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Sample records for potential respiratory pathogens

  1. Multiplex detection of respiratory pathogens

    DOEpatents

    McBride, Mary [Brentwood, CA; Slezak, Thomas [Livermore, CA; Birch, James M [Albany, CA

    2012-07-31

    Described are kits and methods useful for detection of respiratory pathogens (influenza A (including subtyping capability for H1, H3, H5 and H7 subtypes) influenza B, parainfluenza (type 2), respiratory syncytial virus, and adenovirus) in a sample. Genomic sequence information from the respiratory pathogens was analyzed to identify signature sequences, e.g., polynucleotide sequences useful for confirming the presence or absence of a pathogen in a sample. Primer and probe sets were designed and optimized for use in a PCR based, multiplexed Luminex assay to successfully identify the presence or absence of pathogens in a sample.

  2. Comparison between nasopharyngeal swab and nasal wash, using culture and PCR, in the detection of potential respiratory pathogens

    PubMed Central

    2011-01-01

    Background Nasopharyngeal carriage of potential pathogens is important as it is both the major source of transmission and the prerequisite of invasive disease. New methods for detecting carriage could improve comfort, accuracy and laboratory utility. The aims of this study were to compare the sensitivities of a nasopharyngeal swab (NPS) and a nasal wash (NW) in detecting potential respiratory pathogens in healthy adults using microbiological culture and PCR. Results Healthy volunteers attended for nasal washing and brushing of the posterior nasopharynx. Conventional and real-time PCR were used to detect pneumococcus and meningococcus. Statistical differences between the two nasal sampling methods were determined using a nonparametric Mann-Whitney U test; differences between culture and PCR methods were determined using the McNemar test. Nasal washing was more comfortable for volunteers than swabbing (n = 24). In detection by culture, the NW was significantly more likely to detect pathogens than the NPS (p < 0.00001). Overall, there was a low carriage rate of pathogens in this sample; no significant difference was seen in the detection of bacteria between culture and PCR methods. Conclusions Nasal washing and PCR may provide effective alternatives to nasopharyngeal swabbing and classical microbiology, respectively. PMID:21489228

  3. Effectiveness of Polyvalent Bacterial Lysate and Autovaccines Against Upper Respiratory Tract Bacterial Colonization by Potential Pathogens: A Randomized Study

    PubMed Central

    Zagólski, Olaf; Stręk, Paweł; Kasprowicz, Andrzej; Białecka, Anna

    2015-01-01

    Background Polyvalent bacterial lysate (PBL) is an oral immunostimulating vaccine consisting of bacterial standardized lysates obtained by lysis of different strains of bacteria. Autovaccines are individually prepared based on the results of smears obtained from the patient. Both types of vaccine can be used to treat an ongoing chronic infection. This study sought to determine which method is more effective against nasal colonization by potential respiratory tract pathogens. Material/Methods We enrolled 150 patients with aerobic Gram stain culture and count results indicating bacterial colonization of the nose and/or throat by potential pathogens. The participants were randomly assigned to each of the following groups: 1. administration of PBL, 2. administration of autovaccine, and 3. no intervention (controls). Results Reduction of the bacterial count in Streptococcus pneumoniae-colonized participants was significant after the autovaccine (p<0.001) and PBL (p<0.01). Reduction of the bacterial count of other β-hemolytic streptococcal strains after treatment with the autovaccine was significant (p<0.01) and was non-significant after PBL. In Haemophilus influenzae colonization, significant reduction in the bacterial count was noted in the PBL group (p<0.01). Methicillin-resistant Staphylococcus aureus colonization did not respond to either treatment. Conclusions The autovaccine is more effective than PBL for reducing bacterial count of Streptococcus pneumoniae and β-hemolytic streptococci, while PBL was more effective against Haemophilus influenzae colonization. PMID:26434686

  4. [THE PATHOGENIC POTENTIAL OF MORAXELLA CATARRHALIS AND STAPHYLOCOCCUS EPIDERMIDIS UNDER INFLAMMATORY PROCESSES OF UPPER RESPIRATORY TRACTS].

    PubMed

    Kraeva, L A; Burgasova, O A; Kunilova, E S; Petrova, I S; Tseneva, G Ya; Bespalova, G L

    2015-11-01

    The frequent isolation from biological material of Moraxella catarrhalis under bronchitis and pneumonia and Staphilococcus epidermidis under rhinitis and sinusitis requires profound investigation offactors ofpathogenicity ofthe mentioned microorganisms. The genetic and phenotypic markers of virulence of strains M. catarrhalis and S. epidermidis are examined. Their etiologic role in development of infection processes of respiratory tract and middle ear is determined The most of M catarrhalis strains isolated under bronchitis and pneumonia have gene mcaP responsiblefor production ofprotein McaP that provides adhesion to epithelium cell of host and lipolitic activity of bacteria. The strains isolated from patients with pneumonia had the most adhesive activity. The cluster of genes ICA with leading role of gene icaA is responsible for for availability offactors of intercellular adhesion in Staphilococci strains. In the clinical samples from patients with sinusitis this gene is detected 5 times more frequently than from healthy individuals. In phenotypic tests, expression of gene icaA in S. epidermidis isolated from patients is three times higher than in strains isolated from healthy individuals. To establish etiologic role of M. catarrhalis and S. epidermidis and to develop tactic of therapy of patients with bronchitis, pneumonia and sinusitis complex approach is needed, including detection of genetic and phenotypic markers of virulence in isolated microorganisms.

  5. Particle size and pathogenicity in the respiratory tract

    PubMed Central

    Thomas, Richard James

    2013-01-01

    Particle size dictates where aerosolized pathogens deposit in the respiratory tract, thereafter the pathogens potential to cause disease is influenced by tissue tropism, clearance kinetics and the host immunological response. This interplay brings pathogens into contact with a range of tissues spanning the respiratory tract and associated anatomical structures. In animal models, differential deposition within the respiratory tract influences infection kinetics for numerous select agents. Greater numbers of pathogens are required to infect the upper (URT) compared with the lower respiratory tract (LRT), and in comparison the URT infections are protracted with reduced mortality. Pathogenesis in the URT is characterized by infection of the URT lymphoid tissues, cervical lymphadenopathy and septicemia, closely resembling reported human infections of the URT. The olfactory, gastrointestinal, and ophthalmic systems are also infected in a pathogen-dependent manner. The relevant literature is reviewed with respect to particle size and infection of the URT in animal models and humans. PMID:24225380

  6. Respiratory pathogens: assessing resistance patterns in Europe and the potential role of grepafloxacin as treatment of patients with infections caused by these organisms.

    PubMed

    Felmingham, D

    2000-03-01

    Legionella pneumophila (MIC(90) 0.015 mg/L), Mycoplasma pneumoniae (MIC(90) 0.5 mg/L) and Chlamydia pneumoniae (MICs 0.06-0.12 mg/L). Current susceptibility data indicate that fluoroquinolone resistance rates among bacterial respiratory tract pathogens are low in European countries. The enhanced potency and activity of grepafloxacin against isolates of S. pneumoniae, including those exhibiting resistance to unrelated classes of antibiotics, together with its activity against other respiratory tract pathogens, suggest that this drug has considerable potential as empirical therapy of patients with a wide range of RTI.

  7. Taking forward a 'One Health' approach for turning the tide against the Middle East respiratory syndrome coronavirus and other zoonotic pathogens with epidemic potential.

    PubMed

    Zumla, Alimuddin; Dar, Osman; Kock, Richard; Muturi, Matthew; Ntoumi, Francine; Kaleebu, Pontiano; Eusebio, Macete; Mfinanga, Sayoki; Bates, Matthew; Mwaba, Peter; Ansumana, Rashid; Khan, Mishal; Alagaili, Abdulaziz N; Cotten, Matthew; Azhar, Esam I; Maeurer, Markus; Ippolito, Giuseppe; Petersen, Eskild

    2016-06-01

    The appearance of novel pathogens of humans with epidemic potential and high mortality rates have threatened global health security for centuries. Over the past few decades new zoonotic infectious diseases of humans caused by pathogens arising from animal reservoirs have included West Nile virus, Yellow fever virus, Ebola virus, Nipah virus, Lassa Fever virus, Hanta virus, Dengue fever virus, Rift Valley fever virus, Crimean-Congo haemorrhagic fever virus, severe acute respiratory syndrome coronavirus, highly pathogenic avian influenza viruses, Middle East Respiratory Syndrome Coronavirus, and Zika virus. The recent Ebola Virus Disease epidemic in West Africa and the ongoing Zika Virus outbreak in South America highlight the urgent need for local, regional and international public health systems to be be more coordinated and better prepared. The One Health concept focuses on the relationship and interconnectedness between Humans, Animals and the Environment, and recognizes that the health and wellbeing of humans is intimately connected to the health of animals and their environment (and vice versa). Critical to the establishment of a One Health platform is the creation of a multidisciplinary team with a range of expertise including public health officers, physicians, veterinarians, animal husbandry specialists, agriculturalists, ecologists, vector biologists, viral phylogeneticists, and researchers to co-operate, collaborate to learn more about zoonotic spread between animals, humans and the environment and to monitor, respond to and prevent major outbreaks. We discuss the unique opportunities for Middle Eastern and African stakeholders to take leadership in building equitable and effective partnerships with all stakeholders involved in human and health systems to take forward a 'One Health' approach to control such zoonotic pathogens with epidemic potential.

  8. The bovine paranasal sinuses: Bacterial flora, epithelial expression of nitric oxide and potential role in the in-herd persistence of respiratory disease pathogens.

    PubMed

    Murray, Gerard M; O'Neill, Rónan G; Lee, Alison M; McElroy, Máire C; More, Simon J; Monagle, Aisling; Earley, Bernadette; Cassidy, Joseph P

    2017-01-01

    The bovine paranasal sinuses are a group of complex cavernous air-filled spaces, lined by respiratory epithelium, the exact function of which is unclear. While lesions affecting these sinuses are occasionally reported in cattle, their microbial flora has not been defined. Furthermore, given that the various bacterial and viral pathogens causing bovine respiratory disease (BRD) persist within herds, we speculated that the paranasal sinuses may serve as a refuge for such infectious agents. The paranasal sinuses of clinically normal cattle (n = 99) and of cattle submitted for post-mortem examination (PME: n = 34) were examined by microbial culture, PCR and serology to include bacterial and viral pathogens typically associated with BRD: Mycoplasma bovis, Histophilus somni, Mannheimia haemolytica and Pasteurella multocida, bovine respiratory syncytial virus (BRSV) and bovine parainfluenza-3 virus (BPIV-3). Overall, the paranasal sinuses were either predominantly sterile or did not contain detectable microbes (83.5%: 94.9% of clinically normal and 50.0% of cattle submitted for PME). Bacteria, including BRD causing pathogens, were identified in relatively small numbers of cattle (<10%). While serology indicated widespread exposure of both clinically normal and cattle submitted for PME to BPIV-3 and BRSV (seroprevalences of 91.6% and 84.7%, respectively), PCR identified BPIV-3 in only one animal. To further explore these findings we investigated the potential role of the antimicrobial molecule nitric oxide (NO) within paranasal sinus epithelium using immunohistochemistry. Expression of the enzyme responsible for NO synthesis, inducible nitric oxide synthase (iNOS), was detected to varying degrees in 76.5% of a sub-sample of animals suggesting production of this compound plays a similar protective role in the bovine sinus as it does in humans.

  9. The bovine paranasal sinuses: Bacterial flora, epithelial expression of nitric oxide and potential role in the in-herd persistence of respiratory disease pathogens

    PubMed Central

    O’Neill, Rónan G.; Lee, Alison M.; McElroy, Máire C.; More, Simon J.; Monagle, Aisling; Earley, Bernadette; Cassidy, Joseph P.

    2017-01-01

    The bovine paranasal sinuses are a group of complex cavernous air-filled spaces, lined by respiratory epithelium, the exact function of which is unclear. While lesions affecting these sinuses are occasionally reported in cattle, their microbial flora has not been defined. Furthermore, given that the various bacterial and viral pathogens causing bovine respiratory disease (BRD) persist within herds, we speculated that the paranasal sinuses may serve as a refuge for such infectious agents. The paranasal sinuses of clinically normal cattle (n = 99) and of cattle submitted for post-mortem examination (PME: n = 34) were examined by microbial culture, PCR and serology to include bacterial and viral pathogens typically associated with BRD: Mycoplasma bovis, Histophilus somni, Mannheimia haemolytica and Pasteurella multocida, bovine respiratory syncytial virus (BRSV) and bovine parainfluenza-3 virus (BPIV-3). Overall, the paranasal sinuses were either predominantly sterile or did not contain detectable microbes (83.5%: 94.9% of clinically normal and 50.0% of cattle submitted for PME). Bacteria, including BRD causing pathogens, were identified in relatively small numbers of cattle (<10%). While serology indicated widespread exposure of both clinically normal and cattle submitted for PME to BPIV-3 and BRSV (seroprevalences of 91.6% and 84.7%, respectively), PCR identified BPIV-3 in only one animal. To further explore these findings we investigated the potential role of the antimicrobial molecule nitric oxide (NO) within paranasal sinus epithelium using immunohistochemistry. Expression of the enzyme responsible for NO synthesis, inducible nitric oxide synthase (iNOS), was detected to varying degrees in 76.5% of a sub-sample of animals suggesting production of this compound plays a similar protective role in the bovine sinus as it does in humans. PMID:28282443

  10. Atypical pathogens and respiratory tract infections.

    PubMed

    Blasi, F

    2004-07-01

    The atypical respiratory pathogens Chlamydia pneumoniae, Mycoplasma pneumoniae and Legionella pneumophila are now recognised as a significant cause of acute respiratory-tract infections, implicated in community-acquired pneumonia, acute exacerbations of chronic bronchitis, asthma, and less frequently, upper respiratory-tract infections. Chronic infection with C. pneumoniae is common among patients with chronic obstructive pulmonary disease and may also play a role in the natural history of asthma, including exacerbations. The lack of a gold standard for diagnosis of these pathogens still handicaps the current understanding of their true prevalence and role in the pathogenesis of acute and chronic respiratory infections. While molecular diagnostic techniques, such as polymerase chain reaction, offer improvements in sensitivity, specificity and rapidity over culture and serology, the need remains for a consistent and reproducible diagnostic technique, available to all microbiology laboratories. Current treatment guidelines for community-acquired pneumonia recognise the importance of atypical respiratory pathogens in its aetiology, for which macrolides are considered suitable first-line agents. The value of atypical coverage in antibiotic therapy for acute exacerbations of chronic bronchitis and exacerbations of asthma is less clear, while there is no evidence to suggest that atypical pathogens should be covered in antibiotic treatment of upper respiratory-tract infections.

  11. Crystal Structures of Respiratory Pathogen Neuraminidases

    SciTech Connect

    Hsiao, Y.; Parker, D; Ratner, A; Prince, A; Tong, L

    2009-01-01

    Currently there is pressing need to develop novel therapeutic agents for the treatment of infections by the human respiratory pathogens Pseudomonas aeruginosa and Streptococcus pneumoniae. The neuraminidases of these pathogens are important for host colonization in animal models of infection and are attractive targets for drug discovery. To aid in the development of inhibitors against these neuraminidases, we have determined the crystal structures of the P. aeruginosa enzyme NanPs and S. pneumoniae enzyme NanA at 1.6 and 1.7 {angstrom} resolution, respectively. In situ proteolysis with trypsin was essential for the crystallization of our recombinant NanA. The active site regions of the two enzymes are strikingly different. NanA contains a deep pocket that is similar to that in canonical neuraminidases, while the NanPs active site is much more open. The comparative studies suggest that NanPs may not be a classical neuraminidase, and may have distinct natural substrates and physiological functions. This work represents an important step in the development of drugs to prevent respiratory tract colonization by these two pathogens.

  12. Production of extended-spectrum β-lactamases and the potential indirect pathogenic role of Prevotella isolates from the cystic fibrosis respiratory microbiota

    PubMed Central

    Sherrard, Laura J.; McGrath, Stef J.; McIlreavey, Leanne; Hatch, Joseph; Wolfgang, Matthew C.; Muhlebach, Marianne S.; Gilpin, Deirdre F.; Elborn, J. Stuart; Tunney, Michael M.

    2016-01-01

    Extended-spectrum β-lactamase (ESBL) production and the prevalence of the β-lactamase-encoding gene blaTEM were determined in Prevotella isolates (n = 50) cultured from the respiratory tract of adults and young people with cystic fibrosis (CF). Time–kill studies were used to investigate the concept of passive antibiotic resistance and to ascertain whether a β-lactamase-positive Prevotella isolate can protect a recognised CF pathogen from the action of ceftazidime in vitro. The results indicated that approximately three-quarters (38/50; 76%) of Prevotella isolates produced ESBLs. Isolates positive for ESBL production had higher minimum inhibitory concentrations (MICs) of β-lactam antibiotics compared with isolates negative for production of ESBLs (P < 0.001). The blaTEM gene was detected more frequently in CF Prevotella isolates from paediatric patients compared with isolates from adults (P = 0.002), with sequence analysis demonstrating that 21/22 (95%) partial blaTEM genes detected were identical to blaTEM-116. Furthermore, a β-lactamase-positive Prevotella isolate protected Pseudomonas aeruginosa from the antimicrobial effects of ceftazidime (P = 0.03). Prevotella isolated from the CF respiratory microbiota produce ESBLs and may influence the pathogenesis of chronic lung infection via indirect methods, including shielding recognised pathogens from the action of ceftazidime. PMID:26774156

  13. Evasion of Neutrophil Extracellular Traps by Respiratory Pathogens.

    PubMed

    Storisteanu, Daniel M L; Pocock, Joanna M; Cowburn, Andrew S; Juss, Jatinder K; Nadesalingam, Angalee; Nizet, Victor; Chilvers, Edwin R

    2017-04-01

    The release of neutrophil extracellular traps (NETs) is a major immune mechanism intended to capture pathogens. These histone- and protease-coated DNA structures are released by neutrophils in response to a variety of stimuli, including respiratory pathogens, and have been identified in the airways of patients with respiratory infection, cystic fibrosis, acute lung injury, primary graft dysfunction, and chronic obstructive pulmonary disease. NET production has been demonstrated in the lungs of mice infected with Staphylococcus aureus, Klebsiella pneumoniae, and Aspergillus fumigatus. Since the discovery of NETs over a decade ago, evidence that "NET evasion" might act as an immune protection strategy among respiratory pathogens, including group A Streptococcus, Bordetella pertussis, and Haemophilus influenzae, has been growing, with the majority of these studies being published in the past 2 years. Evasion strategies fall into three main categories: inhibition of NET release by down-regulating host inflammatory responses; degradation of NETs using pathogen-derived DNases; and resistance to the microbicidal components of NETs, which involves a variety of mechanisms, including encapsulation. Hence, the evasion of NETs appears to be a widespread strategy to allow pathogen proliferation and dissemination, and is currently a topic of intense research interest. This article outlines the evidence supporting the three main strategies of NET evasion-inhibition, degradation, and resistance-with particular reference to common respiratory pathogens.

