Multi-virulence of Campylobacter jejuni carried by chicken meat in Brazil.

Campylobacter jejuni is the most frequent cause of bacterial gastroenteritis; therefore, the characteristics of its epidemiology must be continuously investigated to support possible mitigating measures. This is particularly important when evaluating representative strains from the world's leading chicken meat exporter, Brazil. We evaluated a panel of 14 virulence genes in 359 strains of C. jejuni isolated from chilled broiler carcasses in Brazil. The genes were classified into five virulence categories (B: biofilm/motility; SS: secretion/cytotoxicity system; CI: invasion/colonization; GB: Guillain-Barré; and AE: adaptation to stress). The percentage of strains with stress adaptation genes (86.07%) indicates the ability to survive in unfavorable environments; in addition, the strains showed a risk of causing infections in humans due to the frequency of the hcp gene (97.77%). Genes related to Guillain-Barre syndrome (GBS) in 77.44% of strains are an additional concern, which must be monitored. The gene panel showed the presence of 124 virulence profiles. Individual analyses by carcass, slaughter establishment, and municipalities in which they were located showed high index variabilities (I.Var.) of 0.82, 0.87, and 0.78, respectively. Georeferencing indicated the state of Paraná as a hotspot for virulent strains. Higher levels of isolation and multi-virulence were identified in the summer, which is hot and humid in Brazil. Together, our results showed that the studied strains are a potential danger to public health and that there is an urgent need for their surveillance and the adoption of control measures, especially in the state of Paraná.

Phylogeny and Virulence Factors of Escherichia coli Isolated from Dogs with Pyometra.

We aimed to investigate the occurrence, phylogeny, and virulence of E. coli in the uterine contents and urine of female dogs with pyometra, through the presence of virulence genes and their genetic similarity. Uterine secretions and urine samples from 52 female dogs with pyometra were collected and cultured. Strains identified as E. coli from 25 uterine and 7 urine samples were tested for virulence genes by PCR. Genetic similarity between the isolates was studied using RAPD-PCR. E. coli was observed in 48.07% uterine samples with pyometra and 20.0% urine samples. The strains showed high percentages for the presence of virulence genes: 96.9% had the gene sfa, 59.4% afa, 46.9% pap, 53.1% hly, and 68.75% cnf. Even with the high prevalence of virulence genes, the samples were not submitted to DNA sequencing to confirm the results. Analysis showed high genetic diversity in E. coli, however, strains isolated from the same animal indicate that cystitis and pyometra could be related. Our study indicated the association between E. coli in dogs with pyometra and cases of urinary tract infection and the pathogenic potential of strains increasing with animal age.

A Ternary Copper (II) Complex with 4-Fluorophenoxyacetic Acid Hydrazide in Combination with Antibiotics Exhibits Positive Synergistic Effect against Salmonella Typhimurium.

Salmonella spp. continues to figure prominently in world epidemiological registries as one of the leading causes of bacterial foodborne disease. We characterised 43 Brazilian lineages of Salmonella Typhimurium (ST) strains, characterized drug resistance patterns, tested copper (II) complex as control options, and proposed effective antimicrobial measures. The minimum inhibitory concentration was evaluated for seven antimicrobials, isolated and combined with the copper (II) complex [Cu(4-FH)(phen)(ClO4)2] (4-FH = 4-fluorophenoxyacetic acid hydrazide and phen = 1,10-phenanthroline), known as DRI-12, in planktonic and sessile ST. In parallel, 42 resistance genes were screened (PCR/microarray). All strains were multidrug resistant (MDR). Resistance to carbapenems and polymyxins (86 and 88%, respectively) have drawn attention to the emergence of the problem in Brazil, and resistance is observed also to CIP and CFT (42 and 67%, respectively), the drugs of choice in treatment. Resistance to beta-lactams was associated with the genes blaTEM/blaCTX-M in 39% of the strains. Lower concentrations of DRI-12 (62.7 mg/L, or 100 µM) controlled planktonic and sessile ST in relation to AMP/SUL/TET and AMP/SUL/TET/COL, respectively. The synergistic effect provided by DRI-12 was significant for COL/CFT and COL/AMP in planktonic and sessile ST, respectively, and represents promising alternatives for the control of MDR ST.

Tongue nodules in an atypical canine leishmaniasis in Brazil.

