RESUMO
Staphylococcus aureus and Staphylococcus epidermidis are among the most important bacterial species responsible for biofilm formation on indwelling medical devices, including orthopaedic implants. The increasing resistance to antimicrobials, partly attributed to the ability to form biofilms, is a challenge for the development of new antimicrobial agents. In this study, the cell-free supernatant obtained from sponge-associated Enterobacter strain 84.3 culture inhibited biofilm formation (>65%) and dissociated mature biofilm (>85%) formed by S. aureus and S. epidermidis strains. The culture supernatant was subjected to solvent partitioning and the aqueous extract presented a concentration-dependent antibiofilm activity for each strain with a minimum biofilm eradication concentration (MBEC) ranging from 16 to 256 µg/mL. The effect of the aqueous extract on mature S. aureus biofilm was analyzed by confocal scanning laser microscopy, showing a significant reduction of the biofilm layer as well as diminished interactions among the cells. This extract is not toxic for mammalian cells (L929 cell line). Studies targeting substances with antibiofilm activity gained significant attention in recent years due to difficult-to-treat biofilm infections. Here, sponge-associated Enterobacter 84.3 proved to be a source of substances capable of eradicating staphylococcal biofilm, with potential medical use in the future.
Assuntos
Antibacterianos/farmacologia , Biofilmes/crescimento & desenvolvimento , Extratos Celulares/farmacologia , Enterobacter/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos , Animais , Infecções Relacionadas a Cateter/tratamento farmacológico , Infecções Relacionadas a Cateter/microbiologia , Cateteres de Demora/microbiologia , Linhagem Celular , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/microbiologia , Células L , Camundongos , Testes de Sensibilidade Microbiana , Poríferos/microbiologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/prevenção & controleRESUMO
BACKGROUND: Staphylococcus aureus is a human pathogen of clinical importance related to a variety of infections. AIM: The objective of this study was to analyze the molecular and epidemiological characteristics of S. aureus obtained from healthcare professionals (HCP) of a hospital in southwestern Bahia, Brazil. METHODS: Samples were collected from hands, nasal cavity, and laboratory coats of 80 HCP. The bacterial isolates recovered from 240 samples were identified as S. aureus, and then analyzed for their antimicrobial resistance profile, genotypic characterization, and pathogenicity. FINDINGS: 178 isolates were identified as S. aureus, being mostly isolated from the nasal cavity. Thirty isolates (16.8%) were characterized as MRSA. The virulence gene frequency varied according to isolate source. All virulence genes were identified in at least one hand isolate. Isolates from laboratory coats did not show seb and pvl. Isolates from the nasal cavity did not exhibit pvl. The SCCmec type I was identified in 56.7% of MRSA isolates. Among MRSA isolates, 14 PFGE pulsotypes were characterized, with profile A being predominant (nine isolates). Clonal complexes CC5, CC45, and CC398 were found. MRSA isolates induced cytokine gene expression in macrophages, with IL-10 and IL-17 being expressed more often. CONCLUSION: We found a high colonization rate for S. aureus among HCP. Moreover, we observed that MRSA strains presented different virulence factors and could induce cytokine gene expression, indicating an urgent need to control colonization rates of HCP by MRSA isolates in order to protect hospital patients and the general public.
RESUMO
BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) colonization in Atopic Dermatitis (AD) patients can contribute to worsening their clinical condition. OBJECTIVE: A cohort study was carried out to determine the incidence of MRSA acquisition and its risk factors in AD children. METHODS: Patients with AD (2 months-14 years old) were followed up for about 1 year at a reference center for AD treatment in Rio de Janeiro, Brazil, from September 2011 to February 2014. Nasal swabs from patients and contacts were collected every 2 months. The SCORAD system assessed the severity of the AD. S. aureus isolates were evaluated to determine the methicillin resistance and the clonal lineages. RESULTS: Among 117 AD patients, 97 (82.9%) were already colonized with S. aureus and 26 (22.2%) had MRSA at the first evaluation. The incidence of MRSA acquisition in the cohort study was 27.47% (n = 25). The SCORAD assessments were: mild (46.15%), moderate (37.36%) or severe (16.48%). Risk factors were: colonized MRSA contacts (HR = 2.27; 95% CI: 1.16-7.54), use of cyclosporine (HR = 5.84; 95% CI: 1.70-19.98), moderate or severe AD (HR = 3.26; 95% CI: 1.13-9.37). Protective factors were: availability of running water (HR = 0.21; 95% CI: 0.049-0.96) and use of antihistamines (HR = 0.21; 95% IC: 0.64-0.75). MRSA isolates carried the SCCmec type IV and most of them were typed as USA800/ST5. CONCLUSIONS: The high incidence of MRSA acquisition found among AD patients and the risk factors associated show that an effective surveillance of MRSA colonization in these patients is needed.
