Espectro de agentes etiológicos associados a surtos de doenças transmitidas por alimentos em núcleos receptores turísticos de três regiões geográficas do Estado de São Paulo

Foodborne and waterborne diseases are spread by the consumption of food or water contaminated with bacteria and/or their toxins, viruses, parasites or chemicals. The aim of the research reported here was to establish the spectrum of etiologic agents of foodborne outbreaks at 15 tourist resorts in three geographic regions of the State of Sao Paulo (Brazil). The study was based on the cases reported to the Epidemic Surveillance Center (CVE) of the Public Health Authority of the State of São Paulo (SES), from 2002 to 2005. The tourist centers were chosen at random in three regions of the state (Capital, Interior and Coast) and offered the following attractions: events, agribusiness, cultural history, shopping, town center, gastronomy, health and leisure, sun and sea. Among the bacteria, the results showed that Salmonella spp. were most frequently associated with outbreaks, followed by Shigella spp., enterotoxigenic Escherichia coli, Staphylococcus aureus, Clostridium perfringens, Bacillus cereus and Campylobacter spp. Viruses (Rotavirus and Hepatitis A) played a part in many of the cases, while the frequency of parasites and worm infestations was low in the foodborne disease outbreaks at these resorts. The mixed foods (rice, beans, liver, potatoes, barbecue, juice), fish and poultry were the three commonest vehicles implicated in the outbreaks.

Vascular hyporeactivity to angiotensin II induced by Escherichia coli endotoxin is reversed by Nω-Nitro-L-Arginine, an inhibitor of nitric oxide synthase

Septic shock or sepsis is reported to be one of the major causes of death when followed by systemic infectious trauma in humans and other mammals. Its development leads to a large drop in blood pressure and a reduction in vascular responsiveness to physiological vasoconstrictors which, if not contained, can lead to death. It is proposed that this vascular response is due to the action of bacterial cell wall products released into the bloodstream by the vascular endothelium and is considered a normal response of the body's defenses against infection. A reduction in vascular reactivity to epinephrine and norepinephrine is observed under these conditions. In the present study in rats, the aim was to assess whether those effects of hypotension and hyporeactivity are also related to another endogenous vasoconstrictor, angiotensin II (AII). We evaluated the variation in the power of this vasoconstrictor over the mean arterial pressure in anesthetized rats, before and after the establishment of hypotension by Escherichia coli endotoxin (Etx). Our results show that in this model of septic shock, there is a reduction in vascular reactivity to AII and this reduction can be reversed by the inhibitor of nitric oxide synthase, Nω-Nitro-L- Arginine (NωNLA). Our results also suggest that other endogenous factors (not yet fully known) are involved in the protection of rats against septic shock, in addition to the L-arginine NO pathway.

Detecção de Escherichia coli e Salmonella spp. em microbiota intestinal de Psittaciformes em fase de reabilitação para soltura

Escherichia coli is a bacteria of the Enterobacteriacea family and it is part of the enterical microflora of mammals and of many species of birds. Salmonella spp. also belongs to the family Enterobacteriacea, it is responsible for human feed toxinfection outbreaks and usually isolated from domestic and wild birds. The present study analyzed the frequency of both agents in Psittaciformes in rehabilitation process for wildlife reintroduction. In 89 birds analyzed, 19% were infected with E. coli and 1,12% with Salmonella spp. It was carried out an analysis of the profile of antibiotic resistance in which was observed the efficiency of estreptomicin, tetraciclin, trimetoprim and gentamicin over the samples. The samples of E. coli were submitted to the Congo Red Binding test and to the Hemolisis test and 70,6% of positive samples for the first test and 53% for the second one were observed.

Contamination of cattle carcasses by Escherichia coli shiga like toxin with high antimicrobials resistence

During processing of cattle carcasses, contamination may occurs with the transfer of microbiota of animals feaces to carcasses. This contamination many times may be by Escherichia coli carriers of virulence factor as stx and eae genes being classified as Shiga like toxin. Shiga toxin-producing Escherichia coli (STEC) is recognized wordwide as human pathogen. A survey was performed to determine the sensibility profile to several antimicrobial drugs of STEC in carcasses obtained from an abattoir in Brazil between March 2008 and August at 2009. A total of 120 STEC were isolated. All isolates were confirmed as being E. coli by their biochemical analysis and submitted to polymerase chain reaction (PCR) for detection of stx, eae and ehly genes. No strains was isolated being carriers of ehly gene. The number of isolates carriers of eae gene were 48/120. The most frequent resistance was seen against cephalothin (84.0%), streptomycin (45.0%), nalidixic acid (42.0%) and tetracycline (20.0%). Multidrug resistance (MDR) to three or more antimicrobial agents was observed in 46 (38.3%) E. coli isolates. The findings of STEC and MRD show that cattle carcasses may be a reservoir of pathogenic bacterial for the consumer public. © 2011 Academic Journals.

