RESUMEN
OBJECTIVE: This case-control study aimed to evaluate the effects of conventional radiotherapy (RT) on the prevalence and populations of oral microorganisms in head and neck cancer patients who did not receive adequate preventive dental care. It was hypothesized that side effects of radiotherapy could be associated with radiation dose, microbiological aspects, and socioeconomic conditions of the patients. DESIGN: Twenty-eight dentate patients with head and neck cancer submitted to RT were included in the study. Radiation dose received varied from 4320 to 7020 cGy. Patients with the same demographic and health conditions, but no history of cancer or antineoplastic treatment were used as controls. Clinical examinations were carried out before RT, 15-22â¯days after starting RT, immediately after and 6 months after RT. Supra and subgingival biofilms were collected and cultivated onto selective and non-selective media. Isolates were identified by biochemical and physiological characteristics. Stimulated and unstimulated salivary flow rate and saliva buffer capacity were also determined. RESULTS: Mucositis, dermatitis, xerostomia, dysgeusia, dysphagia and candidiasis were common after starting RT and during the treatment period. Xerostomia was followed by a decrease in salivary pH and buffer capacity, which showed association with the increase of cariogenic cocci and yeast populations, which were also associated with deterioration of hygiene. Candida and family Enterobacteriaceae showed increased prevalence with RT, and were associated with the occurrence of mucositis and xerostomia. CONCLUSIONS: Modifications in oral biofilms of irradiated patients showed association with xerostomia and hygiene conditions, which reinforces the necessity of improving patient compliance to oral health care programs.
Asunto(s)
Encía/microbiología , Neoplasias de Cabeza y Cuello/complicaciones , Neoplasias de Cabeza y Cuello/microbiología , Microbiota/efectos de la radiación , Radioterapia/efectos adversos , Adolescente , Adulto , Anciano , Bacterias/clasificación , Bacterias/aislamiento & purificación , Bacterias/efectos de la radiación , Biopelículas/efectos de la radiación , Brasil , Candida/aislamiento & purificación , Candida/efectos de la radiación , Candidiasis/etiología , Estudios de Casos y Controles , Trastornos de Deglución/etiología , Dermatitis/etiología , Relación Dosis-Respuesta en la Radiación , Disgeusia/etiología , Enterobacteriaceae/aislamiento & purificación , Enterobacteriaceae/efectos de la radiación , Femenino , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Concentración de Iones de Hidrógeno , Masculino , Persona de Mediana Edad , Mucositis/etiología , Higiene Bucal , Saliva/química , Uso de Tabaco/efectos adversos , Xerostomía/etiología , Adulto JovenRESUMEN
PURPOSE: To investigate the effects of amifostine on bacterial translocation and overgrowth in colonic flora after acute radiation enteritis in a rat model. METHODS: Thirty-two female Wistar albino rats were divided into four groups: Group-1 (n=8): only normal saline was administered intraperitoneally. Group-2 (n=8): first serum saline was administered intraperitoneally and 30 minutes later 20 Gy radiation was applied to abdominopelvic region. Group-3 (n=8): only amifostine 200 ml/kg was administered intraperitoneally and radiation was not applied. Group-4 (n=8): first amifostine 200 ml/kg was administered intraperitoneally and 30 minutes later 20 Gy radiation was applied to abdominopelvic region. On the 5th day after radiation, samples of mesenteric lymph tissues and cecal contents were taken by laparotomy for microbiological culture. RESULTS: Intraperitoneal amifostine administration significantly decreased the bacterial overgrowth related to radiation in colon but did not significantly decrease the bacterial translocation. CONCLUSION: Although not providing a full protection on the damaged mucosal barrier, amifostine significantly decreased the bacterial overgrowth in the cecal content after high dose radiation. There is a need to find out appropriate amifostine dose under different radiation applications avoiding bacterial translocation in gastrointestinal system.
