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1.
Appl Microbiol Biotechnol ; 106(8): 3153-3171, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35396956

RESUMO

The Tsukamurella tyrosinosolvens PS2 strain was isolated from hydrocarbons-contaminated petrochemical sludge as a long chain alkane-utilizing bacteria. Complete genome analysis showed the presence of two alkane oxidation systems: alkane 1-monooxygenase (alkB) and cytochrome P450 monooxygenase (P450) genes with established high homology to the well-known alkane-degrading actinobacteria. According to the comparative genome analysis, both systems have a wide distribution among environmental and clinical isolates of the genus Tsukamurella and other members of Actinobacteria. We compared the expression of different proteins during the growth of Tsukamurella on sucrose and on hexadecane. Both alkane monooxygenases were upregulated on hexadecane: AlkB-up to 2.5 times, P450-up to 276 times. All proteins of the hexadecane oxidation pathway to acetyl-CoA were also upregulated. Accompanying proteins for alkane degradation involved in biosurfactant synthesis and transport of organic and inorganic molecules were increased. The change in the carbon source affected the pathways for the regulation of translation and transcription. The proteomic profile showed that hexadecane is an adverse factor causing activation of general and universal stress proteins as well as shock and resistance proteins. Differently expressed proteins of Tsukamurella tyrosinosolvens PS2 shed light on the alkane degradation in other members of Actinobacteria class. KEY POINTS: • alkB and P450 systems have a wide distribution among the genus Tsukamurella. • alkB and P450 systems have coexpression with the predominant role of P450 protein. • Hexadecane causes significant changes in bacterial proteome.


Assuntos
Actinomycetales , Proteômica , Actinobacteria , Actinomycetales/genética , Actinomycetales/metabolismo , Alcanos/metabolismo , Bactérias/metabolismo , Biodegradação Ambiental , Citocromo P-450 CYP4A/genética , Citocromo P-450 CYP4A/metabolismo
2.
Artigo em Inglês | MEDLINE | ID: mdl-32406803

RESUMO

The ability of white-rot fungus, Trametes hirsuta AK04, to utilize phenolics as single and mixed substrates was determined in mineral medium and palm oil mill effluent (POME). The strain AK04 was able to rapidly metabolize all ten phenolics as single and mixed substrates at all test concentrations. With single substrates, between 78 and 98% removal was achieved within seven days. The biomass yield increased with increasing concentration from 100 to 500 mg L-1 but slightly decreased when the concentration was increased up to 1,000 mg L-1. When fitted to a Haldane model, the groups of benzoic and cinnamic acid derivatives gave significantly higher maximum specific growth rates than other phenolics. Phenol exhibited the lowest affinity and highest inhibitory effects on fungal metabolism. In mixed substrates, the total concentration ranges of phenolics mixtures between 1,000 and 6,000 mg L-1 did not affect the fungal growth rate and the strain AK04 showed a high degree of resistance to their toxic effects. The addition of glucose and yeast extract enhanced the degradation rates of individual phenolics in the substrate mixtures, demonstrating the advantage of this strain for treating complex media, such as industrial wastewater.


Assuntos
Resíduos Industriais/análise , Óleo de Palmeira , Fenóis/metabolismo , Trametes/crescimento & desenvolvimento , Águas Residuárias/química , Poluentes Químicos da Água/análise , Biodegradação Ambiental , Biomassa , Cinética , Modelos Teóricos , Fenóis/análise , Tailândia , Trametes/metabolismo , Purificação da Água/métodos
3.
Wien Med Wochenschr ; 165(3-4): 71-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25572549

RESUMO

Adherence to medical advice, driven by high patient motivation, could lead to a significant reduction in risk factors during cardiac rehabilitation.During a 1-year period, 9082 patients were admitted to six cardiac rehabilitation centres. A total of 1195 highly motivated subjects were selected based on their reliable completion of a survey regarding cardiac risk factors.Study subjects had lower risk factors at baseline compared with a contemporary Austrian database. At discharge from the rehabilitation programme subjects showed further reductions in median weight, low-density lipoprotein cholesterol, blood pressure and resting pulse rate (due to increased levels of daily exercise). Smoking also decreased. Most of these changes were still significant after 1 year.The risk factors in these highly motivated patients were low to begin with and were further reduced by an inpatient rehabilitation programme. The content and method of delivery of this programme seem to be effective. Efforts should focus on increasing motivation.


