Positive corneoscleral rim culture in penetrating keratoplasty at the Porto Alegre Clinical Hospital

PURPOSE: To determine the incidence of positive corneoscleral rim cultures preserved in Optisol GS medium, to identify pathogens involved and possible recipient eye infection. METHODS: A hundred sixty-three corneoscleral rim cultures penetrating keratoplasties performed from January 2001 to January 2003 in the Hospital de Clínicas de Porto Alegre were reviewed. Enucleations and corneal storage were done as aseptic as possible and gentamicin 0.3% was instilled. Corneoscleral rim was divided into two segments, half was inoculated into Sabouraud broth and the other half into thioglycolate broth; inoculation into blood agar, chocolate agar and MacConkey agar was done later if necessary for pathogen identification. The receiver's eye data were reviewed. RESULTS: There were eleven positive cultures (6.7%) out of 163 evaluated corneoscleral rim cultures. Of these, four were Staphylococcus epidermidis, one was Staphylococcus aureus, one was Serratia sp., one was Pseudomonas aeruginosa and the other four were different subtypes of Candida (two Candida sp., one Candida albicans and one Candida parapapilosis). All pathogens were resistant to gentamicin. None of the eleven cases of positive corneoscleral rim cultures resulted in ocular infection at the receiver's eyes (six months follow-up). CONCLUSIONS: We found low rates of positive corneoscleral rim cultures after penetrating keratoplasty at the Porto Alegre Clinical Hospital. The most frequent involved pathogens were Staphylococcus sp and Candida sp. Although we did not identify any postoperative infection at the receiver's eyes, we recommend corneoscleral rim culture for guidance of postoperative infection, a rare but possible devastating ocular event.OBJETIVOS: Avaliar a incidência de positividade de culturas de halos doadores córneo-esclerais preservados em Optisol GS, identificar os patógenos envolvidos, a sensibilidade dos mesmos à gentamicina e a ocorrência de infecções em olhos receptores. MÉTODOS: Foram analisadas retrospectivamente 163 culturas de halos córneo-esclerais cujos botões corneanos foram utilizados em transplantes de córnea no Hospital de Clínicas de Porto Alegre entre janeiro de 2001 e janeiro de 2003. Os halos foram divididos em dois segmentos, metade inoculada em meio Sabouroud e a outra metade em tioglicolato, com posterior semeadura em ágar-sangue, ágar-chocoloate e meio de MacConkey, conforme necessidade para identificação dos patógenos. Os prontuários dos pacientes receptores foram revisados. RESULTADOS: Dos 163 halos analisados, 11 apresentaram culturas positivas, correspondendo a 6,7% do total. Destes, quatro foram por Staphylococcus epidermidis, um por Staphylococcus aureus, um por Serratia sp, um por Pseudomonas aeruginosa e os outros quatro por diferentes subtipos de Candida (dois por Candida sp, um por Candida albicans e um por Candida parapapilosis). No antibiograma, todas as bactérias apresentaram-se resistentes à gentamicina. Nenhum olho que recebeu córnea com cultura positiva apresentou infecção após a cirurgia. CONCLUSÕES: Baixos índices de positividade de cultura de halos utilizados em transplantes de córnea no Hospital de Clínicas de Porto Alegre foram encontrados. Os patógenos mais freqüentemente identificados não apresentam boa cobertura pelos antimicrobianos presentes nos meios de preservação. A cultura de halos corneanos é recomendada para auxílio no tratamento de possível infecção ocular pós-cirúrgica.Universidade Federal do Rio Grande do Sul Hospital de Clínicas de Porto AlegreUniversidade Federal de São Paulo (UNIFESP)Universidade de Passo FundoUNIFESPHospital de Clínicas de Porto AlegreUFRGS Faculdade de MedicinaUFRGS Hospital de Clínicas de Porto AlegreUFRGSUNIFESPSciEL

Comparison between conjunctival limbus and keratoconjunctival limbus autografts in the treatment of ocular chemical burns in rabbits

