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1.
Ned Tijdschr Geneeskd ; 1662022 02 16.
Artigo em Holandês | MEDLINE | ID: mdl-35499767

RESUMO

Graves' orbitopathy may cause multiple symptoms, such as proptosis, redness or inflammation of the conjunctiva, excessive tearing, swelling of the eyelids and pain. Smoking, male gender and old age are significant risk factors for a more severe and active disease.


Assuntos
Exoftalmia , Oftalmopatia de Graves , Doenças do Aparelho Lacrimal , Exoftalmia/complicações , Exoftalmia/etiologia , Oftalmopatia de Graves/diagnóstico , Oftalmopatia de Graves/etiologia , Humanos , Inflamação/complicações , Masculino
4.
Trends Cogn Sci ; 22(4): 277-279, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29571663

RESUMO

Until recently, many psychologists were skeptical that young children cared about reputation. New evidence suggests that by age five, children begin to understand the broad importance of reputation and to engage in surprisingly sophisticated impression management. These findings prompt exciting new questions about the development of a fundamental social competency.


Assuntos
Comportamento Infantil , Desenvolvimento Infantil , Relações Interpessoais , Comportamento Social , Percepção Social , Criança , Comportamento Infantil/psicologia , Pré-Escolar , Humanos
5.
Water Sci Technol ; 76(5-6): 1418-1428, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28953468

RESUMO

Duckweed offers the promise of a co-benefit culture combining water purification with biomass production. Acinetobacter calcoaceticus P23 is a plant growth-promoting bacterium isolated from a duckweed, Lemna aequinoctialis. This study quantified its growth-promoting effect on three duckweeds (L. aoukikusa, L. minor, and Spirodela polyrhiza) in sterile Hoagland solution and evaluated its usefulness in duckweed culture under non-sterile conditions. P23 promoted growth of three duckweeds in sterile Hoagland solution at low to high nutrient concentrations (1.25-10 mg NO3-N/L and 0.25-2.0 mg PO4-P/L). It increased the biomass production of L. aequinoctialis 3.8-4.3-fold, of L. minor 2.3-3.3-fold, and of S. polyrhiza 1.4-1.5-fold after 7 days compared with noninoculated controls. P23 also increased the biomass production of L. minor 2.4-fold in pond water and 1.7-fold in secondary effluent of a sewage treatment plant under non-sterile conditions at laboratory-scale experiments. P23 rescued L. minor from growth inhibition caused by microorganisms indigenous to the pond water. The results demonstrate that the use of P23 in duckweed culture can improve the efficiency of duckweed biomass production, and a positive effect of P23 on duckweed-based wastewater treatment can be assumed.


Assuntos
Acinetobacter calcoaceticus/fisiologia , Araceae/crescimento & desenvolvimento , Araceae/microbiologia , Biomassa , Águas Residuárias , Purificação da Água/métodos , Água Doce , Desenvolvimento Vegetal , Poluentes Químicos da Água/química
6.
Water Sci Technol ; 72(8): 1294-300, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26465298

RESUMO

A novel process by using chemical leaching followed by bacterial reductive precipitation was proposed for selenium recovery from kiln powder as a byproduct of cement manufacturing. The kiln powder at a slurry concentration of 10 w/v% with 0.25 M Na2CO3 at 28°C produced wastewater containing about 30 mg-Se/L selenium. The wastewater was diluted four-fold and adjusted to pH 8.0 as preconditioning for bioreduction. A bacterial strain Pseudomonas stutzeri NT-I, capable of reducing selenate and selenite into insoluble elemental selenium, could recover about 90% selenium from the preconditioned wastewater containing selenium of 5 mg-Se/L when supplemented with lactate or glycerol. The selenium concentrations in the treated wastewater were low around the regulated effluent concentration of 0.1 mg-Se/L in Japan.


