The role of enzymes in the angiogenic activity of Hancornia speciosa latex

The Hancornia speciosa latex has shown angiogenic activity. Angiogenesis plays a major role in wound healing, and materials that stimulate this process could be used to develop drugs. This study aimed to explain the role of proteins in the H. speciosa serum fraction latex in angiogenesis. Hence, this material was treated with proteinase K and the proteins were inactivated. After protein inactivation, angiogenic activity was assessed with the chick chorioallantoic membrane assay. The result showed that the proteins in the serum fraction are responsible for angiogenic activity. Then, the total protein content in the serum fraction and its enzymatic activity were investigated. The low protein content observed in the H. speciosa serum fraction latex suggests that this biomaterial could be used to develop new drugs with a hypoallergenic response. Despite the low protein content, there was a significant enzymatic activity of at least three enzymes in the serum fraction latex: ß-1,3 glucanase, ß-glucosidase, and proteases. These enzymes seem to influence the healing process, assisting debridement, extracellular matrix remodeling, and collagen deposition, and decreasing the chances of contamination by microorganisms. In conclusion, the enzymes in the H. speciosa serum latex are associated with the angiogenic activity of this biomaterial and may be used to assist the wound healing process.

The use of Proteinase K to access genitalia morphology, vouchering and DNA extraction in minute wasps

ABSTRACT Genitalia are rich source of characters in insect taxonomy. Usually, they are examined after dissection and cleaning with potassium hydroxide (KOH), procedure that may damage both genital morphological structures and intracellular molecular contents. Enzymatic procedure with Proteinase K has been used to clean muscle off the genitalia while extract DNA, but its damage to the genital structures has not been evaluated. Herein, we qualitatively compare the use of KOH and Proteinase K to prepare genital structures in minute insects (Hymenoptera: Bethylidae). We show that Proteinase K is better to preserve the genital structure and provides quality DNA.

Evaluación de un método de extracción y purificación de DNA a partir de tejido muscular fijado en formaldehido de cadáveres no identificados / Evaluation of a method of extracting and purifying DNA from muscle tissue fixed in formaldehyde unidentified bodies / Avaliação de um método de extracção e purificação de ADN a partir de tecido muscular fixado em formaldeído corpos não identificados

La obtención de DNA humano en buena cantidad y alta pureza a partir de tejido muscular fijado en Formaldehido no tamponado es de suma importancia en la amplificación por la Reacción en Cadena de la Polimerasa (PCR) para su aplicación en estudios de identificación y filiación genética. En este estudio se evaluó la eficiencia del Kit QIAampR DNA FFPE TISSUE y una modificación del mismo basado en lavados con PBS y el tiempo de digestión con proteinasa K, frente a la cantidad y calidad de este ácido nucléico. Las diferencias fueron significativas entre los tiempos de acción con la proteinasa K (PK) en relación a la cantidad y en la pureza producto de los lavados del tejido muscular previa extracción. Estos resultados proporcionan una pauta para el diseño de experimentos de acuerdo con el efecto de la fijación, optimizando recursos humanos e insumos.

Obtaining human DNA in large quantity and high purity from muscle tissue fixed in formaldehyde unbuffered is of utmost importance in amplification by Chain Reaction (PCR) for application in identification studies and genetic affiliation. In this study, the efficiency of DNA FFPE TISSUE QIAampR Kit and a modification thereof based washes with PBS and the time of digestion with proteinase K, compared to the amount and quality of the nucleic acid were evaluated. Differences were significant between the exposure times with proteinase K (PK) in relation to the quantity and purity of the product prior washings muscle tissue extraction. These results provide a guideline for the design of experiments according to the effect of fixing, optimizing human resources and inputs.

A obtenção de DNA humano em grande quantidade e de alta pureza a partir de tecido muscular fixado em formol não tamponado é de extrema importância para a amplificação por Reacção em Cadeia (PCR), para sua aplicação em estudos de identificação e filiação genética. Neste estudo, a eficácia do kit QIAampR DNA FFPE TISSUE e uma modificação do processo por lavagens com PBS e o tempo de digestão com proteinase K, em comparação com a quantidade e a qualidade do ácido nucléico desta base. As diferenças foram significativas entre os tempos de exposição com proteinase K em relação à quantidade e pureza produto das lavagens do tecido muscular extraída previamente. Estes resultados fornecem uma diretriz para o desenho de experimentos de acordo com o efeito de fixação, otimizando recursos humanos e insumos.

