3,568 research outputs found

    Macular Microcysts in Mitochondrial Optic Neuropathies: Prevalence and Retinal Layer Thickness Measurements.

    Get PDF
    PurposeTo investigate the thickness of the retinal layers and to assess the prevalence of macular microcysts (MM) in the inner nuclear layer (INL) of patients with mitochondrial optic neuropathies (MON).MethodsAll patients with molecularly confirmed MON, i.e. Leber's Hereditary Optic Neuropathy (LHON) and Dominant Optic Atrophy (DOA), referred between 2010 and 2012 were enrolled. Eight patients with MM were compared with two control groups: MON patients without MM matched by age, peripapillary retinal nerve fiber layer (RNFL) thickness, and visual acuity, as well as age-matched controls. Retinal segmentation was performed using specific Optical coherence tomography (OCT) software (Carl Zeiss Meditec). Macular segmentation thickness values of the three groups were compared by one-way analysis of variance with Bonferroni post hoc corrections.ResultsMM were identified in 5/90 (5.6%) patients with LHON and 3/58 (5.2%) with DOA. The INL was thicker in patients with MON compared to controls regardless of the presence of MM [133.1±7μm vs 122.3±9μm in MM patients (p<0.01) and 128.5±8μm vs. 122.3±9μm in no-MM patients (p<0.05)], however the outer nuclear layer (ONL) was thicker in patients with MM (101.4±1mμ) compared to patients without MM [77.5±8mμ (p<0.001)] and controls [78.4±7mμ (p<0.001)]. ONL thickness did not significantly differ between patients without MM and controls.ConclusionThe prevalence of MM in MON is low (5-6%), but associated with ONL thickening. We speculate that in MON patients with MM, vitreo-retinal traction contributes to the thickening of ONL as well as to the production of cystic spaces

    Paleobiología de la conservación : sumando la ecología del pasado para comprender el presente

    Get PDF
    El cambio climático global está modificando de modo acelerado las características de los hábitats, y eso tiene un impacto sobre las comunidades que ya se encuentran alteradas por impactos antrópicos anteriores. ¿Cómo eran las comunidades no impactadas? Las únicas evidencias que tenemos están alojadas en los restos de los organismos, hallados sobre la superficie o en los primeros centímetros debajo del sedimento, en registros históricos y sitios arqueológicos. ¿Cómo serán esas comunidades en la nueva configuración climática? La paleontología tiene un amplio registro de las respuestas de las comunidades a los cambios ambientales, que pueden utilizarse como modelos para el diseño de planes de conservación de la biodiversidad. ¿Estamos en medio de una extinción en masa? La paleontología puede aportar significativamente a contestar esta pregunta, a partir del conocimiento de los fenómenos relacionados con las cinco extinciones masivas, y de otras de menor escala, registradas en los sedimentos y rocas pretéritos. La paleobiología de la conservación tiene el objetivo de contribuir a los proyectos de conservación con la información proveniente del registro de la vida en el pasado

    Foresight, cognition, and long-term performance : insights from the automotive industry and opportunities for future research

    Get PDF
    We explore the relationship between foresight and managerial cognition and the contribution of foresight to the long‐term performance of organizations facing major sources of uncertainty. Our research setting is the automotive industry, a compelling research setting for illustrating and reflecting upon the role of foresight in strategic decision making, as the industry is currently experiencing major drivers of change and technological discontinuities. We carefully examined the most recent empirical and theoretical works in the field of foresight, by conducting a thorough literature review. We found that scholars and practitioners increasingly emphasize the ability of foresight to change the mental models of senior managers and the role of such ability in the long‐term adaptation to external changes. Overall, our study contributes to the development of a programmatic stream of research in the domain of foresight and future studies

    Acometimento pancreático em casos fatais de leptospirose humana: aspectos clínicos e histopatológicos

