Eukaryotic ectosymbionts of Acari

The Acari is the most numerous and diverse group of the subphylum Chelicerata. With approximately 55 000 described species (and estimates of up to 1 million extant species), their adaptations for parasitism, phytophagy, mycophagy, saprophagy and predation rival other arthropods and challenge us with a wide variety of biological interactions. While a few studies have unravelled the nature of some endosymbiotic associations between mites or ticks and prokaryotes, almost nothing has been done yet regarding acarine eukaryotic ectosymbionts. Microbial ectosymbionts can benefit their hosts by providing nutrients, by aiding digestion, by enhancing communication, by assisting in mating and/or fertilization, by protecting their host against pathogenic microorganisms, against predation and so on. In this sketch, we introduce a number of described cases of fungal and protist ectosymbionts and discuss the role they might play in the life of their acarine hosts.

1,4-Diamino-2-butanone, a wide-spectrum microbicide, yields reactive species by metal-catalyzed oxidation

The alpha-aminoketone 1,4-diamino-2-butanone (DAB), a putrescine analogue, is highly toxic to various microorganisms, including Trypanosoma cruzi. However, little is known about the molecular mechanisms underlying DAB`s cytotoxic properties. We report here that DAB (pK(a) 7.5 and 9.5) undergoes aerobic oxidation in phosphate buffer, pH 7.4, at 37 degrees C, catalyzed by Fe(II) and Cu(II) ions yielding NH(4)(+) ion, H(2)O(2), and 4-amino-2-oxobutanal (oxoDAB). OxoDAB, like methylglyoxal and other alpha-oxoaldehydes, is expected to cause protein aggregation and nucleobase lesions. Propagation of DAB oxidation by superoxide radical was confirmed by the inhibitory effect of added SOD (50 U ml(-1)) and stimulatory effect of xanthine/xanthine oxidase, a source of superoxide radical. EPR spin trapping studies with 5,5-dimethyl-1-pyrroline-1-oxide (DMPO) revealed an adduct attributable to DMPO-HO(center dot), and those with alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone or 3,5-dibromo-4-nitrosobenzenesulfonic acid, a six-line adduct assignable to a DAB(center dot) resonant enoyl radical adduct. Added horse spleen ferritin (HoSF) and bovine apo-transferrin underwent oxidative changes in tryptophan residues in the presence of 1.0-10 mM DAB. Iron release from HoSF was observed as well. Assays performed with fluorescein-encapsulated liposomes of cardiolipin and phosphatidylcholine (20:80) incubated with DAB resulted in extensive lipid peroxidation and consequent vesicle permeabilization. DAB (0-10 mM) administration to cultured LLC-MK2 epithelial cells caused a decline in cell viability, which was inhibited by preaddition of either catalase (4.5 mu M) or aminoguanidine (25 mM). Our findings support the hypothesis that DAB toxicity to several pathogenic microorganisms previously described may involve not only reported inhibition of polyamine metabolism but also DAB pro-oxidant activity. (C) 2011 Elsevier Inc. All rights reserved.

Avaliação do potencial de formigas (Hymenoptera: formicidae) como vetores mecânicos de bactérias do gêneroSstaphylococcus no ambiente hospitalar.

