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1.
Braz. j. microbiol ; 49(3): 656-661, July-Sept. 2018. tab, graf
Article in English | LILACS | ID: biblio-951809

ABSTRACT

Abstract Hamelia patens, is a plant traditionally used to treat a variety of conditions among the Huastec people of Mexico. The objective of this study is to characterize the phenolic content and critically examine the antimicrobial activity of leaf extracts H. patens, obtained by maceration, Soxhlet and percolation, using ethanol as 70% solvent. Phenolic compounds are characterized by liquid chromatography, coupled to a High Resolution Mass Spectrometry, and the antimicrobial activity was studied from the inhibitory effect of each extract for Escherichia coli, Staphylococcus aureus, Salmonella typhi and S. paratyphi, and by the Minimum Bactericidal Concentration, the percentage of activity and the Index of Bacterial Susceptibility of each extract. The phenolic compound identified in different concentrations in the three extracts was epicatechin. The extracts obtained by the three methods had antimicrobial activity, however, there was no significant difference (p < 0.05) between the Minimum Bactericidal Concentration of the extracts obtained by maceration, percolation and Soxhlet. The results of this study contribute to the body of knowledge on the use of extracts in controlling microorganisms with natural antimicrobials.


Subject(s)
Phenols/isolation & purification , Phenols/pharmacokinetics , Plant Extracts/isolation & purification , Plant Extracts/pharmacokinetics , Hamelia/chemistry , Chemical Fractionation/methods , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/pharmacology , Phenols/chemistry , Staphylococcus aureus/drug effects , Plant Extracts/chemistry , Microbial Sensitivity Tests , Escherichia coli/drug effects , Mexico , Anti-Bacterial Agents/chemistry
2.
An. acad. bras. ciênc ; 90(1): 461-470, Mar. 2018. tab, graf
Article in English | LILACS | ID: biblio-886908

ABSTRACT

ABSTRACT The aim of this study was to optimize the dextranase production by fungus Pochonia chlamydosporia (VC4) and evaluate its activity in dextran reduction in sugarcane juice. The effects, over the P. chlamydosporia dextranase production, of different components from the culture medium were analyzed by Plackett-Burman design and central composite design. The response surface was utilized to determine the levels that, among the variables that influence dextranase production, provide higher production of these enzymes. The enzymatic effect on the removal of dextran present in sugarcane juice was also evaluated. It was observed that only NaNO3 and pH showed significant effect (p<0.05) over dextranase production and was determined that the levels which provided higher enzyme production were, respectively, 5 g/L and 5.5. The dextranases produced by fungus P. chlamydosporia reduced by 75% the dextran content of the sugarcane juice once treated for 12 hours, when compared to the control treatment.


Subject(s)
Models, Statistical , Saccharum/metabolism , Dextranase/biosynthesis , Hypocreales/enzymology , Temperature , Dextrans/metabolism , Culture Media/metabolism , Electrophoresis, Polyacrylamide Gel , Enzyme Activation , Fruit and Vegetable Juices/analysis , Chemical Fractionation/methods , Hydrogen-Ion Concentration , Nitrates
3.
Article in English | LILACS | ID: biblio-894172

ABSTRACT

Sperm contains a wealth of cell surface receptors and ion channels that are required for most of its basic functions such as motility and acrosome reaction. Conversely, animal venoms are enriched in bioactive compounds that primarily target those ion channels and cell surface receptors. We hypothesized, therefore, that animal venoms should be rich enough in sperm-modulating compounds for a drug discovery program. Our objective was to demonstrate this fact by using a sperm-based phenotypic screening to identify positive modulators from the venom of Walterinnesia aegyptia. Methods Herein, as proof of concept that venoms contain interesting compounds for sperm physiology, we fractionated Walterinnesia aegyptia snake venom by RP-HPLC and screened for bioactive fractions capable of accelerating mouse sperm motility (primary screening). Next, we purified each compound from the positive fraction by cation exchange and identified the bioactive peptide by secondary screening. The peptide sequence was established by Edman sequencing of the reduced/alkylated compound combined to LC-ESI-QTOF MS/MS analyses of reduced/alkylated fragment peptides following trypsin or V8 protease digestion. Results Using this two-step purification protocol combined to cell phenotypic screening, we identified a new toxin of 7329.38 Da (actiflagelin) that activates sperm motility in vitro from OF1 male mice. Actiflagelin is 63 amino acids in length and contains five disulfide bridges along the proposed pattern of disulfide connectivity C1-C5, C2-C3, C4- C6, C7-C8 and C9-C10. Modeling of its structure suggests that it belongs to the family of three finger toxins with a noticeable homology with bucandin, a peptide from Bungarus candidus venom. Conclusions This report demonstrates the feasibility of identifying profertility compounds that may be of therapeutic potential for infertility cases where motility is an issue.(AU)


