RESUMO
The objective of this study was to identify the main extended-spectrum beta-lactamase (ESBL)-producing bacteria and to detect the frequency of the major genes responsible to trigger this resistance in hospitalized animals. We collected 106 rectal swabs from cats (n = 25) and dogs (n = 81) to detect ESBL-producing isolates. ESBL-positive samples were submitted to the antimicrobial susceptibility test, and polymerase chain reaction was performed to detect TEM, SHV, and CTX-M genes from different groups. We observed that 44.34% of these samples (11 cats and 36 dogs) were positive for ESBL-producing bacteria. Thirteen animals (27.66%-seven cats and six dogs) were hospitalized for elective castration (healthy animals). Only a single animal was positive for ESBL-producing bacteria at hospital admission (the animal also showed an ESBL-positive isolate after leaving the hospital), whereas 11 were positive only at the hospital discharge. Of the 73 ESBL-producing isolates, 13 were isolated from cats (8 sick and 7 healthy) and 60 from dogs (53 sick and 7 healthy). Escherichia coli was the major ESBL-producing bacterium isolated (53.42%), followed by Pseudomonas aeruginosa (15.07%), Salmonella sp., and Proteus mirabilis (5.48% each one). Antimicrobial resistance profile of ESBL-producing isolates showed that 67 isolates (91.78%) were resistant to 3 or more antibiotic classes, while 13 of them (17.81%-2 healthy cats and 11 sick dogs) were resistant to all tested antimicrobial classes. The blaTEM gene exhibited the highest frequency in ESBL-producing isolates, followed by the blaCTX-M group 8/25, blaCTX-M group 1 and blaCTX-M group 9 genes. These results are useful to assess the predominance of ESBL-producing isolates recovered from dogs and in cats in Brazil. Consequently, we draw attention to these animals, as they can act as reservoirs for these microorganisms, which are the major pathogens of nosocomial infections worldwide.
Assuntos
Infecções Bacterianas/veterinária , Doenças do Gato/microbiologia , Doenças do Cão/microbiologia , beta-Lactamases/biossíntese , Animais , Infecções Bacterianas/enzimologia , Infecções Bacterianas/genética , Proteínas de Bactérias , Doenças do Gato/genética , Gatos , Doenças do Cão/genética , Cães , Farmacorresistência Bacteriana Múltipla/genética , Genes Bacterianos , Hospitais Veterinários , beta-Lactamases/genéticaRESUMO
Phagocytes, such as granulocytes and monocytes/macrophages, contain a membrane-associated NADPH oxidase that produces superoxide leading to other reactive oxygen species with microbicidal, tumoricidal and inflammatory activities. Primary defects in oxidase activity in chronic granulomatous disease (CGD) lead to severe, life-threatening infections that demonstrate the importance of the oxygen-dependent microbicidal system in host defence. Other immunological disturbances may secondarily affect the NADPH oxidase system, impair the microbicidal activity of phagocytes and predispose the host to recurrent infections. This article reviews the primary defects of the human NADPH oxidase leading to classical CGD, and more recently discovered immunological defects secondarily affecting phagocyte respiratory burst function and resulting in primary immunodeficiencies with varied phenotypes, including susceptibilities to pyogenic or mycobacterial infections.
Assuntos
Doença Granulomatosa Crônica/enzimologia , NADPH Oxidases/imunologia , Fagócitos/enzimologia , Explosão Respiratória/imunologia , Infecções Bacterianas/enzimologia , Infecções Bacterianas/imunologia , Doença Granulomatosa Crônica/imunologia , Doença Granulomatosa Crônica/microbiologia , Humanos , Mutação , NADPH Oxidases/genética , Fagócitos/imunologia , Fagócitos/microbiologiaRESUMO
Nitric oxide (NO) derived from inducible nitric oxide synthase (iNOS) plays an important role in host defense, as well as in inflammation-induced tissue lesions. Here we evaluated the role of NO in bone loss in bacterial infection-induced apical periodontitis by using iNOS-deficient mice (iNOS(-/-)). The iNOS(-/-) mice developed greater inflammatory cell recruitment and osteolytic lesions than WT mice. Moreover, tartrate-resistant acid-phosphatase-positive (TRAP(+)) osteoclasts were significantly more numerous in iNOS(-/-) mice. Furthermore, the increased bone resorption in iNOS(-/-) mice also correlated with the increased expression of receptor activator NF-kappaB (RANK), stromal-cell-derived factor-1 alpha (SDF-1 alpha/CXCL12), and reduced expression of osteoprotegerin (OPG). These results show that NO deficiency was associated with an imbalance of bone-resorption-modulating factors, leading to severe infection-stimulated bone loss.
