Pathogenic bacteria

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The Abundance of some Pathogenic Bacteria In Mangrove Habitats of Paraiba do Norte Estuary and Crabmeat Contamination of Mangrove Crab Ucides cordatus

The Abundance of some Pathogenic Bacteria In Mangrove Habitats of Paraiba do Norte Estuary and Crabmeat Contamination of Mangrove Crab Ucides cordatus

Since long the Paraíba do Norte river suffers from degradation caused by the non-treated domestic wastes, agriculture and industrial residues discharged to the mangrove area. The present work showed that the two mangrove sites along the Paraíba do Norte estuary being under different level of sewage influence, differed in physical, chemical and microbiological characteristics of the water and sediment. The sampling site CG, closer to the local of sewage effluent, showed higher incidence of total heterotrophic bacteria, coliforms, and pathogenic bacteria, such as Salmonella and S. aureus. The results obtained showed a decrease of contaminant microorganisms in the Paraíba do Norte river downstream the discharge point. Similarly, Al-Sayed et al. (2005) reported that the distribution of total and faecal coliforms in water showed a distinctive decreasing pattern downstream the Arabian Gulf mangrove sites.
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MICROBIAL LOAD AND MULTIPLE DRUG RESISTANCE OF PATHOGENIC BACTERIA ISOLATED FROM FEACES AND BODY SURFACES OF COCKROACHES IN AN URBAN AREA OF SOUTHWESTERN NIGERIA

MICROBIAL LOAD AND MULTIPLE DRUG RESISTANCE OF PATHOGENIC BACTERIA ISOLATED FROM FEACES AND BODY SURFACES OF COCKROACHES IN AN URBAN AREA OF SOUTHWESTERN NIGERIA

Antimicrobial resistance of pathogenic microorganisms has assumed a worrisome dimension with recent trend of resistance of pathogenic bacteria to common antibiotics. This increase in antibiotic resistance was premised on the drug pressure as a result of abuse of common antibiotics by the users and uncomplimentary fake drugs in circulation (Ehinmidu 2003, Tachebe et al., 2006, Oleghe et al., 2011). The unwholesome behaviour has led to the genetic response of the microorganisms to microbial therapy which has now become an issue mitigating the control of pathogenic microorganisms in different parts of the world (Oleghe et al., 2011).
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A reservoir of drug-resistant pathogenic bacteria in asymptomatic hosts.

A reservoir of drug-resistant pathogenic bacteria in asymptomatic hosts.

The population genetics of pathogenic bacteria has been intensively studied in order to understand the spread of disease and the evolution of virulence and drug resistance. However, much less attention has been paid to bacterial carriage populations, which inhabit hosts without producing disease. Since new virulent strains that cause disease can be recruited from the carriage population of bacteria, our understanding of infectious disease is seriously incomplete without knowledge on the population structure of pathogenic bacteria living in an asymptomatic host. We report the first extensive survey of the abundance and diversity of a human pathogen in asymptomatic animal hosts. We have found that asymptomatic swine from livestock productions frequently carry populations of Salmonella enterica with a broad range of drug-resistant strains and genetic diversity greatly exceeding that previously described. This study shows how agricultural practice and human intervention may lead and influence the evolution of a hidden reservoir of pathogens, with important implications for human health.
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Effect of Erica australis extract on Caco-2 cells, fibroblasts and selected pathogenic bacteria responsible for wound infection

Effect of Erica australis extract on Caco-2 cells, fibroblasts and selected pathogenic bacteria responsible for wound infection

Title: Effect of Erica australis extract on CACO-2 cells, fibroblasts and selected 1 .. pathogenic bacteria responsible for wound infection 2 .[r]

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The use of colorimetric sensor arrays to discriminate between pathogenic bacteria.

The use of colorimetric sensor arrays to discriminate between pathogenic bacteria.