Purpose: To compare corneal recovery after ocular chemical burn in rabbit eyes treated with conjunctival limbus or keratoconjunctival limbus autografts. Methods: Thirty-five rabbits underwent a unilateral ocular chemical burn, including the cornea and the limbus, applying a NaOH 1 mol -1 solution. After 30 days, a conjunctival limbus autograft from the contralateral eye was performed in Group 2 (12 eyes); a keratoconjunctival limbus autograft from the contralateral eye was performed in Group 3 (11 eyes) and no surgeries were carried out in the control group (Group 1). Statistical analysis regarding induction and regression of corneal neovascularization, time for corneal re-epithelialization, rate of corneal transparency was performed. The corneal surface phenotype was also analyzed by monoclonal antibodies (AE-5). Results: After 90 days of follow-up, improvement of corneal transparency, decreased corneal neovascularization and corneal re-ephitelialization were significantly associated with limbal transplantation, carried out in Groups 2 and 3. The control group (Group 1) showed epithelial necrosis in all cases. Corneal surfaces of the operated eyes (Groups 2 and 3) showed a gradual decrease of goblet cells, a gradual increase of corneal epithelial cells, and postoperative stabilization after 30 days. Conclusions: Conjunctival limbus and keratoconjunctival limbus autografts produced the same clinical and epithelial phenotype results in an experimental model of chemical burns in rabbit eyes.Objetivo: Analisar e comparar a recuperação da córnea após queimadura química ocular, em olhos de coelhos tratados com transplante autólogo de limbo conjuntival e limbo córneo-conjuntival. Métodos: Um total de 35 coelhos foi submetido a uma queimadura química unilateral da córnea e limbo, com solução de hidróxido de sódio (NaOH) 1 mol -1. Após 30 dias da queimadura, foram constituídos 3 grupos. Os coelhos do Grupo 1(12) não foram operados e foram utilizados como controle. Os coelhos do Grupo 2 (12) foram submetidos a um transplante autólogo, utilizando limbo conjuntival do olho contralateral. Os coelhos do Grupo 3 (11) foram submetidos a um transplante autólogo, utilizando limbo córneo-conjuntival do olho contralateral. Foram estudados os seguintes itens: indução e regressão da neovascularização corneana, tempo de reepitelização corneana, alteração da transparência corneana e estudo do fenótipo corneano, empregando-se métodos de rotina hematoxilina-eosina (HE), método do ácido periódico - Schiff (PAS) e reação da peroxidase-antiperoxidase (PAP), utilizando anticorpos monoclonais. Resultados: Não houve diferenças estatisticamente significantes, nas variáveis estudadas, quando comparados os dois grupos operados. Houve diferenças estatisticamente significantes, em todas variáveis estudadas, quando comparados os grupos operados com o grupo controle. Notou-se diminuição gradativa do número de células caliciformes, reconhecidas pelo PAS e aumento gradativo do número de células epiteliais corneanas, reconhecidas pelo anticorpo monoclonal AE5, configurando-se, aos 90 dias de pós-operatório, um fenótipo predominantemente epitelial corneano na superfície corneana, independentemente da técnica cirúrgica utilizada. O grupo controle mostrou extensa necrose do epitélio corneano em todos os casos. Conclusões: Os transplantes autólogos de limbo conjuntival e de limbo córneo-conjuntival produziram os mesmos resultados clínicos e fenotípicos epiteliais em um modelo experimental de queimadura química em olhos de coelhos, configurando-se, aos 90 dias de pós-operatório, um fenótipo predominantemente epitelial corneano. O grupo controle mostrou defeitos epiteliais persistentes, aumento da neovascularização corneana, diminuição da transparência e fenótipo da superfície corneana tipicamente conjuntival.Universidade Federal do Rio Grande do Sul Faculdade de MedicinaMcGill University-Montreal Departamento de OftalmologiaUNIFESP-EPMUFRGS Faculdade de MedicinaUNIFESP, EPMSciEL

Corneal cross-linking in a child with osteogenesis imperfecta syndrome and keratoconus

