520 research outputs found

    Pupil size following dark adaptation in patients with retinitis pigmentosa

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    According to the equivalent light hypothesis, molecular defects in the photoreceptor lead to a continuous activation of the photoreceptor cascade in a manner equivalent to real light. the consequences in diseases such as retinitis pigmentosa (RP) are as disruptive to the cells as real light. Two forms of the equivalent light hypothesis can be distinguished: strong - mutations in rhodopsin or other cascade proteins in some forms of RP continuously excite the visual phototransduction cascade, weak - disruption of outer segments in all patients with RP eliminates circulating dark current and blocks neurotransmitter release in a manner similar to real light. Both forms of the equivalent light hypothesis predict that pupils of patients with RP will be constricted like those of normal subjects in the light. the purpose of this study was to test the equivalent light hypothesis by determining whether steady-state pupil diameter following full dark adaptation is abnormally small in any of a sample of patients with RP. Thirty-five patients with RP and 15 normal subjects were tested. Direct steady-state pupillometric measures were obtained from one eye in a full-field dome after 45 min of dark adaptation by videotaping the pupil with an infrared camera. Mean pupil diameter in the dark was comparable (t = -0.15. P = 0.88) between patients with RP (6.85 +/- 0.58 min) and normal subjects (6.82 +/- 0.76 mm). the results of the present study are clearly counter to the prediction of the second (weaker) form of the equivalent light hypothesis.Universidade Federal de São Paulo, Dept Oftalmol, BR-04023062 São Paulo, SP, BrazilRetina Fdn SW, Dallas, TX USAUniversidade Federal de São Paulo, Dept Oftalmol, BR-04023062 São Paulo, SP, BrazilWeb of Scienc

    Efeito Da Temperatura Sobre O Crescimento Micelial De Trichoderma, Sclerotinia Minor E S. Sclerotiorum E Sobre O Micoparasitismo

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    Environmental conditions are very important for the biological control of plant diseases. In a previous study, isolates of Trichoderma asperellum (IBLF 897, IBLF 904 and IBLF 914) and T. asperelloides (IBLF 908) were selected as antagonists of S. minor and S. sclerotiorum, causal agents of lettuce drop, one of the most relevant diseases affecting the lettuce crop. In this subsequent study, the mycelial growth of these isolates and pathogens, as well as the mycoparasitism of isolate IBLF 914, was evaluated at different temperatures. The mycelial growth of the isolates of T. asperellum and T. asperelloides, as well as of S. minor and S. sclerotiorum, was evaluated at temperatures ranging from 7 to 42°C. The parasitism of propagules of S. minor and S. sclerotiorum by the isolate IBLF 914, as well as the number of lettuce seedlings surviving drop, was evaluated at 12, 17, 22, 27 and 32°C, in gerboxes containing substrate. S. minor and S. sclerotiorum showed mycelial growth at temperatures ranging from 7 to 27°C, but no growth occurred at 32 °C, and both pathogens had greater mycelial growth at 22°C. The isolates of Trichoderma grew at temperatures ranging from 12 to 37°C, with maximum growth at 27°C. The isolate IBLF 914 had mycoparasitism and reduced the disease in lettuce seedlings at temperatures ranging from 22 to 32°C. Since lettuce drop occurs when mild temperatures and high humidity prevail and the antagonist was more effective at higher temperatures, it is recommended that Trichoderma is applied in lettuce fields in Brazil also during warmer months of the year to reduce the inoculum remaining in the soil before planting the winter crop, which is more affected by the disease. © 2016, Universidade Estadual Paulista (UNESP). All rights reserved.42322222

    Influence of water and ultraviolet irradiation on the induction period of the oxidation of biodiesel