Assuntos
Pseudomonas stutzeri/metabolismo , Ácido Selênico/metabolismo , Selênio/isolamento & purificação , Precipitação Química , Resíduos Industriais , Japão , Oxirredução , Selênio/metabolismo , Compostos de Selênio , Águas Residuárias
7.
J Appl Microbiol ; 118(1): 255-66, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25362861

RESUMO

AIMS: To clarify the polyhydroxyalkanoate (PHA) accumulation potential and the PHA-accumulating microbial community structure in activated sludge in municipal wastewater treatment plants (WWTPs) and to identify their influential factors. METHODS AND RESULTS: Nine activated sludge samples were collected from municipal WWTPs employing various biological treatment processes. In acetate-fed 24-h batch experiments under aerobic and nitrogen- and phosphorus-limited conditions, polyhydroxybutyrate (PHB) content of activated sludge increased from 0-1·3 wt% to 7·9-24 wt%, with PHB yields of 0·22-0·50 C-mol 3-hydroxybutyrate (C-mol acetate)(-1). Microbial community analyses found that activated sludge samples that accumulated >20 wt% of PHB after 24-h PHA accumulation experiments had >5·0 × 10(8) copies g(-1)-mixed liquor-suspended solid of phaC genes. CONCLUSIONS: Results indicated that (i) activated sludge in municipal WWTPs can accumulate up to approx. 20 wt% of PHA without enrichment processes, (ii) PHA accumulation potential of activated sludge varied depending on the operational conditions (treatment processes) of WWTPs, and (iii) phaC gene number can provide a simple indication of PHA accumulation potential. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study to compare the PHA accumulation potential and PHA-accumulating microbial communities in activated sludge of various treatment processes. Our findings may be useful for enhancing the resource recovery potential of wastewater treatment systems.


Assuntos
Poli-Hidroxialcanoatos/análise , Esgotos/química , Esgotos/microbiologia , Instalações de Eliminação de Resíduos , Bactérias/isolamento & purificação , Bactérias/metabolismo , Poli-Hidroxialcanoatos/metabolismo
8.
Int J Oral Maxillofac Surg ; 43(9): 1082-90, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25027545

RESUMO

The aim of this study was to determine changes in overnight respiratory function and craniofacial and pharyngeal airway morphology following orthognathic surgery. The subjects were 40 patients in whom mandibular prognathism was corrected by orthognathic surgery: a one-jaw operation in 22 patients and a two-jaw operation in 18 patients. Morphological changes were studied using cone beam computed tomography immediately before surgery and at more than 6 months after surgery, and the apnoea-hypopnoea index (AHI) was measured with a portable polysomnography system. Pharyngeal airway volume was decreased significantly after surgery, especially in the one-jaw operation group. AHI was not changed significantly after surgery in either group, although AHI in one patient in the one-jaw operation group was increased to 19 events/h. There was no significant change in pharyngeal airway morphology in that patient, but he was obesity class 1 and was 54 years old. In conclusion, some patients who are obese, have a large amount of mandibular setback, and/or are of relatively advanced age may develop sleep-disordered breathing after mandibular setback; a two-jaw operation should therefore be considered in skeletal class III patients who have such risks because it decreases the amount of pharyngeal airway space reduction caused by mandibular setback surgery.


Assuntos
Má Oclusão Classe III de Angle/cirurgia , Nasofaringe/fisiopatologia , Nasofaringe/cirurgia , Procedimentos Cirúrgicos Ortognáticos/métodos , Complicações Pós-Operatórias/fisiopatologia , Prognatismo/cirurgia , Transtornos do Sono-Vigília/fisiopatologia , Adolescente , Adulto , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Masculino , Má Oclusão Classe III de Angle/diagnóstico por imagem , Pessoa de Meia-Idade , Nasofaringe/diagnóstico por imagem , Polissonografia/instrumentação , Estudos Prospectivos , Respiração , Resultado do Tratamento
9.
Am J Addict ; 22(5): 425-31, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23952886

