Localized neural loss detected by macular thickness reduction using optical coherence tomography: case report

Paciente de 22 anos, sexo masculino, notou mancha central no olho esquerdo durante um episódio da cefaléia de forte intensidade há aproximadamente 6 meses. Referia diagnóstico de enxaqueca com aura, apresentando crises recorrentes desde os 15 anos de idade. O exame oftalmológico revelou perda da camada de fibras nervosas da retina na região do feixe papilomacular do olho esquerdo. A tomografia de coerência óptica demonstrou importante redução da espessura macular, acompanhada de redução localizada da camada de fibras nervosas da retina no setor temporal do disco óptico no olho esquerdo. Avaliação sistêmica, exames de imagem e avaliação cardiovascular nada revelaram e a causa da perda da perda visual foi atribuída a possível enxaqueca retiniana, embora um evento isquêmico de outra natureza não pudesse ser descartado. Nosso caso é interessante porque demonstra que a tomografia de coerência óptica pode ser útil na detecção de perda neural localizada não apenas pela medida da camada de fibras nervosas da retina, mas também pela avaliação da espessura macular.A 22-year-old man developed a central scotoma in the left eye during an episode of severe headache 6 months previously. He had a diagnosis of migraine headaches with aura since age 15. Ophthalmic examination showed retinal nerve fiber layer thickness reduction on the papilomacular bundle in the left eye and unremarkable in the right. Optical coherence tomography documented severe macular thickness reduction and a mild and localized retinal nerve fiber layer loss on the temporal side of the optic disc in the left eye. Systemic investigation, neuroimaging and cardiovascular studies were non-revealing. The cause of his visual loss was possibly related to retinal migraine, although an ischemic episode of another origin could not be excluded. Our case is interesting because it draws attention to the fact that optical coherence tomography may be able to identify localized neural loss not only by measuring peripapillary retinal nerve fiber layer but also by means of macular thickness measurements

Assessment of the Use of Solar Desalination Distillers to Produce Fresh Water in Arid Areas

Water is an important resource for human beings, yet there are inhabited places tormented by the scarcity of it. The present study is concerned with places where, seemingly, the best way to get water is through solar distillers. These places should have, typically, high values of solar irradiation and a lack of human and economic resources to build and operate complex equipment. A set of sites scattered around the world was chosen, and then the presumed productivity and thermal efficiency that solar distillers would have if they were installed at these places was calculated. The mathematical model used with this purpose assumes steady-state operation; the values of mass of water distilled and distiller efficiency were calculated for every hour, but the results presented are annual averages. Then, an economic study was made based on local costs of construction materials for the distillers, the workforce, and the prices of water to predict the payback time of solar distillers. Finally, a study on environmental impact, particularly in terms of greenhouse gas (GHG) emissions, was made to compare reverse osmosis (RO) with solar distillation. For the sites studied, typical values of annual water output are in the range of 414 dm3/m2, for Évora, up to 696 dm3/m2, for Faya Largeau; the minimum efficiency was found for Évora, as 11.5%, and the maximum efficiency was found for Tessalit, as 15.2%. Payback times are very high, regardless of the areas of the globe where solar distillers are implanted. Regarding GHG emissions, solar distillation is preferable to RO.info:eu-repo/semantics/publishedVersio

Assessment of an Innovative Way to Store Hydrogen in Vehicles

The use of hydrogen as an alternative to fossil fuels for vehicle propulsion is already a reality. However, due to its physical characteristics, storage is still a challenge. There is an innovative way, presented in this study, to store hydrogen in conventional vehicles propelled by spark-ignition reciprocating engines and fuel cells, using hydrogen as fuel; the storage of hydrogen will be at high pressure within small spheres randomly packed in a tank, like the conventional tank of fuel used nowadays in current vehicles. Therefore, the main purpose of the present study is to assess the performance of this storage system and compare it to others already applied by car manufacturers in their cars. In order to evaluate the performance of this storage system, some parameters were taken into account: The energy stored by volume and stored by weight, hydrogen leakage, and compliance with current standards. This system is safer than conventional storage systems since hydrogen is stored inside small spheres containing small amounts of hydrogen. Besides, its gravimetric energy density (GED) is threefold and the volumetric energy density (VED) is about half when compared with homologous values for conventional systems, and both exceed the targets set by the U.S. Department of Energy. Regarding the leakage of hydrogen, it complies with the European Standards, provided a suitable choice of materials and dimensions is made.info:eu-repo/semantics/publishedVersio

