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1.
BMC Infect Dis ; 20(1): 810, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33158426

RESUMO

PURPOSE: The purpose of this study was to explore the clinical features, risk factors, and outcomes of mixed Candida albicans/bacterial bloodstream infections (mixed-CA/B-BSIs) compared with monomicrobial Candida albicans bloodstream infection (mono-CA-BSI) in adult patients in China. METHODS: All hospitalized adults with Candida albicans bloodstream infection (CA-BSI) were recruited for this retrospective observational study from January 1, 2013, to December 31, 2018. RESULTS: Of the 117 patients with CA-BSI, 24 patients (20.5%) had mixed-CA/B-BSIs. The most common copathogens were coagulase-negative Staphylococcus (CNS) (24.0%), followed by Klebsiella pneumoniae (20.0%) and Staphylococcus aureus (16.0%). In the multivariable analysis, a prior ICU stay > 2 days (adjusted odds ratio [OR], 7.445; 95% confidence interval [CI], 1.152-48.132) was an independent risk factor for mixed-CA/B-BSIs. Compared with patients with mono-CA-BSI, patients with mixed-CA/B-BSIs had a prolonged length of mechanical ventilation [17.5 (4.5, 34.8) vs. 3.0 (0.0, 24.5), p = 0.019] and prolonged length of ICU stay [22.0 (14.3, 42.2) vs. 8.0 (0.0, 31.5), p = 0.010]; however, mortality was not significantly different. CONCLUSIONS: There was a high rate of mixed-CA/B-BSIs cases among CA-BSI cases, and CNS was the predominant coexisting species. A prior ICU stay > 2 days was an independent risk factor for mixed -CA/B-BSIs. Although there was no difference in mortality, the outcomes of patients with mixed -CA/B-BSIs, including prolonged length of mechanical ventilation and prolonged length of ICU stay, were worse than those with mono-CA-BSI; this deserves further attention from clinicians.


Assuntos
Bacteriemia/complicações , Candida albicans/isolamento & purificação , Candidíase/complicações , Infecções por Klebsiella/complicações , Klebsiella pneumoniae/isolamento & purificação , Infecções Estafilocócicas/complicações , Staphylococcus aureus/isolamento & purificação , Idoso , Bacteriemia/microbiologia , Bacteriemia/mortalidade , Candidíase/microbiologia , Candidíase/mortalidade , China/epidemiologia , Infecção Hospitalar/microbiologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Infecções por Klebsiella/microbiologia , Infecções por Klebsiella/mortalidade , Masculino , Pessoa de Meia-Idade , Respiração Artificial/efeitos adversos , Estudos Retrospectivos , Fatores de Risco , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/mortalidade
2.
BMC Infect Dis ; 20(1): 816, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33167886

RESUMO

BACKGROUND: The prevalence of Staphylococcus aureus varies depending on the healthcare facility, region and country. To understand its genetic diversity, transmission, dissemination, epidemiology and evolution in a particular geographical location, it is important to understand the similarities and variations in the population being studied. This can be achieved by using various molecular characterisation techniques. This study aimed to provide detailed molecular characterisation of South African mecA-positive S. aureus blood culture isolates by describing the SCCmec types, spa types and to lesser extent, the sequence types obtained from two consecutive national surveillance studies. METHODS: S. aureus blood culture isolates from a national laboratory-based and enhanced surveillance programme were identified and antimicrobial susceptibility testing was performed using automated systems. A real-time PCR assay confirmed the presence of the methicillin-resistance determinant, mecA. Conventional PCR assays were used to identify the SCCmec type and spa type, which was subsequently analysed using the Ridom StaphType™ software. Multilocus sequence typing was performed on selected isolates using conventional methods. MRSA clones were defined by their sequence type (ST), SCCmec type and spa type. RESULTS: A detailed description of findings is reported in this manuscript. SCCmec type III predominated overall followed by type IV. A total of 71 different spa types and 24 novel spa types were observed. Spa type t037 was the most common and predominated throughout followed by t1257. Isolates were multidrug resistant; isolates belonging to all SCCmec types were resistant to most of the antibiotics with the exception of type I; isolates with spa type t045 showed resistance to all antibiotics except vancomycin. The most diverse SCCmec-spa type complex was composed of the SCCmec type IV element and 53 different spa types. CONCLUSION: Although ST data was limited, thereby limiting the number of clones that could be identified, the circulating clones were relatively diverse.


Assuntos
Proteínas de Bactérias/genética , Variação Genética , Sequências Repetitivas Dispersas/genética , Staphylococcus aureus Resistente à Meticilina/genética , Proteínas de Ligação às Penicilinas/genética , Infecções Estafilocócicas/epidemiologia , Proteína Estafilocócica A/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Proteínas de Bactérias/sangue , Hemocultura , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/genética , Humanos , Meticilina/farmacologia , Meticilina/uso terapêutico , Resistência a Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Proteínas de Ligação às Penicilinas/sangue , Reação em Cadeia da Polimerase em Tempo Real , África do Sul/epidemiologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Vancomicina/farmacologia , Vancomicina/uso terapêutico
3.
Biomedica ; 40(Supl. 2): 50-67, 2020 10 30.
Artigo em Espanhol | MEDLINE | ID: mdl-33152188

RESUMO

At the end of 2019, in Wuhan, China, the outbreak of a new coronavirus began and quickly spread throughout the world infecting and claiming thousands of lives. To date, certain comorbidities are known to be risk factors for unsatisfactory disease outcomes, but little has been reported regarding hemodialysis patients despite being a population at high risk of infection, complications, and death. Here we describe the clinical course, clinical manifestations and complications of COVID-19 in seven patients on permanent hemodialysis. We also make recommendations for the management of patients with chronic kidney disease.


