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1.
Entropy (Basel) ; 25(6)2023 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-37372204

RESUMO

The discovery of quantum algorithms offering provable advantages over the best known classical alternatives, together with the parallel ongoing revolution brought about by classical artificial intelligence, motivates a search for applications of quantum information processing methods to machine learning. Among several proposals in this domain, quantum kernel methods have emerged as particularly promising candidates. However, while some rigorous speedups on certain highly specific problems have been formally proven, only empirical proof-of-principle results have been reported so far for real-world datasets. Moreover, no systematic procedure is known, in general, to fine tune and optimize the performances of kernel-based quantum classification algorithms. At the same time, certain limitations such as kernel concentration effects-hindering the trainability of quantum classifiers-have also been recently pointed out. In this work, we propose several general-purpose optimization methods and best practices designed to enhance the practical usefulness of fidelity-based quantum classification algorithms. Specifically, we first describe a data pre-processing strategy that, by preserving the relevant relationships between data points when processed through quantum feature maps, substantially alleviates the effect of kernel concentration on structured datasets. We also introduce a classical post-processing method that, based on standard fidelity measures estimated on a quantum processor, yields non-linear decision boundaries in the feature Hilbert space, thus achieving the quantum counterpart of the radial basis functions technique that is widely employed in classical kernel methods. Finally, we apply the so-called quantum metric learning protocol to engineer and adjust trainable quantum embeddings, demonstrating substantial performance improvements on several paradigmatic real-world classification tasks.

2.
Indian J Ophthalmol ; 71(6): 2500-2503, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37322670

RESUMO

Purpose: Glaucoma is the second leading cause of blindness worldwide, affecting more than 64 million people aged 40-80. The best way to manage primary open-angle glaucoma (POAG) is by lowering the intraocular pressure (IOP). Netarsudil is a Rho kinase inhibitor, the only class of antiglaucoma medications that reorganizes the extracellular matrix to improve the aqueous outflow through the trabecular pathway. Methods: An open-label, real-world, multicentric, observation-based 3-month study was performed for assessing the safety and ocular hypotensive efficacy of netarsudil ophthalmic solution (0.02% w/v) in patients with elevated IOP. Patients were given netarsudil ophthalmic solution (0.02% w/v) as a first-line therapy. Diurnal IOP measurements, best-corrected visual acuity, and adverse event assessments were recorded at each of the five visits (Day-1: screening day and first dosing day; subsequent observations were taken at 2 weeks, 4 weeks, 6 weeks, and 3 months). Results: Four hundred and sixty-nine patients from 39 centers throughout India completed the study. The mean IOP at baseline of the affected eyes was 24.84 ± 6.39 mmHg (mean ± standard deviation). After the first dose, the IOP was measured after 2, 4, and 6 weeks, with the final measurement taken at 3 months. The percentage reduction in IOP in glaucoma patients after 3 months of once-daily netarsudil 0.02% w/v solution use was 33.34%. The adverse effects experienced by patients were not severe in the majority of cases. Some adverse effects observed were redness, irritation, itching, and others, but only a small number of patients experienced severe reactions, as reported in a decreasing order: redness > irritation > watering > itching > stinging > blurring. Conclusion: We found that netarsudil 0.02% w/v solution monotherapy when used as the first-line treatment in primary open-angle glaucoma and ocular hypertension was both safe and effective.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Glaucoma de Ângulo Aberto , Glaucoma , Hipertensão Ocular , Humanos , Soluções Oftálmicas , Hipertensão Ocular/diagnóstico , Glaucoma/tratamento farmacológico , Pressão Intraocular , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/tratamento farmacológico , Anti-Hipertensivos/uso terapêutico , Resultado do Tratamento
3.
Artigo em Inglês | MEDLINE | ID: mdl-20734051

RESUMO

Many animal species make use of ultraviolet (UV) light in a number of behaviors, such as feeding and mating. The goldfish (Carassius auratus) is among those with a UV photoreceptor and pronounced UV sensitivity. Little is known, however, about the retinal processing of this input. We addressed this issue by recording intracellularly from second-order neurons in the adult goldfish retina. In order to test whether cone-driven horizontal cells (HCs) receive UV cone inputs, we performed chromatic adaptation experiments with mono- and biphasic HCs. We found no functional evidence of a projection from the UV-sensitive cones to these neurons in adult animals. This suggests that goldfish UV receptors may contact preferentially triphasic HCs, which is at odds with the hypothesis that all cones contact all cone-driven HC types. However, we did find evidence of direct M-cone input to monophasic HCs, favoring the idea that cone-HC contacts are more promiscuous than originally proposed. Together, our results suggest that either UV cones have a more restricted set of post-synaptic partners than the other three cone types, or that the UV input to mono- and biphasic HCs is not very pronounced in adult animals.


