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Typically, pure niobium oxide coatings are deposited on metallic substrates, such as commercially pure Ti, Ti6Al4 V alloys, stainless steels, niobium, TiNb alloy, and Mg alloys using techniques such as sputter deposition, sol-gel deposition, anodizing, and wet plasma electrolytic oxidation. The relative advantages and limitations of these coating techniques are considered, with particular emphasis on biomedical applications. The properties of a wide range of pure and modified niobium oxide coatings are illustrated, including their thickness, morphology, microstructure, elemental composition, phase composition, surface roughness and hardness. The corrosion resistance, tribological characteristics and cell viability/proliferation of the coatings are illustrated using data from electrochemical, wear resistance and biological cell culture measurements. Critical R&D needs for the development of improved future niobium oxide coatings, in the laboratory and in practice, are highlighted.
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This study investigates the removal of Pb(II) using polymer matrix membranes, cellulose acetate/vinyl triethoxysilane modified graphene oxide and gum Arabic (GuA) membranes. These complexation-NF membranes were successfully synthesized via dissolution casting method for better transport phenomenon. The varied concentrations of GuA were induced in the polymer matrix membrane. The prepared membranes M-GuA2-M-GuA10 were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, atomic force microscope and bio-fouling studies. Thermal stability of the membranes was determined by thermogravimetric analysis under nitrogen atmosphere. Dead end nanofiltration was carried out to study the perm- selectivity of all the membranes under varied pressure and concentration of Pb(NO3)2. The complexation-NF membrane performances were significantly improved after the addition of GuA in the polymer matrix membrane system. M-GuA8 membrane showed optimum result of permeation flux 8.6 l m-2 h-1. Rejection of Pb(II) ions was observed to be around 97.6% at pH 9 for all the membranes due to electrostatic interaction between CA and Gum Arabic. Moreover, with the passage of time, the rate of adsorption was also increased up to 15.7 mg g-1 until steady state was attained. Gum Arabic modified CA membranes can open up new possibilities in enhancing the permeability, hydrophilicity and anti-fouling properties.
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OBJECTIVES: Universal test and treat (UTT) is recommended for people living with HIV (PLHIV) to reduce morbidity/mortality and minimize transmission. However, concerns exist that this strategy may lead to more crowded hospitals, longer wait times and poorer service, adversely impacting health outcomes for clients with severe disease. We assessed how UTT was related to markers of disease progression in PLHIV overall and specifically among clients with low CD4 count/high World Health Organization (WHO) stage. METHODS: The analysis was conducted using data from a stepped-wedge trial of UTT in 14 government-managed health facilities in Eswatini from 2014 to 2017. Disease progression was defined as CD4 count falling below 200 cells/µL or baseline value, > 10% weight loss, body mass index (BMI) dropping below 18.5, incident tuberculosis (TB) or HIV-related death; these outcomes also were assessed individually. We assessed multivariate Cox proportional hazard models overall and specifically among clients with CD4 count < 350 cells/µL or WHO stage 3-4 at enrolment. RESULTS: Eight hundred and seven of 3176 clients demonstrated at least one marker of disease progression over 2339 person-years of follow-up. Overall, 62.4% of clients were female; 57.2% were < 35 years old. Compared to clients not exposed to UTT, those exposed to UTT had a lower rate of disease progression overall [adjusted hazard ratio (aHR) 0.60; 95% confidence interval (CI) 0.46-0.78] and a lower rate of CD4 decline (aHR 0.40; 95% CI 0.27-0.58). When the analysis was limited to clients with CD4 count < 350 cells/µL or WHO stage 3-4, UTT was not associated with disease progression (aHR 0.92; 95% CI 0.66-1.29). CONCLUSIONS: UTT reduced HIV disease progression overall and was not detrimental for clients with more severe disease.
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Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Teste de HIV/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Fármacos Anti-HIV/administração & dosagem , Contagem de Linfócito CD4 , Progressão da Doença , Essuatíni/epidemiologia , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto JovemRESUMO
This paper reports the oxidation of Remazol black B dye by employing iron ions catalyst based gas diffusion cathodes, (GDCs). A GDC was synthesized by using a layer of carbon black and iron ions catalyst for oxygen reduction to hydrogen peroxide. The results demonstrated around 97% decolorization of Remazol black-B dye for 50 min by iron ions catalyst based GDC. The degradation study was performed under electrogenerated hydrogen peroxide at a constant voltage of - 0.6 V vs Hg/HgSO4 in which the rate of degradation was correlated with hydrogen peroxide production. Overall, the GDC's found to be effective method to degrade the dyes via electro-Fenton.