RESUMO

BACKGROUND AND OBJECTIVES: The goal of methadone maintenance treatment (MMT) is to reduce the harm and to improve patients' quality of life (Qol). However, the Qol is also influenced by other co-occurring disorders. Data regarding the Qol and the co-occurrence of these disorders is lacking in low-middle income countries. We therefore describe the prevalence of physical, psychiatric, and drug abuse co-occurring disorders among MMT patients in Indonesia and determine the association between the severity of the co-occurring disorders and the Qol. METHODS: Data were collected in 112 injection drug abusers (IDUs) attending a MMT program in West Java, Indonesia, using validated questionnaires, medical records and laboratory testing. For comparison, 154 IDUs not enrolled in MMT were recruited by respondent driven sampling. RESULTS: The most frequent co-occurring disorders were hepatitis C (92%), HIV (77%), benzodiazepine abuse (56%), and anxiety disorders (32%). IDUs in MMT had one (26%), two (47%), or three (27%) co-occurring disorders. Higher severity in psychiatric and physical problems was associated with poorer Qol. IDUs not enrolled in MMT had similar co-occurring problems. CONCLUSIONS: The prevalence of co-occurring disorders in IDUs in Indonesia is high and they influence their Qol. SCIENTIFIC SIGNIFICANCE: Therefore, comprehensive treatment, especially focusing on the common co-occurring disorders should be provided in MMT to improve the Qol.


Assuntos
Dependência de Heroína/complicações , Tratamento de Substituição de Opiáceos/psicologia , Qualidade de Vida/psicologia , Transtornos de Ansiedade/complicações , Hepatite C/complicações , Dependência de Heroína/psicologia , Dependência de Heroína/terapia , Humanos , Indonésia , Entrevistas como Assunto , Transtornos Mentais/complicações , Transtornos Mentais/terapia , Índice de Gravidade de Doença , Transtornos Relacionados ao Uso de Substâncias/complicações , Transtornos Relacionados ao Uso de Substâncias/psicologia
10.
Water Sci Technol ; 67(11): 2637-44, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23752400

RESUMO

A co-beneficial system using constructed wetlands (CWs) planted with aquatic plants is proposed for bioethanol production and nutrient removal from wastewater. The potential for bioethanol production from aquatic plant biomass was experimentally evaluated. Water hyacinth and water lettuce were selected because of their high growth rates and easy harvestability attributable to their free-floating vegetation form. The alkaline/oxidative pretreatment was selected for improving enzymatic hydrolysis of the aquatic plants. Ethanol was produced with yields of 0.14-0.17 g-ethanol/ g-biomass in a simultaneous saccharification and fermentation mode using a recombinant Escherichia coli strain or a typical yeast strain Saccharomyces cerevisiae. Subsequently, the combined benefits of the CWs planted with the aquatic plants for bioethanol production and nutrient removal were theoretically estimated. For treating domestic wastewater at 1,100 m(3)/d, it was inferred that the anoxic-oxic activated sludge process consumes energy at 3,200 MJ/d, whereas the conventional activated sludge process followed by the CW consumes only 1,800 MJ/d with ethanol production at 115 MJ/d.


Assuntos
Araceae/metabolismo , Eichhornia/metabolismo , Etanol/metabolismo , Eliminação de Resíduos Líquidos/métodos , Escherichia coli/metabolismo , Fermentação , Nitrogênio/metabolismo , Fósforo/metabolismo , Saccharomyces cerevisiae/metabolismo , Poluentes Químicos da Água/metabolismo , Purificação da Água/métodos
11.
Water Sci Technol ; 67(12): 2868-74, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23787331

RESUMO

Retinoic acid (RA) receptor (RAR) agonists are potential teratogens to various vertebrates. Their contamination has been detected in municipal wastewater in different countries. This study involved field investigations and laboratory batch treatment experiments to elucidate the removal characteristics by activated sludge treatment of RAs (all-trans RA and 13-cis RA) and 4-oxo-RAs (4-oxo-all-trans RA and 4-oxo-13-cis RA), which were identified as major RAR agonists in municipal wastewater. Results obtained in this study show that currently employed activated sludge treatments can remove RAs, 4-oxo-RAs and overall RAR agonist contamination effectively from municipal wastewater in general, although high RAR agonistic activity might sometimes remain in the effluent. Laboratory experiments revealed that RAs were removed rapidly from the aqueous phase by adsorption to the sludge, after which they were removed further by biological and/or chemical degradation. Aside from adsorption to the sludge, 4-oxo-RAs were also apparently removed by biological and chemical degradation. Biodegradation contributed greatly to the removal. Results of additional experiments indicated that novel non-identifiable RAR agonists can occur through the biodegradation of 4-oxo-RAs by activated sludge and that they can persist for a long period.


