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1.
Brain Commun ; 6(2): fcae057, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38495303

RESUMO

Cerebral small vessel disease is a major contributor to both brain aging and cognitive decline. This study aimed to determine the prevalence of cerebral small vessel disease in a Colombian population over 40 years of age who attended a Radiology and Diagnostic Imaging service for brain MRI between October 2018 and March 2019. This was an observational, cross-sectional and analytical study of 710 adult patients over 40 years of age who attended the Radiology and Diagnostic Imaging service for a brain MRI. The analysed data were obtained from an anonymized database of the service. We studied 710 MRI scans of patients aged between 40 and 104 years. The most frequent risk factor was hypertension (36.2%). Brain abnormalities associated with cerebral small vessel disease, such as white matter hyperintensities, were seen in 56.20% of the population, and brain atrophy was observed in 12.96%. Brain disease prevalence increased with age (23.18% for those aged 55 years, 54.49% for those aged 55-64 years, 69.8% for those aged 65-74 years and 90.53% for those older than 75 years). The prevalence of cerebral small vessel disease in our population was similar to that reported in the world literature, as were the prevalence of the evaluated cardiovascular risk factors. Additionally, we identified an association between hypertension and advanced age with cerebral small vessel disease, with white matter hyperintensities being the most characteristic finding.

2.
Horiz. med. (Impresa) ; 23(3)jul. 2023.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1514220

RESUMO

Objetivo: Determinar la prevalencia y los factores asociados con el trastorno depresivo en adultos peruanos mayores de 60 años. Materiales y métodos: Se realizó un estudio observacional, analítico y transversal a partir de un análisis secundario de la Encuesta Demográfica y de Salud Familiar (ENDES) del año 2019, aplicada con un alcance nacional por el Instituto Nacional de Estadística e Informática del Perú (INEI). La muestra fue de 4174 adultos mayores. Se consideró como variable principal el padecer de trastorno depresivo (con depresión/sin depresión) y como variables independientes, edad, sexo, grado de instrucción, quintil de riqueza (clasificado en cinco niveles de riqueza), área de residencia (clasificada como urbano y rural), dominio geográfico (clasificado como Lima Metropolitana, resto de la Costa, Sierra y Selva), cobertura de salud (clasificada como sin cobertura y con cobertura), consumo de alcohol (sí/no), hábito de fumar (sí/no) y presencia de discapacidad (sí/no). Se realizaron análisis de frecuencias absolutas y relativas, diferencias de proporciones y un análisis multivariado mediante modelos lineales generalizados. Resultados: La prevalencia del trastorno depresivo fue del 13,18 % y de la discapacidad, 7,86 %. Los adultos mayores de sexo masculino tuvieron menos probabilidades de padecer trastorno depresivo (RPa = 0,602; IC 95 %: 0,513-0,706) que las mujeres, así como los integrantes del grupo etario de mayores de 85 años presentaron mayor riesgo que los de 60 a 74 (RPa = 1,664; IC 95 %: 1,304-2,124). Además, el no padecer de alguna discapacidad se comportó como un factor preventivo (RPa = 0,542; IC 95 %: 0,440-0,668), mientras que un mayor grado de instrucción y quintil de riqueza, desde el quintil "medio", indicaron también ser factores de protección al tomarse como referencia las categorías "sin educación" y "los más pobres", respectivamente (p < 0,005). Conclusiones: El pertenecer al grupo de mayores de 85 años, del sexo femenino, de bajos quintiles de riqueza, padecer de alguna discapacidad y tener un menor grado de instrucción constituyen factores de riesgo para el trastorno depresivo en adultos mayores peruanos.