In this report, we have demonstrated that our current- generation CSA has the necessary sensitivity and selectivity to identify both bacterial species and strain via headspace gas analysis, starting at very low inoculum concentrations of about 10 CFU/plate for several strains (Table 1). Feature extraction and LDA revealed that different strains within the same species have unique VOC patterns, independent of inoculum concentration. Although the results of this pilot study are very promising, there is considerable room to improve the technology for practical and reliable application. For example, the set of colorimetric indicators should be tuned to maximize sensitivity to the metabolic volatiles released by the species of interest; conversely, growth media could be optimized to match their VOC production to the classes of volatiles to which the CSAs are most sensitive. Replacing the open Petri dish with a smaller, sealed sample chamber could speed detection time by increasing metabolic volatile concentrations at the sensor. Finally, all of these results must be validated on a much larger and more diverse library of pathogenic and non-pathogenic bacteria. Further development of this technology could ultimately lead to a mobile handheld unit as small as a cell phone that would safely sample and incubate a hazardous pathogen, track its metabolic volatile production using a cheap and disposable sensor, and automatically match its species and strain to an onboard library of pre-recorded signatures.
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Antagonistic Activity of Antibiotic Producing Streptomyces sp. against Fish and Human Pathogenic Bacteria

Antagonistic Activity of Antibiotic Producing Streptomyces sp. against Fish and Human Pathogenic Bacteria

The antagonistic activity of soil isolates was evaluated by Cross Streak method (Rahman et al. 2011). Each of the isolate was streaked on Streptomyces Agar Medium (SAM) as straight line and incubated at 30°C for six days. Then the plates were seeded with test organisms by a single streak at a 90° angle to the Streptomyces isolates and incubated at 37 and 27°C for 24 h for human and fish pathogenic bacteria, respectively. The antagonistic effect of Streptomyces sp. isolates on test organism was analyzed by the determination of size of inhibition zone. The percentage of antagonism of Streptomyces isolates to each genus of test organisms was estimated.
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Location of pathogenic bacteria during persistent infections: insights from an analysis using game theory.

Location of pathogenic bacteria during persistent infections: insights from an analysis using game theory.

Bacterial persistent infections are responsible for a significant amount of the human morbidity and mortality. Unlike acute bacterial infections, it is very difficult to treat persistent bacterial infections (e.g. tuberculosis). Knowledge about the location of pathogenic bacteria during persistent infection will help to treat such conditions by designing novel drugs which can reach such locations. In this study, events of bacterial persistent infections were analyzed using game theory. A game was defined where the pathogen and the host are the two players with a conflict of interest. Criteria for the establishment of Nash equilibrium were calculated for this game. This theoretical model, which is very simple and heuristic, predicts that during persistent infections pathogenic bacteria stay in both intracellular and extracellular compartments of the host. The result of this study implies that a bacterium should be able to survive in both intracellular and extracellular compartments of the host in order to cause persistent infections. This explains why persistent infections are more often caused by intracellular pathogens like Mycobacterium and Salmonella. Moreover, this prediction is in consistence with the results of previous experimental studies.
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Pathogenic bacteria dissemination by ants (Hymenoptera: Formicidae) in two hospitals in northeast Brazil.

Pathogenic bacteria dissemination by ants (Hymenoptera: Formicidae) in two hospitals in northeast Brazil.

ABSTRACT - Nosocomial infections bring a high risk to the health of hospital patients and employees. Ants are common organisms in Brazilian hospitals, where they can act as dispersers of opportunistic microorganisms in places they forage. The occurrence of multi-resistant bacteria carried by ants was analyzed in two public hospitals (HA and HB) in southeastern Bahia, Brazil. In these two hospitals 132 workers belonging to three ant species were collected. The bacteria associated to these ants were identifi ed and their susceptibility to antibiotics was evaluated. More than half (57.3%) of ants collected in HA were associated with some kind of bacteria, with 26.7% of them being opportunist bacteria, while 84,2% of the ants from HB presented associated bacteria growth, with 61.4% of them being opportunist bacteria. Twenty four species of bacteria were isolated. The Gram-positive bacilli of the genus Bacillus were the most frequent, followed by the Gram-positive cocci, Gram-negative bacilli (family Enterobacteriaceae) and Gram-negative non-fermenters bacilli. The profi le of sensitivity of the bacterial isolates to drugs pointed out the existence of multi-resistant isolates carried by ants. For the fi rst time, are reported cases of the same bacterial resistant isolates taken form homospecifi c ant workers that point out the importance of ants to bacteria dissemination and proliferation in a hospital. Our results suggest that the risk of contamination presented by these ants is similar to the one of any other mechanical vector of bacterial dissemination.
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GAMMA IRRADIATION IN THE CONTROL OF PATHOGENIC BACTERIA IN REFRIGERATED GROUND CHICKEN MEAT