Assuntos
Esgotos/química , Tretinoína/análogos & derivados , Eliminação de Resíduos Líquidos/métodos , Fatores de Tempo , Tretinoína/química , Poluentes Químicos da Água/química
13.
BMC Public Health ; 10: 472, 2010 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-20698979

RESUMO

BACKGROUND: Injecting drug use is an increasingly important cause of HIV transmission in most countries worldwide, especially in eastern Europe, South America, and east and southeast Asia. Among people actively injecting drugs, provision of clean needles and opioid substitution reduce HIV-transmission. However, former injecting drug users (fIDUs) are often overlooked as a high risk group for HIV transmission. We compared HIV risk behavior among current and former injecting drug users (IDUs) in Indonesia, which has a rapidly growing HIV-epidemic largely driven by injecting drug use. METHODS: Current and former IDUs were recruited by respondent driven sampling in an urban setting in Java, and interviewed regarding drug use and HIV risk behavior using the European Addiction Severity Index and the Blood Borne Virus Transmission Questionnaire. Drug use and HIV transmission risk behavior were compared between current IDUs and former IDUs, using the Mann-Whitney and Pearson Chi-square test. RESULTS: Ninety-two out of 210 participants (44%) were self reported former IDUs. Risk behavior related to sex, tattooing or piercing was common among current as well as former IDUs, 13% of former IDUs were still exposed to contaminated injecting equipment. HIV-infection was high among former (66%) and current (60%) IDUs. CONCLUSION: Former IDUs may contribute significantly to the HIV-epidemic in Indonesia, and HIV-prevention should therefore also target this group, addressing sexual and other risk behavior.


Assuntos
Infecções por HIV/transmissão , Assunção de Riscos , Abuso de Substâncias por Via Intravenosa/epidemiologia , Adulto , Patógenos Transmitidos pelo Sangue , Piercing Corporal/psicologia , Distribuição de Qui-Quadrado , Feminino , Humanos , Indonésia/epidemiologia , Entrevistas como Assunto , Masculino , Comportamento Sexual/psicologia , Estatísticas não Paramétricas , Abuso de Substâncias por Via Intravenosa/psicologia , Inquéritos e Questionários , Tatuagem/psicologia , Fatores de Tempo , População Urbana/estatística & dados numéricos
14.
Water Sci Technol ; 61(11): 2843-51, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20489257

RESUMO

In this study, the microbial community structure and carbon source utilisation profile of activated sludge samples collected from full-scale municipal wastewater treatment plants (WWTPs) operated under different conditions were characterised and compared, respectively, using terminal-restriction fragment length polymorphism (T-RFLP) analysis and Biolog assay. Samples were collected from each biological treatment tank of six conventional activated sludge, two anaerobic-oxic, two anaerobic-anoxic-oxic, and one step-aeration processes in eight full-scale WWTPs in Osaka, Japan. Results of the T-RFLP analysis of eubacterial 16S rDNA showed that microbial communities of activated sludge differed greatly among samples, and that they were affected by process-based operational conditions. In contrast, the carbon source utilisation profiles of activated sludge samples were mutually similar, but appeared to be influenced slightly by aerated conditions at each reaction tank. Similar carbon source utilisation profiles among all samples suggest that the activated sludge community possesses functions that are necessary for wastewater treatment even if the phylogenetic composition is different. Different results from the T-RFLP analysis and Biolog assay suggest that the phylogenetic composition of microbial community might not necessarily reflect the wastewater treatment functions of the activated sludge.


Assuntos
Esgotos/microbiologia , Eliminação de Resíduos Líquidos/métodos , Aerobiose , Anaerobiose , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Filogenia , Polimorfismo de Fragmento de Restrição/genética , RNA Ribossômico 16S/genética , Microbiologia da Água
15.
Water Sci Technol ; 61(2): 365-73, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20107263