Objective: To determine the prevalence and factors associated with depressive disorder among Peruvian older adults over 60 years of age. Materials and methods: An observational, analytical and cross-sectional study was conducted based on a secondary analysis of the 2019 Encuesta Demográfica y de Salud Familiar (ENDES National Demographic and Family Health Survey), administered at national level by Instituto Nacional de Estadística e Informática del Perú (INEI National Institute of Statistics and Informatics of Peru). The sample consisted of 4,174 older adults. The main variable was suffering from a depressive disorder (depressed/not depressed) and the independent variables were age, sex, educational level, wealth quintile (classified into five levels of wealth), area of residence (classified as urban/rural), geographic domain (classified as Lima Metropolitan Area, the rest of the coast, the highlands and the jungle), health coverage (classified as insured/uninsured), alcohol consumption (yes/no), smoking (yes/no) and presence of a disability (yes/no). Analyses of absolute and relative frequencies, differences in proportions and a multivariate analysis using generalized linear models (GLM) were performed. Results: The prevalence of depressive disorder and disability accounted for 13.18 % and 7.86 %, respectively. Older males were less likely to suffer from a depressive disorder (PRa = 0.602; 95 % CI: 0.513-0.706) than females, and the group over 85 years of age showed a higher risk than those from 60 to 74 years (PRa = 1.664; 95 % CI: 1.304-2.124). Besides, not presenting a disability behaved as a preventive factor (PRa = 0.542; 95 % CI: 0.440-0.668), while a higher educational level and wealth quintile, starting from the "Middle" quintile, were protective factors when taking the categories "No education" and "The poorest" as reference, respectively (p < 0.005). Conclusions: Belonging to the group over 85 years of age, being a female, being in lower wealth quintiles, suffering from a disability and having a lower educational level were risk factors for depressive disorder among Peruvians older adults.

3.
Acta Crystallogr C Struct Chem ; 79(Pt 1): 3-11, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36602015

RESUMO

Three new styrylquinoline-chalcone hybrids have been synthesized using a three-step pathway starting with Friedländer cyclocondensation between (2-aminophenyl)chalcones and acetone to give 2-methyl-4-styrylquinolines, followed by selective oxidation to the 2-formyl analogues, and finally Claisen-Schmidt condensation between the formyl intermediates and 1-acetylnaphthalene. All intermediates and the final products have been fully characterized by IR and 1H/13C NMR spectroscopy, and by high-resolution mass spectrometry, and the three products have been characterized by single-crystal X-ray diffraction. The molecular conformations of (E)-3-{4-[(E)-2-phenylethenyl]quinolin-2-yl}-1-(naphthalen-1-yl)prop-2-en-1-one, C30H21NO, (IVa), and (E)-3-{4-[(E)-2-(4-fluorophenyl)ethenyl]quinolin-2-yl}-1-(naphthalen-1-yl)prop-2-en-1-one, C30H20FNO, (IVb), are very similar. In each compound, the molecules are linked into a three-dimensional array by hydrogen bonds, of the C-H...O and C-H...N types in (IVa), and of the C-H...O and C-H...π types in (IVb), and by two independent π-π stacking interactions. By contrast, the conformation of the chalcone unit in (E)-3-{4-[(E)-2-(2-chlorophenyl)ethenyl]quinolin-2-yl}-1-(naphthalen-1-yl)prop-2-en-1-one, C30H20ClNO, (IVc), differs from those in (IVa) and (IVb). There are only weak hydrogen bonds in the structure of (IVc), but a single rather weak π-π stacking interaction links the molecules into chains. Comparisons are made with some related structures.


Assuntos
Chalcona , Chalconas , Chalcona/química , Chalconas/química , Cristalografia por Raios X , Ligação de Hidrogênio
4.
J Neurol ; 270(2): 618-631, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35817988

RESUMO

Nowadays, it becomes of paramount societal importance to support many frail-prone groups in our society (elderly, patients with neurodegenerative diseases, etc.) to remain socially and physically active, maintain their quality of life, and avoid their loss of autonomy. Once older people enter the prefrail stage, they are already likely to experience falls whose consequences may accelerate the deterioration of their quality of life (injuries, fear of falling, reduction of physical activity). In that context, detecting frailty and high risk of fall at an early stage is the first line of defense against the detrimental consequences of fall. The second line of defense would be to develop original protocols to detect future fallers before any fall occur. This paper briefly summarizes the current advancements and perspectives that may arise from the combination of affordable and easy-to-use non-wearable systems (force platforms, 3D tracking motion systems), wearable systems (accelerometers, gyroscopes, inertial measurement units-IMUs) with appropriate machine learning analytics, as well as the efforts to address these challenges.