Presence of a human diarrheagenic escherichia coli clone in captivity kept psittacidaes

Bacterial cultures of cloaca swabs from 86 captivity kept psittacidaes revealed 17 Escherichia coli bearing birds sharing strains which, on the basis of enterobacterial repetitive intergenic consensus (ERIC) PCR analysis, proved to be genetically similar. Further, triplex PCR specific for the genetic markers chuA, yjaA, and TSPE4.C2 was used to assign the strains to the E. coli reference collection (EcoR) B2 group. One strain of each, from the enteropathogenic (EPEC), enteroaggregative (EAEC) and Shiga toxin (STEC) E. coli pathovars were found among these isolates. © Marietto-Gonçalves et al.; Licensee Bentham Open.

Tethered DNA scaffolds on optical sensor platforms for detection of hipO gene from Campylobacter jejuni

DNA biosensors have gained increased attention over traditional diagnostic methods due to their fast and responsive operation and cost-effective design. The specificity of DNA biosensors relies on single-stranded oligonucleotide probes immobilized to a transduction platform. Here, we report the development of biosensors to detect the hippuricase gene (hipO) from Campylobacter jejuni using direct covalent coupling of thiol- and biotin-labeled single-stranded DNA (ssDNA) on both surface plasmon resonance (SPR) and diffraction optics technology (DOT, dotLab) transduction platforms. This is the first known report of the dotLab to detect targeted DNA. Application of 6-mercapto-1-hexanol as a spacer thiol for SPR gold surface created a self-assembled monolayer that removed unbound ssDNA and minimized non-specific detection. The detection limit of SPR sensors was shown to be 2.5 nM DNA while dotLab sensors demonstrated a slightly decreased detection limit of 5.0 nM (0.005 μM). It was possible to reuse the SPR sensor due to the negligible changes in sensor sensitivity (∼9.7 × 10 -7 ΔRU) and minimal damage to immobilized probes following use, whereas dotLab sensors could not be reused. Results indicated feasibility of optical biosensors for rapid and sensitive detection of the hipO gene of Campylobacter jejuni using specific ssDNA as a probe. © 2011 Elsevier B.V.

Expression of a new Bacillus thuringiensis Cry1Ia gene in Escherichia coli with strong activity against cotton pests

The control of cotton pests may be accomplished using Bacillus thuringiensis Cry proteins. For this purpose, the objective of this work was to evaluate the insecticidal activity of a new Cry1Ia protein against neonatal larvae of Spodoptera frugiperda and Anthonomus grandis. The complete cry1Ia gene, previously obtained by PCR with oligonucleotide primers based on the sequenced gene, was cloned into the vector pET28a(+), introduced into Escherichia coli BL21(DE3) and expressed by induction with IPTG. The expression of the Cry1Ia protein was confirmed with molecular weight of approximately 81 kDa. The results demonstrated the efficiency of the bacterial system for the expression of B. thuringiensis Cry1Ia protein, which was subsequently used in quantitative bioassays against S. frugiperda and A. grandis larvae, resulting in an extremely toxic protein for both species. This characteristic is exceptionally important for obtaining transgenic cotton plants resistant to these pests.

Effectiveness of castor oil extract on Escherichia coli and its endotoxins in root canals

The results of the present study showed a significant decrease in the number of E. coli in root canals (first collection) after irrigation with castor oil extract during biomechanical preparation. All medications tested in this study were able to eliminate E. coli in root canals; however, they could not neutralize endotoxins completely.

