RESUMO
Tears are an important component of the ocular surface protection mechanism and are in close contact with the corneal epithelium and the environment. Their composition is well-known in humans; however, there are few investigations on the composition and function of tears in reptiles, birds and others mammals, which would elucidate the mechanisms governing the maintenance of ocular homeostasis. In this work, electrophoretic profiles and an evaluation of total protein, albumin, urea, glucose, and cholesterol concentrations in tears of semi-aquatic, terrestrial, and marine reptiles (Caiman latirostris, Chelonia mydas, Caretta caretta, Eretmochelys imbricata, Lepidochelys olivacea, and Chelonoidis carbonaria), birds (Tyto furcata, Rupornis magnirostris and Ara ararauna), and mammals (Equus caballus and Canis lupus familiaris) were apresented. Human tear components and respective blood serum samples were used as references. The electrophoretic analysis revealed similarities whithin same Classes. The results of the tear-blood serum relationship and the comparison to human tear components showed particularities that are potentially derived from a homeostatic response to the environment. When the tear compositions of animals belonging to different ecological clusters were compared, marked differences were observed in total protein and urea concentrations. Thus, reptile, bird, and mammalian tears are complex fluids with differing concentrations of biochemical components that are potentially a result of the animals' adaptation to different environments.
RESUMO
OBJECTIVE: The present study aims to describe ocular alterations in sickle cell disease patients in Bahia, a Northeast state, with the highest prevalence of the disease in Brazil. METHODS: We carried out a cross-sectional study in a group of 146 (292 eyes) sickle cell disease patients (90 HBSS and 56 HBSC). Ophthalmologic examination including indirect binocular ophthalmoscopy was performed. Examination was completed by fluorescein angiography to detect retinal lesions. RESULTS: The most frequent ocular lesions identified were "vascular tortuosity" and "black sunburst". Proliferative retinopathy was found in 22 (12.2 percent) eyes of HBSS patients and 25 (22.3 percent) eyes of HBSC patients (OR=2.06; CI95 percent: 1.5-4.06, p=0.022); Its frequency was higher among HBSS patients aged 20-39 years, while in HBSC patients, it peaked after 40 years (35.7 percent and 42.8 percent) and dropped sharply afterwards. CONCLUSION: Proliferative retinopathy was described as early as 10 years of age in both patients groups. Proliferative sickle retinopathy can result in blindness and the knowledge of the most prevalent ocular alterations and age risk will be important to establish a protocol of ophthalmologic follow-up, in order to prevent a severe visual loss and increase patient's life quality.
OBJETIVO: O presente estudo teve como objetivo descrever as alterações oculares em pacientes portadores de doença falciforme, na Bahia, um estado do Nordeste, que tem a maior prevalência da doença no Brasil. MÉTODOS: Nós conduzimos um estudo de corte transversal em um grupo de 146 (292 olhos) pacientes com Doença Falciforme (90 HBSS e 56 HBSC). Para exame oftalmológico foi realizada oftalmoscopia binocular indireta complementada pela retinografia fluorescente para detecção de lesões retinianas decorrentes da Doença Falciforme. RESULTADOS: As lesões mais frequentemente encontradas foram o aumento da tortuosidade vascular e "black sumburst" Retinopatia proliferativa foi encontrada em 22 (12,2 por cento) olhos de pacientes HBSS e 25 (22,3 por cento) olhos de pacientes HBSC (OR=2.06; CI95 por cento: 1.5-4.06, p=0. 022); essa frequência foi maior entre os pacientes HBSS com idade entre 20 - 39 anos, enquanto que nos pacientes HBSC foi maior nos acima de 40 anos (35.7 por cento e 42.8 por cento), decaindo abruptamente após essa idade. CONCLUSÃO: Retinopatia proliferativa foi descrita por volta dos dez anos de idade em ambos os grupos. A prevalência da retinopatia falciforme proliferativa pode resultar em cegueira e o conhecimento das alterações oculares mais prevalentes e idade de risco destas em pacientes com Doença Falciforme será importante para estabelecer um protocolo de acompanhamento oftalmológico, para prevenir um dano visual clinicamente grave, aumentando a qualidade de vida destes pacientes.