Assuntos
Vias Neurais/fisiologia , Retina/fisiologia , Células Fotorreceptoras Retinianas Cones/fisiologia , Células Horizontais da Retina/fisiologia , Raios Ultravioleta , Animais , Carpa Dourada , Vias Neurais/citologia , Vias Neurais/efeitos da radiação , Retina/citologia , Retina/efeitos da radiação , Células Fotorreceptoras Retinianas Cones/citologia , Células Fotorreceptoras Retinianas Cones/efeitos da radiação , Células Horizontais da Retina/citologia , Células Horizontais da Retina/efeitos da radiação , Visão Ocular/fisiologia , Visão Ocular/efeitos da radiação
4.
BMJ Open ; 8(3): e019434, 2018 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-29567845

RESUMO

OBJECTIVES: Mounting evidence links positive psychological functioning to restorative health processes and favourable medical outcomes. However, very little is known about the relationship between optimism, an indicator of psychological functioning and the American Heart Association (AHA)-defined concept of cardiovascular health (CVH), particularly in Hispanics/Latinos of diverse backgrounds. To address limitations of existing literature, this study investigated the association between dispositional optimism and CVH in a heterogeneous sample of Hispanics/Latinos residing in the USA. DESIGN: Cross-sectional study. PARTICIPANTS AND SETTING: Data were analysed from 4919 adults ages 18-75 of the Hispanic Community Health Study/Study of Latinos parent study and the Sociocultural Ancillary Study. MAIN OUTCOME MEASURES: Optimism was assessed using the 6-item Life Orientation Test-Revised (range from 6 to 30). AHA classification standards were used to derive an additive CVH score with operationalisation of indicators as Ideal, Intermediate and Poor. The overall CVH score included indicators of diet, body mass index, physical activity, cholesterol, blood pressure, fasting glucose and smoking status. Multivariate linear and logistic regressions were used to examine associations of optimism with CVH (Life's Simple 7), after adjusting for sociodemographic factors and depressive symptoms. RESULTS: Each increase in the optimism total score was associated with a greater CVH score (ß=0.03 per unit increase, 95% CI 0.01 to 0.05). When modelling tertiles of optimism, participants with moderate (ß=0.24 to 95% CI 0.06 to 0.42) and high (ß=0.12, 95% CI 0.01 to 0.24) levels of optimism displayed greater CVH scores when compared with their least optimistic peers. CONCLUSION: This study offers preliminary evidence for an association between optimism and CVH in a large heterogeneous group of Hispanic/Latino adults. Our study adds scientific knowledge of psychological assets that may promote CVH and suggests a novel therapeutic target for consideration. Future studies are needed to explore causality and potential mechanism underlying the relationship between positive emotion and heart health.


Assuntos
Doenças Cardiovasculares/classificação , Doenças Cardiovasculares/etnologia , Depressão/etnologia , Hispânico ou Latino/psicologia , Otimismo , Adolescente , Adulto , Idoso , American Heart Association/organização & administração , Pressão Sanguínea , Índice de Massa Corporal , Doenças Cardiovasculares/etiologia , Colesterol/sangue , Estudos Transversais , Dieta , Exercício Físico , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Índice de Gravidade de Doença , Fumar/etnologia , Estados Unidos/epidemiologia , Adulto Jovem
5.
Indian J Ophthalmol ; 65(11): 1228-1232, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29133662

RESUMO

Ticks are tiny crawling bugs in the spider family that feed by sucking blood from animals. They are second only to mosquitoes as vectors of human disease, both infectious and toxic. Infected ticks spread over a hundred diseases, some of which are fatal if undetected. They spread the spirochete (which multiplies in the insect's gut) with a subsequent bite to the next host. We describe the only reported cases of peri ocular tick bite from India that presented to us within a span of 3 days and its management. Due suspicion and magnification of the lesions revealed the ticks which otherwise masqueraded as small skin tags/moles on gross examination. The ticks were firmly latched on to the skin and careful removal prevented incarceration of the mouth parts. Rickettsial diseases that were believed to have disappeared from India are reemerging and their presence has recently been documented in at least 11 states in the country. Among vector borne diseases, the most common, Lyme disease, also known as the great mimicker, can present with rheumatoid arthritis, fibromyalgia, depression, attention deficit hyperactivity disorder, multiple sclerosis, chronic fatigue syndrome, cardiac manifestations, encephalitis, and mental illness, to name some of the many associations. Common ocular symptoms and signs include conjunctivitis, keratitis, uveitis, and retinitis. Early detection and treatment of tick borne diseases is important to prevent multi system complications that can develop later in life.