Assuntos
Doença das Coronárias/psicologia , Doença das Coronárias/reabilitação , Motivação , Admissão do Paciente , Cooperação do Paciente/psicologia , Idoso , Áustria , Estudos de Coortes , Terapia Combinada , Feminino , Seguimentos , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Planejamento de Assistência ao Paciente , Recidiva , Centros de Reabilitação , Fatores de Risco , Resultado do Tratamento
4.
Eur Spine J ; 23(4): 779-85, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24413743

RESUMO

PURPOSE: This longitudinal study investigated long-term effects of a multidisciplinary rehabilitation program consisting of resistance and sensorimotor training, patient education, and stress management over 6 months in patients with chronic low back pain. METHODS: Ninety-six patients with chronic recurrent low back pain performed a multidisciplinary rehabilitation program. We assessed pain-free lumbar spine range of motion (ROM), strength of the lumbar extensor muscles, and pain by visual analog scale (VAS). Furthermore, the Roland-Morris (RM) questionnaire and SF-36 were used. The examinations were performed before and after rehabilitation, and a long-term follow-up was performed after 18 months. RESULTS: All outcome measurements (ROM, VAS, RM, muscle strength, and SF-36 scores) improved significantly from baseline to the post-rehabilitation evaluation. These improvements were found to persist until a follow-up evaluation 18 months after cessation of the intervention. CONCLUSIONS: Our findings confirm the results of former studies evaluating the short-term effects of multidisciplinary rehabilitation programs. In addition, our data demonstrate that well-balanced outpatient rehabilitation programs may induce persistent improvements in muscle strength, pain, function and quality of life in patients with chronic low back pain.


Assuntos
Assistência Ambulatorial/métodos , Dor Crônica/reabilitação , Dor Lombar/reabilitação , Serviços de Saúde Mental , Educação de Pacientes como Assunto , Treinamento Resistido , Adulto , Terapia Combinada , Feminino , Humanos , Comunicação Interdisciplinar , Estudos Longitudinais , Vértebras Lombares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Limitação da Mobilidade , Força Muscular , Medição da Dor , Qualidade de Vida , Amplitude de Movimento Articular , Recidiva , Inquéritos e Questionários , Resultado do Tratamento
5.
Biotechnol Biotechnol Equip ; 28(4): 747-752, 2014 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-26740774

RESUMO

Antibacterial SiO2 hybrid materials based on tetraethyl orthosilicate (TEOS), hydroxypropylmethylcellulose (HPMC) and silver were prepared by the sol-gel method. The content of cellulose derivate was 5 wt% and the silver concentration varied from 0.5 wt% to 2.5 wt%. The amorphous nature, morphology and antibacterial behaviour were studied. Fourier transform infrared (FTIR) spectra of the hybrids showed characteristic peaks for SiO2 network. Scanning electron microscope (SEM) analysis confirmed the formation of spherically shaped silver nanoparticles with a size of 30 nm on the matrix surfaces. Bacillus subtilis and Escherichia coli K12 were used as model microorganisms. The hybrid materials demonstrated bacteriostatic and bactericidal effect on the tested bacteria. Highest sensitivity to the obtained hybrids was observed in B. subtilis with significant lag-phase delay and biggest inhibition zone sizes.

6.
Wien Med Wochenschr ; 162(15-16): 330-6, 2012 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-22688619

RESUMO

BACKGROUND: Aim of the study was to evaluate the effects of supervised exercise training for peripheral arterial disease (PAD) on walking speed, claudication distance and quality of life. METHODS AND RESULTS: Ninety-four patients in stage IIa/IIb according to Fontaine underwent a six-month exercise training at the Center for Outpatient Rehabilitation Vienna (ZAW). Walking speed and Absolute Claudication Distance (ACD) improved significantly (p < 0,001 and p = 0,007 respectively). Increase of the Initial Claudication Distance (ICD) did not reach statistical significance (p = 0,14). Quality of life, as assessed by the questionnaire "PLC" manifested no significant change. CONCLUSIONS: The exercise training achieved considerable effects on walking speed and claudication distance. Despite these improvements, patient's quality of life revealed no relevant change. This outcome could be explained by the fact that aspects of physical functioning relevant to patients with claudicatio intermittens may be underrepresented in the PLC-questionnaire core module.