Assuntos
Betacoronavirus , Infecções por Coronavirus/complicações , Falência Renal Crônica/complicações , Pneumonia Viral/complicações , Diálise Renal , Adulto , Bacteriemia/complicações , Técnicas de Laboratório Clínico , Colômbia/epidemiologia , Terapia Combinada , Infecções por Coronavirus/sangue , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/terapia , Diabetes Mellitus Tipo 2/complicações , Suscetibilidade a Doenças , Feminino , Humanos , Hipertensão/complicações , Falência Renal Crônica/sangue , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/diagnóstico , Pneumonia Viral/terapia , Diálise Renal/métodos , Fatores Socioeconômicos , Infecções Estafilocócicas/complicações
4.
An Acad Bras Cienc ; 92(suppl 2): e20201216, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33084762

RESUMO

Staphylococcus aureus (S. aureus) is a highly versatile Gram-positive bacterium that is carried asymptomatically by up to 30% of healthy people, while being a major cause of healthcare-associated infections, making it a worldwide problem in clinical medicine. The adaptive evolution of S. aureus strains is demonstrated by its remarkable capacity to promptly develop high resistance to multiple antibiotics, thus limiting treatment choice. Nowadays, there is a continuous demand for an alternative to the use of antibiotics for S. aureus infections and a strategy to control the spread or to kill phylogenetically related strains. In this scenario, bacteriocins fit as with a promising and interesting alternative. These molecules are produced by a range of bacteria, defined as ribosomally synthesized peptides with bacteriostatic or bactericidal activity against a wide range of pathogens. This work reviews ascertained the main antibiotic-resistance mechanisms of S. aureus strains and the current, informative content concerning the applicability of the use of bacteriocins overlapping the use of conventional antibiotics in the context of S. aureus infections. Besides, we highlight the possible application of these biomolecules on an industrial scale in future work.


Assuntos
Bacteriocinas , Infecções Estafilocócicas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bactérias Gram-Positivas , Humanos , Testes de Sensibilidade Microbiana , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus
5.
Rev Prat ; 70(6): 653-656, 2020 Jun.
Artigo em Francês | MEDLINE | ID: mdl-33058612

RESUMO

Skin microbiome: role in human health and skin inflammatory diseases. The skin barrier is a major interface between the human host and its environment. It is colonized by more than 1000 different bacterial species which live at the skin surface or within skin appendages but also of by fungi, virus and mites. In adults, the most abundant bacterial genera are Cutibacterium, Corynebacterium and coagulase negative staphylococci. The composition of the skin microbiome mostly varies according to localization, reflecting different physical, chemical and environmental conditions. Despite constant environmental exposure, the skin microbiome of adults is stable over time. Coagulase negative staphylococci play an important role in skin defense by preventing colonization by pathogens such as Staphylococcus aureus and Streptococcus pyogenes, demonstrating mutualistic relationships with the human host. Skin inflammatory diseases are associated with specific dysbiotic features that probably play an important role in their pathophysiology and may be treatment targets in the future.


Assuntos
Microbiota , Dermatopatias , Infecções Estafilocócicas , Adulto , Humanos , Pele , Staphylococcus aureus
6.
BMC Infect Dis ; 20(1): 761, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33066740