Asunto(s)
Amifostina/farmacología , Traslocación Bacteriana/efectos de los fármacos , Enteritis/inducido químicamente , Enterobacteriaceae/efectos de la radiación , Traumatismos Experimentales por Radiación/microbiología , Protectores contra Radiación/farmacología , Animales , Ciego/microbiología , Ciego/efectos de la radiación , Enteritis/microbiología , Enteritis/prevención & control , Enterobacteriaceae/fisiología , Femenino , Linfa/microbiología , Dosis de Radiación , Traumatismos Experimentales por Radiación/prevención & control , Ratas WistarRESUMEN
ABSTRACT PURPOSE: To investigate the effects of amifostine on bacterial translocation and overgrowth in colonic flora after acute radiation enteritis in a rat model. METHODS: Thirty-two female Wistar albino rats were divided into four groups: Group-1 (n=8): only normal saline was administered intraperitoneally. Group-2 (n=8): first serum saline was administered intraperitoneally and 30 minutes later 20 Gy radiation was applied to abdominopelvic region. Group-3 (n=8): only amifostine 200 ml/kg was administered intraperitoneally and radiation was not applied. Group-4 (n=8): first amifostine 200 ml/kg was administered intraperitoneally and 30 minutes later 20 Gy radiation was applied to abdominopelvic region. On the 5th day after radiation, samples of mesenteric lymph tissues and cecal contents were taken by laparotomy for microbiological culture. RESULTS: Intraperitoneal amifostine administration significantly decreased the bacterial overgrowth related to radiation in colon but did not significantly decrease the bacterial translocation. CONCLUSİON: Although not providing a full protection on the damaged mucosal barrier, amifostine significantly decreased the bacterial overgrowth in the cecal content after high dose radiation. There is a need to find out appropriate amifostine dose under different radiation applications avoiding bacterial translocation in gastrointestinal system.
Asunto(s)
Animales , Femenino , Traumatismos Experimentales por Radiación/microbiología , Protectores contra Radiación/farmacología , Amifostina/farmacología , Traslocación Bacteriana/efectos de los fármacos , Enteritis/inducido químicamente , Enterobacteriaceae/efectos de la radiación , Dosis de Radiación , Traumatismos Experimentales por Radiación/prevención & control , Ciego/efectos de la radiación , Ciego/microbiología , Ratas Wistar , Enteritis/microbiología , Enteritis/prevención & control , Enterobacteriaceae/fisiología , Linfa/microbiologíaRESUMEN
OBJECTIVE: Solar disinfection of water has been shown to be an effective treatment method in the developing world, but not specifically in a wilderness or survival setting. The current study sought to evaluate the technique using materials typically available in a wilderness or backcountry environment. METHODS: Untreated surface water from a stream in rural Costa Rica was disinfected using the solar disinfection (SODIS) method, using both standard containers as well as containers and materials more readily available to a wilderness traveler. RESULTS: Posttreatment samples using polyethylene terephthalate (PET) bottles, as well as Nalgene and Platypus water containers, showed similarly decreased levels of Escherichia coli and total coliforms. CONCLUSIONS: The SODIS technique may be applicable in the wilderness setting using tools commonly available in the backcountry. In this limited trial, specific types of containers common in wilderness settings demonstrated similar performance to the standard containers. With further study, solar disinfection in appropriate conditions may be included as a viable treatment option for wilderness water disinfection.
