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RESUMO Objetivo: Avaliar o filme lacrimal e os sintomas de olho seco antes e após a realização da facoemulsificação. Métodos: Participaram deste estudo clínico 51 pacientes diagnosticados com catarata (55% mulheres; 78% brancos; 71,2 ± 6,5 anos de idade; sem uso de colírio lubrificante) que foram submetidos à facoemulsificação em um hospital na cidade de Aparecida (SP). A análise do filme lacrimal foi feita pelo teste de ruptura do filme lacrimal, e os sintomas de olho seco foram avaliados pelo Índice de Doença da Superfície Ocular, ambos antes da cirurgia e 30 e 60 dias de pós-operatório. Resultados: Na análise pré-operatória, 25,5% dos pacientes tinham olho seco pelo critério subjetivo (Índice de Doença da Superfície Ocular ≥ 25%), enquanto a proporção de pacientes com olho seco foi de 92,2% pelo critério objetivo (teste de ruptura do filme lacrimal < 10 segundos). Não houve correlação entre o teste de ruptura do filme lacrimal e o Índice de Doença da Superfície Ocular (r = −0,14; p = 0,33). Não foi observada redução dos sintomas de olho seco (15,9 ± 17,6 versus 12,2 ± 13,2 versus 7,8 ± 11,5; p < 0,001) e nem do tempo de ruptura do filme lacrimal (6,2 ± 2,2 vs. 4,3 ± 2,0 versus 6,9 ± 2,0 segundos; p < 0,001) no pré, 30 e 60 dias após a cirurgia. Conclusão: A facoemulsificação desencadeia sintomas de olho seco e altera os valores do teste de ruptura do filme lacrimal e do Índice de Doença da Superfície Ocular, havendo melhora depois da cirurgia, com o passar dos dias. Observou-se que, após os 60 dias, os sintomas de olho seco avaliados pelo Índice de Doença da Superfície Ocular apresentaram melhora. Em relação ao filme lacrimal, avaliado pelo teste de ruptura do filme lacrimal, observou-se que houve piora estatisticamente significativa aos 30 dias, seguida de melhora no pós-operatório de 60 dias. Os resultados sugerem que a análise clínica do olho seco deve ser realizada por diferentes métodos, preferencialmente objetivos.

ABSTRACT Objective: To evaluate the tear film and dry eye symptoms before and after phacoemulsification. Methods: Fifty-one patients diagnosed with cataracts participated in this clinical study (55% female; 78% white; 71.2 ± 6.5 years old; without the use of lubricating eye drops) and underwent phacoemulsification at a hospital in Aparecida (SP). Tear film analysis was performed by the tear film break-up test and dry eye symptoms were assessed by the Ocular Surface Disease Index, both before surgery and 30 and 60 days after surgery. Results: In the preoperative analysis, 25.5% of the patients had dry eye according to the subjective criterion (Ocular Surface Disease Index ≥ 25%), while the proportion of patients with dry eye was 92.2% according to the objective criterion (tear film break-up test < 10 seconds). There was no correlation between tear film break-up test and Ocular Surface Disease Index (r = −0.14; p = 0.33). There was no reduction in dry eye symptoms (15.9 ± 17.6 versus 12.2 ± 13.2 versus 7.8 ± 11.5; p<0.001) nor in tear film break-up time (6.2 ± 2.2 versus 4.3 ± 2.0 versus 6.9 ± 2.0 seconds; p < 0.001) before, 30 and 60 days after surgery. Conclusion: Phacoemulsification triggers dry eye symptoms and changes Ocular Surface Disease Index and tear film break-up test values, with improvement over the postoperative days. Sixty days after surgery, the symptoms of dry eye assessed according to the Ocular Surface Disease Index improved. Regarding the tear film, evaluated by tear film break-up test, it was observed that there was a statistically significant worsening at 30 days, followed by an improvement in the postoperative period of 60 days. The results suggest that the clinical analysis of dry eye should be performed using different methods, preferably objective ones.