  14. Respiratory Pathogens Adopt a Chronic Lifestyle in Response to Bile

    PubMed Central

    Reen, F. Jerry; Woods, David F.; Mooij, Marlies J.; Adams, Claire; O'Gara, Fergal

    2012-01-01

    Chronic respiratory infections are a major cause of morbidity and mortality, most particularly in Cystic Fibrosis (CF) patients. The recent finding that gastro-esophageal reflux (GER) frequently occurs in CF patients led us to investigate the impact of bile on the behaviour of Pseudomonas aeruginosa and other CF-associated respiratory pathogens. Bile increased biofilm formation, Type Six Secretion, and quorum sensing in P. aeruginosa, all of which are associated with the switch from acute to persistent infection. Furthermore, bile negatively influenced Type Three Secretion and swarming motility in P. aeruginosa, phenotypes associated with acute infection. Bile also modulated biofilm formation in a range of other CF-associated respiratory pathogens, including Burkholderia cepacia and Staphylococcus aureus. Therefore, our results suggest that GER-derived bile may be a host determinant contributing to chronic respiratory infection. PMID:23049911

  15. Prospective Evaluation for Respiratory Pathogens in Children With Sickle Cell Disease and Acute Respiratory Illness

    PubMed Central

    Srinivasan, Ashok; Wang, Winfred C.; Gaur, Aditya; Smith, Teresa; Gu, Zhengming; Kang, Guolian; Leung, Wing; Hayden, Randall T.

    2015-01-01

    Background Human rhinovirus (HRV), human coronavirus (hCoV), human bocavirus (hBoV), and human metapneumovirus (hMPV) infections in children with sickle cell disease have not been well studied. Procedure Nasopharyngeal wash specimens were prospectively collected from 60 children with sickle cell disease and acute respiratory illness, over a 1-year period. Samples were tested with multiplexed-PCR, using an automated system for nine respiratory viruses, Chlamydophila pneumoniae, Mycoplasma pneumoniae, and Bordetella pertussis. Clinical characteristics and distribution of respiratory viruses in patients with and without acute chest syndrome (ACS) were evaluated. Results A respiratory virus was detected in 47 (78%) patients. Nine (15%) patients had ACS; a respiratory virus was detected in all of them. The demographic characteristics of patients with and without ACS were similar. HRV was the most common virus, detected in 29 of 47 (62%) patients. Logistic regression showed no association between ACS and detection of HRV, hCoV, hBoV, hMPV, and other respiratory pathogens. Co-infection with at least one additional respiratory virus was seen in 14 (30%) infected patients, and was not significantly higher in patients with ACS (P=0.10). Co-infections with more than two respiratory viruses were seen in seven patients, all in patients without ACS. Bacterial pathogens were not detected. Conclusion HRV was the most common virus detected in children with sickle cell disease and acute respiratory illness, and was not associated with increased morbidity. Larger prospective studies with asymptomatic controls are needed to study the association of these emerging respiratory viruses with ACS in children with sickle cell disease. PMID:24123899

  16. Simkania negevensis: Is it a real respiratory pathogen?

    PubMed

    Kose, Mehmet; Ekinci, Duygu; Gokahmetoglu, Selma; Elmas, Tuba; Öztürk, Mustafa Kürşad

    2015-06-01

    Simkania negevensis, a recently discovered Chlamydia-like organism, has been associated with respiratory infections such as pneumonia, bronchiolitis and chronic obstructive pulmonary disease in children and adults. The aim of the present study was to evaluate S. negevensis in the etiology of pediatric community-acquired pneumonia, bronchiolitis and asthma exacerbation in our region. Overall, 102 patients and 46 healthy controls were included in the study. S. negevensis was investigated by real time PCR (Primer Design, UK) in nasopharyngeal swab samples. It failed to be detected in either the study or control group. In conclusion, our results suggest that S. negevensis is not an important respiratory pathogen in our region.

  17. The activity of grepafloxacin against respiratory pathogens in the UK.

    PubMed

    Wise, R; Andrews, J M

    1997-12-01

    The in-vitro activity of grepafloxacin was compared with that of other antimicrobials against respiratory tract pathogens collected from 15 UK laboratories over the winter of 1995-96. Penicillin-resistant Streptococcus pneumoniae was not encountered, but macrolide resistance was seen in approximately 10% of strains. Grepafloxacin (MIC90 0.25 mg/L) was four- to eight-fold more active than ciprofloxacin. Twelve percent of Haemophilus influenzae were beta-lactamase producers, macrolides were relatively inactive yet fluoroquinolones were highly active. Moraxella catarrhalis were highly susceptible to fluoroquinolones and macrolides. The activity of grepafloxacin against respiratory tract pathogens should make it a useful agent in the treatment of infections at this site.

  18. Prospective Detection of Respiratory Pathogens in Symptomatic Children with Cancer

    PubMed Central

    Srinivasan, Ashok; Gu, Zhengming; Smith, Teresa; Morgenstern, Markus; Sunkara, Anusha; Kang, Guolian; Srivastava, Deo K.; Gaur, Aditya H.; Leung, Wing; Hayden, Randall T.

    2016-01-01

    Background The data on human rhinovirus (HRV), coronavirus (hCoV), bocavirus (hBoV), metapneumovirus (hMPV), Chlamydophila pneumoniae, Mycoplasma pneumoniae and Bordetella pertussis infections in children with cancer is limited. Methods We sought to determine prospectively the prevalence of respiratory pathogens in these children, using multiplexed-PCR. Results We enrolled 253 children with upper, or lower respiratory tract infection (URTI/LRTI) during a one year period. A respiratory virus was detected in 193 (76%) patients; 156 (81%) patients had URTI. Human rhinovirus was the most common virus detected in 97 (62%) and 24 (65%) patients with URTI and LRTI, respectively. Leukemia or lymphoma (LL) was the most common underlying diagnosis in 95 (49%) patients followed by solid tumor 47 (24%), post-hematopoietic stem cell transplant (HCT) 28 (15%), and brain tumor in 23 (12%) patients. By multiple logistic regression analysis hBoV was the most commonly detected respiratory virus in patients with LRTI (P = 0.008; odds ratio, 4.52; 95% confidence interval, 1.48-13.79). Co-infection with more than 1 virus was present in 47 (24%) patients, and did not increase the risk for LRTI. Two (0.7%) patients succumbed to LRTI from parainfluenza virus (PIV)-3 and respiratory syncytial virus/HRV infection, respectively. C.pneumoniae and M.pneumoniae were detected in 4 and 3 patients, respectively. Conclusions HRV was the most common virus detected in children with cancer and post-HCT hospitalized with an acute respiratory illness, and was not associated with increased morbidity. Prospective studies with viral load determination and asymptomatic controls are needed to study the association of these emerging respiratory viruses with LRTI in children with cancer and post-HCT. PMID:23190778

  19. Pathogenic Potential of Campylobacter ureolyticus

    PubMed Central

    Burgos-Portugal, Jose A.; Kaakoush, Nadeem O.; Raftery, Mark J.

    2012-01-01

    The recent detection and isolation of the aflagellate Campylobacter ureolyticus (previously known as Bacteroides ureolyticus) from intestinal biopsy specimens and fecal samples of children with newly diagnosed Crohn's disease led us to investigate the pathogenic potential of this bacterium. Adherence and gentamicin protection assays were employed to quantify the levels of adherence to and invasion into host cells. C. ureolyticus UNSWCD was able to adhere to the Caco-2 intestinal epithelial cell line with a value of 5.341% ± 0.74% but was not able to invade the Caco-2 cells. The addition of two proinflammatory cytokines, tumor necrosis factor alpha (TNF-α) and gamma interferon (IFN-γ), to the cell line did not affect attachment or invasion, with attachment levels being 4.156% ± 0.61% (P = 0.270) for TNF-α and 6.472% ± 0.61% (P = 0.235) for IFN-γ. Scanning electron microscopy visually confirmed attachment and revealed that C. ureolyticus UNSWCD colonizes and adheres to intestinal cells, inducing cellular damage and microvillus degradation. Purification and identification of the C. ureolyticus UNSWCD secretome detected a total of 111 proteins, from which 29 were bioinformatically predicted to be secretory proteins. Functional classification revealed three putative virulence and colonization factors: the surface antigen CjaA, an outer membrane fibronectin binding protein, and an S-layer RTX toxin. These results suggest that C. ureolyticus has the potential to be a pathogen of the gastrointestinal tract. PMID:22124656

  20. Detection of viral respiratory pathogens in mild and severe acute respiratory infections in Singapore

    PubMed Central

    Jiang, Lili; Lee, Vernon Jian Ming; Cui, Lin; Lin, Raymond; Tan, Chyi Lin; Tan, Linda Wei Lin; Lim, Wei-yen; Leo, Yee-Sin; Low, Louie; Hibberd, Martin; Chen, Mark I-Cheng

    2017-01-01

    To investigate the performance of laboratory methods and clinical case definitions in detecting the viral pathogens for acute respiratory infections (ARIs) from a prospective community cohort and hospital inpatients, nasopharyngeal swabs from cohort members reporting ARIs (community-ARI) and inpatients admitted with ARIs (inpatient-ARI) were tested by Singleplex Real Time-Polymerase Chain Reaction (SRT-PCR), multiplex RT-PCR (MRT-PCR) and pathogen-chip system (PathChip) between April 2012 and December 2013. Community-ARI and inpatient-ARI was also combined with mild and severe cases of influenza from a historical prospective study as mild-ARI and severe-ARI respectively to evaluate the performance of clinical case definitions. We analysed 130 community-ARI and 140 inpatient-ARI episodes (5 inpatient-ARI excluded because multiple pathogens were detected), involving 138 and 207 samples respectively. Detection by PCR declined with days post-onset for influenza virus; decrease was faster for community-ARI than for inpatient-ARI. No such patterns were observed for non-influenza respiratory virus infections. PathChip added substantially to viruses detected for community-ARI only. Clinical case definitions discriminated influenza from other mild-ARI but performed poorly for severe-ARI and for older participants. Rational strategies for diagnosis and surveillance of influenza and other respiratory virus must acknowledge the differences between ARIs presenting in community and hospital settings. PMID:28218288

  1. [Importance of Chlamydia pneumoniae as a new respiratory pathogen].

    PubMed

    Bartolomé, C; Mata, M; Bernárdez, I

    1996-03-01

    The incidence of Chlamydia pneumoniae as a cause of respiratory tract infection was evaluated in a one-year prospective study in 142 patients with community-acquired pneumonia. An indirect immunofluorescence method which detects antibodies in acute and convalescent serum samples was used. Serological evidence of current infection was a four-fold rise in IgG antibody titer or a positive IgM fraction. C. pneumoniae was the causative pathogen in nine patients. This result is similar to those obtained in other studies and suggests that C. pneumoniae is a common etiological agent of community-acquired pneumonia in the studied area.

  2. Comprehensive Molecular Testing for Respiratory Pathogens in Community-Acquired Pneumonia

    PubMed Central

    Gadsby, Naomi J.; Russell, Clark D.; McHugh, Martin P.; Mark, Harriet; Conway Morris, Andrew; Laurenson, Ian F.; Hill, Adam T.; Templeton, Kate E.

    2016-01-01

    Background. The frequent lack of a microbiological diagnosis in community-acquired pneumonia (CAP) impairs pathogen-directed antimicrobial therapy. This study assessed the use of comprehensive multibacterial, multiviral molecular testing, including quantification, in adults hospitalized with CAP. Methods. Clinical and laboratory data were collected for 323 adults with radiologically-confirmed CAP admitted to 2 UK tertiary care hospitals. Sputum (96%) or endotracheal aspirate (4%) specimens were cultured as per routine practice and also tested with fast multiplex real-time polymerase-chain reaction (PCR) assays for 26 respiratory bacteria and viruses. Bacterial loads were also calculated for 8 bacterial pathogens. Appropriate pathogen-directed therapy was retrospectively assessed using national guidelines adapted for local antimicrobial susceptibility patterns. Results. Comprehensive molecular testing of single lower respiratory tract (LRT) specimens achieved pathogen detection in 87% of CAP patients compared with 39% with culture-based methods. Haemophilus influenzae and Streptococcus pneumoniae were the main agents detected, along with a wide variety of typical and atypical pathogens. Viruses were present in 30% of cases; 82% of these were codetections with bacteria. Most (85%) patients had received antimicrobials in the 72 hours before admission. Of these, 78% had a bacterial pathogen detected by PCR but only 32% were culture-positive (P < .0001). Molecular testing had the potential to enable de-escalation in number and/or spectrum of antimicrobials in 77% of patients. Conclusions. Comprehensive molecular testing significantly improves pathogen detection in CAP, particularly in antimicrobial-exposed patients, and requires only a single LRT specimen. It also has the potential to enable early de-escalation from broad-spectrum empirical antimicrobials to pathogen-directed therapy. PMID:26747825

  3. Potential impact of fireworks on respiratory health.

    PubMed

    Gouder, Caroline; Montefort, Stephen

    2014-10-01

    The world-wide use of fireworks with their consequent detrimental effect on the air quality is widely recognized with elevated ambient air levels of particulate matter and its several metallic components and gases identified in several studies carried out during such events. Exposed individuals may be at risk following inhalation of such produced pollutants. This review focuses on the impact of fireworks on air quality and the potential effect of fireworks on the respiratory system of healthy individuals as well as those suffering from underlying respiratory diseases, particularly asthma and chronic obstructive pulmonary disease (COPD). This applies not only to spectators including children but also to pyrotechnicians themselves. An extensive Medline search revealed that a strong evidence of the impact of fireworks on respiratory health is lacking in susceptible as well as healthy individuals with no formal studies on COPD or asthma, other than a few case reports in the latter. The implementation of global strategies to control the use of fireworks and hence improve air quality could possibly reduce their likely detrimental effect on human respiratory health in exposed individuals, but clearly a more targeted research is needed.

  4. Histamine synthesis by respiratory tract micro-organisms: possible role in pathogenicity.

    PubMed Central

    Devalia, J L; Grady, D; Harmanyeri, Y; Tabaqchali, S; Davies, R J

    1989-01-01

    Five bacterial species considered to be potential pathogens in acute exacerbations of chronic bronchitis, cystic fibrosis, and pneumonia--Branhamella catarrhalis, Haemophilus parainfluenzae, Pseudomonas aeruginosa, Staphylococcus aureus and Streptococcus pneumoniae--were evaluated for their potential to synthesise histamine in vitro. Bacterial species commonly isolated from infected sputum but generally not considered to be pathogenic--Enterobacteriacae, Neisseria pharyngis, coagulase negative staphylococci, alpha-haemolytic streptococci, and Candida albicans--were similarly studied. Of the "pathogens", the Gram negative species B catarrhalis, H parainfluenzae and Ps aeruginosa synthesised clinically important amounts of histamine; this was not the case for the Gram positive species S aureus and S pneumoniae. Of the "non-pathogenic" species, only the Enterobacteriacae, as a group, were found to synthesise clinically important amounts of histamine. These results show that some Gram negative bacteria, associated with acute exacerbations in respiratory infections, produce histamine and possibly other inflammatory mediators, which may contribute to their pathogenecity in the lower respiratory tract in vivo. PMID:2499609

  5. Clinical differences between respiratory viral and bacterial mono- and dual pathogen detected among Singapore military servicemen with febrile respiratory illness

    PubMed Central

    Ho, Zheng Jie Marc; Zhao, Xiahong; Cook, Alex R; Loh, Jin Phang; Ng, Sock Hoon; Tan, Boon Huan; Lee, Vernon J

    2015-01-01

    Background Although it is known that febrile respiratory illnesses (FRI) may be caused by multiple respiratory pathogens, there are no population-level studies describing its impact on clinical disease. Methods Between May 2009 and October 2012, 7733 FRI patients and controls in the Singapore military had clinical data and nasal wash samples collected prospectively and sent for PCR testing. Patients with one pathogen detected (mono-pathogen) were compared with those with two pathogens (dual pathogen) for differences in basic demographics and clinical presentation. Results In total, 45.8% had one pathogen detected, 20.2% had two pathogens detected, 30.9% had no pathogens detected, and 3.1% had more than two pathogens. Multiple pathogens were associated with recruits, those with asthma and non-smokers. Influenza A (80.0%), influenza B (73.0%) and mycoplasma (70.6%) were most commonly associated with mono-infections, while adenovirus was most commonly associated with dual infections (62.9%). Influenza A paired with S. pneumoniae had higher proportions of chills and rigors than their respective mono-pathogens (P = 0.03, P = 0.009). H. influenzae paired with either enterovirus or parainfluenzae had higher proportions of cough with phlegm than their respective mono-pathogens. Although there were observed differences in mean proportions of body temperature, nasal symptoms, sore throat, body aches and joint pains between viral and bacterial mono-pathogens, there were few differences between distinct dual-pathogen pairs and their respective mono-pathogen counterparts. Conclusion A substantial number of FRI patients have multiple pathogens detected. Observed clinical differences between patients of dual pathogen and mono-pathogen indicate the likely presence of complex microbial interactions between the various pathogens. PMID:25827870

  6. The Pathogenic Potential of a Microbe

    PubMed Central

    2017-01-01

    ABSTRACT Virulence is a microbial property that is realized only in susceptible hosts. There is no absolute measurement for virulence, and consequently it is always measured relative to a standard, usually another microbe or host. This article introduces the concept of pathogenic potential, which provides a new approach to measuring the capacity of microbes for virulence. The pathogenic potential is proportional to the fraction of individuals who become symptomatic after infection with a defined inoculum and can include such attributes as mortality, communicability, and the time from infection to disease. The calculation of the pathogenic potential has significant advantages over the use of the lethal dose that kills 50% of infected individuals (LD50) and allows direct comparisons between individual microbes. An analysis of the pathogenic potential of several microbes for mice reveals a continuum, which in turn supports the view that there is no dividing line between pathogenic and nonpathogenic microbes. PMID:28251180

  7. In-vitro activity of sparfloxacin in comparison with currently available antimicrobials against respiratory tract pathogens.

