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1.
PLoS Negl Trop Dis ; 13(4): e0007322, 2019 04.
Article in English | MEDLINE | ID: mdl-30995228

ABSTRACT

Arboviral disease transmission by Aedes mosquitoes poses a major challenge to public health systems in Ecuador, where constraints on health services and resource allocation call for spatially informed management decisions. Employing a unique dataset of larval occurrence records provided by the Ecuadorian Ministry of Health, we used ecological niche models (ENMs) to estimate the current geographic distribution of Aedes aegypti in Ecuador, using mosquito presence as a proxy for risk of disease transmission. ENMs built with the Genetic Algorithm for Rule-Set Production (GARP) algorithm and a suite of environmental variables were assessed for agreement and accuracy. The top model of larval mosquito presence was projected to the year 2050 under various combinations of greenhouse gas emissions scenarios and models of climate change. Under current climatic conditions, larval mosquitoes were not predicted in areas of high elevation in Ecuador, such as the Andes mountain range, as well as the eastern portion of the Amazon basin. However, all models projected to scenarios of future climate change demonstrated potential shifts in mosquito distribution, wherein range contractions were seen throughout most of eastern Ecuador, and areas of transitional elevation became suitable for mosquito presence. Encroachment of Ae. aegypti into mountainous terrain was estimated to affect up to 4,215 km2 under the most extreme scenario of climate change, an area which would put over 12,000 people currently living in transitional areas at risk. This distributional shift into communities at higher elevations indicates an area of concern for public health agencies, as targeted interventions may be needed to protect vulnerable populations with limited prior exposure to mosquito-borne diseases. Ultimately, the results of this study serve as a tool for informing public health policy and mosquito abatement strategies in Ecuador.


Subject(s)
Aedes/physiology , Climate Change , Ecosystem , Models, Biological , Aedes/virology , Animals , Arboviruses , Ecuador , Larva , Mosquito Vectors/physiology , Mosquito Vectors/virology
2.
Acta méd. colomb ; 42(1): 30-34, ene.-mar. 2017. tab, graf
Article in Spanish | LILACS, COLNAL | ID: biblio-886336

ABSTRACT

Resumen Introducción: los factores de riesgo cardiovascular aparecen tempranamente en la niñez y adolescencia. Los principales son: hipertensión arterial, obesidad, la dieta inadecuada, el sedentarismo, el alcoholismo y el tabaquismo. Objetivo: determinar la prevalencia de factores de riesgo cardiovascular en adolescentes del Colegio Nacional de Enseñanza Media Diversificada de Itá (Paraguay) que asistieron al control clínico en meses de marzo y abril del 2015. Metodología: estudio observacional, descriptivo, prospectivo, de corte transversal que incluyó a 132 adolescentes de ambos sexos. Resultados: las prevalencias fueron: hipertensión arterial sistólica 1.5%, sobrepeso 8.3%, obesidad 2.7%, sedentarismo 58.3%, tabaquismo 6.8% y han tomado alcohol ocasionalmente 47.7%. El sobrepeso y la obesidad no mostraron relación estadísticamente significativa con las cifras elevadas de presión arterial. Conclusiones: la prevalencia de hipertensión arterial y exceso de peso encontradas fueron bajas. Llama la atención la alta frecuencia de bajo peso y la tendencia al sedentarismo. Entre los tabaquistas, dos tercios corresponden al sexo femenino.


Abstract Introduction: cardiovascular risk factors appear early in childhood and adolescence. The main ones are: arterial hypertension, obesity, inadequate diet, sedentary lifestyle, alcoholism and smoking. Objective: to determine the prevalence of cardiovascular risk factors in adolescents of the National School of Diversified Middle Education of Itá (Paraguay) who attended clinical control in March and April 2.015. Methodology: observational, descriptive, prospective, cross-sectional study that included 132 adolescents of both sexes. Results: prevalences were: systolic arterial hypertension 1.5%, overweight 8.3%, obesity 2.7%, sedentary lifestyle 58.3%, smoking 6.8% and occasional alcohol consumption 47.7%. Overweight and obesity did not show a statistically significant relationship with high blood pressure. Conclusions: the prevalence of arterial hypertension and excess weight found were low. Draws attention the high frequency of low weight and the tendency to sedentarism. Among smokers, twothirds correspond to women.


Subject(s)
Humans , Male , Female , Adolescent , Heart Disease Risk Factors , Tobacco Use Disorder , Adolescent , Alcoholism , Hypertension , Obesity
3.
Neurol Neuroimmunol Neuroinflamm ; 4(2): e324, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28105460

ABSTRACT

OBJECTIVE: To prospectively evaluate the validity of a PCR assay in CSF for the diagnosis of neurocysticercosis (NC). METHODS: We conducted a multicenter, prospective case-control study, recruiting participants from 5 hospitals in Cuenca, Ecuador, from January 2015 to February 2016. Cases fulfilled validated diagnostic criteria for NC. For each case, a neurosurgical patient who did not fulfill the diagnostic criteria for NC was selected as a control. CT and MRI, as well as a CSF sample, were collected from both cases and controls. The diagnostic criteria to identify cases were used as a reference standard. RESULTS: Overall, 36 case and 36 control participants were enrolled. PCR had a sensitivity of 72.2% (95% confidence interval [CI] 54.8%-85.8%) and a specificity of 100.0% (95% CI 90.3%-100.0%). For parenchymal NC, PCR had a sensitivity of 42.9% (95% CI 17.7%-71.1%), and for extraparenchymal NC, PCR had a sensitivity of 90.9% (95% CI 70.8%-98.9%). CONCLUSIONS: This study demonstrated the usefulness of this PCR assay in CSF for the diagnosis of NC. PCR may be particularly helpful for diagnosing extraparenchymal NC when neuroimaging techniques have failed. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that CSF PCR can accurately identify patients with extraparenchymal NC.