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BACKGROUND: The fluorescein clearance test (FCT) provides insight into the tear film dynamics. The purpose of this study was to describe an inexpensive and practical method for assessing FCT in dogs, using photography and software analysis, and to assess the retention time of 1 vs. 2 eye drops on the canine ocular surface. METHODS: (i) In vivo - Eight healthy German Shepherd dogs were recruited. Following topical anesthesia with 0.5% proxymetacaine, each eye sequentially received (1 week apart) either 1 drop (35 µL) or 2 drops (70 µL) of 0.5% fluorescein. A Schirmer strip was inserted in the ventral conjunctival fornix for 10 s at the following times: each 10 min for 100 min, 24 h, 48 h and 72 h. (ii) In vitro - Schirmer strips were placed for 10 s in contact with microplate wells containing 1 or 2 drops of 0.5% fluorescein. In both experiments, the fluorescein-impregnated Schirmer strips were immediately imaged, and the area and intensity of fluorescein uptake were analyzed with ImageJ software. For the in vitro experiment, images were evaluated by the same examiner (repeatability) or two examiners (reproducibility). RESULTS: Photography-based FCT was easy to perform and showed high repeatability and reproducibility (coefficients of variation ≤2.75%). In vivo, the area and intensity of fluorescein uptake on Schirmer strips were significantly greater at 30 min and 40 min post- fluorescein instillation in the 2 drops vs. 1 drop groups (p ≤ 0.044). Compared to baseline, the residual fluorescein uptake on Schirmer strips was < 5% at 60 min and 90 min in the 1 drop and 2 drops groups, respectively. CONCLUSIONS: Photography-based FCT is a practical and reliable diagnostic tool with various clinical and research applications in veterinary medicine. Instillation of two drops provided greater amount and longer retention on the anesthetized canine ocular surface than a single drop. Fluorescein clearance time of a single drop in dolichocephalic dogs is 60 min.

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BACKGROUND: Dacryocystorhinostomy (DCR) is the gold standard surgical treatment for nasolacrimal duct obstruction. External DCR is the traditional approach (EXT-DCR); however, the advent of minimally invasive surgeries and the development of optic fiber and laser technologies have made it possible to perform laser transcanalicular DCR (T-DCR), a minimally invasive procedure. This study measured the fluorescein transit time (FTT) after EXT-DCR or T-DCR to evaluate the lacrimal drainage and lacrimal pump function after these two types of DCR. SUBJECTS AND METHODS: A cross-sectional study of 50 patients who underwent EXT-DCR (EXT-DCR Group) or T-DCR (T-DCR Group), who were anatomically patent upon irrigation, with a minimum 6 months of follow up. The patients' FTT was measured; it was defined as the time from the instillation of the dye into conjunctival sac to its free flow from the rhinostomy site. This evaluation was performed through nasal endoscopy performed intranasally with a blue filter that enabled the faster detection of fluorescein from the ostium site. The mean FTTs of the two groups were compared using the two-sided Student's unpaired t-test. Other variables such as sex, age, previous lacrimal sac size, and the site and shape of the rhinostomy were evaluated to determine their possible relationships with FTT. RESULTS: The EXT-DCR group had 80% female patients at a mean age of 58 years. The T-DCR group had the same percentage of female patients (80%) and a mean age of 56 years. The mean FTT group was 47.48 sec in the EXT-DCR and 33.04 sec in the T-DCR group. Functional success was 88% in both groups. CONCLUSION: FTT in the DCR-T Group was significantly lower than in the EXT-DCR Group. No other variables exhibited a statistically significant correlation with FTT. Lacrimal drainage was found to be better after T-DCR than after EXT-DCR, results which show that this procedure could prevent lacrimal pump damage.

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Ghrelin is a stomach-derived peptide hormone that acts in the brain to regulate many important physiological functions. Ghrelin receptor, named the growth hormone secretagogue receptor (GHSR), is present in many brain areas with or without obvious direct access to ghrelin circulating in the bloodstream. Ghrelin is also present in the cerebrospinal fluid (CSF) but the brain targets of CSF ghrelin are unclear. Here, we studied which brain areas are accessible to ghrelin present in the CSF. For this purpose, we centrally injected mice with fluorescein-labeled ghrelin (F-ghrelin) peptide tracer and then systematically mapped the distribution of F-ghrelin signal through the brain. Our results indicated that centrally injected F-ghrelin labels neurons in most of the brain areas where GHSR is present. Also, we detected F-ghrelin uptake in the ependymal cells of both wild-type and GHSR-null mice. We conclude that CSF ghrelin is able to reach most of brain areas expressing GHSR. Also, we propose that the accessibility of CSF ghrelin to the brain parenchyma occurs through the ependymal cells in a GHSR-independent manner.