    Get PDF
    Hyperamylasemia has been reported in more than 65% of patients with severe leptospirosis, and the true diagnosis of acute pancreatitis is complicated by the fact that renal failure can increase serum amylase levels. Based on these data we retrospectively analyzed the clinical and histopathological features of pancreas involvement in 13 cases of fatal human leptospirosis. The most common signs and symptoms presented at admission were fever, chills, vomiting, myalgia, dehydratation, abdominal pain and diarrhea. Trombocytopenia was evident in 11 patients. Mild increased of AST and ALT levels was seen in 9 patients. Hyperamylasemia was recorded in every patient in whom it was measured, with values above 180 IU/L (3 cases). All patients presented acute renal failure and five have been submitted to dialytic treatment. The main cause of death was acute respiratory failure due to pulmonary hemorrhage. Pancreas fragments were collected for histological study and fat necrosis was the criterion used to classify acute pancreatitis. Histological pancreatic findings were edema, mild inflammatory infiltrate of lymphocytes, hemorrhage, congestion, fat necrosis and calcification. All the patients infected with severe form of leptospirosis who develop abdominal pain should raise the suspect of pancreatic involvement.Hiperamilasemia tem sido documentada em mais de 65% dos pacientes com leptospirose severa, e o diagnóstico de pancreatite aguda torna-se difícil pelo fato de que a insuficiência renal pode aumentar os níveis séricos de amilase. Assim, foram analisadas, retrospectivamente, as características clínicas e histopatológicas do acometimento pancreático em 13 casos fatais de leptospirose humana. Os sinais e sintomas mais comuns foram febre, calafrios, vômitos, mialgia, desidratação, dor abdominal e diarréia. Trombocitopenia foi encontrada em 11 pacientes. Elevação dos níveis de AST e ALT foi observada em nove casos. Hiperamilasemia foi detectada em todos os pacientes em que foi dosada, com valores acima de 180 UI/L (três casos). Todos os pacientes desenvolveram insuficiência renal aguda e cinco necessitaram de tratamento dialítico. A principal causa de morte foi insuficiência respiratória devido à hemorragia pulmonar. Fragmentos do pâncreas foram obtidos para estudo histológico, e necrose gordurosa foi o critério utilizado para classificar pancreatite. Os achados histológicos foram edema pancreático, infiltrado inflamatório discreto de linfócitos, hemorragia, congestão, necrose gordurosa e calcificação. Deve-se suspeitar de acometimento pancreático em todo paciente com a forma grave de leptospirose que desenvolve dor abdominal

    Erythema induratum of Bazin and renal tuberculosis: report of an association

    Get PDF
    Erythema induratum of Bazin is a disease that usually affects women, in whom erythematous subcutaneous nodules and plaques appear on the posterior part of the lower extremities, some of which ulcerate. In many countries, tuberculosis is still the main etiologic factor. We report a case of a 40-year-old woman who presented a course of protracted and recurrent episodes over five years of cutaneous lesions on her legs. These tend to involute, but new crops appear at irregular intervals. It was painful, erythematous-violaceous nodules, some of which drained a reddish secretion. The histopathologic features of the lesions demonstrated inflammatory infiltration, with predominance of neutrophils in dermis and hypodermis, necrotizing vasculitis in the arterioles and septal fibrosis. There was no granuloma. The Ziehl-Neelsen stain did not revealed acid-fast bacilli, and the culture of biopsy specimen was negative. The tuberculin skin test was strongly positive (17 mm). The chest X-ray was normal. Few months later she presented adynamia and urinary complaints, such as polacyuria and dysuria. It has been done an urynalysis, which demonstrated acid pH urine, sterile pyuria and microscopic hematuria. It was then raised the diagnostic hypothesis of renal tuberculosis. The urine culture for M. tuberculosis was positive in two out of ten samples. The treatment was instituted with rifampin, isoniazid and pyrazinamide, with complete regression. This case illustrates a clear association between erythema induratum and renal tuberculosis, demonstrated by the remission of the cutaneous lesions after the treatment of the renal tuberculosis.O eritema indurado de Bazin é doença caracterizada por erupções cutâneas que usualmente ocorrem nos membros inferiores de mulheres adolescentes e de meia idade. Relatamos o caso de paciente de 40 anos que apresentava há 5 anos lesões cutâneas em região inferior de ambas as pernas. Tratavam-se de nódulos eritemato-violáceos, dolorosos, alguns dos quais drenavam secreção serossangüínea. O exame histopatológico da biópsia de pele demonstrou infiltrado inflamatório, com predomínio de neutrófilos na derme e hipoderme, vasculite necrosante em arteríolas e fibrose septal. Não foram identificados granulomas. A coloração de Ziehl-Neelsen não revelou bacilos álcool-ácido resistentes, e a cultura do material biopsiado foi negativa. O PPD foi fortemente reator (17 mm). O raio-X de tórax era normal. Alguns meses depois, a paciente evoluiu com adinamia e sintomas urinários, como polaciúria e disúria. O exame de urina mostrou urina ácida, piúria estéril e hematúria. Foi levantada a hipótese de tuberculose renal. A urinocultura foi positiva para M. tuberculosis em duas amostras de dez solicitadas. O tratamento foi instituído com rifampicina, isoniazida e pirazinamida, com melhora considerável do quadro. Este caso ilustra uma associação clara entre o eritema indurado e a tuberculose renal, demonstrada através da remissão das lesões cutâneas após o tratamento da tuberculose renal