    PubMed

    Baquero, F; Cantón, R

    1996-05-01

    Bacterial resistance to antimicrobial agents is an ever-increasing problem. The in-vitro activity of sparfloxacin compared with that of currently available antimicrobial agents against pathogens implicated in respiratory tract infections is reviewed. Sparfloxacin is a fluoroquinolone active against both penicillin-susceptible and -resistant strains of Streptococcus pneumoniae. It is also active against many other respiratory tract pathogens and may be a suitable alternative for empirical therapy of community-acquired respiratory tract infections.

  8. Concordance in diagnostic testing for respiratory pathogens of bighorn sheep

    USGS Publications Warehouse

    Walsh, Daniel P.; Cassirer, E. Frances; Bonds, Michael D.; Brown, Daniel R.; Edwards, William H.; Weiser, Glen C.; Drew, Mark L.; Briggs, Robert E.; Fox, Karen A.; Miller, Michael W.; Shanthalingam, Sudarvili; Srikumaran, Subramaniam; Besser, Thomas E.

    2016-01-01

    Reliable diagnostic tests are essential for disease investigation and management. This is particularly true for diseases of free-ranging wildlife where sampling is logistically difficult precluding retesting. Clinical assays for wildlife diseases frequently vary among laboratories because of lack of appropriate standardized commercial kits. Results of diagnostic testing may also be called into question when investigators report different etiologies for disease outbreaks, despite similar clinical and pathologic findings. To evaluate reliability of diagnostic testing for respiratory pathogens of bighorn sheep (Ovis canadensis), we conducted a series of ring tests across 6 laboratories routinely involved in detection of Mycoplasma ovipneumoniae, Pasteurellaceae, lktA (the Pasteurellaceae gene encoding leukotoxin), and 3 reference laboratories. Consistency of results for replicate samples within laboratories was high (median agreement = 1.0). Agreement between laboratories was high for polymerase chain reaction (PCR) detection of M. ovipneumoniae and culture isolation of Mannheimia spp. and Bibersteinia trehalosi(median agreement = 0.89–0.95, Kappa = 0.65–0.74), and lower for PCR detection of Mannheimiaspp. lktA (median agreement = 0.58, Kappa = 0.12). Most errors on defined status samples were false negatives, suggesting test sensitivity was a greater problem than specificity. However, tests for M. haemolytica and lktA yielded some false positive results. Despite differences in testing protocols, median agreement among laboratories and correct classification of controls for most agents was ≥0.80, meeting or exceeding the standard required by federal proficiency testing programs. This information is valuable for interpreting test results, laboratory quality assessments, and advancing diagnosis of respiratory disease in wild sheep. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

  9. Comparison of four multiplex PCR assays for the detection of viral pathogens in respiratory specimens.

    PubMed

    Anderson, Trevor P; Werno, Anja M; Barratt, Kevin; Mahagamasekera, Patalee; Murdoch, David R; Jennings, Lance C

    2013-08-01

    Multiplex PCR has become the test of choice for the detection of multiple respiratory viruses in clinical specimens. However, there are few direct comparisons of different PCR assays. This study compares 4 different multiplex PCR assays for the recovery of common respiratory viruses. We tested 213 respiratory specimens using four different multiplex PCR assays: the xTAG respiratory viral panel fast (Abbott Molecular Laboratories), Fast-track Respiratory Pathogen assay (Fast-track Diagnostics), Easyplex respiratory pathogen 12 kit (Ausdiagnostics), and an in-house multiplex real-time PCR assay. The performance of the four assays was very similar, with 93-100% agreement for all comparisons. Other issues, such as through-put, technical requirements and cost, are likely to be as important for making a decision about which of these assays to use given their comparative performance.

  10. Is There Still Room for Novel Viral Pathogens in Pediatric Respiratory Tract Infections?

    PubMed Central

    Taboada, Blanca; Espinoza, Marco A.; Isa, Pavel; Aponte, Fernando E.; Arias-Ortiz, María A.; Monge-Martínez, Jesús; Rodríguez-Vázquez, Rubén; Díaz-Hernández, Fidel; Zárate-Vidal, Fernando; Wong-Chew, Rosa María; Firo-Reyes, Verónica; del Río-Almendárez, Carlos N.; Gaitán-Meza, Jesús; Villaseñor-Sierra, Alberto; Martínez-Aguilar, Gerardo; Salas-Mier, Ma. del Carmen; Noyola, Daniel E.; Pérez-Gónzalez, Luis F.; López, Susana; Santos-Preciado, José I.; Arias, Carlos F.

    2014-01-01

    Viruses are the most frequent cause of respiratory disease in children. However, despite the advanced diagnostic methods currently in use, in 20 to 50% of respiratory samples a specific pathogen cannot be detected. In this work, we used a metagenomic approach and deep sequencing to examine respiratory samples from children with lower and upper respiratory tract infections that had been previously found negative for 6 bacteria and 15 respiratory viruses by PCR. Nasal washings from 25 children (out of 250) hospitalized with a diagnosis of pneumonia and nasopharyngeal swabs from 46 outpatient children (out of 526) were studied. DNA reads for at least one virus commonly associated to respiratory infections was found in 20 of 25 hospitalized patients, while reads for pathogenic respiratory bacteria were detected in the remaining 5 children. For outpatients, all the samples were pooled into 25 DNA libraries for sequencing. In this case, in 22 of the 25 sequenced libraries at least one respiratory virus was identified, while in all other, but one, pathogenic bacteria were detected. In both patient groups reads for respiratory syncytial virus, coronavirus-OC43, and rhinovirus were identified. In addition, viruses less frequently associated to respiratory infections were also found. Saffold virus was detected in outpatient but not in hospitalized children. Anellovirus, rotavirus, and astrovirus, as well as several animal and plant viruses were detected in both groups. No novel viruses were identified. Adding up the deep sequencing results to the PCR data, 79.2% of 250 hospitalized and 76.6% of 526 ambulatory patients were positive for viruses, and all other children, but one, had pathogenic respiratory bacteria identified. These results suggest that at least in the type of populations studied and with the sampling methods used the odds of finding novel, clinically relevant viruses, in pediatric respiratory infections are low. PMID:25412469

  11. Detection of pathogens in Boidae and Pythonidae with and without respiratory disease.

    PubMed

    Schmidt, V; Marschang, R E; Abbas, M D; Ball, I; Szabo, I; Helmuth, R; Plenz, B; Spergser, J; Pees, M

    2013-03-02

    Respiratory diseases in boid snakes are common in captivity, but little information is available on their aetiology. This study was carried out to determine the occurrence of lung associated pathogens in boid snakes with and without respiratory signs and/or pneumonia. In total, 80 boid snakes of the families Boidae (n = 30) and Pythonidae (n = 50) from 48 private and zoo collections were included in this survey. Husbandry conditions were evaluated using a detailed questionnaire. All snakes were examined clinically and grouped into snakes with or without respiratory signs. Tracheal wash samples from all snakes were examined bacteriologically as well as virologically. All snakes were euthanased, and a complete pathological examination was performed. Respiratory signs and pneumonia were detected more often in pythons than in boas. An acute catarrhal pneumonia was diagnosed more often in snakes without respiratory signs than in snakes with respiratory signs, which revealed fibrinous and fibrous pneumonia. Poor husbandry conditions are an important trigger for the development of respiratory signs and pneumonia. Different bacterial pathogens were isolated in almost all snakes with pneumonia, with Salmonella species being the most common. Ferlavirus (formerly known as ophidian paramyxovirus)-RNA was detected only in pythons. Inclusion body disease was rarely seen in pythons but often in boas. Adenovirus and Mycoplasma were other pathogens that were diagnosed in single snakes with pneumonia. In living boid snakes with respiratory signs, tracheal wash samples were found to be a useful diagnostic tool for the detection of viral and bacterial pathogens.

  12. The upper respiratory tract microbiome and its potential role in bovine respiratory disease and otitis media

    PubMed Central

    Lima, Svetlana F.; Teixeira, Andre Gustavo V.; Higgins, Catherine H.; Lima, Fabio S.; Bicalho, Rodrigo C.

    2016-01-01

    The upper respiratory tract (URT) hosts a complex microbial community of commensal microorganisms and potential pathogens. Analyzing the composition and nature of the healthy URT microbiota and how it changes over time will contribute to a better understanding of the pathogenesis of pneumonia and otitis. A longitudinal study was conducted including 174 Holstein calves that were divided in four groups: healthy calves, calves diagnosed with pneumonia, otitis or both diseases. Deep pharyngeal swabs were collected on days 3, 14, 28, and 35 of life, and next-generation sequencing of the 16S rRNA gene as well as quantitative PCR was performed. The URT of Holstein dairy calves aged 3 to 35 days revealed to host a highly diverse bacterial community. The relative abundances of the bacterial genera Mannheimia, Moraxella, and Mycoplasma were significantly higher in diseased versus healthy animals, and the total bacterial load of newborn calves at day 3 was higher for animals that developed pneumonia than for healthy animals. Our results corroborate the existing knowledge that species of Mannheimia and Mycoplasma are important pathogens in pneumonia and otitis. Furthermore, they suggest that species of Moraxella can potentially cause the same disorders (pneumonia and otitis), and that high neonatal bacterial load is a key contributor to the development of pneumonia. PMID:27363739

  13. Non-diphtheriae Corynebacterium species: an emerging respiratory pathogen.

    PubMed

    Díez-Aguilar, M; Ruiz-Garbajosa, P; Fernández-Olmos, A; Guisado, P; Del Campo, R; Quereda, C; Cantón, R; Meseguer, M A

    2013-06-01

    The purpose of the study was to describe the microbiological and clinical features of ten cases of lower respiratory tract infection due to Corynebacterium striatum, Corynebacterium propinquum and Corynebacterium pseudodiphtheriticum. Respiratory samples were recovered from hospitalised patients who were diagnosed of pneumonia and exacerbations of chronic respiratory infections. The samples were Gram-stained and seeded on conventional bacterial growing media. Bacteria were identified by matrix-assisted linear desorption/ionisation-time-of-flight mass spectrometry (MALDI-TOF MS). Antibiotic susceptibility was tested by the disk diffusion method. All patients presented an acute respiratory onset, most of them in the context of an underlying disease and/or immunosuppression. In all patients, the microscopical examination of Gram-stained respiratory samples showed numerous polymorphonuclear cells and Gram-positive bacilli, suggestive of the Corynebacterium morphotype. A pure culture growth of Corynebacterium was obtained in the majority (72 %) of samples. The conclusions are that non-diphtheriae Corynebacterium species are an emerging cause of respiratory infection among patients with chronic respiratory disease and/or immunosuppression, and cannot always be considered as mere colonisers. The microorganism's predominance in Gram-stained purulent respiratory samples together with abundant growth in the culture is the key for the microbiological diagnosis.

  14. Expression of the Bovine NK-Lysin Gene Family and Activity against Respiratory Pathogens

    PubMed Central

    Chen, Junfeng; Yang, Chingyuan; Tizioto, Polyana C.; Huang, Huan; Lee, Mi O. K.; Payne, Harold R.; Lawhon, Sara D.; Schroeder, Friedhelm; Taylor, Jeremy F.; Womack, James E.

    2016-01-01

    Unlike the genomes of many mammals that have a single NK-lysin gene, the cattle genome contains a family of four genes, one of which is expressed preferentially in the lung. In this study, we compared the expression of the four bovine NK-lysin genes in healthy animals to animals challenged with pathogens known to be associated with bovine respiratory disease (BRD) using transcriptome sequencing (RNA-seq). The expression of several NK-lysins, especially NK2C, was elevated in challenged relative to control animals. The effects of synthetic peptides corresponding to functional region helices 2 and 3 of each gene product were tested on both model membranes and bio-membranes. Circular dichroism spectroscopy indicated that these peptides adopted a more helical secondary structure upon binding to an anionic model membrane and liposome leakage assays suggested that these peptides disrupt membranes. Bacterial killing assays further confirmed the antimicrobial effects of these peptides on BRD-associated bacteria, including both Pasteurella multocida and Mannhemia haemolytica and an ultrastructural examination of NK-lysin-treated P. multocida cells by transmission electron microscopy revealed the lysis of target membranes. These studies demonstrate that the expanded bovine NK-lysin gene family is potentially important in host defense against pathogens involved in bovine respiratory disease. PMID:27409794

  15. Clinical Evaluation of the New High-Throughput Luminex NxTAG Respiratory Pathogen Panel Assay for Multiplex Respiratory Pathogen Detection

    PubMed Central

    Lam, Ho-Yin; Yip, Cyril C. Y.; Wong, Sally C. Y.; Chan, Jasper F. W.; Ma, Edmond S. K.; Cheng, Vincent C. C.; Tang, Bone S. F.

    2016-01-01

    A broad range of viral and bacterial pathogens can cause acute respiratory tract infection. For rapid detection of a broad respiratory pathogen spectrum, multiplex real-time PCR is ideal. This study evaluated the performance of the new Luminex NxTAG Respiratory Pathogen Panel (NxTAG-RPP) in comparison with the BioFire FilmArray Respiratory Panel (FA-RP) or singleplex real-time PCR as reference. A total of 284 clinical respiratory specimens and 3 influenza A/H7N9 viral culture samples were tested. All clinical specimens were processed and analyzed in parallel using NxTAG-RPP and the reference standard method. The H7N9 viral culture samples were tested using NxTAG-RPP only. Overall, the NxTAG-RPP demonstrated ≥93% sensitivity and specificity for all respiratory targets except human coronavirus OC43 (HCoV-OC43) and HCoV-HKU1. The H7N9 virus was detected by the influenza A virus matrix gene target, while other influenza A virus subtyping gene targets in the panel remained negative. Complete concordance between NxTAG-RPP and FA-RP was observed in 98.8% (318/322) of positive results (kappa = 0.92). Substantial agreement was found for most respiratory targets, but significant differences were observed in human metapneumovirus (P = 0.001) and parainfluenza virus type 3 (P = 0.031). NxTAG-RPP has a higher sample throughput than FA-RP (96 samples versus 1 sample per run) while the turnaround times for NxTAG-RPP and FA-RP were 5 h (up to 96 samples) and 1 h (for one sample), respectively. Overall, NxTAG-RPP demonstrated good diagnostic performance for most respiratory pathogens. The high sample throughput with reasonable turnaround time of this new assay makes it a suitable multiplex platform for routine screening of respiratory specimens in hospital-based laboratories. PMID:27122380

  16. Comparison of Luminex NxTAG Respiratory Pathogen Panel and xTAG Respiratory Viral Panel FAST Version 2 for the Detection of Respiratory Viruses.

    PubMed

    Lee, Chun Kiat; Lee, Hong Kai; Ng, Christopher Wei Siong; Chiu, Lily; Tang, Julian Wei Tze; Loh, Tze Ping; Koay, Evelyn Siew Chuan

    2017-05-01

    Owing to advancements in molecular diagnostics, recent years have seen an increasing number of laboratories adopting respiratory viral panels to detect respiratory pathogens. In December 2015, the NxTAG respiratory pathogen panel (NxTAG RPP) was approved by the United States Food and Drug Administration. We compared the clinical performance of this new assay with that of the xTAG respiratory viral panel (xTAG RVP) FAST v2 using 142 clinical samples and 12 external quality assessment samples. Discordant results were resolved by using a laboratory-developed respiratory viral panel. The NxTAG RPP achieved 100% concordant negative results and 86.6% concordant positive results. It detected one coronavirus 229E and eight influenza A/H3N2 viruses that were missed by the xTAG RVP FAST v2. On the other hand, the NxTAG RPP missed one enterovirus/rhinovirus and one metapneumovirus that were detected by FAST v2. Both panels correctly identified all the pathogens in the 12 external quality assessment samples. Overall, the NxTAG RPP demonstrated good diagnostic performance. Of note, it was better able to subtype the influenza A/H3N2 viruses compared with the xTAG RVP FAST v2.

  17. Clinical Evaluation of the Luminex NxTAG Respiratory Pathogen Panel

    PubMed Central

    Gonsalves, Sarah; Sun, Janet Y.; Stiles, Jeffrey; Gilhuley, Kathleen A.; Mikhlina, Albina; Dunbar, Sherry A.; Zhang, Hongwei

    2016-01-01

    An evaluation of the Luminex NxTAG Respiratory Pathogen Panel was performed on 404 clinical respiratory specimens. Clinical sensitivities and specificities of the assay compared to those of the reference methods were 80.0% to 100.0% and 98.9% to 100.0%, respectively. Correct genotyping information was provided for 95.5% of influenza virus A specimens. The closed-tube format of the assay simplified the workflow and minimized carryover contamination. PMID:27122378

  18. Molecular versus conventional culture for detection of respiratory bacterial pathogens in poultry.

    PubMed

    Ammar, A M; Abd El-Aziz, N K; Abd El Wanis, S; Bakry, N R

    2016-02-29

    Acute respiratory tract infections are leading causes of morbidity in poultry farms allover the world. Six pathogens; Escherichia coli, Mycoplasma gallisepticum, Staphylococcus aureus, Pasteurella multocida, Mannheimia haemolytica and Pseudomonas aeruginosa were involved in respiratory infections in poultry. Herein, conventional identification procedures and polymerase chain reaction (PCR) were applied for detection of the most common respiratory bacterial pathogens in clinical specimens of poultry obtained from 53 Egyptian farms with various respiratory problems and the results were compared statistically. The analyzed data demonstrated a significantly higher rate of detection of the most recovered microorganisms (P<0.05) by PCR comparing to classical culture procedures. Further, multiplex PCR could detect E. coli, M. gallisepticum, S. aureus and Ps. aeruginosa in a single reaction, however, M. haemolytica was reported in a uinplex system. According to PCR results, the most commonly recorded bacterial pathogens in examined poultry farms were E. coli and Ps. aeruginosa (54.71% each), followed by M. haemolylica (35.85%) and M. gallisepticum (20.75%). In conclusion, PCR assay offered an effective alternative to traditional typing methods for the identification and simultaneous detection of the most clinically relevant respiratory pathogens in poultry.

