate than task-based fMRI, it is useful for patients who are unable to cooperate with task-based studies.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Corteza Cerebral/diagnóstico por imagen , Epilepsia Refractaria/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Enfermedades del Sistema Nervioso/diagnóstico por imagen , Malformaciones Vasculares/diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Niño , Preescolar , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Masculino , Persona de Mediana Edad , Periodo Preoperatorio , Descanso , Adulto Joven
16.
J Virol Methods ; 137(2): 334-8, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16857274

RESUMEN

RT-PCR is the most sensitive assay for the detection of human caliciviruses (HuCV) in stool and environmental samples. However, false negative results are commonly obtained due to the presence of RT-PCR inhibitors. In order to exclude such false negative results, an internal control (IC) was developed for the assay by cloning a 319 nt sequence of the Norwalk virus (NV) polymerase containing a 156 nt cDNA insert. The RT-PCR assay was carried out using RNA derived from the constructed plasmid and a primer set previously described for calicivirus detection, resulting in a 475 nt product. Distinct bands of the internal control and the viral specific RT-PCR products (319 nt) were obtained when the internal control was added to the samples. Similar results were also obtained when both the control RNA and viral RNA were seeded into stool samples from asymptomatic volunteers, or when the internal control was included into positive samples. Since the primer set used in the assays can detect a wide range of strains in both norovirus and sapovirus genera, this internal control should have a broad application for the diagnosis of human caliciviruses diagnosis in both clinical and environmental samples.


Asunto(s)
Infecciones por Caliciviridae/virología , Heces/virología , Virus Norwalk/aislamiento & purificación , ARN Viral/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/normas , Infecciones por Caliciviridae/diagnóstico , ADN Complementario , Genes pol , Humanos , Virus Norwalk/genética , ARN Viral/genética , Estándares de Referencia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos
18.
Insect Sci ; 20(5): 620-8, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23956189

RESUMEN

It has been proposed that given that males should invest in sexual traits at the expense of their investment in immune response, females are better immunocompetent than males. Typically, this idea has been tested in monomorphic species, but rarely has been evaluated in polymorphic male species. We used Paraphlebia zoe, a damselfly with two male morphs: the black-winged morph (Black-W) develop black spots as sexual traits and the hyaline-winged morph (Hyaline-W) resembles a female in size and wings color. We predicted that Black-W should have a lower immune response than Hyaline-W, but that the latter males should not differ from females in this respect. Nitric oxide (NO) and phenoloxidase (PO) production, as well as hemolymph protein content, were used as immune markers. Body size (wing length) was used as an indicator of the male condition. The results show that, as we predicted, females and Hyaline-W had higher values of NO than Black-W, corresponding to differences in size. However, the opposite was found in relation to PO production. Females had the highest levels of hemolymph protein content, whereas no differences were found between Black-W and Hyaline-W. These results partially support the sexual selection hypothesis and are discussed in the context of the life history of this species. Black-W, Hyaline-W, and females could express the immune markers that are prioritized by their particular condition, and probably neither of them could express all immune markers in an elevated manner, as this would result in an excessive accumulation of free radicals.


Asunto(s)
Odonata/fisiología , Animales , Tamaño Corporal , Femenino , Masculino , Pigmentos Biológicos , Caracteres Sexuales , Alas de Animales/fisiología
19.
Infectio ; 14(1): 31-38, mar. 2010. tab
Artículo en Español | LILACS | ID: lil-560936

RESUMEN

Introducción: Los parásitos intestinales se consideran un problema de salud pública en los países en desarrollo y afecta a individuos de todas las edades y sexos, pero se presentan, sobre todo, en los primeros años de vida. En la actualidad, entre las parasitosis más reportadas para el departamento del Quindío se encuentra la giardiasis, producida por Giardia intestinalis (G. duodenalis o G. lamblia), y la blastocistocis, producida por Blastocystis sp. Objetivo: Determinar la prevalencia de protozoos intestinales en 79 niños con edades comprendidas entre los 2 y 5 años, de un hogar infantil en el municipio de Circasia, Quindío.Materiales y métodos: Se recolectaron tres muestras de heces en 79 niños con previo consentimiento del tutor legal. Las muestras fueron sometidas al análisis de laboratorio por examen directo macroscópico y microscópico, utilizando lugol al 1%, solución salina al 0,83%, solución salina-eosina y la técnica de concentración de Ritchie o formol-éter. Resultados: Para los tres muestras, los parásitos con potencial patógeno tuvieron las siguientes prevalencias: Blastocystis sp., 49,4%, 57% y 64,6%; G. lamblia, 16,5%, 22,8% y 15,2 %; complejo Entamoeba histolytica/dispar, 5,1%, 5,1% y 1,3%, respectivamente. Conclusiones: Este estudio muestra la elevada prevalencia de parásitos protozoarios, y Blastocystis sp. fue el más prevalente. Durante el seguimiento se detectó reinfestación de los niños que participaron en el estudio.


Introduction: Intestinal parasites are considered a public health problem in developing countries, and they affect individuals of all ages and sexes; nevertheless they are frequent in early childhood. At present, the most reported intestinal parasite conditions in Quindío are giardiasis, caused by Giardia intestinalis (G. lamblia or G.duodenalis), and blastocystosis caused by Blastocystis sp. Objective: The objective is to determine the prevalence of intestinal parasites in children 2 to 5 years old at a State nursery in Circasia, Quindio. Materials and methods: Three fecal samples per child were collected from 79 children following informed consent from their legal guardians. Microscopic and macroscopic laboratory test were made using 1 % Lugol, 0,8 % saline solution, saline-eosin solution and concentration techniques with formaldehyde-ether (Ritchie.) Results: In the three fecal samples, the pathogen parasites had the following prevalence: Blastocystis sp 49,4 %, 57 % and 64,6 % sp; Giardia lamblia 16,5 %, 22,8 % and 15,2 %; and Entamoeba histolytica/dispar 5,1 %, 5,1 % and.1,3 % respectively.Conclusions: This study shows a high frequency of protozoa parasites, Blastocystis sp being the most prevalent. Re-infection in children was detected during the study.


Asunto(s)
Giardiasis , Preescolar , Prevalencia , Anticuerpos Antiprotozoarios
20.
Rev. Fac. Cienc. Méd. (Quito) ; 24(1): 27-30, sept. 1999. graf
Artículo en Español | LILACS | ID: lil-278924

RESUMEN

La amplificación del DNA del kinetoplasto, cada vez tiene mayor aplicación en la detección Leishmania y diagnóstico de leishmaniasis. En el presente estudio se emplea un par de sondas: KIN 1 y KIN 2, que se amplificaron en todas las especies de Leishmania, tanto las cepas de referencia como las aisladas a partir de lesiones en humanos, en quienes se observó un segmento de 470 pares de bases (pb), mientras que en Trypanosoma cruzi, un segmento de 520 pb. Es importante recalcar la necesidad de validar la utilidad de esta prueba en el diagnóstico clínico, epidemiológico y entomológico de esta enfermedad.


Asunto(s)
Reacción en Cadena de la Polimerasa
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