Some physico-chemical parameters that influence proteinase K resistance and the infectivity of PrP Sc after high pressure treatment

Crude brain homogenates of terminally diseased hamsters infected with the 263 K strain of scrapie (PrP Sc) were heated and/or pressurized at 800 MPa at 60°C for different times (a few seconds or 5, 30, 120 min) in phosphate-buffered saline (PBS) of different pH and concentration. Prion proteins were analyzed on immunoblots for their proteinase K (PK) resistance, and in hamster bioassays for their infectivity. Samples pressurized under initially neutral conditions and containing native PrP Sc were negative on immunoblots after PK treatment, and a 6-7 log reduction of infectious units per gram was found when the samples were pressurized in PBS of pH 7.4 for 2 h. A pressure-induced change in the protein conformation of native PrP Sc may lead to less PK resistant and less infectious prions. However, opposite results were obtained after pressurizing native infectious prions at slightly acidic pH and in PBS of higher concentration. In this case an extensive fraction of native PrP Sc remained PK resistant after pressure treatment, indicating a protective effect possibly due to induced aggregation of prion proteins in such buffers.

Técnicas de purificación y ruptura de quistes de Giardia spp / Purification and breaking techniques of cysts of Giardia spp

El objetivo de este trabajo fue optimizar y evaluar las técnicas de purificación, aislamiento y ruptura de quistes de Giardia spp a partir de heces formoladas para la obtención de ADN. La materia fecal filtrada fue sometida a 3 técnicas de purificación, utilizando soluciones de formol-éter, sacarosa y formol-éter más sacarosa. La solución de sacarosa permitió aislar los quistes con menos detritos. Los quistes purificados fueron tratados con 3 técnicas para la ruptura de los mismos: shock osmótico y calor, degradación química y shock térmico, acción enzimática y efecto mecánico. Solamente con la técnica de shock térmico, acción enzimática y efecto mecánico se observaron bandas fluorescentes en geles de agarosa. Los resultados de este trabajo permiten contar con una metodología de rutina, simple, que podría ser usada en los pasos previos a la técnica de PCR para la genotipificación de este parásito.

The purpose of this study was to optimize and evaluate the purification techniques, isolation and breaking of cysts of Giardia spp from fecal samples to isolate DNA. Filtrated fecal samples were tested in 3 purification techniques: Telleman solution, sucrose and Telleman plus sucrose. The sucrose solution let us to isolate the cysts with less detritus. The cleaned cysts were splited in 3 techniques to test the breaking: osmotic shock and heat, chemistry degradation and thermic shock, enzymatic action and mechanic effect. Only the last method was successful and showed bands in agarose gel. The result of this study shows a routine and common method which could be used in the previous steps to the PCR technique for the genotypification of these parasites.

Comparison of four extraction methods to detect hepatitis A virus RNA in serum and stool samples

The efficiency of extraction methods for hepatitis A virus (HAV) RNA in clinical samples is of great importance for molecular diagnosis, especially in regions endemic for HAV, such as Brazil. We compared the efficiency of four different extraction techniques in serum and stool samples for the detection of hepatitis A virus by reverse transcription PCR (RT-PCR). We used PCR to analyse serum and stool samples of 12 patients who were referred to the Brazilian Reference Center for Viral Hepatitis (BRCVH) in Rio de Janeiro. The methods tested were Proteinase K, Silica, TRIzol and Guanidine isothiocyanate. Proteinase K extraction was the best method for serum samples; it detected the HAV-RNA in 11 of the 12 samples. The guanidine isothiocyanate method was the most effective for stool samples, detecting HAV-RNAs in 9 of the samples. The TRIzol« method worked best with serum samples, and the silica method was unsatisfactory with both serum and stool samples. The RNA extraction method affected the outcome. The use of appropriate RNA extraction methods is a critical step for successful and valid PCR studies on clinical samples. We recommend that RNA extraction techniques be carefully selected for their efficiency with each type of specimen

Purificación parcial y empleo de fracciones glicosídicas de Trypanosoma cruzi en el diagnóstico de la enfermedad de Chagas / Partial purification and use of Trypanosoma cruzi glycosidic fractions for Chagas disease diagnosis