Assuntos
Dermatite Atópica/epidemiologia , Dermatite Atópica/microbiologia , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Adolescente , Antibacterianos/farmacologia , Brasil/epidemiologia , Criança , Pré-Escolar , Estudos de Coortes , Ciclosporina , Feminino , Antagonistas dos Receptores Histamínicos , Humanos , Incidência , Lactente , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Análise Multivariada , Estudos Prospectivos , Fatores de Proteção , Fatores de RiscoRESUMO
This study characterized 30 MRSA isolates from intensive care unit (ICU) environment and equipment surfaces and healthy children. The SCCmec types I, IVa and V were detected in HA-MRSA isolates while CA-MRSA showed the SCCmec type IVa and V. Most isolates were classified as agr group II. All isolates presented the sei gene, and only HA-MRSA were positive for etb e tst genes. Three genotypes were related to Pediatric (ST5/SCCmecIV) and Berlin (ST45/SCCmecIV) clones. The present study showed molecular similarity between CA- and HA-MRSA isolates in hospital and community settings in a Brazilian region.
Assuntos
Infecções Comunitárias Adquiridas/microbiologia , Infecção Hospitalar/microbiologia , Unidades de Terapia Intensiva/estatística & dados numéricos , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Brasil , Equipamentos e Provisões Hospitalares/microbiologia , Genótipo , Humanos , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Infecções Estafilocócicas/genética , Infecções Estafilocócicas/microbiologia , Fatores de Virulência/genética , Fatores de Virulência/isolamento & purificaçãoRESUMO
ABSTRACT This study characterized 30 MRSA isolates from intensive care unit (ICU) environment and equipment surfaces and healthy children. The SCCmec types I, IVa and V were detected in HA-MRSA isolates while CA-MRSA showed the SCCmec type IVa and V. Most isolates were classified as agr group II. All isolates presented the sei gene, and only HA-MRSA were positive for etb e tst genes. Three genotypes were related to Pediatric (ST5/SCCmecIV) and Berlin (ST45/SCCmecIV) clones. The present study showed molecular similarity between CA- and HA-MRSA isolates in hospital and community settings in a Brazilian region.
Assuntos
Humanos , Infecção Hospitalar/microbiologia , Infecções Comunitárias Adquiridas/microbiologia , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/genética , Unidades de Terapia Intensiva/estatística & dados numéricos , Infecções Estafilocócicas/genética , Infecções Estafilocócicas/microbiologia , Brasil , Fatores de Virulência/isolamento & purificação , Fatores de Virulência/genética , Equipamentos e Provisões Hospitalares/microbiologia , Staphylococcus aureus Resistente à Meticilina/patogenicidade , GenótipoRESUMO
BACKGROUND: Pseudomonas aeruginosa is an important human pathogen that causes severe infections in a wide range of immunosuppressed patients. Herein, we evaluated the proteolytic profiles of 96 Brazilian clinical isolates of P. aeruginosa recovered from diverse anatomical sites. METHODS: Cell-associated and extracellular proteases were evidenced by gelatin-SDS-PAGE and by the cleavage of soluble gelatin. Elastase was measured by using the peptide substrate N-succinyl-Ala-Ala-Ala-p-nitroanilide. The prevalence of elastase genes (lasA and lasB) was evaluated by PCR. RESULTS: Bacterial extracts were initially applied on gelatin-SDS-PAGE and the results revealed four distinct zymographic profiles as follows: profile I (composed by bands of 145, 118 and 50kDa), profile II (118 and 50kDa), profile III (145kDa) and profile IV (118kDa). All the proteolytic enzymes were inhibited by EDTA, identifying them as metalloproteases. The profile I was the most detected in both cellular (79.2%) and extracellular (84.4%) extracts. Overall, gelatinase and elastase activities measured in the spent culture media were significantly higher (around 2-fold) compared to the cellular extracts and the production level varied according to the site of bacterial isolation. For instance, tracheal secretion isolates produced elevated amount of gelatinase and elastase measured in both cellular and extracellular extracts. The prevalence of elastase genes revealed that 100% isolates were lasB-positive and 85.42% lasA-positive. Some positive/negative correlations were showed concerning the production of gelatinase, elastase, isolation site and antimicrobial susceptibility. CONCLUSION: The protease production was highly heterogeneous in Brazilian clinical isolates of P. aeruginosa, which corroborates the genomic/metabolic versatility of this pathogen.
