Qualidade microbiológica de pescado comercializado em feiras livres de Palmas - TO / Microbiological quality of fish marketed in Palmas - TO

O pescado é um dos alimentos mais suscetíveis à deterioração. O objetivo desse trabalho foi avaliar a qualidade microbiológica e temperatura da Caranha (Piaractus mesopotamicus) em 27 amostras, Tambaqui (Colossoma macropomum) em 22 amostras e Tucunaré (Cichla sp.) em 2 amostras, comercializados em feiras livres pesando de 1 a 1,5 kg e analisar quanto à presença de Salmonella sp., Estafilococos coagulase positiva, Número Mais Provável de Coliformes totais e termotolerantes, Contagem total de bactérias Mesófilas e Contagem total de bactérias Psicrotróficas. Detectou-se Salmonella sp. em 11,1% das amostras de Caranha e 4,5% das amostras de Tambaqui; para coliformes a 45 °C, 14,8% das amostras de Caranha e 77,2% das amostras de Tambaqui apresentaram- se inadequadas, contudo todas as amostras estavam de acordo com a legislação para Estafilococos coagulase positiva. Foram encontradas bactérias Mesófilas e Psicrotróficas, sendo a temperatura inadequada em 22,2% das amostras de Caranha e 81,8% das amostras de Tambaqui, constatando assim, falhas no processo de armazenamento, manipulação e ausência de refrigeração.

Molecular epidemiology of coagulase-negative bloodstream isolates: detection of Staphylococcus epidermidis ST2, ST7 and linezolid-resistant ST23

Abstract The mechanisms contributing to persistence of coagulase-negative staphylococci are diverse; to better understanding of their dynamics, the characterization of nosocomial isolates is needed. Our aim was to characterize phenotypic and molecular characteristics of Staphylococcus epidermidis and Staphylococcus haemolyticus human blood isolates from two tertiary care hospitals in Mexico, the Hospital Universitario in Monterrey and the Hospital Civil in Guadalajara. Antimicrobial susceptibility was determined. Biofilm formation was assessed by crystal violet staining. Detection of the ica operon and Staphylococcal Cassette Chromosome mec typing were performed by PCR. Clonal relatedness was determined by Pulsed-fiel gel electrophoresis and Multi locus sequence typing. Methicillin-resistance was 85.5% and 93.2% for S. epidermidis and S. haemolyticus, respectively. Both species showed resistance >70% to norfloxacin, clindamycin, levofloxacin, trimethoprim/sulfamethoxazole, and erythromycin. Three S. epidermidis and two S. haemolyticus isolates were linezolid-resistant (one isolate of each species was cfr+). Most isolates of both species were strong biofilm producers (92.8% of S. epidermidis and 72.9% of S. haemolyticus). The ica operon was amplified in 36 (43.4%) S. epidermidis isolates. SCCmec type IV was found in 47.2% of the S. epidermidis isolates and SCCmec type V in 14.5% of S. haemolyticus isolates. No clonal relatedness was found in either species. Resistance to clindamycin, levofloxacin, erythromycin, oxacillin, and cefoxitin was associated with biofilm production for both species (p < 0.05). A G2576T mutation in 23S rRNA gene was detected in an S. haemolyticus linezolid-resistant isolate. All linezolid-resistant S. epidermidis isolates belonged to ST23; isolate with SCCmec type IV belonged to ST7, and isolate with SCCmec type III belonged to ST2. This is the first report of ST7 in Mexico. There was a high genetic diversity in both species, though both species shared characteristics that may contibute to virulence.

Influence of carvacrol and thymol on the physiological attributes, enterotoxin production and surface characteristics of Staphylococcus aureus strains isolated from foods

This study evaluated the influence of the phenolic compounds carvacrol (CAR) and thymol (THY) on some physiological characteristics and on the modulation of the secretion of some staphylococcal virulence factors, that is, coagulase and enterotoxin. This study also investigated possible mechanisms for the establishment of the anti-staphylococcal activity of these compounds. Sublethal concentrations (0.3 and 0.15 µL/mL) of CAR and THY inhibited the activity of the enzymes coagulase and lipase and led to a decrease in salt tolerance. At the tested sublethal concentrations, both CAR and THY led to a total suppression of enterotoxin production. The loss of a 260-nm-absorbing material and an efflux of potassium ions occurred immediately after the addition of CAR and THY at 0.6 and 1.2 µL/mL and increased up to 120 min of exposure. Electron microscopy of cells exposed to CAR and THY (0.6 µL/mL) revealed that individual cells appeared to be deformed, with projections of cellular material. The observations of leakage of cellular material and an altered cell surface suggest that gross damage to a cell's cytoplasmic membrane, which results in a disruption in protein secretion, could be responsible for the anti-staphylococcal properties of CAR and THY.