Assuntos
Infecções Oculares Parasitárias/diagnóstico , Doenças Palpebrais/diagnóstico , Doenças do Aparelho Lacrimal/diagnóstico , Doenças Transmitidas por Carrapatos/diagnóstico , Carrapatos , Animais , Pré-Escolar , Infecções Oculares Parasitárias/parasitologia , Infecções Oculares Parasitárias/cirurgia , Doenças Palpebrais/parasitologia , Doenças Palpebrais/cirurgia , Feminino , Humanos , Doenças do Aparelho Lacrimal/parasitologia , Doenças do Aparelho Lacrimal/cirurgia , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Oftalmológicos , Doenças Transmitidas por Carrapatos/parasitologia , Doenças Transmitidas por Carrapatos/cirurgia
6.
PLoS One ; 11(1): e0147318, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26800521

RESUMO

A new method is presented to determine the retinal spectral sensitivity function S(λ) using the electroretinogram (ERG). S(λ)s were assessed in three different species of myomorph rodents, Gerbils (Meriones unguiculatus), Wistar rats (Ratus norvegicus), and mice (Mus musculus). The method, called AC Constant Method, is based on a computerized automatic feedback system that adjusts light intensity to maintain a constant-response amplitude to a flickering stimulus throughout the spectrum, as it is scanned from 300 to 700 nm, and back. The results are presented as the reciprocal of the intensity at each wavelength required to maintain a constant peak to peak response amplitude. The resulting S(λ) had two peaks in all three rodent species, corresponding to ultraviolet and M cones, respectively: 359 nm and 511 nm for mice, 362 nm and 493 nm for gerbils, and 362 nm and 502 nm for rats. Results for mouse and gerbil were similar to literature reports of S(λ) functions obtained with other methods, confirming that the ERG associated to the AC Constant-Response Method was effective to obtain reliable S(λ) functions. In addition, due to its fast data collection time, the AC Constant Response Method has the advantage of keeping the eye in a constant light adapted state.


Assuntos
Eletrorretinografia/métodos , Animais , Gerbillinae , Camundongos , Ratos , Ratos Wistar , Software
9.
AIDS Public Policy J ; 20(3-4): 66-73, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-17624030

RESUMO

The rapid scale-up (that is, full implementation) of programs to provide antiretroviral therapy (ART) for HIV in resource-poor settings has become a major objective for many less-developed nations and the agencies that provide funding to them. The success and sustainability of ART programs will depend upon durable viral suppression, the long-term maintenance of the infected on first-line treatment regimes. This article considers the data policy that will be required to achieve durable viral suppression. The UNAIDS (Joint United Nations Programme on HIV/AIDS) "Three Ones" doctrine calls for one national health information strategy for countries that are scaling-up ART. This article provides a framework for standardizing national data policy. The need for standardization must be balanced with recognition that ART programs are still evolving and that excess standardization (imposing forms and electronic systems) should be avoided while best practices are developed and proven. This independent assessment of data policy for ART may be useful in the further development of routine program monitoring and targeted evaluation of durable viral suppression.


Assuntos
Antivirais/uso terapêutico , Sistemas de Gerenciamento de Base de Dados/normas , Infecções por HIV/tratamento farmacológico , Política de Saúde , Guias de Prática Clínica como Assunto , Países em Desenvolvimento , Terapia Diretamente Observada/normas , Infecções por HIV/virologia , Acessibilidade aos Serviços de Saúde/normas , Humanos , Nações Unidas
10.
Indian J Ophthalmol ; 63(3): 262-4, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25971174

RESUMO

Fibromas are benign tumors that are composed of fibrous or connective tissue. They can grow in all organs, arising from mesenchymal tissue (a type of loose connective tissue). The term "fibroblastic" or "fibromatous" is used to describe tumors like the fibroma. This 69-year-old male presented to us with giant, multiple, very slowly progressive, painless, noninflammatory, soft, trans-illuminant, pedunculated lid swellings with a two decade history. There were no other swellings on the body. He was clinically normal on systemic examination except for the immature cataracts in both eyes. The diagnosis was confirmed on histopathology. Simple excision removed all the soft fibromas virtually leaving no scar. A review of literature world-wide using Medline Plus/PubMed revealed this to be the only reported case of multiple giant soft fibromas of the lid.