4.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1390089

ABSTRACT

Introducción: la hepatitis B (HB) sigue siendo un importante problema de Salud Pública debido a las consecuencias que acarrea en los pacientes infectados. Entre los grupos de alto riesgo de adquirir este virus se encuentran los pacientes con enfermedad renal crónica (ERC) en tratamiento hemodialítico, por lo que la vacunación constituye un importante método de prevención y protección contra el virus de la hepatitis B (VHB). Objetivos: determinar el nivel de antiHBsAg y hallar la prevalencia de respuesta inadecuada a la vacuna contra la HB. Detectar los factores de riesgo asociados a la falta de respuesta inmunológica a la vacuna contra HB. Metodología: estudio observacional, descriptivo, prospectivo, de corte transverso, con componente analítico. Se incluyeron pacientes adultos con ERC en tratamiento hemodialítico trisemanal del Hospital Nacional de Itauguá durante el 2015. A todos se les determinó antiHBsAg. Resultados: se incluyeron 89 sujetos, de los cuales 47% tuvieron una respuesta inadecuada a la vacuna contra el VHB, con un leve predominio del sexo masculino. Conclusiones: la frecuencia de respuesta inadecuada a la vacuna es 47%. La edad, el hábito tabáquico, las comorbilidades y el estado de nutrición por IMC resultaron como factores de riesgo no significativos en la respuesta inadecuada a la vacuna contra el VHB, mientras que los años de hemodiálsis y la uremia se relacionaron de manera significativa a esta mala respuesta.


Introduction: Hepatitis B (HB) is still an important problem of Public Health due to the consequences in the infected patients. Among the groups with high risk of acquiring this virus, there are the patients with chronic renal disease (CRD) receiving hemodialysis treatment. Vaccination is an important prevention and protection method against the hepatitis B virus (HBV). Objectives:To determine the level of anti-HBsAg, find the prevalence of inadequate response to the HB vaccine and detect the risk factors associated with the lack of immunological response to HB vaccine. Methodology: This was a cross-sectional prospective descriptive observational study with analytical component. Adult patients with CRD receiving hemodialysis treatment three times a week in the National Hospital of Itauguá during 2015 were included. Anti-HBsAg was determined in all of them. Results: Eighty nine patients were included and 47% of them had inadequate response to HB vaccine with a slight predominance of men. Conclusions: The frequency of inadequate response to the vaccine was 47%. Age, smoking habits, co-morbidities and nutritional state by BMI were non-significant risk factors in the inadequate response to HB vaccine while years of hemodialysis and uremia were significantly related to this bad response.

5.
Maturitas ; 82(1): 50-5, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26044074

ABSTRACT

People aged 60 and older represent over 11% of the world population and it is expected to rise 22% by 2050. Population aging is associated to an increased frequency of age-related diseases including higher susceptibility to infections, cancer, cardiovascular and neurodegenerative diseases. Immunosenescence refers to the decline of the immune system associated to aging. It affects both, innate and adaptive immunity limiting the response to pathogens and to vaccines. The analyses of the immune system in elderly individuals determined several immune signatures constituting an immune risk phenotype that predicts mortality. An inverse CD4/CD8 ratio, loss of naïve T cells, increased numbers of terminally-differentiated T cells and oligoclonal expansions of virus-specific T cells constitute hallmarks of immunosenescence. Natural killer (NK) cells are also found severely altered in the elderly. The contribution of latent cytomegalovirus infection to immunosenescence of T and NK cells has been shown. Considering the worldwide ageing of the population in the next decades, the impact of infections will be a real health problem for older individuals requiring preventive strategies. Thus, further studies are required to analyse the bases of immunosenescence and to establish protocols to overcome the age-associated alterations of the immune response in order to define effective vaccines against those pathogens, such as influenza, contributing to increased morbidity and mortality in the elderly.


Subject(s)
Aging/immunology , Cytomegalovirus Infections/immunology , Immunosenescence/physiology , Vaccination , Aged , Aged, 80 and over , Disease Susceptibility , Female , Humans , Male , T-Lymphocytes/immunology
6.
Biogerontology ; 16(5): 671-83, 2015 Oct.
Article in English | MEDLINE | ID: mdl-25991472