  19. Human metapneumovirus: review of an important respiratory pathogen.

    PubMed

    Panda, Swagatika; Mohakud, Nirmal Kumar; Pena, Lindomar; Kumar, Subrat

    2014-08-01

    Human metapneumovirus (hMPV), discovered in 2001, most commonly causes upper and lower respiratory tract infections in young children, but is also a concern for elderly subjects and immune-compromised patients. hMPV is the major etiological agent responsible for about 5% to 10% of hospitalizations of children suffering from acute respiratory tract infections. hMPV infection can cause severe bronchiolitis and pneumonia in children, and its symptoms are indistinguishable from those caused by human respiratory syncytial virus. Initial infection with hMPV usually occurs during early childhood, but re-infections are common throughout life. Due to the slow growth of the virus in cell culture, molecular methods (such as reverse transcriptase PCR (RT-PCR)) are the preferred diagnostic modality for detecting hMPV. A few vaccine candidates have been shown to be effective in preventing clinical disease, but none are yet commercially available. Our understanding of hMPV has undergone major changes in recent years and in this article we will review the currently available information on the molecular biology and epidemiology of hMPV. We will also review the current therapeutic interventions and strategies being used to control hMPV infection, with an emphasis on possible approaches that could be used to develop an effective vaccine against hMPV.

  20. Detection of respiratory tract pathogens with molecular biology methods.

    PubMed

    Wozniak-Kosek, A; Kosek, J; Zielnik-Jurkiewicz, B

    2015-01-01

    This paper describes the use in routine diagnosis of virological kit, which was designed to identify the 15 most common respiratory viruses in clinical specimens of nasopharyngeal aspirates, swabs, and bronchoalveolar lavage. It is a one-step multiplex RT-PCR system for the detection of influenza virus type A and type B, human respiratory syncytial virus type A, B; human adenovirus, human metapneumovirus, human coronaviruses 229E/NL63 and OC43, human parainfluenza type 1, 2, 3, human rhinovirus type A, B, human enterovirus, and bocavirus 1, 2, 3, 4. The article presents research conducted on the basis of swabs collected from patients who came to the Ear, Nose, and Throat Emergency Care Unit at the Department of Otolaryngology, Military Medical Institute in Warsaw, in February 2013. Due to the nature of work in an laryngological emergency ward, the material was collected only from those patients who reported problems associated with rhinitis or any dysfunction of the upper respiratory tract. The study shows that patients who came to seek laryngological assistance were usually infected with viruses having affinity for the airway epithelium.

  1. Potentiation of Taishan Pinus massoniana pollen polysaccharide on the immune response and protection elicited by a highly pathogenic porcine reproductive and respiratory syndrome virus glycoprotein 5 subunit in pigs.

    PubMed

    Peng, Jun; Yuan, Yanmei; Du, Yijun; Wu, Jiaqiang; Li, Baoquan; Li, Jun; Yu, Jiang; Hu, Liping; Shen, Si; Wang, Jinbao; Zhu, Ruiliang

    2016-04-01

    Porcine reproductive and respiratory syndrome virus (PRRSV) heavily affects the global pork industry. Current available vaccine strategies have inherent drawbacks. In this work, the immune enhancement from Taishan Pinus massoniana pollen polysaccharide (TPPPS) and Freund's adjuvant on the efficacy of a PRRSV subunit vaccine were examined. Titers of specific anti-highly pathogenic PRRSV (HP-PRRSV) ELISA antibody and neutralizing antibody were significantly higher in pigs from the groups inoculated with medium- and high-dose TPPPS (mTPPPS, hTPPPS) adjuvant co-administered with a recombinant HP-PRRSV glycoprotein 5 subunit (GP5) than those from other groups (P < 0.05). Pigs inoculated with GP5 + Freund's adjuvant developed severely delayed humoral immune responses specific to GP5 within 28 days post-inoculation (dpi). The groups treated with mTPPPS and hTPPPS adjuvant exhibited the most potent immune enhancement effects on GP5 inoculation with cellular immunity developing, as shown by the level of T lymphocyte proliferation and the percentage of the CD3(+) T lymphocyte subpopulation. Although complete Freund's adjuvant elicited cell-mediated immune responses, the level of T lymphocyte proliferation in this group decreased quickly and no significant differences were observed compared with other adjuvant-alone groups at 56 dpi (P > 0.05). The ratio between CD3(+)CD4(+) and CD3(+)CD8(+) T lymphocyte subpopulations indicated the inoculums of GP5 + mTPPPS and GP5 + hTPPPS induced consistently higher CD3(+)CD4(+) T lymphocyte subpopulations than other inoculums (P < 0.05). The immune responses caused by complete Freund's adjuvant were mainly mediated by CD3(+)CD8(+) T lymphocyte subpopulation (cytotoxic T lymphocytes) in the early stage of inoculation and had no significant difference compared with other adjuvant-alone groups after 28 dpi (P > 0.05). The low-dose TPPPS (lTPPPS) adjuvant also exhibited enhancement effects on humoral immune and T lymphocyte proliferation

  2. Comparative Respiratory Pathogenicity and Dynamic Tissue Distribution of Chinese Highly Pathogenic Porcine Reproductive and Respiratory Syndrome Virus and its Attenuated Strain in Piglets.

    PubMed

    Liu, C; Zhang, W; Gong, W; Zhang, D; She, R; Xu, B; Ning, Y

    2015-07-01

    The outbreak of highly pathogenic porcine reproductive and respiratory syndrome (HP-PRRS) in 2006 devastated the Chinese swine industry. HP-PRRS virus is still the predominant strain in mainland China, rather than the classical PRRSV strain, and the attenuated live vaccine remains the preferred choice for protecting piglets against HP-PRRSV infection. To fully evaluate the safety of strain GDr180, the 180th attenuated virus of the HP-PRRSV strain GD, we used clinicopathological, microscopical, ultrastructural, serological and molecular biological methods to assess the different clinical manifestations and respiratory characteristics of piglets inoculated with HP-PRRSV strain GD or strain GDr180. The 5-week-old piglets inoculated with strain GD displayed marked clinical signs, including fever, anorexia, dyspnoea and tachypnoea. Significant interstitial pneumonia was present, characterized by thickened alveolar septa infiltrated with mononuclear cells and cell debris. However, the piglets inoculated with strain GDr180 and the negative control piglets showed neither clinical signs nor microscopical or ultrastructural lesions. Ultrastructural observation of the piglets' tracheas and examination of the dynamic tissue distributions of PRRSV strain GD and attenuated strain GDr180, by immunohistochemistry and fluorescence quantitative reverse transcription-polymerase chain reaction, confirmed significant differences in their pathogenicity and distribution in the respiratory systems of piglets. The differences in pathogenicity are attributable to the different severity of the pathological changes in the pigs inoculated with the two strains. Thus, the HP-PRRSV GDr180 strain is practically harmless to the respiratory systems of piglets and may be a safe candidate for inducing immunity against HP-PRRS.

  3. Effect of Bovine Respiratory Disease and Overall Pathogenic Disease Incidence on Carcass Traits

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective was to evaluate the effects of incidence of bovine respiratory disease (BRD) and overall incidence of pathogenic diseases (IPD) on carcass traits. Two independent populations were used; the first population comprised crossbred steers (GPE7; n=642) derived from sires of seven Bos tauru...

  4. Reverse Transcription-PCR–Electrospray Ionization Mass Spectrometry for Rapid Detection of Biothreat and Common Respiratory Pathogens

    PubMed Central

    Jeng, Kevin; Rothman, Richard; Yang, Samuel; Won, Helen; Peterson, Stephen; Hsieh, Yu-Hsiang; Masek, Billie Jo; Carroll, Karen C.; Gaydos, Charlotte A.

    2013-01-01

    Electrospray ionization mass spectrometry (ESI-MS) analysis of reverse transcription (RT)-PCR amplicons from human respiratory samples allows for broad pathogen identification approximately 8 h after collection. We investigated the performance characteristics of a high-throughput RT-PCR-coupled ESI-MS assay for distinguishing biothreat (BT) agents from common bacterial, fungal, and viral respiratory pathogens in bronchoalveolar lavage (BAL) fluid specimens from subjects with suspected respiratory infections. In a retrospective case series, 202 BAL fluid specimens were collected at the Johns Hopkins Hospital between August 2010 and February 2011 from patients with suspected acute respiratory infections. Samples were processed using standard bacterial, viral, and fungal testing in the clinical microbiology laboratory as part of routine care and then were blindly spiked with either water or nucleic acids from BT organisms (Bacillus anthracis, Yersinia pestis, Francisella tularensis, Brucella spp., Burkholderia spp., and Rickettsia prowazekii) and tested by RT-PCR–ESI-MS. The sensitivities and specificities of RT-PCR–ESI-MS versus standard clinical methods were as follows: for mock BT DNA, 98.5% sensitivity (95% confidence interval [CI], 94.2 to 99.7%) and 100% specificity (95% CI, 93.1 to 100.0%); for bacterial pathogens, 81.8% sensitivity (95% CI, 74.3 to 87.6%) and 73.6% specificity (95% CI, 64.2 to 81.4%); for viral pathogens, 93.3% sensitivity (95% CI, 66.0 to 99.7%) and 97.3% specificity (95% CI, 89.7 to 99.5%); for fungal pathogens, 42.6% sensitivity (95% CI, 29.5 to 56.7%) and 97.8% specificity (95% CI, 91.8 to 99.6%). Our data suggest that RT-PCR–ESI-MS is a useful adjunct to standard culture protocols for rapid detection of both BT and common respiratory pathogens; further study is required for assay validation, especially for fungal detection, and potential implementation. PMID:23903543

  5. The role and regulation of catalase in respiratory tract opportunistic bacterial pathogens.

    PubMed

    Eason, Mia M; Fan, Xin

    2014-09-01

    Respiratory tract bacterial pathogens are the etiologic agents of a variety of illnesses. The ability of these bacteria to cause disease is imparted through survival within the host and avoidance of pathogen clearance by the immune system. Respiratory tract pathogens are continually bombarded by reactive oxygen species (ROS), which may be produced by competing bacteria, normal metabolic function, or host immunological responses. In order to survive and proliferate, bacteria have adapted defense mechanisms to circumvent the effects of ROS. Bacteria employ the use of anti-oxidant enzymes, catalases and catalase-peroxidases, to relieve the effects of the oxidative stressors to which they are continually exposed. The decomposition of ROS has been shown to provide favorable conditions in which respiratory tract opportunistic bacterial pathogens such as Haemophilus influenzae, Mycobacterium tuberculosis, Legionella pneumophila, and Neisseria meningitidis are able to withstand exposure to highly reactive molecules and yet survive. Bacteria possessing mutations in the catalase gene have a decreased survival rate, yet may be able to compensate for the lack of catalatic activity if peroxidatic activity is present. An incomplete knowledge of the mechanisms by which catalase and catalase-peroxidases are regulated still persists, however, in some bacterial species, a regulatory factor known as OxyR has been shown to either up-regulate or down-regulate catalase gene expression. Yet, more research is still needed to increase the knowledge base in relation to this enzyme class. As with this review, we focus on major respiratory tract opportunistic bacterial pathogens in order to elucidate the function and regulation of catalases. The importance of the research could lead to the development of novel treatments against respiratory bacterial infections.

  6. Simultaneous Detection of Nine Key Bacterial Respiratory Pathogens Using Luminex xTAG® Technology

    PubMed Central

    Jiang, Luxi; Ren, Hongyu; Zhou, Haijian; Qin, Tian; Chen, Yu

    2017-01-01

    Early diagnosis and treatment are crucial to the outcome of lower respiratory tract infections (LRTIs). In this study, we developed an assay combining multiplex PCR and Luminex technology (MPLT) for the detection of nine important respiratory bacterial pathogens, which frequently cause LRTIs. These were Streptococcus pneumoniae, Moraxella catarrhalis, Staphylococcus aureus, Streptococcus pyogenes, Haemophilus influenzae, Mycoplasma pneumoniae, Legionella spp., Pseudomonas aeruginosa, and Klebsiella pneumoniae. Through the hybridization reaction between two new synthesized multiplex PCR products and MagPlex-TAG Microspheres, we demonstrate that the detection limits for these nine pathogens were as low as 102–103 CFU/mL. Furthermore, 86 clinical bronchoalveolar lavage fluid specimens were used to evaluate this method. Compared with the results of nine simplex real-time PCR reactions targeting these nine pathogens, this MPLT assay demonstrated a high diagnostic accuracy for Streptococcus pneumoniae (sensitivity, 87.5% and specificity, 100%). Furthermore, sensitivity and specificity for the other eight pathogens all attained 100% diagnostic accuracy. In addition, the consistency between MPLT and the nine real-time PCR reactions exceeded 98.8%. In conclusion, MPLT is a high-throughput, labor-saving and reliable method with high sensitivity and specificity for identifying nine respiratory pathogens responsible for LRTIs. Indeed, this assay may be a promising supplement to conventional methods used to diagnose LRTIs. PMID:28241513

  7. Single Pathogen Challenge with Agents of the Bovine Respiratory Disease Complex

    PubMed Central

    Gershwin, Laurel J.; Van Eenennaam, Alison L.; Anderson, Mark L.; McEligot, Heather A.; Toaff-Rosenstein, Rachel; Taylor, Jeremy F.; Neibergs, Holly L.; Womack, James

    2015-01-01

    Bovine respiratory disease complex (BRDC) is an important cause of mortality and morbidity in cattle; costing the dairy and beef industries millions of dollars annually, despite the use of vaccines and antibiotics. BRDC is caused by one or more of several viruses (bovine respiratory syncytial virus, bovine herpes type 1 also known as infectious bovine rhinotracheitis, and bovine viral diarrhea virus), which predispose animals to infection with one or more bacteria. These include: Pasteurella multocida, Mannheimia haemolytica, Mycoplasma bovis, and Histophilus somni. Some cattle appear to be more resistant to BRDC than others. We hypothesize that appropriate immune responses to these pathogens are subject to genetic control. To determine which genes are involved in the immune response to each of these pathogens it was first necessary to experimentally induce infection separately with each pathogen to document clinical and pathological responses in animals from which tissues were harvested for subsequent RNA sequencing. Herein these infections and animal responses are described. PMID:26571015

  8. Association of targeted multiplex PCR with resequencing microarray for the detection of multiple respiratory pathogens

    PubMed Central

    Shen, Hongwei; Zhu, Bingqing; Wang, Shulian; Mo, Haolian; Wang, Ji; Li, Jin; Zhang, Chen; Zeng, Huashu; Guan, Li; Shi, Weixian; Zhang, Yong; Ma, Xuejun

    2015-01-01

    A large number of viral and bacterial organisms are responsible for community-acquired pneumonia (CAP) which contributes to substantial burden on health management. A new resequencing microarray (RPM-IVDC1) associated with targeted multiplex PCR was recently developed and validated for multiple respiratory viruses detection and discrimination. In this study, we evaluated the capability of RPM-IVDC1 for simultaneous identification of multiple viral and bacterial organisms. The nasopharyngeal aspirates (NPAs) of 110 consecutive CAP patients, aged from 1 month to 96 years old, were collected from five distinct general hospitals in Beijing during 1-year period. The samples were subjected to the RPM-IVDC1 established protocol as compared to a real-time PCR (qRT-PCR), which was used as standard. The results of virus detection were consistent with those previously described. A total of 37 of Streptococcus pneumoniae, 14 of Haemophilus influenzae, 10 of Mycoplasma pneumoniae, two of Klebsiella pneumoniae and one of Moraxella catarrhalis were detected by RPM-IVDC1. The sensitivities and specificities were compared with those of qRT-PCR for S. pneumoniae (100, 100%, respectively), H. influenzae (92.3, 97.9%, respectively), M. pneumoniae (69.2, 99.0%, respectively), K. pneumoniae (100, 100%, respectively), and M. catarrhalis (100, 100%, respectively). Additional 22 of Streptococcus spp., 24 of Haemophilus spp. and 16 of Neisseria spp. were identified. In addition, methicillin-resistant and carbapenemases allele were also found in nine of Staphylococcus spp. and one of K. pneumoniae, respectively. These results demonstrated the capability of RPM-IVDC1 for simultaneous detection of broad-spectrum respiratory pathogens in complex backgrounds and the advantage of accessing to the actual sequences, showing great potential use of epidemic outbreak investigation. The detection results should be carefully interpreted when introducing this technique in the clinical diagnostics. PMID

  9. ATP-Binding Cassette (ABC) Transporters of the Human Respiratory Tract Pathogen, Moraxella catarrhalis: Role in Virulence

    PubMed Central

    Murphy, Timothy F; Brauer, Aimee L.; Johnson, Antoinette; Kirkham, Charmaine

    2016-01-01

    Moraxella catarrhalis is a human respiratory tract pathogen that causes otitis media (middle ear infections) in children and respiratory tract infections in adults with chronic obstructive pulmonary disease. In view of the huge global burden of disease caused by M. catarrhalis, the development of vaccines to prevent these infections and better approaches to treatment have become priorities. In previous work, we used a genome mining approach that identified three substrate binding proteins (SBPs) of ATP-binding cassette (ABC) transporters as promising candidate vaccine antigens. In the present study, we performed a comprehensive assessment of 19 SBPs of 15 ABC transporter systems in the M. catarrhalis genome by engineering knockout mutants and studying their role in assays that assess mechanisms of infection. The capacity of M. catarrhalis to survive and grow in the nutrient-limited and hostile environment of the human respiratory tract, including intracellular growth, account in part for its virulence. The results show that ABC transporters that mediate uptake of peptides, amino acids, cations and anions play important roles in pathogenesis by enabling M. catarrhalis to 1) grow in nutrient-limited conditions, 2) invade and survive in human respiratory epithelial cells and 3) persist in the lungs in a murine pulmonary clearance model. The knockout mutants of SBPs and ABC transporters showed different patterns of activity in the assay systems, supporting the conclusion that different SBPs and ABC transporters function at different stages in the pathogenesis of infection. These results indicate that ABC transporters are nutritional virulence factors, functioning to enable the survival of M catarrhalis in the diverse microenvironments of the respiratory tract. Based on the role of ABC transporters as virulence factors of M. catarrhalis, these molecules represent potential drug targets to eradicate the organism from the human respiratory tract. PMID:27391026

  10. Trends in antibiotic resistance of respiratory pathogens: an analysis and commentary on a collaborative surveillance study.

