18 results on '"André Messias"'
Search Results
2. Short-pulse laser plus subthreshold diffuse laser for serous retinal detachment in dome-shaped macula
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Murilo Wendeborn Rodrigues, Thais Bastos, Annelise Nicotti Gonçalves, José Augusto Cardillo, André Messias, Eduardo Cunha de Souza, and Rodrigo Jorge
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Short-pulse laser ,Subthreshold diffuse laser ,Dome-shaped macula ,Ophthalmology ,RE1-994 - Abstract
Abstract Background First described by Gaucher and associates in 2008, dome-shaped macula (DSM) is an anterior convex protrusion of the macula visible on OCT (optical coherence tomography). Visual impairment in DSM results mainly from sub-foveal serous retinal detachment (SRD). Herein, this original study from retrospective data analysis evaluate the anatomical and functional effects of Pascal® short-pulse (SP) laser plus endpoint management (EpM) subthreshold diffuse laser (SDL) in patients with SRD due to DSM. Methods This retrospective study included seven consecutive patients (eight eyes) with SRD secondary to dome-shaped macula who underwent a comprehensive ophthalmological evaluation including logMAR BCVA, slit-lamp biomicroscopy, indirect ophthalmoscopy, and spectral-domain optical coherence tomography (SD-OCT) (Spectralis; Heidelberg Engineering, Germany) before combined Pascal® SP laser plus EpM-SDL with 1 to 6 month intervals, postoperatively, with a mean ± standard error (SE) follow-up time of 12.92 ± 1.34 months. Results Eight eyes from seven patients were analyzed in this study. At baseline, mean BCVA (LogMAR) ± standard error (SE) and mean CST (central subfield thickness)(µm) ± SE were 0.6125 ± 0.14 and 412.50 ± 24.65, respectively. After a mean follow-up time of 12.92 ± 1.34 months, mean CST (µm) ± SE and BCVA (LogMAR) ± SE were 294.75 ± 19.68 (p = 0.0078) and 0.4537 ± 0.12 (p = 0.0313), respectively. A statistically significant reduction in mean CST and an improvement in mean BCVA were noted after SRD resolution with laser therapy application. The mean serous retinal detachment resolution time (months) ± SE was 3.75 ± 1.08. No adverse events were registered, including enlargement of atrophic alterations and choroidal neovascularization. Conclusions The novel combined laser modality with Pascal® SP laser plus EpM-SDL treatment may induce subretinal fluid regression and BCVA improvement 1 year after treatment in DSM patients with SRD.
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- 2023
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3. Foveal thickness reduction after anti-vascular endothelial growth factor treatment in chronic diabetic macular edema
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Gabriel Willmann, Antonio Brunno Nepomuceno, Katharina Messias, Leticia Barroso, Ingrid U. Scott, André Messias, and Rodrigo Jorge
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764 ,diabetes ,macular edema ,bevacizumab ,ranibizumab ,optical coherence tomography ,central subfield foveal thickness ,diabetic retinopathy ,Ophthalmology ,RE1-994 - Abstract
AIM: To report foveal thickness reduction in eyes with resolution of macular edema and recovery of a foveal depression after one-year of anti-vascular endothelial growth factor (anti-VEGF) therapy for center-involving diabetic macular edema (DME). METHODS: Foveal thickness was assessed with optical coherence tomography to determine the central subfield foveal thickness (CSFT) and macular volume in 42 eyes with DME (CSFT>275 µm). Evaluations also included measurement of best-corrected visual acuity (BCVA), and were performed at baseline, and upon foveal depression recovery achieved after 12 monthly intravitreal injections of either 1.5 mg/0.06 mL bevacizumab (n=21) or 0.5 mg/0.05 mL ranibizumab (n=21). Data was compared to 42 eyes of normally sighted, non-diabetic, healthy individuals with similar age, gender and race distributions. RESULTS: Mean baseline BCVA was 0.59±0.04 and 0.32± 0.03 logMAR (P
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- 2017
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4. Comparative efficacy of two different topical povidone-iodine 5% regimens in reducing conjunctival bacterial flora: A randomized parallel double-masked clinical trial.