RESUMO

An energy consumption model was developed for evaluating sewage sludge treatment plants (SSTPs) incorporating various treatment processes such as thickening, anaerobic digestion, dewatering, incineration, and melting. Based on data analyses from SSTPs in Osaka, Japan, electricity consumption intensities for thickening, anaerobic digestion, dewatering, incineration, and melting and heat consumption intensities for anaerobic digestion, incineration, and melting were expressed as functions of sludge-loading on each unit process. The model was applied for predicting the energy consumption and greenhouse gas (GHG) emissions of SSTPs using various treatment processes and power and heat generation processes using digestion gas. Results showed that SSTPs lacking incineration and melting processes but having power generation processes showed excess energy production at the high sludge-loading rate. Energy consumption of the SSTPs without incineration and melting processes were low, but their GHG emissions were high because of CH(4) and N(2)O emissions from sludge cake at the landfill site. Incineration and melting processes consume much energy, but have lower CH(4) and N(2)O emissions.


Assuntos
Conservação de Recursos Energéticos , Efeito Estufa , Modelos Químicos , Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Modelos Teóricos , Eliminação de Resíduos Líquidos/instrumentação
16.
Water Sci Technol ; 59(12): 2447-53, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19542651

RESUMO

Retinoic acid receptor (RAR) is a nuclear receptor involved in vertebrate morphogenesis, growth, cellular differentiation, and tissue homeostasis. Excess expression of the retinoid signaling can cause various developmental toxicities in animals and humans. We previously found that influents from sewage treatment plants (STPs) in Japan had a RAR agonistic activity and the activity cannot be removed completely by conventional biological treatments. In this study, we assessed the performance of chemical and physical sewage treatment technologies-ozonation, ultraviolet treatment, chlorination, coagulation using polyaluminium chloride (PAC) and ferric sulfate, and filtration with ultrafiltration (UF), nanofiltration (NF), and reverse osmosis (RO) membranes-in removal of RAR agonistic activity of STP effluent. All water treatment experiments were conducted in laboratory-scale reactors. The RAR agonistic activity of samples was measured using a yeast two-hybrid assay. Results showed that the effectiveness of tested technologies on the removal of RAR agonistic activity can be ranked as RO or NF > chlorination > ozonation > MF > UV > coagulation with ferric sulfate>>coagulation with PAC. Furthermore, the effectiveness of chlorination might rank lower because excess reaction might bring a side effect by producing some RAR agonistic by-product(s).


Assuntos
Receptores do Ácido Retinoico/agonistas , Esgotos , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Filtração , Halogenação , Esgotos/análise , Raios Ultravioleta , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação
17.
Water Sci Technol ; 59(2): 317-22, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19182343

RESUMO

The aim of this study was to assess the availability of the biodegradation potential of aniline and phenol as the indicator for evaluating pollutant impact on a river environment. Biodegradation tests employing river water microorganisms were carried out by a modified TOC-Handai method using aniline and phenol as substrates. Complete degradation time and half-life were determined as indicators expressing the biodegradation potential of aniline and phenol, respectively. Investigations in Lake Biwa-Yodo River basin for more than two years showed that the biodegradation potential of both compounds varied seasonally. In addition, aniline biodegradation potential seemed to be influenced by the hydraulic retention time at each sampling station, while downstream stations with large input of wastewater from the surrounding cities were divided from upstream stations by phenol biodegradation potential. Comparison of the biodegradation potential in rivers at different pollution levels also showed that polluted and less polluted rivers were clearly divided by phenol biodegradation potential. These results indicated that phenol biodegradation potential can be applied as an indicator for evaluating the soundness of river environment from the view point of ecological function.


Assuntos
Biodegradação Ambiental , Rios , Microbiologia da Água , Poluentes Químicos da Água/metabolismo , Compostos de Anilina/metabolismo , Geografia , Japão , Fenol/metabolismo
18.
Water Sci Technol ; 59(1): 97-107, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19151491

RESUMO

DNA microarray mounted 85 functional gene sequences related to carbon, nitrogen and sulphur cycles, chemical degradation, metal metabolisms, and energy flows was developed to evaluate the function and status of the environment. Total of 24 river water samples from 6 sampling stations in 2 rivers in 4 seasons were analyzed using constructed DNA microarray. The numbers and constitution of the functional genes were much affected by the seasonal change. Some of the functional genes related to methane oxidation, nitrite reduction, nitrogen fixation, aromatic compounds degradation (catechol 2,3-dioxygenase), alkane degradation (group I and III) and iron reduction were detected in most of all the samples, suggesting that these could be the general functions of the river environment. Some other functional genes related to ammonium oxidation, aromatic compounds degradation (catechol 1,2-dioxygenase) and alkane degradation (group II) can be a certain indicator for the evaluation of the environmental condition.