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Países en Desarrollo , Desinfección/métodos , Enterobacteriaceae/efectos de la radiación , Luz Solar , Purificación del Agua/métodos , Vida Silvestre , Costa Rica , Desinfección/instrumentación , Escherichia coli/efectos de la radiación , Proyectos Piloto , Plásticos/análisis , Tereftalatos Polietilenos/análisis , Ríos/microbiología , Microbiología del Agua/normas , Purificación del Agua/instrumentaciónRESUMEN
This study aimed at evaluating the bacteriological effects of the treatment of sheep meat contaminated with total coliforms, coliforms at 45 °C and Salmonella spp. by using irradiation at doses of 3 kGy and 5 kGy. Thirty sheep meat samples were collected from animals located in Rio de Janeiro State, Brazil, and then grouped in three lots including 10 samples: non-irradiated (control); irradiated with 3 kGy; and irradiated with 5 kGy. Exposure to gamma radiation in a 137Cs source-driven irradiating facility was perfomed at the Nuclear Defense Section of the Brazilian Army Technological Center (CTEx) in Rio de Janeiro. The samples were kept under freezing temperature (-18 °C) until the analyses, which occurred in two and four months after irradiation. The results were interpreted by comparison with the standards of the current legislation and demonstrated that non-irradiated samples were outside the parameters established by law for all groups of bacteria studied. Gamma irradiation was effective in inactivating those microorganisms at both doses tested and the optimal dose was achieved at 3 kGy. The results have shown not only the need for sanitary conditions improvements in slaughter and processing of sheep meat but also the irradiation effectiveness to eliminate coliform bacteria and Salmonella spp.
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Animales , Desinfección/métodos , Enterobacteriaceae/aislamiento & purificación , Enterobacteriaceae/efectos de la radiación , Rayos gamma , Carne/microbiología , Salmonella/aislamiento & purificación , Salmonella/efectos de la radiación , Brasil , Microbiología de Alimentos/métodos , Ovinos , TemperaturaRESUMEN
This study aimed at evaluating the bacteriological effects of the treatment of sheep meat contaminated with total coliforms, coliforms at 45 °C and Salmonella spp. by using irradiation at doses of 3 kGy and 5 kGy. Thirty sheep meat samples were collected from animals located in Rio de Janeiro State, Brazil, and then grouped in three lots including 10 samples: non-irradiated (control); irradiated with 3 kGy; and irradiated with 5 kGy. Exposure to gamma radiation in a (137)Cs source-driven irradiating facility was performed at the Nuclear Defense Section of the Brazilian Army Technological Center (CTEx) in Rio de Janeiro. The samples were kept under freezing temperature (-18 °C) until the analyses, which occurred in two and four months after irradiation. The results were interpreted by comparison with the standards of the current legislation and demonstrated that non-irradiated samples were outside the parameters established by law for all groups of bacteria studied. Gamma irradiation was effective in inactivating those microorganisms at both doses tested and the optimal dose was achieved at 3 kGy. The results have shown not only the need for sanitary conditions improvements in slaughter and processing of sheep meat but also the irradiation effectiveness to eliminate coliform bacteria and Salmonella spp.
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Desinfección/métodos , Enterobacteriaceae/aislamiento & purificación , Enterobacteriaceae/efectos de la radiación , Rayos gamma , Carne/microbiología , Salmonella/aislamiento & purificación , Salmonella/efectos de la radiación , Animales , Brasil , Microbiología de Alimentos/métodos , Ovinos , TemperaturaRESUMEN
The purpose of this research was to determine the feasibility of a UV photoreactor for the disinfection of effluent from a polishing pond following a UASB reactor treating domestic wastewater. For this, a 20 mm diameter photoreactor (20.7 litre volume) equipped with four 30 W submerged low-pressure mercury arc lamps was used. Three tests with contact times and doses ranging from 45 to 90 s and from 16.9 to 31.3 mW s cm(-2) were carried out. Inactivation of total coliforms and Escherichia coli varied from 2.6 to 3.4 log-units, even with the presence of suspended solids in the range of 87 to 102 mg L(-1). These results have shown that UV radiation disinfection of pond effluents can be a feasible alternative in areas with land restriction.