Assuntos
Fragilidade , Qualidade de Vida , Humanos , Idoso , Medo , Aprendizado de Máquina
5.
Acta Crystallogr C Struct Chem ; 78(Pt 10): 524-530, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36196785

RESUMO

Three new 2-methyl-4-styrylquinoline derivatives have been synthesized in high yields using Friedländer reactions between chalcones [1-(2-aminophenyl)-3-arylprop-2-en-1-ones] and acetone, and characterized using IR, 1H and 13C NMR spectroscopy, and mass spectrometry, and by crystal structure analysis. In (E)-4-(4-fluorostyryl)-2-methylquinoline, C18H14FN, (I), the molecules are joined into cyclic centrosymmetric dimers by C-H...N hydrogen bonds and these dimers are linked into sheets by π-π stacking interactions. The molecules of (E)-2-methyl-4-[4-(trifluoromethyl)styryl]quinoline, C19H14F3N, (II), are linked into cyclic centrosymmetric dimers by C-H...π hydrogen bonds and these dimers are linked into chains by a single π-π stacking interaction. There are no significant hydrogen bonds in the structure of (E)-4-(2,6-dichlorostyryl)-2-methylquinoline, C18H13Cl2N, (III), but molecules related by translation along [010] form stacks with an intermolecular spacing of only 3.8628 (2) Å. Comparisons are made with the structures of some related compounds.


Assuntos
Chalcona , Chalconas , Quinolinas , Acetona , Cristalografia por Raios X , Ligação de Hidrogênio , Estrutura Molecular , Quinolinas/química
7.
Rev. colomb. cienc. pecu ; 35(1)mar. 2022.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1535780

RESUMO

Background: Commensal microflora such as Escherichia coli and Enterococcus spp. are representative indicators of antimicrobial resistance (AMR) as they are part of the normal intestinal microflora and can acquire and disseminate AMR to pathogenic or zoonotic bacteria like Salmonella spp. Objective: To investigate the state of AMR among E. coli and Salmonella spp., potential pathogens in humans, isolated from cecal contents of pigs submitted to a veterinary diagnostic laboratory in Colombia from 2016 to 2019. Methods: Susceptibility testing was conducted using the Kirby-Bauer disk diffusion method according to the Clinical and Laboratory Standards Institute guidelines for antimicrobial zone diameter breakpoints. An E. coli strain (ATCC 25922) was used as the quality control organism. Isolates showing resistance to three or more antimicrobial classes were classified as multidrug-resistant (MDR) as defined by a joint group of the European Centre for Disease prevention and Control and the Center for Disease Control and Prevention of the USA. Results: A total of 112 E. coli and 192 Salmonella spp. colonies were isolated from 557 samples received between 2016 and 2019. In order of decreasing frequency, E. coli was resistant to tetracycline (100%), sulfamethoxazol-trimethoprim (97.5%), amoxicillin (86.4%), enrofloxacin (82.6%), tylosin (82.1%), doxycycline (59%), neomycin (50%), ciprofloxacin (45.5%), ceftiofur (35%), gentamicin (30%), tilmicosin (29%), and fosfomycin (12.5%). When compared with E. coli, Salmonella spp. was generally resistant to the same agents with slightly less resistance (between 10-30%) to eight of the antimicrobials tested. Salmonella spp. showed <20% resistance to three antimicrobials, as follows: neomycin (17%), gentamicin (16%), and fosfomycin (14%). Multi-resistance occurred in 68.7% (77/112) of E. coli and 70.3% (135/192) of Salmonella spp. isolates. Resistance of Salmonella spp. was alarming to all the critically important antimicrobials tested: fluoroquinolones (enrofloxacin, ciprofloxacin), ceftiofur (third- generation cephalosporin), and macrolides (tylosin). Conclusions: According to our results, there is a high level of multi- drug resistance (MDR) in E. coli and Salmonella spp. It is necessary to implement a nationwide antimicrobial resistance monitoring program in Colombia, together with proper antimicrobial prescribing guidelines for pigs. The indiscriminate use of antimicrobial growth promoters by the swine industry is generating widespread bacterial resistance and should be discontinued.