Prevalence, aetiology and antibiotic resistance profiles of coagulase negative staphylococci isolated in a teaching hospital

In this paper we carried out a study about prevalence of the clinically significant coagulase negative staphylococcal (CNS) isolates found in an university hospital. Two hundred four CNS isolates from 191 patients obtained between the period of 1998 to 2002, were studied. About 27 percent (52/191) of the infection cases studied were confirmed as CNS-associated diseases. Blood stream infection (BSI) was the most frequent CNS associated-disease (25 percent; 13/52). The great majority of the BSI was verified in the Neonatal Intensive Care Unit (NICU). The analysis of the 52 patients medical history showed that 85 percent of the BSI was acquired in hospital. Most of the CNS nosocomial infections were associated with the use of indwelling medical devices. The incidence of methicillin-resistance among significant CNS isolates was 38 percent. In this study, a high percentage of exogenous contaminant was verified (60 percent), indicating that contamination of clinical specimens during sample collection is critical.

Detection of enterotoxin genes of Staphylococcus sp isolated from nasal cavities and hands of food handlers

Food handlers, an important factor in food quality, may contain bacteria that are able to cause foodborne disease. The present study aimed to research coagulase-negative (CNS) and -positive staphylococci (CPS) in 82 food handlers, analyzing nasal and hand swabs, with identification of 62 CNS (75.6 percent) and 20 CPS strains (24.4 percent). Staphylococcal enterotoxins genes were investigated by PCR. In 20 CPS strains, 19 were positive for one or more genes. The percentage of CNS presenting genes for enterotoxins was high (46.8 percent). Despite of the staphylococcal species, the most common gene was sea (35.4 percent), followed by seh and sej (29.2 percent). The detection of new staphylococcal enterotoxins (SEs) genes showed a higher pathogenic potential in this genus. The presence of these gene points out the importance of CNS not only as contaminant bacteria but also as a pathogen.

Perfil celular e microbiológico do leite de ovelhas Santa Inês no período lactante e pós-desmame / Cellular and microbiological profile of Santa Ines ewes in the lactation and the post-weaning period

The aim was to evaluate and compare the microbiological and cellular profile of the milk of Santa Ines ewes during the lactation period and the active involution. Milk samples were analyzed from 12 ewes during these distinct periods. Clinical examination of the mammary gland, somatic cell count (SCC), California Mastitis Test (CMT), bacteriologic screening and sensibility of the pathogens in vitro were performed. Most alterations were observed in the active involution period. SCC and CMT were higher in this same period. Besides this, a high persistency of infection occurred. The active involution period did not show high susceptibility. Coagulase-negative staphylococci were the only isolated bacteria. A high antimicrobial sensibility of these pathogens was also encountered.

O objetivo deste trabalho foi avaliar o perfil microbiológico e celular do leite no período lactante e de involução ativa de ovelhas da raça Santa Inês. Foram avaliadas amostras lácteas de 12 ovelhas durante estes distintos períodos. Realizou-se o exame físico da mama, sendo as amostras lácteas submetidas à contagem de células somáticas (CCS), ao California Mastitis Test (CMT), ao exame microbiológico e aos testes de sensibilidade in vitro dos patógenos encontrados. Foram observados maiores escores do exame físico, CCS, CMT durante o período de involução ativa, além de uma alta persistência da infecção durante estes períodos. O período de involução ativa não se mostrou como um momento de alta susceptilidade. Os estafilococos coagulase negativa representaram o único gênero isolado das glândulas infectadas. Uma alta sensibilidade dos agentes etiológicos envolvidos frente aos diferentes antimicrobianos in vitro foi também observada.

Detecção da produção de slime por estafilococos coagulase-negativa isolados de cateter venoso central / Detection of slime production by coagulase-negative staphylococci isolated from central venous catheter

