RESUMO
In the present study, a sequential staining process of polyphenoloxidase and phenoloxidase enzymes was designed by the zymography technique. As a first step, electrophoresis was carried out under native conditions, and later, first staining was carried out with a revealing solution of 3-methyl-2-benzothiazoline hydrazone (MBTH)-3-dimethylamino benzoic acid (DMAB) that allowed the visualization of polyphenoloxidase enzymes, and later and using the same gel, we proceeded to the differential staining of phenoloxidase, adding a solution of H2O2. The technique was standardized using commercial enzymes of laccase (T. versicolor) and horseradish. The technique was used to identify polyphenoloxidases (laccases) and phenoloxidases (lignin peroxidase) of crude extracts obtained from the growth of the basidiomycete Lentinus strigosus on Pinus radiata. The technique showed great sensitivity to detect the different enzymatic activities (1.56 Activity Unit/mL minimum) in the same gel without interference between the enzymes and the solutions used. On the other hand, the efficiency of the technique was compared with the substrates that are commonly used for the detection of this type of activities such as 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) and guaiacol, observing greater sensitivity and minimal interference, so that the present method will allow in the same gel, and visualize polyphenoloxidase and phenoloxidase activities simultaneously facilitating expression studies.
RESUMO
In the present work, a strain of the basidiomycete fungus Trametes polyzona was used to decolorize the Amaranth dye. The decolorization was carried out in an Airlift reactor with three flow regimes: 1, 2, and 3 vvm. The results showed that the decolorization was a function of the flow regime. The decolorization times for the regimes of 1, 2, and 3 vvm were 30, 25, and 19 days, respectively. The COD (Chemical Oxygen Demand) decreased from 1600 to 72 mg COD/L. The enzymatic activity kinetics of laccase (Lcc), lignin peroxidase (LiP), and manganese peroxidase (MnP) were determined. In all the treatments, the enzyme LiP was expressed during the first 6 days, at which point 80% decolorization was observed, whereas Lcc and MnP enzymes were produced from day 6 until the end of the decolorization process. The effluent generated showed no inhibitory effects on the growth of the algae Nannochloropsis salina. T. polyzona showed great versatility in the decolorization of synthetic effluents containing the Amaranth dye, and the fungus was able to use this dye as its only carbon source starting at the beginning of the process. LiP was the enzyme that contributed the most to the decolorization process, and on average, 95% decreases in color and the COD were observed.
RESUMO
El Retinoblastoma es la neoplasia ocular más frecuente en pediatría. La Terapia radiante externa fue hasta hace una década el tratamiento conservador de elección. Luego se incluyó la quimio reducción; en un intento de evitar la radioterapia externa y sus complicaciones. En este estudio retrospectivo evaluamos los resultados del tratamiento conservador con terapia radiante externa o con quimio reducción en el servicio de oftalmología del Hospital Nacional de Pediatría Juan P. Garrahan, desde 1987 a 2009. De un total de 571 pacientes con diagnóstico de Retinoblastoma, 341 fueron unilaterales y 217 bilaterales. De estos últimos se analizaron 166 pacientes cuya edad media al diagnostico fue de 12 meses. Se trataron 332 ojos de 166 pacientes con Retinoblastoma bilateral, 157 ojos (47,3%) recibieron quimioreducción como tratamiento inicial, 115 ojos (34,6%) fueron enucleados al inicio, 45 ojos (13,6%) recibieron radioterapia externa como único tratamiento y 15 ojos (4,5%) recibieron tratamiento local solo (laser o crioterapia) como primera elección. Se analizaron los datos con el programa estadístico STATA 12.0 stataCorp Texas.USA. La agudeza visual final fue superior a 20/70 en el 51,5% de los pacientes e inferior en el 48,5%. Se encontró una relación significativa (p=0,005) entre el estadio al diagnóstico y la agudeza visual final; los pacientes con discapacidad visual se presentaron con estadios avanzados. Se evaluaron todas las orbitas enucleadas (157); de ellas el 74,5% recibieron radioterapia externa antes o después de la enucleación. El 24,8% de las orbitas irradiadas presentaron deformidad de la cavidad, con mala adaptación de prótesis y retracción orbitaria, el 70,1% presentaron cambios que permitían una adaptación de prótesis aceptable con alguna limitación de movilidad y solo 6 orbitas (5,12%) presentaban una muy buena cavidad para adaptación cosmética. Cuarenta de 157 orbitas enucleadas no recibieron radioterapia en ningún momento (25,5%), el 92,5% de ellas presentaron buena adaptación y solo el 7,5% tuvieron problemas de adaptación debido a complicaciones postoperatorias. El diagnóstico precoz, el tratamiento oportuno, y el uso de quimio reducción como terapia inicial en Retinoblastoma intraocular, permiten aumentar la tasa de preservación del globo ocular y reducen o eliminan la necesidad de recibir Terapia radiante externa, evitando sus secuelas (AU)
Retinoblastoma is the most common ocular neoplasia in childhood. External beam radiation therapy was the conservative treatment of choice until a decade ago. Subsequently, chemoreduction was added trying to avoid external beam radiation therapy and its complications. In this retrospective study we assess the results of conservative therapy with external beam radiation therapy or with chemoreduction at the Department of Ophthalmology at the Pediatric Hospital Juan P. Garrahan between 1987 and 2009. Of a total of 571 patients with a diagnosis of retinoblastoma, 341 had unilateral and 217 bilateral retinoblastoma. Of the latter patients, 166 patients were analyzed with a mean age at diagnosis of 12 months. Overall, 332 eyes of 166 patients with bilateral retinoblastoma were treated; at initial treatment 157 eyes (47.3%) underwent chemoreduction, 115 eyes (34.6%) were enucleated, 45 eyes (13.6%) underwent external beam radiation therapy as the only treatment, and 15 eyes (4.5%) only received local treatment (laser or cryotherapy) as a first choice. Data were analyzed using STATA 12.0 stataCorp Texas.USA. Final visual acuity was more than 20/70 in 51.5% and less in 48.5% of the patients. A significant relationship (p=0.005) between stage at diagnosis and final visual acuity was found; patients with visual impairment presented with advanced stages. All enucleated orbits were assessed (157); 74.5% underwent external beam therapy before or after enucleation. Of all irradiated orbits, 24.8% presented with cavity deformity, poor prosthesis fit, or contraction of the socket. Of all patients, 70.1% presented with changes that allowed acceptable fitting of the prosthesis with slight movement limitation and only 6 orbits (5.12%) had a good cavity for cosmetic appearance. Forty of 157 enucleated orbits did not receive radiation therapy at any moment (25.5%); 92.5% of them had a good fitting and in only 7.5% fitting problems due to postoperative complications were found. Early diagnosis, adequate treatment, and use of chemoreduction as initial therapy of intraocular retinoblastoma allow for an increased rate of preservation of the eye and reduce or eliminate the need for external beam therapy and its sequelae (AU)