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Antecedentes: Flora comensal como espécies de Escherichia coli e Enterococcus são tipicamente escolhidas como indicadores representativos de la resistência antimicrobiana (AMR), pois fazem parte da flora intestinal normal e podem adquirir e disseminar AMR a bactérias patogênicas ou zoonóticas como Salmonella spp. Objetivo: Investigar o estado da AMR entre E. coli e Salmonella spp. isolados do conteúdo cecal de porcos colombianos submetidos ao Laboratório de Diagnóstico Veterinário de 2016 a 2019, ambos sendo patógenos potenciais em humanos. Métodos: O teste de suscetibilidade foi conduzido usando o método de difusão em disco Kirby-Bauer de acordo com as diretrizes do Instituto de Padrões Clínicos e Laboratoriais para pontos de quebra de diâmetro da zona antimicrobiana. A cepa de E. coli (ATCC 25922) foi usada como organismo de controle de qualidade. Os isolados que apresentam resistência a três ou mais classes de antimicrobianos foram classificados como multirresistentes (MDR), conforme definido por um grupo conjunto do Centro Europeu para Prevenção e Controle de Doenças e Centro para Controle e Prevenção de Doenças dos EUA. Resultados: Um total de 112 E. coli e 192 Salmonella spp. foram isolados de 557 amostras submetidas entre 2016 e 2019. Em ordem decrescente de frequência, a resistência a E. coli foi: tetraciclina (100%), sulfametoxazol-trimetoprim (97,5%), amoxicilina (86,4%), enrofloxacina (82,6%), tilosina (82,1%), doxiciclina (59%), neomicina (50%), ciprofloxacina (45,5%), ceftiofur (35%), gentamicina (30%), tilmicosina (29%) e fosfomicina (12,5%). Quando comparada com E. coli, Salmonella spp. foi geralmente resistente aos mesmos agentes com resistência ligeiramente menor (entre 10-30%) a oito dos antimicrobianos. Apenas três antimicrobianos apresentaram resistência a Salmonella spp. abaixo de 20% da seguinte forma: neomicina (17%), gentamicina (16%) e fosfomicina (14%). Multi-resistência ocorreu em 68,7% (77/112) de E. coli e 70,3% (135/192) de Salmonella spp. isolados. Resistência de Salmonella spp. foi alarmante para todos os antimicrobianos criticamente importantes testados: fluoroquinolonas (enrofloxacina, ciprofloxacina), ceftiofur (cefalosporina de terceira geração) e macrolídeos (tilosina). Conclusões: Esses resultados indicam um alto nível de resistência a múltiplos medicamentos (MDR) e que um Programa Nacional de Monitoramento da Resistência Antimicrobiana é necessário para a Colômbia, juntamente com a implementação de diretrizes de prescrição de antimicrobianos para suínos. O uso indiscriminado de antimicrobianos para promoção de crescimento na indústria suína está claramente promovendo resistência generalizada e deve ser interrompido.

8.
Aging Med (Milton) ; 3(3): 188-194, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33103039

RESUMO

The increasing number of frail elderly people in our aging society is becoming problematic: about 11% of community-dwelling older persons are frail and another 42% are pre-frail. Consequently, a major challenge in the coming years will be to test people over the age of 60 years to detect pre-frailty at the earliest stage and to return them to robustness using the targeted interventions that are becoming increasingly available. This challenge requires individual longitudinal monitoring (ILM) or follow-up of community-dwelling older persons using quantitative approaches. This paper briefly describes an effort to tackle this challenge. Extending the detection of the pre-frail stages to other population groups is also suggested. Appropriate algorithms have been used to begin the tracing of faint physiological signals in order to detect transitions from robustness to pre-frailty states and from pre-frailty to frailty states. It is hoped that these studies will allow older adults to receive preventive treatment at the correct institutions and by the appropriate professionals as early as possible, which will prevent loss of autonomy. Altogether, ILM is conceived as an emerging property of databases ("digital twins") and not the reverse. Furthermore, ILM should facilitate a coordinated set of actions by the caregivers, which is a complex challenge in itself. This approach should be gradually extended to all ages, because frailty has no age, as is testified by overwork, burnout, and post-traumatic syndrome.

9.
J Neurophysiol ; 123(6): 2269-2284, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32319842

RESUMO

Humans exhibit various motor styles that reflect their intra- and interindividual variability when implementing sensorimotor transformations. This opens important questions, such as, At what point should they be readjusted to maintain optimal motor control? Do changes in motor style reveal the onset of a pathological process and can these changes help rehabilitation and recovery? To further investigate the concept of motor style, tests were carried out to quantify posture at rest and motor control in 18 healthy subjects under four conditions: walking at three velocities (comfortable walking, walking at 4 km/h, and race walking) and running at maximum velocity. The results suggest that motor control can be conveniently decomposed into a static component (a stable configuration of the head and column with respect to the gravitational vertical) and dynamic components (head, trunk, and limb movements) in humans, as in quadrupeds, and both at rest and during locomotion. These skeletal configurations provide static markers to quantify the motor style of individuals because they exhibit large variability among subjects. Also, using four measurements (jerk, root mean square, sample entropy, and the two-thirds power law), it was shown that the dynamics were variable at both intra- and interindividual levels during locomotion. Variability increased following a head-to -toe gradient. These findings led us to select dynamic markers that could define, together with static markers, the motor style of a subject. Finally, our results support the view that postural and motor control are subserved by different neuronal networks in frontal, sagittal, and transversal planes.NEW & NOTEWORTHY During human locomotion, motor control can be conveniently decomposed into a static and dynamic components. Variable dynamics were observed at both the intra- and interindividual levels during locomotion. Variability increased following a head-to-toe gradient. Finally, our results support the view that postural and motor control are subserved by different neuronal networks in the frontal, sagittal, and transversal planes.