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Letícia Fernandes Barroso, Sarah Pereira Cazella, Antonio Brunno Nepomuceno, Luiza Toscano, Liliane Ângela de Souza Castilho, Eloísa Marcela Rueda Furlan, André Messias, Ingrid U Scott, and Rodrigo Jorge
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Medicine ,Science - Abstract
The increasing prevalence of multi-resistant bacteria is a major public health concern. Infections acquired during ophthalmic surgery are devastating. The purpose of the current study is to compare the proportion of eyes with negative bacterial cultures on all tested media after 1 versus 3 sequential drops of povidone-iodine (PI) 5% into the inferior conjunctival fornix.Patients were randomly assigned to receive 1 (PI group) drop (at time 28 minutes) or 3 (PI plus group) sequential drops (at time 0, 20 minutes and 28 minutes) of PI 5% into the inferior conjunctival sac of one randomly selected eye. A swab culture was obtained from the inferior conjunctival fornix 5 minutes before and 30 minutes after time 0. Central corneal thickness (CCT) was measured shortly before time 0 and shortly after time 30. Conjunctival swabs were incubated aerobically in enriched Thioglycolate liquid medium (meat broth) and in three solid culture media (chocolate agar, trypticase soy agar with 5% sheep blood, and Sabouraud agar).There was no significant difference in the proportion of negative cultures after intervention between groups (p = 0.1638). Also in the PI group (n = 59), the proportion of eyes with negative cultures after PI (79.7%) did not differ significantly from baseline (76.3%; p = 0.7539). However in the PI plus group (n = 61), the proportion of eyes with all negative cultures after PI (85.3%) was significantly higher than before PI (70.5%) (p = 0.0177). There was no significant difference in mean CCT before and after the intervention in both groups.Instillation of 3 sequential drops of PI was associated with a significant increase in the proportion of eyes with all negative cultures, while instillation of a single drop of PI was not associated with a significant increase in the proportion of negative cultures. Further study is warranted to determine whether the difference between the PI administration regimens is also associated with differences in the rates of postoperative ocular infections.
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- 2017
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5. Assessment of gait dynamics in rats submitted to limb ischemia Avaliação da dinâmica da marcha em ratos submetidos à isquemia de membro
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Carlos Eli Piccinato, Antônio Carlos de Sousa, William Alves do Prado, André Messias, Matheus Bredarioli, Marcelo Belini Dalio, and Edwaldo Edner Joviliano
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Claudicação Intermitente ,Doença Arterial Periférica ,Traumatismo por Reperfusão ,Ratos ,Intermittent Claudication ,Peripheral Arterial Disease ,Reperfusion Injury ,Rats ,Surgery ,RD1-811 - Abstract
PURPOSE: To describe a method for the assessment of gait dynamics in rats submitted to limb ischemia. METHODS: Twenty-four male Wistar rats (150-160g) were used. Twelve animals were submitted to limb ischemia by ligation of the common left iliac artery (ischemic group: n = 12); and a sham-operated group was used as control (n=12). After a recovery period of 6 weeks, gait dynamics was assessed by counting the complete footprints and the number of hindlimb-floor contacts during a treadmill test for five minutes at a speed of 12 m.min-1 and angulation of 15°. The number of contacts of the left hindlimb was divided by the right hindlimb values (LRR) for group comparisons. Ischemic disability was quantified by comparing the area under curve (AUC) created by plotting each contact versus time for each hindlimb. The left hindlimb ischemic disability index (LHDI), which was compared between groups, was defined by the formula: LHDI = (1- AUC left / AUC right) x 100. RESULTS: Surgery was well tolerated by all animals. Rats did not suffer tissue loss or ulcerations. Complete footprint LRR was 0.3 ± 0.08 for the ischemic group and 1.3 ± 0.9 for controls (p=0.0043). Number of contacts LLR was 0.5 ± 0.2 for the ischemic group and 1.0 ± 0.1 for the control group (p=0.0051). LHDI was 56.83 ± 10.67 for the ischemic group and 2.50 ± 13.10 for the control group (P = 0.031). CONCLUSION: Assessment of gait dynamics in rats submitted to limb ischemia could be done by footprint analysis and hindlimb contact recording during a treadmill test.OBJETIVO: Descrever um método para avaliar a dinâmica da marcha em ratos submetidos à isquemia de membro pélvico. MÉTODOS: Vinte e quatro ratos Wistar machos (150-160g) foram utilizados neste estudo experimental. Doze animais foram submetidos à isquemia de membro pélvico por meio da ligadura da artéria ilíaca comum esquerda (grupo isquêmico: n=12); e doze animais foram submetidos à cirurgia simulada e usados como controle (grupo controle: n=12). Após seis semanas de recuperação, foi realizada avaliação da dinâmica da marcha por meio da contagem de impressões plantares e da contagem de contatos pata-solo durante teste com esteira durante cinco minutos, velocidade 12 m.min-1 e angulação de 15°. Os valores do número de contatos do membro pélvico esquerdo foram divididos pelos do membro pélvico direito (razão esquerda-direita - LRR) para comparação entre os grupos. A quantificação da incapacitação isquêmica foi feita comparando a área sob a curva (AUC) da representação gráfica dos contatos versus tempo para cada membro pélvico. O índice de incapacitação isquêmica do membro pélvico esquerdo (LHDI), que foi comparado entre os grupos, foi definido pela fórmula: LHDI = (1- AUC esquerda / AUC direito) x 100. RESULTADOS: A cirurgia foi bem tolerada por todos os animais. Nenhum rato apresentou necrose tecidual ou ulceração. A LRR das impressões plantares completas foi 0,3 ± 0,08 no grupo isquêmico e 1,3 ± 0,9 no grupo controle (p=0,0043). A LRR do número de contatos foi 0,5 ± 0,2 no grupo isquêmico e 1,0 ± 0,1 no grupo controle (p=0,0051). O LHDI foi 56,83 ± 10,67 no grupo isquêmico e 2,50 ± 13,10 no grupo controle (p=0,031). CONCLUSÃO: Avaliação da dinâmica da marcha em ratos submetidos à isquemia de membro pélvico pôde ser feita por meio da contagem de impressões plantares e da contagem de contatos pata-solo durante teste com esteira.