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OBJECTIVES: Current WHO guidelines recommend the treatment of all HIV-infected individuals with antiretroviral therapy (ART) to improve survival and quality of life, and decrease infection of others. MaxART is the first implementation trial of this strategy embedded within a government-managed health system, and assesses mortality as a secondary outcome. Because primary findings strongly supported scale-up of the 'treat all' strategy (hereafter Treat All), this analysis examines mortality as an additional indicator of its impact. METHODS: MaxART was conducted in 14 Eswatinian health clinics through a clinic-based stepped-wedge design, by transitioning clinics from then-national standard of care (SoC) to the Treat All intervention. All-cause, disease-related, and HIV-related mortality were analysed using the Cox proportional hazards model, censoring SoC participants at clinic transition. Median follow-up time among study participants was 292 days. There were 36/2034 deaths in SoC (1.77%) and 49/1371 deaths in Treat All (3.57%). RESULTS: Between September 2014 and August 2017, 3405 participants were enrolled. In SoC and Treat All interventions, respectively, the multivariable-adjusted 12-month all-cause mortality rates were 1.42% [95% confidence interval (CI): 0.66-2.17] and 1.60% (95% CI: 0.78-2.40), disease-related mortality rates were 1.02% (95% CI: 0.40-1.64) and 1.10% (95% CI: 0.46-1.73), and HIV-related mortality rates were 1.03% (95% CI: 0.40-1.65) and 0.99% (95% CI: 0.40-1.58). Treat All had no impact on all-cause [hazard ratio (HR) = 1.12, 95% CI: 0.58-2.18, P = 0.73], disease-related (HR = 1.04, 95% CI: 0.52-2.11, P = 0.90), or HIV-related mortality (HR = 0.93, 95% CI: 0.46-1.87, P = 0.83). CONCLUSION: There was no immediate benefit of the Treat All strategy on mortality, nor evidence of harm. Longer follow-up of participants is needed to establish long-term consequences.
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Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/mortalidade , Padrão de Cuidado/organização & administração , Adulto , Essuatíni , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade , Guias de Prática Clínica como Assunto , Resultado do Tratamento , Adulto JovemAssuntos
Anestesia Epidural/métodos , Anestesia Obstétrica/métodos , Atenção , Segurança do Paciente , Feminino , Humanos , Música , Ruído , Projetos Piloto , GravidezRESUMO
We investigated the endocarp of the fruit of Cocos nucifera (i.e., the inner coconut shell), examining the structure across multiple length scales through advanced characterization techniques and in situ testing of mechanical properties. Like many biological materials, the coconut shell possesses a hierarchical structure with distinct features at different length scales that depend on orientation and age. Aged coconut was found to have a significantly stronger (ultimate tensile strength, UTS = 48.5MPa), stiffer (Young's modulus, E = 1.92GPa), and tougher (fracture resistance (R-curve) peak of KJ = 3.2MPa m1/2) endocarp than the younger fruit for loading in the latitudinal orientation. While the mechanical properties of coconut shell were observed to improve with age, they also become more anisotropic: the young coconut shell had the same strength (17MPa) and modulus (0.64GPa) values and similar R-curves for both longitudinal and latitudinal loading configurations, whereas the old coconut had 82% higher strength for loading in the latitudinal orientation, and >50% higher crack growth toughness for cracking on the latitudinal plane. Structural aspects affecting the mechanical properties across multiple length scales with aging were identified as improved load transfer to the cellulose crystalline nanostructure (identified by synchrotron x-ray diffraction) and sclerification of the endocarp, the latter of which included closing of the cell lumens and lignification of the cell walls. The structural changes gave a denser and mechanically superior micro and nanostructure to the old coconut shell. Additionally, the development of anisotropy was attributed to the formation of an anisotropic open channel structure throughout the shell of the old coconut that affected both crack initiation during uniaxial tensile tests and the toughening mechanisms of crack trapping and deflection during crack propagation.