We aimed to report a case of canine leishmaniasis with the only visible clinical sign being the presence of nodules in the lateral region of the tongue. The bitch was treated for a mandibular fracture, when multiple small nodules were observed on the tongue. We identify nodular glossitis with the presence of structures compatible with amastigote forms of Leishmania. The bitch was positive by ELISA, RIFI and PCR assays. Clinical re-evaluation after one year of treatment for leishmaniasis showed clinical improvement, but there was maintenance of antibody titers and infectivity. Lingual nodules as the only clinical sign of the disease is rare, especially in endemic areas, but should be included as differential diagnosis for leishmaniasis in the country.

Molecular Characterization and Survive Abilities of Salmonella Heidelberg Strains of Poultry Origin in Brazil.

The aim of the study was to evaluate the genotypic and phenotypic characteristics of 20 strains of S. Heidelberg (SH) isolated from broilers produced in southern Brazil. The similarity and presence of genetic determinants linked to virulence, antimicrobial resistance, biofilm formation, and in silico-predicted metabolic interactions revealed this serovar as a threat to public health. The presence of the ompC, invA, sodC, avrA, lpfA, and agfA genes was detected in 100% of the strains and the luxS gene in 70% of them. None of the strains carries the bla SHV, mcr-1, qnrA, qnrB, and qnrS genes. All strains showed a multidrug-resistant profile to at least three non-ß-lactam drugs, which include colistin, sulfamethoxazole, and tetracycline. Resistance to penicillin, ceftriaxone (90%), meropenem (25%), and cefoxitin (25%) were associated with the presence of bla CTX-M and bla CMY-2 genes. Biofilm formation reached a mature stage at 25 and 37°C, especially with chicken juice (CJ) addition. The sodium hypochlorite 1% was the least efficient in controlling the sessile cells. Genomic analysis of two strains identified more than 100 virulence genes and the presence of resistance to 24 classes of antibiotics correlated to phenotypic tests. Protein-protein interaction (PPI) prediction shows two metabolic pathways correlation with biofilm formation. Virulence, resistance, and biofilm determinants must be constant monitoring in SH, due to the possibility of occurring infections extremely difficult to cure and due risk of the maintenance of the bacterium in production environments.

Salmonella enterica Serovar Minnesota Biofilms, Susceptibility to Biocides, and Molecular Characterization.

The presence of virulence genes, phylogenetic relationships, biofilm formation index (BFI), and ultrastructure in S. Minnesota at different temperatures (4, 25, and 36 °C) were analyzed. In addition, the ability of biocidal agents (chlorhexidine1%, sodium hypochlorite 1%, and peracetic acid 0.8%) to inhibit biofilms formed by 20 strains isolated from broiler slaughter plants from two Brazilian companies in 2009, 2010, and 2014 was determined. The presence of specific genes was evaluated by PCR and phylogeny between strains by pulsed-field gel electrophoresis. The BFI was determined using tryptone soy broth with 5% of chicken juice, and its structure was observed by scanning electron microscopy. The presence of specific genes indicated that S. Minnesota has the potential to cause disease in humans, adapting to adverse conditions. Temperatures of 25 and 36 °C favored biofilm formation, although at 4 °C, there was still biomass that could contaminate the final product. Tolerance to all biocides was identified in 12/20 (60%), representing a real risk of adaptation mechanisms development, especially regarding to resistance to sodium hypochlorite. Phylogenetic analysis indicated cross-contamination and spread among companies, which was probably related to biofilms formation. Results show the necessity of attention to this serovar considering its resistance to sodium hypochlorite, including the need for rigorous control, adopting low temperatures to prevent biofilms formation in the poultry industry.

Genotypical Relationship Between Human and Poultry Strains of Campylobacter jejuni.

This study aimed to compare the genotype diversity of C. jejuni isolates. From the total of 64 C. jejuni strains evaluated, 44 were isolated from broiler carcasses (2015-2016) and 20 from hospitalized patients with gastroenteritis caused by the microorganism (2000-2006). The strains were correlated for the presence of flaA, pldA, cadF, ciaB, cdtABC, luxS, dnaJ, cbrA, htrA, pVir, Hcp, cstII, and neuA genes by PCR (polymerase chain reaction) and for phylogenetic proximity by PFGE (pulsed-field gel electrophoresis). Of the total strains studied, 28 (43.7%) presented all the studied genes, except pVir. Among these strains, 25 (89.3%) were of poultry origin. Poultry strains showed a higher prevalence (P < 0.05) of genes linked to adhesion, colonization, invasion, cytotoxicity, biofilm formation, and adaptation to adverse conditions. Additionally, the profile that denotes the presence of all genes identified in the study (P1) was identified in 56.8% of poultry strains and in 15.0% of human strains. Molecular typing analysis identified five pulsotypes, none of which grouped strains from different origins. Although human strains were from hospitalized patients, they presented limited virulence capacity and adaptability to adverse conditions compared to chicken carcasses, besides being different in molecular typing. However, the ability to cause Guillain-Barré Syndrome is equal for both strains. In general, poultry strains, being more recent, are more specialized to adapt to the environment, invade, and cause disease in the human host.