ABSTRACT

Human natural killer (NK) cells are innate lymphoid cells with capacity to kill tumor cells and virus-infected cells. According to the expression of CD56 and CD16 several NK cell subsets have been identified, a major CD56dimCD16+ subpopulation characterized by higher cytotoxic capacity, two CD56bright subsets (CD16-and CD16+) that represent different maturation stages and the fourth CD56-CD16+ subset that correspond to activated dysfunctional NK cells. Previous studies have shown quantitative changes in the frequency, phenotype and distribution of NK cell subsets depending on CMV-serostatus and age. We have analyzed the expression of NKp30, NKp46 and DNAM-1 NK activating receptors on resting and IL-2 activated NK cells from CMV-seronegative and seropositive healthy young donors and from CMV-seropositive elderly individuals. Our results showed that CMV-serostatus of healthy young donors is associated with phenotypic differences on both CD56bright and CD56dim NK cells with an increase of NKp46 and a decrease of NKp30 expression respectively. A reduced expression of DNAM-1 related to ageing and a lower NKp30 expression associated with CMV-seropositivity were observed. The expression of NKp46 and NKp30 was lower in CD57+ NK cells while the expression of DNAM-1 was increased. In vitro NK cell activation by IL-2 increased the expression of NKp46 and NKp30. In summary, both age and CMV-serostatus influence the expression of these cytotoxicity activating receptors that will have functional consequences. In elderly donors is difficult to isolate age from the effect of chronic CMV infection since in our study all elderly donors were CMV-seropositive. The possibility of modulating the expression of these activating receptors by cytokines such as IL-2 may open new opportunities for improving age-associated deterioration of NK cell function.


Subject(s)
Aging/immunology , Antigens, Differentiation, T-Lymphocyte/immunology , Cytomegalovirus Infections/immunology , Interleukin-2/pharmacology , Killer Cells, Natural/drug effects , Natural Cytotoxicity Triggering Receptor 1/immunology , Natural Cytotoxicity Triggering Receptor 3/immunology , Adult , Age Factors , Aged , Aging/blood , Antigens, Differentiation, T-Lymphocyte/blood , Case-Control Studies , Cells, Cultured , Child, Preschool , Cytomegalovirus/immunology , Cytomegalovirus/pathogenicity , Cytomegalovirus Infections/blood , Cytomegalovirus Infections/diagnosis , Cytomegalovirus Infections/virology , Female , Host-Pathogen Interactions , Humans , Immunophenotyping , Killer Cells, Natural/immunology , Killer Cells, Natural/metabolism , Killer Cells, Natural/virology , Male , Middle Aged , Natural Cytotoxicity Triggering Receptor 1/blood , Natural Cytotoxicity Triggering Receptor 3/blood , Phenotype , Serologic Tests
7.
Med. segur. trab ; 60(236): 587-599, jul.-sept. 2014. tab
Article in Spanish | IBECS | ID: ibc-131443

ABSTRACT

El desarrollo de las TIC favoreció la aparición del Teletrabajo (TT) a mediados del siglo pasado, pero actualmente, tan sólo el 13,2% de las empresas españolas lo fomentan. Las diferencias culturales, sociales, y las dificultades para homogeneizar la información disponible, hacen que resulte un desafío unificar criterios para su desarrollo. Esta revisión bibliográfica pretende mostrar el marco global del TT en España, factores de riesgo, repercusión, beneficios y perjuicios, detallar las condiciones y medidas de seguridad laboral que deberían acompañar el proceso. Para obtener los artículos se ha realizado una búsqueda bibliográfica en las principales bases de datos biomédicas. Efectos beneficiosos evidenciados serían el alto nivel de autonomía, elevada satisfacción laboral, mejor relación con el supervisor, disminución de la tasa de abandono del trabajo y del conflicto familiar. Otras publicaciones indican que reforzando los recursos personales, mejora el compromiso y la eficacia de los trabajadores. Se destaca la escasa existencia de descriptores específicos DeCS-MeSH para TT, incluidos en las bases de datos bibliográficas que utilizan estos tesauros como motor de búsqueda, Medline, Cochrane Library e IBECS, lo que dificulta la recuperación de información. El desconocimiento general sobre esta modalidad de trabajo, la cultura organizacional, el sistema de control y supervisión laborales basadas en la desconfianza, no facilitan la implantación del TT en España al ritmo en el que se impone en otros países de nuestro entorno como Reino Unido, Alemania y Francia, por lo que se hace necesario un cambio de mentalidad colectiva para integrar el TT como alternativa laboral en el marco de la sociedad actual en la que nos desenvolvemos


The development of TIC contributed to the emergence of Telecommuting (TT) in the middle of the last century, but nowadays only the 13.2% of Spanish companies promote it. The cultural and social differences, added to the difficulties to standardize the available information, make it a challenge to unify criteria for its development. The aim of this bibliographic review is to show the global framework of TT in Spain, the risk factors, impact, benefits and drawbacks, detailing the conditions and occupational safety measures that should accompany the process. In order to obtain the articles, a bibliographic research was realized in the principal biomedical databases. It has been evidenced that some beneficial effects would be the high level of autonomy, higher labor satisfaction, better relationship with the supervisor, decreasing of work dropout rate and family conflict. Other publications indicate that strengthening the personal resources, improve the commitment and efficiency of workers. It should be emphasized that the low existence of specific DeCs-MeSH descriptors for TT included in the bibliographical databases using these thesauros as search engine, Medline, Cochrane Library and IBECS, which makes very difficult the recovery of information. The general lack of knowledge about this type of work, the organizational culture, the control and labour supervision system based on mistrust, do not facilitate the implementation of the TT in Spain at the same place as other neighboring countries such as UK, Germany and France impose, this is why it becomes necessary a change of collective mentality to integrate the TT as an alternative employment within the society in which we live


Subject(s)
Humans , Information Technology , Workplace , Organizational Culture , Organizational Innovation , Social Change
8.
Physiol Plant ; 149(1): 45-55, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23189943