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Cocos , Fenômenos Mecânicos , Fenômenos BiomecânicosRESUMO
WHAT IS KNOWN ABOUT THE SUBJECT?: The Advancing Recovery in Ireland (ARI) project (Health Service Executive, 2012) promotes recovery-orientated services. A previous study of Irish mental health practitioners (Cleary & Dowling ) identified the need to improve knowledge and attitudes towards recovery. To facilitate implementation of ARI and monitor progress, this study provided a 'benchmark' of current knowledge and attitudes to recovery. WHAT THIS STUDY ADDS TO EXISTING KNOWLEDGE?: The study provides important baseline information on recovery knowledge and attitudes which can be used to assess the impact of the ARI Project. It also provides valuable information that can be compared to recovery approaches employed in other countries. Despite the increased emphasis on recovery in Ireland, knowledge and attitudes of health care practitioners towards recovery remain relatively unchanged between 2007 and 2013. Working in dual settings, being a non-nurse, and training was associated with better RKI scores. Training appears to be the strongest factor in predicting better recovery knowledge. The findings suggest that knowledge levels and attitude changes following education may not be sustained over time and ongoing training may be required. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: There is considerable scope to improve recovery knowledge. Key recommendations include the need for more recovery training, evaluate whether training translates into clinical practice, using 'Recovery Champions', introducing peer support workers and developing local policies and protocols to support recovery practice. ABSTRACT: Introduction A study of Irish mental health practitioners (Cleary & Dowling ) identified the need to improve knowledge and attitudes towards recovery. This led to the Advancing Recovery in Ireland Project (ARI) which promoted recovery-orientated services and a need to 'benchmark' progress. There is little evidence regarding the types of educational interventions that maintain positive recovery knowledge and attitudes in providers. Aim The study assessed current knowledge and attitudes to recovery. Methods The methodology of Cleary & Dowling () was replicated. A survey was administered to practitioners (n = 337) using the adapted Recovery Knowledge Inventory (RKI) (Cleary & Dowling ). Results No significant differences were found in recovery scores compared to Cleary & Dowling () or by level of experience. Working in dual settings, being a non-nurse, and training was associated with better recovery scores. Significantly more respondents had received training in recovery (40% versus 23%) compared to Cleary & Dowling (). Training appears to be the strongest factor predicting better recovery knowledge. Conclusions There is considerable scope to improve recovery knowledge. Key recommendations include the need for more recovery training, using 'Recovery Champions', introducing peer support workers and developing local policies and protocols to support recovery working.
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Atitude do Pessoal de Saúde , Conhecimentos, Atitudes e Prática em Saúde , Transtornos Mentais/reabilitação , Serviços de Saúde Mental , Reabilitação Psiquiátrica/educação , Adulto , Feminino , Seguimentos , Humanos , Irlanda , Masculino , Serviços de Saúde Mental/organização & administração , Serviços de Saúde Mental/estatística & dados numéricos , Reabilitação Psiquiátrica/estatística & dados numéricosRESUMO
Soft polyethylene oxide (PEO)/chitosan mixtures, reinforced with hard titanate nanotubes (TiNTs) by co-precipitation from aqueous solution, have been used to produce compact coatings by the 'drop-cast' method, using water soluble PEO polymer and stable, aqueous colloidal solutions of TiNTs. The effects of the nanotube concentration and their length on the hardness and modulus of the prepared composite have been studied using nanoindentation and nanoscratch techniques. The uniformity of TiNT dispersion within the polymer matrix has been studied using transmission electron microscopy (TEM). A remarkable increase in hardness and reduced Young's modulus of the composites, compared to pure polymer blends, has been observed at a TiNT concentration of 25 wt %. The short (up to 30 min) ultrasound treatment of aqueous solutions containing polymers and a colloidal TiNT mixture prior to drop casting has resulted in some improvements in both hardness and reduced Young's modulus of dry composite films, probably due to a better dispersion of ceramic nanotubes within the matrix. However, further (more than 1 h) treatment of the mixture with ultrasound resulted in a deterioration of the mechanical properties of the composite accompanied by a shortening of the nanotubes, as observed by the TEM.