In a hospital environment, these bacteria can be spread by insects such as ants, which are characterized by high adaptability to the urban environment. Staphylococcus is a leading cause of hospital infection. In Europe, Latin America, USA and Canada, the group of coagulase negative staphylococci (CoNS) is the second leading cause of these infections, according to SENTRY (antimicrobial surveillance program- EUA). In this study, we investigated the potential of ants (Hymenoptera: Formicidae) as vehicle mechanics of Staphylococcus bacteria in a public hospital, in Natal-RN. The ants were collected, day and night, from June 2007 to may 2008, in the following sectors: hospitals, laundry, kitchen, blood bank. The ants were identified according to the identification key of Bolton, 1997. For the analysis of staphylococci, the ants were incubated in broth Tryptic Soy Broth (TSB) for 24 hours at 35 º C and then incubated on Mannitol Salt Agar. The typical colonies of staphylococci incubated for 24 hours at 35 ° C in Tryptic Soy Agar for the characterization tests (Gram stain, catalase, susceptibility to bacitracin and free coagulase). The identification of CoNS was performed through biochemical tests: susceptibility to novobiocin, growth under anaerobic conditions, presence of urease, the ornithine decarboxylation and acid production from the sugars mannose, maltose, trehalose, mannitol and xylose. The antimicrobial susceptibility examined by disk-diffusion technique. The technique of Polymerase Chain Reaction was used to confirm the presence of mecA gene and the ability to produce biofilm was verified by testing in vitro using polystyrene inert surface, in samples of resistant staphylococci. Among 440 ants, 85 (19.1%) were carrying coagulase-negative staphylococci (CoNS) of the species Staphylococcus saprophyticus (17), Staphylococcus epidermidis (15), Staphylococcus xylosus (13), Staphylococcus hominis hominis (10), Staphylococcus lugdunensis (10), Staphylococcus warneri (6), Staphylococcus cohnii urealyticum (5), Staphylococcus haemolyticus (3), Staphylococcus simulans (3), Staphylococcus cohnii cohnii (2), and Staphylococcus capitis (1). No Staphylococcus aureus was found. Among the isolates, 30.58% showed resistance to erythromycin. Two samples of CoNS (2.35%), obtained from the ant Tapinoma melanocephalum collected in the post-surgical female ward, S. Hominis hominis and S. lugdunensis harbored the mecA gene and were resistant to multiple antibiotics, and the specie S. hominis hominis even showed to be a biofilm producer. This study proves that ants act as carriers of multidrug-resistant coagulase-negative Staphylococci and biofilm producers and points to the risk of the spreading of pathogenic microorganisms by this insect in the hospital environment

Potential microbiological contamination of effluents in poultry and swine abattoirs

Health risks in the effluents of seven swine abattoirs and of seven poultry abattoirs were evaluated with regard to environment degradation and to dissemination of pathogenic microorganisms during the rainy and dry seasons. Supply-water samples from affluents and effluents of the treatment systems at different sites within the abattoir processing system were analysed. Similarly, water samples from the three recipient sites (emission point, 100 m upstream, 100 m downstream) were also analysed. Temperature, free residual chlorine (FRC), total coliform bacteria, Escherichia coli, enterococci, identification and serotyping of salmonellae were assessed. Scalding is the most significant stage in the slaughtering chain (P<0.05) when temperature is taken into account. Temperatures Lit effluents and at the sampled sites in the water bodies accorded to state and federal legislation standards. Supply waters did not meet the standards for FRC and microbial count standards according to the Ministry of Health and within limits imposed by the Industrial and Sanitary Inspection Regulations for Animal Products. Feather plucking and evisceration in Poultry slaughter and the cleansing of carcasses and facilities in Poultry and swine slaughtering had the highest contamination impact. The three loci at the water bodies were above the microbiological standards for classes II and III sites, in conformity with Law 8468 of the state of São Paulo, Brazil and Conama. Salmonella was found at several sites during slaughter, at both types of abattoirs, including in the effluent treatment system. This showed that these sites were the dissemination sources of the microorganism.

Avaliação clínica e microbiológica da mucosa oral de crianças com leucemia linfoblástica aguda, submetidas à ação profilática do gluconato de clorexidina A 0,12%

Regarding the morbidity potential of oral complications in patients with leukemia, it evaluated the clínical and microbiologic changes of oral mucosal in children with LLA, with age range of O to 15 years old, undergone the chemotherapy antineoplastic and for the use prophylactic of chlorhexidine gluconate 0,12% during ten days, that was utilized in each chemotherapy treatment stage. The collect for rnicrobiological study was obtained preferentiality in intensification stage at the end prophylatic treatment. The study grouup had 20 children, where it observed clinically decrease in frequency of mucositis, with 8 cases (40%) only. In microbiological examination observed one reduced incidence of pathogenic microorganisms with Staphylococcus coagulase- negative (40%), Klebsiella pneumoniae (5%), Escherichia coZi enteropathogenic (15%), Stenotrophomonas maltophilia (5%) e Candida albicans (35%). The findings obtained in the present trial suggest that the use of chlorhexidine gluconate 0,12% can be responsible for incidence reduced of mucositis, but it wasn t possible to make correlation between isolated pathogenic microorganisms and mucositis development