ABSTRACT

The effects of varying intensities of light on plants depend on when they occur, even if the total amount of light received is kept constant. We designed an experiment using two clones of robusta coffee (Coffea canephora) intercropped with shelter trees in such a way that allowed us to compare coffee bushes shaded in the morning (SM) with those shaded in the afternoon (SA), and then confronting both with bushes receiving full sunlight over the course of the day (FS). The SM bushes displayed better gas-exchange performance than their SA and FS counterparts, in which the capacity for CO2 fixation was mainly constrained by stomatal (SA bushes) and biochemical (FS bushes) factors. Physiological traits associated with light capture were more responsive to temporal fluctuations of light rather than to the amount of light received, although this behavior could be a clone-specific response. The activity of key antioxidant enzymes differed minimally when comparing the SM and SA clones, but was much larger in FS clones. No signs of photoinhibition or cell damage were found regardless of the light treatments. Acclimations to varying light supplies had no apparent additional cost for constructing and maintaining the leaves regardless of the light supply. Both the SM and SA individuals displayed higher return in terms of revenue streams (e.g. higher mass-based light-saturated photosynthetic rates, photosynthetic nitrogen use efficiencies and long-term water use efficiencies) than their FS counterparts. In conclusion, shading may improve the physiological performance of coffee bushes growing in harsh, tropical environments.


Subject(s)
Coffea/physiology , Plant Leaves/physiology , Acclimatization , Antioxidants/metabolism , Brazil , Carbon Dioxide/metabolism , Chlorophyll/metabolism , Enzymes/metabolism , Light , Photosynthesis/physiology , Plant Stomata/metabolism , Sunlight
9.
Acta biol. colomb ; 17(2): 365-380, mayo-ago. 2012. ilus, graf, tab
Article in Spanish | LILACS | ID: lil-659291

ABSTRACT

La plasticidad fenotípica (PF) es un mecanismo mediante el cual las plantas pueden responder a la heterogeneidad ambiental con ajustes morfológicos y fisiológicos. En este estudio se cuantificó la PF de plantas de Lippia dulcis en respuesta a la disponibilidad hídrica en el suelo (baja, moderada y alta), en caracteres morfológicos y de asignación de biomasa, durante la ontogenia vegetativa (días 39, 45, 59 y 66). Nuestra hipótesis planteó que como respuesta a la disponibilidad hídrica, debería esperarse una mayor PF en caracteres morfológicos en comparación con caracteres de asignación de biomasa. La fracción de masa foliar, la razón del área foliar, la longitud de ramas, el número de hojas, así como la razón biomasa de la raíz/biomasa foliar, presentaron la mayor capacidad de ajuste plástico en las plantas de L. dulcis al déficit hídrico, mientras que el área foliar especifica representó el carácter con menor PF a lo largo de la ontogenia vegetativa. La magnitud y patrón de la PF variaron dependiendo del carácter, agua disponible y desarrollo ontogénico. Contrario a nuestra hipótesis, el grupo de caracteres morfológicos y de asignación de biomasa; exhibieron una PF equivalente. Los modelos de asignación óptima y forrajeo óptimo no son mutuamente excluyentes bajo condiciones de déficit hídrico. L. dulcis alteró su patrón de asignación de biomasa, la morfología foliar y la radicular, y como beneficio adaptativo optimizó el balance entre los órganos encargados de la absorción y el uso de agua. L. dulcis exhibió una notable capacidad para evadir el déficit hídrico.


Phenotypic plasticity (FP) is one of the mechanisms by which plants can respond to environmental heterogeneity by adjusting their morphology and physiology. This study tested and quantified the FP of Lippia dulcis plants in response to water availability in soil (low, medium and high), on morphologic and biomass allocation traits during the vegetative ontogeny (days 39, 45, 59 and 66). We hypothesized that in response to water availability, a higher FP should be expected in morphological compared to biomass allocation traits. The leaf mass fraction, leaf area ratio, branch length, number of leaves and root mass/leaf mass ratio, showed the largest capacity of plastic adjustment in the L. dulcis plants to water deficit, whereas the specific leaf area represented the trait with the lowest FP along vegetative ontogeny. The magnitude and pattern of FP changed depending on trait, water availability and ontogenic development. Contrary to our hypothesis the morphological traits and biomass allocation traits showed equivalent FP. The models of optimum allocation and optimum foraging are not mutually exclusive under water deficit. L. dulcis changed its pattern of biomass allocation, leaf and root morphology and as an adaptive advantage optimized the balance between organs involved in water acquisition and use. L. dulcis showed a remarkable ability to avoid water deficit.

10.
J Exp Bot ; 63(8): 3071-82, 2012 May.
Article in English | MEDLINE | ID: mdl-22378951

ABSTRACT

In this study, the combined effects of light and water availability on the functional relationships of the relative growth rate (RGR), leaf chemical composition, construction and maintenance costs, and benefits in terms of payback time for Coffea arabica are presented. Coffee plants were grown for 8 months in 100% or 15% full sunlight and then a four-month water shortage was implemented. Plants grown under full sunlight were also transferred to shade and vice versa. Overall, most of the traits assessed were much more responsive to the availability of light than to the water supply. Larger construction costs (12%), primarily associated with elevated phenol and alkaloid pools, were found under full sunlight. There was a positive correlation between these compounds and the RGR, the mass-based net carbon assimilation rate and the carbon isotope composition ratio, which, in turn, correlated negatively with the specific leaf area. The payback time was remarkably lower in the sun than in shade leaves and increased greatly in water-deprived plants. The differences in maintenance costs among the treatments were narrow, with no significant impact on the RGR, and there was no apparent trade-off in resource allocation between growth and defence. The current irradiance during leaf bud formation affected both the specific leaf area and leaf physiology upon transferring the plants from low to high light and vice versa. In summary, sun-grown plants fixed more carbon for growth and secondary metabolism, with the net effect of an increased RGR.