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Over the past 5 years, parts of Oklahoma have experienced marked increases in the number of small- to moderate-sized earthquakes. In three study areas that encompass the vast majority of the recent seismicity, we show that the increases in seismicity follow 5- to 10-fold increases in the rates of saltwater disposal. Adjacent areas where there has been relatively little saltwater disposal have had comparatively few recent earthquakes. In the areas of seismic activity, the saltwater disposal principally comes from "produced" water, saline pore water that is coproduced with oil and then injected into deeper sedimentary formations. These formations appear to be in hydraulic communication with potentially active faults in crystalline basement, where nearly all the earthquakes are occurring. Although most of the recent earthquakes have posed little danger to the public, the possibility of triggering damaging earthquakes on potentially active basement faults cannot be discounted.
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The discovery and introduction of antimicrobial agents to clinical medicine was one of the greatest medical triumphs of the 20th century that revolutionized the treatment of bacterial infections. However, the gradual emergence of populations of antimicrobial-resistant pathogenic bacteria resulting from use, misuse, and abuse of antimicrobials has today become a major global health concern. Antimicrobial resistance (AMR) genes have been suggested to originate from environmental bacteria, as clinically relevant resistance genes have been detected on the chromosome of environmental bacteria. As only a few new antimicrobials have been developed in the last decade, the further evolution of resistance poses a serious threat to public health. Urgent measures are required not only to minimize the use of antimicrobials for prophylactic and therapeutic purposes but also to look for alternative strategies for the control of bacterial infections. This review examines the global picture of antimicrobial resistance, factors that favor its spread, strategies, and limitations for its control and the need for continuous training of all stake-holders i.e., medical, veterinary, public health, and other relevant professionals as well as human consumers, in the appropriate use of antimicrobial drugs.
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The Itwara onchocerciasis focus is located around the Itwara forest reserve in western Uganda. In 1991, annual treatments with ivermectin started in the focus. They were supplemented in 1995 by the control of the vector Simulium neavei, which was subsequently eliminated from the focus. The impact of the two interventions on the disease was assessed in 2010 by nodule palpations, examinations of skin snips by microscopy and PCR, and Ov16 recombinant ELISA. There was no evidence of any microfilaria in 688 skin snips and only 2 (0.06%) of 3316 children examined for IgG4 were slightly above the arbitrary cut off of 40. A follow up of the same children 21 months later in 2012 confirmed that both were negative for diagnostic antigen Ov-16, skin snip microscopy and PCR. Based on the World Health Organization (WHO) elimination criteria of 2001 and the Uganda onchocerciasis certification guidelines, it was concluded that the disease has disappeared from the Itwara focus after 19 years of ivermectin treatments and the elimination of the vector around 2001. Ivermectin treatments were recommended to be halted.
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Anti-Helmínticos/administração & dosagem , Erradicação de Doenças , Inseticidas/administração & dosagem , Ivermectina/administração & dosagem , Oncocercose/epidemiologia , Simuliidae/crescimento & desenvolvimento , Temefós/administração & dosagem , Animais , Anticorpos Anti-Helmínticos/sangue , Criança , Pré-Escolar , Vetores de Doenças , Humanos , Lactente , Onchocerca/isolamento & purificação , Oncocercose/tratamento farmacológico , Oncocercose/prevenção & controle , Simuliidae/efeitos dos fármacos , Pele/parasitologia , Uganda/epidemiologiaRESUMO
The performance of man-made materials can be improved by exploring new structures inspired by the architecture of biological materials. Natural materials, such as nacre (mother-of-pearl), can have outstanding mechanical properties due to their complicated architecture and hierarchical structure at the nano-, micro- and meso-levels which have evolved over millions of years. This review describes the numerous experimental methods explored to date to produce composites with structures and mechanical properties similar to those of natural nacre. The materials produced have sizes ranging from nanometres to centimetres, processing times varying from a few minutes to several months and a different range of mechanical properties that render them suitable for various applications. For the first time, these techniques have been divided into those producing bulk materials, coatings and free-standing films. This is due to the fact that the material's application strongly depends on its dimensions and different results have been reported by applying the same technique to produce materials with different sizes. The limitations and capabilities of these methodologies have been also described.