RESUMO

BACKGROUND: Device-associated health care-associated infections (DA-HAIs) in intensive care unit (ICU) patients constitute a major therapeutic issue complicating the regular hospitalisation process and having influence on patients' condition, length of hospitalisation, mortality and therapy cost. METHODS: The study involved all patients treated > 48 h at ICU of the Medical University Teaching Hospital (Poland) from 1.01.2015 to 31.12.2017. The study showed the surveillance and prevention of DA-HAIs on International Nosocomial Infection Control Consortium (INICC) Surveillance Online System (ISOS) 3 online platform according to methodology of the INICC multidimensional approach (IMA). RESULTS: During study period 252 HAIs were found in 1353 (549F/804M) patients and 14,700 patient-days of hospitalisation. The crude infections rate and incidence density of DA-HAIs was 18.69% and 17.49 ± 2.56 /1000 patient-days. Incidence density of ventilator-associated pneumonia (VAP), central line-associated bloodstream infection (CLA-BSI) and catheter-associated urinary tract infection (CA-UTI) per 1000 device-days were 12.63 ± 1.49, 1.83 ± 0.65 and 6.5 ± 1.2, respectively. VAP(137) constituted 54.4% of HAIs, whereas CA-UTI(91) 36%, CLA-BSI(24) 9.6%.The most common pathogens in VAP and CA-UTI was multidrug-resistant (MDR) Acinetobacter baumannii (57 and 31%), and methicillin-resistant Staphylococcus epidermidis (MRSE) in CLA-BSI (45%). MDR Gram negative bacteria (GNB) 159 were responsible for 63.09% of HAIs. The length of hospitalisation of patients with a single DA-HAI at ICU was 21(14-33) days, while without infections it was 6.0 (3-11) days; p = 0.0001. The mortality rates in the hospital-acquired infection group and no infection group were 26.1% vs 26.9%; p = 0.838; OR 0.9633;95% CI (0.6733-1.3782). Extra cost of therapy caused by one ICU acquired HAI was US$ 11,475/Euro 10,035. Hand hygiene standards compliance rate was 64.7%, while VAP, CLA-BSI bundles compliance ranges were 96.2-76.8 and 29-100, respectively. CONCLUSIONS: DA-HAIs was diagnosed at nearly 1/5 of patients. They were more frequent than in European Centre Disease Control report (except for CLA-BSI), more frequent than the USA CDC report, yet less frequent than in limited-resource countries (except for CA-UTI). They prolonged the hospitalisation period at ICU and generated substantial additional costs of treatment with no influence on mortality. The Acinetobacter baumannii MDR infections were the most problematic therapeutic issue. DA-HAIs preventive methods compliance rate needs improvement.


Assuntos
Infecções por Acinetobacter/epidemiologia , Acinetobacter baumannii/genética , Infecções Relacionadas a Cateter/epidemiologia , Hospitais Universitários/economia , Controle de Infecções/métodos , Unidades de Terapia Intensiva/economia , Staphylococcus aureus Resistente à Meticilina/genética , Pneumonia Associada à Ventilação Mecânica/epidemiologia , Infecções Estafilocócicas/epidemiologia , Infecções Urinárias/epidemiologia , Infecções por Acinetobacter/economia , Infecções por Acinetobacter/microbiologia , Infecções por Acinetobacter/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções Relacionadas a Cateter/economia , Infecções Relacionadas a Cateter/microbiologia , Infecções Relacionadas a Cateter/prevenção & controle , Farmacorresistência Bacteriana Múltipla , Feminino , Higiene das Mãos/normas , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Pneumonia Associada à Ventilação Mecânica/economia , Pneumonia Associada à Ventilação Mecânica/microbiologia , Pneumonia Associada à Ventilação Mecânica/prevenção & controle , Polônia/epidemiologia , Reação em Cadeia da Polimerase , Estudos Prospectivos , Infecções Estafilocócicas/economia , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/prevenção & controle , Infecções Urinárias/economia , Infecções Urinárias/microbiologia , Infecções Urinárias/prevenção & controle
7.
Nat Commun ; 11(1): 5431, 2020 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-33110079

RESUMO

Physical forces have profound effects on cellular behavior, physiology, and disease. Perhaps the most intruiguing and fascinating example is the formation of catch-bonds that strengthen cellular adhesion under shear stresses. Today mannose-binding by the Escherichia coli FimH adhesin remains one of the rare microbial catch-bond thoroughly characterized at the molecular level. Here we provide a quantitative demonstration of a catch-bond in living Gram-positive pathogens using force-clamp spectroscopy. We show that the dock, lock, and latch interaction between staphylococcal surface protein SpsD and fibrinogen is strong, and exhibits an unusual catch-slip transition. The bond lifetime first grows with force, but ultimately decreases to behave as a slip bond beyond a critical force (~1 nN) that is orders of magnitude higher than for previously investigated complexes. This catch-bond, never reported for a staphylococcal adhesin, provides the pathogen with a mechanism to tightly control its adhesive function during colonization and infection.


Assuntos
Adesinas Bacterianas/química , Infecções Estafilocócicas/microbiologia , Staphylococcus/metabolismo , Adesinas Bacterianas/genética , Adesinas Bacterianas/metabolismo , Aderência Bacteriana , Fibrinogênio/química , Fibrinogênio/metabolismo , Humanos , Ligação Proteica , Análise Espectral , Infecções Estafilocócicas/metabolismo , Staphylococcus/química , Staphylococcus/genética , Staphylococcus/crescimento & desenvolvimento
8.
J Vet Sci ; 21(5): e77, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33016022