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- 2011
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6. Safety of intravitreal metoprolol in eyes with central serous chorioretinopathy
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Annelise Nicotti Gonçalves, André Messias, Leandro Chaves, Thaís Marino de Azeredo Bastos, and Rodrigo Jorge
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Ophthalmology ,Treatment Outcome ,Central Serous Chorioretinopathy ,Physiology (medical) ,Intravitreal Injections ,Visual Acuity ,Electroretinography ,Humans ,Fluorescein Angiography ,Sensory Systems ,Tomography, Optical Coherence ,Metoprolol ,Retrospective Studies - Abstract
To investigate ocular safety of intravitreal metoprolol in eyes with central serous chorioretinopathy.Five eyes of five patients diagnosed with chronic central serous chorioretinopathy (cCSC) previously treated unsuccessfully with oral spironolactone, micropulse laser and intravitreal anti-vascular endothelial growth factor agents were enrolled and received off-label intravitreal metoprolol (50 µg/0.05 ml). Baseline and follow-up examinations included measurement of best-corrected visual acuity (BCVA), intraocular pressure, anterior chamber cellular/flare scores, vitritis classification, fluorescein and indocyanine green angiography, spectral domain optical coherence tomography and electroretinography (ERG), recorded by means of DTL electrodes and following the standard suggested by the International Society for Clinical Electrophysiology of Vision (ISCEV). The total follow-up period was 4 weeks.There were no significant differences between baseline and follow-up ERG parameters: scotopic or photopic, a- and b-wave amplitude and implicit time, nor oscillatory potentials amplitude, or whatsoever. No intraocular inflammation sign was observed. In addition, BCVA showed small improvement in 4 or kept baseline values in 1 patient. The subretinal and/or intraretinal fluid volume reduced in all patients at 1 month after treatment.Patients with refractory cCSC treated with intravitreal 50 µg/0.05 ml metoprolol showed no signs of acute ocular toxicity, along with intraretinal fluid reduction and slight BCVA improvement 1 month after injection. This data suggest that intravitreal metoprolol may be a safe alternative for cCSC.
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- 2022
7. A slow-release dexamethasone implant for cancer-associated retinopathy
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Leandro J. Chaves, Marina L. de Albuquerque, Amanda Schnorr, Francyne Cyrino, Maria Lúcia Habib, André Messias, Zelia M. Correa, and Rodrigo Jorge
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Eletroretinografia ,Ophthalmology ,Paraneoplastic ocular syndromes ,Electroretinography ,Retinopatia ,RE1-994 ,Dexametasona ,Retinopathy ,Dexamethasone ,Síndromes paraneoplásicas oculares - Abstract
This case report aims to show the anatomical and functional results of a patient diagnosed as having cancer-associated retinopathy treated with a controlled-release dexamethasone implant (Ozurdex). Anatomical outcomes were assessed using spectral domain optical coherence tomography; and functional outcomes, by measuring visual acuity, microperimetry, and mutifocal electroretinography. The follow-up period was 1 year. RESUMO Este relato de caso tem como objetivo mostrar os resultados anatômicos e funcionais de um paciente com diagnóstico de retinopatia associada ao câncer tratado com implante de liberação controlada de dexametasona (Ozurdex®). Os resultados anatômicos foram avaliados por SD-OCT e os resultados funcionais por medida de acuidade visual, microperimetria e eletrorretinograma multifocal. O período de acompanhamento foi de um ano.