Assuntos
Neoplasias Palpebrais/diagnóstico , Pálpebras/patologia , Fibroma/diagnóstico , Idoso , Humanos , Masculino
11.
Indian J Ophthalmol ; 63(6): 524-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23571244

RESUMO

A seventy-year-old male presented with dense asteroid hyalosis in both eyes. He had undergone cataract extraction in one eye 3 years ago, and the other eye had immature cataract. Both the autorefractor and dilated streak retinoscopy did not give readings and subjective visual improvement could not be achieved. Immediately following YAG posterior capsulotomy and anterior vitreous asteroid disruption, the vision improved to 20/20 with recordable auto refractor and streak retinoscopy values. Our initial experience indicates that the treatment is simple, safe and effective but needs controlled and prospective studies to confirm its long-term safety.


Assuntos
Opacificação da Cápsula/cirurgia , Terapia a Laser/métodos , Lasers de Estado Sólido/uso terapêutico , Facoemulsificação/efeitos adversos , Cápsula Posterior do Cristalino/cirurgia , Capsulotomia Posterior/métodos , Idoso , Opacificação da Cápsula/etiologia , Opacificação da Cápsula/patologia , Humanos , Masculino , Cápsula Posterior do Cristalino/patologia
12.
Nutr Hosp ; 31(3): 1254-63, 2014 Dec 17.
Artigo em Espanhol | MEDLINE | ID: mdl-25726220

RESUMO

OBJECTIVE: To evaluate whether more positive self-perception of physical fitness is associated with lower prevalence of metabolic syndrome (MetS) and its components in university students in Bogotá, Colombia Method: A total of 493 men (mean age 28.5±11.5 years old) without cardiovascular disease university students completed the self-report fitness tool, namely "The International FItness Scale" (IFIS). The overall prevalence of MetS and its components according to "International Diabetes Federation" (IDF) criteria and the "National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood, Cholesterol in Adults" (NCEP: ATP-III) were measured. Body Fat Mass (BFM), Body Fat Percentage (BF %), Fat-Free Mass (FFM) and Fat-Free Mass Index (FFMI), were estimated using segmental bioelectrical impedance equipment. RESULTS: Twenty three percent of participants had met the criteria of MetS. Central obesity (33%) was the most prevalent factor, followed by low HDL cholesterol level (31%). The other factors associated with the presence of MetS were hypercholesterolemia (60%), high LDL cholesterol level (32%) and hypertriglyceridemia (19%). Participants reporting to have a "good/very good" in the self-reported (cardiorespiratory and muscle fitness specific components), shown a healthy range in blood pressure, FFM, FFMI and triglycerides level (p <0.05). After adjustment for age and BMI, participants reporting to have a "good/very good" had lower prevalence in the components central obesity, blood pressure, triglycerides and HDL cholesterol level than those grouped in "acceptable" and/or "very poor/poor" (p <0.05). CONCLUSION: Participants with a lower self-perception of physical fitness have an increased prevalence of MetS and its components. This study suggests that the self-report tool used in this study, the IFIS tool, is a useful method to be used in large scale surveys and epidemiological studies in which, because of time, equipment, or qualified personnel limitations, fitness cannot be directly measured.


Objetivo: Evaluar si la auto-percepción de la condición física (CF) se relaciona con la frecuencia y componentes del síndrome metabólico (SM) en una muestra de estudiantes universitarios de Bogotá, Colombia. Método: Un total de 493 varones (edad 28,5±11,5 años) universitarios sin enfermedad cardiovascular previa, completaron el cuestionario de auto-reporte de la CF "The International FItness Scale" (IFIS). La identificación de los componentes relacionados al SM se establecieron según los criterios del "International Diabetes Federation" (IDF) y el "National Colesterol Education Program's Adult Treatment Panel III" (NCEP: ATP-III). La masa grasa (MG), el porcentaje de grasa (%G), la masa libre de grasa (MLG) y el índice de masa grasa (IMG), se estimaron con equipo de impedancia bioeléctrica segmentada. Resultados: El 23% de los participantes presentaron SM. La obesidad abdominal (33%) fue el factor más prevalente, seguido del c-HDL bajo (31%). Los demás componentes asociados a la presencia de SM fueron hipercolesterolemia (60%), c-LDL elevado (32%) e hipertrigliceridemia (19%). Los sujetos que acusaron como "bueno/muy bueno" en el auto-reporte de fitness cardiorrespiratorio/ muscular, presentaron promedios más saludables en la tensión arterial, MLG, IMG y triglicéridos (p.