Subject(s)
Coffea/growth & development , Coffea/radiation effects , Light , Plant Leaves/chemistry , Plant Leaves/growth & development , Water/physiology , Analysis of Variance , Biomass , Carbon/metabolism , Coffea/metabolism , Plant Leaves/radiation effects , Principal Component Analysis
11.
Rev. Fac. Cienc. Vet ; 52(2): 99-108, dic. 2011. ilus, graf
Article in Spanish | LILACS | ID: lil-631503

ABSTRACT

Con el objetivo de evaluar la vida productiva de cerdas de las razas Large White (LW), Landrace (LR) y sus cruces recíprocos, se analizaron 2444 registros de prolificidad (TAN) y peso acumulado de la camada al nacer (PAN). Los registros de las cerdas provinieron de una granja comercial ubicada en el estado Yaracuy. Los datos fueron ajustados por mes, período de años y número de parto. Para el análisis final se agruparon los años de nacimiento de las cerdas en dos períodos: 1986 - 1998 y 1999 - 2005. Se consideraron las cerdas con la oportunidad de tener al menos tres partos. Se realizaron análisis de varianza por el procedimiento de máxima verosimilitud restringida. Los efectos incluidos en el análisis fueron: grupo racial de cerda (GRC: 1,…,4), período de nacimiento de la cerda (PN: 1, 2), mes de nacimiento de la cerda (MN: 1,…, 12), GRC*MN y la edad al primer parto como covariable. Se obtuvieron promedios ajustados y no ajustados de 39,27 y 39,3 lechones; y 59,5 kg y 59,58 kg para TAN y PAN, respectivamente. Las cerdas del grupo racial LR*LW (42,69 lechones y 63,32 kg) y LW (41,44 lechones y 62,57 kg) resultaron superiores (P<0,01) en TAN y PAN, respectivamente. Hubo efecto estadístico significativo de PN, MN y GRC*MN. La heterosis fue significativa para (TAN) con un valor de 5,9%. Se concluye que las cerdas puras o cruzadas cuyo genotipo posee alelos provenientes de madres de la raza LW, son superiores para los caracteres evaluados.


With the purpose of evaluating the productive life of Large White (LW) and Landrace (LR) sows and their reciprocal crosses, 2.444 records of prolificacy (TAN) and aggregated weight of the litter at birth (PAN) were analyzed. The sow records came from a commercial farm located in the State of Yaracuy, Venezuela. The data were adjusted by month, period of year, and farrowing number. For the final analysis, the years of birth of the sows were grouped into two periods: 1986- 1998 and 1999-2005. Sows with a chance of at least delivering three farrowings were considered. An analysis of variance (ANOVA) by the restricted maximum likelihood procedure was performed. The effects included in the analysis were: breed group of the sow (GRC: 1… 4), birth period of the sow (PN: 1, 2), month of birth of the sow (MN: 1 …12), the GRC*MN interaction, and the age at first farrowing as covariate. The adjusted and non-adjusted TAN averages obtained were 39.27 and 39.3, respectively; and the adjusted and nonadjusted PAN averages were 59.5 and 59.58 kg, in that order. The sows of LR*LW (42.69 piglets and 63.32 kg) and LW (41.44 piglets and 62.57 kg) breed group were higher (P<0.01) in TAN and PAN, respectively. There was a statistically significant effect of PN, PM, and GRC*MN. Heterosis was significant for TAN, with a value of 5.9%. It is concluded that purebred sows and their crosses whose genotype have alleles from mothers of the LW breed, are superior for the characteristics assessed in this research.

12.
Acta biol. colomb ; 15(1): 105-114, abr. 2010.
Article in Spanish | LILACS | ID: lil-634956

ABSTRACT

Los hongos micorrízicos arbusculares (HMA) facilitan la absorción de nutrientes a las plantas hospederas, por esta razón estos microorganismos cumplen un rol fundamental en el funcionamiento de los agroecosistemas. El objetivo de este trabajo fue evaluar el efecto de la asociación simbiótica entre HMA nativos y comerciales y plántulas de Elaeis guineensis en condiciones de vivero con un nivel alto de fósforo (P) en el suelo. Plantas de tres meses de edad fueron sometidas a cuatro tratamientos: Inóculo Nativo (IN), Inóculo Comercial (IC), Mixto (M) y Testigo absoluto (TA). Se evaluaron los parámetros: peso seco total de la planta, peso seco raíz, peso seco parte aérea de la planta, altura de la planta, tasa de crecimiento relativo, colonización micorrízica y número de esporas en el suelo. Se realizaron tres muestreos, uno inicial (día 0), uno a los 45 y a los 90 días después del trasplante de las plántulas (ddt). Los datos fueron analizados mediante un ANOVA o Kruskall-Wallis según el comportamiento de los datos, seguido de un test de Duncan para comparar las medias o un test modificado de Tuckey para datos no paramétricos. Se observaron diferencias significativas en el número de esporas entre los tratamientos IN, M y TA, a los 45 ddt. Para la variable colonización micorrízica se observaron diferencias significativas a los 45 ddt entre los tratamientos IC y TA, mientras que a los 90 ddt se presentaron diferencias entre los tratamientos IN, IC y M, con respecto al TA. A pesar de que el nivel de P en el suelo fue alto, el porcentaje de colonización micorrízica estuvo por encima del 50% en los muestreos realizados a los 45 y 90 días. El tratamiento IN funcionó mejor que los tratamientos IC y M, para las condiciones edáficas de este experimento.