RESUMO

BACKGROUND: Staphylococcus aureus is one of the main microorganisms that causes bovine mastitis, and its well-known virulence characteristics and interactions with the environment are used to aid the design of more efficient therapies. OBJECTIVES: To determine whether the virulence traits, such as antibiotic resistance and biofilm-forming and internalization abilities, of S. aureus isolated from bovine mastitis are related to dairy production system types. METHODS: The study was performed in the Mexican states of Guanajuato and Michoacan. Semi-intensive dairy farms (SIDFs) and family dairy farms (FDFs) (454 and 363 cows, respectively) were included. The 194 milk samples from mastitis affected quarters were collected and 92 strains of S. aureus were isolated and identified by biochemical and molecular tests. Antibiotic resistance, biofilm and internalization assays were performed on 30 randomly selected isolated strains to determine virulence traits, and these strains were equally allocated to the 2 dairy production systems. RESULTS: All 30 selected strains displayed a high degree of resistance (50%-91.7%) to the antibiotics tested, but no significant difference was found between SIDF and FDF isolates. S. aureus strains from SIDFs had an average biofilm forming capacity of up to 36% (18.9%-53.1%), while S. aureus strains from FDFs registered an average of up to 53% (31.5%-77.8%) (p > 0.05). Internalization assays revealed a higher frequency of internalization capacity for strains isolated from FDFs (33.3%) than for those isolated from SIDFs (6.7%) (p > 0.05). fnbpA gen was detected in 46.6% of FDF strains and 33.3% of SIDF strains, and this difference was significant (p < 0.05). CONCLUSIONS: Our findings show that the virulence traits of S. aureus isolates analyzed in this study, depend significantly on several factors, such as phenotype, genotype, and environmental conditions, which are significantly related to dairy production system type and daily management practices.


Assuntos
Biofilmes , Indústria de Laticínios/classificação , Farmacorresistência Bacteriana , Mastite Bovina/microbiologia , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/fisiologia , Staphylococcus aureus/patogenicidade , Animais , Biofilmes/crescimento & desenvolvimento , Bovinos , Farmacorresistência Bacteriana/genética , Fazendas , Feminino , Mastite Bovina/epidemiologia , México/epidemiologia , Prevalência , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Virulência
9.
PLoS One ; 15(10): e0232071, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33052925

RESUMO

A PVL-positive, methicillin-susceptible Staphylococcus aureus was cultured from pus from cervical lymphadenitis of a patient of East-African origin. Microarray hybridisation assigned the isolate to clonal complex (CC) 80 but revealed unusual features, including the presence of the ORF-CM14 enterotoxin homologue and of an ACME-III element as well as the absence of etD and edinB. The isolate was subjected to both, Illumina and Nanopore sequencing allowing characterisation of deviating regions within the strain´s genome. Atypical features of this strain were attributable to the presence of two genomic regions that originated from other S. aureus lineages and that comprised, respectively, 3% and 1.4% of the genome. One deviating region extended from walJ to sirB. It comprised ORF-CM14 and the ACME-III element. A homologous but larger fragment was also found in an atypical S. aureus CC1/ST567 strain whose lineage might have served as donor of this genomic region. This region itself is a chimera comprising fragments from CC1 as well as fragments of unknown origin. The other deviating region comprised the region from htsB to ecfA2, i.e., another 3% of the genome. It was very similar to CC1 sequences. Either this suggests an incorporation of CC1 DNA into the study strain, or alternatively a recombination event affecting "canonical" CC80. Thus, the study strain bears witness of several recombination events affecting supposedly core genomic genes. Although the exact mechanism is not yet clear, such chimerism seems to be an additional pathway in the evolution of S. aureus. This could facilitate also a transmission of virulence and resistance factors and therefore offer an additional evolutionary advantage.


Assuntos
Proteínas de Bactérias/genética , Linfadenite/microbiologia , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Infecções Estafilocócicas/diagnóstico , Staphylococcus aureus/crescimento & desenvolvimento , Quimera/genética , Quimera/crescimento & desenvolvimento , Evolução Molecular , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Pessoa de Meia-Idade , Mutagênese Insercional , Recombinação Genética , Análise de Sequência de DNA , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificação , Supuração
10.
Int J Occup Environ Med ; 11(4): 210-212, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33098405

RESUMO

Folliculitis is a common skin disease, usually benign, which causes inflammation and eventual infections of hair follicles. They may have an infectious etiology, mainly due to the bacteria Staphylococcus aureus; it also occurs due to localized irritation, such as in areas of skin friction and for long periods of immersion in water, as in athletes and workers who are continuously exposed to the aquatic environment. Herein, we report on two fishermen, from fluvial and maritime environments, who presented with chronic aseptic folliculitis associated with daily immersion of their lower extremities while exercising the profession and that regressed when there was a decrease in their contact with water.


Assuntos
Foliculite/microbiologia , Foliculite/patologia , Folículo Piloso/microbiologia , Infecções Estafilocócicas/patologia , Staphylococcus aureus/isolamento & purificação , Adulto , Água Doce , Folículo Piloso/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Infecções Estafilocócicas/microbiologia
11.
BMC Infect Dis ; 20(1): 646, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32873235