Assuntos
Síndrome Metabólica/epidemiologia , Aptidão Física , Autoimagem , Adolescente , Adulto , Composição Corporal , Estudos Transversais , Impedância Elétrica , Humanos , Lipídeos/sangue , Masculino , Síndrome Metabólica/psicologia , Obesidade Abdominal/epidemiologia , Prevalência , Autorrelato , Inquéritos e Questionários , Universidades , Adulto Jovem
13.
Indian J Ophthalmol ; 60(3): 228-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22569390

RESUMO

Parasitic infestations of the eye have been reported since centuries, affecting various parts of the eye. Some are subtle, coexisting with vision, while many others damage and destroy, in part or totally, the gift of sight. This report describes a patient with live subconjunctival dipetalonema infestation of the right eye, with 22 parasites removed live in one sitting from one eye.


Assuntos
Túnica Conjuntiva/parasitologia , Doenças da Túnica Conjuntiva/parasitologia , Infecções por Dipetalonema/parasitologia , Dipetalonema/isolamento & purificação , Infecções Oculares Parasitárias/parasitologia , Idoso , Animais , Doenças da Túnica Conjuntiva/diagnóstico , Diagnóstico Diferencial , Infecções por Dipetalonema/diagnóstico , Infecções Oculares Parasitárias/diagnóstico , Humanos , Masculino
14.
Nutr. hosp ; 31(3): 1254-1263, mar. 2015. ilus, tab
Artigo em Espanhol | IBECS (Espanha) | ID: ibc-134424

RESUMO

Objetivo: Evaluar si la auto-percepción de la condición física (CF) se relaciona con la frecuencia y componentes del síndrome metabólico (SM) en una muestra de estudiantes universitarios de Bogotá, Colombia. Método: Un total de 493 varones (edad 28,5±11,5 años) universitarios sin enfermedad cardiovascular previa, completaron el cuestionario de auto-reporte de la CF 'The International FItness Scale' (IFIS). La identificación de los componentes relacionados al SM se establecieron según los criterios del 'International Diabetes Federation' (IDF) y el 'National Colesterol Education Program’s Adult Treatment Panel III' (NCEP: ATP-III). La masa grasa (MG), el porcentaje de grasa (%G), la masa libre de grasa (MLG) y el índice de masa grasa (IMG), se estimaron con equipo de impedancia bioeléctrica segmentada. Resultados: El 23% de los participantes presentaron SM. La obesidad abdominal (33%) fue el factor más prevalente, seguido del c-HDL bajo (31%). Los demás componentes asociados a la presencia de SM fueron hipercolesterolemia (60%), c-LDL elevado (32%) e hipertrigliceridemia (19%). Los sujetos que acusaron como 'bueno/muy bueno' en el auto-reporte de fitness cardiorrespiratorio/ muscular, presentaron promedios más saludables en la tensión arterial, MLG, IMG y triglicéridos (p<0,05). Tras ajustar por edad e IMC, los sujetos que respondieron 'bueno/muy bueno' presentaron menor prevalencia en los componentes obesidad central, tensión arterial, triglicéridos y c-HDL que los agrupados en 'aceptable' y/o 'muy malo/malo' (p<0,05). Conclusión: Los sujetos con menor percepción de CF presentan un incremento en la frecuencia y componentes del SM. Se sugiere la herramienta de auto-reporte IFIS como un método útil para ser utilizado en estudios epidemiológicos a gran escala, en los que, por falta de tiempo, equipamiento, o limitaciones de personal cualificado, la CF no pueda ser estimada directamente (AU)