Assuntos
Fenômenos Biomecânicos/fisiologia , Atividade Motora/fisiologia , Rede Nervosa/fisiologia , Corrida/fisiologia , Caminhada/fisiologia , Adulto , Feminino , Humanos , Individualidade , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
Parasitology ; 146(6): 765-773, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30585147

RESUMO

Despite intensive research during the last few decades, understanding of ecological and physiological factors related to haemosporidian infections in birds is still fragmentary. Since more model organisms are needed in order to understand these infections in the wild, we analysed avian haemosporidian infections in the rufous-collared sparrow (Zonotrichia capensis, Emberizidae) in a dry forest of the Ecuadorian Andes. Parasite diversity was screened using molecular and morphological approaches. By molecular diagnosis, we identified three linages that were phylogenetically placed in the context of molecular haemosporidian diversity and associated with a morphospecies. By microscopy, we identified five described morphospecies and one additional undescribed morphospecies. We found that avian haemosporidian prevalence on the study site was 76.3%. Additionally, we used a series of generalized linear models to explore the potential relationship of parasite prevalence and parasitaemia with a set of variables related to physiological and environmental conditions. Although our results revealed associations of haemosporidian infections with precipitation, age and sampling site, the models only explained a small fraction of the variation.

12.
Rev. colomb. psiquiatr ; 47(3): 155-164, jul.-set. 2018. tab
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-978316

RESUMO

RESUMEN Antecedentes: El trastorno conversivo es un reto para los clínicos por los vacíos conceptuales en lo que respecta a la patogenia y cómo confluyen otras entidades psiquiátricas y la falta de aproximaciones a las vivencias tanto de pacientes como de familiares con la enfermedad. Objetivo: Describir los modelos explicativos (ME) que utilizan los cuidadores de niños y adolescentes con trastorno conversivo que consultan al Hospital Pediátrico de La Misericordia. Métodos: Se realizó un estudio cualitativo con una muestra por conveniencia de 10 casos atendidos entre mayo de 2014 y abril de 2015. La herramienta usada fue una entrevista en profundidad con padres y/o cuidadores. Resultados: Los cuidadores tienen diversas creencias en torno al origen de los síntomas, y consideran principalmente enfermedad, factores mágicos místicos y factores psicosociales. Se explican los síntomas en cada caso de varias maneras, y no se encontró una relación directa entre estas creencias, el patrón de síntomas y los comportamientos de búsqueda de ayuda. La presentación sintomática es polimorfa y genera interferencia principalmente en la actividad escolar de los pacientes. La atención médica se percibe como pertinente y la atención psiquiátrica, como insuficiente. Entre los itinerarios terapéuticos, se describen consultas con diversos agentes, además de la atención médica, incluidas medicinas alternativas y enfoques mágico-religiosos. Conclusiones: Los ME en trastorno conversivo son variados, pero incluyen con frecuencia elementos mágico-religiosos y factores psicosociales. Las creencias subyacentes no se relacionan directamente con la búsqueda de ayuda u otras variables.


ABSTRACT Background: Conversion disorder is a challenge for clinicians due to the conceptual gaps as regards its pathogenesis, the way in which it converges with other psychiatric disorders, and the lack of approaches to the experiences of both patients and family members with the disease. Objective: To describe Explanatory Models (EM) offered to caregivers of paediatric patients with conversion disorder who attended the Hospital de la Misericordia. Methods: A qualitative study was conducted with a convenience sample of 10 patients who attended the Hospital de La Misericordia, ¿Bogotá? between May 2014 and April 2015. The tool used was an in-depth interview applied to parents and/or caregivers. Results: Caregivers have different beliefs about the origin of the symptoms, especially considering sickness, magical-mystical factors, and psychosocial factors. The symptoms are explained in each case in various ways and there is no direct relationship between these beliefs, the pattern of symptoms, and help-seeking behaviours. Symptomatic presentation is polymorphous and mainly interferes in the patient's school activities. The medical care is perceived as relevant, and psychiatric care as insufficient. Among the therapeutic routes, consultations with various agents are described, including medical care, alternative medicine, and magical-religious approaches. Conclusions: EMs in conversion disorder are varied, but often include magical-religious elements and psychosocial factors. The underlying beliefs are not directly related to help-seeking behaviours or other variables.