Assuntos
Arteriopatias Oclusivas/reabilitação , Exercício Físico , Claudicação Intermitente/reabilitação , Doença Arterial Periférica/reabilitação , Educação Física e Treinamento , Qualidade de Vida/psicologia , Caminhada , Idoso , Assistência Ambulatorial , Arteriopatias Oclusivas/psicologia , Áustria , Doença das Coronárias/psicologia , Doença das Coronárias/reabilitação , Progressão da Doença , Feminino , Humanos , Claudicação Intermitente/psicologia , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Avaliação de Processos e Resultados em Cuidados de Saúde , Pacientes Desistentes do Tratamento , Educação de Pacientes como Assunto , Doença Arterial Periférica/psicologia , Resistência Física , Modalidades de Fisioterapia , Treinamento Resistido
7.
Environ Sci Pollut Res Int ; 29(5): 7559-7572, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34480307

RESUMO

The dephenolization of palm oil mill effluent (POME) with oil palm fiber-immobilized Trametes hirsuta AK 04 was conducted in a temporary immersion bioreactor to reduce the inhibitory effects of phenolics in anaerobic digestion. Longer immersion times provided greater removal of phenolics due to a higher release of manganese peroxidase. The most effective dephenolization was observed at 6 h immersed and 2 h non-immersed time (immersion ratio 6/8) with maximum removal of 85% from 1277 mg L-1 of phenolics in 4 days. The immobilized fungus maintained its high activity during multiple repeated batch treatments. The pretreated POME of 2 h showed higher methane yields compared with the untreated POME substrate. The methane yields increased with increasing pretreatment time and dephenolization levels. The results suggested that an increased abundance of methanogens was associated with the detoxification of phenolics. The fungal biomass contained crude protein, amino acids, and essential phenolics, which can be used as animal feed supplements.


Assuntos
Biocombustíveis , Trametes , Animais , Reatores Biológicos , Imersão , Resíduos Industriais/análise , Óleo de Palmeira , Óleos de Plantas , Polyporaceae , Eliminação de Resíduos Líquidos
8.
J Med Chem ; 65(9): 6903-6925, 2022 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-35500229

RESUMO

New antibiotics with either a novel mode of action or novel mode of inhibition are urgently needed to overcome the threat of drug-resistant tuberculosis (TB). The present study profiles new spiropyrimidinetriones (SPTs), DNA gyrase inhibitors having activity against drug-resistant Mycobacterium tuberculosis (Mtb), the causative agent of TB. While the clinical candidate zoliflodacin has progressed to phase 3 trials for the treatment of gonorrhea, compounds herein demonstrated higher inhibitory potency against Mtb DNA gyrase (e.g., compound 42 with IC50 = 2.0) and lower Mtb minimum inhibitor concentrations (0.49 µM for 42). Notably, 42 and analogues showed selective Mtb activity relative to representative Gram-positive and Gram-negative bacteria. DNA gyrase inhibition was shown to involve stabilization of double-cleaved DNA, while on-target activity was supported by hypersensitivity against a gyrA hypomorph. Finally, a docking model for SPTs with Mtb DNA gyrase was developed, and a structural hypothesis was built for structure-activity relationship expansion.


Assuntos
Mycobacterium tuberculosis , Inibidores da Topoisomerase II , Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antituberculosos/química , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , DNA Girase/genética , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Testes de Sensibilidade Microbiana , Inibidores da Topoisomerase II/química , Inibidores da Topoisomerase II/farmacologia , Inibidores da Topoisomerase II/uso terapêutico
9.
ACS Infect Dis ; 8(11): 2315-2326, 2022 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-36325756

RESUMO

Alternative mode-of-inhibition of clinically validated targets is an effective strategy for circumventing existing clinical drug resistance. Herein, we report 1,3-diarylpyrazolyl-acylsulfonamides as potent inhibitors of HadAB/BC, a 3-hydroxyl-ACP dehydratase complex required to iteratively elongate the meromycolate chain of mycolic acids in Mycobacterium tuberculosis (Mtb). Mutations in compound 1-resistant Mtb mutants mapped to HadC (Rv0637; K157R), while chemoproteomics confirmed the compound's binding to HadA (Rv0635), HadB (Rv0636), and HadC. The compounds effectively inhibited the HadAB and HadBC enzyme activities and affected mycolic acid biosynthesis in Mtb, in a concentration-dependent manner. Unlike known 3-hydroxyl-ACP dehydratase complex inhibitors of clinical significance, isoxyl and thioacetazone, 1,3-diarylpyrazolyl-acylsulfonamides did not require activation by EthA and thus are not liable to EthA-mediated resistance. Further, the crystal structure of a key compound in a complex with Mtb HadAB revealed unique binding interactions within the active site of HadAB, providing a useful tool for further structure-based optimization of the series.