Antibiotic Resistance in the Alternative Lifestyles of Campylobacter jejuni.

Campylobacter jejuni is the main pathogen identified in cases of foodborne gastroenteritis worldwide. Its importance in poultry production and public health is highlighted due to the growing antimicrobial resistance. Our study comparatively investigated the effect of five different classes of antimicrobials on the planktonic and biofilm forms of 35 strains of C. jejuni with high phylogenetic distinction in 30 of them. In the planktonic form, the existence of susceptible strains to colistin (7/35 - 20%) and resistance to meropenem (3/35 - 8.6%) represent a novelty in strains evaluated in Brazil. In biofilms formed with the addition of chicken juice, the number of resistant strains was significantly higher for colistin, erythromycin and meropenem (100%), but the susceptibility to tetracycline was shown as a control strategy for specific cases. High concentrations (1,060 ± 172.1mg/L) of antibiotics were necessary to control the biofilm structure in susceptible strains in the planktonic form, which is consistent with the high biomass produced in these strains. Stainless steel and polyurethane were the most (BFI=2.1) and least (BFI=1.6) favorable surfaces for the production of biomass treated with antimicrobials. It is concluded that the antimicrobial action was detected for all tested drugs in planktonic form. In sessile forms, the biomass production was intensified, except for tetracycline, which showed an antibiofilm effect.

The perception of octave pitch affinity and harmonic fusion have a common origin.

Musicians say that the pitches of tones with a frequency ratio of 2:1 (one octave) have a distinctive affinity, even if the tones do not have common spectral components. It has been suggested, however, that this affinity judgment has no biological basis and originates instead from an acculturation process ‒ the learning of musical rules unrelated to auditory physiology. We measured, in young amateur musicians, the perceptual detectability of octave mistunings for tones presented alternately (melodic condition) or simultaneously (harmonic condition). In the melodic condition, mistuning was detectable only by means of explicit pitch comparisons. In the harmonic condition, listeners could use a different and more efficient perceptual cue: in the absence of mistuning, the tones fused into a single sound percept; mistunings decreased fusion. Performance was globally better in the harmonic condition, in line with the hypothesis that listeners used a fusion cue in this condition; this hypothesis was also supported by results showing that an illusory simultaneity of the tones was much less advantageous than a real simultaneity. In the two conditions, mistuning detection was generally better for octave compressions than for octave stretchings. This asymmetry varied across listeners, but crucially the listener-specific asymmetries observed in the two conditions were highly correlated. Thus, the perception of the melodic octave appeared to be closely linked to the phenomenon of harmonic fusion. As harmonic fusion is thought to be determined by biological factors rather than factors related to musical culture or training, we argue that octave pitch affinity also has, at least in part, a biological basis.

Hybrid Pectin-Liposome Formulation against Multi-Resistant Bacterial Strains.

This work describes the development of a gastroresistant antimicrobial formulation composed of two carriers, pectin and liposomes, intended to improve the efficiency of norfloxacin (NOR) against multi-resistant bacterial strains. The formulations showed physicochemical stability for 180 days (4 °C) in terms of size, polydispersity, and zeta potential of the vesicles, prolonging the in vitro release of NOR for 11 h. The hybrid nanocarriers improved the in vitro antimicrobial activity against different multidrug-resistant bacterial strains, such as Salmonella sp., Pseudomonasaeruginosa, E. coli and Campylobacterjejuni, in comparison to commercial NOR and liposomal suspensions. The in vivo toxicity assay in chicken embryos revealed that the hybrid systems were not toxic in any of the different parameters analyzed, a result also corroborated by the analyses of biochemical biomarkers of the chicken-embryos liver function.