    PubMed

    Baquero, F

    1996-07-01

    The evolution of antibiotic resistance was studied among common respiratory tract pathogens in five countries of the European Union and in the USA during 1992-1993. The data obtained from a collaborative surveillance study were submitted to population analysis, to detect possible shifts in antibiotic susceptibility and, therefore, associated mechanisms of resistance. Among the emerging haemophilus influenzae phenotypes were isolates that did not correspond to the beta-lactamase negative, amino-penicillin resistant (BLNAR) phenotype, but were beta-lactamase producers showing low level ceftriaxone resistance (early extended spectrum beta-lactamases?) amoxycillin susceptible strains with low level ceftriaxone resistance (PBP modification?) and isolates with high-level fluoroquinolone resistance. Moraxella catarrhalis resistance to ceftriaxone erythromycin or fluoroquinolones was noted. The quantitative evolution of antibiotic resistance may reach saturation in some countries with a very high proportion of resistant strains, for example, Spain and France. Qualitatively, resistant strains may be selected that have broader or more effective mechanisms of resistance, particularly under the recently introduced pressure of more active antibiotics of the same family. In countries with modest levels of antibiotic resistance (UK, Germany, Italy), attention should be paid to the misuse of antibiotics with a propensity to select low-level resistant strains. In this respect, the relative prescribing of aminopenicillins and oral cephalosporins in the UK (a high ratio and low prevalence of Streptococcus pneumoniae) and resistance to penicillin in the USA (a low ratio and high prevalence of resistance) is of potential importance.

  11. Piracy of adhesins: attachment of superinfecting pathogens to respiratory cilia by secreted adhesins of Bordetella pertussis.

    PubMed

    Tuomanen, E

    1986-12-01

    Two proteins secreted by Bordetella pertussis are known to mediate adherence of these bacteria to mammalian respiratory cilia. When either ciliated cells or other pathogenic bacteria were pretreated with these adhesins, Streptococcus pneumoniae, Haemophilus influenzae, and Staphylococcus aureus acquired the ability to adhere to cilia in vitro and in vivo. Such piracy of adhesins may contribute to superinfection in mucosal diseases such as whooping cough.

  12. Characterization of Potential Surrogates for Produce Pathogens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background Escherichia coli (E. coli) is commonly used as a surrogate for pathogens in research to identify sources of agricultural contamination and to characterize how pathogens persist on plant surfaces. However, E. coli strains are highly diverse, exhibiting differences in physical, chemical and...

  13. Comparison of commercial systems for extraction of nucleic acids from DNA/RNA respiratory pathogens.

    PubMed

    Yang, Genyan; Erdman, Dean E; Kodani, Maja; Kools, John; Bowen, Michael D; Fields, Barry S

    2011-01-01

    This study compared six automated nucleic acid extraction systems and one manual kit for their ability to recover nucleic acids from human nasal wash specimens spiked with five respiratory pathogens, representing Gram-positive bacteria (Streptococcus pyogenes), Gram-negative bacteria (Legionella pneumophila), DNA viruses (adenovirus), segmented RNA viruses (human influenza virus A), and non-segmented RNA viruses (respiratory syncytial virus). The robots and kit evaluated represent major commercially available methods that are capable of simultaneous extraction of DNA and RNA from respiratory specimens, and included platforms based on magnetic-bead technology (KingFisher mL, Biorobot EZ1, easyMAG, KingFisher Flex, and MagNA Pure Compact) or glass fiber filter technology (Biorobot MDX and the manual kit Allprep). All methods yielded extracts free of cross-contamination and RT-PCR inhibition. All automated systems recovered L. pneumophila and adenovirus DNA equivalently. However, the MagNA Pure protocol demonstrated more than 4-fold higher DNA recovery from the S. pyogenes than other methods. The KingFisher mL and easyMAG protocols provided 1- to 3-log wider linearity and extracted 3- to 4-fold more RNA from the human influenza virus and respiratory syncytial virus. These findings suggest that systems differed in nucleic acid recovery, reproducibility, and linearity in a pathogen specific manner.

  14. Surveillance programme for important equine infectious respiratory pathogens in the USA.

    PubMed

    Pusterla, N; Kass, P H; Mapes, S; Johnson, C; Barnett, D C; Vaala, W; Gutierrez, C; McDaniel, R; Whitehead, B; Manning, J

    2011-07-02

    The prevalence and epidemiology of important viral (equine influenza virus [EIV], equine herpesvirus type 1 [EHV-1] and EHV-4) and bacterial (Streptococcus equi subspecies equi) respiratory pathogens shed by horses presented to equine veterinarians with upper respiratory tract signs and/or acute febrile neurological disease were studied. Veterinarians from throughout the USA were enrolled in a surveillance programme and were asked to collect blood and nasal secretions from equine cases with acute infectious upper respiratory tract disease and/or acute onset of neurological disease. A questionnaire was used to collect information pertaining to each case and its clinical signs. Samples were tested by real-time PCR for the presence of EHV-1, EHV-4, EIV and S equi subspecies equi. A total of 761 horses, mules and donkeys were enrolled in the surveillance programme over a 24-month study period. In total, 201 (26.4 per cent) index cases tested PCR-positive for one or more of the four pathogens. The highest detection rate was for EHV-4 (82 cases), followed by EIV (60 cases), S equi subspecies equi (49 cases) and EHV-1 (23 cases). There were 15 horses with double infections and one horse with a triple infection. The detection rate by PCR for the different pathogens varied with season and with the age, breed, sex and use of the animal.

  15. High-throughput Detection of Respiratory Pathogens in Animal Specimens by Nanoscale PCR.

    PubMed

    Goodman, Laura B; Anderson, Renee R; Slater, Marcia; Ortenberg, Elen; Renshaw, Randall W; Chilson, Brittany D; Laverack, Melissa A; Beeby, John S; Dubovi, Edward J; Glaser, Amy L

    2016-11-28

    Nanoliter scale real-time PCR uses spatial multiplexing to allow multiple assays to be run in parallel on a single plate without the typical drawbacks of combining reactions together. We designed and evaluated a panel based on this principle to rapidly identify the presence of common disease agents in dogs and horses with acute respiratory illness. This manuscript describes a nanoscale diagnostic PCR workflow for sample preparation, amplification, and analysis of target pathogen sequences, focusing on procedures that are different from microliter scale reactions. In the respiratory panel presented, 18 assays were each set up in triplicate, accommodating up to 48 samples per plate. A universal extraction and pre-amplification workflow was optimized for high-throughput sample preparation to accommodate multiple matrices and DNA and RNA based pathogens. Representative data are presented for one RNA target (influenza A matrix) and one DNA target (equine herpesvirus 1). The ability to quickly and accurately test for a comprehensive, syndrome-based group of pathogens is a valuable tool for improving efficiency and ergonomics of diagnostic testing and for acute respiratory disease diagnosis and management.

  16. Antimicrobial resistance trends among community-acquired respiratory tract pathogens in Greece, 2009-2012.

    PubMed

    Maraki, Sofia; Papadakis, Ioannis S

    2014-01-01

    The aim of the present study was to determine the antimicrobial resistance trends of respiratory tract pathogens isolated from patients with community-acquired respiratory tract infections (CARTIs) in Crete, Greece, over a 4-year period (2009-2012). A total of 588 community-acquired respiratory pathogens were isolated during the study period. Streptococcus pneumoniae was the most common organism responsible for 44.4% of CARTIs, followed by Haemophilus influenzae (44.2%) and Moraxella catarrhalis (11.4%). Among S. pneumoniae, the prevalence of isolates with intermediate- and high-level resistance to penicillin was 27.2% and 12.3%, respectively. Macrolide resistance slightly decreased from 29.4% over the period 2009-2010 to 28.8% over the period 2011-2012. Multiresistance was observed among 56 (54.4%) penicillin nonsusceptible isolates. A nonsignificant increase in resistance of H. influenzae isolates was noted for β -lactams, cotrimoxazole, and tetracycline. Among the 67 M. catarrhalis tested, 32 produced beta-lactamase and were resistant to ampicillin. Macrolide resistance decreased over the study period. All isolates were susceptible to amoxicillin + clavulanic acid, chloramphenicol, rifampicin, and the fluoroquinolones. Although a decreasing trend in the prevalence of resistance of the three most common pathogens involved in CARTIs was noted, continuous surveillance of antimicrobial susceptibility at the local and national level remains important, in order to guide appropriate empirical antimicrobial therapy.

  17. High-throughput Detection of Respiratory Pathogens in Animal Specimens by Nanoscale PCR

    PubMed Central

    Goodman, Laura B.; Anderson, Renee R.; Slater, Marcia; Ortenberg, Elen; Renshaw, Randall W.; Chilson, Brittany D.; Laverack, Melissa A.; Beeby, John S.; Dubovi, Edward J.; Glaser, Amy L.

    2016-01-01

    Nanoliter scale real-time PCR uses spatial multiplexing to allow multiple assays to be run in parallel on a single plate without the typical drawbacks of combining reactions together. We designed and evaluated a panel based on this principle to rapidly identify the presence of common disease agents in dogs and horses with acute respiratory illness. This manuscript describes a nanoscale diagnostic PCR workflow for sample preparation, amplification, and analysis of target pathogen sequences, focusing on procedures that are different from microliter scale reactions. In the respiratory panel presented, 18 assays were each set up in triplicate, accommodating up to 48 samples per plate. A universal extraction and pre-amplification workflow was optimized for high-throughput sample preparation to accommodate multiple matrices and DNA and RNA based pathogens. Representative data are presented for one RNA target (influenza A matrix) and one DNA target (equine herpesvirus 1). The ability to quickly and accurately test for a comprehensive, syndrome-based group of pathogens is a valuable tool for improving efficiency and ergonomics of diagnostic testing and for acute respiratory disease diagnosis and management. PMID:27929456

  18. [Adaptation potential of cardio-respiratory system in dust diseases].

    PubMed

    Serebryakov, P V; Nenenko, O I; Fedina, I N; Rakhimzyanov, A R

    2016-01-01

    The article covers results of cardio-respiratory system evaluation in workers exposed to dust, on basis of adaptation potential evaluation via calculation of functional changes index and 6 minutes' walk test with continuous assessment of blood oxygenation and heart rate. Adaptation disorders are supported by results of external respiration assessment and echo-cardiography.

  19. Identification of Upper Respiratory Tract Pathogens Using Electrochemical Detection on an Oligonucleotide Microarray

    PubMed Central

    Lodes, Michael J.; Suciu, Dominic; Wilmoth, Jodi L.; Ross, Marty; Munro, Sandra; Dix, Kim; Bernards, Karen; Stöver, Axel G.; Quintana, Miguel; Iihoshi, Naomi; Lyon, Wanda J.; Danley, David L.; McShea, Andrew

    2007-01-01

    Bacterial and viral upper respiratory infections (URI) produce highly variable clinical symptoms that cannot be used to identify the etiologic agent. Proper treatment, however, depends on correct identification of the pathogen involved as antibiotics provide little or no benefit with viral infections. Here we describe a rapid and sensitive genotyping assay and microarray for URI identification using standard amplification and hybridization techniques, with electrochemical detection (ECD) on a semiconductor-based oligonucleotide microarray. The assay was developed to detect four bacterial pathogens (Bordetella pertussis, Streptococcus pyogenes, Chlamydia pneumoniae and Mycoplasma pneumoniae) and 9 viral pathogens (adenovirus 4, coronavirus OC43, 229E and HK, influenza A and B, parainfluinza types 1, 2, and 3 and respiratory syncytial virus. This new platform forms the basis for a fully automated diagnostics system that is very flexible and can be customized to suit different or additional pathogens. Multiple probes on a flexible platform allow one to test probes empirically and then select highly reactive probes for further iterative evaluation. Because ECD uses an enzymatic reaction to create electrical signals that can be read directly from the array, there is no need for image analysis or for expensive and delicate optical scanning equipment. We show assay sensitivity and specificity that are excellent for a multiplexed format. PMID:17895966

  20. Mass gathering and globalization of respiratory pathogens during the 2013 Hajj.

    PubMed

    Memish, Z A; Assiri, A; Turkestani, A; Yezli, S; Al Masri, M; Charrel, R; Drali, T; Gaudart, J; Edouard, S; Parola, P; Gautret, P

    2015-06-01

    Every year, more than 10 million pilgrims arrive in the Kingdom of Saudi Arabia for the Hajj or Umrah. Crowding conditions lead to high rates of respiratory infections among the pilgrims, representing a significant cause of morbidity and a major cause of hospitalization. Pre- and post-Hajj nasal specimens were prospectively obtained from a paired cohort (692 pilgrims) and from nonpaired cohorts (514 arriving and 470 departing pilgrims) from 13 countries. The countries of residence included Africa (44.2%), Asia (40.2%), the United States (8.4%) and Europe (7.2%). Nasal specimens were tested for 34 respiratory pathogens using RT-PCR. A total of 80 512 PCRs were performed. The prevalence of viruses and bacteria increased, from 7.4% and 15.4% before the Hajj to 45.4% and 31.0% after the Hajj, respectively, due to the acquisition of rhinovirus, coronaviruses (229E, HKU1, OC43), influenza A H1N1, Streptococcus pneumoniae, Haemophilus influenzae and Staphylococcus aureus. We did not identify Middle East respiratory coronavirus carriage. At arrival, the prevalence of several viruses was clearly dependent on the pilgrim's country of origin. After Hajj participation, these viruses were isolated among pilgrims from all countries, with few exceptions. No significant differences were observed between paired and nonpaired cohort results. Our results strongly suggest that, given the particularly crowded conditions during the rituals, an international mass gathering such as the Hajj may contribute to the globalization of respiratory pathogens after the cross-contamination of pilgrims harbouring pathogens that easily spread among participants. Influenza and pneumococcal vaccination, face mask use and hand hygiene should be considered in the context of the Hajj.

  1. Apoptosis, Toll-like, RIG-I-like and NOD-like Receptors Are Pathways Jointly Induced by Diverse Respiratory Bacterial and Viral Pathogens.

    PubMed

    Martínez, Isidoro; Oliveros, Juan C; Cuesta, Isabel; de la Barrera, Jorge; Ausina, Vicente; Casals, Cristina; de Lorenzo, Alba; García, Ernesto; García-Fojeda, Belén; Garmendia, Junkal; González-Nicolau, Mar; Lacoma, Alicia; Menéndez, Margarita; Moranta, David; Nieto, Amelia; Ortín, Juan; Pérez-González, Alicia; Prat, Cristina; Ramos-Sevillano, Elisa; Regueiro, Verónica; Rodriguez-Frandsen, Ariel; Solís, Dolores; Yuste, José; Bengoechea, José A; Melero, José A

    2017-01-01

    Lower respiratory tract infections are among the top five leading causes of human death. Fighting these infections is therefore a world health priority. Searching for induced alterations in host gene expression shared by several relevant respiratory pathogens represents an alternative to identify new targets for wide-range host-oriented therapeutics. With this aim, alveolar macrophages were independently infected with three unrelated bacterial (Streptococcus pneumoniae, Klebsiella pneumoniae, and Staphylococcus aureus) and two dissimilar viral (respiratory syncytial virus and influenza A virus) respiratory pathogens, all of them highly relevant for human health. Cells were also activated with bacterial lipopolysaccharide (LPS) as a prototypical pathogen-associated molecular pattern. Patterns of differentially expressed cellular genes shared by the indicated pathogens were searched by microarray analysis. Most of the commonly up-regulated host genes were related to the innate immune response and/or apoptosis, with Toll-like, RIG-I-like and NOD-like receptors among the top 10 signaling pathways with over-expressed genes. These results identify new potential broad-spectrum targets to fight the important human infections caused by the bacteria and viruses studied here.

  2. Apoptosis, Toll-like, RIG-I-like and NOD-like Receptors Are Pathways Jointly Induced by Diverse Respiratory Bacterial and Viral Pathogens

    PubMed Central

    Martínez, Isidoro; Oliveros, Juan C.; Cuesta, Isabel; de la Barrera, Jorge; Ausina, Vicente; Casals, Cristina; de Lorenzo, Alba; García, Ernesto; García-Fojeda, Belén; Garmendia, Junkal; González-Nicolau, Mar; Lacoma, Alicia; Menéndez, Margarita; Moranta, David; Nieto, Amelia; Ortín, Juan; Pérez-González, Alicia; Prat, Cristina; Ramos-Sevillano, Elisa; Regueiro, Verónica; Rodriguez-Frandsen, Ariel; Solís, Dolores; Yuste, José; Bengoechea, José A.; Melero, José A.