Assuntos
Proteínas de Bactérias/análise , Metaloproteases/análise , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/enzimologia , Proteínas de Bactérias/genética , Líquidos Corporais/microbiologia , Brasil , Fibrose Cística/complicações , Ácido Edético/farmacologia , Eletroforese em Gel de Poliacrilamida , Gelatinases/antagonistas & inibidores , Gelatinases/genética , Gelatinases/isolamento & purificação , Genes Bacterianos , Humanos , Metaloproteases/antagonistas & inibidores , Metaloproteases/genética , Especificidade de Órgãos , Elastase Pancreática/antagonistas & inibidores , Elastase Pancreática/genética , Elastase Pancreática/isolamento & purificação , Pneumonia Bacteriana/microbiologia , Inibidores de Proteases/farmacologia , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/isolamento & purificação , Reto/microbiologia , Sistema Respiratório/microbiologia , Virulência , Infecção dos Ferimentos/microbiologiaRESUMO
OBJECTIVES: The beneficial antimicrobial properties of 1,10-phenanthroline (phen)-based drugs, together with the imperative need to develop new chemotherapeutic options for prevention/treatment of infections caused by MDR Gram-negative bacteria, led us to evaluate the effects of phen, 1,10-phenanthroline-5,6-dione (phendione), [Ag(phendione)2]ClO4 and [Cu(phendione)3](ClO4)2·4H2O on planktonic- and biofilm-growing Pseudomonas aeruginosa. METHODS: Thirty-two non-duplicated Brazilian clinical isolates of P. aeruginosa with distinct genetic backgrounds were used in all experiments. The effect of test compounds on planktonic bacterial proliferation was determined as recommended by CLSI protocol. The effect on biofilm formation was evaluated by crystal violet incorporation (biomass determination) and XTT (viability assay). Mature biofilm disorganization was evidenced by staining with crystal violet. RESULTS: Phen-based compounds presented anti-P. aeruginosa activity, but with different potencies concerning the geometric mean MIC: [Cu(phendione)3](2+) (7.76 µM)â>â[Ag(phendione)2](+) (14.05 µM)â>âphendione (31.15 µM)â>âphen (579.28 µM). MICs of each compound were similar irrespective of whether the P. aeruginosa isolates were susceptible or resistant to classical antimicrobials (ceftazidime, meropenem and imipenem). The pretreatment of bacteria with phen, phendione and phendione's metal derivatives at 0.5â×âMIC value inhibited biofilm formation, particularly the use of [Cu(phendione)3](2+) and [Ag(phendione)2](+), which significantly reduced both biomass (48% and 44%, respectively) and viability (78% and 77%, respectively). The compounds studied also disrupted mature biofilm in a dose-dependent manner, especially [Ag(phendione)2](+) and [Cu(phendione)3](2+) (IC50, 9.39 and 10.16 µM, respectively). CONCLUSIONS: Coordination of phendione to Ag(+) and Cu(2+) represents a new promising group of anti-infective agents, which revealed a potent anti-P. aeruginosa action against both planktonic- and biofilm-growing cells.
Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Cobre/farmacologia , Fenantrolinas/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Prata/farmacologia , Brasil , Humanos , Testes de Sensibilidade Microbiana , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/isolamento & purificação , Pseudomonas aeruginosa/fisiologiaRESUMO
AIMS: This cross-sectional study investigated the association between eight herpesviruses and the bacterial community profiles from the oral cavity of children with and without leukaemia. METHODS: Sixty participants (aged 3-13), divided into the leukaemia group (LG) and healthy group (HG), were evaluated. Collection of medical data, intraoral examination and collection of clinical specimens were carried out. Single PCR and nested-PCR techniques were used to identify the viral types; denaturing gradient gel electrophoresis (DGGE) and real-time PCR techniques were used to evaluate the profile and abundance of bacterial communities. RESULTS: All the children with leukaemia were positive for at least one type of herpesvirus, compared with healthy participants (33.3%; p<0.000). Human cytomegalovirus (HCMV; 46.7%), human herpesvirus-7 (HHV-7; 20%) and HHV-8 (77.3%) were in higher prevalence in the LG (p ≤ 0.01). Children with leukaemia had positive associations with the presence of HCMV, HHV-7 and HHV-8 in the oral cavity when under chemotherapy (p<0.05). There was a qualitative (means of DGGE bands) and quantitative (means of 16S rRNA gene abundance) difference in relation to the bacterial community between the two groups (p<0.05). CONCLUSIONS: Based on the results, the prevalence of herpesviruses and the qualitative bacterial profiles was higher in children with leukaemia and HCMV, HHV-7 and HHV-8 were related to the use of chemotherapy. Moreover, HHV-6 was correlated with an increased bacterial community profile in patients with leukaemia (p<0.05). More attention should be paid to the oral health of these individuals, mainly those under chemotherapy, in order to prevent infections by opportunistic pathogens.