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    Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Biodiesel degrades due to oxidative processes, causing a decrease in its quality. In the present work, it has been clearly shown that the incidence of ultraviolet radiation on biodiesels obtained from soy, canola, linseed and microalgae oils initiate oxidative processes which lead to the decrease in the induction period (IP) of the fuel. The influence of the residual water content of the same biodiesels on the oxidation process was also investigated with and without the incidence of ultraviolet radiation. Between 190 and 850 ppm of water in the biodiesel and without UV irradiation, no significant change in the IP values was observed under the experimental conditions.Biodiesel degrades due to oxidative processes, causing a decrease in its quality. In the present work, it has been clearly shown that the incidence of ultraviolet radiation on biodiesels obtained from soy, canola, linseed and microalgae oils initiate oxid284676680FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)sem informaçãosem informaçãoThe authors are grateful to CNPq for financial support and to Dr. Fabio Batista (EXTRAE-UNICAMP) who graciously provided the microalgae oi

    Conditioning temperature for inducing uniform ripening of 'Abate Fetel' pears.

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    The aim of this study was to determine the conditioning temperature period for inducing uniform ripening of ‘Abate Fetel’ pears as well as to determine the maximum storage period with no quality loss. Three harvests were carried out at weekly intervals and each harvest date was considered a factorial experiment (7x3), with seven storage periods at 0 ± 1 °C and 90 ± 5% relative humidity (0; 20; 40; 60; 80; 100 and 120 days) and three periods at room temperature (20 ± 1 °C) (zero, three and six days). The assessed quality attributes were flesh firmness, starch content, weight loss and soluble solids content. Acceptance and purchase intention sensory tests were carried out. Cold storage was efficient in inducing uniform ripening in ‘Abate Fetel’ pears after 20 days at low temperature followed by six days at room temperature for fruit from the three harvest dates. ‘Abate Fetel’ pears harvested at harvest maturity of 57 N can be stored for up to 120 days and commercialized within six days with no quality loss. However, fruit harvested at flesh firmness below 55 N can be stored for 80 days and commercialized within six days or stored for 100 days and commercialized within three days. Key words: Pyrus communis L.. Cold storage. Acceptance. Shelf life. O objetivo deste trabalho foi de definir o tempo necessário de condicionamento por frio para causar a uniformização do amadurecimento de peras ‘Abate Fetel’. Ainda, objetivou-se a determinação do período máximo de armazenamento sem que houvesse prejuízos à qualidade de frutos. Foram realizadas três colheitas em intervalos semanais e cada colheita constituiu um experimento fatorial (7x3), sendo sete períodos de manutenção sob baixa temperatura (0; 20; 40; 60; 80; 100 e 120 dias) e três períodos de manutenção em ambiente simulado a 20 ± 1 °C (zero, três e seis dias). Os atributos de qualidade avaliados foram firmeza de polpa, índice de degradação do amido, perda de massa fresca, teores de sólidos solúveis e aceitabilidade. O condicionamento por frio foi eficiente na indução e uniformização do amadurecimento de peras ‘Abate Fetel’, após 20 dias de manutenção em baixa temperatura seguidos de seis dias em ambiente simulado, para os frutos provenientes das três datas de colheita. Frutos da cultivar Abate Fetel com data de colheita DC1 podem ser armazenados por até 120 dias e comercializados em até seis dias sem que haja comprometimento da qualidade. Já frutos colhidos nas datas de colheita DC2 e DC3 podem ser armazenados por 80 dias e comercializados em até seis dias ou armazenados por 100 dias e comercializados no período de três dias. Palavras-chave: Pyrus communis L.. Armazenamento refrigerado. Aceitabilidade

    New records of <i>Calamodontophis paucidens</i> (Serpentes: Colubridae: Xenodontinae) from Brazil and Uruguay

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    Amaral (1935) described the new genus and species Calamodon paucidens based upon one specimen collected at 'vila Sao Simao', municipality of Cacequi (29" 53' S: 54" 49' W), state of Rio Grande do Sul (RS), Brazil. The name Calamodon was preoccupied, being replaced by Calamodontophys (AmaraI,1963).Asociación Herpetológica Argentina (AHA