NF-kappa B signaling modulation by EBV and KSHV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Sequencing and expression analysis of hepcidin mRNA in donkey (Equus asinus) liver

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Associação deagentes patogênicos isolados emanálise microbiológica da água, coma presença de mastite clínica ou subclínica, em vacas de propriedades leiteiras da região de Cerqueira César - SP

Objetivou-se, neste trabalho, pesquisar a relação entre os microrganismos patogênicos isolados e identificados em água utilizada na ordenha, com o isolamento e identificação dos mesmos em amostras de leite, de quartos mamários apresentando mastite clínica ou subclínica nas mesmas propriedades. Foram utilizadas 16 propriedades rurais leiteiras, escolhidas aleatoriamente, na região de Cerqueira César - SP, que utilizavam ordenha mecânica. A água utilizada na ordenha foi classificada em relação à presença de coliformes totais e fecais, como dentro dos padrões ou fora dos padrões de potabilidade humana. Nos resultados obtidos, 94% das amostras foram classificadas como fora dos padrões em relação a coliformes totais e fecais. Os microrganismos identificados foram: Escherichia coli (51%), Enterobacter spp. (25%), Enterobacter cloacae (8%) Edwardsiella tarda (8%) e Klebsiella oxytoca (8%). em relação ao leite, foram analisadas 373 amostras provenientes de vacas em lactação, com mastite clínica (n=19; 5%) e subclínica (n=354; 95%). Os animais com mastite subclínica foram identificados pela contagem de células somáticas (CCS), utilizando-se o aparelho eletrônico (Somacount 300, Bentley), onde a média observada foi de 1.631 x 10³ células/mL. Os principais microrganismos identificados foram: Staphylococcus aureus (30%), Corynebacterium bovis (23%) e Staphylococcus spp. (15%). Conforme os dados obtidos, os agentes coliformes encontrados na água, utilizada na ordenha, não estavam presentes nas análises das amostras de leite dos quartos mamários com mastite clínica ou subclínica das respectivas propriedades, demonstrando não haver associação entre a qualidade da água e a ocorrência de mastite.

Staphylococcus Aureus Contamination in a Pediatric Dental Clinic

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Fungos causadores de podridões pós-colheita em uvas apirênicas no pólo agrícola de Juazeiro - BA e Petrolina - PE

In Brazil, postharvest diseases caused by pathogenic microorganisms are a major problem that causes damage to around 80% of the total fruit production. In the lower middle Sao Francisco river valley numerous studies on identification and control of fungal diseases during postharvest of grapes are needed, in order to minimize losses in this step. In this context, bunches of seedless varieties 'Crimson', 'Sonaka'; 'Superior' and 'Thompson' were collected from July to November 2009, in order to identify and quantify the incidence of pathogenic fungi. The grapes were collected on five farms which specialize in the production of table grapes for export, all located in Juazeiro - BA and Petrolina - PE. During this period, 10 samples were taken. In the fruit farm five plants were used for sampling, and removal of two bunches of grapes per plant, totaling 10 bunches per variety. Subsequently, they were sent to the laboratory of Plant Pathology at UNEB/DTCS where they were placed separately in a moist chamber for 48 hours at an average temperature of 23 degrees C. After this period, isolations of berries and stems in Petri plates containing PDA - potato-dextrose-agar were carried out with 10 repetitions, which were placed on benches under laboratory conditions. From the 8th day on, the presence of Aspergillus niger, Alternaria alternata, Cladosporium herbarum, Lasiodiploidia theobromae was observed, which presented the highest incidence, as well as Rhizopus stolonifer, Penicillium expansum.