Assuntos
Antineoplásicos/uso terapêutico , Bactérias/efeitos dos fármacos , Infecções por Herpesviridae/virologia , Herpesviridae/efeitos dos fármacos , Leucemia/tratamento farmacológico , Boca/efeitos dos fármacos , Saúde Bucal , Adolescente , Antineoplásicos/efeitos adversos , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Estudos de Casos e Controles , Criança , Pré-Escolar , Estudos Transversais , DNA Bacteriano/isolamento & purificação , DNA Viral/isolamento & purificação , Eletroforese em Gel de Gradiente Desnaturante , Feminino , Herpesviridae/classificação , Herpesviridae/genética , Herpesviridae/isolamento & purificação , Infecções por Herpesviridae/diagnóstico , Humanos , Leucemia/diagnóstico , Masculino , Boca/microbiologia , Boca/virologia , Reação em Cadeia da Polimerase em Tempo RealRESUMO
Pseudomonas aeruginosa is an opportunistic human pathogen responsible for causing a huge variety of acute and chronic infections with significant levels of morbidity and mortality. Its success as a pathogen comes from its genetic/metabolic plasticity, intrinsic/acquired antimicrobial resistance, capacity to form biofilm and expression of numerous virulence factors. Herein, we have analyzed the genetic variability, antimicrobial susceptibility as well as the production of metallo-ß-lactamases (MBLs) and virulence attributes (elastase, pyocyanin and biofilm) in 96 strains of P. aeruginosa isolated from different anatomical sites of patients attended at Brazilian hospitals. Our results revealed a great genetic variability, in which 86 distinct RAPD types (89.6% of polymorphisms) were detected. Regarding the susceptibility profile, 48 strains (50%) were resistant to the antimicrobials, as follows: 22.92% to the three tested antibiotics, 12.5% to both imipenem and meropenem, 11.46% to ceftazidime only, 2.08% to imipenem only and 1.04% to both ceftazidime and meropenem. Out of the 34 clinical strains of P. aeruginosa resistant to both imipenem and meropenem, 25 (73.53%) were MBL producers by phenotypic method while 12 (35.29%) were PCR positive for the MBL gene SPM-1. All P. aeruginosa strains produced pyocyanin, elastase and biofilm, although in different levels. Some associations were demonstrated among the susceptibility and/or production of these virulence traits with the anatomical site of strain isolation. For instance, almost all strains isolated from urine (85.71%) were resistant to the three antibiotics, while the vast majority of strains isolated from rectum (95%) and mouth (66.67%) were susceptible to all tested antibiotics. Urine isolates produced the highest pyocyanin concentration (20.15±5.65 µg/ml), while strains isolated from pleural secretion and mouth produced elevated elastase activity (1441.43±303.08 FAU) and biofilm formation (OD590 0.676±0.32), respectively. Also, MBL-positive strains produced robust biofilm compared to MBL-negative strains. Collectively, the production of site-dependent virulence factors can be highlighted as potential therapeutic targets for the treatment of infections caused by heterogeneous and resistant strains of P. aeruginosa.
Assuntos
Variação Genética , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/isolamento & purificação , Fatores de Virulência/genética , Antibacterianos/farmacologia , Biofilmes/crescimento & desenvolvimento , Líquidos Corporais/microbiologia , Brasil , Farmacorresistência Bacteriana , Genótipo , Humanos , Testes de Sensibilidade Microbiana , Tipagem Molecular , Pseudomonas aeruginosa/classificação , Pseudomonas aeruginosa/fisiologia , Técnica de Amplificação ao Acaso de DNA Polimórfico , Virulência , beta-Lactamases/metabolismoRESUMO
This work characterizes MLS(b) resistance in 39 methicillin-resistant Staphylococcus aureus (MRSA) and 32 Staphylococcus epidermidis (MRSE) isolates. Of 21 erm(A) gene encoding MRSA isolates, 71.4% carried SCCmecIII, whereas of 12 isolates carrying the erm(C) gene, 83.3% carried SCCmecIV. Among the 25 MRSE isolates positive for the erm(C) gene, 80% had SCCmecIV or nontypeable cassettes. Isolates carrying these genes had MIC(90) ≥ 256 µg/mL to erythromycin and clindamycin. The msr(A) gene was associated with a low MIC(90) to these drugs. The erm(A) gene was associated with SCCmecIII in MRSA isolates, whereas the erm(C) gene was associated with SCCmecIV in both MRSA and MRSE isolates.