Consumption of minas frescal cheese may be a source of human infection by Campylobacter jejuni / Consumo de queijo minas frescal pode ser fonte de infecção humana por Campylobacter jejuni

Campylobacter spp. is an emerging pathogen that causes gastroenteritis in humans and the consumption of dairy food can characterize sources of infection. We aimed to verify the viability and a presence of transcripts associated with characteristics of virulence and adaptation of C. jejuni isolated from Minas Frescal cheeses, produced with contaminated milk and stored under refrigeration for up to ten days. The samples were analyzed for bioindicators, Campylobacter spp., pH, acidity, moisture and sodium chloride. Campylobacter spp. recovered were evaluated for the production of transcripts of: ciaB, dnaJ, p19 and sodB. The results were correlated with the viability of C. jejuni and changes in their transcriptome. Storage at lowtemperatures reduced C. jejuni from the first to the fourth day. The variations in humidity, pH and acidity influenced the decreasing of C. jejuni. There was a reduction in transcripts' production of the four genes, more pronounced on the fourth day, indicating the inability of the microorganism to perform its metabolic activities, due to the conditions of injury. Despite the presence of mechanisms of virulence and adaptation, C. jejuni could not remain viable four days after production. However, consumption of fresh cheese contaminated with Campylobacter jejuni can be a source of infection when consumed up to four days after production.

Campylobacter spp. é um patógeno emergente que causa gastroenterite em seres humanos e o consumo de produtos lácteos pode caracterizar fontes de infecção. O objetivo deste estudo foi verificar a viabilidade e a presença de transcritos associadas a características de virulência e adaptação de C. jejuniisoladas de queijos frescos, produzidos com leite contaminado e mantidos refrigeradas por dez dias. Foram analisados bioindicadores, Campylobacter spp., pH, acidez, umidade e cloreto de sódio. Campylobacter spp. recuperados foram avaliados quanto à produção dos transcritos: ciaB, dnaJ, p19 e sodB. Os resultados foram correlacionados com a viabilidade de C. jejuni e alterações no transcriptoma. O armazenamento em baixas temperaturas reduziu C. jejuni do primeiro ao quarto dia. As variações na umidade, pH e acidez influenciaram a queda de C. jejuni. Houve uma redução na produção de transcritos dos quatro genes, mais pronunciada no quarto dia, indicando a incapacidade do micro-organismo em realizar suas atividades metabólicas, devido às condições de injúria. Apesar da presença de mecanismos de virulência e adaptação, C. jejuni não permaneceu viável quatro dias após a produção. Porém, o consumo de queijo fresco contaminado com Campylobacter jejunipode ser uma fonte de infecção quando consumido até quatro dias após a produção.

Characteristics of virulence, resistance and genetic diversity of strains of Salmonella Infantis isolated from broiler chicken in Brazil / Características de virulência, resistência e diversidade genética de estirpes de Salmonella Infantis isoladas de frangos de corte no Brasil