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Adulto , Terapêutica , Cuidadores , Transtorno Conversivo , Psicologia , Encaminhamento e Consulta , Estresse Psicológico , Terapias Complementares , Patogenesia Homeopática , Sistema Médico de Emergência , Cuidados Médicos , Comportamento de Busca de Ajuda , Transtornos Mentais
13.
Rev Colomb Psiquiatr (Engl Ed) ; 47(3): 155-164, 2018.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30017038

RESUMO

BACKGROUND: Conversion disorder is a challenge for clinicians due to the conceptual gaps as regards its pathogenesis, the way in which it converges with other psychiatric disorders, and the lack of approaches to the experiences of both patients and family members with the disease. OBJECTIVE: To describe Explanatory Models (EM) offered to caregivers of paediatric patients with conversion disorder who attended the Hospital de la Misericordia. METHODS: A qualitative study was conducted with a convenience sample of 10 patients who attended the Hospital de La Misericordia, ¿Bogota? between May 2014 and April 2015. The tool used was an in-depth interview applied to parents and/or caregivers. RESULTS: Caregivers have different beliefs about the origin of the symptoms, especially considering sickness, magical-mystical factors, and psychosocial factors. The symptoms are explained in each case in various ways and there is no direct relationship between these beliefs, the pattern of symptoms, and help-seeking behaviours. Symptomatic presentation is polymorphous and mainly interferes in the patient's school activities. The medical care is perceived as relevant, and psychiatric care as insufficient. Among the therapeutic routes, consultations with various agents are described, including medical care, alternative medicine, and magical-religious approaches. CONCLUSIONS: EMs in conversion disorder are varied, but often include magical-religious elements and psychosocial factors. The underlying beliefs are not directly related to help-seeking behaviours or other variables.


Assuntos
Cuidadores/psicologia , Transtorno Conversivo/psicologia , Comportamento de Busca de Ajuda , Modelos Teóricos , Adolescente , Criança , Transtorno Conversivo/terapia , Feminino , Humanos , Entrevistas como Assunto , Masculino
14.
Acta Trop ; 183: 162-172, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29621533

RESUMO

Vector ecology is a key factor in understanding the transmission of disease agents, with each species having an optimal range of environmental requirements. Scarce data, however, are available for how interactions of local and broad-scale climate phenomena, such as seasonality and the El Niño Southern Oscillation (ENSO), affect simuliids. We, therefore, conducted an exploratory study to examine distribution patterns of species of Simuliidae along an elevational gradient of the Otún River in the Colombian Andes, encompassing four ecoregions. Larval and pupal simuliids were sampled at 52 sites ranging from 1800 to 4750 m above sea level in dry and wet seasons and during the La Niña phase (2011-2012) and the El Niño phase (2015-2016) of the ENSO; physicochemical measurements were taken during the El Niño phase. Twenty-seven species in two genera (Gigantodax and Simulium) were collected. Species richness and occurrence in each ecoregion were influenced by elevation, seasonality, and primarily the warm El Niño and cool La Niña phases of the ENSO. The degree of change differed among ecoregions and was related to physicochemical factors, mainly with stream discharge. Some putative simuliid vectors of Leucocytozoon, such as G. misitu and S. muiscorum, markedly changed in distribution and occurrence, potentially influencing parasite transmission.


Assuntos
Distribuição Animal/fisiologia , El Niño Oscilação Sul , Estações do Ano , Simuliidae/crescimento & desenvolvimento , Animais , Colômbia , Ecologia , Rios , Simuliidae/classificação , Especificidade da Espécie
15.
Annu Int Conf IEEE Eng Med Biol Soc ; 2017: 2267-2270, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29060349

RESUMO

In this paper, we present a method for the creation of a library of inertial signals based on Dynamic Time Warping (DTW) for step characterization, with preliminary results in control subjects and patients with neurological diseases. Subjects performed a protocol including a 10 m straight walking, then turn back and walking for additional 10 m. The library is constructed with inertial signals (acceleration and angular velocities recorded in three directions) aligned with the DTW. Templates in the library are obtained for a specific cohort and for the different walking phases of the protocol. They are compared to the signal of a single subject by calculating a Pearson correlation coefficient. The method has been tested on a database of 864 exercises, obtained from 71 healthy controls, 24 patients with Parkinson disease and 48 patients with Radiation Induced Leukoencephalopathy (RIL). Pearson correlation classification reports a precision of about 85% for step detection. For exercise characterization the sensitivity is about 57%, 56% and 82% for Parkinson, RIL and control subjects respectively.