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- 2022
8. Comprehensive variant spectrum of the CNGA3 gene in patients affected by achromatopsia
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Maria Solaki, Britta Baumann, Peggy Reuter, Sten Andreasson, Isabelle Audo, Carmen Ayuso, Ghassan Balousha, Francesco Benedicenti, David Birch, Pierre Bitoun, Delphine Blain, Beatrice Bocquet, Kari Branham, Jaume Català‐Mora, Elfride De Baere, Helene Dollfus, Mohammed Falana, Roberto Giorda, Irina Golovleva, Irene Gottlob, John R. Heckenlively, Samuel G. Jacobson, Kaylie Jones, Herbert Jägle, Andreas R. Janecke, Ulrich Kellner, Petra Liskova, Birgit Lorenz, Loreto Martorell‐Sampol, André Messias, Isabelle Meunier, Fernanda Belga Ottoni Porto, Eleni Papageorgiou, Astrid S. Plomp, Thomy J. L. de Ravel, Charlotte M. Reiff, Agnes B. Renner, Thomas Rosenberg, Günther Rudolph, Roberto Salati, E. Cumhur Sener, Paul A. Sieving, Franco Stanzial, Elias I. Traboulsi, Stephen H. Tsang, Balázs Varsanyi, Richard G. Weleber, Ditta Zobor, Katarina Stingl, Bernd Wissinger, Susanne Kohl, Human genetics, Amsterdam Reproduction & Development (AR&D), Clinical sciences, and Medical Genetics
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NUCLEOTIDE-GATED CHANNELS ,JAPANESE ,analysis ,Cyclic Nucleotide-Gated Cation Channels ,Color Vision Defects ,TOTAL COLOURBLINDNESS ,PATIENT ,MOLECULAR-GENETICS ,variant spectrum ,Medicine and Health Sciences ,Genetics ,in silico analysis ,Humans ,NONSENSE MUTATION ,PAKISTANI FAMILIES ,Color Vision Defects/genetics ,variant classification ,Genetics (clinical) ,Medicinsk genetik ,FUNCTIONAL-ANALYSIS ,UNFOLDED PROTEIN RESPONSE ,CNGA3 ,PHOTORECEPTOR DEGENERATION ,Cyclic Nucleotide-Gated Cation Channels/genetics ,in silico ,cyclic nucleotide-gated ion channel ,Mutation ,Retinal Cone Photoreceptor Cells ,achromatopsia ,ALPHA-SUBUNIT ,Medical Genetics - Abstract
Achromatopsia (ACHM) is a congenital cone photoreceptor disorder characterized by impaired color discrimination, low visual acuity, photosensitivity, and nystagmus. To date, six genes have been associated with ACHM (CNGA3, CNGB3, GNAT2, PDE6C, PDE6H, and ATF6), the majority of these being implicated in the cone phototransduction cascade. CNGA3 encodes the CNGA3 subunit of the cyclic nucleotide-gated ion channel in cone photoreceptors and is one of the major disease-associated genes for ACHM. Herein, we provide a comprehensive overview of the CNGA3 variant spectrum in a cohort of 1060 genetically confirmed ACHM patients, 385 (36.3%) of these carrying "likely disease-causing" variants in CNGA3. Compiling our own genetic data with those reported in the literature and in public databases, we further extend the CNGA3 variant spectrum to a total of 316 variants, 244 of which we interpreted as "likely disease-causing" according to ACMG/AMP criteria. We report 48 novel "likely disease-causing" variants, 24 of which are missense substitutions underlining the predominant role of this mutation class in the CNGA3 variant spectrum. In addition, we provide extensive in silico analyses and summarize reported functional data of previously analyzed missense, nonsense and splicing variants to further advance the pathogenicity assessment of the identified variants.
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- 2022
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9. Myopic shift in pediatric cataract surgery associated with age and surgical complications
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Celso Menezes Filho, Andre Messias, Paulo Henrique F Silva, and Rosalia Antunes-Foschini
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amblyopia ,cataract surgery ,congenital cataract ,myopic shift ,strabismus ,Ophthalmology ,RE1-994 - Abstract
Purpose: To investigate predictors for myopic shift after pediatric cataract surgery after at least 3 years follow-up. Study Design: Cross-sectional and retrospective study. Methods: This study included patients treated for congenital or infantile cataract operated up to 5 years of age between 2010 and 2017. Patients were recruited for ophthalmologic evaluation. Surgical and medical data were acquired in medical charts. Statistical Analysis: Univariate and multivariate regressions were performed to look for potential risk factors for myopic shift. Results: This study evaluated 81 eyes of 50 patients, with 62 (77%) being bilateral cases, 48 (59%) with intraocular lens implantation, and 37 (74%) patients being strabismic. Age at surgery was 7.7 (3.7–30.5) months and at evaluation was 93.5 (55.1–113.0) months. Total myopic shift was -4.32 ± 3.25 D, significantly greater in patients operated on up to 6 months of life (-5.73 ± 3.14 D). The distant best-corrected visual acuity (BCVA) was 0.6 (0.3–1.0) log of minimum angle of resolution (logMAR). Regarding myopic shift, in univariate analysis, older age at surgery is a protective factor (+0.08 D for each month older, P = 0.001). The presence of strabismus (-2.52 D, P = 0.014), aphakia (-2.45 D, P = 0.006), distant BCVA (-0.15 D per 0.1 logMAR, P = 0.024), and surgical complications (-3.02 D, P = 0.001) are risk factors. In multivariate analysis, older age at surgery (+0.06 D, P = 0.012) and surgical complications (-2.52 D, P = 0.001) remain significant. Conclusion: In pediatric cataract surgery, myopic shift is greater when surgery is performed in a younger age and if associated with surgical complications.