    RETINAL DEGENERATION IN A PIT BULL DOG: ELECTRORETINOGRAPHIC FINDINGS

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    Electroretinogram (ERG) is a non-invasive electrophysiologic test widely used in both human and veterinary ophthalmology to evaluate retinal function. Case report: due to recent cases of severe visual impairment in Pit Bull dogs in our clinic, we decided to evaluate the retinal function by full-field ERG in a 5-month-old male Pit Bull dog whose owner have noticed visual impairment since 40 days of age. Under general anesthesia, the dog was submitted to full-field ERG testing, according to ISCEV (International Society for Clinical Electrophysiology of Vision) standard protocol. ERG recordings were obtained in one eye after 30 minutes of dark adaptation from a fully dilated pupil, using a monopolar contact lens electrode. Non-detectable scotopic and photopic responses were found, confirming the devastating effect of the retinal degeneration. Conclusion: ERG was able to quantify the severity of retinal degeneration on retinal function. We believe that heredogram study of these animals may be helpful to better understand this new retinal condition affecting Pit Bull dogs.O eletrorretinograma (ERG) consiste em exame objetivo, não invasivo, capaz de avaliar a função retiniana tanto na oftalmologia humana como na veterinária. Caso Clínico: com o recente surgimento em São Paulo, de cães da raça Pit Bull apresentando déficit visual severo, optou-se por realizar ERG de campo total em um filhote macho, 5 meses de idade, com baixa de visão desde os 40 dias de idade, com intuito de avaliar sua função retiniana. O animal, sob anestesia geral, foi submetido ao ERG, segundo o protocolo padrão da ISCEV (International Society for Clinical Electrophysiology of Vision). Em um dos olhos foi adaptado eletrodo de lente de contato monopolar, após adaptação ao escuro por 30 minutos e dilatação completa da pupila. As respostas escotópicas e fotópicas mostraram-se não detectáveis, confirmando o efeito devastador da degeneração na função retiniana. Comentários conclusivos: o Erg foi capaz de detectar a severidade da degeneração retiniana e acredita-se que o estudo do heredograma destes animais possibilitará melhor compreensão desta nova doença

    Espécimes de pau-rosa (Aniba rosaeodora Ducke - Lauraceae) na Floresta Nacional ods Tapajós: espécie nativa ameaçada de extinção na Amazônia.

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    O Pau-Rosa (Aniba rosaeodora Ducke - Lauraceae) é a planta aromática amazônica mais conhecida e importante no comércio de óleos essenciais. Seu óleo é obtido por destilação das folhas, galhos, madeira e raízes, sendo rico em linalol. O produto tem grande demanda no mercado nacional e internacional por ser utilizado na aromaterapia, bem como na perfumaria de alto valor econômico. O corte indiscriminado e manejo inadequado fez com que a espécie fosse incluída pelo IBAMA na Lista Oficial de Espécies da Flora Brasileira Ameaçadas de Extinção. Também é classificada pela Red- List/IUCN na categoria Ameaçada, critério ?em perigo?. Diante disso, o objetivo deste trabalho foi identificar indivíduos na Floresta Nacional do Tapajós como possíveis matrizes de conservação genética nessa Unidade de Conservação e na região. Para identificar os indivíduos existentes realizou-se uma campanha de campo, em 2012, adotaram-se como ponto de referência os quilômetros 67 e 83 da Rodovia BR 163 que liga Santarém a Cuiabá, onde se localizam portões de acesso as áreas estudadas. As atividades obedeceram às normas de pesquisa de campo estabelecidas pelo ICMBIO. Para cada indivíduo identificado por parataxônomo e mateiro obteve-se a localização com auxílio do GPS (Global Positioning System), posteriormente foi elaborado o mapa em Sistema de Informações Geográficas. Foram identificados 15 indivíduos, sendo que 93,3% estavam em ocorrências isoladas
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