Subject(s)
Animals , Male , Rats , Sperm Motility , Spermatozoa/chemistry , Elapid Venoms/isolation & purification , Elapid Venoms/therapeutic use , Phospholipases A2 , Acetylcholinesterase , Tandem Mass Spectrometry/methods , Chemical Fractionation/methods , Mice
4.
Acta toxicol. argent ; 25(1): 1-11, mayo 2017. ilus, tab
Article in Spanish | LILACS | ID: biblio-886578

ABSTRACT

Los contaminantes del aire han sido y siguen siendo, los principales factores que contribuyen a las enfermedades crónicas como el asma y enfermedades cardiovasculares. La contaminación del aire por material particulado (PM) es un problema mundial y en los últimos años, el PM se ha convertido en un tema importante de investigación ya que tiene un impacto negativo significativo en la salud humana; el PM es generado por las actividades industriales y tubos de escape de vehículos de motor. Sin embargo, diversos componentes nocivos del PM, como los hidrocarburos aromáticos policiclicos (HAP) en general, son sos­pechosos de ser carcinogénicos. Este trabajo tiene como objetivo identificar los HAP presentes en el PM2.5 del aire de Cúcuta, extraídos por primera vez, mediante el sistema diclorometano-etanol-tolueno e investigar la importancia del fraccionamiento de la materia organica del PM2.5 para detectar los HAP presentes en las fracciones del PM2.5. La identificación de los HAP considerados como contaminantes prioritarios y reconocidos por su afectación a la salud de la población se realizó, mediante cromatografía de gases con detector FID. Los efectos genotoxicos de la materia orgánica del PM2.5 extraída con una mezcla de DCM-etanol-tolueno fueron evaluados mediante el ensayo Cometa.


Air pollutants have been and still are the main factors that contribute to chronic diseases such as asthma and cardio­vascular disease. Air pollution by particulate matter (PM) is a global problem and in recent years, the PM has become an important research topic since it has a significant negative impact on human health; the PM is generated by industrial activities and exhaust pipes of motor vehicles. However, various harmful components of PM such as polycyclic aromatic hydrocarbons (PAHs) in gen­eral, are suspected of being carcinogenic. This work aims to identify the PAHs present in the PM 2.5 air Cúcuta, first extracted by the dichloromethane-ethanol-toluene system and investigate the importance of organic matter fractionation of PM 2.5 to detect PAHs present in the fractions of PM 2.5. The identification of PAHs considered as priority pollutants and recognized for their effects on health of the population was performed by gas chromatography with FID detector. The genotoxic effects of PM2.5 organic mat­ter, extracted with a mixture of DCM-ethanol-toluene, was evaluated by the Comet assay.


Subject(s)
Humans , Carcinogens, Environmental , Genotoxicity , Polycyclic Aromatic Hydrocarbons/toxicity , Chemical Fractionation/methods , Colombia , Comet Assay/methods , Environmental Pollution
5.
Arch. latinoam. nutr ; 65(2): 119-127, June 2015. ilus, tab
Article in English | LILACS | ID: lil-752722

ABSTRACT

The objective of this work was investigate the synergistic, additive and antagonistic effects of fruit mixtures on total antioxidant capacities and bioactive compounds in tropical fruit juices, and optimize its formulation by the response surface methodology based on the responses: total polyphenols (TP), total antioxidant capacity (TAC), ascorbic acid content and sensorial acceptance. Camu-camu, acerola and acai were the major factors that influenced the antioxidant potential of the juice; and the yellow mombin showed a positive effect on the acceptance of the tropical juice. It was observed an antagonistic effect between acerola and camu-camu for the TAC response. The optimum formulation obtained was 20% acerola, 10% camu-camu, 10% yellow mombin, 10% cashew apple and 10% acai, which was responsible for a response of 155.46 mg.100 g-1 of ascorbic acid, 103.01 mg of GAE.100 g-1 of TP, 10.27 μM Trolox g-1 of TAC and approximately 6.1 of acceptance.