Orbital space-occupying lesions: an 11-year study of cases with histopathologic analysis seen at Hospital das Clínicas of FMUSP

OBJETIVO: Estudar a incidência das lesões expansivas orbitárias submetidas à biópsia em uma casuística de 11 anos no Hospital das Clínicas da FMUSP, e avaliar quais as principais especialidades envolvidas no diagnóstico e no tratamento de tais afecções. CASUÍSTICA E MÉTODOS: Solicitou-se ao setor de arquivos do hospital todos os casos de tumores e lesões de órbita submetidas à biópsia no período de 1993 a 2004. Dos 924 prontuários obtidos, 115 foram separados após análise dos dados segundo os resultados histopatológicos obtidos. Outros 111 pacientes foram obtidos por meio dos arquivos pessoais da patologista encarregada da Oftalmologia no Departamento de Patologia, dos quais 45 pacientes foram excluídos por coincidirem com a fonte anterior. Os dados foram contabilizados e comparados com os de outros serviços. RESULTADOS: Das 181 lesões orbitárias estudadas, 70% eram primárias, 23% eram secundárias, 6% consistiam de metástases e linfomas e 1% não foi classificada. Em relação à especialidade responsável diretamente pelo paciente, 72,37% dos pacientes foram assistidos por oftalmologistas, 14,36% por cirurgiões de cabeça e pescoço, 6,62% por neurocirurgiões e 6,62% por outros setores do hospital. CONCLUSÕES: As afecções orbitárias são atendidas em sua maioria pelos oftalmologistas especializados em tal área, e ao se incluir nesta casuística outras especialidades, nota-se um aumento no número de casos de lesões tumorais secundárias quando comparada ao de outros trabalhos realizados em serviços no exterior. Há necessidade de criar-se um registro confiável dos casos de lesões expansivas orbitárias nos serviços especializados brasileiros, e confirma-se o caráter multidisciplinar do objeto deste estudo.PURPOSE: To report the incidence of orbital space-occupying lesions in an 11-year interval study of patients examined at the Hospital das Clínicas of FMUSP, and to evaluate which are the main specialties involved in the diagnosis and treatment of such conditions. METHODS: All cases of orbital space-occupying lesions in the period from 1993 to 2004 were revised. Of 924 obtained medical records, 155 were selected after histopathological analysis. Another 111 cases were gathered from the personal archives of a pathologist responsible for Ophthalmic Histopathology, from which 45 cases were excluded because they had already been included in the first source analysis. The data were analyzed and compared with the results from other institutions. RESULTS: Of the studied 181 orbital space-occupying lesions, 70% were primary, 23% secondary, 6% metastatic and lymphomas, and 1% was not classified. The most common specialties involved ophthalmologists in 72.37% of all 181 cases, head and neck surgeons in 14.36%, neurosurgeons in 6.62%, and others in 6.62%. CONCLUSIONS: The orbital mass lesions were treated mostly by an expert ophthalmologist. When other specialties were included, there was a modest increase in secondary tumor incidence when the final result was compared with previous studies on this subject. Our findings indicate that the creation of a trustworthy register of all orbital space-occupying lesions in Brazilian specialized services is necessary. The multidisciplinary character of the orbital mass lesions is corroborated by this review

Comparação entre as medidas da espessura da camada de fibras nervosas da retina e da mácula pela tomografia de coerência óptica na detecção da perda axonal progressiva decorrente à neuropatia óptica traumática