Assuntos
Monitoramento Ambiental/métodos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Rios , Alcanos/metabolismo , Sequência de Bases , Biodegradação Ambiental , Carbono/metabolismo , Catecol 1,2-Dioxigenase/metabolismo , Hidrocarbonetos Aromáticos/metabolismo , Metais/metabolismo , Nitritos , Nitrogênio/metabolismo , Oxirredução , Compostos de Amônio Quaternário/metabolismo , Estações do Ano , Enxofre/metabolismo , Microbiologia da Água , Poluentes Químicos da Água
19.
Water Sci Technol ; 58(5): 1095-100, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18824809

RESUMO

The presence of arsenic in groundwater has been of great public concern because of its high toxicity. For purification of arsenic-contaminated groundwater, bacterial oxidation of arsenite, As(III), with a chemical adsorption process was examined in this study. After As(III) oxidation to arsenate, As(V), arsenic is easily removable from contaminated groundwater because As(V) is more adsorptive to absorbents than As(III). By acclimation to As(III) of high concentrations, a mixed culture of heterotrophic bacteria with high As(III)-oxidizing activity was obtained from a soil sample that was free from contamination. With initial concentration up to 1,500 mg l(-1) As(III), the mixed culture showed high As(III)-oxidizing activity at pH values of 7-10 and at temperatures of 25-35 degrees C. The mixed culture contained several genera of heterotrophic As(III)-oxidizing and arsenic-tolerant bacteria: Haemophilus, Micrococcus, and Bacillus. Activated alumina was added to the basal salt medium containing 75 mg l(-1) As(III) before and after bacterial oxidation. Arsenic removal by activated alumina was greatly enhanced by bacterial oxidation of As(III) to As(V). The isotherms of As(III) and As(V) onto activated alumina verified that bacterial As(III) oxidation is a helpful pretreatment process for the conventional adsorption process for arsenic removal.


Assuntos
Arsênio/metabolismo , Bactérias Anaeróbias/metabolismo , Microbiologia da Água , Poluentes Químicos da Água/metabolismo , Arsênio/isolamento & purificação , Bactérias Anaeróbias/crescimento & desenvolvimento , Biodegradação Ambiental , Água Doce/análise , Água Doce/microbiologia , Oxirredução , Poluentes Químicos da Água/isolamento & purificação
20.
Water Sci Technol ; 58(5): 1107-12, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18824811

RESUMO

Ethidium monoazide (EMA) was used to quantify DNA selectively from viable cells with healthy membrane/cell wall system, but not from dead cells, of a target bacterium in the aquatic environment using real-time PCR. Spiking experiments to determine the EMA treatment conditions showed that EMA treatment with EMA at 10-25 microg/ml and subsequent halogen light exposure for 2 min was suitable for selective quantification of DNA from viable cells in an aquatic sample using real-time PCR coupled with EMA treatment (real-time EMA-PCR). Optimized real-time EMA-PCR was applied in combination with culture-based method and conventional real-time PCR without EMA treatment to elucidate the behavior of an Escherichia coli strain inoculated into a pond water microcosm. Quantification results obtained using real-time EMA-PCR were lower than those by conventional real-time PCR without EMA treatment and higher than those by culture-based method. The results suggest that quantification by real-time EMA-PCR seemed to represent the viable population, which would partly include viable but non-culturable state bacteria. Real-time EMA-PCR optimized here can be a useful tool for selective monitoring of the viable population of a target bacterium in the aquatic environment, and thereby contribute to assessment of potential microbial risks generated from waterborne pathogenic bacteria.


Assuntos
Azidas/química , DNA Bacteriano/genética , Viabilidade Microbiana/genética , Reação em Cadeia da Polimerase/métodos , Técnicas Bacteriológicas/métodos , DNA Bacteriano/química , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Modelos Teóricos
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