Navegando por Palavras-chave "Preservação de tecido"
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- ItemAcesso aberto (Open Access)Aplicação de modelos epidemiológicos para determinar fatores associados a qualidade de córneas em banco de olhos(Universidade Federal de São Paulo (UNIFESP), 2016-11-29) Aquino, Nathalia Mayumi Thomaz de [UNIFESP]; Hirai, Flavio Eduardo [UNIFESP]; http://lattes.cnpq.br/6575096591259140; http://lattes.cnpq.br/9462387847581411; Universidade Federal de São Paulo (UNIFESP)Objective: To develop a methodology using epidemiological models to identify factors related to transplanted cornea?s quality in Eye Banks. Methods: A case-control study was conducted to determine factors related to primary graft failure in the state of São Paulo between January 2010 and December 2013. Primary graft failure cases were defined as irreversible corneal edema in the immediately postoperative period, unresponsive to topical treatment. Controls were randomly selected from corneal transplants performed one week before or after the cases. Donors data were evaluated as cause of death, sex, age, endothelial cell count, time between death and enucleation, time to corneal preservation and preservation time before surgery. Statistical analysis between groups was performed and the odds ratio was calculated to determine factors related to primary failure. Results: Thirty-eight cases of primary graft failure were reported to the São Paulo State Transplant Center during the study period, leading to a selection of 152 controls. The cases had between 16 years to 79 years, averaging 46.1 years (SD = 16.5 years) and controls 4-79 years, mean 39.8 years (SD = 16.5 years) (p = 0.037). There were more men in both groups, 60.5% among cases and 66.4% among controls (p = 0.493). Time between death and enucleation was 4.6 hours for cases (sd = 3.7 hours) and 3.5 hours for controls (sd = 5.8horas), p = 0.255. Time between enucleation and tissue preservation was 5.7 hours (SD = 3.5 hours) for cases and 4.6 hours (SD = 5.1 hours) for controls, p 0.238. It was also verified that the time between the preservation and transplantation in cases averaged 9.5 days (SD = 2.7 days) and controls 7.9 days (SD = 2.8 days) (p = 0.001). In the multivariate analysis, each extra day of preservation increased the risk of primary failure by 23%. Regarding endothelial cell count, were verified 2518.3 cells / mm 2 (SD = 259.4 cells / mm2) in cases and 2627.0 cells / mm 2 (SD = 346.1 cells / mm2) in controls (p = 0.084). The main cause of death in both groups were cardiovascular disease (50.0% of cases and 49.3% among controls). Death from external causes were found in 18.4% of cases and 45.4% of controls. Other causes, such as cancer, accounted for 31.6% of deaths among cases and 5.3% among controls. The corneas of those who died from other causes than cardiovascular disease were 6.6 times more likely to develop primary graft failure after adjusting for other variables (odds ratio 6.6 (2.1 to 20.5)). Conclusion: The case-control study was useful to determine factors associated with primary graft failure and could be used as a tool for quality control in Eye Banks. In this study, primary graft failure was multifactorial and reflects directly the tissues quality and it?s processing. Factors such as gender, endothelial cell count, time between death and enucleation and time between enucleation and preservation were not associated with the morbidity. However, age, time between preservation and surgery and cause of death could influence the tissue?s quality, leading to higher rates of primary graft failure. Therefore, may be factors to be considered during the selection of corneas in Eye Banks.
- ItemAcesso aberto (Open Access)Avaliação da ceratoplastia lamelar manual com a utilização de tecido corneano liofilizado em ceratocone(Universidade Federal de São Paulo (UNIFESP), 2007) Farias, Roberta Jansen de Mello [UNIFESP]; Sousa, Luciene Barbosa de [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Objetivos: Desenvolver um método para liofilizar córneas e comparar o uso de córneas liofilizadas com córneas preservadas em optisol no transplante lamelar anterior. Métodos: As córneas liofilizadas foram avaliadas por microscopia de luz e eletrônica e comparadas com controles não liofilizados. Na segunda parte do estudo, realizou-se um ensaio clínico randomizado com 20 portadores de ceratocone e candidatos a transplante de córnea, onde 10 pacientes foram transplantados com córneas liofilizadas e outros 10 com córneas preservadas em Optisol GS® por até 13 dias. Os dados pré e pós- operatórios consistiram de: medidas de acuidade visual em tabela logmar, exames de topografia, orbscan, paquimetria e microscopia especular. Exames de microscopia confocal, biomicroscopia ultra-sônica, sensibilidade ao contraste e um questionário sobre qualidade de vida foram realizados no pós-operatório. Resultados: Liofilização de córneas com sacarose 2,3 molar por 40 minutos e sua reidratação com solução salina balanceada por 30 minutos foi considerado o melhor método para preservação de córneas a longo prazo para transplante lamelar anterior. O ensaio clínico não mostrou variação significante entre os grupos, exceto nos valores de acuidade visual sem correção que foram melhores no grupo liofilizado e nos valores de densidade de ceratócitos que foram maiores no grupo optisol. Conclusões: Liofilização é um método eficaz para a preservação de córneas para transplante lamelar anterior. Córneas liofilizadas e utilizadas para o transplante lamelar anterior apresentaram evolução clínica semelhante a das córneas preservadas em Optisol GS®.