Assuntos
Clindamicina/farmacologia , Farmacorresistência Bacteriana Múltipla , Eritromicina/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos , Estreptogramina B/farmacologia , Proteínas de Bactérias/genética , Brasil/epidemiologia , Cromossomos Bacterianos/genética , Genes Bacterianos , Humanos , Recém-Nascido , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Metiltransferases/genética , Testes de Sensibilidade Microbiana , Proteínas de Ligação às Penicilinas , Fenótipo , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus epidermidis/genética , Staphylococcus epidermidis/isolamento & purificaçãoRESUMO
Staphylococcus aureus encoding Panton-Valentine leukocidin (PVL) genes has become the cause of life-threatening infections. We describe a case of carotid cavernous fistula after bacteremia in a 12-year-old male, caused by a methicillin-susceptible S. aureus isolate carrying the pvl, fnbA, and ebpS genes and related to sequence type 25 (ST25). The patient's condition was complicated by pleural empyema and osteomyelitis in the right femur. The patient was discharged in good clinical condition after 160 days of hospitalization.
Assuntos
Toxinas Bacterianas/genética , Fístula Carótido-Cavernosa/diagnóstico , Infecções Comunitárias Adquiridas/microbiologia , Exotoxinas/genética , Leucocidinas/genética , Sepse/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/isolamento & purificação , Angiografia , Antibacterianos/farmacologia , Fístula Carótido-Cavernosa/complicações , Fístula Carótido-Cavernosa/microbiologia , Fístula Carótido-Cavernosa/patologia , Criança , Infecções Comunitárias Adquiridas/complicações , Empiema/diagnóstico , Empiema/microbiologia , Genótipo , Humanos , Masculino , Meticilina/farmacologia , Tipagem Molecular , Osteomielite/diagnóstico , Osteomielite/epidemiologia , Sepse/complicações , Staphylococcus aureus/classificação , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética , Fatores de Virulência/genéticaRESUMO
Staphylococcus lugdunensis is an unusually virulent coagulase-negative species, which causes serious infection similar to S. aureus. We evaluated the expression of virulence factors such as S. lugdunensis synergistic haemolysin (SLUSH), fibrinogen-binding protein (Fbl), biofilm production and biofilm-production-related genes in 23 S. lugdunensis clinical isolates and one type strain that had been previously characterized for their genotypes. In addition, the biofilm composition and the ability of isolates to adhere to and invade human epithelial lung cells were also investigated. The PCR method used detected the presence of slush and intercellular adhesin (ica) virulence genes in all isolates. All isolates produced the Fbl protein and, with the exception of the type strain, all isolates produced the SLUSH haemolysin. Fourteen (60.9â%) isolates produced biofilms. The detachment assay, using sodium metaperiodate or proteolytic enzymes to analyse the biofilm composition, showed protein-mediated biofilms in two representative isolates, one for each colony type (rough and smooth). All strongly biofilm-producing isolates, including three with rough colony morphology, had the same prevalent PFGE pattern. However, among the representative strains tested, only the S. lugdunensis isolate that formed rough colonies was able to adhere to and invade A549 cell monolayers in the same quantities as those observed with S. aureus isolates (Pâ=â1.000). No significant adhesion or invasion was observed for the other isolates in comparison with the S. aureus isolate, independent of biofilm production or clonality. Our results could explain the incredible ability of this pathogen to cause infections that are as aggressive as S. aureus. In addition, the ability of S. lugdunensis to adhere to and invade eukaryotic cells was also noticed for isolates with rough colony morphology, reinforcing the increased virulence in this species.