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Materiais Biomiméticos/síntese química , Moluscos/química , Nácar/síntese química , Animais , Teste de MateriaisRESUMO
This audit reviewed current practice within a rural mental health service area on the monitoring and documentation of side effects of antipsychotic depot medication. A sample of 60 case files, care plans and prescriptions were audited, which is 31% of the total number of service users receiving depot injections in the mental health service region (n= 181). The sample audited had a range of diagnoses, including: schizophrenia, schizoaffective disorder, bipolar affective disorder, depression, alcoholic hallucinosis and autism. The audit results revealed that most service users had an annual documented medical review and a documented prescription. However, only five (8%) case notes examined had documentation recorded describing the condition of the injection site, and alternation of the injection site was recorded in only 28 (47%) case notes. No case notes examined had written consent to commence treatment recorded. In 57 (95%) of case notes, no documentation of recorded information on the depot and on side effects was given. The failure to monitor and record some blood tests was partly attributed to a lack of clarity regarding whose responsibility it was. A standardized checklist has been developed as a result of the audit and this will be introduced by all teams across the service.
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Antipsicóticos/efeitos adversos , Documentação , Monitoramento de Medicamentos , Auditoria Médica , Transtornos Mentais/tratamento farmacológico , Adulto , Idoso , Antipsicóticos/administração & dosagem , Serviços Comunitários de Saúde Mental , Preparações de Ação Retardada , Feminino , Humanos , Irlanda , Masculino , Pessoa de Meia-Idade , Serviços de Saúde RuralRESUMO
Antibiotic application in plant agriculture is primarily used to control fire blight caused by Erwinia amylovora in pome fruit orchards. In order to facilitate environmental impact assessment for antibiotic applications, we developed and validated culture-independent quantitative real-time PCR multiplex assays for streptomycin (strA, strB, aadA and insertion sequence IS1133) and tetracycline (tetB, tetM and tetW) resistance elements in plant and soil samples. The qPCR were reproducible and consistent whether the DNA was extracted directly from bacteria, plant and soil samples inoculated with bacteria or soil samples prior to and after manure slurry treatment. The genes most frequently identified in soils pre- and post-slurry treatment were strB, aadA, tetB and tetM. All genes tested were detected in soils pre-slurry treatment, and a decrease in relative concentrations of tetB and the streptomycin resistance genes was observed in samples taken post-slurry treatment. These multiplex qPCR assays offer a cost-effective, reliable method for simultaneous quantification of antibiotic resistance genes in complex, environmental sample matrices.
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Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Farmacorresistência Bacteriana , Ecossistema , Reação em Cadeia da Polimerase/métodos , Estreptomicina/farmacologia , Tetraciclina/farmacologia , Agricultura/métodos , Bactérias/genética , Esterco/microbiologia , Plantas/microbiologia , Microbiologia do SoloRESUMO
Recent developments in bio-fuel cell technology are reviewed. A general introduction to bio-fuel cells, including their operating principles and applications, is provided. New materials and methods for the immobilisation of enzymes and mediators on electrodes, including the use of nanostructured electrodes are considered. Fuel, mediator and enzyme materials (anode and cathode), as well as cell configurations are discussed. A detailed summary of recently developed enzymatic fuel cell systems, including performance measurements, is conveniently provided in tabular form. The current scientific and engineering challenges involved in developing practical bio-fuel cell systems are described, with particular emphasis on a fundamental understanding of the reaction environment, the performance and stability requirements, modularity and scalability. In a companion review (Part II), new developments in microbial fuel cell technologies are reviewed in the context of fuel sources, electron transfer mechanisms, anode materials and enhanced O(2) reduction.
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Fontes de Energia Bioelétrica/tendências , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Animais , Bactérias/enzimologia , Fungos/enzimologia , Plantas/enzimologiaRESUMO
Recent key developments in microbial fuel cell technology are reviewed. Fuel sources, electron transfer mechanisms, anode materials and enhanced O(2) reduction are discussed in detail. A summary of recently developed microbial fuel cell systems, including performance measurements, is conveniently provided in tabular form. The current challenges involved in developing practical bio-fuel cell systems are described, with particular emphasis on a fundamental understanding of the reaction environment, the performance and stability requirements, modularity and scalability. This review is the second part of a review of bio-fuel cells. In Part 1 a general introduction to bio-fuel cells, including their operating principles and applications, was provided and enzymatic fuel cell technology was reviewed.