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Desinfección/métodos , Enterobacteriaceae/efectos de la radiación , Rayos Ultravioleta , Eliminación de Residuos Líquidos/métodos , Contaminantes del Agua/efectos de la radiación , Reactores Biológicos , Recuento de Colonia Microbiana , Enterobacteriaceae/aislamiento & purificación , Escherichia coli/aislamiento & purificación , Escherichia coli/efectos de la radiación , Tamaño de la Partícula , Contaminantes del Agua/aislamiento & purificaciónRESUMEN
The aim of this study was to evaluate the effects of the photosensitizers Rose Bengal and erythrosin combined with a light-emitting diode (LED) on Enterobacteriaceae. Twelve Enterobacteriaceae strains isolated from the oral cavities of patients undergoing prolonged antibiotic therapy, including three Escherichia coli, three Enterobacter cloacae, three Klebsiella oxytoca and three Klebsiella pneumoniae, were studied. An Enterobacteriaceae suspension (10(6) cells/ml) was prepared from each clinical strain isolated from the human oral cavity and subjected to the following treatments: LED and Rose Bengal, LED and erythrosin, LED and physiological solution, and physiological solution only as control. A blue LED unit (460 nm), and Rose Bengal and erythrosin at a concentration of 50 micromol/l were used. After incubation at 37 degrees C for 48 h, the number of colony-forming units (CFU) was calculated and subjected to analysis of variance (ANOVA). The Enterobacterial strains were sensitive to photodynamic therapy with Rose Bengal. There was a reduction of approximately 7.14 log10 for Enterobacter cloacae, 7.73 log10 for Escherichia coli, 6.76 log10 for Klebsiella pneumoniae and 7.21 log10 for Klebsiella oxytoca. However, photodynamic therapy using erythrosin did not reduce the numbers of CFUs per milliliter compared to the control group. The use of the LED alone had no toxic effect on the strain tested. The Enterobacteriaceae strains studied were sensitive to photodynamic therapy with Rose Bengal.
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Enterobacteriaceae/efectos de los fármacos , Eritrosina/farmacología , Colorantes Fluorescentes/farmacología , Fotoquimioterapia , Fármacos Fotosensibilizantes/farmacología , Rosa Bengala/farmacología , Enterobacter cloacae/efectos de los fármacos , Enterobacter cloacae/efectos de la radiación , Enterobacteriaceae/efectos de la radiación , Escherichia coli/efectos de los fármacos , Escherichia coli/efectos de la radiación , Humanos , Klebsiella oxytoca/efectos de los fármacos , Klebsiella oxytoca/efectos de la radiación , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/efectos de la radiaciónRESUMEN
Water supply for human consumption requires certain quality that reduces health risks to consumers. In this sense, the process of disinfection plays an important role in the elimination of pathogenic microorganisms. Even though chlorination is the most applied process based on its effectiveness and cost, its application is being questioned considering the formation of disinfection by-products (DBPs). Therefore, alternative disinfectants are being evaluated and some treatment processes have been proposed to remove DBPs precursors (organic matter. This paper reports the results of disinfection of a non conventional source of water (aquifer recharged unintentionally with raw wastewater) with peracetic acid (PAA) and ultraviolet radiation (UV) as well as nanofiltration (NF) followed by chlorination to produce safe drinking water. The results showed that a dose of 2 mg/L PAA was needed to eliminate total and faecal coliforms. For UV light, a dose of 12.40 mWs/cm2 reduced total and faecal coliforms below the detection limit. On the other hand, chlorine demand of water before NF was 1.1-1.3 mg/L with a trihalomethane formation potential (THMFP) of 118.62 microg/L, in contrast with chlorination after NF where the demand was 0.5 mg/L and THMFP of 17.64 microg/L. The recommended scheme is nanofiltration + chlorination.