Assuntos
Aderência Bacteriana/fisiologia , Células Epiteliais/microbiologia , Mucosa Respiratória/citologia , Staphylococcus lugdunensis/citologia , Staphylococcus lugdunensis/genética , Aderência Bacteriana/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biofilmes , Brasil/epidemiologia , Linhagem Celular Tumoral , Regulação Bacteriana da Expressão Gênica/fisiologia , Humanos , Pulmão/citologia , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus lugdunensis/fisiologiaRESUMO
Staphylococcus epidermidis is the most prevalent coagulase-negative Staphylococcus (CNS) and is a major cause of hospital bacteremia. Based on 18 reference strains and 149 Staphylococcus clinical strains, used in a novel multiplex PCR method, the aim of this study was to identify S. epidermidis with respect to the sequence of three genes: recN, which encodes a recombination/repair protein, mecA (methicillin resistance), and icaAB, which is involved in biofilm formation. Amplicons of 219 bp (S. epidermidis-recN gene), 154 bp (mecA gene), and 546 bp (icaAB genes) were obtained. Reliable results were achieved for 100% of the evaluated strains, suggesting that this new multiplex-PCR approach could be useful for the accurate identification of methicillin-resistant S. epidermidis with the potential to produce biofilm.
Assuntos
Técnicas Bacteriológicas/métodos , Biofilmes/crescimento & desenvolvimento , Resistência a Meticilina , Reação em Cadeia da Polimerase Multiplex/métodos , Infecções Estafilocócicas/microbiologia , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus epidermidis/fisiologia , Amidoidrolases/genética , Proteínas de Bactérias/genética , Enzimas de Restrição do DNA/genética , Humanos , Staphylococcus epidermidis/genética , Staphylococcus epidermidis/isolamento & purificaçãoRESUMO
OBJECTIVE: Herpesvirus infection can cause immunosuppression and then act as a modifier of apical periodontitis, influencing the disease severity and response to treatment. The purpose of this study was to investigate if herpesvirus infection, as inferred by salivary carriage, may influence the endodontic treatment outcome. STUDY DESIGN: The study population included 72 patients who had root canals treated more than 1 year previously because of necrotic pulps and apical periodontitis. At the follow-up examination, 27 of these patients presented with posttreatment apical periodontitis (failure) and 45 individuals exhibited healed/healing periradicular tissues (success). Saliva was collected from these individuals, DNA was extracted, subjected to multiple displacement amplification, and screened by polymerase chain reaction (PCR) assays for the presence of 6 herpesviruses: herpes simplex virus types 1 and 2 (HSV-1/2), Epstein-Barr virus (EBV), human cytomegalovirus (HCMV), human herpesvirus-6 (HHV-6), and human herpesvirus-8 (HHV-8). RESULTS: Except for HSV-1/2, all other herpesviruses were detected in saliva from both healed/healing and diseased groups. HHV-8 was the most frequent herpesvirus found in saliva (84% in success, 89% in failure), followed by HCMV (22% in success, 30% in failure), EBV (16% in success, 18.5% in failure) and HHV-6 (7% in success, 15% in failure). No significant association of herpesvirus carriage in saliva with poor treatment outcome was discernible in the population studied (P > .05). CONCLUSIONS: Data from the present study suggest that herpesvirus infection may not influence the outcome of endodontic treatment. Further longitudinal studies are warranted to confirm these findings.
Assuntos
Falha de Restauração Dentária , Herpesviridae/isolamento & purificação , Periodontite Periapical/terapia , Tratamento do Canal Radicular , Saliva/virologia , Adulto , Distribuição de Qui-Quadrado , DNA Viral/isolamento & purificação , Feminino , Seguimentos , Herpesviridae/genética , Herpesviridae/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Periodontite Periapical/imunologia , Periodontite Periapical/virologia , Estatística como Assunto , Estatísticas não Paramétricas , Resultado do TratamentoRESUMO
OBJECTIVE: Viral-bacterial and bacterial synergism have been suggested to contribute to the pathogenesis of several human diseases. This study sought to investigate the possible associations between 9 candidate endodontic bacterial pathogens and 9 human viruses in samples from acute apical abscesses. STUDY DESIGN: DNA extracts from purulent exudate aspirates of 33 cases of acute apical abscess were surveyed for the presence of 9 selected bacterial species using a 16S ribosomal RNA gene-based nested polymerase chain reaction (PCR) approach. Single or nested PCR assays were used for detection of the human papillomavirus (HPV) and herpesviruses types 1 to 8. RESULTS: Two-thirds of the abscess samples were positive for at least one of the target viruses. Specifically, the most frequently detected viruses were HHV-8 (54.5%); HPV (9%); and varicella zoster virus (VZV), Epstein-Barr virus (EBV), and HHV-6 (6%). Bacterial DNA was present in all cases and the most prevalent bacterial species were Treponema denticola (70%), Tannerella forsythia (67%), Porphyromonas endodontalis (67%), Dialister invisus (61%), and Dialister pneumosintes (57.5%). HHV-8 was positively associated with 7 of the target bacterial species and HPV with 4, but all these associations were weak. Several bacterial pairs showed a moderate positive association. Viral coinfection was found in 6 abscess cases, but no significant viral association could be determined. CONCLUSIONS: Findings demonstrated that bacterial and viral DNA occurred concomitantly in two-thirds of the samples from endodontic abscesses. Although this may suggest a role for viruses in the etiology of apical abscesses, the possibility also exists that the presence of viruses in abscess samples is merely a consequence of the bacterially induced disease process. Further studies are necessary to clarify the role of these viral-bacterial interactions, if any, in the pathogenesis of acute apical abscesses.