GAMMA IRRADIATION IN THE CONTROL OF PATHOGENIC BACTERIA IN REFRIGERATED GROUND CHICKEN MEAT

coli (Figure 3), what placed these samples within the microbiological limits established by the Brazilian legislation. Besides, these bacteria are mesophilic pathogens that do not usually grow in temperature of refrigeration, therefore, even if presenting few viable CFU, the infected product (presence of the pathogen) would not become infectant (pathogen in number to cause the disease) because these bacteria have to reach counts of 10 6 CFU g -1 to cause alimentary toxinfection.

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Vaccines based on the cell surface carbohydrates of pathogenic bacteria

Vaccines based on the cell surface carbohydrates of pathogenic bacteria

Glycoconjugate vaccines against meningococcal Group C and against seven pneumococcal serotypes have been licensed, whilst glycoconjugate vaccines against other meningococcal CPSs, more p[r]

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Phenotypic and genotypic characteristics of enterocin producing enterococci against pathogenic bacteria

Phenotypic and genotypic characteristics of enterocin producing enterococci against pathogenic bacteria

Enterocin EJ97 belongs to enterocins synthesized without a leader peptide that is active against Gram-positive bacteria as well as enterococci, several species of Bacillus, Listeria and strains of S.aureus (36). Even though both strains (E. hirae -36 and E. hirae-52) posses the same structural gene EJ97, E. hirae-36 had a larger zone of inhibition. This could be explained by two possible hypotheses: the antimicrobial activity was reinforced by the presence of enterocin P and enterocin A or eventual presence of “silent” gene(s) in E. hirae-52. Various authors report the presence of bacteriocin silent genes in enterococci (26, 37, 38).
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Modelling Antagonic Effect of Lactic Acid Bacteria Supernatants on Some Pathogenic Bacteria

Modelling Antagonic Effect of Lactic Acid Bacteria Supernatants on Some Pathogenic Bacteria

The objective of this work was to use a parametric and nonparametric statistical model of survival analysis to evaluate the bioprotective action of lactic acid bacteria sterile supernatants. Three independent pathogenic cultures (Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus) were treated with neutralized and non- neutralized filtered supernatants broth from cultures of Lactobacillus acidophilus, Lactobacillus rhamnosus, and Lactobacillus sake grown in MRS broth (Rogosa and Sharpe, 1961), in order to determine the most effective starter to be used in fresh sausage production.
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Pathogenic bacteria in turkey meat: A review

Pathogenic bacteria in turkey meat: A review

This bacterium can multiply inside host’s cells and is one of the most pathogenic microorganisms involved in FD outbreaks with a lethality of 20-30 % (ADDIS & SISAY, 2015). On around 19% of the death occurred in Europe at 2015 were attributed to poultry and the majority of death linked with poultry were caused by Listeria or Salmonella spp. (EFSA, 2016). The consequences are worse for children, seniors and immunocompromised (BEHRAVESH, 2012). Besides its virulence, listeriosis incidence has decreasing in the last three decades, with an occurrence of only 15 outbreaks registered from 1980 to 2000 in EU. Turkey meat was linked only to two of them (GOTTLIEB et al., 2006; OLSEN et al, 2005). Other two outbreaks were registered by USDA at 2000 and 2001 involving turkey meat (FRYE et al., 2002; CDC, 2002).
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The Relevance of Ribonuclease III in Pathogenic Bacteria