- ItemAcesso aberto (Open Access)Comparação dos meios de preparação e preservação de membrana amniótica humana para uso no tratamento de doenças da superfície ocular(Universidade Federal de São Paulo (UNIFESP), 2015-12-31) Ferenczy, Peter Alexander Von Harbach [UNIFESP]; Sousa, Luciene Barbosa de [UNIFESP]; http://lattes.cnpq.br/2367491641205774; http://lattes.cnpq.br/4522482036126391; Universidade Federal de São Paulo (UNIFESP)Atualmente a membra amniótica (MA) tem obtido importância devido à comprovada capacidade de reduzir inflamação, auxiliar a cicatrização e epitelização, possuindo propriedades antimicrobianas e antivirais, além de baixa imunogenicidade. As indicações de seu uso na oftalmologia têm aumentado muito nas duas últimas décadas. Objetivo: descrever a estrutura básica e as propriedades biológicas da MA em relação aos componentes da sua matriz extracelular e fatores de crescimento, as consequências de diferentes técnicas empregadas na sua preservação e esterilização, métodos para remoção do epitélio e a comparação dos custos dos diferentes meios de conservação atualmente empregados. Desenho do estudo: revisão bibliográfica. Método: Pesquisa nas bases de dados Bireme, Pubmed, Cochrane, Scielo e Lilacs com as palavras-chave: membrana amniótica, transplante, reconstrução da córnea, doenças da conjuntiva. Resultados: A literatura é vasta na descrição dos efeitos de diversos agentes e técnicas na preparação da MA, dentre elas sua preservação, esterilização e desepitelização. A membrana desnuda tem sido a escolha para a reconstrução da superfície ocular, pois facilita a cicatrização. Em relação aos agentes conservantes, o glicerol é o meio mais utilizado mundialmente pelo baixo custo e facilidade de manuseio. Conclusão: a comparação das diversas técnicas nos guia na elaboração de protocolos de preparo da MA para uso oftalmológico. A membrana desnuda facilita a cicatrização em relação a com células epiteliais. O glicerol é o meio de conservação mais utilizado pelo baixo custo e facilidade de manuseio.
- ItemAcesso aberto (Open Access)Estudo morfológico do intestino delgado de ratos submetido à oxigenação hiperbárica hipotérmica(Universidade Federal de São Paulo (UNIFESP), 2007) Guimaraes, Fernando Augusto Garcia [UNIFESP]; Taha, Murched Omar [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Objetivo: Avaliar o grau de lesao do intestino delgado submetido a preservacao hipotermica e oxigenacao hiperbarica (OHB). Metodos: Foram utilizados 20 ratos Wistar machos, com peso medio de 264,33 g e idade de 3 meses. Apos irrigacao intraluminal e perfusao vascular, segmentos jejunais de 3cm de cada animal foram mantidos em Ringer lactato a temperatura entre 2 e 4°C (RLg) e distribuidos aleatoriamente em 4 grupos: Grupo Ia = acondicionamento em geladeira por 12 horas (n=10); Grupo Ib = aplicacao de OHB refrigerada por 12 horas (n=lO); Grupo lIa = acondicionamento em geladeira por 24 horas (n=lO); Grupo IIb = aplicacao de OHB refrigerada por 24 horas (n=lO). Avaliaram-se o grau de lesao da mucos a e a altura das vilosidades por H.E., bem como os indices de apoptose e de mitose pelo metodo de TUNEL e por expressao do PCNA, respectivamente. Resultados: Nos Grupos Ia e lIa, observaram-se maiores graus de lesao (Graus 6 e 7), com significante diminuicao da espessura da camada mucosa e aumento do indice de apoptose (p
- ItemAcesso aberto (Open Access)Falência primária pós-transplante de córnea em serviço universitário(Conselho Brasileiro de Oftalmologia, 2002-12-01) Hirai, Flávio Eduardo [UNIFESP]; Klatte, Stefan; Pacini, Keila Mattos [UNIFESP]; Sato, Elcio Hideo [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade de Hamburgo Faculdade de Medicina; Associação Panamericana de Banco de OlhosPurpose: To analyze the factors related to primary corneal graft failure after penetrating keratoplasty in the Corneal and External Diseases Section of the Federal University of São Paulo, Brazil. Methods: A retrospective study was performed using the charts of patients submitted to penetrating keratoplasty from July 1999 to March 2001. Cases of primary failure (group I) and patients submitted to the surgical procedure at the same period (group II) were selected and compared. Information collected from donors were age, cause of death, endothelial cell count, time between death and enucleation (T1), time between enucleation and preservation of the graft (T2) and time of tissue preservation until surgery (T3). Results: 164 patients were analyzed with 21 cases of primary failure (12.8%). The mean age of the donors of group I was 43.1 years (±22.0) and from group II was 47.9 years (±18.9). There was no statistical difference between the two groups considering the time intervals (T1, T2, T3). Causes of death included trauma, cancer and heart diseases. Conclusion: Differences in all analyzed factors were not significant between both groups. The difficulties in determining the causes of primary corneal graft failure suggests a multifactorial process involved in this problem. Well-trained Eye Bank staff and notifications about postoperative complications are important to decrease the primary failure incidence.