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- 2024
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10. ANÁLISE DE MANIFESTAÇÕES PATOLOGICAS EM PATRIMÔNIO HISTÓRICO: UM ESTUDO DE CASO
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Ana Jesus, André Messias, Valney Silva, and Andro Farias
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- 2020
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11. Tabelas para medir acuidade visual com escala logarítmica: porque usar e como construir Logarithmic visual acuity charts: reasons to use and how to design it
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André Messias, Rodrigo Jorge, and Antonio Augusto Velasco e Cruz
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Visual acuity ,lcsh:Ophthalmology ,lcsh:RE1-994 ,Acuidade visual ,Optometria ,Optometry - Abstract
A acuidade visual representa o inverso do ângulo visual, ou seja, da menor distância angular entre dois pontos que podem ser vistos como separados. Apesar de ser a medida da função visual mais comum na prática oftalmológica, é muitas vezes interpretada erroneamente, principalmente devido às inúmeras tabelas e diferentes sistemas de notações empregados na clínica. Este artigo revisa alguns conceitos sobre a quantificação da acuidade visual, suas principais notações e tabelas de medida, discutindo as vantagens do uso da escala logarítmica.Visual acuity represents the visual angle or the smallest distance between two points that allows their discrimination as separated points. Although it is the most common clinical measurement of visual function, it is often misunderstood, especially due to the variety of charts and different notation systems employed for its quantification. This article reviews some concepts about visual acuity measurement, the main notation systems, type of charts and discuss the advantages of using logarithmic scales.
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- 2010
12. Textos padronizados em português (BR) para medida da velocidade de leitura: comparação com quatro idiomas europeus New standardized texts in Brazilian Portuguese to assess reading speed: comparison with four European languages
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André Messias, Antonio Augusto Velasco e Cruz, Sonia Jecov Schallenmüller, and Susanne Trauzettel-Klosinski
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Visual acuity ,Campos visuais ,Mental processes ,Vision tests ,Movimentos oculares ,Fixação ocular ,Vocabulary ,lcsh:Ophthalmology ,Fixation, ocular ,Translations ,Cross-cultural comparison ,Comparação transcultural ,Vocabulário ,Lingüística ,Acuidade visual ,Vision, low ,Linguistics ,Processos mentais ,Tradução (produto) ,Baixa visão ,Eye movements ,Testes visuais ,Reading ,Leitura ,lcsh:RE1-994 ,Visual fields - Abstract
OBJETIVO: Desenvolver textos para medida da velocidade de leitura comparáveis com outros quatro idiomas europeus. MÉTODOS: Dez textos com similar grau de dificuldade, número de caracteres, número de palavras e sintaxe (segundo a teoria de Gibson) foram desenvolvidos por um especialista em lingüística, em português (BR), fazendo-se a tradução de textos previamente padronizados em quatro idiomas: inglês, francês, finlandês e alemão. A velocidade de leitura foi medida em 25 indivíduos saudáveis de idade entre 19 e 35 anos (mediana=24 anos) com os dez textos. RESULTADOS: A velocidade de leitura nos textos em português foi em média 1100 ± 167 (desvio padrão) caracteres por minuto. Pequenas diferenças foram encontradas entre as velocidades de leitura medidas com os dez textos, e essas diferenças não foram estatisticamente significantes em grupos de no mínimo seis textos. A velocidade de leitura dos voluntários da mesma faixa etária nos outros idiomas foi: alemão: 1126 ± 105; finlandês: 1263 ± 142; francês: 1214 ± 152 e inglês: 1234 ± 147. CONCLUSÃO: Os autores desenvolveram um conjunto de textos em português (BR) padronizados e homogêneos para medida da velocidade de leitura, que são comparáveis com textos em outros quatro idiomas europeus. Esses textos podem ser usados para estudos multicêntricos internacionais envolvendo leitura e visão subnormal.PURPOSE: To develop standardized texts in Brazilian Portuguese to assess reading speed and compare performances among four European languages. METHODS: 10 texts were designed by a linguistic expert at the level of a sixth grade reading material (reading ages 10-12 years) and were matched for length and syntactic complexity, according to the syntactic prediction locality theory of Gibson. Normally sighted native speaking volunteers aged 18-35 years read each text aloud at random. RESULTS: The reading speed was on average 1100 ± 167 (standard deviation) characters per minute. Only small differences were found between the measured reading speeds of the 10 texts, and these differences were not statistically significant in groups of at least 6 texts. The mean reading speed in age-matched volunteers in Finnish was: 1263 ± 142; French: 1214 ± 152; English: 1234 ± 147; and German: 1126 ± 105. CONCLUSIONS: The authors developed a set of standardized, homogeneous, and comparable texts in Brazilian Portuguese. These texts will be a valuable tool to measure reading speed for repeated measurements and in international studies in the field of reading and low vision research.