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Fontes de Energia Bioelétrica/microbiologia , Bactérias/metabolismo , Reatores Biológicos/microbiologia , Biotecnologia/tendências , Catálise , Transporte de Elétrons , Desenho de Equipamento , Oxirredução , Oxigênio/metabolismoRESUMO
A 30 month prospective study of Acinetobacter species encountered in the Central Pathology Laboratory of St James's Hospital, Dublin, Ireland, was conducted to investigate the prevalence and molecular epidemiology of carbapenem resistance in such isolates. Acinetobacter genomic species 3 (AG3) was found to be the predominant Acinetobacter species (45/114, 39 %) in our institution. A total of 11 % of all Acinetobacter species (12/114) and 22 % of AG3 isolates (10/45) were carbapenem resistant. Carbapenem resistance was mediated by Ambler class D beta-lactamase OXA-23 in all 12 isolates, with insertion sequence ISAba1 found upstream of bla(OXA-23). ISAba1 was also found upstream of bla(ADC-25), which encodes the enzyme AmpC, in an Acinetobacter baumannii isolate, and upstream of the aminoglycoside-acetyltransferase-encoding gene aacC2 in three AG3 isolates. Inter-species plasmidic transfer was most likely involved in the emergence and spread of bla(OXA-23) among the Acinetobacter isolates within our institution. The emergence of carbapenem resistance was associated not only with prior carbapenem use but also with the use of other antimicrobial agents, most notably beta-lactam/beta-lactamase-inhibitor combinations. The study demonstrated the emerging trend of carbapenem resistance in the wider context of the Acinetobacter genus, and reiterated the paramount importance of the prudent use of antimicrobial agents, stringent infection control measures and resistance surveillance of pathogens.
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Infecções por Acinetobacter/epidemiologia , Acinetobacter/classificação , Acinetobacter/efeitos dos fármacos , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Infecção Hospitalar/epidemiologia , Farmacorresistência Bacteriana , Acinetobacter/genética , Acinetobacter/isolamento & purificação , Infecções por Acinetobacter/microbiologia , Adulto , Idoso , Proteínas de Bactérias/genética , Infecção Hospitalar/microbiologia , Elementos de DNA Transponíveis , Feminino , Hospitais Universitários , Humanos , Irlanda/epidemiologia , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Prevalência , beta-Lactamases/genéticaAssuntos
Doenças Musculoesqueléticas/terapia , Fator de Crescimento Transformador beta/antagonistas & inibidores , Receptores de Activinas Tipo II/antagonistas & inibidores , Receptores de Activinas Tipo II/genética , Receptores de Activinas Tipo II/fisiologia , Animais , Anticorpos Monoclonais/uso terapêutico , Folistatina/uso terapêutico , Inibidores de Histona Desacetilases , Homeostase , Humanos , Modelos Biológicos , Músculo Esquelético/fisiopatologia , Doenças Musculoesqueléticas/genética , Doenças Musculoesqueléticas/fisiopatologia , Mutação , Miostatina , Fragmentos de Peptídeos/uso terapêutico , Transdução de Sinais , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/imunologia , Fator de Crescimento Transformador beta/fisiologiaRESUMO
This study determined the types of AmpC enzymes produced by Klebsiella pneumoniae isolates resistant to third-generation cephalosporins and the clonality of these isolates. The presence of AmpC enzymes was identified by cephalosporin-cloxacillin synergy tests. Genes encoding AmpC enzymes were characterised by PCR and sequencing. Pulsed-field gel electrophoresis (PFGE) was used to type the isolates. Fifteen K. pneumoniae isolates were positive for bla(AmpC), 13 were positive for bla(ACC-1) and two were positive for bla(DHA-1). Production of the DHA-1 enzyme was inducible. The ampR gene was identified upstream of the bla(DHA-1) gene. PFGE demonstrated the polyclonal origin of the isolates carrying bla(ACC-1).