Assuntos
Mycobacterium tuberculosis , Tioacetazona , Proteínas de Bactérias/metabolismo , Ácidos Micólicos/química , Tioacetazona/metabolismo , Tioacetazona/farmacologia , Hidroliases/química , Hidroliases/metabolismo , Hidroliases/farmacologia
10.
Eur J Cardiovasc Prev Rehabil ; 18(6): 843-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21450590

RESUMO

BACKGROUND: Initiation of a long-term improvement of cardiac risk factors is one of the major aims of a cardiac rehabilitation/secondary prevention programme. METHODS AND PARTICIPANTS: The Health Guide collected data in terms of cardiac risk factors: blood pressure, resting pulse, total cholesterol, LDL cholesterol, body weight, physical activity and number of cigarettes at admission and discharge after a stationary rehabilitation programme and every 3 months. After 12 months the Health Guides were returned. In the prospective study 2664 patients (71.8% men, age: MV = 62.94 years, SD = 9.96; 28% women, MV = 67.59 years, SD = 9.53) with coronary heart disease (CHD) were included. RESULTS: All cardiac risk factors documented by the Health Guide improved during the cardiac rehabilitation programme. After one year, risk factors were significantly lower than at admission, apart from total cholesterol. The individual goal in terms of body weight and LDL cholesterol was partially achieved after the rehabilitation programme and maintained after one year. In the investigation years, 2004-2007, the cholesterol and blood pressure were significantly lower than in the years 2000-2003. CONCLUSION: The use of a Health Guide resulted in an improved long-term effect of a cardiac rehabilitation/secondary prevention programme. It is a simple and cheap intervention and can help in the guidance of the patients.


Assuntos
Doença das Coronárias/reabilitação , Pacientes Internados , Prevenção Secundária , Idoso , Áustria , Pressão Sanguínea , Peso Corporal , Doença das Coronárias/sangue , Doença das Coronárias/diagnóstico , Doença das Coronárias/etiologia , Doença das Coronárias/fisiopatologia , Dislipidemias/sangue , Dislipidemias/complicações , Dislipidemias/terapia , Feminino , Humanos , Hipertensão/complicações , Hipertensão/fisiopatologia , Hipertensão/terapia , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Atividade Motora , Análise Multivariada , Obesidade/complicações , Obesidade/terapia , Projetos Piloto , Avaliação de Programas e Projetos de Saúde , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Fumar/efeitos adversos , Prevenção do Hábito de Fumar , Fatores de Tempo , Resultado do Tratamento
11.
Bioprocess Biosyst Eng ; 34(8): 913-21, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21487698

RESUMO

A novel biotechnological process for the production of high-quality flax fibers was developed. In this process, decorticated fibers from green flax were washed with 0.5% soda solution and treated with the pectinolytic strain Geobacillus thermoglucosidasius PB94A. Before drying the fibers, they were treated with the textile softener Adulcinol BUN. If the fibers contained contaminant shives, a bleaching step with hydrogen peroxide was performed before the softener treatment. In experiments where fibers were treated by the new process, and in which the bacterial solutions were reused seven times, the fiber quality was similar in all batches. The resolution of the treated fibers was 2.7 ± 0.4 and the fineness was 11.1 ± 1.1 dtex, while the starting material had a resolution of 7.3 and a fineness of 37 dtex. The new biotechnological treatment eliminates the weather-associated risks of the traditional fiber retting completely and produces consistently high-quality fibers that can be used to produce fine linen yarns.