Antimicrobial effects of ozonated water on the sanitization of dental instruments contaminated with E. coli, S. aureus, C. albicans, or the spores of B. atrophaeus

Objectives: Ozone has been used as an alternative method for the decontamination of water, food, equipment and instruments. The objective of this study was to evaluate the antimicrobial effects of ozonated water on the sanitization of dental instruments that were contaminated by Escherichia coli, Staphylococcus aureus, Candida albicans and the spores of Bacillus atrophaeus. Methods: A total of one hundred and twenty standardized samples of diamond dental burs were experimentally contaminated with E. coli (ATCC 25922), S. aureus (ATCC 6538) and C. albicans (ATCC 18804) and the spores of B. atrophaeus (ATCC 6633) for 30min. After the contamination, the samples were exposed to ozonated water (10mg/L O3) for 10 or 30min. The control group was composed of samples that were exposed to distilled water for 30min. After the exposure to the ozonated water, 0.1mL aliquots were seeded onto BHI agar to count the colony-forming units per milliliter (CFU/mL) of E. coli, S. aureus, and B. atrophaeus. Sabouraud dextrose agar was used to count the CFU/mL of C. albicans. The results were subjected to an analysis of variance and the Tukey test. Results: For all of the microorganisms studied, the ozonated water reduced the number of CFU/mL after 10 and 30. min of sanitization, and this microbial reduction was dependent on the duration of the exposure to the ozonated water. E. coli exhibited the greatest reduction in CFU/mL (2.72-3.78. log) followed by S. aureus (2.14-3.19. log), C. albicans (1.44-2.14. log) and the spores of B. atrophaeus (1.01-1.98. log). Conclusion: The ozonated water was effective in reducing the CFU of E. coli, S. aureus, C. albicans and B. atrophaeus spores, suggesting that ozonated water can be used for the sanitization of dental instruments. © 2012 King Saud Bin Abdulaziz University for Health Sciences.

Dissection of the role of pili and type 2 and 3 secretion systems in adherence and biofilm formation of an atypical enteropathogenic escherichia coli strain

Atypical enteropathogenic Escherichia coli (aEPEC) strains are diarrheal pathogens that lack bundle-forming pilus production but possess the virulence-associated locus of enterocyte effacement. aEPEC strain 1551-2 produces localized adherence (LA) on HeLa cells; however, its isogenic intimin (eae) mutant produces a diffuse-adherence (DA) pattern. In this study, we aimed to identify the DA-associated adhesin of the 1551-2 eae mutant. Electron microscopy of 1551-2 identified rigid rod-like pili composed of an 18-kDa protein, which was identified as the major pilin subunit of type 1 pilus (T1P) by mass spectrometry analysis. Deletion of fimA in 1551-2 affected biofilm formation but had no effect on adherence properties. Analysis of secreted proteins in supernatants of this strain identified a 150-kDa protein corresponding to SslE, a type 2 secreted protein that was recently reported to be involved in biofilm formation of rabbit and human EPEC strains. However, neither adherence nor biofilm formation was affected in a 1551-2 sslE mutant. We then investigated the role of the EspA filament associated with the type 3 secretion system (T3SS) in DA by generating a double eae espA mutant. This strain was no longer adherent, strongly suggesting that the T3SS translocon is the DA adhesin. In agreement with these results, specific anti-EspA antibodies blocked adherence of the 1551-2 eae mutant. Our data support a role for intimin in LA, for the T3SS translocon in DA, and for T1P in biofilm formation, all of which may act in concert to facilitate host intestinal colonization by aEPEC strains. ©2013, American Society for Microbiology.

Associação de enterococcus faecalis, candida albicans e escherichia coli em canais radiculares e avaliação dos efeitos de extratos naturais sobre os microrganismos e endotoxinas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Condições higiênico-sanitárias de alimentos prontos para o consumo servidos em escolas públicas de um município da região noroeste do Estado de São Paulo e perfil de sensibilidade das cepas de Staphylococcus aureus e Escherichia coli isoladas frente a agentes antimicrobianos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito do pré-tratamento com amitraz sobre a febre induzida por lipopolissacarídeo (LPS) de E. coli ou interleucina-1beta (IL-1beta), em coelhos

Pós-graduação em Cirurgia Veterinária - FCAV

Ação in vitro do extrato glicólico de gengibre e medicamentos sobre Candida albicans, Enterococcus faecalis, Escherichia coli e sua endotoxina em canais radiculares

Pós-graduação em Odontologia Restauradora - ICT

Avaliação in vitro da ação de substâncias químicas auxiliares e medicações intracanais sobre Escherichia coli e sua endotoxina em canais radiculares

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