The arbuscular mycorrhizal fungi (AMF) facilitate the absorption of nutrients to the host plants. These microorganisms therefore, fulfill a fundamental roll in the operation of agroecosytems. The aim of this work was to evaluate the effect between native and commercial arbuscular mycorrhizal fungi and Elaeis guineensis seedlings in greenhouse conditions with high P level. Plants of three months of the age were put under four treatments: Native inoculate (NI), Foreign inoculate (FI), Mixture (M) and control (TA). It was evaluated total dry weight of the plant, root and aerial part dry weight, height of the plant, relative growth rate (RGR), mycorrhizal colonization and spores number. At 45 and 90 days after the transplant these variable were evaluated. An initial sampling dry mass was taking by to determine RGR. The data were analyzed through the ANOVA or Kruskall-Wallis according to the behavior of the data, followed of a test of averages of Duncan or a modified test of Tuckey for nonparametric data. Significant differences in the spores number between the treatments NI, FI, M and TA and between NI and M to the 45 days appeared. In the colonization mycorrhizal differences between the treatments FA and TA were observed the 45 days. To the 90 days between all the treatments with respect to the TA. Although the P level in the soil was high, also it was it the mycorrhizal colonization at the two evaluated times. Through time the treatment NI worked better in the soil edaphic conditions used in this experiment.

13.
Acta biol. colomb ; 13(3): 131-146, Dec. 2008.
Article in Spanish | LILACS | ID: lil-634881

ABSTRACT

La capacidad de un genotipo particular de producir diferentes fenotipos es conocido como plasticidad fenotípica (PF). Este trabajo evaluó la PF a través de la ontogenia vegetativa en dos especies de la familia Verbenaceae, Lippia alba ampliamente distribuida en habitats favorables y Lippia origanoides ampliamente distribuida en habitats con bajo disponibilidad de recursos. Se evaluó si la PF está correlacionada con distribución ecologica, en respuesta al contenido relativo de agua en el suelo. Se distribuyeron aleatoriamente 40 clones por tratamiento en tres condiciones experimentales que variaron en la disponibilidad de agua en el suelo, evaluándose distintos caracteres morfológicos y de asignación de biomasa. Los resultados demuestran una falta de asociación entre PF y distribución ecología de ambas especies. Se observó una mayor PF en L. alba en la etapa temprana de la ontogenia vegetativa, demostrando que la PF a través de la ontogenia vegetativa no se presenta de forma uniforme, la amplia distribución ecológica de esta especie se explica por una mayor PF y asignación de biomasa en los diferentes componentes de la tasa de crecimiento relativa (RGR), ya que estos pueden ser ventajosos para alcanzar una rápida madurez sexual y colonizar nuevos hábitats con condiciones favorables. Contrario a nuestra hipótesis, L. origanoides presentó una mayor PF durante la ontogenia vegetativa, los resultados demuestran una posible estrategia de tolerancia al estrés que le permite un bajo desempeño en el RGR en habitats con baja disponibilidad de recursos.


The capacity of genotype to produced different phenotypes is denominated Phenotypic Plasticity (PP). The present study evaluates the PP during the vegetative ontogeny in two species of the family Verbenaceae, Lippia alba which occurs in favorable habitats and L. origanoides which occurs in unfavorable habitats. We compare the PP and its ecological distribution, in response to availability of water in the soil. Forty plants were distributed randomly into three different treatments which had different availabilities of water in the soil. The results indicate a poor association between the PP and the ecological breadth. L. alba presents a high PP in the early stage of the ontogeny demonstrating that it does not exist uniformity in the PP through the vegetative ontogeny, the wide ecological distribution in this specie is explained for a higher allocation of mass in the component the relative growth rate RGR, because this might be an advantage for reaching sexual maturity faster and colonized new favorable habitats. Contrary to our hypothesis of work L. origanoides shows a PP, during the vegetative ontogeny and probably are associated to some mechanisms of tolerance to stress that allow a lower rate in the RGR in unfavorable habitats.