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BACKGROUND/AIMS: It is a challenge to adapt traditional in vitro diffusion experiments to ocular tissue. Thus, the aim of this work was to present experimental evidence on the integrity of the porcine cornea, barrier function and maintenance of electrical properties for 6 h of experiment when the tissue is mounted on an inexpensive and easy-to-use in vitro model for ocular iontophoresis. METHODS: A modified Franz diffusion cell containing two ports for the insertion of the electrodes and a receiving compartment that does not need gassing with carbogen was used in the studies. Corneal electron transmission microscopy images were obtained, and diffusion experiments with fluorescent markers were performed to examine the integrity of the barrier function. The preservation of the negatively charged corneal epithelium was verified by the determination of the electro-osmotic flow of a hydrophilic and non-ionized molecule. RESULTS: The diffusion cell was able to maintain the temperature, homogenization, porcine epithelial corneal structure integrity, barrier function and electrical characteristics throughout the 6 h of permeation experiment, without requiring CO(2) gassing when the receiving chamber was filled with 25 mM of HEPES buffer solution. CONCLUSION: The system described here is inexpensive, easy to handle and reliable as an in vitro model for iontophoretic ocular delivery studies.

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Schistosoma mansoni is responsible for lesions that can alter the hemodinamic of the portal venous circulation, lung arterial and venous sistemic systems. Therefore, hemodinamic changes in the ocular circulation of mansonic schistosomotic patients with portal hypertension and hepatofugal venous blood flow is also probable. The purpose of this study was to determine the fluorescein contrast arrival time at the retina of young patients with the hepatosplenic form of schistosomiasis, clinically and surgically treated. The control group included 36 non schistosomotic patients, mean age of 17.3 years, and the case group was represented by 25 schistosomotic patients, mean age of 18.2 years, who were cared for at The University Hospital (Federal University of Pernambuco, Brazil), from 1990 to 2001. They underwent digital angiofluoresceinography and were evaluated for the contrast arrival time at the early retinal venous phase of the exam. Both groups were ophthalmologically examined at the same hospital (Altino Ventura Foundation, Recife, Brazil), using the same technique. There was retardation of the retinal contrast arrival time equal or more than 70 sec in the eyes of three schistosomotic patients (12%) and in none of the control group, however, the mean contrast arrival time between the two groups were not statistically different. These findings lend support to the hypothesis that there could be a delay of the eye venous blood flow drainage.

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Angiotensin-(1-7) (Ang-(1-7)), a peptide constituent of the renin-angiotensin system, has been shown to act as a vasodilator mediator in pre-existing (skin) and newly formed vasculatures (14-day-old sponge implants). Blood flow was determined by the outflow rate of sodium fluorescein applied intradermally or intraimplant and the results were expressed in t(1/2) values (time taken for the fluorescence to reach 50% of the peak in the systemic circulation). We showed that the t(1/2) value was significantly lower (4.1+/-0.46) in the implants compared with the cutaneous vasculature (5.7+/-0.5). Ang-(1-7) 20 ng was able to decrease t(1/2) values in both vasculatures. The specific receptor antagonist, D-Ala7-Ang-(1-7) (A-779), prevented Ang-(1-7)-induced vasodilation and altered the basal vascular tone of the implants. The vasodilator effect was also abolished by nitric oxide (NO) synthase inhibitors in both vasculatures and by indomethacin in the implant. Selective AT(1) and AT(2) receptor antagonists did not alter the vasodilation induced by the peptide. These results establish the vasodilator effect of Ang-(1-7) in the cutaneous and implant vasculature and that the peptide is produced endogenously by the fibrovascular tissue, and suggest that this peptide contributes for the vasodilation found in newly formed vascular beds (wound healing, chronic inflammatory processes and tumors).

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Sponge-induced angiogenesis in mice and pharmacological reactivity of the neovasculature have been determined by a fluorimetric method. Pharmacokinetic studies following subcutaneous, intradermal, and intraimplant administration of sodium fluorescein resulted in a biphasic curve from which estimation of t1/2 for absorption and elimination of the dye were possible. Following topical injection of the dye at days 1, 4, 7, 10, and 14 postimplantation, measurement of fluorchrome generated emission in the systemic circulation reflected the development of blood flow in and around the implants and the interaction of the angiogenic site with the systemic circulation. The t1/2 values for the fluorescence peak in the bloodstream decreased steadily from an initial value of 6.41 +/- 0.28 min (avascular implant) to 2.78 +/- 0.23 min in fully vascularized implants (day 14). The reactivity of the neovasculature to ET-1 was dose-dependent and similar to the skin vasculature. By contrast, no reactivity to histamine was detected in the implant blood vessels, whereas it was present in the skin. These results show that the pharmacological response of the neovasculature differs from the response of mature blood vessels. The angiogenic stimulus (bFGF, 300 ng daily) decreased t1/2 for the fluorescence peak, whereas dexamethasone (1 mg/kg) increased it. Parallel histological studies corroborated the functional findings. These observations indicate the suitability of this assay to study angiogenesis, functional and pharmacological characterization of the neovasculature, and the interaction of the angiogenic site with the systemic circulation.

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