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Preparação, estabilidade e conservaçao do fator tecidual ativador de plasminogênio (rt-PA) para uso oftalmológico

Preparação, estabilidade e conservaçao do fator tecidual ativador de plasminogênio (rt-PA) para uso oftalmológico

Autores:

Juliana M. Ferraz Sallum,
Isabel Batista,
Acácio Alves Souza Lima Filho,
Michel Eid Farah,
Rubens Belfort Jr.

ARTIGO ORIGINAL

Arquivos Brasileiros de Oftalmologia

versão impressa ISSN 0004-2749versão On-line ISSN 1678-2925

Arq. Bras. Oftalmol. vol.60 no.1 São Paulo fev. 1997

http://dx.doi.org/10.5935/0004-2749.19970104

SUMMARY

Introduction:

The tissue plasminogen activator (t-PA), a fibrinolitic system component, activates the plasminogen into plasmin, which degrades the fibrin net. The recombinant tissue plasminogen activator has been used in ophthalmology to control the post-operative fibrin formation complications. The comercial t-PA available has a higher dose than necessary in ophthalmology. If it can be shared in doses the coasts will reduced.

Purpose:

To check if the comercial rt-PA, for cardiologic use, can be, diluted and used in ophthalmology, and if the activity remains after storage, and eventualy determine the best storage and utilization methods.

Material and methods:

The rt-PA initial lytic activity was studied on fibrin net substract, and residual activity after long term storage at -20ºC and -70ºC. The material sterility was tested in culture plates.

Results:

The rt-PA activity after 6 months storage at -70ºC was 40,7% of non storage rt-PA activity, and at -20ºC it was 34,9%. Samples kept at -20ºC for 6 months and then left at roam temperature 24 hours before testing, showed an activity of 27,9%. No contamination was found in any sample.

Conclusion:

The best way tested of storage rt-PA is at -70ºC. And in arder to keep the total potential activity, it should be used immediately after defrost.

Key works: Tissue plasminogen activator; fibrinolysis; fibrin; inflamation

REFERÊNCIAS

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