Assuntos
Biotecnologia/métodos , Linho/química , Geobacillus/enzimologia , Pectinas/química , Polissacarídeo-Liases/química , Geobacillus/isolamento & purificação , Pectinas/biossíntese , Poligalacturonase/química , Poligalacturonase/metabolismo , Polissacarídeo-Liases/biossíntese , Têxteis
12.
Wien Med Wochenschr ; 161(9-10): 263-71, 2011 May.
Artigo em Alemão | MEDLINE | ID: mdl-21638217

RESUMO

BACKGROUND: This retrospective cohort study analyses effectiveness and sustainability of the current cardiac Phase III (Ph-III) rehabilitation program, provided by the Centre for Outpatient Rehabilitation (ZAR). METHODS: We analysed routine data of 451 intervention group patients (IG, with Ph-III) and 781 control group patients (KG, without Ph-III). RESULTS: In a median observation period of 2.73 years we found 30% less cases of death in the IG based on the mortality risk observed in the KG (rr = 0.70; p = 0.108). However, we registered more re-events, mainly stent implantations in the IG (rr = 1.34; p = 0.095). Groups differed in some baseline characteristics. CONCLUSIONS: The lower mortality risk by trend might be explained by the close-meshed care, the IG patients' more health conscious behaviour or a selection bias of the KG (e.g. more severe underlying disease). The causality of potential positive effects cannot be confirmed by this study because of the study design.


Assuntos
Assistência Ambulatorial , Angioplastia Coronária com Balão/reabilitação , Ponte de Artéria Coronária/reabilitação , Infarto do Miocárdio/reabilitação , Isquemia Miocárdica/reabilitação , Stents , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Áustria , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/mortalidade , Isquemia Miocárdica/mortalidade , Avaliação de Processos e Resultados em Cuidados de Saúde , Estudos Retrospectivos , Análise de Sobrevida , Adulto Jovem
13.
J Med Chem ; 64(13): 9444-9457, 2021 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-34138573

RESUMO

Screening of a library of small polar molecules against Mycobacterium tuberculosis (Mtb) led to the identification of a potent benzoheterocyclic oxime carbamate hit series. This series was subjected to medicinal chemistry progression underpinned by structure-activity relationship studies toward identifying a compound for proof-of-concept studies and defining a lead optimization strategy. Carbamate and free oxime frontrunner compounds with good stability in liver microsomes and no hERG channel inhibition liability were identified and evaluated in vivo for pharmacokinetic properties. Mtb-mediated permeation and metabolism studies revealed that the carbamates were acting as prodrugs. Toward mechanism of action elucidation, selected compounds were tested in biology triage assays to assess their activity against known promiscuous targets. Taken together, these data suggest a novel yet unknown mode of action for these antitubercular hits.


Assuntos
Antituberculosos/farmacologia , Carbamatos/farmacologia , Compostos Heterocíclicos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Oximas/farmacologia , Antituberculosos/química , Antituberculosos/metabolismo , Carbamatos/química , Carbamatos/metabolismo , Relação Dose-Resposta a Droga , Compostos Heterocíclicos/química , Compostos Heterocíclicos/metabolismo , Testes de Sensibilidade Microbiana , Estrutura Molecular , Mycobacterium tuberculosis/metabolismo , Oximas/química , Oximas/metabolismo , Relação Estrutura-Atividade
14.
J Med Chem ; 64(17): 12790-12807, 2021 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-34414766

RESUMO

Phenotypic whole cell high-throughput screening of a ∼150,000 diverse set of compounds against Mycobacterium tuberculosis (Mtb) in cholesterol-containing media identified 1,3-diarylpyrazolyl-acylsulfonamide 1 as a moderately active hit. Structure-activity relationship (SAR) studies demonstrated a clear scope to improve whole cell potency to MIC values of <0.5 µM, and a plausible pharmacophore model was developed to describe the chemical space of active compounds. Compounds are bactericidal in vitro against replicating Mtb and retained activity against multidrug-resistant clinical isolates. Initial biology triage assays indicated cell wall biosynthesis as a plausible mode-of-action for the series. However, no cross-resistance with known cell wall targets such as MmpL3, DprE1, InhA, and EthA was detected, suggesting a potentially novel mode-of-action or inhibition. The in vitro and in vivo drug metabolism and pharmacokinetics profiles of several active compounds from the series were established leading to the identification of a compound for in vivo efficacy proof-of-concept studies.