Objective: To evaluate whether more positive self-perception of physical fitness is associated with lower prevalence of metabolic syndrome (MetS) and its components in university students in Bogotá, Colombia Method: A total of 493 men (mean age 28.5±11.5 years old) without cardiovascular disease university students completed the self-report fitness tool, namely 'The International FItness Scale' (IFIS). The overall prevalence of MetS and its components according to 'International Diabetes Federation' (IDF) criteria and the 'National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood, Cholesterol in Adults' (NCEP: ATP-III) were measured. Body Fat Mass (BFM), Body Fat Percentage (BF %), Fat-FreeMass (FFM) and Fat-Free Mass Index (FFMI), were estimated using segmental bioelectrical impedance equipment. Results: Twenty three percent of participants had met the criteria of MetS. Central obesity (33%) was the most prevalent factor, followed by low HDL cholesterol level(31%). The other factors associated with the presence of MetS were hypercholesterolemia (60%), high LDL cholesterol level (32%) and hypertriglyceridemia (19%).Participants reporting to have a 'good/very good' in the self-reported (cardiorespiratory and muscle fitness specific components), shown a healthy range in blood pressure, FFM, FFMI and triglycerides level (p <0.05). After adjustment for age and BMI, participants reporting to have a «good/very good» had lower prevalence in the components central obesity, blood pressure, triglycerides and HDL cholesterol level than those grouped in «acceptable» and/or «very poor/poor» (p <0.05). Conclusion: Participants with a lower self-perception of physical fitness have an increased prevalence of MetS and its components. This study suggests that the self-report tool used in this study, the IFIS tool, is a useful method to be used in large scale surveys and epidemiological studies in which, because of time, equipment, or qualified personnel limitations, fitness cannot be directly measured (AU)


Assuntos
Humanos , Masculino , Adulto Jovem , Adulto , Autoimagem , Imagem Corporal , Síndrome Metabólica/epidemiologia , Condicionamento Físico Humano , Estudantes/estatística & dados numéricos , Colômbia
15.
Environ Res ; 107(1): 132-8, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18045587

RESUMO

Contrast sensitivity (CS) was evaluated in 41 former workers from a lamp manufacturing plant who were on disability retirement due to exposure to mercury and 14 age-matched controls. The CS was measured monocularly using the sweep visual evoked potential (sVEP) paradigm at 6 spatial frequencies (0.2, 0.8, 2.0, 4.0, 15.0, and 30 cpd). Statistical difference (p<0.05) was found between the controls and the patient right and left eyes for 2.0 and 4.0 cpd. According the results in those spatial frequencies the eyes were classified in best and worst. Statistical differences were found between the controls and the best eyes for 2.0 and 4.0 cpd and for 0.8, 2.0, and 4.0 cpd for their worst eyes. No correlation was found between CS results and the time of exposure (mean=8.9 yr+/-4.1), time away from the mercury source (mean=6.0 yr+/-3.9), urinary mercury level at the time of work (mean=40.6 microg/g+/-36.3) or with the mercury level at the CS measurement time (mean=1.6 microg/g+/-1.1). We show the first evidence of a permanent impairment in CS measured objectively with the sVEP. Our data complement the previous psychophysical works reporting a diffuse impairment in the CS function showing a CS reduction in the low to middle spatial frequencies. In conclusion, non-reversible CS impairment was found in occupational exposure to mercury vapor. We suggest that CS measurement should be included in studies of the mercury effects of occupational exposure.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Sensibilidades de Contraste/efeitos dos fármacos , Potenciais Evocados Visuais/efeitos dos fármacos , Intoxicação por Mercúrio/diagnóstico , Mercúrio/toxicidade , Adulto , Estudos de Casos e Controles , Eletrofisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional
16.
Vis Neurosci ; 23(3-4): 437-40, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16961977