- ItemAcesso aberto (Open Access)Freeze-drying as an alternative method of human sclera preservation(Conselho Brasileiro de Oftalmologia, 2008-04-01) Frota, Ana Carolina de Arantes; Lima Filho, Acácio Alves de Souza [UNIFESP]; Dias, Ana Beatriz Toledo; Lourenço, Andréia Cristina dos Santos [UNIFESP]; Antecka, Emilia; Burnier Júnior, Miguel Noel Nascente [UNIFESP]; McGill University Department of Ophthalmology Henry C. Witelson Ocular Pathology Laboratory; Universidade Federal de São Paulo (UNIFESP)PURPOSE: To compare the effect of preserving sclera samples in either 95% ethanol or freeze-dried. METHODS: Ninety-six samples of human sclera were studied. Half of them were freeze-dried and half preserved in 95% ethanol. Preservation periods of 18, 45, 90 or 174 days were studied. Automated immunostaining was carried out in the Ventana BenchMarkR LT platform using collagen 1 and fibronectin antibodies. Histological staining was also performed with hematoxilin-eosin and Masson trichrome. Samples were classified according to the degree of collagen fiber parallelism (0-2), intensity of Masson staining (0-2), and the expression of both antibodies (0-3). Friedman and Wilcoxon tests were applied to compare preservation methods and p-values below 0.05 were considered to ensure statistical significance. RESULTS: Relevant results were found in three situations: (i) Friedman's test showed better collagen fiber integrity in the freeze-dried group rehydrated after 174-days as compared to the 90-day group; (ii) Wilcoxon's test showed better collagen fiber integrity in the freeze-dried group after 18 and 174 days as compared to the ethanol group; (iii) the freeze-dried group disclosed higher immunohistochemical expression for COL-1 antibody in the sclera samples rehydrated after 45, 90 and 174 days as compared to the ones rehydrated after 18 days. CONCLUSION: Histological and immunohistochemical analysis showed freeze-drying to be a superior method for sclera preservation as compared to 95% ethanol. This technique provides an easy method to manipulate tissue, with longer shelf life, and storage at room temperature.
- ItemAcesso aberto (Open Access)Membrana amniótica no tratamento dos afinamentos corneais e esclerais(Conselho Brasileiro de Oftalmologia, 2003-01-01) Fairbanks, Daniella [UNIFESP]; Vieira, Luiz Antônio [UNIFESP]; Santos, Walner Daros dos [UNIFESP]; Attie, Greicie Cristina Guerra [UNIFESP]; Gomes, José Álvaro Pereira [UNIFESP]; Freitas, Denise de [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Faculdade de Medicina do ABCPURPOSE: To evaluate the use of amniotic membrane (AM) as an adjunct to the treatment of corneal and scleral thinnings. METHODS: Amniotic membrane was obtained at the time of cesarean section and was preserved at -80ºC in glycerol and cornea culture media at a ratio of 1:1. Seven eyes from 7 patients were divided into Group 1: neurotrophic ulcers secondary to herpes simplex virus keratitis (2 cases), after corneal transplantation (1 case), and post palpebral radiation (1 case); and Group 2: scleral thinning after pterygium surgery with (2 cases) or without (1 case) beta-therapy. All cases underwent amniotic membrane transplantation to restore thickness and promote epithelialization. RESULTS: Mean follow-up time was 12 months (range, 11-15 months). One case of neurotrophic ulcer secondary to radiotherapy was unsuccessful. A successful outcome was observed in the other 6 cases. Regarding visual acuity, 1 case improved and the other 6 cases remained unchanged. The mean epithelialization time was 26.6 ± 5.8 days for group 1 and 10.6 ± 4.0 days for group 2. CONCLUSIONS: The use of amniotic membrane represents a useful alternative to ocular surface reconstruction in corneal and scleral thinning. More cases and a longer follow up are necessary to better evaluate this procedure.