Assuntos
Antituberculosos/farmacologia , Parede Celular/metabolismo , Mycobacterium tuberculosis/efeitos dos fármacos , Sulfonamidas/farmacologia , Antituberculosos/síntese química , Antituberculosos/química , Descoberta de Drogas , Células Hep G2 , Humanos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Mycobacterium tuberculosis/metabolismo , Relação Estrutura-Atividade , Sulfonamidas/química
15.
Appl Environ Microbiol ; 76(14): 4684-90, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20472723

RESUMO

The cometabolic degradation of trichloroethene (TCE) by Rhodococcus sp. L4 was limited by the loss of enzyme activity during TCE transformation. This problem was overcome by repeated addition of inducing substrates, such as cumene, limonene, or cumin aldehyde, to the cells. Alternatively, Rhodococcus sp. L4 was immobilized on plant materials which contain those inducers in their essential oils. Cumin seeds were the most suitable immobilizing material, and the immobilized cells tolerated up to 68 muM TCE and degraded TCE continuously. The activity of immobilized cells, which had been inactivated partially during TCE degradation, could be reactivated by incubation in mineral salts medium without TCE. These findings demonstrate that immobilization of Rhodococcus sp. L4 on plant materials rich in essential oils is a promising method for efficient cometabolic degradation of TCE.


Assuntos
Cuminum/microbiologia , Óleos Voláteis/metabolismo , Rhodococcus/metabolismo , Tricloroetileno/metabolismo , Benzaldeídos/metabolismo , Derivados de Benzeno/metabolismo , Biotransformação , Células Imobilizadas , Meios de Cultura/química , Cicloexenos/metabolismo , Cimenos , Limoneno , Minerais/metabolismo , Sementes/microbiologia , Terpenos/metabolismo
16.
Appl Microbiol Biotechnol ; 85(5): 1315-20, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19957079

RESUMO

Pyrazines are a class of compounds that occur almost ubiquitously in nature. Pyrazines can be synthesised chemically or biologically, and are used as flavouring additives. The major formation of pyrazines occurs during heating of food. There is very little information available on the degradation of these compounds. In humans and animals, pyrazines are excreted as glucuronates or bound to glutathione via the kidney after hydroxylation, but the pyrazine ring is not cleaved. Bacteria have been isolated, which are able to use various substituted pyrazines as a sole carbon and energy source. In a few cases, the initial metabolites have been characterised; however, the mechanism of ring cleavage and the further degradation pathways are still unknown and await further investigation.


Assuntos
Bactérias/metabolismo , Biodegradação Ambiental , Pirazinas/metabolismo , Animais , Carbono/metabolismo , Aromatizantes/química , Aromatizantes/metabolismo , Humanos , Hidroxilação , Resíduos Industriais , Estrutura Molecular , Odorantes , Pirazinas/química , Pirazinas/toxicidade
17.
Sci Rep ; 10(1): 7079, 2020 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-32341378

RESUMO

The Deepwater Horizon incident in the Gulf of Mexico in 2010 released an unprecedented amount of petroleum hydrocarbons 1500 meters below the sea surface. Few studies have considered the influence of hydrostatic pressure on bacterial community development and activity during such spills. The goal of this study was to investigate the response of indigenous sediment microbial communities to the combination of increased pressure, hydrocarbons and dispersant. Deep-sea sediment samples collected from the northern Gulf of Mexico were incubated at atmospheric pressure (0.1 MPa) and at elevated pressure (10 MPa), with and without the addition of crude oil and dispersant. After incubations at 4 °C for 7 days, Colwellia and Psychrobium were highly abundant in all samples. Pressure differentially impacted members of the Alteromonadales. The influences of pressure on the composition of bacterial communities were most pronounced when dispersant was added to the incubations. Moritella and Thalassotalea were greatly stimulated by the addition of dispersant, suggesting their roles in dispersant biodegradation. However, Moritella was negatively impacted by increasing pressure. The presence of dispersant was shown to decrease the relative abundance of a known hydrocarbon degrader, Cycloclasticus, while increasing pressure increased its relative abundance. This study highlights the significant influence of pressure on the development of microbial communities in the presence of oil and dispersant during oil spills and related response strategies in the deep sea.