14.
Acta biol. colomb ; 13(1): 53-64, ene.-abr. 2008.
Article in Spanish | LILACS | ID: lil-634995

ABSTRACT

Este trabajo comparó la plasticidad fenotípica (PF) a través de la etapa vegetativa de dos especies del genero Lippia (Verbenaceae) que presentan amplitud ecológica contrastante con respecto a la disponibilidad de nitrógeno. Lippia alba, especie distribuida en suelos de alta a baja disponibilidad de nitrógeno y Lippia origanoides distribuida en suelos con baja disponibilidad de nitrógeno. Nuestra hipótesis de trabajo planteó que la magnitud de la plasticidad fenotípica en estas especies podría correlacionarse con su amplitud ecológica. Treinta y cinco clones de Lippia alba y Lippia origanoides fueron asignado aleatoriamente en tres tratamientos que variaron en la disponibilidad de nitrógeno en el suelo así: 0,5; 2,5 y 5 mM. A los 25, 35, 50 y 70 días cinco clones de cada especie por tratamiento fueron colectadas. Se evaluó el numero de hojas, área foliar, fracción masa de las hojas, fracción masa de la raíz, razón raíz/parte aérea, volumen de la raíz, longitud de la raíz, masa seca total y tasa de crecimiento relativo. Los resultados indican que ambas plantas presentan una alta PF a la disponibilidad de nitrógeno; sin embargo, las normas de reacción de los caracteres estimados variaron dependiendo de la especie y la edad de la planta. Contrario a nuestra hipótesis no encontramos una correlación entre la PF y la distribución ecológica de estas especies.


Here we present a comparative study of phenotypic plasticity in response to soil nitrogen availability in two perennial Lippia species that show different ecological breadth. Lippia alba occurs in soils whith low to high nitrogen concentrations, while Lippia origanoides is only found in soils whit low nitrogen concentrations. We hypothesized that the magnitude of phenotypic plasticity of these species could be correlated with their ecological breadth. Thirty five clones of L. alba and L. origanoides were putted randomly in three treatments with different nitrogen concentrations: 0.5, 2.5 and 5 mM. At 25, 35, 50 and 70 days five plants per treatment was harvested and the number of leaves, leaf area, leaf mass fraction, root mass fraction, root shoot, radical volume, root length, total mass and relative growth rate were evaluated. The results showed that both plants displayed high amounts of phenotypic plasticity in response to nitrogen availability. The reaction norms changed depending of the species and plant age. Contrary to our hypothesis we did not found a correlation between magnitude of phenotypic plasticity and ecological breath.

15.
Acta biol. colomb ; 12(supl.1): 91-102, dic. 2007.
Article in Spanish | LILACS | ID: lil-634862

ABSTRACT

La distribución de la especies es usualmente relacionada con la magnitud de la plasticidad fenotípica (PF). Con el fin de examinar la posible relación entre la magnitud de la PF y la amplitud ecológica en respuesta a la disponibilidad de luz, este trabajo evaluó la PF a través de la ontogenia en clones de Lippia alba y Lippia origanoides, especies congenéricas que presentan diferencias en su distribución. Clones de cada especie fueron distribuidos aleatoriamente en tres tratamientos, baja (33%), media (53%), y alta (100%) disponibilidad lumínica. Se evaluó la PF de caracteres morfológicos y de asignación de biomasa a través de la ontogenia por medio de un análisis de varianza (ANAVA) y la comparación interespecífica se realizó a través del índice de plasticidad fenotípica (RDPI). L. alba y L. origanoides presentaron variación de la plasticidad a través de la ontogenia en varios de los caracteres estudiados. La comparación interespecífica a través del RDPI mostró que la mayor PF de L. alba sobre L. origanoides en algún estado de la ontogenia no fue consistente ni uniforme a través de esta. Estos resultados sugieren una débil asociación entre la magnitud de la PF en respuesta a la disponibilidad lumínica. Además, indican que la mayor distribución de L. alba, se debe a un mayor desempeño en la tasa de crecimiento relativa y consecuentemente a una mayor acumulación de biomasa total, que posiblemente, le permiten alcanzar rápidamente su madurez sexual y así la colonización de nuevas áreas.


The distribution of the plant species is usually related to the magnitude of the phenotypic plasticity (PF). With the purpose of to stablish the possible relationship between the magnitude of the PF and the ecological breadth in response to light availability, the PF during the ontogeny in clones of Lippia alba and Lippia origanoides was evaluated. Both species are congeneris and show differences in their distribution. Three random treatments of light availability were set up, low (33%), medium (53%), and high (100%). The PF of morphologic and biomass allocation traits was evaluated during the ontogeny in clones of L. alba and L. origanoides through the ANOVA and the interspecific comparison were carried out through relative distance plasticity index (RDPI). L. alba and L. origanoides displayed variation of the plasticity through the ontogeny in several of the studied traits. The interspecific comparison through RDPI showed that the PF greather of L. alba in comparison to L. origanoides in some state of the ontogeny was not consistent nor uniform. These results suggest a lack association between the magnitudes of the PF in response to the availability of light. Additionally this indicate that the greater distribution of L. alba could be cause by a greater performance in the relative rate of growth and the greater accumulation of total biomass, therefore, it would likely contribute L. alba to reach its sexual maturity faster and the colonization of new areas.

16.
Acta biol. colomb ; 11(supl.1): 75-87, dic. 2006. graf
Article in Spanish | LILACS | ID: lil-469076

ABSTRACT

Cómo responden las plantas a la variabilidad en la disponibilidad de los recursos abióticos, es un tema central en estudios de fisiología ecológica. Varios modelos de partición óptima han sugerido un balance funcional en la biomasa asignada al vástago y la raíz con la siguiente predicción: “las plantas cambiarían su asignación de biomasa hacia el vástago si la ganancia de carbono de la parte aérea de la planta es afectada por un nivel bajo de recursos sobre el suelo, tal como luz o CO2. Igualmente, las plantas cambiarían su asignación hacia la raíz si el nivel de los recursos del suelo es bajo, tal como nutrientes y agua”. Estos cambios en la asignación pueden ser considerados como adaptativos, ya que permiten a la planta capturar más de aquel recurso que limita fuertemente su crecimiento. En este trabajo, discutimos algunos esquemas metodológicos que a través de la descripción y análisis de la asignación de biomasa pretenden probar dicha predicción. Enfatizamos que la conclusión extraída en contra o a favor de la predicción se fundamenta en la interpretación del término plasticidad, conllevando recientemente al uso de metodologías que sugieren que la predicción no se cumple en respuesta a la disponibilidad de algunos recursos. Proponemos la utilización de un protocolo de investigación para estudiar los patrones de asignación de biomasa y sugerimos una metodología para cuantificar la plasticidad de diferentes genotipos desde un punto de vista discreto.