El objetivo de este trabajo fue investigar los efectos sinérgicos, aditivos y antagónicos de mezclas de diferentes frutas tropicales en la capacidad antioxidante total (TAC) y compuestos bioactivos presentes en los jugos mixtos, y optimizar su formulación por la metodología de superficie de respuesta basado en las evaluaciones de: polifenoles totales (TP), capacidad antioxidante total (TAC), contenido de ácido ascórbico y la aceptación sensorial. Camu-camu, acerola y acai fueron las frutas que más influyeron en el potencial antioxidante del jugo mixto; y el jobo mostró un efecto positivo en la aceptación del jugo mixto tropical. Se observó un efecto antagónico entre acerola y camu-camu para la TAC. La formulación óptima obtenida contenía 20% acerola, 10% de camu-camu, 10% el jobo, 10% de manzana de marañón y 10% de acai, la cual ha proporcionado contenidos medio de 155,46 mg.100 g-1 de ácido ascórbico, 103,01 mg de GAE.100 g-1 de TP, 10,27 mM Trolox g-1 de TAC y aproximadamente 6.1 de aceptación sensorial.


Subject(s)
Humans , Fruit and Vegetable Juices/analysis , Anacardiaceae/chemistry , Anacardium/chemistry , Ananas/chemistry , Antioxidants/analysis , Ascorbic Acid/analysis , Chemical Fractionation/methods , Drug Interactions , Euterpe/chemistry , Mangifera/chemistry , Polyphenols/analysis , Research Design , Taste
6.
Indian J Exp Biol ; 2015 Feb; 53(2): 98-103
Article in English | IMSEAR | ID: sea-158385

ABSTRACT

Anticancer potential of Moringa oleifera L. extracts have been well established. However, there are no reports on the isolated molecules/fractions from these extracts which are responsible for the anticancer/cytotoxic activity. Thus, in the present study, we explored the same. The n-hexane, chloroform, ethyl acetate, methanol extracts of the M. oleifera leaves and 15 fractions (F1 to F15) of ethyl acetate extract were evaluated for their in vitro and in vivo anticancer activity using Hep-2 cell lines and Dalton’s lymphoma ascites model in mice, respectively. Among the tested samples, the F1 fraction showed potential cytotoxic effect in Hep-2 cell lines with a CTC50 value of 12.5 ± 0.5 µg/ml. In vivo studies with the doses 5 and 10 mg/kg, p.o. demonstrated significant reduction in body weight and increased the mean survival time compared to the control group. These results were also comparable to the standard, 5-Fluorouracil, treated animals. We have also successfully isolated and characterized the anticancer fraction, F1 from the leaves of M. oleifera L.


Subject(s)
Acetates/chemistry , Animals , Antineoplastic Agents/isolation & purification , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Cell Survival/drug effects , Chlorocebus aethiops , Chemical Fractionation/methods , Chloroform/chemistry , Female , Hep G2 Cells , Hexanes/chemistry , Humans , Inhibitory Concentration 50 , Methanol/chemistry , Moringa oleifera/chemistry , Neoplasms, Experimental/drug therapy , Neoplasms, Experimental/pathology , Plant Extracts/isolation & purification , Plant Extracts/pharmacology , Survival Analysis , Time Factors , Vero Cells
7.
Arch. latinoam. nutr ; 63(2): 180-187, June 2013. tab
Article in English | LILACS | ID: lil-740239

ABSTRACT

The present study investigated six varieties of locally grown wheat (Lasani, Sehar, Miraj-08, Chakwal-50, Faisalabad-08 and Inqlab) procured from Punjab Seed Corporation, Lahore, Pakistan for their proximate contents. On the basis of protein content and ready availability, Faisalabad-08 (FD-08) was selected to be used for the assessment of comparative efficiency of various methods used for gluten extraction. Three methods, mechanical, chemical and microbiological were used for the extraction of gluten from FD-08. Each method was carried out under ambient conditions using a drying temperature of 55°C. Mechanical method utilized four different processes viz:- dough process, dough batter process, batter process and ethanol washing process using standard 150 mesh. The starch thus obtained was analyzed for its proximate contents. Dough batter process proved to be the most efficient mechanical method and was further investigated using 200 and 300 mesh. Gluten content was determined using sandwich ω-gliadin enzyme-linked immunosorbent assay (ELISA).The results of dough batter process using 200 mesh indicated a starch product with gluten content of 678 ppm. Chemical method indicated high gluten content of more than 5000 ppm and the microbiological method reduced the gluten content from 2500 ppm to 398 ppm. From the results it was observed that no gluten extraction method is viable to produce starch which can fulfill the criteria of a gluten free product (20ppm).