Assuntos
Bactérias , Consórcios Microbianos , Poluição por Petróleo , Microbiologia da Água , Poluição Química da Água , Bactérias/classificação , Bactérias/crescimento & desenvolvimento , Biodegradação Ambiental , Golfo do México
18.
Mar Pollut Bull ; 150: 110683, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31753565

RESUMO

A new Rhodococcus strain, capable of degrading crude oil, was isolated from the Gulf of Mexico deep-sea sediment and was investigated for its biodegradation characteristics under atmospheric as well as under deep-sea pressure (1500 m = 15 MPa). Additionally, the effect of dispersant (Corexit EC9500A) addition was studied. Rhodococcus sp. PC20 was shown to degrade 60.5 ±â€¯10.7% of the saturated and aromatic fraction of crude oil at atmospheric pressure and 74.2 ±â€¯9.1% at deep-sea level pressure within 96 h. Degradation rates, especially for monoaromatic hydrocarbons, were significantly higher at elevated pressure compared to atmospheric pressure. This study found a growth inhibiting effect at a dispersant to oil ratio of 1:100 and higher. This effect of the dispersant was enhanced when elevated pressure was applied.


Assuntos
Biodegradação Ambiental , Poluição por Petróleo , Petróleo/metabolismo , Rhodococcus/fisiologia , Sedimentos Geológicos/microbiologia , Golfo do México , Rhodococcus/isolamento & purificação , Água do Mar/microbiologia , Microbiologia da Água
19.
Health Qual Life Outcomes ; 7: 99, 2009 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-19995445

RESUMO

BACKGROUND: The goal of cardiac rehabilitation programs is not only to prolong life but also to improve physical functioning, symptoms, well-being, and health-related quality of life (HRQL). The aim of this study was to document the long-term effect of a 1-month inpatient cardiac rehabilitation intervention on HRQL in Austria. METHODS: Patients (N = 487, 64.7% male, age 60.9 +/- 12.5 SD years) after myocardial infarction, with or without percutaneous interventions, coronary artery bypass grafting or valve surgery underwent inpatient cardiac rehabilitation and were included in this long-term observational study (two years follow-up). HRQL was measured with both the MacNew Heart Disease Quality of Life Instrument [MacNew] and EuroQoL-5D [EQ-5D]. RESULTS: All MacNew scale scores improved significantly (p < 0.001) and exceeded the minimal important difference (0.5 MacNew points) by the end of rehabilitation. Although all MacNew scale scores deteriorated significantly over the two year follow-up period (p < .001), all MacNew scale scores still remained significantly higher than the pre-rehabilitation values. The mean improvement after two years in the MacNew social scale exceeded the minimal important difference while MacNew scale scores greater than the minimal important difference were reported by 40-49% of the patients.Two years after rehabilitation the mean improvement in the EQ-5D Visual Analogue Scale score was not significant with no significant change in the proportion of patients reporting problems at this time. CONCLUSION: These findings provide a first indication that two years following inpatient cardiac rehabilitation in Austria, the long-term improvements in HRQL are statistically significant and clinically relevant for almost 50% of the patients. Future controlled randomized trials comparing different cardiac rehabilitation programs are needed.


Assuntos
Cardiopatias/reabilitação , Avaliação de Resultados em Cuidados de Saúde/métodos , Psicometria/instrumentação , Qualidade de Vida , Inquéritos e Questionários , Adulto , Idoso , Áustria , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
Biodegradation ; 20(2): 281-91, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18846429

RESUMO

Cometabolic degradation of TCE by toluene-degrading bacteria has the potential for being a cost-effective bioremediation technology. However, the application of toluene may pose environmental problems. In this study, several plant essential oils and their components were examined as alternative inducer for TCE cometabolic degradation in a toluene-degrading bacterium, Rhodococcus sp. L4. Using the initial TCE concentration of 80 microM, lemon and lemongrass oil-grown cells were capable of 20 +/- 6% and 27 +/- 8% TCE degradation, which were lower than that of toluene-grown cells (57 +/- 5%). The ability of TCE degradation increased to 36 +/- 6% when the bacterium was induced with cumin oil. The induction of TCE-degrading enzymes was suggested to be due to the presence of citral, cumin aldehyde, cumene, and limonene in these essential oils. In particular, the efficiency of cumin aldehyde and cumene as inducers for TCE cometabolic degradation was similar to toluene. TCE transformation capacities (T (c)) for these induced cells were between 9.4 and 15.1 microg of TCE mg cells(-1), which were similar to the known toluene, phenol, propane or ammonia degraders. Since these plant essential oils are abundant and considered non-toxic to humans, they may be applied to stimulate TCE degradation in the environment.


Assuntos
Óleos Voláteis/metabolismo , Plantas/metabolismo , Rhodococcus/metabolismo , Tricloroetileno/metabolismo , Rhodococcus/crescimento & desenvolvimento
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