Assuntos
Perda do Osso Alveolar/enzimologia , Infecções Bacterianas/enzimologia , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico/metabolismo , Periodontite Periapical/enzimologia , Fosfatase Ácida/análise , Actinomicose/enzimologia , Perda do Osso Alveolar/patologia , Animais , Infecções por Bacteroidaceae/enzimologia , Biomarcadores/análise , Contagem de Células , Movimento Celular , Quimiocina CXCL12/análise , Exposição da Polpa Dentária/microbiologia , Isoenzimas/análise , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Osteoclastos/patologia , Osteólise/metabolismo , Osteólise/patologia , Osteoprotegerina/análise , Periodontite Periapical/patologia , Ligante RANK/análise , Receptor Ativador de Fator Nuclear kappa-B/análise , Fosfatase Ácida Resistente a TartaratoRESUMO
The incidence of strains producing transferable beta-lactamases capable of hydrolyzing third generation cephalosporins or aminothiazole-oximino substituted monobactams in five Buenos Aires hospitals during a four month period was studied. These enzymes were categorized by 1) MIC greater than or equal to 1 mg/l for third generation cephalosporins; 2) MIC less than 0.06 mg/l for third generation cephalosporins combined with clavulanic acid or sulbactam; 3) sensitivity to imipenem or cephamycins (excluding permeability mutants); and 4) transferable resistance by conjugation. Beta-lactamases hydrolyzing aminothiazole-oximino substituted monobactams were produced by 17.2% of Enterobacteriaceae from intensive care unit patients; 3.6% from inpatients of other units and 1.2% from outpatients. Producers were mainly Klebsiella spp. (45/46) resistant to aminoglycosides (most of them AAC 3'-AAC 6' producers). Three strains had a an isoelectric point of 6.0, two of 6.5 and three of 7.7. TEM-1 beta-lactamase (isoelectric point 5.4) was detected in 6/8 strains. An inocolum effect was observed in 40/46 strains. A Klebsiella pneumoniae strain preserved since 1982 also produced a transferable beta-lactamase hydrolyzing aminothiazole-oximino substituted monobactams.
Assuntos
Infecções Bacterianas/enzimologia , beta-Lactamases/biossíntese , Adulto , Argentina/epidemiologia , Infecções Bacterianas/classificação , Infecções Bacterianas/epidemiologia , Conjugação Genética , Resistência Microbiana a Medicamentos/genética , Humanos , Hidrólise , Incidência , Recém-Nascido , Testes de Sensibilidade Microbiana , beta-Lactamases/classificação , beta-Lactamases/genéticaRESUMO
Se describe el ensayo de laboratorio y uso de la enzima 2'-5' oligoadenilato sintetasa (2'-5' OAS) en el diagnóstico diferencial de infecciones virales de infecciones bacterianas. La enzima 2'-5' OAS se ensayó en extractos solubles de linfocitos de sangre periférica en 73 pacientes: 28 controles, 11 pacientes con infección bacteriana aguda confirmada y 34 pacientes con infecciones virales, documentadas por el cuadro clínico y/o de laboratorio. La actividad de la enzima 2'-5'OAS en cada grupo se comparó en términos de porcentaje de aumento con respecto a la incorporación basal de 3H-ATP. Los linfocitos de pacientes con infecciones virales tienen un 377,9ñ195,3% de aumento de actividad 2'-5'OAS; las infecciones bacterianas alcanzan a un 98,2ñ53,2%. El ensayo enzimático que se describe, ha resultado particularmente útil para diferenciar orígenes etiológicos en el síndrome febril prolongado