The Relevance of Ribonuclease III in Pathogenic Bacteria

role of RNase E was not found, leaving no clue for the process of B. subtilis RNA degradation. One answer came from the discovery of two different ribonucleases, the paralogous RNase J1 and J2, which are present in almost all bacteria lacking RNase E (Even et al., 2005). Curiously, both RNase E and RNase J1 orthologs have been found in Sinorhizobium meliloti (Madhugiri and Evguenieva-Hackenberg, 2009). Although there is no sequence homology, the RNase J enzymes share a similar architecture with RNase E (Li de la Sierra-Gallay et al., 2008) and exhibit equivalent endonucleolytic activity. RNase J1, which is essential for cell viability, is involved in RNA turnover (Mader et al., 2008) (Figure 1B). Surprisingly, this enzyme is also able to catalyse the exonucleolytic degradation of RNA in the 5’-3’ direction (Mathy et al., 2007). To date this is the only 5’-exonuclease known in prokaryotes and its discovery has had important implications in the RNA decay model. The exonucleolytic decay from the 5’-end may explain the stabilizing effect conferred by 5’-stem-loops, 5’-protein binding, 5’-ribosome stalling and the presence of a 5’-triphosphate in B. subtilis (Bechhofer, 2009). It has been suggested that this dual-function enzyme (alone or in complex with RNase J2) catalyses not only the endonucleolytic cleavage of an RNA substrate but also continues the degradation of the generated 5’-end by switching to the 5’-exonucleolytic mode (Li de la Sierra-Gallay et al., 2008). In fact, global analysis of RNase J-depleted B. subtilis strains showed an altered abundance for a large number of mRNA transcripts, indicating that this ribonuclease affects gene expression on a global scale (Durand et al., 2012a; Mader et al., 2008). Interestingly, only the exonucleolytic activity of RNase J1 is dependent on the 5’-end phosphorylation status, as it is blocked by triphosphorylated RNA (Li de la Sierra-Gallay et al., 2008). The complex formed by RNase J1 and J2 changes their individual cleavage activities and specificities (Mathy et al., 2010).
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Rev. Soc. Bras. Med. Trop.  vol.46 número2

Rev. Soc. Bras. Med. Trop. vol.46 número2

collected inside a pediatric ward and neonatal-intensive care unit (ICU) of a Brazilian tertiary hospital. Results: Most (86.4%) of them were found to carry one or more species of bacteria on their external surfaces. The bacteria isolated were Gram-positive bacilli (68.2%) or cocci (40.9%), and Gram-negative bacilli (18.2%). Conclusions: Insects collected inside a hospital were carrying pathogenic bacteria; therefore, one must consider the possibility they may act as mechanical vectors of infections, in especially for debilitated or immune-compromised patients in the hospital environments where the insects were collected.
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Synthesis and spectroscopic characterization of mononuclear/binuclear organotin(IV) complexes with 1H-1,2,4-triazole-3-thiol: Comparative studies of their antibacterial/antifungal potencies

Synthesis and spectroscopic characterization of mononuclear/binuclear organotin(IV) complexes with 1H-1,2,4-triazole-3-thiol: Comparative studies of their antibacterial/antifungal potencies

B. subtilis and P. multocida, and the results were summarized in Table I. The data revealed that the synthesized complexes had significant antimicrobial acti- vities against the pathogenic bacteria as compared to the ligand, which indicates that metallation increased antibacterial activity in accordance with earlier rep- orts. 36 This higher activity may be ascribed to the Tweedy theory, according to which chelation reduces the polarity of the central metal atom because of partial sharing of its positive charge with the ligand, which favours the permeation of the complex through the lipid layer of the membrane. 37,38
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Bioactive proteins against pathogenic and spoilage bacteria

Bioactive proteins against pathogenic and spoilage bacteria

Protein isolates from the soybean and chickpea, as well as their methylated esters, were tested for their inhibitory action against the propagation of pathogenic bacteria in raw milk during its storage at room temperature or under refrigeration. Raw milk was inoculated with a mixed culture of Listeria monocytogenes Scott A and Salmonella enterica serovar Enteritidis strain PT4 at ca. 2 log CFU ml -1 . Aerobic plate count, coliform count, and presumptive E. coli in raw milk treated with esterified legume proteins were inhibited by 2 to 3 log relative to a control after 6 to 8 days of storage at 4°C. At room temperature, bacterial populations (aerobic plate count, coliform count, and presumptive E. coli) in raw milk, treated with esterified legume proteins, were inhibited by ca. 1.5 to 1.6 log relative to the control after 12 h. Supplementation of raw milk with esterified soybean protein could significantly inhibit the counts of the two inoculated pathogens (L. monocytogenes Scott A and Salmonella Enteritidis PT4), initially inoculated at ca. 2 log CFU ml -1 , by ca. 2.4 log and 1.6 log CFU ml -1 , respectively, on day eight of storage under cold conditions. Corresponding reductions amounting to 2.7 and 1.8 log CFU ml -1 were observed after 12 h of storage at room temperature. Supplementation of raw milk with esterified soybean protein (0.5%) reduced the maximum level of titratable acidity to 0.21 and maintained the pH level at 6.4, after 8 days of storage under cold conditions as compared with 4 days for untreated raw milk. Similar results were observed when raw milk was stored at room temperature for 10 h [10] (.
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Atividade Antimicrobiana dos Meis Produzidos por Apis mellifera e Abelhas sem Ferrão...