    Renal involvement in human rabies: clinical manifestations and autopsy findings of nine cases from northeast of Brazil

    Get PDF
    A retrospective study was conducted in nine patients with rabies admitted to a hospital of Fortaleza, Brazil. Autopsy was performed in all cases. The ages ranged from three to 81 years and six were males. They all were bitten by dogs. The time between the accident and the hospital admission ranged from 20 to 120 days (mean 45 ± 34 days). The time until death ranged from one to nine days (mean 3.3 ± 5.5 days). The signs and symptoms presented were fever, hydrophobia, aerophobia, agitation, disorientation, dyspnea, sialorrhea, vomiting, oliguria, sore throat, pain and hypoesthesia in the site of the bite, headache, syncope, cough, hematemesis, mydriasis, hematuria, constipation, cervical pain and priapism. In three out of six patients, there was evidence of acute renal failure, defined as serum creatinine >; 1.4 mg/dL. The post-mortem findings in the kidneys were mild to moderate glomerular congestion and mild to intense peritubular capillary congestion. Acute tubular necrosis was seen in only two cases. This study shows some evidence of renal involvement in rabies. Histopathologic findings are nonspecific, so hemodynamic instability, caused by autonomic dysfunction, hydrophobia and dehydration must be responsible for acute renal failure in rabies.Foi realizado estudo retrospectivo de nove casos de raiva internados em um hospital de Fortaleza, Brasil. Autópsia foi realizada em todos os casos. As idades variaram de 3 a 81 anos. Todos foram agredidos por cães. O tempo entre o acidente e a admissão hospitalar variou de 20 a 120 dias (média de 45 ± 34 dias). O tempo de internamento variou de 1 a 9 dias (média de 5.5 ± 3.1 dias). Os sinais e sintomas observados foram febre, hidrofobia, aerofobia, agitação, desorientação, dispnéia, sialorréia, vômitos, oligúria, faringite, dor e hipoestesia no local da mordida, cefaléia, síncope, tosse, hematêmese, midríase, hematúria, constipação, dor cervical e priapismo. Em três de seis pacientes (50%) foi encontrada evidência de insuficiência renal aguda, definida como creatinina >; 1.4 mg/dL. Os achados de autópsia do tecido renal foram congestão glomerular leve a moderada e congestão capilar peritubular leve a intensa. Necrose tubular aguda foi encontrada em dois casos. Estes achados são inespecíficos, de modo que a instabilidade hemodinâmica, causada por disfunção autonômica, hidrofobia e desidratação podem ser considerados como responsáveis pela insuficiência renal aguda na raiva

    Novos Materiais Dosimétricos para Aplicações em Física Médica

    Get PDF
    Este artigo apresenta o estado da arte dos materiais dosimétricos para aplicações em dosimetria pessoal e clínica. O objetivo é fornecer uma visão geral das vantagens e limitações dos dosímetros comerciais disponíveis mais usados, bem como novos materiais estudados na atualidade. Resumimos trabalhos recentes publicados sobre materiais cristalinos e vítreos mais discutidos e com melhores perspectivas para uso prático em dosimetria por Termoluminescência (TL), Luminescência Opticamente Estimulada (OSL), Radiofotoluminescência (RPL) e Ressonância de Spin Eletrônico (ESR), e ainda géis, dosímetros plásticos e emulsões superaquecidas. São tratadas novas formas de uso desses materiais, como fibras para dosimetria ativa, filmes dosimétricos para dosimetria 2D, e materiais que possam ser usados em dosimetria tridimensional. Os trabalhos atuais demonstram uma clara tendência da opção do uso cada vez maior de optoeletrônica para obtenção dos sinais e sua leitura

    Acute kidney injury and pancreatitis due to scorpion sting: case report and literature review

    Get PDF
    Despite the high number of accidents due to scorpion stings in Brazil, severe cases in adults are seldomly reported. In the Northeast region of Brazil, Tityus stigmurus is the most prevalent species. A 69 year-old woman who was stung by a scorpion attended the emergency room 5 hours after envenomation. She got worse due to abdominal pain. Clinical findings were concordant with class III scorpion envenomation (major systemic manifestations), complicated by acute kidney injury and acute pancreatitis. Intensive supportive therapy was adopted. In the follow-up, 3 months later, she was completely recovered. This report is being brought to recommend the thorough management of victims of scorpion accidents, enabling early diagnosis of severe complications, which could lead to death if aggressive supportive measures are not early and adequately taken
    corecore