    2017-01-01

    Lower respiratory tract infections are among the top five leading causes of human death. Fighting these infections is therefore a world health priority. Searching for induced alterations in host gene expression shared by several relevant respiratory pathogens represents an alternative to identify new targets for wide-range host-oriented therapeutics. With this aim, alveolar macrophages were independently infected with three unrelated bacterial (Streptococcus pneumoniae, Klebsiella pneumoniae, and Staphylococcus aureus) and two dissimilar viral (respiratory syncytial virus and influenza A virus) respiratory pathogens, all of them highly relevant for human health. Cells were also activated with bacterial lipopolysaccharide (LPS) as a prototypical pathogen-associated molecular pattern. Patterns of differentially expressed cellular genes shared by the indicated pathogens were searched by microarray analysis. Most of the commonly up-regulated host genes were related to the innate immune response and/or apoptosis, with Toll-like, RIG-I-like and NOD-like receptors among the top 10 signaling pathways with over-expressed genes. These results identify new potential broad-spectrum targets to fight the important human infections caused by the bacteria and viruses studied here. PMID:28298903

  3. The detection and differentiation of canine respiratory pathogens using oligonucleotide microarrays.

    PubMed

    Wang, Lih-Chiann; Kuo, Ya-Ting; Chueh, Ling-Ling; Huang, Dean; Lin, Jiunn-Horng

    2017-05-01

    Canine respiratory diseases are commonly seen in dogs along with co-infections with multiple respiratory pathogens, including viruses and bacteria. Virus infections in even vaccinated dogs were also reported. The clinical signs caused by different respiratory etiological agents are similar, which makes differential diagnosis imperative. An oligonucleotide microarray system was developed in this study. The wild type and vaccine strains of canine distemper virus (CDV), influenza virus, canine herpesvirus (CHV), Bordetella bronchiseptica and Mycoplasma cynos were detected and differentiated simultaneously on a microarray chip. The detection limit is 10, 10, 100, 50 and 50 copy numbers for CDV, influenza virus, CHV, B. bronchiseptica and M. cynos, respectively. The clinical test results of nasal swab samples showed that the microarray had remarkably better efficacy than the multiplex PCR-agarose gel method. The positive detection rate of microarray and agarose gel was 59.0% (n=33) and 41.1% (n=23) among the 56 samples, respectively. CDV vaccine strain and pathogen co-infections were further demonstrated by the microarray but not by the multiplex PCR-agarose gel. The oligonucleotide microarray provides a highly efficient diagnosis alternative that could be applied to clinical usage, greatly assisting in disease therapy and control.

  4. How Respiratory Pathogens Contribute to Lamb Mortality in a Poorly Performing Bighorn Sheep ( Ovis canadensis ) Herd.

    PubMed

    Wood, Mary E; Fox, Karen A; Jennings-Gaines, Jessica; Killion, Halcyon J; Amundson, Sierra; Miller, Michael W; Edwards, William H

    2017-01-01

    We evaluated bighorn sheep ( Ovis canadensis ) ewes and their lambs in captivity to examine the sources and roles of respiratory pathogens causing lamb mortality in a poorly performing herd. After seven consecutive years of observed December recruitments of <10%, 13 adult female bighorn sheep from the remnant Gribbles Park herd in Colorado, US were captured and transported to the Thorne-Williams Wildlife Research Center in Wyoming in March 2013. Ewes were sampled repeatedly over 16 mo. In April 2014, ewes were separated into individual pens prior to lambing. Upon death, lambs were necropsied and tested for respiratory pathogens. Six lambs developed clinical respiratory disease and one lamb was abandoned. Pathology from an additional six lambs born in 2013 was also evaluated. Mycoplasma ovipneumoniae , leukotoxigenic Mannheimia spp., leukotoxigenic Bibersteinia trehalosi , and Pasteurella multocida all contributed to lamb pneumonia. Histopathology suggested a continuum of disease, with lesions typical of pasteurellosis predominating in younger lambs and lesions typical of mycoplasmosis predominating in older lambs. Mixed pathology was observed in lambs dying between these timeframes. We suspected that all the ewes in our study were persistently infected and chronically shedding the bacteria that contributed to summer lamb mortality.

  5. Microbiological and pathological examination of fatal calf pneumonia cases induced by bacterial and viral respiratory pathogens.

    PubMed

    Szeredi, Levente; Jánosi, Szilárd; Pálfi, Vilmos

    2010-09-01

    The infectious origin of fatal cases of calf pneumonia was studied in 48 calves from 27 different herds on postmortem examination. Lung tissue samples were examined by pathological, histological, bacterial culture, virus isolation and immunohistochemical methods for the detection of viral and bacterial infections. Pneumonia was diagnosed in 47/48 cases and infectious agents were found in 40/47 (85%) of those cases. The presence of multiple respiratory pathogens in 23/40 (57.5%) cases indicated the complex origin of fatal calf pneumonia. The most important respiratory pathogens were Mannheimia-Pasteurella in 36/40 (90%) cases, followed by Arcanobacterium pyogenes in 16/40 (40%) cases, Mycoplasma bovis in 12/40 (30%) cases, and bovine respiratory syncytial virus in 4/40 (10%) cases. Histophilus somni was detected in 2/40 (5%) cases, while bovine herpesvirus-1, bovine viral diarrhoea virus and parainfluenza virus-3 were each found in 1/40 (2.5%) case. Mastadenovirus, bovine coronavirus, influenza A virus or Chlamydiaceae were not detected.

  6. Pathogens of Bovine Respiratory Disease in North American Feedlots Conferring Multidrug Resistance via Integrative Conjugative Elements

    PubMed Central

    Klima, Cassidy L.; Zaheer, Rahat; Cook, Shaun R.; Booker, Calvin W.; Hendrick, Steve

    2014-01-01

    In this study, we determined the prevalence of bovine respiratory disease (BRD)-associated viral and bacterial pathogens in cattle and characterized the genetic profiles, antimicrobial susceptibilities, and nature of antimicrobial resistance determinants in collected bacteria. Nasopharyngeal swab and lung tissue samples from 68 BRD mortalities in Alberta, Canada (n = 42), Texas (n = 6), and Nebraska (n = 20) were screened using PCR for bovine viral diarrhea virus (BVDV), bovine respiratory syncytial virus, bovine herpesvirus 1, parainfluenza type 3 virus, Mycoplasma bovis, Mannheimia haemolytica, Pasteurella multocida, and Histophilus somni. Excepting bovine herpesvirus 1, all agents were detected. M. haemolytica (91%) and BVDV (69%) were the most prevalent, with cooccurrence in 63% of the cattle. Isolates of M. haemolytica (n = 55), P. multocida (n = 8), and H. somni (n = 10) from lungs were also collected. Among M. haemolytica isolates, a clonal subpopulation (n = 8) was obtained from a Nebraskan feedlot. All three bacterial pathogens exhibited a high rate of antimicrobial resistance, with 45% exhibiting resistance to three or more antimicrobials. M. haemolytica (n = 18), P. multocida (n = 3), and H. somni (n = 3) from Texas and Nebraska possessed integrative conjugative elements (ICE) that conferred resistance for up to seven different antimicrobial classes. ICE were shown to be transferred via conjugation from P. multocida to Escherichia coli and from M. haemolytica and H. somni to P. multocida. ICE-mediated multidrug-resistant profiles of bacterial BRD pathogens could be a major detriment to many of the therapeutic antimicrobial strategies currently used to control BRD. PMID:24478472

  7. Pathogens of bovine respiratory disease in North American feedlots conferring multidrug resistance via integrative conjugative elements.

    PubMed

    Klima, Cassidy L; Zaheer, Rahat; Cook, Shaun R; Booker, Calvin W; Hendrick, Steve; Alexander, Trevor W; McAllister, Tim A

    2014-02-01

    In this study, we determined the prevalence of bovine respiratory disease (BRD)-associated viral and bacterial pathogens in cattle and characterized the genetic profiles, antimicrobial susceptibilities, and nature of antimicrobial resistance determinants in collected bacteria. Nasopharyngeal swab and lung tissue samples from 68 BRD mortalities in Alberta, Canada (n = 42), Texas (n = 6), and Nebraska (n = 20) were screened using PCR for bovine viral diarrhea virus (BVDV), bovine respiratory syncytial virus, bovine herpesvirus 1, parainfluenza type 3 virus, Mycoplasma bovis, Mannheimia haemolytica, Pasteurella multocida, and Histophilus somni. Excepting bovine herpesvirus 1, all agents were detected. M. haemolytica (91%) and BVDV (69%) were the most prevalent, with cooccurrence in 63% of the cattle. Isolates of M. haemolytica (n = 55), P. multocida (n = 8), and H. somni (n = 10) from lungs were also collected. Among M. haemolytica isolates, a clonal subpopulation (n = 8) was obtained from a Nebraskan feedlot. All three bacterial pathogens exhibited a high rate of antimicrobial resistance, with 45% exhibiting resistance to three or more antimicrobials. M. haemolytica (n = 18), P. multocida (n = 3), and H. somni (n = 3) from Texas and Nebraska possessed integrative conjugative elements (ICE) that conferred resistance for up to seven different antimicrobial classes. ICE were shown to be transferred via conjugation from P. multocida to Escherichia coli and from M. haemolytica and H. somni to P. multocida. ICE-mediated multidrug-resistant profiles of bacterial BRD pathogens could be a major detriment to many of the therapeutic antimicrobial strategies currently used to control BRD.

  8. Development of a one-run real-time PCR detection system for pathogens associated with bovine respiratory disease complex.

    PubMed

    Kishimoto, Mai; Tsuchiaka, Shinobu; Rahpaya, Sayed Samim; Hasebe, Ayako; Otsu, Keiko; Sugimura, Satoshi; Kobayashi, Suguru; Komatsu, Natsumi; Nagai, Makoto; Omatsu, Tsutomu; Naoi, Yuki; Sano, Kaori; Okazaki-Terashima, Sachiko; Oba, Mami; Katayama, Yukie; Sato, Reiichiro; Asai, Tetsuo; Mizutani, Tetsuya

    2017-03-18

    Bovine respiratory disease complex (BRDC) is frequently found in cattle worldwide. The etiology of BRDC is complicated by infections with multiple pathogens, making identification of the causal pathogen difficult. Here, we developed a detection system by applying TaqMan real-time PCR (Dembo respiratory-PCR) to screen a broad range of microbes associated with BRDC in a single run. We selected 16 bovine respiratory pathogens (bovine viral diarrhea virus, bovine coronavirus, bovine parainfluenza virus 3, bovine respiratory syncytial virus, influenza D virus, bovine rhinitis A virus, bovine rhinitis B virus, bovine herpesvirus 1, bovine adenovirus 3, bovine adenovirus 7, Mannheimia haemolytica, Pasteurella multocida, Histophilus somni, Trueperella pyogenes, Mycoplasma bovis and Ureaplasma diversum) as detection targets and designed novel specific primer-probe sets for nine of them. The assay performance was assessed using standard curves from synthesized DNA. In addition, the sensitivity of the assay was evaluated by spiking solutions extracted from nasal swabs that were negative by Dembo respiratory-PCR for nucleic acids of pathogens or synthesized DNA. All primer-probe sets showed high sensitivity. In this study, a total of 40 nasal swab samples from cattle on six farms were tested by Dembo respiratory-PCR. Dembo respiratory-PCR can be applied as a screening system with wide detection targets.

  9. Development of a one-run real-time PCR detection system for pathogens associated with bovine respiratory disease complex

    PubMed Central

    KISHIMOTO, Mai; TSUCHIAKA, Shinobu; RAHPAYA, Sayed Samim; HASEBE, Ayako; OTSU, Keiko; SUGIMURA, Satoshi; KOBAYASHI, Suguru; KOMATSU, Natsumi; NAGAI, Makoto; OMATSU, Tsutomu; NAOI, Yuki; SANO, Kaori; OKAZAKI-TERASHIMA, Sachiko; OBA, Mami; KATAYAMA, Yukie; SATO, Reiichiro; ASAI, Tetsuo; MIZUTANI, Tetsuya

    2017-01-01

    Bovine respiratory disease complex (BRDC) is frequently found in cattle worldwide. The etiology of BRDC is complicated by infections with multiple pathogens, making identification of the causal pathogen difficult. Here, we developed a detection system by applying TaqMan real-time PCR (Dembo respiratory-PCR) to screen a broad range of microbes associated with BRDC in a single run. We selected 16 bovine respiratory pathogens (bovine viral diarrhea virus, bovine coronavirus, bovine parainfluenza virus 3, bovine respiratory syncytial virus, influenza D virus, bovine rhinitis A virus, bovine rhinitis B virus, bovine herpesvirus 1, bovine adenovirus 3, bovine adenovirus 7, Mannheimia haemolytica, Pasteurella multocida, Histophilus somni, Trueperella pyogenes, Mycoplasma bovis and Ureaplasma diversum) as detection targets and designed novel specific primer-probe sets for nine of them. The assay performance was assessed using standard curves from synthesized DNA. In addition, the sensitivity of the assay was evaluated by spiking solutions extracted from nasal swabs that were negative by Dembo respiratory-PCR for nucleic acids of pathogens or synthesized DNA. All primer-probe sets showed high sensitivity. In this study, a total of 40 nasal swab samples from cattle on six farms were tested by Dembo respiratory-PCR. Dembo respiratory-PCR can be applied as a screening system with wide detection targets. PMID:28070089

  10. Evaluating the growth potential of pathogenic bacteria in water.

    PubMed

    Vital, Marius; Stucki, David; Egli, Thomas; Hammes, Frederik

    2010-10-01

    The degree to which a water sample can potentially support the growth of human pathogens was evaluated. For this purpose, a pathogen growth potential (PGP) bioassay was developed based on the principles of conventional assimilable organic carbon (AOC) determination, but using pure cultures of selected pathogenic bacteria (Escherichia coli O157, Vibrio cholerae, or Pseudomonas aeruginosa) as the inoculum. We evaluated 19 water samples collected after different treatment steps from two drinking water production plants and a wastewater treatment plant and from ozone-treated river water. Each pathogen was batch grown to stationary phase in sterile water samples, and the concentration of cells produced was measured using flow cytometry. In addition, the fraction of AOC consumed by each pathogen was estimated. Pathogen growth did not correlate with dissolved organic carbon (DOC) concentration and correlated only weakly with the concentration of AOC. Furthermore, the three pathogens never grew to the same final concentration in any water sample, and the relative ratio of the cultures to each other was unique in each sample. These results suggest that the extent of pathogen growth is affected not only by the concentration but also by the composition of AOC. Through this bioassay, PGP can be included as a parameter in water treatment system design, control, and operation. Additionally, a multilevel concept that integrates the results from the bioassay into the bigger framework of pathogen growth in water is discussed. The proposed approach provides a first step for including pathogen growth into microbial risk assessment.

  11. Metagenomics Study of Viral Pathogens in Undiagnosed Respiratory Specimens and Identification of Human Enteroviruses at a Thailand Hospital

    PubMed Central

    Zhou, Yanfei; Fernandez, Stefan; Yoon, In-Kyu; Simasathien, Sriluck; Watanaveeradej, Veerachai; Yang, Yu; Marte-Salcedo, Omely A.; Shuck-Lee, Deidra J.; Thomas, Stephen J.; Hang, Jun; Jarman, Richard G.

    2016-01-01

    Numerous pathogens cause respiratory infections with similar symptoms. Routine diagnostics detect only a limited number of pathogens, leaving a gap in respiratory illness etiology surveillance. This study evaluated next-generation sequencing for unbiased pathogen identification. Respiratory samples collected in Thailand, Philippines, Bhutan, and Nepal, that were negative by several molecular and immunofluorescence assays, underwent viral cultivation. Samples which demonstrated cytopathic effect in culture (N = 121) were extracted and tested by Luminex xTAG respiratory viral panel (RVP) assay and deep sequencing by Roche 454 FLX Titanium system. Using RVP assay, 52 (43%) samples were positive for enterovirus or rhinovirus and another three were positive for respiratory syncytial virus B, parainfluenza 4, and adenovirus. Deep sequencing confirmed the Luminex assay results and identified additional viral pathogens. Human enteroviruses, including Enterovirus A type 71 and 12 types of Enterovirus B (EV-B) were identified from a hospital in Bangkok. Phylogenetic and recombination analysis showed high correlation of VP1 gene-based phylogeny with genome-wide phylogeny and the frequent genetic exchange among EV-B viruses. The high number and diversity of enteroviruses in the hospital in Bangkok suggests prevalent existence. The metagenomic approach used in our study enabled comprehensive diagnoses of respiratory viruses. PMID:27352877

  12. Whole Genome Sequence Analysis of Pig Respiratory Bacterial Pathogens with Elevated Minimum Inhibitory Concentrations for Macrolides.

    PubMed

    Dayao, Denise Ann Estarez; Seddon, Jennifer M; Gibson, Justine S; Blackall, Patrick J; Turni, Conny

    2016-10-01

    Macrolides are often used to treat and control bacterial pathogens causing respiratory disease in pigs. This study analyzed the whole genome sequences of one clinical isolate of Actinobacillus pleuropneumoniae, Haemophilus parasuis, Pasteurella multocida, and Bordetella bronchiseptica, all isolated from Australian pigs to identify the mechanism underlying the elevated minimum inhibitory concentrations (MICs) for erythromycin, tilmicosin, or tulathromycin. The H. parasuis assembled genome had a nucleotide transition at position 2059 (A to G) in the six copies of the 23S rRNA gene. This mutation has previously been associated with macrolide resistance but this is the first reported mechanism associated with elevated macrolide MICs in H. parasuis. There was no known macrolide resistance mechanism identified in the other three bacterial genomes. However, strA and sul2, aminoglycoside and sulfonamide resistance genes, respectively, were detected in one contiguous sequence (contig 1) of A. pleuropneumoniae assembled genome. This contig was identical to plasmids previously identified in Pasteurellaceae. This study has provided one possible explanation of elevated MICs to macrolides in H. parasuis. Further studies are necessary to clarify the mechanism causing the unexplained macrolide resistance in other Australian pig respiratory pathogens including the role of efflux systems, which were detected in all analyzed genomes.

  13. Partial comparison of the NxTAG Respiratory Pathogen Panel Assay with the Luminex xTAG Respiratory Panel Fast Assay V2 and singleplex real-time polymerase chain reaction for detection of respiratory pathogens.

    PubMed

    Esposito, Susanna; Scala, Alessia; Bianchini, Sonia; Presicce, Maria Lory; Mori, Alessandro; Sciarrabba, Calogero Sathya; Fior, Giulia; Principi, Nicola

    2016-09-01

    In this study, 185 nasopharyngeal swabs were tested to compare the sensitivity and specificity of the Luminex NxTAG (NxTAG) Respiratory Pathogen Panel (RPP) Assay with those of the Luminex Respiratory Virus Panel (RVP) Fast Assay v2 and singleplex real-time polymerase chain reaction (PCR). The NxTAG Assay identified at least one infectious agent in 164 (88.7%) of the swabs. In 91 (6.2%) tests with negative results with the RVP Fast Assay v2, a virus was identified by the NxTAG (P < 0.001). With the NxTAG Assay, the detection rates were significantly higher for respiratory syncytial virus (P = 0.003), human metapneumovirus (P < 0.001), human rhinovirus/human enterovirus (P = 0.009) and human adenovirus (P < 0.001). Finally, the NxTAG Assay identified M. pneumoniae in 32 of 44 (72.7%) PCR-positive samples. However, the concordance with real-time PCR results was low for both assays. In conclusion, the results indicate that the NxTAG Assay overcomes some of the limitations of previous Luminex assays, although further studies are needed for a more complete evaluation of the new assay.