Subject(s)
Biomass , Plants/growth & development
17.
Genetics ; 169(4): 1873-82, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15687271

ABSTRACT

The essential Hsp40, Sis1, is a J-protein cochaperone for the Ssa class of Hsp70's of Saccharomyces cerevisiae. Sis1 is required for the maintenance of the prion [RNQ(+)], as Sis1 lacking its 55-amino-acid glycine-rich region (G/F) does not maintain [RNQ(+)]. We report that overexpression of Sis1DeltaG/F in an otherwise wild-type strain had a negative effect on both cell growth and [RNQ(+)] maintenance, while overexpression of wild-type Sis1 did not. Overexpression of the related Hsp40 Ydj1 lacking its G/F region did not cause inhibition of growth, indicating that this dominant effect of Sis1DeltaG/F is not a characteristic shared by all Hsp40's. Analysis of small deletions within the SIS1 G/F region indicated that the observed dominant effects were caused by the absence of sequences known to be important for Sis1's unique cellular functions. These inhibitory effects of Sis1DeltaG/F were obviated by alterations in the N-terminal J-domain of Sis1 that affect interaction with Ssa's ATPase domain. In addition, a genetic screen designed to isolate additional mutations that relieved these inhibitory effects identified two residues in Sis1's carboxy-terminal domain. These alterations disrupted the interaction of Sis1 with the 10-kD carboxy-terminal regulatory domain of Ssa1, indicating that Sis1 has a bipartite interaction with Ssa in vivo.


Subject(s)
Gene Expression Regulation, Fungal , HSP70 Heat-Shock Proteins/physiology , Heat-Shock Proteins/physiology , Saccharomyces cerevisiae Proteins/physiology , Adenosine Triphosphatases/physiology , Amino Acid Sequence , Binding, Competitive , Cell Proliferation , Dose-Response Relationship, Drug , Enzyme-Linked Immunosorbent Assay , Fungal Proteins/chemistry , Gene Deletion , Gene Library , Genes, Fungal , Genetic Techniques , Green Fluorescent Proteins/metabolism , HSP40 Heat-Shock Proteins , Immunoblotting , Luciferases/metabolism , Molecular Sequence Data , Mutation , Plasmids/metabolism , Prions/metabolism , Protein Binding , Protein Conformation , Protein Structure, Secondary , Protein Structure, Tertiary , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae Proteins/chemistry , Substrate Specificity , Temperature , Time Factors
19.
Rev. cuba. med. gen. integr ; 20(2)mar.-abr. 2004. tab, graf
Article in Spanish | CUMED | ID: cum-24617

ABSTRACT

Se elaboró la "Guía práctica para la prescripción fitoterapéutica en la atención primaria de salud", teniendo en cuenta la necesidad de garantizar una prescripción adecuada de fitofármacos en ese nivel de atención. Se realizó, partiendo de las relaciones existentes entre las acciones farmacológicas valoradas experimentalmente, y las formas farmacéuticas de las plantas medicinales aprobadas por el MINSAP. Esta relación quedó establecida empleando tablas de doble entrada y utilizando el sistema de coordenadas, lo cual permite una rápida definición de la prescripción; y de igual forma, se pueden establecer las vías de administración, la posología, las contraindicaciones y las advertencias. Otros datos sobre las plantas medicinales y sus principios activos se ofrecen al facultativo para el conocimiento integral de los fitofármacos a los cuales dan origen(AU)


Subject(s)
Plants, Medicinal , Plant Extracts/therapeutic use , Plant Extracts/pharmacology , Phytotherapy , Primary Health Care , Drug Prescriptions
20.
Rev. cuba. med. gen. integr ; 20(2)mar.-abr. 2004. tab, graf
Article in Spanish | LILACS | ID: lil-400257

ABSTRACT

Se elaboró la "Guía práctica para la prescripción fitoterapéutica en la atención primaria de salud", teniendo en cuenta la necesidad de garantizar una prescripción adecuada de fitofármacos en ese nivel de atención. Se realizó, partiendo de las relaciones existentes entre las acciones farmacológicas valoradas experimentalmente, y las formas farmacéuticas de las plantas medicinales aprobadas por el MINSAP. Esta relación quedó establecida empleando tablas de doble entrada y utilizando el sistema de coordenadas, lo cual permite una rápida definición de la prescripción; y de igual forma, se pueden establecer las vías de administración, la posología, las contraindicaciones y las advertencias. Otros datos sobre las plantas medicinales y sus principios activos se ofrecen al facultativo para el conocimiento integral de los fitofármacos a los cuales dan origen


Subject(s)
Phytotherapy , Plant Extracts , Plants, Medicinal , Drug Prescriptions , Primary Health Care
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