Assuntos
Caminhada , Aceleração , Terapia por Exercício , Humanos , Tempo
16.
Protist ; 167(2): 185-204, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-27016638

RESUMO

Studies of the lowland avifauna in the Neotropical Region have shown a paucity of Leucocytozoon species. However, surveys conducted in the Colombian highlands revealed a great diversity of these parasites infecting resident birds. To further investigate the relationship between Leucocytozoon diversity, the potential vectors, and altitudinal distribution, birds from 41 families were sampled at low and high elevations in Colombia. Blood samples were screened by microscopy, and a fragment of cytochrome b was amplified from Leucocytozoon-positive samples. The complete mitochondrial genome was also obtained for each morphospecies of Leucocytozoon. Leucocytozoon species were detected in resident birds, with various degrees of host specificity, at elevations from 2,400 to 3,950 meters above sea level, where five new host-parasite associations were discovered. Phylogenetic analysis based on the cytochrome b fragment suggested that two nominal taxa, L. fringillinarum and L. majoris, are species complexes. Blood sources of Simuliidae revealed generalist-feeding habits that included avian and mammalian hosts. Molecular analysis of parasites in black flies indicated a close relationship with the parasites found in birds. Our investigation provides further evidence that the distribution and transmission of Leucocytozoon species in the Neotropics are influenced by elevation, with the highest prevalence between 2,400 and 3,200 m asl.


Assuntos
Doenças das Aves/parasitologia , Doenças das Aves/transmissão , Aves/parasitologia , Citocromos b/genética , Genoma Mitocondrial/genética , Haemosporida/classificação , Haemosporida/genética , Animais , Colômbia , Geografia , Especificidade de Hospedeiro , Interações Hospedeiro-Parasita , Mitocôndrias/genética , Simuliidae/parasitologia
17.
Acta Trop ; 159: 83-94, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26995696

RESUMO

The great diversity of birds and ecosystems in the Andean mountains has been understudied in terms of their parasite species. We describe a new Haemoproteus parasite, H. (Parahaemoproteus) erythrogravidus infecting Zonotrichia capensis (Rufous-Collared Sparrow) in South America. The description of this blood parasite species is supported by morphological and molecular data based on a fragment of cytochrome b gene (cyt b) and complete mitochondrial genome sequences. The new species is closely related to H. (Parahaemoproteus) coatneyi, and it can be readily distinguished from the latter parasite due to morphology of its blood stages, particularly 1) the formation of a marked protrusion on envelope of infected erythrocytes by the majority of developing gametocytes, a feature which is unique for this Haemoproteus species and 2) the extremely attenuated width of the growing dumbbell-shaped macro- and microgametocytes. Additionally, Haemoproteus erythrogravidus is shown to be a monophyletic taxon that diverges from Haemoproteus coatneyi at the molecular level. We provide the complete mitochondrial DNA genome for both H. coatneyi and H. erythrogravidus. Molecular and morphological evidences indicate that H. erythrogravidus is present in Ecuador and Colombia, and genetic lineages with 100% of identity for the cyt b gene were reported in Chile, Perú, and Venezuela. Our study also indicates that H. erythrogravidus and H. coatneyi are sympatric sister taxa sharing Z. capensis as a host species across its distribution, which could be the result of sympatric speciation or complex biogeographic processes. Further studies on the distribution and evolutionary history of Z. capensis and its parasites H. erythrogravidus and H. coatneyi insight for our better understanding of the factors and dynamics driving parasite speciation.


Assuntos
Doenças das Aves/parasitologia , Aves/parasitologia , DNA de Protozoário/genética , Haemosporida/classificação , Haemosporida/genética , Parasitos/classificação , Infecções Protozoárias em Animais/parasitologia , Animais , Citocromos b/genética , DNA Mitocondrial , Genoma Mitocondrial , Filogenia , América do Sul
18.
Acta biol. colomb ; 20(1): 217-220, ene.-abr. 2015. ilus, tab
Artigo em Inglês | LILACS | ID: lil-734923

RESUMO

Little is known about the oviposition habits and egg structure of Neotropical members of the Simuliidae family. The oviposition behavior of Simulium dinellii (Joan) was observed near at Otún Quimbaya, Colombia. Small groups of females hovered about 2 cm above the water surface to oviposit. Some of these females had been capture and the eggs were obtained. These eggs were counted, measured and processed by scanning electron microscopy. Subtriangular eggs had a latticework of polygons on the endochorionic surface. Chorionic differences between the eggs of S. dinellii and the few previously studied species suggest potential taxonomic value of egg microstructure.