  14. Exploration of the Effectiveness of Social Distancing on Respiratory Pathogen Transmission Implicates Environmental Contributions

    DTIC Science & Technology

    2008-09-01

    al. An outbreak of acute respiratory disease caused by Mycoplasma pneumoniae and adenovirus at a federal service training academy: new implications...26] could play a crucial role in FRI epidemics at military recruit training centers and wherever new individuals are continually being introduced...socially distanced from potentially infectious individuals who were new to the group would incur rates of illness lower than those noted for groups

  15. [Potential pathogens in multiple sclerosis (MS)].

    PubMed

    Zawada, Mariola

    2012-10-22

     Multiple sclerosis is a neuroimmunological disease in which etiologic agents have not been identified yet. The etiology of MS is complex in its nature and may involve many different agents acting simultaneously or in a cascade manner leading to the development of the disease. The causes of MS development were sought among the factors associated with HLA and TCR genes and human endogenous retroviruses (HERV). Environmental factors such as bacterial, fungal and viral infections as well as potential participation of vitamin D in the pathogenesis of the disease have also been examined. The current state of knowledge concerning potential factors participating in the etiopathogenesis of multiple sclerosis has been reviewed in this paper.

  16. Storm Impacts on Potential Pathogens in Estuaries

    NASA Astrophysics Data System (ADS)

    Fries, J. Stephen; Noble, Rachel T.; Kelly, Ginger M.; Hsieh, Jennifer L.

    2007-02-01

    Estuarine and coastal environments are susceptible to a variety of changes driven by tropical storms and hurricanes. The 2005 Atlantic hurricane season impressed upon the public the devastating impacts of storms on coastal populations and the possible social and public health costs. Storm surges and subsequent flooding have the potential to redistribute water and associated contaminants, including a wide range of chemicals and microorganisms. While this impact is difficult to observe through monitoring during larger storms, smaller storms provide opportunities to observe the mechanisms responsible for contaminant and microbial transport.

  17. Biosynthesis of the respiratory toxin bongkrekic acid in the pathogenic bacterium Burkholderia gladioli.

    PubMed

    Moebius, Nadine; Ross, Claudia; Scherlach, Kirstin; Rohm, Barbara; Roth, Martin; Hertweck, Christian

    2012-09-21

    Bongkrekic acid (BA), an infamous respiratory toxin of the pathogenic bacterium Burkholderia gladioli, causes lethal intoxications when tempe bongkrek is produced with contaminated Rhizopus oligosporus cultures. Genome sequencing of B. gladioli pathovar cocovenenans unveiled the genetic basis for BA biosynthesis, and pointed to a homologous bon gene cluster in a B. gladioli strain from an infected rice plant. For functional genetics in B. gladioli λ Red recombination was established. Dissection of the modular type I polyketide synthase (a trans-AT PKS) provided insights into complex polyketide assembly. Isoprenoid-like β-branching events and a six-electron oxidation of a methyl group to a carboxylic acid give rise to the unique branched tricarboxylic fatty acid. The role of the cytochrome P450 monooxygenase, BonL, was proven by structural elucidation of deoxybongkrekic acid from a mutant.

  18. PCR based bronchoscopic detection of common respiratory pathogens in chronic cough: a case control study

    PubMed Central

    2012-01-01

    Background Viral respiratory tract infection is the most frequent cause of acute cough and is reported at onset in about one third of patients with chronic cough. Persistent infection is therefore one possible explanation for the cough reflex hypersensitivity and pulmonary inflammation reported in chronic cough patients. Methods Bronchoscopic endobronchial biopsies and bronchoalveolar lavage cell counts were obtained from ten healthy volunteers and twenty treatment resistant chronic cough patients (10 selected for lavage lymphocytosis). A screen for known respiratory pathogens was performed on biopsy tissue. Chronic cough patients also underwent cough reflex sensitivity testing using citric acid. Results There was no significant difference in incidence of infection between healthy volunteers and chronic cough patients (p = 0.115) or non-lymphocytic and lymphocytic groups (p = 0.404). BAL cell percentages were not significantly different between healthy volunteers and chronic cough patients without lymphocytosis. Lymphocytic patients however had a significantly raised percentage of lymphocytes (p < 0.01), neutrophils (p < 0.05), eosinophils (p < 0.05) and decreased macrophages (p < 0.001) verses healthy volunteers. There was no significant difference in the cough reflex sensitivity between non-lymphocytic and lymphocytic patients (p = 0.536). Conclusions This study indicates latent infection in the lung is unlikely to play an important role in chronic cough, but a role for undetected or undetectable pathogens in either the lung or a distal site could not be ruled out. Trials registration Current Controlled Trials ISRCTN62337037 & ISRCTN40147207 PMID:22978556

  19. An Epithelial Integrin Regulates the Amplitude of Protective Lung Interferon Responses against Multiple Respiratory Pathogens

    PubMed Central

    Van de Velde, Nicholas C.; Karlsson, Erik A.; Neale, Geoff; Vogel, Peter; Sharma, Shalini; Duan, Susu; Surman, Sherri L.; Jones, Bart G.; Johnson, Michael D. L.; Bosio, Catharine; Jolly, Lisa; Jenkins, R. Gisli; Hurwitz, Julia L.; Rosch, Jason W.; Sheppard, Dean; Thomas, Paul G.; Murray, Peter J.; Schultz-Cherry, Stacey

    2016-01-01

    The healthy lung maintains a steady state of immune readiness to rapidly respond to injury from invaders. Integrins are important for setting the parameters of this resting state, particularly the epithelial-restricted αVβ6 integrin, which is upregulated during injury. Once expressed, αVβ6 moderates acute lung injury (ALI) through as yet undefined molecular mechanisms. We show that the upregulation of β6 during influenza infection is involved in disease pathogenesis. β6-deficient mice (β6 KO) have increased survival during influenza infection likely due to the limited viral spread into the alveolar spaces leading to reduced ALI. Although the β6 KO have morphologically normal lungs, they harbor constitutively activated lung CD11b+ alveolar macrophages (AM) and elevated type I IFN signaling activity, which we traced to the loss of β6-activated transforming growth factor-β (TGF-β). Administration of exogenous TGF-β to β6 KO mice leads to reduced numbers of CD11b+ AMs, decreased type I IFN signaling activity and loss of the protective phenotype during influenza infection. Protection extended to other respiratory pathogens such as Sendai virus and bacterial pneumonia. Our studies demonstrate that the loss of one epithelial protein, αVβ6 integrin, can alter the lung microenvironment during both homeostasis and respiratory infection leading to reduced lung injury and improved survival. PMID:27505057

  20. The mitochondrial alternative oxidase Aox1 is needed to cope with respiratory stress but dispensable for pathogenic development in Ustilago maydis.

    PubMed

    Cárdenas-Monroy, Christian A; Pohlmann, Thomas; Piñón-Zárate, Gabriela; Matus-Ortega, Genaro; Guerra, Guadalupe; Feldbrügge, Michael; Pardo, Juan Pablo

    2017-01-01

    The mitochondrial alternative oxidase is an important enzyme that allows respiratory activity and the functioning of the Krebs cycle upon disturbance of the respiration chain. It works as a security valve in transferring excessive electrons to oxygen, thereby preventing potential damage by the generation of harmful radicals. A clear biological function, besides the stress response, has so far convincingly only been shown for plants that use the alternative oxidase to generate heat to distribute volatiles. In fungi it was described that the alternative oxidase is needed for pathogenicity. Here, we investigate expression and function of the alternative oxidase at different stages of the life cycle of the corn pathogen Ustilago maydis (Aox1). Interestingly, expression of Aox1 is specifically induced during the stationary phase suggesting a role at high cell density when nutrients become limiting. Studying deletion strains as well as overexpressing strains revealed that Aox1 is dispensable for normal growth, for cell morphology, for response to temperature stress as well as for filamentous growth and plant pathogenicity. However, during conditions eliciting respiratory stress yeast-like growth as well as hyphal growth is strongly affected. We conclude that Aox1 is dispensable for the normal biology of the fungus but specifically needed to cope with respiratory stress.

  1. The mitochondrial alternative oxidase Aox1 is needed to cope with respiratory stress but dispensable for pathogenic development in Ustilago maydis

    PubMed Central

    Piñón-Zárate, Gabriela; Matus-Ortega, Genaro; Guerra, Guadalupe; Feldbrügge, Michael; Pardo, Juan Pablo

    2017-01-01

    The mitochondrial alternative oxidase is an important enzyme that allows respiratory activity and the functioning of the Krebs cycle upon disturbance of the respiration chain. It works as a security valve in transferring excessive electrons to oxygen, thereby preventing potential damage by the generation of harmful radicals. A clear biological function, besides the stress response, has so far convincingly only been shown for plants that use the alternative oxidase to generate heat to distribute volatiles. In fungi it was described that the alternative oxidase is needed for pathogenicity. Here, we investigate expression and function of the alternative oxidase at different stages of the life cycle of the corn pathogen Ustilago maydis (Aox1). Interestingly, expression of Aox1 is specifically induced during the stationary phase suggesting a role at high cell density when nutrients become limiting. Studying deletion strains as well as overexpressing strains revealed that Aox1 is dispensable for normal growth, for cell morphology, for response to temperature stress as well as for filamentous growth and plant pathogenicity. However, during conditions eliciting respiratory stress yeast-like growth as well as hyphal growth is strongly affected. We conclude that Aox1 is dispensable for the normal biology of the fungus but specifically needed to cope with respiratory stress. PMID:28273139

  2. Pathogenic potential of Tannerella forsythia enolase.

    PubMed

    Lee, J-Y; Jung, Y-J; Jun, H-K; Choi, B-K

    2016-04-01

    Although enolases are cytosolic enzymes involved in the glycolytic pathway, they can also be secreted or expressed on the surface of a variety of eukaryotic cells and bacteria. Surface-exposed enolases of eukaryotes and bacteria can function as plasminogen receptors. Furthermore, antibodies raised against bacterial enolases can react with host enolases, suggesting molecular mimicry between bacterial and host enzymes. In this study, we analyzed an enolase of the major periodontopathogen Tannerella forsythia, which is either secreted or present on the cell surface, via matrix-assisted laser desorption ionization time-of-flight mass spectrometry and immunofluorescence, respectively. The T. forsythia enolase retained the enzymatic activity converting 2-phosphoglycerate to phosphoenolpyruvate and showed plasminogen binding and activating ability, which resulted in the degradation of fibronectin secreted from human gingival fibroblasts. In addition, it induced proinflammatory cytokine production, including interleukin-1β (IL-1β), IL-6, IL-8, and tumour necrosis factor-α (TNF-a) in the human THP-1 monocytic cell line. Taken together, our results demonstrate that T. forsythia enolase plays a role in pathogenesis in the host by plasminogen activation and proinflammatory cytokine induction, which has the potential to exaggerate inflammation in periodontitis.

  3. Vaccines against respiratory viral pathogens for use in neonates: opportunities and challenges.

    PubMed

    Alexander-Miller, Martha A

    2014-12-01

    The first six months of life reflect a time of high susceptibility to severe disease following respiratory virus infection. Although this could be improved significantly by immunization, current vaccines are not approved for use in these very young individuals. This is the result of the combined effects of poor immune responsiveness and safety concerns regarding the use of live attenuated vaccines or potent adjuvants in this population. Vaccines to effectively combat respiratory viral infection ideally would result in robust CD4(+) and CD8(+) T cell responses, as well as high-affinity Ab. Inclusion of TLR agonists or single-cycle viruses is an attractive approach for provision of signals that can act as potent stimulators of dendritic cell maturation, as well as direct activators of T and/or B cells. In this article, I discuss the challenges associated with generation of a robust immune response in neonates and the potential for adjuvants to overcome these obstacles.

  4. Bacterial Metabolism in the Host Environment: Pathogen Growth and Nutrient Assimilation in the Mammalian Upper Respiratory Tract.

    PubMed

    Armstrong, Sandra K

    2015-06-01

    Pathogens evolve in specific host niches and microenvironments that provide the physical and nutritional requirements conducive to their growth. In addition to using the host as a source of food, bacterial pathogens must avoid the immune response to their presence. The mammalian upper respiratory tract is a site that is exposed to the external environment, and is readily colonized by bacteria that live as resident flora or as pathogens. These bacteria can remain localized, descend to the lower respiratory tract, or traverse the epithelium to disseminate throughout the body. By virtue of their successful colonization of the respiratory epithelium, these bacteria obtain the nutrients needed for growth, either directly from host resources or from other microbes. This chapter describes the upper respiratory tract environment, including its tissue and mucosal structure, prokaryotic biota, and biochemical composition that would support microbial life. Neisseria meningitidis and the Bordetella species are discussed as examples of bacteria that have no known external reservoirs but have evolved to obligately colonize the mammalian upper respiratory tract.

  5. The vOTU domain of highly-pathogenic porcine reproductive and respiratory syndrome virus displays a differential substrate preference

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Arterivirus genus member Porcine reproductive and respiratory syndrome virus (PRRSV) causes an economically devastating disease that presents global concerns to the pork industry, which have been exacerbated by the emergence of a highly pathogenic PRRSV strain (HP-PRRSV) in China and Southeast Asia....

  6. Pathogenicity of three type 2 Porcine Reproductive and Respiratory Syndrome virus strains in experimentally inoculated pregnant gilts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mechanisms of reproductive failure resulting from infection with porcine reproductive and respiratory syndrome virus (PRRSv) are still poorly understood. The present study, a side-by-side evaluation of the pathogenicity of three type 2 PRRSv strains in a reproductive model, was used as a pilot study...

  7. New Epidemiological and Clinical Signatures of 18 Pathogens from Respiratory Tract Infections Based on a 5-Year Study

    PubMed Central

    Lu, Yan; Chen, Dehui; Chen, Meixin; Qiu, Shuyan; Zeng, Zhiqi; Tian, Xingui; Cui, Hong; Zhou, Rong

    2015-01-01

    Background Respiratory tract infections (RTIs) are a heavy burden on society. However, due to the complex etiology of RTIs, the clinical diagnosis, treatment, and prevention of these infections remain challenging, especially in developing countries. Methods To determine the epidemiological and clinical characteristics of 18 respiratory pathogens, we analyzed 12,502 patients with acute respiratory infections (ARIs) by performing polymerase chain reaction (PCR) on patient pharyngeal swabs. Results Samples positive for at least 1 pathogen were obtained from 48.42% of the total patients. Of these pathogen-positive patients, 17.99% were infected with more than 1 pathogen. Of the 18 pathogens analyzed, four were detected with a positive detection rate (PDR) > 5%: influenza A virus (IAV) > respiratory syncytial virus (RSV) >Mycoplasma pneumoniae (MP) > human coronavirus (HCoV). The pathogens with the 4 highest co-infection rates (CIRs) were as follows: HCoV > human bocavirus (HBoV) > enterovirus (EV) > parainfluenza virus (PIV). The overall positive detection rate (PDR) varied significantly according to patient age, the season and year of detection, and the disease subgroup, but not according to patient sex. The individual PDRs of the pathogens followed 3 types of distributions for patient sex, 4 types of distributions for patient age, 4 types of seasonal distributions, 2 types of seasonal epidemic trends, 4 types of yearly epidemic trends, and different susceptibility distributions in the disease subgroups. Additionally, the overall CIR showed significantly different distributions according to patient sex, patient age, and the disease subgroup, whereas the CIRs of individual pathogens suggested significant preference characteristics. Conclusion IAV remains the most common pathogen among the pathogens analyzed. More effort should be directed toward the prevention and control of pathogens that show a trend of increasing incidence such as HCoV, human adenovirus (ADV), and

  8. A literature review of antimicrobial resistance in Pathogens associated with bovine respiratory disease.

    PubMed

    DeDonder, K D; Apley, M D

    2015-12-01

    The objective of this paper was to perform a critical review of the literature as it pertains to the current status of antimicrobial resistance in pathogens associated with bovine respiratory disease (BRD) in beef cattle and to provide a concise yet informative narrative on the most relevant publications available. As such, the scientific literature contained in PubMed, AGRICOLA, and CAB were searched in February of 2014 for articles related to susceptibility testing of Mannheimia haemolytica, Pasteurella multocida, and Histophilus somni from cases of BRD. Titles and abstracts were read and 105 articles that were relevant to the subject of BRD antibiotic resistance were attained for further review. After the application of exclusion criterion (publications must have originated from North America, be in English, adhere to standards set forth by the Clinical and Laboratory Standards Institute, and be concerning antimicrobial resistance in BRD in beef cattle), 16 articles remained and are the focus of this publication. Due to the disparate data from the few studies that investigate susceptibility testing of BRD pathogens, a quantitative assessment or meta-analysis was not performed on the studies presented in this review. However, considering diagnostic lab data, there appears to be a clear trend of a decrease in susceptibility of the three major BRD pathogens to the antimicrobials used commonly for treatment and control of BRD. Studies performing sensitivity testing on healthy cattle report much lower resistance, but it remains unclear if this is because of a true lack of resistance mechanisms, or if the isolates do contain quiescent genes for resistance that are only phenotypically expressed following the administration of an antimicrobial for either treatment or control of BRD. Future research to address this question of genotype and phenotypic expression before and after antimicrobial administration will further advance our knowledge in this area.