RESUMO

BACKGROUND: COVID-19 is known as a new viral infection. Viral-bacterial co-infections are one of the biggest medical concerns, resulting in increased mortality rates. To date, few studies have investigated bacterial superinfections in COVID-19 patients. Hence, we designed the current study on COVID-19 patients admitted to ICUs. METHODS: Nineteen patients admitted to our ICUs were enrolled in this study. To detect COVID-19, reverse transcription real-time polymerase chain reaction was performed. Endotracheal aspirate samples were also collected and cultured on different media to support the growth of the bacteria. After incubation, formed colonies on the media were identified using Gram staining and other biochemical tests. Antimicrobial susceptibility testing was carried out based on the CLSI recommendations. RESULTS: Of nineteen COVID-19 patients, 11 (58%) patients were male and 8 (42%) were female, with a mean age of ~ 67 years old. The average ICU length of stay was ~ 15 days and at the end of the study, 18 cases (95%) expired and only was 1 case (5%) discharged. In total, all patients were found positive for bacterial infections, including seventeen Acinetobacter baumannii (90%) and two Staphylococcus aureus (10%) strains. There was no difference in the bacteria species detected in any of the sampling points. Seventeen of 17 strains of Acinetobacter baumannii were resistant to the evaluated antibiotics. No metallo-beta-lactamases -producing Acinetobacter baumannii strain was found. One of the Staphylococcus aureus isolates was detected as methicillin-resistant Staphylococcus aureus and isolated from the patient who died, while another Staphylococcus aureus strain was susceptible to tested drugs and identified as methicillin-sensitive Staphylococcus aureus. CONCLUSIONS: Our findings emphasize the concern of superinfection in COVID-19 patients due to Acinetobacter baumannii and Staphylococcus aureus. Consequently, it is important to pay attention to bacterial co-infections in critical patients positive for COVID-19.


Assuntos
Infecções por Acinetobacter/complicações , Acinetobacter baumannii/isolamento & purificação , Betacoronavirus/fisiologia , Coinfecção/epidemiologia , Infecções por Coronavirus/complicações , Pneumonia Viral/complicações , Infecções Estafilocócicas/complicações , Staphylococcus aureus/isolamento & purificação , Infecções por Acinetobacter/epidemiologia , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Complicações do Diabetes/epidemiologia , Feminino , Cardiopatias/complicações , Humanos , Hipertensão/complicações , Unidades de Terapia Intensiva , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Sistema Respiratório/microbiologia , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos
12.
Nat Commun ; 11(1): 4446, 2020 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-32895387

RESUMO

Owing to the poor penetration depth of light, phototherapy, including photothermal and photodynamic therapies, remains severely ineffective in treating deep tissue infections such as methicillin-resistant Staphylococcus aureus (MRSA)-infected osteomyelitis. Here, we report a microwave-excited antibacterial nanocapturer system for treating deep tissue infections that consists of microwave-responsive Fe3O4/CNT and the chemotherapy agent gentamicin (Gent). This system, Fe3O4/CNT/Gent, is proven to efficiently target and eradicate MRSA-infected rabbit tibia osteomyelitis. Its robust antibacterial effectiveness is attributed to the precise bacteria-capturing ability and magnetic targeting of the nanocapturer, as well as the subsequent synergistic effects of precise microwaveocaloric therapy from Fe3O4/CNT and chemotherapy from the effective release of antibiotics in infection sites. The advanced target-nanocapturer of microwave-excited microwaveocaloric-chemotherapy with effective targeting developed in this study makes a major step forward in microwave therapy for deep tissue infections.


Assuntos
Nanopartículas de Magnetita/uso terapêutico , Micro-Ondas/uso terapêutico , Osteomielite/tratamento farmacológico , Infecções Estafilocócicas/tratamento farmacológico , Animais , Antibacterianos/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Tratamento Farmacológico/métodos , Óxido Ferroso-Férrico/uso terapêutico , Gentamicinas/uso terapêutico , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Nanotubos de Carbono , Osteomielite/microbiologia , Coelhos
13.
Nat Commun ; 11(1): 4465, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901012

RESUMO

Titanium implants have been widely used in bone tissue engineering for decades. However, orthopedic implant-associated infections increase the risk of implant failure and even lead to amputation in severe cases. Although TiO2 has photocatalytic activity to produce reactive oxygen species (ROS), the recombination of generated electrons and holes limits its antibacterial ability. Here, we describe a graphdiyne (GDY) composite TiO2 nanofiber that combats implant infections through enhanced photocatalysis and prolonged antibacterial ability. In addition, GDY-modified TiO2 nanofibers exert superior biocompatibility and osteoinductive abilities for cell adhesion and differentiation, thus contributing to the bone tissue regeneration process in drug-resistant bacteria-induced implant infection.


Assuntos
Antibacterianos/química , Grafite , Nanofibras/química , Próteses e Implantes , Infecções Relacionadas à Prótese/prevenção & controle , Titânio , Células 3T3 , Animais , Materiais Biocompatíveis/química , Regeneração Óssea , Sobrevivência Celular , Modelos Animais de Doenças , Feminino , Teste de Materiais , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Camundongos , Nanocompostos/química , Osteogênese , Processos Fotoquímicos , Infecções Estafilocócicas/prevenção & controle
15.
J Med Microbiol ; 69(10): 1253-1261, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32909934