El presente roduc seis variedades de trigo cultivado localmente (Lasani, Sehar, Miraj-08, Chakwal-50, Faisalabad-08 e Inqlab) obtenidos por sus contenidos proximales en Punjab Seed Corporation, Lahore, Pakistán. Sobre la base del contenido de roduct y su fácil disponibilidad, Faisalabad-08 (Fd-08) fue seleccionado para ser utilizado para la evaluación de la eficacia comparadativa de los diferentes métodos utilizados para la extracción de gluten. Tres métodos fueron utilizados para la extracción de gluten; mecánico, químico y microbiológico realizados en condiciones ambientales utilizando una roduct e de secado de 55°C. El método mecánico roduct cuatro procesos diferentes, a saber: proceso de masa, proceso de rebozado de masa, proceso de pasta y proceso de lavado en etanol empleando malla estándar de 150 mesh. El almidón obtenido se analizó por sus contenidos proximales. El contenido de gluten se roduct usando roduct ω-gliadina, ensayo de inmunoabsorción ligado a enzimas (ELISA). El proceso de rebozado de masa fue el método roduct más eficiente y se investigó adicionalmente usando malla 200 y 300 mesh. El proceso de rebozado de masa usando malla 200 generó un almidón con contenido de gluten de 678 ppm. El método químico produjo un contenido de gluten de más de 5.000 ppm, y el método microbiológico redujo el contenido de gluten de 2500 ppm a 398 ppm. A partir de estos resultados se roduct que ningún de estos métodos de extracción de gluten fue es viable para roduct almidón que pueda cumplir los criterios de un roduct libre de gluten (20 ppm).


Subject(s)
Glutens/isolation & purification , Triticum/chemistry , Chemical Fractionation/methods , Food Analysis/methods , Food Handling/methods
8.
Journal of Veterinary Science ; : 107-114, 2013.
Article in English | WPRIM | ID: wpr-169638

ABSTRACT

Despite the development of new technologies, new challenges still remain for large scale proteomic profiling when dealing with complex biological mixtures. Fractionation prior to liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis is usually the preferred method to reduce the complexity of any biological sample. In this study, a gel LC-MS/MS approach was used to explore the stage specific proteome of Cryptosporidium (C.) parvum. To accomplish this, the sporozoite protein of C. parvum was first fractionated using SDS-PAGE with subsequent LC-MS/MS analysis. A total of 135 protein hits were recorded from 20 gel slices (from same gel lane), with many hits occurring in more than one band. Excluding all non-Cryptosporidium entries and proteins with multiple hits, 33 separate C. parvum entries were identified during the study. The overall goal of this study was to reduce sample complexity by protein fractionation and increase the possibility of detecting proteins present in lower abundance in a complex protein mixture.


Subject(s)
Chemical Fractionation/methods , Chromatography, Liquid/methods , Cryptosporidium parvum/chemistry , Electrophoresis, Polyacrylamide Gel/methods , Gene Expression Profiling/methods , Proteome/analysis , Proteomics/methods , Protozoan Proteins/analysis , Sporozoites/chemistry , Tandem Mass Spectrometry/methods
9.
Indian J Biochem Biophys ; 2012 Apr; 49(2): 109-114
Article in English | IMSEAR | ID: sea-140226

ABSTRACT

Invertase was purified from rose (Fructus cynosbati) hips by ammonium sulfate fractionation and hydroxyapatite column chromatography. The enzyme was obtained with a yield of 4.25% and about 10.48-fold purification and had a specific activity of 8.59 U/mg protein. The molecular mass of invertase was estimated to be 66.51 kDa by PAGE and 34 kDa by SDS-PAGE, indicating that the native enzyme was a homodimer. The enzyme was a glycoprotein and contained 5.86% carbohydrate. The Km for sucrose was 14.55 mM and the optimum pH and temperature of the enzyme were 4.5 and 40°C, respectively. Sucrose was the most preferred substrate of the enzyme. The enzyme also hydrolyzed D(+) raffinose, D(+) trehalose and inulin (activity 39.88, 8.12 and 4.94%, respectively of that of sucrose), while D(+) lactose, cellobiose and D(+) maltose showed no effect on the enzyme. The substrate specificity was consistent with that for a β-fructofuranoside, which is the most popular type in the higher plants. The enzyme was completely inhibited by HgCl2, MnCl2, MnSO4, FeCl3, Pb(NO3)2, ammonium heptamolybdate, iodoacetamide and pyridoxine hydrochloride. It was also inhibited by Ba(NO3)2 (86.32%), NH4Cl (84.91%), MgCl2 (74.45%), urea (71.63%), I2 (69.64%), LiCl (64.99%), BaCl2 (50.30%), Mg(NO3)2 (49.90%), CrCl3 (31.90%) and CuSO4 (21.45%) and but was activated by Tris (73.99%) and methionine (12.47%).