Salmonella Infantis is frequently associated with human infections worldwide and is transmitted by consumption of contaminated foods, particularly those of animal origin, especially the chicken meat. We aimed to evaluate virulence characteristics, antimicrobial resistance and the genetic similarity of 51 strains of S. Infantis isolated from samples of poultry origin. The strains were isolated from 2009 to 2010 in a company with full cycle of broiler's production in the state of São Paulo, Brazil. The antimicrobial susceptibility test was performed and, by PCR, we evaluated the presence of the genes lpfA (hem-adhesion), agfA (hem-biofilm) and sefA (hem-adhesion) and resistance genes to beta-lactams (blaTEM, blaSHV, bla CTX-M and blaAmpC ). The phylogenetic relationship was determined by RAPD-PCR method. Among the drugs tested, the highest percentages of resistance were to amoxicillin (35.3%) and to sulfonamide (15.7%). Eleven antimicrobial resistance patterns were identified (A1 to A11), none of them presented a multiresistance profile (> 3 antimicrobials classes). There was 100% of positivity for the agfA gene, 92.2% for the lpfA gene, and no strain presented the sefA gene. Most of the isolates showed similarities in virulence potential, since they were simultaneously positive for two studied genes, agfA and lpfA (92.2%, 47/51). Of the 18 (35.3%) strains resistant to antimicrobials of the β-lactam class, 10 (55.5%) were positive to blaAmpC gene, five (27.8%) for blaCTX-M , two (11.1%) to blaSHV and no strain presented the blaTEM gene. The phylogenetic evaluation has shown the presence of five clusters (A, B, C, D and E) with similarity greatSalmonella Infantis is frequently associated with human infections worldwide and is transmitted by consumption of contaminated foods, particularly those of animal origin, especially the chicken meat. We aimed to evaluate virulence characteristics, antimicrobial resistance and the genetic similarity of 51 strains of S. Infantis isolated from samples of poultry origin. The strains were isolated from 2009 to 2010 in a company with full cycle of broiler's production in the state of São Paulo, Brazil. The antimicrobial susceptibility test was performed and, by PCR, we evaluated the presence of the genes lpfA (hem-adhesion), agfA (hem-biofilm) and sefA (hem-adhesion) and resistance genes to beta-lactams (blaTEM, blaSHV, bla CTX-M and blaAmpC ). The phylogenetic relationship was determined by RAPD-PCR method. Among the drugs tested, the highest percentages of resistance were to amoxicillin (35.3%) and to sulfonamide (15.7%). Eleven antimicrobial resistance patterns were identified (A1 to A11), none of them presented a multiresistance profile (> 3 antimicrobials classes). There was 100% of positivity for the agfA gene, 92.2% for the lpfA gene, and no strain presented the sefA gene. Most of the isolates showed similarities in virulence potential, since they were simultaneously positive for two studied genes, agfA and lpfA (92.2%, 47/51). Of the 18 (35.3%) strains resistant to antimicrobials of the ß-lactam class, 10 (55.5%) were positive to blaAmpC gene, five (27.8%) for blaCTX-M , two (11.1%) to blaSHV and no strain presented the blaTEM gene. The phylogenetic evaluation has shown the presence of five clusters (A, B, C, D and E) with similarity greater than 80%, and three distinct strains which were not grouped in any cluster. Cluster B grouped 33 strains, all positive for lpfA and agfA genes, from both, the broiler farming facility and the slaughterhouse, persistent throughout all the study period. This cluster also grouped 18 strains clones with genetic similarity greater than 99%, all isolated in the slaughterhouse. The presence of virulence genes associated with persistent strains clones for a long period, warns to the possibility of S. Infantis to form biofilm, and should be constantly monitored in broilers' production chain, in order to know the profile of the strains that may contaminate the final product and evaluate the hazards that represents to public health.er than 80%, and three distinct strains which were not grouped in any cluster. Cluster B grouped 33 strains, all positive for lpfA and agfA genes, from both, the broiler farming facility and the slaughterhouse, persistent throughout all the study period. This cluster also grouped 18 strains clones with genetic similarity greater than 99%, all isolated in the slaughterhouse. The presence of virulence genes associated with persistent strains clones for a long period, warns to the possibility of S. Infantis to form biofilm, and should be constantly monitored in broilers' production chain, in order to know the profile of the strains that may contaminate the final product and evaluate the hazards that represents to public health.(AU)

Salmonella Infantis é frequentemente associada a infecções humanas no mundo todo sendo transmitida pelo consumo de alimentos contaminados, principalmente aqueles de origem animal, com destaque para a carne de frango. Objetivou-se avaliar características de virulência, resistência antimicrobiana e a similaridade genética de 51 estirpes de S. Infantis isoladas em amostras de origem avícola. As estirpes foram isoladas no período de 2009 a 2010 em uma empresa com ciclo completo de produção de frango de corte, localizada no estado de São Paulo, Brasil. Foi realizado o teste de susceptibilidade antimicrobiana e pela técnica de PCR, foi avaliada a presença dos genes lpfA (fímbria-adesão), agfA (fímbria-biofilme) e sefA (fímbria-adesão) e os genes de resistência aos beta-lactâmicos (bla TEM, blaSHV, blaCTX-M e blaAmpC ). A relação filogenética foi determinada pelo método de RAPD-PCR. Dentre as drogas testadas, os maiores percentuais de resistência foram para amoxacilina com 35,3% e sulfonamida com 15,7%. Onze perfis de resistência aos antimicrobianos foram identificados (A1 a A11), sendo que nenhum deles apresentou perfil de multirresistência (>3 classes de antimicrobianos). Houve 100% de positividade para o gene agfA, 92,2% para o gene lpfA e nenhuma estirpe apresentou o gene sefA. A maioria dos isolados apresentaram semelhanças no potencial de virulência, pois foram positivos simultaneamente para dois genes estudados, agfA e lpfA (92,2% - 47/51). Das 18 (35,3%) estirpes resistentes aos antimicrobianos da classe dos ß-lactâmicos, 10 (55,5%) foram positivas para o gene blaAmpC , cinco (27,8%) para blaCTX-M , duas (11,1%) para blaSHV e nenhuma estirpe apresentou o gene bla TEM . A avaliação filogenética demonstrou a presença de cinco clusters (A, B, C, D e E) com similaridade superior a 80%, e três estirpes distintas que não foram agrupadas em nenhum dos clusters. O cluster B agrupou 33 estirpes, todas positivas para os genes lpfA e agfA, provenientes tanto do aviário quanto do matadouro frigorífico, persistentes durante todo o período do estudo. Este cluster ainda agrupou 18 estirpes clones com similaridade genética superior a 99%, todas isoladas no matadouro frigorífico. A presença dos genes de virulência, associada à persistência das estirpes clones durante um longo período do estudo, alertam para a possibilidade de S. Infantis em formar biofilme, devendo ser constantemente monitorada na cadeia de produção avícola, especialmente no ambiente de abate, de forma a conhecer o perfil das estirpes que podem contaminar o produto final e assim avaliar os perigos que representam para a saúde pública.(AU)