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Cloro/farmacología , Desinfectantes/farmacología , Enterobacteriaceae , Enterococcus , Ácido Peracético/farmacología , Rayos Ultravioleta , Contaminantes del Agua , Purificación del Agua/métodos , Recuento de Colonia Microbiana , Desinfección/métodos , Enterobacteriaceae/efectos de los fármacos , Enterobacteriaceae/aislamiento & purificación , Enterobacteriaceae/efectos de la radiación , Enterococcus/efectos de los fármacos , Enterococcus/aislamiento & purificación , Enterococcus/efectos de la radiación , México , Trihalometanos/análisis , Ultrafiltración , Contaminantes del Agua/aislamiento & purificación , Contaminantes del Agua/efectos de la radiación , Abastecimiento de AguaRESUMEN
The influence of the inlet positions on the flow behavior inside a photoreactor has been studied using colored tracer and radiotracer investigations. The photoreactor for water disinfection is a tubular reactor inside which UV emitting lamps are placed. The key to its good performance is a combination of optimum irradiation dose and fluid residence time distributions (RTD). The inlet system is one of the better possibilities of controling the fluid RTD. Three configurations have been tested. In the first step, colored tracer experiments help us to raise the mean trends of the flow behavior for the different configurations. When the inlet is located at the central bottom of the reactor, the flow is closed to a perfect mixing whereas lateral inlets lead to a plug flow with axial dispersion behavior. RTD measurements using radiotracer was carried out in a wide range of flowrates. The axial dispersion coefficient increases linearly with the Reynolds number. It is lower when the lateral inlet is divided in three inlets uniformly distributed around the bottom of the reactor. This paper shows the usefulness of radioactive isotopes as tracers in the field of wastewater treatment.
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Fotoquímica/instrumentación , Reología/métodos , Rayos Ultravioleta , Purificación del Agua/instrumentación , Purificación del Agua/métodos , Colorantes , Enterobacteriaceae/efectos de la radiación , Escherichia coli/efectos de la radiación , Modelos Teóricos , RadioisótoposRESUMEN
Irradiation of sewage sludge reduces pathogens and can hydrolyze or destroy organic molecules. The effect of irradiation of sewage sludge on C and N dynamics in arable soil and possible interference with toxic organic compounds was investigated in soil microcosms using a clay soil. The soil was treated with phenanthrene and anthracene, with and without irradiated and non-irradiated sewage sludge amendment. All the treated soils were incubated for 182 days at 25 degrees C. The CO2 production and dynamics of inorganic N (NH4+, NO2- and NO3-) were monitored. Addition of sewage sludge (0.023 g g(-1) soil), anthracene or phenanthrene (10.0 microg g(-1) soil dissolved in methanol), and methanol (10 mg g(-1) soil) to soil had a significant effect on CO2 production compared to the control. However, there were no significant differences between soil treated with irradiated and non-irradiated sewage sludge. Irradiated sewage sludge increased the C and N mineralization of anthracene amended soils to a greater extend than in phenanthrene amended soils. Nitrification was inhibited for 28 days in soil treated with either methanol, anthracene and phenanthrene. Application of sewage sludge reduced such toxicity effects after 28 days incubation.
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Silicatos de Aluminio/efectos de la radiación , Antracenos/química , Dióxido de Carbono/metabolismo , Compuestos de Nitrógeno/metabolismo , Fenantrenos/química , Aguas del Alcantarillado/química , Microbiología del Suelo , Silicatos de Aluminio/química , Antracenos/metabolismo , Carbono/química , Carbono/metabolismo , Arcilla , Enterobacteriaceae/metabolismo , Enterobacteriaceae/efectos de la radiación , Metanol/metabolismo , Minerales/química , Minerales/metabolismo , Nitrógeno/química , Nitrógeno/metabolismo , Compuestos de Nitrógeno/química , Fenantrenos/metabolismo , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Aguas del Alcantarillado/microbiología , Suelo/análisisRESUMEN
A boldina é um alcalóide aporfina geralmente encontrado nas plantas das famílilas Magnoliaceae, Annonaceae, Rhamnaceae e Monimiaceae. No presente trabalho foi proposta a realizaçäo de alguns ensaios com o objetivo de avaliar a açäo protetora da boldina em culturas de Yersinia enterocolitica e Escherichia coli HB 101 submetidas a açäo fotoprotetora desse alcalóide somente quando as células foram mantidas em condiçöes de liquid holding.