PURPOSE: To compare the optical coherence tomography retinal nerve fiber layer and macular thickness measurements for detection of progressive axonal loss following acute traumatic optic neuropathy in a longitudinal study. METHODS: Three patients with unilateral traumatic optic neuropathy were evaluated sequentially after trauma. Macular and retinal nerve fiber layer thickness measurements were obtained using optical coherence tomography weekly for five weeks and around the twelfth week after trauma. RESULTS: All patients showed progressive macular and retinal nerve fiber layer thickness reduction. The mean retinal nerve fiber layer thickness on the first week was 114 μm and reduced sequentially over the first five weeks and was 46 μm on the twelfth week. For macular parameters, the mean average thickness on the first week was 248 μm and also reduced over the first five weeks and was 218 μm on the twelfth week. When compared to the initial measurement, macular thickness average reduction rate at the 12th week was 14% while peripapillary retinal nerve fiber layer thickness average reduction rate was 59%. CONCLUSIONS: Although both measurements reduce significantly after trauma, retinal nerve fiber layer thickness measurements show greater and faster retinal neural reduction if compared to macular thickness measurements in traumatic optic neuropathy.OBJETIVO: Comparar as medidas da espessura da camada de fibras nervosas da retina e macular obtidas pela tomografia de coerência óptica na detecção da perda axonal progressiva após neuropatia óptica traumática aguda e durante o seguimento clínico. MÉTODOS: Três pacientes com neuropatia óptica traumática unilateral aguda foram avaliados sequencialmente após o trauma. Medidas da espessura macular e da camada de fibras nervosas da retina foram obtidas pela tomografia de coerência óptica semanalmente por 5 semanas consecutivas e ao redor da décima segunda semana após o trauma. RESULTADOS: Todos os pacientes apresentaram redução progressiva dos valores da espessura macular e da camada de fibras nervosas da retina. A espessura média da camada de fibras nervosas da retina foi de 114 μm na primeira semana e reduziu sequencialmente ao longo das primeiras cinco semanas e foi de 46 μm na décima segunda semana. Para parâmetros macular, a espessura média foi de 248 μm na primeira semana, e também reduziu ao longo das primeiras cinco semanas e foi de 218 μm na décima segunda semana. Quando comparado às medidas iniciais, a taxa de redução das médias da espessura macular foi 14% na décima segunda semana após o trauma, enquanto que a taxa de redução das médias da espessura da camada de fibras nervosas da retina foi 59%. CONCLUSÕES: Os valores da espessura da camada de fibras nervosas da retina apresentaram uma redução maior e mais rápida se comparada às medidas da espessura macular na neuropatia óptica traumática

Fruit maturation and in vitro germination of macaw palm embryos

Acrocomia aculeata (macaw palm) is oil producing palm tree with significant agro-industrial potential. Seed dormancy in palm species may be due to embryo immaturity, which could result from delayed embryogenesis. We evaluated the correspondence between the visual characteristics of maturing fruits and their physiological aspects and the in vitro germination capacity of the embryos. 11 fruit bunches in different stages of maturity were collected and classified in terms of the degree of maturation of the endosperm, the color of the exocarp, and the occurrence of abscission. The water and oil contents of the mesocarp and seed were determined, and lipids and proteins were identified through histochemical analyses of the mesocarp, endosperm, and embryo. The embryos from each fruit bunch were cultivated in vitro in 75% Murashige and Skoog (1962) media with added organic compounds. The water contents of the seeds varied from 71.2 to 21.1% among the different stages of fruit ripening and were related to the visual markers of fruit maturation (exocarp color ranging from dark green to brown). Lipid accumulation in the mesocarp occurred later than in the endosperm, and only occurred in fruits from bunches showing signs of abscission. Embryos from bunches in different stages of maturation showed similar germinative capacities, as well as similar patterns of lipid and protein storage. Embryogenesis in A. aculeata is precocious, and the embryos of immature fruits can be utilized for in vitro cultivation.Keywords: Acrocomia aculeata, embryo culture, embryogenesis, water content, oil contentAfrican Journal of Biotechnology Vol. 12(5), pp. 446-45

Critérios para o teste de tetrazólio na estimativa do potencial germinativo em macaúba

The objective of this study was to establish criteria for the tetrazolium test in embryos of macaw palm (Acrocomia aculeata). To develop the evaluation scheme, anatomical analyses were performed, and staining patterns were identified using a 0.5% 2,3,5-triphenyl tetrazolium chloride solution for four hours, and embryo was cultured in vitro. In one experiment, three prior seed-soaking times in water (for 12 and 24 hours, besides a control without seed pre-conditioning), associated with two color temperatures (35 and 40°C) in two seed lots were evaluated. In another experiment, three concentrations of tetrazolium solution (0.5, 0.75 and 1%), associated with two staining times (two and four hours), were tested in three seed lots. In vitro embryo culture was used to compare the results. An evaluation scheme, with ten staining patterns associated with three classes of vigor, was defined, based on the anatomy of the embryo and on the in vitro seedling development. Pre-soaking is not necessary, and staining for four hours in a solution of tetrazolium salt, at 0.5% and 35ºC, should be used.O objetivo deste trabalho foi estabelecer critérios para a aplicação do teste de tetrazólio em embriões de macaúba (Acrocomia aculeata). Para a elaboração do esquema de avaliação, foram realizadas avaliações anatômicas, identificação de padrões de coloração por solução de 2,3,5-trifenil cloreto de tetrazólio a 0,5% por quatro horas e cultivo in vitro de embriões. Em um experimento, foram avaliados três períodos de pré-condicionamento das sementes por imersão em água, por 12 e 24 horas, associados a duas temperaturas de coloração, 35 e 40ºC, em dois lotes de sementes além do controle sem pré-condicionamento. Em outro experimento, foram testadas em três lotes de sementes, três concentrações da solução de tetrazólio (0,5, 0,75 e 1%), associadas a dois tempos de coloração (duas e quatro horas). Utilizou-se o cultivo in vitro de embriões para comparação dos resultados. Um esquema de avaliação com dez padrões de coloração, associados a três classes de vigor, foi definido com base na anatomia dos embriões e no desenvolvimento de plântulas in vitro. O tratamento de pré-condicionamento em água não é necessário, e se deve aplicar o tempo de coloração de quatro horas, em solução de sal de tetrazólio, a 0,5% e 35ºC