Nanocarriers From Natural Lipids With In Vitro Activity Against Campylobacter jejuni.

Campylobacter jejuni (CJ) is the most prevalent zoonotic pathogen of chicken meat and related products, which may lead to gastroenteritis and autoimmune diseases in humans. Although controlling this bacterium is important, CJ strains resistance against traditional antibiotic therapy has been increased. Vegetable oils and fats are natural biomaterials explored since the Ancient times, due to their therapeutic properties. Nanotechnology has promoted the miniaturization of materials, improving bioavailability and efficacy, while reducing the toxicity of loaded active molecules. In this work, a screening of 28 vegetable oils was firstly performed, in order to select anti-CJ candidates by the disc diffusion test. Thus, the selected liquid lipids were used as active molecules in nanostructured lipid carriers (NLC) formulations. The three resultant systems were characterized in terms of particle size (~200 nm), polydispersity index (~0.15), and zeta potential (~-35mV), and its physicochemical stability was confirmed for a year, at 25°C. The structural properties of NLC were assessed by infrared (FTIR-ATR) and differential scanning calorimetry (DSC) analyses. The spherical nanoparticle morphology and narrow size distribution was observed by transmission electron microscopy (TEM) and field emission scanning electron (FE-SEM) analyses, respectively. Then, the in vitro antimicrobial activity test determined the minimum inhibitory concentration (MIC) of each formulation against CJ strains, in both free (1-3 mg/ml-1) and sessile (0.78 mg/ml-1) forms. Finally, the in vitro biocompatibility of NLC was demonstrated through cell viability using VERO cell line, in which F6 was found twice less cytotoxic than pure olibanum oil. Considering the abovementioned achieved, F6 formulation is able to be evaluated in the in vivo anti-CJ efficacy assays.

Viability and gene transcription of Campylobacter jejuni in infant milk formulas / Viabilidade e transcrição genética de Campylobacter jejuni em fórmulas lácteas infantis

This study simulated the contamination of two varieties of infant milk formulas (homemade and commercial) with 103 and 104 CFU/mLof Campylobacter jejuni, that were kept under refrigeration (4-7ºC) for up to 48 hours. The aim of this study was to verify the maintenance of the viability and ability of Campylobacter jejuni to produce transcripts of virulence and resistance to stress conditions during periods of 0 (after preparation), 24 and 48 hours. C. jejuni remained viable during all analyzed stages and thepresence of coliforms was not detected. In general, the counts reduced 1 log cycle after 48 hours for all samples, except the 104 CFU/mL inoculum of commercial formula, which reduced 2 log cycles, indicating greater injury of C. jejuni in this food matrix. C. jejuni showed to be more adapted to homemade matrix, due to high transcription of the gene related to cell invasion, ciaB, and more susceptible in the commercial matrix, due to the high transcription of genes related to conditions of stress tolerance (dnaJ, p19, sodB). The low infective dose of C. jejuni coupled with greater vulnerability of children less than five years indicate the need for care in the preparation and maintenance of infant formulas, to prevent the use of contaminated raw material and cross-contamination, especially in homemade formulations