Subject(s)
Carbohydrate Metabolism , Chemical Fractionation/methods , Enzyme Activation/drug effects , Enzyme Inhibitors/pharmacology , Fruit/enzymology , Hydrogen-Ion Concentration , Molecular Weight , Rosa/enzymology , Substrate Specificity , Temperature , beta-Fructofuranosidase/antagonists & inhibitors , beta-Fructofuranosidase/chemistry , beta-Fructofuranosidase/isolation & purification , beta-Fructofuranosidase/metabolism
10.
Bol. latinoam. Caribe plantas med. aromát ; 9(6): 495-500, nov. 2010. tab
Article in English | LILACS | ID: lil-644990

ABSTRACT

Natural essential oils are used extensively in fragrances, flavorants, and in the food and pharmaceutical industries. During hydrodistillation, a part of the essential oil becomes dissolved in the condensate and lost as this water is discarded. In this study, carvone and limonene content recovered from hydrodistillation waste water of caraway fruit were quantified using two methods for recovering dissolved aromatic molecules from condensate water: extraction through distillation and extraction by means of a solvent. This allows for the conservation of useful molecules which are typically discarded with the waste water produced during the distillation process. The objective of this study was to quantify the carvone and limonene content recoverable from waste water derived from the distillation of caraway essential oil. The well-known Clevenger method and a simpler, more practical technique employing cyclohexane as a solvent were employed to determine the recoverable content of aromatic molecules from the hydrosol. The chemical compositions of the respective recovered extracts were compared with those of the primary oils to analyze the efficacy of these methods. Recovered extract accounted for 10 to 40 percent of the total oil yield. The limonene and carvone molecules recovered using these methods were quantified through gas chromatography in order to characterize the composition of the secondary extract produced.


Los aceites esenciales naturales se utilizan ampliamente en las fragancias, saborizantes, y en la industria alimentaria y farmacéutica. Durante la hidrodestilación, una parte del aceite esencial se disuelve en el condensado y se pierde como agua de descarga. En este estudio, el contenido de carvona y limoneno recuperados del agua de desecho de la hidrodestilación de la fruta de alcaravea se cuantificaron utilizando dos métodos para recuperar las moléculas aromáticas disueltas en el agua condensada: extracción a través de la destilación y la extracción con un disolvente. Esto permite la conservación de las moléculas útiles que normalmente son desechadas con las aguas residuales producidas durante el proceso de destilación. El objetivo de este estudio fue cuantificar el contenido de carvona y limoneno recuperable de las aguas residuales procedente de la destilación del aceite esencial de alcaravea. El conocido método de Clevenger y una técnica sencilla y práctica que emplea ciclohexano como disolvente fueron utilizadas para determinar el contenido de moléculas aromáticas contenidas en el hidrosol. La composición química de los extractos recuperados fue comparada con los aceites primarios para analizar la eficacia de estos métodos. El extracto recuperado representa del 10 al 40 por ciento del contenido total de aceite esencial. Las moléculas de limoneno y carvona recuperadas mediante estos métodos se cuantificaron mediante cromatografía de gases con el fin de caracterizar la composición del extracto secundario.