Fatores preditivos para formação de fibrina na câmara anterior após cirurgia vitreorretiniana

Purpose: The aim of this study was to investigate possible predictive factors related to anterior chamber fibrin formation after vitreoretinal surgery in a large series of patients.Methods:The data of 185 eyes of 185 patients submitted to vitreoretinal surgery was reviewed. The following variables were evaluated: the postoperatively presence of fibrin, age, diabetes mellitus, the vitrectomy system gauge (20, 23 or 25 gauge), the type of vitreous substitute, the influence of prior surgical procedures and the combination with cataract extraction. To evaluate predictive factors for anterior chamber fibrin formation, univariate analysis was performed. A multivariate stepwise logistic regression model was adjusted to investigate factors associated with fibrin formation (p<0.05).Results:Fibrinoid anterior chamber reaction was found in 12 (6.4%) patients. For multivariate logistic regression analysis, balanced salt solution (BSS), the chance of fibrin occurrence was 5 times greater (odds ratio 4.83, CI 95% 1.302 - 17.892; p=0.019), while combination with phacoemulsification increased the chance of fibrin formation by 20 times (odds ratio 20, CI 95% 2.480 - 161.347; p=0.005). No significant difference was found regarding other variables.Conclusion: Anterior chamber fibrin formation is an unwanted complication after vitreoretinal surgery. Factors such as combined performance of phacoemulsification and the use of balanced salt solution as a vitreous substitute may predispose the occurrence of this complication.Objetivo:Avaliar os possíveis fatores relacionados à formação de fibrina na câmara anterior após cirurgia vitreorretiniana em uma grande série de casos.Métodos:Foi realizado um estudo retrospectivo, observacional, caso-controle, onde os dados de 185 olhos de 185 pacientes submetidos à cirurgia vitreorretiniana foram avaliados. Os seguintes dados foram analisados: presença ou não de fibrina na câmara anterior na primeira semana de pós-operatório, idade, presença ou não de diabetes mellitus, calibre do sistema de vitrectomia utilizado (20,23 ou 25 gauge), substituto vítreo, a influência de cirurgias oftalmológicas prévias e a realização de cirurgia de catarata combinada. Para avaliação dos fatores preditivos para formação de fibrina, a análise univariada foi realizada. O modelo de regressão logística multivariada foi utilizado para investigar os fatores associados com a formação de fibrina (p<0,05).Resultados:A presença de fibrina na câmara anterior foi encontrada em 12 (6,4%) pacientes. Pela análise de regressão logística multivariada, o uso de solução salina balanceada (BSS) como substituto vítreo, a chance da presença de fibrina foi 5 vezes maior (odds ratio 4,83, IC 95% 1,302 - 17,892; p=0,019), enquanto que a realização de cirurgia facoemulsificação combinada aumentou a chance de formação de fibrina 20 vezes (odds ratio 20, IC 95% 2,480 - 161,347; p=0,005). Nenhuma diferença estatisticamente significativa foi encontrada para as outras variáveis.Conclusão:A formação de fibrina na câmara é uma complicação indesejada após cirurgia vitreorretiniana. Fatores como realização de cirurgia de facoemulsificação combinada e o uso de BSS como substituto vítreo podem predispor a esta complicação.Universidade Federal de Juiz de ForaHospital de Olhos de Juiz de ForaUniversidade Federal de São Paulo (UNIFESP)UNIFESPSciEL