Este estudo simulou a contaminação de duas variedades de fórmulas de leite infantil com Campylobacter jejuni (caseiras e comerciais), que foram mantidas sob refrigeração (4-7ºC) por até 48 horas. O objetivo do estudo foi verificar a manutenção da viabilidade e capacidade de produzir transcritos de virulência e resistência a condições de estresse durante os períodos de 0 (após preparação), 24 e 48 horas. C. jejunipermaneceu viável durante todas as etapas analisadas e a presença de coliformes não foi detectada. Em geral, as contagens reduziram 1 ciclo log após 48 horas para todas as amostras, exceto o inóculo de 104 CFU/mL na fórmula comercial, que reduziu 2 ciclos logarítmicos, indicando maior lesão de C. jejuni nesta matriz alimentar. C. jejuni mostrou-se mais adaptado à matriz popular, devido à alta transcrição do gene relacionado à invasão celular, ciaB, e mais suscetível na matriz comercial, devido à alta transcrição de genes relacionados a tolerância a condições de estresse (dnaJ, p19, sodB). A baixa dose infectante de C. jejuni, juntamente com maior vulnerabilidade de crianças menores de cinco anos, indicam a necessidade de cuidados na preparação e manutenção de fórmulas infantis, para prevenir o uso de matéria-prima contaminada e contaminação cruzada, especialmente em formulações caseiras.

Campylobacter jejuni and Campylobacter coli originated from chicken carcasses modulate their transcriptome to translate virulence genes in human cells / Campylobacter jejuni e Campylobacter coli originadas de carcaças de frango modulam seu transcriptoma para traduzir genes de virulência em células humanas

The aim was to determine the spread of genetically similar profiles of Campylobacter in chicken carcasses and evaluate their ability to produce transcripts for ciaB, dnaJ, p19 and sodB genes, before and after cultivation in Caco-2 cells. The strains used were isolated from 420 samples of chicken carcasses chilled and frozen ready for marketing. The species were identified by PCR-multiplex, the phylogeny was determined by RAPD-PCR and the presence of transcripts was performed by RT-PCR. We identified 74 (17.6%) of Campylobacter strains, being 55 (74.3%) C. jejuni and 19 (25.7%) C. coli. The phylogenetic relationship demonstrated heterogeneity between isolates of the same species, with absence of clones, indicating the high level of diversity of circulating genotypes. The gene transcription showed conflicting results before and after the culture in Caco-2 cell, so that before cultivation isolates showed greater capacity to transcribe genes related to survival and after the interaction with human cells, the strains showed higher potential to transcribe genes associated with virulence. The result of this study contributes to the understanding of how these seemingly fragile microorganisms are the most prevalent bacterial agents in human gastroenteritis.(AU)

O objetivo foi determinar a disseminação de perfis geneticamente semelhantes de Campylobacter em carcaças de frango e avaliar sua capacidade de produzir transcritos para os genes ciaB, dnaJ, p19 e sodB, antes e após o cultivo em células Caco-2. As cepas utilizadas foram isoladas de 420 amostras de carcaças de frango resfriadas e congeladas prontas para comercialização. As espécies foram identificadas por PCR-multiplex, a filogenia foi determinada por RAPD-PCR e a presença de transcritos foi realizada por RT-PCR. Identificamos 74 (17,6%) das cepas de Campylobacter, sendo 55 (74,3%) C. jejuni e 19 (25,7%) C. coli. A relação filogenética demonstrou heterogeneidade entre isolados da mesma espécie, com ausência de clones, indicando o alto nível de diversidade dos genótipos circulantes. A transcrição gênica mostrou resultados conflitantes antes e após a cultura em células Caco-2, de modo que, antes do cultivo, os isolados apresentaram maior capacidade de transcrever genes relacionados à sobrevivência e após a interação com células humanas, as linhagens apresentaram maior potencial para transcrever genes associados à virulência. O resultado deste estudo contribui para a compreensão de como esses microrganismos aparentemente frágeis são os agentes bacterianos mais prevalentes na gastroenterite humana.(AU)

Ação de diferentes sanitizantes em biofilmes de Salmonella Minnesota / Action of different sanitizers in biofilmes of Salmonella Minnesota

Objetivou-se avaliar a eficiência do contato por 15 minutos do hipoclorito de sódio 1%, e ácido peracético 0,8% na inibição de biofilmes formad os por três cepas distintas de Salmonella Minnesota em aço, poliuretano e polipropileno e determinar a recuperação das células remanescentes. Qualitativamente houve influência na classificação dos biofilmes de acordo com a superfície, que foram diferentes dependendo do tipo de cepa e de material, porém a quantidade de células sésseis permanece constante, pois independente da cepa e da superfície, os biofilmes mantiveram uma contagem de 5,18 Log UFC, indicando que as diferenças referem-se à matriz polimérica. O uso do hipoclorito foi capaz de destruir as células, que não foram recuperadas após reincubação. Já o ácido peracético não promoveu redução significativa. O uso do hipoclorito de sódio 1% é eficiente na sua remoção.