RESUMO

Introduction. Staphylococcus aureus is a skin and mucous commensal bacterium of warm-blooded animals. In humans, the nose is the main ecological niche of S. aureus, and nasal carriage is a risk factor for developing an endogenous infection. S. aureus nasal colonization is a multifactorial process, involving inter-species interactions among the nasal microbiota.Aims. The objectives of this study were to characterize the microbiota of carriers and non-carriers of S. aureus and to demonstrate the importance of inter-species relationships in the adhesion of S. aureus, a key step in nasal colonization.Methodology. First, we characterized the nasal microbiota from 30 S. aureus carriers and non-carriers by a culturomic approach. We then evaluated the adhesion of S. aureus, first alone and then along with other bacteria of the nasal microbiota. To do that, we used an in vitro model to measure the interactions among bacteria in the presence of epithelial cells.Results. Analysis of the nasal microbiota of the carriers and non-carriers of S. aureus made it possible to observe that each microbiota has specific features in terms of composition. However, this composition differs significantly between carriers and non-carriers mainly through two bacterial groups: coagulase-negative staphylococci and corynebacteria. In a second part, adhesion of S. aureus to epithelial cells showed competition between S. aureus and these bacteria, suggesting a limitation of nasal colonization by S. aureus.Conclusion. These findings demonstrate the existence of a negative correlation between S. aureus and other species which inhibits adhesion and could limit nasal colonization.


Assuntos
Aderência Bacteriana/fisiologia , Mucosa Nasal/metabolismo , Staphylococcus aureus/metabolismo , Adulto , Bactérias , Portador Sadio/microbiologia , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Feminino , Humanos , Masculino , Microbiota , Cavidade Nasal/microbiologia , Mucosa Nasal/microbiologia , Nariz/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/patogenicidade
16.
Wei Sheng Yan Jiu ; 49(4): 608-612, 2020 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-32928356

RESUMO

OBJECTIVE: To understand the contamination status of Staphylococcus aureus in food and processing. METHODS: From July 2017 to January 2018, raw/cooked meat products, aquatic products, soybean products and other foods for sale were collected from five districts and counties of Chengdu, and some processing samples were collected from school cantons, farms and slaughterhouses of Chengdu. Staphylococcus aureus in food and processing in Chengdu was detected by plate method and PCR method, staphylococcus aureus enterotoxin was determined by enzyme-linked fluorescence immunoassay, and Risk Ranger software was used for semi-quantitative Risk assessment. RESULTS: A total of 429 samples were collected from food and processing in Chengdu. 78 strains(18. 2%) of Staphylococcus aureus were detected by plate method, among which 76 strains were identified as Staphylococcus aureus by PCR. The highest detection rate was found in raw meat(34. 1%), and the highest detection rate was found in raw chicken(54. 2%). The detection rate of Staphylococcus aureus in samples from farmers' markets(34. 0%) was higher than that of supermarkets(28. 3%). Eighteen of the 78 strains produced enterotoxin, raw chicken and duck meat from supermarkets(9) and farmers' markets(6), and hand smears by school cafeteria workers(2). According to the risk score, the food safety risks are in descending order from raw meat products(55 points), soybean products(50 points), cooked meat products(43 points) and aquatic products(43 points). CONCLUSION: Raw meat and soybean products are high risk foods contaminated by S. aureus, cooked meat and aquatic products are medium risk foods.


Assuntos
Infecções Estafilocócicas , Staphylococcus aureus , Animais , Enterotoxinas , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Humanos , Carne
17.
PLoS Biol ; 18(9): e3000856, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32941420

RESUMO

Antibiotic combination therapies are important for the efficient treatment of many types of infections, including those caused by antibiotic-resistant pathogens. Combination treatment strategies are typically used under the assumption that synergies are conserved across species and strains, even though recent results show that the combined treatment effect is determined by specific drug-strain interactions that can vary extensively and unpredictably, both between and within bacterial species. To address this problem, we present a new method in which antibiotic synergy is rapidly quantified on a case-by-case basis, allowing for improved combination therapy. The novel CombiANT methodology consists of a 3D-printed agar plate insert that produces defined diffusion landscapes of 3 antibiotics, permitting synergy quantification between all 3 antibiotic pairs with a single test. Automated image analysis yields fractional inhibitory concentration indices (FICis) with high accuracy and precision. A technical validation with 3 major pathogens, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus, showed equivalent performance to checkerboard methodology, with the advantage of strongly reduced assay complexity and costs for CombiANT. A synergy screening of 10 antibiotic combinations for 12 E. coli urinary tract infection (UTI) clinical isolates illustrates the need for refined combination treatment strategies. For example, combinations of trimethoprim (TMP) + nitrofurantoin (NIT) and TMP + mecillinam (MEC) showed synergy, but only for certain individual isolates, whereas MEC + NIT combinations showed antagonistic interactions across all tested strains. These data suggest that the CombiANT methodology could allow personalized clinical synergy testing and large-scale screening. We anticipate that CombiANT will greatly facilitate clinical and basic research of antibiotic synergy.