Assuntos
Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Herpesviridae/virologia , Abscesso Periapical/microbiologia , Adolescente , Adulto , Infecções por Bacteroidaceae/microbiologia , Infecções por Bacteroides/microbiologia , DNA Bacteriano/análise , DNA Viral/análise , Infecções por Vírus Epstein-Barr/virologia , Bacilos Gram-Negativos Anaeróbios Retos, Helicoidais e Curvos/classificação , Herpes Zoster/virologia , Herpesviridae/classificação , Herpesvirus Humano 6/isolamento & purificação , Herpesvirus Humano 8/isolamento & purificação , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/virologia , Abscesso Periapical/virologia , Reação em Cadeia da Polimerase , Porphyromonas gingivalis/isolamento & purificação , RNA Bacteriano/análise , RNA Ribossômico 16S/análise , Infecções por Roseolovirus/virologia , Treponema denticola/isolamento & purificação , Infecções por Treponema/microbiologia , Adulto JovemRESUMO
In order to validate the Bumelia sartorum Mart., Sapotaceae, traditional use for infection diseases, this study evaluates the antibacterial activity of the stem bark fractions against methicillin-sensitive (MSSA) and methicillin-resistant (MRSA) Staphylococcus aureus strains by using the agar dilution method and reported as MIC (minimal inhibitory concentration). In addition, the DPPH scavenging activity of these fractions was measured and the chemical composition and acute toxicity of the active fraction were also determined. The ethyl acetate (EtOAc) extract was chemically analyzed by LC/MS, direct ionization APCI/MS, ¹H NMR and 13C-NMR. All fractions, except butanol extract, presented high antioxidant activity, especially the methanol and the EtOAc extracts, which showed EC50 values (5.67 and 5.30 µg/mL, respectively) considerably lower than the Gingko-standard EGb 761® (38.58 µg/mL). The antibacterial activity against S. aureus strains was observed in EtOAc (MIC 256-512 µg/mL), which showed a very low toxicity. The chemical study of this fraction revealed the abundant presence of polyphenolic compounds. The antibacterial and antioxidant activities reported in this paper for EtOAc extract from B. sartorum and the low toxicity of this fraction opens the possibility that it could be helpful for the developing of new antibacterial agents for treating S. aureus infections.
RESUMO
INTRODUCTION: It has been suggested that viruses, especially herpesviruses, can play a role in the pathogenesis of marginal and apical periodontitis. This study aimed to detect herpesviruses types 1 to 8, namely herpes simplex virus (HSV-1/2), varicella zoster virus (VZV), Epstein-Barr virus (EBV), human cytomegalovirus (HCMV), human herpesvirus-6 (HHV-6), human herpesvirus-7 (HHV-7), and human herpesvirus-8 (HHV-8) as well as human papillomavirus (HPV) in acute apical abscesses. METHODS: Twenty-four samples were taken by aspiration of the purulent exudate from acute apical abscesses. DNA extracted from clinical samples served as a template in single or nested polymerase chain reaction (PCR) assays for the detection of the target viruses. RESULTS: Control PCR reactions with ß-globin gene primers revealed that all samples but one had detectable human DNA. Of the 23 abscess samples positive for the ß-globin gene, 14 (61%) were positive for at least one of the target human viruses. Thirteen (56.5%) cases had herpesvirus: HHV-8 occurred in 11 (48%), VZV and HHV-6B in two (9%), and HHV-7 and HSV-1/2 in one (4%). EBV and HCMV were not present in any of the examined samples. HPV was detected in three (13%) abscess samples. Viral coinfection was found in five cases, with one case harboring three of the targeted viruses. CONCLUSION: A large number of abscess samples were positive for at least one target virus. Unexpectedly, HHV-8 was for the first time detected and in a high prevalence. Papillomavirus and other herpesviruses were also found for the first time in endodontic abscesses. Although these findings suggest an association, the specific role of viruses in the pathogenesis of acute apical abscesses awaits further clarification.