Resistência aos antimicrobianos de Salmonella heidelberg isoladas na cadeia de produção avícola / Antimicrobial resistance of Salmonella heidelberg isolated in the poultry chain production

S. Heidelberg é responsável por causar doença grave em humanos, e por apresentar alta resistência aos antimicrobianos, sendo considerada um problema emergente na saúde pública mundial. Objetivou-se determinar a resistência aos antimicrobianos em 67 cepas de S. Heidelberg isoladas na cadeia de produção avícola no ano de 2016. Utilizou-se a técnica de disco difusão frente ao ácido nalidíxico, amoxacilina/ácido clavulânico, ceftazidima, ceftiofur, ciprofloxacina, enrofloxacina, gentamicina, imipenem, sulfametoxazol/trimetoprim, sulfato de colistina, tetraciclina. Os maiores índices de resistência foram para o ácido nalidíxico e tetraciclina (100%), seguido do sulfato de colistina (98,5%).Todas as cepas foram classificadas como multirresistentes, alarmando para o perigo que representam para a saúde pública.

Spread of the serotypes and antimicrobial resistance in strains of Salmonella spp. isolated from broiler.

Serotypes and antimicrobial susceptibility of Salmonella's isolates from broiler production chain were determined. A total of 239 isolated strains from chicken, carcasses, breeding environments, and slaughter was analyzed by disk diffusion test, in the period of 2009 to 2010. For antibiotics with a high number of resistant strains, the minimal inhibitory concentration (MIC) was performed. We identified 24 serotypes, being the most frequent, Minnesota (31.4%) and Infantis (22.6%). The highest percentages of resistance were obtained for sulfonamide (42.7%), followed by tetracycline with 37.6% and amoxicillin with 27.6%. From the total, 32 resistance profiles were identified, being 60.7% of the strains were resistant to at least one antibiotic. Of these, 31.7% of the isolates showed multidrug resistance profiles belonging to serovar Minnesota, Saintpaul, and S. enterica. The highest resistance was found in isolates from slaughterhouse (66.9%) and aviary (58.7%). A large number of strains showed MIC above the maximum tested concentration for the antibiotics amoxicillin and sulfamethoxazole. The high number of Salmonella's resistant strains indicates the need for prudent use of these drugs in poultry production in order to reduce the occurrence and spread of antibiotic resistance profiles, and the risk that multiresistant strains isolated from broilers may pose a risk to human health.

Evolution of Campylobacter jejuni of poultry origin in Brazil.

Campylobacter jejuni is the most common pathogen associated with foodborne diseases. Persistent presence of this pathogen contaminating the environment in slaughterhouses and chicken products have been reported worldwide. Although many efforts have been employed for reducing C. jejuni contamination, few studies have been conducted to understand the dynamics of C. jejuni in slaughterhouses over time. In this study, we evaluated the virulence, antibiotic resistance and genetic diversity profiles of 99 C. jejuni isolated from chilled chicken carcasses collected in Brazilian slaughterhouses during two distinct periods (2011-2012 and 2015-2016). The virulence profile was evaluated for the presence of flaA, ciaB, cadF, pldA and cdtABC genes. Antibiotic resistance was evaluated for amoxicillin-clavulanic acid, gentamicin, erythromycin and tetracycline. Genetic diversity was assessed using RAPD-PCR. The prevalence of C. jejuni was significantly reduced in 2015-2016 as well the number of antibiotic (and multidrug) resistant isolates, except for tetracycline. However, isolates from 2015 to 2016 showed higher prevalence of multiple virulence genes and genetic diversity profile compared to isolates from 2011 to 2012. During the studied period, stricter regulations to control pathogens in poultry farms and slaughterhouses were implemented in Brazil, which may have contributed to the profile variation observed due to changes of selective pressures on bacterial populations.