Cross-linking (CXL) is a well-established procedure in children with keratoconus (KC), but cases of CXL and osteogenesis imperfecta (OI) have not been published in the literature, despite the association between physiopathology of these diseases. This is the first case, to the best of our knowledge, of a young girl with both OI and KC that underwent a CXL treatment. In this case, CXL was performed at 6-years-old prior to an expected progression, without complications and probably stopped further keratoconus progression

Ações de empresas brasileiras e suas ADRs: Uma nota sobre datas ex-dividend

Este trabalho analisou o comportamento das ações de empresas brasileiras e de suas ADRs listadas em bolsa, em períodos próximos ao 1° dia ex-dividend. Analisando os retornos, pode-se perceber que as ações locais tiveram um desempenho médio superior ao das ADRs nos dias anteriores à data do evento. Isto sugere que os investidores preferem comprar ações às ADRs em função da menor tributação dos dividendos no Brasil. Essa tendência se inverte na data do evento, quando as ADRs obtiveram um retorno superior ao das ações locais. A análise dos preços demonstrou que as ADRs são negociadas, em média, com um prêmio em relação as suas respectivas ações. Palavras-Chave: Dividendos, ADRs, Tributação, Arbitragem, Eficiência de Mercado, Formação de preços de ativos JEL: G12, G14, G35 This work analyses the performance of the Brazilian ADRs and their underlying stocks around the 1° ex-dividend day. The local stocks showed a better performance, on average, than the ADRs on the days preceding the event data. This fact suggests that investors prefer to buy local stocks on this period because they have to pay lower taxes in Brazil when they receive the dividend. This tendency is reverted on the 1° ex-dividend day, when the ADRs had a better performance than their underlying stocks. The analysis of the prices showed that the ADRs are negotiated with a premium on average. Key-words: Dividends, Taxes, ADRs, Market efficiency, Arbitrage, Stock pricesEste trabalho analisou o comportamento das ações de empresas brasileiras e de suas ADRs listadas em bolsa, em períodos próximos ao 1° dia ex-dividend. Analisando os retornos, pode-se perceber que as ações locais tiveram um desempenho médio superior ao das ADRs nos dias anteriores à data do evento. Isto sugere que os investidores preferem comprar ações às ADRs em função da menor tributação dos dividendos no Brasil. Essa tendência se inverte na data do evento, quando as ADRs obtiveram um retorno superior ao das ações locais. A análise dos preços demonstrou que as ADRs são negociadas, em média, com um prêmio em relação as suas respectivas ações. Palavras-Chave: Dividendos, ADRs, Tributação, Arbitragem, Eficiência de Mercado, Formação de preços de ativos JEL: G12, G14, G35 This work analyses the performance of the Brazilian ADRs and their underlying stocks around the 1° ex-dividend day. The local stocks showed a better performance, on average, than the ADRs on the days preceding the event data. This fact suggests that investors prefer to buy local stocks on this period because they have to pay lower taxes in Brazil when they receive the dividend. This tendency is reverted on the 1° ex-dividend day, when the ADRs had a better performance than their underlying stocks. The analysis of the prices showed that the ADRs are negotiated with a premium on average. Key-words: Dividends, Taxes, ADRs, Market efficiency, Arbitrage, Stock price

Sequential Intrastromal Corneal Ring Implantation and Cataract Surgery in a Severe Keratoconus Patient with Cataract

A 49-year-old man with an uncorrected visual acuity (UCVA) of 20 / 1000, a best spectacle-corrected visual acuity (BSCVA) of 20 / 400, keratometric readings of K1 = 59.88 × 82° / K2 = 45.88 × 172°, and an inferior steepening that was consistent with keratoconus in his left eye was treated with clear-cornea phacoemulsification and an intraocular lens (IOL) implantation after insertion of keraring intrastromal corneal ring segments for severe keratoconus and cataract. An asymmetrical pair of kerarings was implanted with the assistance of a femtosecond laser in September 2008; the one segment was 250 µm and the other was 150 µm and both were placed at 70°. Three months after the kerarings were implanted, clear-cornea phacoemulsification and IOL implantation were performed on the left eye. After surgery, both the UCVA and the BSCVA of the left eye improved by eight lines. Postoperative central keratometry showed a decrease of 7.35 diopters in the left eye. Both the postoperative refraction (-0.75 -0.75 × 60°) and the keratometric reading (K1 = 50.05 × 93° / K2 = 48.83 × 3°) remained stable one month following the procedures. Thus, the sequential order of intrastromal corneal rings implantation and cataract surgery can be considered as a treatment option in patients with severe keratoconus and cataract