Assuntos
Antibacterianos/administração & dosagem , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Sinergismo Farmacológico , Testes de Sensibilidade Microbiana/métodos , Algoritmos , Andinocilina/administração & dosagem , Andinocilina/farmacologia , Antibacterianos/farmacologia , Quimioterapia Combinada/métodos , Quimioterapia Combinada/normas , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/microbiologia , Humanos , Testes de Sensibilidade Microbiana/instrumentação , Nitrofurantoína/administração & dosagem , Nitrofurantoína/farmacologia , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/isolamento & purificação , Reprodutibilidade dos Testes , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/isolamento & purificação , Trimetoprima/administração & dosagem , Trimetoprima/farmacologia , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/microbiologia
18.
Cochrane Database Syst Rev ; 9: CD001912, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32997797

RESUMO

BACKGROUND: Staphylococcus aureus causes pulmonary infection in young children with cystic fibrosis. Prophylactic antibiotics are prescribed hoping to prevent such infection and lung damage. Antibiotics have adverse effects and long-term use might lead to infection with Pseudomonas aeruginosa. This is an update of a previously published review. OBJECTIVES: To assess continuous oral antibiotic prophylaxis to prevent the acquisition of Staphylococcus aureus versus no prophylaxis in people with cystic fibrosis, we tested the following hypotheses to investigate whether prophylaxis: 1. improves clinical status, lung function and survival; 2. leads to fewer isolates of Staphylococcus aureus; 3. causes adverse effects (e.g. diarrhoea, skin rash, candidiasis); 4. leads to fewer isolates of other common pathogens from respiratory secretions; 5. leads to the emergence of antibiotic resistance and colonisation of the respiratory tract with Pseudomonas aeruginosa. SEARCH METHODS: We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register, comprising references identified from comprehensive electronic database searches, handsearches of relevant journals and abstract books of conference proceedings. Companies manufacturing anti-staphylococcal antibiotics were contacted. Most recent search of the Group's Register: 27 February 2020. Online trials registries were also searched. Most recent search of online trials registries: 15 September 2020. SELECTION CRITERIA: Randomised trials of continuous oral prophylactic antibiotics (given for at least one year) compared to intermittent antibiotics given 'as required', in people with cystic fibrosis of any disease severity. DATA COLLECTION AND ANALYSIS: The authors assessed studies for eligibility and methodological quality and extracted data. The quality of the evidence was assessed using the GRADE criteria. The review's primary outcomes of interest were lung function by spirometry (forced expiratory volume in one second (FEV1)) and the number of people with one or more isolates of Staphylococcus aureus (sensitive strains). MAIN RESULTS: We included four studies, with a total of 401 randomised participants aged zero to seven years on enrolment; one study is ongoing. The two older included studies generally had a higher risk of bias across all domains, but in particular due to a lack of blinding and incomplete outcome data, than the two more recent studies. We only regarded the most recent study as being generally free of bias, although even here we were not certain of the effect of the per protocol analysis on the study results. Evidence quality was judged to be low for all outcomes assessed after being downgraded based on GRADE assessments. Downgrading decisions were due to limitations in study design (all outcomes), for imprecision and for inconsistency . Prophylactic anti-staphylococcal antibiotics probably make little or no difference to lung function measured as FEV1 % predicted after six years (mean difference (MD) -2.30, 95% confidence interval (CI) -13.59 to 8.99, one study, n = 119, low-quality evidence); but may reduce the number of children having one or more isolates of Staphylococcus aureus at two years (odds ratio (OR) 0.21, 95% CI 0.13 to 0.35, three studies, n = 315, low-quality evidence). At the same time point, there may be little or no effect on nutrition as reported using weight z score (MD 0.06, 95% CI -0.33 to 0.45, two studies, n = 140, low-quality evidence), additional courses of antibiotics (OR 0.18, 95% CI 0.01 to 3.60, one study, n = 119, low-quality evidence) or adverse effects (low-quality evidence). There was no difference in the number of isolates of Pseudomonas aeruginosa between groups at two years (OR 0.74, 95% CI 0.45 to 1.23, three studies, n = 312, low-quality evidence), though there was a trend towards a lower cumulative isolation rate of Pseudomonas aeruginosa in the prophylaxis group at two and three years and towards a higher rate from four to six years. As the studies reviewed lasted six years or less, conclusions cannot be drawn about the long-term effects of prophylaxis. AUTHORS' CONCLUSIONS: Anti-staphylococcal antibiotic prophylaxis may lead to fewer children having isolates of Staphylococcus aureus, when commenced early in infancy and continued up to six years of age. The clinical importance of this finding is uncertain. Further research may establish whether the trend towards more children with CF with Pseudomonas aeruginosa, after four to six years of prophylaxis, is a chance finding and whether choice of antibiotic or duration of treatment might influence this.