Atividade Antimicrobiana dos Meis Produzidos por Apis mellifera e Abelhas sem Ferrão...

We evaluated the antimicrobial activity of honey collected from nests of 12 species of native stingless bees commonly found in Brazil and 25 unpasteurized honey samples of Apis mellifera that were identified as being unifloral and one multifloral honey sample. The antimicrobial activity of each honey sample was tested against five species of pathogenic bacteria, a pathogenic fungal species and a pathogenic yeast species, comparing this activity with therapeutic manuka honey produced by Apis mellifera bees in New Zealand from the nectar of Leptospermum scoparium (Myrtaceae). Five of thirteen samples of honey from the stingless bees were bactericidal and eight were fungicidal against the pathogenic fungus Trichophyton rubrum. Only the yeast Candida albicans was resistant to all honey samples. The Apis mellifera honey samples that showed bactericidal activity were caju, romã e cana, none of the A. mellifera honey samples affected the fungus T. rubrum. The honeys from Nannotrigona testaceicornis, Plebeia remote, Tetragona clavipes and Scaptotrigona depilis all had a high degree of antimicrobial activity, they were significantly more efficient in terms of antimicrobial activity than manuka honey, especially against Escherichia coli, Klebsiella pneumoniae and T. rubrum. Artificial honey, made with the main sugars found in honey and with similar water content, had no antimicrobial activity in our analyses. We also made mass spectrometry analyses of the honey samples and found some “fingerprint” characteristics that were associated with antimicrobial activity.
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Oxygen-independent stabilization of hypoxia inducible factor (HIF)-1 during RSV infection.

Oxygen-independent stabilization of hypoxia inducible factor (HIF)-1 during RSV infection.

enterocolitica infections, suggesting HIF-1a activation as a host defense mechanism in this model. Additional studies with Y enterocolitica, S enterica subsp enterica, or E aerogenes, and, moreover, application of their siderophores (yersiniabactin, salmochelin, aerobactin) caused a robust, dose-dependent HIF- 1a response in human epithelia and endothelia, independent of cellular hypoxia. Taken together, such studies demonstrate a role for bacterial siderophores in hypoxia-independent activation of HIF-1a during infection with human pathogenic bacteria [54].Similarly, previous studies on viral infections with RSV have demonstrated induction of HIF-1a in primary human bronchial epithelial cells via a nitric-oxide-dependent pathway [42]. Other studies have identified a crosstalk between viral genes and the HIF- 1a pathway during infections with the human herpesvirus 8 (HHV- 8) [32,68]. Kaposi’s sarcoma-associated herpesvirus (KSHV or HHV-8) is the etiological agent of Kaposi’s sarcoma, a highly vascularized, endothelial-derived tumor. A direct role for KSHV- mediated induction of angiogenesis has been proposed based upon
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Isolation of Escherichia coli and Salmonella spp. from free-ranging wild animals

Isolation of Escherichia coli and Salmonella spp. from free-ranging wild animals

commensal strains are derived from phylogenetic groups A and B1, whereas pathogenic strains generally belong to groups B2 and D. Group B2 is largely composed of ExPEC, which is a heterogeneous group of strains that are able to asymptomatically colonize the intestines of several differ- ent hosts (Smith et al., 2007). Most importantly, a B2 strain that contained eight of the ExPEC genes that were included in our study was only isolated from animals in CSP. These genes encoded for adhesins (papC/papEF and sfa), an iron capture system (fyuA), toxins (hly and cnf1), protectin (traT) and a ColV associated-virulence plasmid (cvaC) (Smith et al., 2007; Bélanger et al., 2011). Although the pathogenicity of these strains to wild animals is unknown, we can hypothesize that these animals were exposed to sources of potentially pathogenic bacteria because extra- intestinal VGs are rare in isolates from wildlife, as has been previously described (Tenaillon et al., 2010).
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