A produção de slime é um importante fator de virulência dos estafilococos coagulase-negativa, permitindo-lhes aderir sobre as superfícies lisas de biomateriais, e por isso, é associada aos processos de infecção de implantes. No presente estudo a produção de slime em 27 cepas de estafilococos coagulase-negativa foi investigada por cultura em ágar vermelho Congo (77,7% de positividade), método espectrofotométrico ou damicroplaca (81,4% de positividade) e microscopia eletrônica de varredura (88,9% de positividade). Foi também avaliada a resistência de estafilococos coagula-se negativa a vários antimicrobianos usando a técnica do disco difusão. A porcentagem de resistência à penicilina G, oxacilina, eritromicina, clindamicina e gentamicinaem estafilococos produtores de slime foi respectivamente de 88,9%; 70,4%; 81,5%; 66,7% e 59,2%; todos os estafilococos coagulase-negativa foram vancomicina sensíveis. As cepas isoladas de cateter venoso central foram identificadas por método convencional e sistema API Staph. Os 27 estafilococos coagulase-negativa foram identificados como: S. saprophyticus (3,7%), S. xylosus(7,4%), S. haemolyticus (14,8%), S. epidermidis (37,0%), S. warneri (14,8%), S. lugdunensis (7,4%), S. hominis (7,4%), S. schleiferi (3,7%) e S. chromogenes (3,7%). Pode-se concluir que entre a maioria das espécies Staphylococcus coagulase-negativa houve associação entre a produção de slime, origem nosocomial das cepase reduzida sensibilidade aos antimicrobianos, sugerindo potencial patogênico no ambiente hospitalar.

Slime production is an important virulence factor of coagulase-negative Staphylococcus spp., allowing them to attach to smooth surfaces of biomaterials, and it has been associated with infections of implanted medical devices. In the present study the production of slime capsules in 27 strains of coagulase-negative Staphylococcus was investigated by culture in Congo Red agar (77.7% positivity), spectrophotometric or microplate method (81.4% positivity) and scanning electron microscopy (88.9% positivity). The resistance of coagulase-negative strains of Staphylococcus to various antimicrobial agents was also determined by agar disk diffusion. The proportion of strains resistant to penicillin G, oxacillin, erythromycin, clindamycin and gentamicin among the slime-producing staphylococci was 88.9%, 70.4%, 81.5%, 66.7% and 59.2%, respectively; all of the coagulase-negative staphylococci were susceptible to vancomycin. The strains isolated from central venous catheters were identified by a conventional method and the API Staph system. The 27 coagulase-negative taphylococcus strains were identified as: S. saprophyticus (3.7%), S. xylosus (7.4%), S. haemolyticus (14.8%), S. epidermidis (37.0%), S. warneri (14.8%), S. lugdunensis (7.4%), S. hominis (7.4%), S. schleiferi (3.7%) and S. chromogenes (3.7%). It can be concluded that in the most of the coagulase-negative Staphylococcus species there was an association between slime production, the nosocomial origin of the strains and reduced sensitivity to the antibiotics, suggesting a pathogenic potential in the hospital environment.

Tipificación de estafilococos coagulasa negativa resistentes a la novobicina aislados de muestras clínicas / Standardisation of isolated resistant estafilococos coagulasa negative to the novobicina of clinical samples

Estudio realizado a 44 cepas para conocer la especie estafilococos coagulasa negativa (ECN) resistentes a la novobiocina

Identificación de stapylococcus coagulasa negativa aislados del hombre en la ciudad de Valdivia, Chile / Identification of coagulase negative staphylococci from man in Valdivia, Chile

Actualmente , se reconocen 32 especies de Staphylococcus y 8 variedades. La mitad se aisla del hombre, siendo su hábitat el ecosistema cutáneo. Muchas de estas especies son reportadas, produciendo diferentes cuadros, sea por su capacidad de adhesión, como también por los factores predisponentes del huésped y multirresistencia. Poca es la información, al respecto, en Chile. Se identificaron 106 de Staphylococcus coagulasa negativa (SNC), correspondio el 57,5 por ciento a S. epidermidis, el 11,3 por ciento a S. lugdunesis, 6,6 por ciento a S. saprophyticus. Se aisló también S. auricularis, S. cohnii, S. capitis ssp. ureolyticus, S. schleiferi y S. simulans. Se insiste en la correcta identificación de las especies. Los esquemas en uso conducen a error

Características clínico-epidemiológicas de la estafilococcemia / Clinic epidemiological characteristics in staphylococcaemia

Con el propósito de conocer las características clínicas y epidemiológicas de la estafilococcemia, realizamos un estudio observacional en la Clínica Infantil Dr. Robert Read Cabral durante el período abril 1994 a marzo 1995. En total se incluyeron 30 pacientes con estafilococcemia, de los cuales, la mayor frecuencia correspondió al grupo etáreo comprendido entre 2 a 5 años con 13.43//; el sexo más afectado fue el masculino con 18 casos, 60//. El 80// vivía en hacinamiento. El Staphylococcus aureus (coagulasa positivo) se encontró en el 96.6// de los cultivos de sangre. Todos los estafilococos fueron sensibles a la oxacilina y resistentes a la penicilina; la letalidad fue de 23.3//