Assuntos
Antibioticoprofilaxia , Fibrose Cística/microbiologia , Infecções Respiratórias/prevenção & controle , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus , Viés , Criança , Pré-Escolar , Farmacorresistência Bacteriana , Volume Expiratório Forçado , Crescimento , Humanos , Lactente , Recém-Nascido , Pseudomonas aeruginosa/isolamento & purificação , Ensaios Clínicos Controlados Aleatórios como Assunto , Staphylococcus aureus/isolamento & purificação
19.
Anal Chem ; 92(19): 13396-13404, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32867467

RESUMO

Rapid, accurate, reliable, and risk-free tracking of pathogenic microorganisms at the single-cell level is critical to achieve efficient source control and prevent outbreaks of microbial infectious diseases. For the first time, we report a promising approach for integrating the concepts of a remarkably large Stokes shift and dual-recognition into a single matrix to develop a pathogenic microorganism stimuli-responsive ratiometric fluorescent nanoprobe with speed, cost efficiency, stability, ultrahigh specificity, and sensitivity. As a proof-of-concept, we selected the Gram-positive bacterium Staphylococcus aureus (S. aureus) as the target analyte model, which easily bound to its recognition aptamer and the broad-spectrum glycopeptide antibiotic vancomycin (Van). To improve the specificity and short sample-to-answer time, we employed classic noncovalent π-π stacking interactions as a driving force to trigger the binding of Van and aptamer dual-functionalized near-infrared (NIR) fluorescent Apt-Van-QDs to the surface of an unreported blue fluorescent π-rich electronic carbon nanoparticles (CNPs), achieving S. aureus stimuli-responsive ratiometric nanoprobe Apt-Van-QDs@CNPs. In the assembly of Apt-Van-QDs@CNPs, the blue CNPs (energy donor) and NIR Apt-Van-QDs (energy acceptor) became close to allow the fluorescence resonance energy transfer (FRET) process, leading to a remarkable blue fluorescence quenching for the CNPs at ∼465 nm and a clear NIR fluorescence enhancement for Apt-Van-QDs at ∼725 nm. In the presence of S. aureus, the FRET process from CNPs to Apt-Van-QDs was disrupted, causing the nanoprobe Apt-Van-QDs@CNPs to display a ratiometric fluorescent response to S. aureus, which exhibited a large Stokes shift of ∼260 nm and rapid sample-to-answer detection time (∼30.0 min). As expected, the nanoprobe Apt-Van-QDs@CNPs showed an ultrahigh specificity for ratiometric fluorescence detection of S. aureus with a good detection limit of 1.0 CFU/mL, allowing the assay at single-cell level. Moreover, we also carried out the precise analysis of S. aureus in actual samples with acceptable results. We believe that this work offers new insight into the rational design of efficient ratiometric nanoprobes for rapid on-site accurate screening of pathogenic microorganisms at the single-cell level in the early stages, especially during the worldwide spread of COVID-19 today.


Assuntos
Bactérias/química , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/microbiologia , Técnicas Biossensoriais/métodos , Corantes Fluorescentes/síntese química , Nanotecnologia/métodos , Antibacterianos/farmacologia , Aptâmeros de Nucleotídeos , Infecções por Coronavirus/complicações , Infecções por Coronavirus/microbiologia , Fluorescência , Transferência Ressonante de Energia de Fluorescência , Microbiologia de Alimentos/métodos , Humanos , Nanopartículas , Pandemias , Pneumonia Viral/complicações , Pneumonia Viral/microbiologia , Sensibilidade e Especificidade , Espectroscopia de Luz Próxima ao Infravermelho , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/química , Vancomicina/farmacologia
20.
PLoS One ; 15(9): e0238991, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32946486

RESUMO

BACKGROUND: Invasive Staphylococcus aureus infections are a common cause of morbidity and mortality in children. In the early 2000's the proportion of infections due the methicillin-resistant S. aureus (MRSA) increased rapidly. We described the clinical and molecular epidemiology of invasive S. aureus disease in a pediatric population. METHODS: We prospectively identified children in Utah with invasive S. aureus infections. Medical records were reviewed to determine diagnosis and clinical characteristics. Isolates were genotyped using multi-locus sequence typing. The presence of genes encoding the Panton-Valentine leukocidin (PVL) was determined using polymerase chain reaction. RESULTS: Over a 4-year period between January 2009 and December 2012, we identified 357 children, hospitalized at Primary Children's Hospital, with invasive S. aureus infections and isolates available for the study. Methicillin-susceptible S. aureus (MSSA) caused 79% of disease, while MRSA caused only 21% of disease. Mortality associated with invasive S. aureus infection was 3.6%. The most common diagnoses were osteoarticular infections (38%) followed by central line associated blood stream infections (19%) and pneumonia (12%). We identified 41 multi-locus sequence types. The majority of isolates belonged to 6 predominant clonal complexes (CC5, CC8, CC15, CC30, CC45, CC59). PVL was present in a minority (16%) of isolates, of which most were ST8 MRSA. CONCLUSIONS: MSSA was the primary cause of invasive S. aureus infections at our institution throughout the study period. A limited number of predominant strains accounted for the majority of invasive disease. The classic virulence factor PVL was uncommon in MSSA isolates. Further study is needed to improve our understanding of S. aureus virulence and disease pathogenesis.


Assuntos
Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/genética , Antibacterianos/uso terapêutico , Técnicas de Tipagem Bacteriana/métodos , Criança , Pré-Escolar , Feminino , Genótipo , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Testes de Sensibilidade Microbiana , Epidemiologia Molecular/métodos , Tipagem de Sequências Multilocus/métodos , Infecções Estafilocócicas/genética , Staphylococcus aureus/patogenicidade , Utah/epidemiologia , Fatores de Virulência/genética
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