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- 2008
13. Estudo da produção em escala aumentada de nanopartículas de dissulfeto de molibdênio (2H-MoS2) pelo método hidrotérmico
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Teixeira, André Messias, Universidade Federal de Santa Catarina, Drago, Valderes, and Mello, José Daniel Biasoli de
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Tribologia ,Emulsões ,Engenharia de materiais ,Nanopartículas ,Ciencia dos materiais ,Dissulfeto de molibdênio - Abstract
Dissertação (Mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Ciência e Engenharia de Materiais, Florianópolis, 2012 No presente trabalho foi desenvolvido um método de produção em escala aumentada de nanopartículas de dissulfeto de molibdênio (MoS2). Foi utilizada a rota hidrotérmica para sua produção, sendo projetado um forno de aquecimento resistivo com capacidade para 9 autoclaves. Estas foram confeccionadas em aço SAE 310, revestidas internamente com politetrafluoretileno (PTFE), tendo 120 ml de volume interno cada. Este forno conta com um assoalho vibratório capaz de manter as autoclaves sob agitação constante, alcançando até dois modos vibracionais fundamentais do conteúdo líquido no interior delas. As sínteses foram desenvolvidas na temperatura de 220°C em períodos de 6, 12 e 24 horas, tendo como reagentes o molibdato de amônio tetrahidratado, hidroxilamina cloridrato e tioureia, sendo a reação dada em água bidestilada. As amostras foram caracterizadas quanto ao seu rendimento químico, estrutura cristalina por Difração de Raios X (DRX), morfologia por Microscopia Eletrônica de Varredura por Emissão de Campo (FEG), Termogravimetria e Infravermelho por Transformada de Fourier (TG-IR) simultaneamente, Espectroscopia Raman, Interferometria Óptica e, com enfoque maior, Tribologia. Foram obtidas nanopartículas na morfologia de nanoflores com cerca de 200 nm de diâmetro com estrutura cristalina hexagonal lamelar (2H-MoS2) parcialmente amorfizadas. Estas formam dispersões relativamente estáveis com os três óleos sintéticos testados (fortemente polar, de média polaridade e apolar) e com água bidestilada. Obteve-se um rendimento médio de reação de 71,3% em relação ao Mo e foi verificado um aumento de 10% neste quando comparado com amostras estáticas, sem a aplicação da agitação por vibração. Desta forma, valores para uma produção industrial utilizando o sistema desenvolvido ficam em torno de 300 g/mês. Abstract : In the present work was developed a method for scaling up the production of molybdenum disulfide (MoS2) nanoparticles. It was used a hydrothermal route to its production, being designed a resistive heating furnace with capacity for 9 autoclaves. They were designed in SAE 310 stainless steel, internally coated with polytetrafluoroethylene (PTFE), having 120 ml internal volume each. This furnace has a vibratory floor capable of maintaining the autoclaves under stirring, reaching until two fundamental vibrational modes of the liquid contents inside them. The syntheses were developed at temperature of 220 °C in periods of 6, 12 and 24 hours, with the reagents of ammonium molybdate tetrahydrate, hydroxylamine hydrochloride and thiourea, the reaction is given in bidistilled water. The samples were characterized according to their chemical yield, crystalline structure by X-ray Diffraction (XRD), morphology by Field Emission Scanning Electron Microscopy (FEG), Thermogravimetry and Fourier Transform Infrared (TG-IR) simultaneously, Raman Spectroscopy, Optical Interferometry and, with increased focus, Tribology. Nanoparticles were obtained on the morphology of nanoflowers about 200 nm diameter with lamellar hexagonal crystalline structure (2H-MoS2) partially amorphous. These form relatively stable dispersions with the three synthetic oils tested (strongly polar, medium polarity and nonpolar) and with bidistilled water. It was obtained an average reaction yield of 71.3% in relation to Mo and there was verified an increment of 10% in it in comparison with static samples, without the application of stirring by vibration. Thus, values for an industrial production using the developed system are around 300 g / month.