En el diagnóstico serológico de la enfermedad de Chagas se emplean fracciones proteicas y glicoproteicas de Trypanosoma cruzi, las cuales se degradan por la acción de proteasas endógenas del parásito, esto amerita el uso de inhibidores para su conservación encareciendo el costo del antígeno. La posibilidad de utilizar fracciones glicosídicas del parásito, resistentes a la acción de proteasas resolvería el problema, permitiendo obtener antígenos estables, de alta sensibilidad y a bajo costo. Esta alternativa se ve reforzada por la existencia en sueros de pacientes chagásicos de anticuerpos anti-galactosil dirigidas contra fracciones oligosacáridas de T. cruzi. El objetivo de este trabajo fue obtener fracciones glicosídicas de T. cruzi y evaluar su utilidad en el diagnóstico serológico de la enfermedad de Chagas. Se emplearon masas de parásitos de los cuatro estadios de T. cruzi, a partir de las cuales se obtuvieron proteínas y glicoproteínas totales, así como fracciones glicosídicas, éstas últimas mediante proteólisis exhaustiva con Proteinasa K. Se analizaron las fracciones proteicas, glicoproteicas y glicosídicas mediante SDS-PAGE y tinción específica para proteínas (Coomassie/Plata), así como para glico-proteínas y fracciones glicosídicas (APABGP). Se determinó la naturaleza antigénica de las diferentes fracciones mediante Western Blot y luminografía, utilizando suero control hiperinmune anti-epimastigota y "pool" de sueros chagásicos humanos. Finalmente se estudió, mediante ELISA, la capacidad discriminativa de las fracciones glicosídicas de los diferentes estadios para sueros de pacientes chagásicos y no chagásicos y la sensibilidad de las fracciones respecto al suero control. Se evidencia que: a) existen polipéptidos, glicopéptidos y fracciones glicosídicas comunes y específicos de estadio; b) los epimastigotas y metacíclicos son más ricos en glicoproteínas antigénicas respecto a los tripomastigotas y amastigotas; c) existe una relación entre el patrón de fracciones glicosídicas y el tipo de hospedador; d) las fracciones glicosídicas sirven como antígenos para discriminar mediante ELISA pacientes chagásicos y no chagásicos, pero muestran títulos menores que los antígenos proteicos y glicoproteicos totales. Se concluye que es posible desarrollar un kit diagnóstico para...

A comparison of three DNA extractive procedures with Leptospira for polymerase chain reaction analysis

Three DNA extraction methods were evaluated in this study: proteinase K followed by phenol-chloroform; a plant proteinase (E6870) followed by phenol-chloroform; and boiling of leptospires in 0.1 mM Tris, pH 7.0 for 10 min at 100°C, with no phenol treatment. Every strain treated with proteinase K or E6870 afforded positive polymerase chain reaction (PCR) reaction. On the other hand, from five strains extracted by the boiling method, three did not feature the 849 bp band characteristic in Leptospira. We also evaluated by RAPD-PCR, DNAs from serovars isolated with proteinase K and proteinase 6870 with primers B11/B12. Each of the DNA samples provided PCR profiles in agreement with previous data. Moreover, the results with E6870 showed less background non-specific amplification, suggesting that removal of nucleases was more efficient with E6870. The limit for detection by PCR using Lep13/Lep14 was determined to be 10(2) leptospira, using the silver stain procedure.

Use of a cysteine proteinase from Carica candamarcensis as a protective agent during DNA extraction

We describe the use of a plant cysteine proteinase isolated from latex of Carica candamarcensis as a protective agent during isolation of bacterial DNA following growth in culture of these cells. Between 100 to 720 units of proteinase (1 µg = 6 units) afforded good DNA protection when incubated with various kinds of microorganisms. Agarose gel electrophoresis showed that the resulting DNA was similar in size to DNA preparations obtained by treatment with proteinase K. The viability of the resulting material was checked by PCR amplification using species-specific primers. After standing at room temperature (25oC) for 35 days, the enzyme lost 10 percent of its initial activity. The enzyme stability and good yield of DNA suggest the use of this proteinase as an alternative to proteinase K

Detection of mycoplasmas in urethral swabs from HIV-1 infected patients and control individuals using culture techniques and polymerase chain reaction

O objetivo do presente estudo foi determinar a prevalência de determinadas espécies de micoplasmas, tais como, Mycoplasma hominis, Ureaplasma urealyticum e Mycoplasma penetrans, em swabs uretrais de pacientes infectados com HIV-1 comparando com um grupo controle. Micoplasmas foram detectados por técnicas padräo de cultivo e pela reacäo de polimerase em cadeia para a qual foram utilizados "primers" genericos obtidos da regiäo conservada 16sRNA e "primers" nos dois metodos foi comparavel. Contudo, o PCR mostrou ser mais sensivel nas condicöes empregadas enquanto que o cultivo permitiu a quantificacäo dos isolados. Os resultados demonstraram näo haver diferenças significantes (p<0,05) nas taxas de positividade entre os metodos empregados para a detecçäo dos micoplasmas