RESUMO

The objective of the present work was to determine the interaction of cone inputs in the response of horizontal cells using heterochromatic flicker photometry (HFP). Intracellular electrophysiological recordings were made in horizontal cells of isolated retinae of carp maintained in physiological solution, with the receptor side up. Sharp glass microelectrodes filled with 3 M KCl solution with resistances between 100 and 120 M Omega were used. Stimuli comprised six cycles of two 6-Hz sinusoidal light waves in counterphase adjusted for the same number of quanta: a green light (550 nm) from a monochromator with a Xenon lamp and an LED red light (628 nm). The stimulation program consisted of 10 steps with the 550-nm wave at constant amplitude, while the 628-nm wave varied in increments of 10% up to 100%, followed by another 10 steps with the 628-nm wave at constant amplitude while the 550-nm wave varied in increments of 10% up to 100%. We recorded responses from four different horizontal cell classes: H1 (monophasic, broadband, n = 37), H2 (biphasic, red-green color-opponent, n = 13), and H3 (biphasic, blue-yellow color-opponent, n = 2) cone horizontal cells; and RH (monophasic, broadband, n = 3) rod horizontal cells. H1 and RH horizontal cells showed a similar cancellation point at a heterochromatic mixture consistent with mixed inputs from 630- and 550-nm cones. No cancellation point was found for the H2 cell class. Fish H1 cells add cone inputs and signal "luminance" in light levels appropriate for cone stimulation. The same occurs with RH cells, which also signal "luminance," but in light levels appropriate for rod work. For both cell classes there is an HFP cancellation point occurring at a combination of 628-nm and 550-nm lights in opposing phase that leads to the cancellation of the cell's response. No cancellation was found for H2 and H3 cells, which are the chromatically opponent horizontal cells in lower vertebrates.


Assuntos
Carpas/fisiologia , Percepção de Cores/fisiologia , Fusão Flicker/fisiologia , Células Horizontais da Retina/fisiologia , Animais , Técnicas In Vitro , Potenciais da Membrana/fisiologia , Estimulação Luminosa/métodos , Fotometria/métodos , Retina/citologia
17.
Psico USF ; 13(2): 145-154, Dec. 2008. tab
Artigo em Inglês | Index Psi (psicologia) | ID: psi-41826

RESUMO

The present paper aims to analyze psychometric features of the Portuguese Sleep Wake Experience List (SWEL), to obtain norms and data about key sleep complaints for children. This questionnaire evaluates chronic sleep problems categorizing them into six categories of sleep complaints. A total of 900 elementary school students (2nd to 4th grade), 485 girls (53.9 percent) and 415 boys (46.1 percent), aged between 7 and 10 years (M = 8.63; SD = .82) were included in this study. The results indicated a good reliability and validity of the questionnaire, making him suitable as a screening tool for epidemiological purposes. The study shows that sleep complaints (14.7 percent) are a frequent syndrome in school-aged children, and often not reported to the parents and/or physician. In conclusion, the results revealed that the SWEL is a reliable and valid screening instrument for identifying potential sleep problems in Portuguese school-aged children population.(AU)


Este estudo pretende analisar as propriedades psicométricas da versão portuguesa do Questionário de Experiências de Sono-Vigília (SWEL) e a obtenção de normas e dados relativos às queixas de sono-chave nas crianças. Este questionário avalia os problemas de sono crônicos, classificando-os em seis categorias de queixas relativamente ao sono. Foram avaliadas 900 crianças do 1º CEB (2º-4º ano), 485 delas são meninas (53,9 por cento) e 415 meninos (46,1 por cento), com idades entre os 7-10 anos (M= 8,63; DP= 0,82). Verificou-se uma boa fidelidade e validade do questionário, tornando-o uma ferramenta adequada para estudos de carácter epidemiológico. O estudo mostra que as queixas relativas ao sono (14,7 por cento) são síndromes freqüentes em crianças que 1º CEB que na maioria das vezes não são referidas pelos pais e/ou médicos. Assim, o SWEL é um instrumento de detecção válido e fiável para a identificação de potenciais problemas de sono nas crianças em idade escolar.(AU)


Assuntos
Humanos , Masculino , Feminino , Criança , Transtornos do Sono-Vigília/epidemiologia , Sono , Vigília/fisiologia
18.
Psico USF ; 13(2): 145-154, Dec. 2008. tab
Artigo em Inglês | LILACS | ID: lil-505707

RESUMO

The present paper aims to analyze psychometric features of the Portuguese Sleep Wake Experience List (SWEL), to obtain norms and data about key sleep complaints for children. This questionnaire evaluates chronic sleep problems categorizing them into six categories of sleep complaints. A total of 900 elementary school students (2nd to 4th grade), 485 girls (53.9 percent) and 415 boys (46.1 percent), aged between 7 and 10 years (M = 8.63; SD = .82) were included in this study. The results indicated a good reliability and validity of the questionnaire, making him suitable as a screening tool for epidemiological purposes. The study shows that sleep complaints (14.7 percent) are a frequent syndrome in school-aged children, and often not reported to the parents and/or physician. In conclusion, the results revealed that the SWEL is a reliable and valid screening instrument for identifying potential sleep problems in Portuguese school-aged children population.