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- 2012
14. Avaliação da dinâmica da marcha em ratos submetidos à isquemia de membro
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Marcelo Belini Dalio, Matheus Bredarioli, William Alves do Prado, Edwaldo Edner Joviliano, Carlos Eli Piccinato, Antônio Carlos de Sousa, and André Messias
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Male ,Traumatismo por Reperfusão ,medicine.medical_specialty ,Claudicação Intermitente ,Hindlimb ,Iliac Artery ,Peripheral Arterial Disease ,Ischemia ,Left hindlimb ,medicine ,Animals ,Rats, Wistar ,Treadmill ,Gait ,Ratos ,business.industry ,Intermittent Claudication ,medicine.disease ,Limb ischemia ,Intermittent claudication ,Surgery ,Rats ,Anesthesia ,Reperfusion Injury ,Doença Arterial Periférica ,medicine.symptom ,business ,Ligation ,Reperfusion injury - Abstract
PURPOSE: To describe a method for the assessment of gait dynamics in rats submitted to limb ischemia. METHODS: Twenty-four male Wistar rats (150-160g) were used. Twelve animals were submitted to limb ischemia by ligation of the common left iliac artery (ischemic group: n = 12); and a sham-operated group was used as control (n=12). After a recovery period of 6 weeks, gait dynamics was assessed by counting the complete footprints and the number of hindlimb-floor contacts during a treadmill test for five minutes at a speed of 12 m.min-1 and angulation of 15°. The number of contacts of the left hindlimb was divided by the right hindlimb values (LRR) for group comparisons. Ischemic disability was quantified by comparing the area under curve (AUC) created by plotting each contact versus time for each hindlimb. The left hindlimb ischemic disability index (LHDI), which was compared between groups, was defined by the formula: LHDI = (1- AUC left / AUC right) x 100. RESULTS: Surgery was well tolerated by all animals. Rats did not suffer tissue loss or ulcerations. Complete footprint LRR was 0.3 ± 0.08 for the ischemic group and 1.3 ± 0.9 for controls (p=0.0043). Number of contacts LLR was 0.5 ± 0.2 for the ischemic group and 1.0 ± 0.1 for the control group (p=0.0051). LHDI was 56.83 ± 10.67 for the ischemic group and 2.50 ± 13.10 for the control group (P = 0.031). CONCLUSION: Assessment of gait dynamics in rats submitted to limb ischemia could be done by footprint analysis and hindlimb contact recording during a treadmill test. OBJETIVO: Descrever um método para avaliar a dinâmica da marcha em ratos submetidos à isquemia de membro pélvico. MÉTODOS: Vinte e quatro ratos Wistar machos (150-160g) foram utilizados neste estudo experimental. Doze animais foram submetidos à isquemia de membro pélvico por meio da ligadura da artéria ilíaca comum esquerda (grupo isquêmico: n=12); e doze animais foram submetidos à cirurgia simulada e usados como controle (grupo controle: n=12). Após seis semanas de recuperação, foi realizada avaliação da dinâmica da marcha por meio da contagem de impressões plantares e da contagem de contatos pata-solo durante teste com esteira durante cinco minutos, velocidade 12 m.min-1 e angulação de 15°. Os valores do número de contatos do membro pélvico esquerdo foram divididos pelos do membro pélvico direito (razão esquerda-direita - LRR) para comparação entre os grupos. A quantificação da incapacitação isquêmica foi feita comparando a área sob a curva (AUC) da representação gráfica dos contatos versus tempo para cada membro pélvico. O índice de incapacitação isquêmica do membro pélvico esquerdo (LHDI), que foi comparado entre os grupos, foi definido pela fórmula: LHDI = (1- AUC esquerda / AUC direito) x 100. RESULTADOS: A cirurgia foi bem tolerada por todos os animais. Nenhum rato apresentou necrose tecidual ou ulceração. A LRR das impressões plantares completas foi 0,3 ± 0,08 no grupo isquêmico e 1,3 ± 0,9 no grupo controle (p=0,0043). A LRR do número de contatos foi 0,5 ± 0,2 no grupo isquêmico e 1,0 ± 0,1 no grupo controle (p=0,0051). O LHDI foi 56,83 ± 10,67 no grupo isquêmico e 2,50 ± 13,10 no grupo controle (p=0,031). CONCLUSÃO: Avaliação da dinâmica da marcha em ratos submetidos à isquemia de membro pélvico pôde ser feita por meio da contagem de impressões plantares e da contagem de contatos pata-solo durante teste com esteira.
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- 2011
15. [Logarithmic visual acuity charts: reasons to use and how to design it]
- Author
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André, Messias, Rodrigo, Jorge, and Antonio Augusto Velasco e, Cruz
- Subjects
Visual Acuity ,Humans ,Algorithms ,Optometry - Abstract
Visual acuity represents the visual angle or the smallest distance between two points that allows their discrimination as separated points. Although it is the most common clinical measurement of visual function, it is often misunderstood, especially due to the variety of charts and different notation systems employed for its quantification. This article reviews some concepts about visual acuity measurement, the main notation systems, type of charts and discuss the advantages of using logarithmic scales.