Virulent T4 Acanthamoeba causing keratitis in a patient after swimming while wearing contact lenses in Southern Brazil

Several strains of free-living amoebae belonging to the genus Acanthamoeba can cause a painful sight-threatening disease of the cornea known as Acanthamoeba keratitis (AK). The numbers of AK cases keep rising worldwide mainly due to an increase in contact lens wearers and lack of hygiene in the maintenance of contact lenses and their cases. We report a case of AK in a healthy young woman admitted to the Hospital de Clinicas in Porto Alegre, southern Brazil. Corneal scrapings were examined for the presence of Acanthamoeba strains. The initial isolate was characterized by morphological and genotypic properties. The isolate belonged to group III according to Pussard and Pons’ cyst morphology. Analysis of its 18S rDNA sequence identified the isolate as genotype T4. The T4 genotype is the most commonly reported among keratitis isolates and the most common in environmental samples

Imidazolium ionic liquid as potential contact lens disinfectant inactivating cystic resistance forms from ACANTHAMOEBA keratitis

Keratitis caused by Acanthamoeba spp. is a rare disease, although increasingly common, especially among contact lens users. The occurrence and the devastating effect of this disease are associated with the lack of care in cleaning and disinfecting lenses and their storage cases, as well as ineffective drugs to mainly eliminate the parasite’s cysts. This work evaluated the amoebicidal activity of the imidazolium salt 1-hexadecyl-3-methylimidazolium chloride (C16MImCl) against cysts of two characterized isolates from Acanthamoeba keratitis cases (MZ404337 and MZ404332). The inactivation of 100% of the cysts was achieved at a concentration of 7.81 μg/mL for MZ404337 and of 1.95 μg/mL for MZ404332, both at 24 h and 48 h of exposure time. In contrast, a commercial formulation of chlorhexidine did not cause any reduction in the viability of the cysts. Related to the cytotoxicity to human HaCaT cells, C16MImCl is biocompatible at the concentration required to inactivate cysts. This shows that C16MImCl is a promising disinfectant for contact lenses and surfaces. KEY WORDS: 1-hexadecyl-3-methylimidazolium chloride; Acanthamoeba keratitis; cysts; chlorhexidine; cytotoxicity.Keratitis caused by Acanthamoeba spp. is a rare disease, although increasingly common, especially among contact lens users. The occurrence and the devastating effect of this disease are associated with the lack of care in cleaning and disinfecting lenses and their storage cases, as well as ineffective drugs to mainly eliminate the parasite’s cysts. This work evaluated the amoebicidal activity of the imidazolium salt 1-hexadecyl-3-methylimidazolium chloride (C16MImCl) against cysts of two characterized isolates from Acanthamoeba keratitis cases (MZ404337 and MZ404332). The inactivation of 100% of the cysts was achieved at a concentration of 7.81 μg/mL for MZ404337 and of 1.95 μg/mL for MZ404332, both at 24 h and 48 h of exposure time. In contrast, a commercial formulation of chlorhexidine did not cause any reduction in the viability of the cysts. Related to the cytotoxicity to human HaCaT cells, C16MImCl is biocompatible at the concentration required to inactivate cysts. This shows that C16MImCl is a promising disinfectant for contact lenses and surfaces. KEY WORDS: 1-hexadecyl-3-methylimidazolium chloride; Acanthamoeba keratitis; cysts; chlorhexidine; cytotoxicity