El conocimiento sobre los hábitos de oviposición y estructura de los huevos de la familia Simuliidae es muy escaso. En este estudio se observó el comportamiento de oviposición de Simulium dinellii (Joan) en quebradas cercanas al Santuario de fauna y flora Otún Quimbaya, Colombia. El cual consistió en la formación de pequeños grupos de hembras que sobrevolaban a 2 cm de la superficie del agua para ovipositar, algunas de estas hembras fueron colectadas, obteniendo así los huevos, los cuales fueron contados, medidos y procesados por Microscopia Electrónica de Barrido con el fin de caracterizar la estructura endocoriónica. Los huevos presentaron una forma subtriangular, con una entramado poligonal sobre la superficie. Las características morfológicas observadas en los huevos de S. dinellii fueron diferentes a las previamente reportadas en otras especies de la familia Simuliidae, sugiriendo un posible valor taxonómico de la microestructura del huevo.

19.
Artigo em Inglês | MEDLINE | ID: mdl-26737975

RESUMO

In this paper, we propose a parametric approach for the assessment of wall motion in Left Ventricle (LV) function in cardiac cine-Magnetic Resonance Imaging (MRI). Time-signal intensity curves (TSICs) are identified in Spatio-temporal image profiles extracted from different anatomical segments in a cardiac MRI sequence. Different parameters are constructed from specific TSICs that present a decreasing then increasing shape reflecting dynamic information of the LV contraction. The parameters extracted from these curves are related to: 1) an average curve based on a clustering process, 2) curve skewness and 3) cross correlation values between each average clustered curve and a patient-specific reference. Several tests are performed in order to construct different vectors to train a sparse classifier based on kernel Dictionary Learning (DL). Results are compared with other classifiers like Support Vector Machine (SVM) and Discriminative Dictionary Learning. The best classification performance is obtained with information of skewness and the average curve with an accuracy about 94% using the mentioned sparse based kernel DL with a radial basis function kernel.


Assuntos
Algoritmos , Ventrículos do Coração/fisiopatologia , Coração/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Estudos de Casos e Controles , Análise por Conglomerados , Humanos , Processamento de Sinais Assistido por Computador , Máquina de Vetores de Suporte , Fatores de Tempo
20.
Parasitol Res ; 112(12): 4193-204, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24048707

RESUMO

Plasmodium (Novyella) unalis sp. nov. was found in the Great Thrush, Turdus fuscater (Passeriformes, Turdidae) in Bogotá, Colombia, at 2,560 m above sea level where the active transmission occurs. This parasite is described based on the morphology of its blood stages and a fragment of the mitochondrial cytochrome b gene (lineage UN227). Illustrations of blood stages of new species are given, and the phylogenetic analysis identifies closely related species and lineages of avian malaria parasites. The new species is most similar to Plasmodium (Novyella) vaughani (lineage SYAT05), a cosmopolitan avian malaria parasite; these parasites are also closely related genetically, with a genetic difference of 3.2% between them. P. unalis can be readily distinguished from the latter species morphologically, primarily due to the (1) presence of a single large, circular shaped pigment granule in the erythrocytic trophozoites and meronts; (2) presence of prominent vacuoles in trophozoites and growing meronts; and (3) presence of predominantly fan-like shaped erythrocytic meronts. Cytochrome b lineages with high similarity to the new species have been reported in Costa Rica, Brazil, Chile, and USA. It is probable that the new species of malaria parasite is widely distributed in the New World. This parasite has been reported only in the Great Thrush at the study site and might have a narrow range of avian hosts. Records of P. unalis are of particular theoretical interest due to its active transmission at highlands in Andes. Possible influence of urbanization on transmission of this malaria parasite in Bogotá is discussed.


Assuntos
Malária Aviária/parasitologia , Filogenia , Plasmodium/classificação , Aves Canoras/parasitologia , Altitude , Animais , Colômbia , Citocromos b/genética , Eritrócitos/parasitologia , Genes Mitocondriais , Genes de Protozoários , Plasmodium/citologia , Plasmodium/genética
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