- Published
- 2009
16. [New standardized texts in Brazilian Portuguese to assess reading speed--comparison with four European languages]
- Author
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André, Messias, Antonio Augusto, Velasco e Cruz, Sonia Jecov, Schallenmüller, and Susanne, Trauzettel-Klosinski
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Adult ,Cross-Cultural Comparison ,Male ,Vision Tests ,Visual Acuity ,Reproducibility of Results ,Linguistics ,Europe ,Young Adult ,Reading ,Data Interpretation, Statistical ,Humans ,Female ,Translations ,Brazil ,Language - Abstract
To develop standardized texts in Brazilian Portuguese to assess reading speed and compare performances among four European languages.10 texts were designed by a linguistic expert at the level of a sixth grade reading material (reading ages 10-12 years) and were matched for length and syntactic complexity, according to the syntactic prediction locality theory of Gibson. Normally sighted native speaking volunteers aged 18-35 years read each text aloud at random.The reading speed was on average 1100 +/- 167 (standard deviation) characters per minute. Only small differences were found between the measured reading speeds of the 10 texts, and these differences were not statistically significant in groups of at least 6 texts. The mean reading speed in age-matched volunteers in Finnish was: 1263 +/- 142; French: 1214 +/- 152; English: 1234 +/- 147; and German: 1126 +/- 105.The authors developed a set of standardized, homogeneous, and comparable texts in Brazilian Portuguese. These texts will be a valuable tool to measure reading speed for repeated measurements and in international studies in the field of reading and low vision research.
- Published
- 2007
17. Costs and outcomes of phacoemulsification for cataracts performed by residents
- Author
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Roberto, Saad Filho, Renata, Moreto, Ricardo Okada, Nakaghi, William, Haddad, Roberto Pinto, Coelho, and André, Messias
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Health care and cost analysis ,Lens, crystalline/surgery ,Phacoemulsification ,genetic structures ,Visual Acuity ,lens, crystalline/surgery ,Cataract ,eye diseases ,Postoperative Complications ,lcsh:Ophthalmology ,cataract extraction/economics ,lcsh:RE1-994 ,phacoemulsification ,treatment outcome ,Humans ,Cataract extraction/economics ,sense organs ,Treatment outcome ,Intraoperative Complications ,health care and cost analysis ,Retrospective Studies - Abstract
Purpose: To describe costs and outcomes of phacoemulsification for cataracts performed by ophthalmology residents. Methods: We obtained medical records from patients operated on in 2011 by third year residents (R3) using phacoemulsification (n=576). Our expenses estimation included professionals’ and hospital costs (fees, materials, medications, and equipment). The study outcomes included spectacle-corrected visual acuities before and six months after the operation, rate of intraoperative complications, and total number of postoperative visits. We compared outcome variables with those from extracapsular cataract extraction procedures (n=274) performed by R3 residents in 1997. Results: The mean total cost for phacoemulsification was US$ 416, while an overall estimation indicated the extracapsular cataract extraction cost at US$ 284 (as of December 30, 2011). The mean preoperative spectacle-corrected visual acuity was worse for eyes scheduled for extracapsular cataract extraction (1.73 ± 0.62), than for eyes scheduled for phacoemulsification (0.74 ± 0.54 logMAR) (p
18. Quantification of optic disc edema during exposure to high altitude shows no correlation to acute mountain sickness.
- Author
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Gabriel Willmann, M Dominik Fischer, Andreas Schatz, Kai Schommer, Andre Messias, Eberhart Zrenner, Karl U Bartz-Schmidt, and Florian Gekeler
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Medicine ,Science - Abstract
BACKGROUND: The study aimed to quantify changes of the optic nerve head (ONH) during exposure to high altitude and to assess a correlation with acute mountain sickness (AMS). This work is related to the Tuebingen High Altitude Ophthalmology (THAO) study. METHODOLOGY/PRINCIPAL FINDINGS: A confocal scanning laser ophthalmoscope (cSLO, Heidelberg Retina Tomograph, HRT3®) was used to quantify changes at the ONH in 18 healthy participants before, during and after rapid ascent to high altitude (4559 m). Slitlamp biomicroscopy was used for clinical optic disc evaluation; AMS was assessed with Lake Louise (LL) and AMS-cerebral (AMS-c) scores; oxygen saturation (SpO₂) and heart rate (HR) were monitored. These parameters were used to correlate with changes at the ONH. After the first night spent at high altitude, incidence of AMS was 55% and presence of clinical optic disc edema (ODE) 79%. Key stereometric parameters of the HRT3® used to describe ODE (mean retinal nerve fiber layer [RNFL] thickness, RNFL cross sectional area, optic disc rim volume and maximum contour elevation) changed significantly at high altitude compared to baseline (p
- Published
- 2011
- Full Text
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