Inhibitory effect of essential oils against Lactobacillus rhamnosus and starter culture in fermented milk during its shelf-life period

The use of essential oils in foods has attracted great interest, due to their antagonistic action against pathogenic microorganisms. However, this action is undesirable for probiotic foods, as products containing Lactobacillus rhamnosus. The aim of the present study was to measure the sensitivity profile of L. rhamnosus and a yogurt starter culture in fermented milk, upon addition of increasing concentrations of cinnamon, clove and mint essential oils. Essential oils were prepared by steam distillation, and chemically characterised by gas chromatography-mass spectrometry (GC-MS) and determination of density. Survival curves were obtained from counts of L. rhamnosus and the starter culture (alone and in combination), upon addition of 0.04% essential oils. In parallel, titratable acidity was monitored over 28 experimental days. Minimum inhibitory concentration values, obtained using the microdilution method in Brain Heart Infusion medium, were 0.025, 0.2 and 0.4% for cinnamon, clove and mint essential oils, respectively. Cinnamon essential oil had the highest antimicrobial activity, especially against the starter culture, interfering with lactic acid production. Although viable cell counts of L. rhamnosus were lower following treatment with all 3 essential oils, relative to controls, these results were not statistically significant; in addition, cell counts remained greater than the minimum count of 10(8)CFU/mL required for a product to be considered a probiotic. Thus, although use of cinnamon essential oil in yogurt makes starter culture fermentation unfeasible, it does not prevent the application of L. rhamnosus to probiotic fermented milk. Furthermore, clove and mint essential oil caused sublethal stress to L. rhamnosus.

Ballast water: a review of the impact on the world public health

Since the nineteenth century ships have been using ballast water (BW) for safety, stability, propulsion and maneuverability, as well as to redress loss of fuel weight and water consumption, and to maintain structural stress at acceptable levels. Ballast water has been spreading many non-native species around the globe, but little is known about the extent and potential significance of ship-mediated transfer of microorganisms. The global movements of ballast water by ships create a long-distance dispersal mechanism for human pathogens that may be important in the worldwide distribution of microorganisms, as well as for the epidemiology of waterborne diseases. Only a few studies have been carried out on this subject, most of them involving ballast water containing crustacean larvae and phytoplankton. Specialized microbiological studies on these waters are necessary to avoid a repeat of what happened in 1991, when epidemic cholera was reported in Peru and rapidly spread through Latin America and Mexico. In July of 1992, Vibrio cholerae was found in the USA and the Food and Drug Administration (FDA) determined that it came from ballast water of ships whose last port of call was in South America. In Brazil, just a few studies about the subject have been performed. An exploratory study by the Brazilian National Health Surveillance Agency (Agencia Nacional de Vigilancia Sanitaria - ANVISA) found in ballast water different microorganisms, such as fecal coliforms, Escherichia coli, Enterococcus faecalis, Clostridium perfringens, coliphages, Vibrio cholerae O1 and Vibrio cholerae non-O1. Until now, Brazil has been focusing only on organisms transported to its territory from other countries by ballast water, to avoid their establishment and dissemination in Brazilian areas. Studies that can assess the probability that water ballast carries pathogenic microorganisms are extremely important, as is the examination of ships that arrive in the country. Treatment of the human infections caused by BW exists but none is completely safe and efficient.

Biological properties of medicinal plants: a review of their antimicrobial activity

Plants have been used for thousands of years to flavor and conserve food, to treat health disorders and to prevent diseases including epidemics. The knowledge of their healing properties has been transmitted over the centuries within and among human communities. Active compounds produced during secondary vegetal metabolism are usually responsible for the biological properties of some plant species used throughout the globe for various purposes, including treatment of infectious diseases. Currently, data on the antimicrobial activity of numerous plants, so far considered empirical, have been scientifically confirmed, concomitantly with the increasing number of reports on pathogenic microorganisms resistant to antimicrobials. Products derived from plants may potentially control microbial growth in diverse situations and in the specific case of disease treatment, numerous studies have aimed to describe the chemical composition of these plant antimicrobials and the mechanisms involved in microbial growth inhibition, either separately or associated with conventional antimicrobials. Thus, in the present work, medicinal plants with emphasis on their antimicrobial properties are reviewed.

Microbiological quality of salmon (Salmo salar) sold in cities of the state of São Paulo, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Microbiological counting in lamb carcasses from an abattoir in São Paulo, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)