Este estudo pretende analisar as propriedades psicométricas da versão portuguesa do Questionário de Experiências de Sono-Vigília (SWEL) e a obtenção de normas e dados relativos às queixas de sono-chave nas crianças. Este questionário avalia os problemas de sono crônicos, classificando-os em seis categorias de queixas relativamente ao sono. Foram avaliadas 900 crianças do 1º CEB (2º-4º ano), 485 delas são meninas (53,9 por cento) e 415 meninos (46,1 por cento), com idades entre os 7-10 anos (M= 8,63; DP= 0,82). Verificou-se uma boa fidelidade e validade do questionário, tornando-o uma ferramenta adequada para estudos de carácter epidemiológico. O estudo mostra que as queixas relativas ao sono (14,7 por cento) são síndromes freqüentes em crianças que 1º CEB que na maioria das vezes não são referidas pelos pais e/ou médicos. Assim, o SWEL é um instrumento de detecção válido e fiável para a identificação de potenciais problemas de sono nas crianças em idade escolar.


Assuntos
Humanos , Masculino , Feminino , Criança , Sono , Transtornos do Sono-Vigília/epidemiologia , Vigília/fisiologia
19.
Psico USF ; 12(2): 257-268, jul.-dez. 2007. graf, ilus, tab
Artigo em Português | LILACS | ID: lil-491600

RESUMO

O sono e a depressão têm sido associados, tendo-se questionado se um padrão de sono deficitário era condição necessária e suficiente para o aparecimento de sintomatologia depressiva. Este estudo procura averiguar a prevalência dos problemas de sono e da depressão em crianças em idade escolar. Foram avaliadas em dois momentos 467 crianças da escola primária, com idades compreendidas entre os 6 e os 11 anos de idade (M=8,70; DP=0,692). Os resultados revelam uma diminuição na prevalência ao longo do ano lectivo nos dois quadros nosológicos, verificando-se também uma relação negativa entre o rendimento académico e a sintomatologia depressiva nos dois momentos de avaliação (T1 rho=-0,349; p=0,000; T2 rho=-0,406; p=0,000). Serão discutidas implicação dos resultados para a avaliação e intervenção das crianças, contemplando a possibilidade de uma intervenção precoce de modo a prevenir o aparecimento de um estado depressivo na infância que venha manter ou agravar os problemas do sono.


Sleep and depression have been linked and questioned if a deficit sleep pattern were a sufficient condition for arising of depressive symptoms. This study tries to examine the prevalence of sleep problems and depression in school-aged children. Four-hundred and sixty-seven elementary school-children, aged 6 and 11 years (M= 8,70; DP=0,692) were evaluated in two moments. The results revealed that during the school-year both nosological entities reduced prevalence rates, and also a negative association between academic performance and depressive symptoms were found in both evaluation moments (T1 rho=-0,349; p=0,000; T2 rho=-0,406; p=0,000). The implications of such data for evaluation and intervention in children will be discussed, taking into account the possibility of a early interventions to prevent onset of depressive states in infancy which maintain and heighten sleep problems.


Assuntos
Humanos , Masculino , Feminino , Criança , Depressão/psicologia , Sono , Transtornos do Sono-Vigília , Baixo Rendimento Escolar
20.
Psico USF ; 10(2): 113-120, jul.-dez. 2005. tab
Artigo em Português | Index Psi (psicologia) | ID: psi-30078

RESUMO

A questão da adesão aos regimes de tratamento tem sido abordada, nos últimos anos, numa perspectiva biopsicossocial pelos investigadores. Nesse sentido, o presente estudo procura investigar a prevalência de determinados comportamentos de saúde, nomeadamente a adesão terapêutica e em que medida a percepção de saúde influencia este componente. Para isso, construímos e aplicamos o QIAT (Questionário Informativo de Adesão Terapêutica) aos utentes dum centro de saúde (N = 273). Os resultados indicam que, de um modo geral, a não-adesão não se deve ao esquecimento ou a alterações na medicação. Em relação às crenças e atitudes face aos médicos e à Medicina por parte dos utentes, existe a crença de excesso de prescrição medicamentosa, assim como uma confiança exacerbada relativa ao efeito terapêutico dos fármacos e a culpabilização dos doentes por parte dos profissionais de saúde, aquando do insucesso do tratamento(AU)

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