Assuntos
Infecções por Herpesviridae/complicações , Herpesviridae/isolamento & purificação , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/complicações , Abscesso Periapical/virologia , Doença Aguda , DNA Viral/análise , Herpesviridae/classificação , Herpesviridae/genética , Infecções por Herpesviridae/virologia , Humanos , Papillomaviridae/genética , Pulpite/virologiaRESUMO
Bacterial occurrence in treated root canals, even in patients without post-treatment apical periodontitis, raises the possibility that factors other than mere bacterial presence can be determinants for a favourable outcome of endodontic treatment. Because these factors may be related to the bacterial communities colonizing the root canal, including virulence, density and interactions, the objective of this study was to compare the community structures found in root-canal-treated teeth with (12 samples) and without (11 samples) apical periodontitis lesions by means of a PCR-denaturing gradient gel electrophoresis fingerprinting approach. Results confirmed a polymicrobial composition even in treated patients without post-treatment disease. A large microbial community diversity was observed for treated teeth both with or without disease, but no specific pattern was detected for diseased teeth. Nevertheless, the number of bands from samples with apical periodontitis lesions was statistically significantly higher (P=0.04) than that from samples collected from root-canal-treated teeth without post-treatment apical periodontitis. Furthermore, predominant bands in samples from patients with apical disease were also observed.
Assuntos
Bactérias/classificação , Bactérias/isolamento & purificação , Biodiversidade , Cavidade Pulpar/microbiologia , Periodontite Periapical/microbiologia , Adulto , Idoso , Bactérias/genética , Análise por Conglomerados , Impressões Digitais de DNA , DNA Bacteriano/genética , DNA Ribossômico/genética , Eletroforese em Gel de Poliacrilamida , Humanos , Pessoa de Meia-Idade , Desnaturação de Ácido Nucleico , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genéticaRESUMO
In this study, we standardized and evaluated a multiplex-PCR methodology using specific primers to identify Staphylococcus aureus, Staphylococcus epidermidis and Staphylococcus haemolyticus and their methicillin-resistance directly from blood cultures. Staphylococci clinical isolates (149) and control strains (16) previously identified by conventional methods were used to establish the multiplex PCR protocol. Subsequently, this methodology was evaluated using a fast and cheap DNA extraction protocol from 25 staphylococci positive blood cultures. A wash step of the pellet with 0.1% bovine serum albumin (BSA) solution was performed to reduce PCR inhibitors. Amplicons of 154bp (mecA gene), 271bp (S. haemolyticus mvaA gene) and 108 and 124bp (S. aureus and S. epidermidis species-specific fragments, respectively) were observed. Reliable results were obtained for 100% of the evaluated strains, suggesting that this new multiplex-PCR combined with an appropriate DNA-extraction method could be useful in the laboratory for fast and accurate identification of three staphylococci species and simultaneously their methicillin resistance directly in blood cultures.
Assuntos
Técnicas Bacteriológicas/métodos , Sangue/microbiologia , Resistência a Meticilina , Reação em Cadeia da Polimerase/métodos , Staphylococcus aureus/isolamento & purificação , Staphylococcus epidermidis/isolamento & purificação , Staphylococcus haemolyticus/isolamento & purificação , Técnicas Bacteriológicas/normas , Primers do DNA/genética , Humanos , Reação em Cadeia da Polimerase/normas , Sensibilidade e Especificidade , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus epidermidis/genética , Staphylococcus haemolyticus/efeitos dos fármacos , Staphylococcus haemolyticus/genéticaRESUMO
Staphylococcus lugdunensis are unusually virulent coagulase-negative staphylococci associated with skin infections and endocarditis. We developed an accurate and simple PCR assay to identify S. lugdunensis isolates based on detection of the fbl gene, which encodes a fibrinogen-binding protein involved in pathogen adhesion. The PCR assay was established using 16 reference strains of different Staphylococcus species and further validated with a collection of 63 clinical staphylococcal isolates that were also phenotypically characterized. Reliable results for the detection of S. lugdunensis isolates were obtained for 100% of the strains evaluated, indicating that this PCR assay can be used in the routine of microbiology laboratories as one more tool for correct species differentiation.