Subject(s)
Oils, Volatile/isolation & purification , Oils, Volatile/chemistry , Carum , Cyclohexanes/analysis , Chemical Fractionation/methods , Monoterpenes/analysis , Chromatography, Gas , Distillation , Terpenes/analysis
11.
Acta toxicol. argent ; 18(1): 10-20, June 2010. ilus, tab
Article in Spanish | LILACS | ID: lil-661947

ABSTRACT

Las mordeduras producidas por serpientes venenosas son un serio problema médico en varias regiones del mundo y sobre las cuales los sistemas de salud actúan en diferentes grados en lo referente a tratamiento y prevención. Sin embargo, el tratamiento de las mordeduras de serpientes venenosas en animales domésticos puede resultar difícil por diversos motivos, siendo uno de estos la baja oferta o ausencia de antivenenos para uso veterinario. Las presiones comerciales en la industria farmacéutica han llevado a una reducción en la producción de antivenenos en varias partes del mundo, su disponibilidad es, a veces, bastante limitada y en algunos casos, son imposibles de conseguir. En este trabajo, inmunizamos caballos con veneno de serpientes Sudamericanas para obtener el plasma hiperinmune que fue procesado para obtener IgG entera o fragmentos F(ab´)2 usando dos métodos convencionales (fraccionamiento por ácido caprílico o doble precipitación salina y digestión con pepsina). Los antivenenos así obtenidos fueron probados en sus características bioquímicas e inmunoquímicas, así como en su potencia neutralizante. El SDS-PAGE de los antivenenos mostró bandas en el orden de los 150 y 100 kDa en los antivenenos conteniendo IgG entera o fragmentos F(ab´)2, respectivamente. La presencia de albúmina o contaminantes de alto o bajo peso molecular no fue detectada en ninguna de las preparaciones. No se observaron diferencias importantes en la potencia neutralizante de los antivenenos, aunque el costo de producción fue mucho más bajo en la obtención de IgG completa. A partir de esto, se sugiere que los bajos costos de producción en la obtención de antivenenos de IgG entera para uso veterinario, hacen a esta tecnología adecuada y rentable cuando la producción de F(ab´)2 no es posible.


Bites by venomous snakes are a serious medical problem in several regions of the world, on which the different health systems act with different modalities. Nevertheless, the treatment of venomous snakebites in domestic animals can turn difficult due several problems among which, the conspicuous, is the low availability or lack of antivenoms for veterinary use. As commercial pressures on the pharmaceutical industry have led to a reduction in the production of antivenins in several parts of the world, their availability is sometimes rather limited and sometimes these products are impossible to obtain. In this work, we immunized horses with venom of South American vipers to obtain hyperimmune plasma. The plasma was processed to separate whole IgG of F(ab´)2 fragments using two conventional methods (caprylic acid fractionation or double saline precipitation and pepsin digestion). The obtained antivenins were tested for their biochemical and immunochemical characteristics and neutralizing potency. The SDS-PAGE of the antivenins showed, in the processed antivenin, bands in the order of 150 and 100 kDa in the whole IgG or F(ab´)2 fragments, respectively. The presence of albumin or contaminants of high or low molecular weight was not detected in any of the preparations. No important differences were observed in the neutralizing potency of the antivenins, although production cost was very low with the method used to obtain pure IgG. The low production cost makes the production of antivenins for veterinary use profitable when the production of F(ab´)2 fragments is not possible.


Subject(s)
Animals , Antivenins/therapeutic use , Immunoglobulin Fab Fragments/pharmacology , Snake Bites , Snake Venoms , Caprylates , Chemical Fractionation/methods , Horses
13.
Rev. bras. cancerol ; 50(3): 239-249, jul.-set. 2004. ilus, graf
Article in Portuguese | LILACS | ID: lil-468357

ABSTRACT

A radioterapia é uma opção terapêutica padrão para o tratamento radical do câncer de próstata localizado. Umamelhora nos índices terapêuticos, através da elevação da dose total do tratamento pelas irradiações, tem sidoexaustivamente pesquisada nos últimos anos, com o auxílio de modernos e mais precisos sistemas de planejamentoe de tratamento. Recentemente, um interesse renovado sobre o uso do hipofracionamento para o tratamento docâncer de próstata pela radioterapia está sendo observado. Tal mudança de estratégia está relacionada ao novoconceito radiobiológico de que os tumores prostáticos possuem um índice α/β muito mais baixo do que previamenteestimado. O hipofracionamento, portanto, parece ser uma opção terapêutica interessante para este tumor, tendoem vista a possibilidade de melhora do índice terapêutico com uma alteração na dose diária de radioterapia. Estetrabalho avalia criticamente o valor do hipofracionamento nos tumores prostáticos malignos.


Subject(s)
Humans , Male , Middle Aged , Chemical Fractionation/methods , Prostatic Neoplasms , Radiotherapy
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