  9. The Respiratory Pathogen Moraxella catarrhalis Targets Collagen for Maximal Adherence to Host Tissues

    PubMed Central

    Singh, Birendra; Alvarado-Kristensson, Maria; Johansson, Martin; Hallgren, Oskar; Westergren-Thorsson, Gunilla; Mörgelin, Matthias

    2016-01-01

    ABSTRACT Moraxella catarrhalis is a human respiratory pathogen that causes acute otitis media in children and is associated with exacerbations in patients suffering from chronic obstructive pulmonary disease (COPD). The first step in M. catarrhalis colonization is adherence to the mucosa, epithelial cells, and extracellular matrix (ECM). The objective of this study was to evaluate the role of M. catarrhalis interactions with collagens from various angles. Clinical isolates (n = 43) were tested for collagen binding, followed by a detailed analysis of protein-protein interactions using recombinantly expressed proteins. M. catarrhalis-dependent interactions with collagen produced by human lung fibroblasts and tracheal tissues were studied by utilizing confocal immunohistochemistry and high-resolution scanning electron microscopy. A mouse smoke-induced chronic obstructive pulmonary disease (COPD) model was used to estimate the adherence of M. catarrhalis in vivo. We found that all M. catarrhalis clinical isolates tested adhered to fibrillar collagen types I, II, and III and network-forming collagens IV and VI. The trimeric autotransporter adhesins ubiquitous surface protein A2 (UspA2) and UspA2H were identified as major collagen-binding receptors. M. catarrhalis wild type adhered to human tracheal tissue and collagen-producing lung fibroblasts, whereas UspA2 and UspA2H deletion mutants did not. Moreover, in the COPD mouse model, bacteria devoid of UspA2 and UspA2H had a reduced level of adherence to the respiratory tract compared to the adherence of wild-type bacteria. Our data therefore suggest that the M. catarrhalis UspA2 and UspA2H-dependent interaction with collagens is highly critical for adherence in the host and, furthermore, may play an important role in the establishment of disease. PMID:27006460

  10. Genes controlling vaccine responses and disease resistance to respiratory viral pathogens in cattle

    PubMed Central

    Glass, Elizabeth J.; Baxter, Rebecca; Leach, Richard J.; Jann, Oliver C.

    2012-01-01

    Farm animals remain at risk of endemic, exotic and newly emerging viruses. Vaccination is often promoted as the best possible solution, and yet for many pathogens, either there are no appropriate vaccines or those that are available are far from ideal. A complementary approach to disease control may be to identify genes and chromosomal regions that underlie genetic variation in disease resistance and response to vaccination. However, identification of the causal polymorphisms is not straightforward as it generally requires large numbers of animals with linked phenotypes and genotypes. Investigation of genes underlying complex traits such as resistance or response to viral pathogens requires several genetic approaches including candidate genes deduced from knowledge about the cellular pathways leading to protection or pathology, or unbiased whole genome scans using markers spread across the genome. Evidence for host genetic variation exists for a number of viral diseases in cattle including bovine respiratory disease and anecdotally, foot and mouth disease virus (FMDV). We immunised and vaccinated a cattle cross herd with a 40-mer peptide derived from FMDV and a vaccine against bovine respiratory syncytial virus (BRSV). Genetic variation has been quantified. A candidate gene approach has grouped high and low antibody and T cell responders by common motifs in the peptide binding pockets of the bovine major histocompatibility complex (BoLA) DRB3 gene. This suggests that vaccines with a minimal number of epitopes that are recognised by most cattle could be designed. Whole genome scans using microsatellite and single nucleotide polymorphism (SNP) markers has revealed many novel quantitative trait loci (QTL) and SNP markers controlling both humoral and cell-mediated immunity, some of which are in genes of known immunological relevance including the toll-like receptors (TLRs). The sequencing, assembly and annotation of livestock genomes and is continuing apace. In

  11. Potency of parenteral antimicrobials including ceftolozane/tazobactam against nosocomial respiratory tract pathogens: considerations for empiric and directed therapy

    PubMed Central

    Sutherland, Christina A.

    2017-01-01

    Background Empiric therapy decisions are predicated on knowledge of both the epidemiology and antimicrobial susceptibility of the probable infecting pathogen(s). The objective of this study was to evaluate the microbial distribution and phenotypic profiles of nosocomial respiratory isolates collected from multiple US hospitals and assess the clinical utility of various monotherapy and combination regimens. Methods Hospitals provided consecutive non-duplicate adult inpatients Gram-negative nosocomial respiratory isolates from cultures received ≥48 h after hospital admission. Minimum inhibitory concentrations (MICs) for 12 antimicrobials were determined using broth microdilution methods. An antibiogram was constructed for monotherapy regimens as well as combinations inclusive of either tobramycin (TOB) or ciprofloxacin (CIP). Results Six hospitals provided 518 nosocomial respiratory isolates. P. aeruginosa (PSA) comprised 28% of the population followed by Klebsiella pneumoniae (13%), Enterobacter spp. (13%), S. maltophilia (9%), S. marcesens (6%), A. baumannii (6%), and others (18%). When considering monotherapy for the Enterobacteriaceae & PSA ceftolozane/tazobactam (C/T) provided the highest (87%) percent susceptibility (%S) followed by meropenem (MEM), CIP, cefepime (FEP), ceftazidime (CAZ) and piperacillin-tazobactam (TZP) at 71–85%S. The addition of TOB > CIP improved the probability that the antimicrobial combination would provide ≥1 active agent. Conclusions PSA was the predominant nosocomial respiratory pathogen; however, the Enterobacteriaceae comprised an additional 53% in this survey. When considering empiric β-lactam monotherapy therapy for the entire spectrum of pathogens C/T provided the highest (78%) %S followed by MEM, FEP and TZP. The addition of either TOB > CIP to these β-lactams enhances the likelihood that an active agent would be selected when considering empirical therapy choices for nosocomial respiratory tract infections. PMID

  12. Comparative Methylome Analysis of the Occasional Ruminant Respiratory Pathogen Bibersteinia trehalosi

    PubMed Central

    Smith, Timothy P. L.; Blom, Jochen; Roberts, Richard J.

    2016-01-01

    We examined and compared both the methylomes and the modification-related gene content of four sequenced strains of Bibersteinia trehalosi isolated from the nasopharyngeal tracts of Nebraska cattle with symptoms of bovine respiratory disease complex. The methylation patterns and the encoded DNA methyltransferase (MTase) gene sets were different between each strain, with the only common pattern being that of Dam (GATC). Among the observed patterns were three novel motifs attributable to Type I restriction-modification systems. In some cases the differences in methylation patterns corresponded to the gain or loss of MTase genes, or to recombination at target recognition domains that resulted in changes of enzyme specificity. However, in other cases the differences could be attributed to differential expression of the same MTase gene across strains. The most obvious regulatory mechanism responsible for these differences was slipped strand mispairing within short sequence repeat regions. The combined action of these evolutionary forces allows for alteration of different parts of the methylome at different time scales. We hypothesize that pleiotropic transcriptional modulation resulting from the observed methylomic changes may be involved with the switch between the commensal and pathogenic states of this common member of ruminant microflora. PMID:27556252

  13. Pathogenic potential of novel Chlamydiae and diagnostic approaches to infections due to these obligate intracellular bacteria.

    PubMed

    Corsaro, Daniele; Greub, Gilbert

    2006-04-01

    Novel chlamydiae are newly recognized members of the phylum Chlamydiales that are only distantly related to the classic Chlamydiaceae, i.e., Chlamydia and Chlamydophila species. They also exhibit an obligate biphasic intracellular life cycle within eukaryote host cells. Some of these new chlamydiae are currently considered potential emerging human and/or animal pathogens. Parachlamydia acanthamoebae and Simkania negevensis are both emerging respiratory human pathogens, Waddlia chondrophila could be a novel abortigenic bovine agent, and Piscichlamydia salmonis has recently been identified as an agent of the gill epitheliocystis in the Atlantic salmon. Fritschea spp. and Rhabdochlamydia spp. seem to be confined to arthropods, but some evidence for human exposure exists. In this review, we first summarize the data supporting a pathogenic potential of the novel chlamydiae for humans and other vertebrates and the interactions that most of these chlamydiae have with free-living amoebae. We then review the diagnostic approaches to infections potentially due to the novel chlamydiae, especially focusing on the currently available PCR-based protocols, mammalian cell culture, the amoebal coculture system, and serology.

  14. Nasal colonization by four potential respiratory bacteria in healthy children attending kindergarten or elementary school in Seoul, Korea.

    PubMed

    Bae, Songmee; Yu, Jae-Yon; Lee, Kwangjun; Lee, Sunhwa; Park, Bohyun; Kang, Yeonho

    2012-05-01

    A longitudinal analysis was carried out of the colonization by four potential respiratory pathogens - Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis and Staphylococcus aureus - in 165 healthy children (aged 3-7 years) attending three kindergartens and 417 healthy children (aged 7-10 years) attending an elementary school in Seoul, Korea, by four consecutive examinations over 1 year. The prevalence of nasal carriers of one or more of four bacteria was found to be higher in younger children (≤7 years) (mean 68.6%) than that in older children (mean 46.8%). The mean rates of nasal carriage of Strep. pneumoniae, H. influenzae, M. catarrhalis and Staph. aureus were 16.8, 18.9, 20.2 and 18.2%, respectively. Colonization by Strep. pneumoniae, H. influenzae and M. catarrhalis was higher in pre-school children (28.6, 32.4 and 35.0%, respectively) than in school children (12.2, 13.6 and 14.3%, respectively). Carriage trends differed with age, with Strep. pneumoniae, H. influenzae and M. catarrhalis colonization decreasing with age but Staph. aureus colonization increasing. Positive associations of co-occurrence between Strep. pneumoniae, H. influenzae and M. catarrhalis were evident, with a significant negative association evident between Staph. aureus and the other three bacteria. A better understanding of the colonization and interaction of potential respiratory pathogens may be important for predicting changes in bacterial ecology and for designing control strategies that target bacterial colonization in upper respiratory tract infections.

  15. Biomarkers of acute respiratory allergen exposure: Screening for sensitization potential

    SciTech Connect

    Pucheu-Haston, Cherie M.; Copeland, Lisa B.; Vallanat, Beena; Boykin, Elizabeth; Ward, Marsha D.W.

    2010-04-15

    Effective hazard screening will require the development of high-throughput or in vitro assays for the identification of potential sensitizers. The goal of this preliminary study was to identify potential biomarkers that differentiate the response to allergens vs non-allergens following an acute exposure in naive individuals. Female BALB/c mice received a single intratracheal aspiration exposure to Metarhizium anisopliae crude antigen (MACA) or bovine serum albumin (BSA) in Hank's Balanced Salt Solution (HBSS) or HBSS alone. Mice were terminated after 1, 3, 6, 12, 18 and 24 h. Bronchoalveolar lavage fluid (BALF) was evaluated to determine total and differential cellularity, total protein concentration and LDH activity. RNA was isolated from lung tissue for microarray analysis and qRT-PCR. MACA administration induced a rapid increase in BALF neutrophils, lymphocytes, eosinophils and total protein compared to BSA or HBSS. Microarray analysis demonstrated differential expression of genes involved in cytokine production, signaling, inflammatory cell recruitment, adhesion and activation in 3 and 12 h MACA-treated samples compared to BSA or HBSS. Further analyses allowed identification of approx 100 candidate biomarker genes. Eleven genes were selected for further assessment by qRT-PCR. Of these, 6 demonstrated persistently increased expression (Ccl17, Ccl22, Ccl7, Cxcl10, Cxcl2, Saa1), while C3ar1 increased from 6-24 h. In conclusion, a single respiratory exposure of mice to an allergenic mold extract induces an inflammatory response which is distinct in phenotype and gene transcription from the response to a control protein. Further validation of these biomarkers with additional allergens and irritants is needed. These biomarkers may facilitate improvements in screening methods.

  16. CRISPR Content Correlates with the Pathogenic Potential of Escherichia coli.

    PubMed

    García-Gutiérrez, Enriqueta; Almendros, Cristóbal; Mojica, Francisco J M; Guzmán, Noemí M; García-Martínez, Jesús

    2015-01-01

    Guide RNA molecules (crRNA) produced from clustered regularly interspaced short palindromic repeat (CRISPR) arrays, altogether with effector proteins (Cas) encoded by cognate cas (CRISPR associated) genes, mount an interference mechanism (CRISPR-Cas) that limits acquisition of foreign DNA in Bacteria and Archaea. The specificity of this action is provided by the repeat intervening spacer carried in the crRNA, which upon hybridization with complementary sequences enables their degradation by a Cas endonuclease. Moreover, CRISPR arrays are dynamic landscapes that may gain new spacers from infecting elements or lose them for example during genome replication. Thus, the spacer content of a strain determines the diversity of sequences that can be targeted by the corresponding CRISPR-Cas system reflecting its functionality. Most Escherichia coli strains possess either type I-E or I-F CRISPR-Cas systems. To evaluate their impact on the pathogenicity of the species, we inferred the pathotype and pathogenic potential of 126 strains of this and other closely related species and analyzed their repeat content. Our results revealed a negative correlation between the number of I-E CRISPR units in this system and the presence of pathogenicity traits: the median number of repeats was 2.5-fold higher for commensal isolates (with 29.5 units, range 0-53) than for pathogenic ones (12.0, range 0-42). Moreover, the higher the number of virulence factors within a strain, the lower the repeat content. Additionally, pathogenic strains of distinct ecological niches (i.e., intestinal or extraintestinal) differ in repeat counts. Altogether, these findings support an evolutionary connection between CRISPR and pathogenicity in E. coli.

  17. Bioactive potential of Streptomyces against fish and shellfish pathogens

    PubMed Central

    Selvakumar, D; Arun, K; Suguna, S; Kumar, D; Dhevendaran, K

    2010-01-01

    Background and Objectives In the present study, isolation of Streptomyces associated with marine sponges and its bioactive potential against fish and shellfish pathogens were assessed. The Streptomyces sp. were isolated from the marine sponges namely Callyspongia diffusa, Mycale mytilorum, Tedania anhelans and Dysidea fragilis collected from Vizhinjam port, situated in the South-West coast of India. Materials and Methods The Streptomyces associated with marine sponges were isolated using specific ISP media. The isolates of Streptomyces were characterized for their colony characteristics, morphological properties, physiological and biochemical properties and were tentatively identified. The strains were cultivated on a lab scale level as shake-flask cultures and the crude extracts of the bioactive compounds obtained with ethyl acetate were screened biologically and chemically. By biological screening, the extracts were analyzed for their activity against fish and shellfish pathogens namely Aeromonas hydrophila, Serratia sp. and Vibrio spp, using the disk and agar-well diffusion bioassay method, while by chemical screening the crude culture extracts were analyzed by TLC and UV–Vis spectrophotometer. Results Ninety-four isolates were found to be associated with marine sponges, among them only seven strains showed antagonism against fish and shellfish pathogens. Analysis of morphological, physiological and biochemical characteristics suggested that these strains belonged to the genus Streptomyces. The initial screening of the isolates by spot inoculation method exhibited antibacterial activity against Aeromonas hydrophila. In-vitro screening of the submerge culture extracts showed positive inhibition against the fish and shellfish pathogens namely Aeromonas hydrophila, Serratia sp. and Vibrio spp. The screening of bioactive compounds confirmed the production of polyene substances by UV spectrum, which resulted in absorbance peaks ranging from 225 to 245 nm and TLC

  18. Antibacterial activity of carbapenems against clinical isolates of respiratory bacterial pathogens in the northeastern region of Japan in 2007.

    PubMed

    Gomi, Kazunori; Fujimura, Shigeru; Fuse, Katsuhiro; Takane, Hidenari; Nakano, Yoshihisa; Kariya, Yasuko; Kikuchi, Toshiaki; Kurokawa, Iku; Tokue, Yutaka; Watanabe, Akira

    2011-04-01

    As the increasing prevalence of resistant strains of respiratory bacterial pathogens has recently been reported, continuous monitoring of the susceptibility of clinical isolates to antibacterial agents is important. We performed a surveillance study focusing on the susceptibility of major respiratory bacterial pathogens in the northeastern region of Japan to carbapenems and control drugs. A total of 168 bacterial strains isolated from patients with respiratory tract infections in 2007 were collected and the minimum inhibitory concentration (MIC) determined. MIC data were subjected to pharmacokinetic/pharmacodynamic analysis with Monte Carlo simulation to calculate the probability of achieving the target of time above MIC with each carbapenem. All Moraxella catarrhalis, Streptococcus pneumoniae, and methicillin-sensitive Staphylococcus aureus isolates were susceptible to carbapenems. Despite the increasing prevalence of β-lactamase-nonproducing ampicillin-resistant strains, all Haemophilus influenzae isolates were susceptible to meropenem. For Pseudomonas aeruginosa, the susceptibility rates for meropenem and biapenem were 76.7%, and the highest probability of achieving pharmacodynamic target (40% of the time above MIC) was obtained with meropenem 0.5 g three times daily as a 4-h infusion (89.4%), followed by meropenem 0.5 g four times daily as a 1-h infusion (88.4%). Carbapenems have retained their position as key drugs for severe respiratory tract infections.

  19. A multiplexed reverse transcriptase PCR assay for identification of viral respiratory pathogens at point-of-care

    SciTech Connect

    Letant, S E; .Ortiz, J I; Tammero, L; Birch, J M; Derlet, R W; Cohen, S; Manning, D; McBride, M T

    2007-04-11

    We have developed a nucleic acid-based assay that is rapid, sensitive, specific, and can be used for the simultaneous detection of 5 common human respiratory pathogens including influenza A, influenza B, parainfluenza type 1 and 3, respiratory syncytial virus, and adenovirus group B, C, and E. Typically, diagnosis on an un-extracted clinical sample can be provided in less than 3 hours, including sample collection, preparation, and processing, as well as data analysis. Such a multiplexed panel would enable rapid broad-spectrum pathogen testing on nasal swabs, and therefore allow implementation of infection control measures, and timely administration of antiviral therapies. This article presents a summary of the assay performance in terms of sensitivity and specificity. Limits of detection are provided for each targeted respiratory pathogen, and result comparisons are performed on clinical samples, our goal being to compare the sensitivity and specificity of the multiplexed assay to the combination of immunofluorescence and shell vial culture currently implemented at the UCDMC hospital. Overall, the use of the multiplexed RT-PCR assay reduced the rate of false negatives by 4% and reduced the rate of false positives by up to 10%. The assay correctly identified 99.3% of the clinical negatives, 97% of adenovirus, 95% of RSV, 92% of influenza B, and 77% of influenza A without any extraction performed on the clinical samples. The data also showed that extraction will be needed for parainfluenza virus, which was only identified correctly 24% of the time on un-extracted samples.

  20. The water environment as a source of potentially pathogenic mycobacteria.

    PubMed

    Makovcova, Jitka; Slany, Michal; Babak, Vladimir; Slana, Iva; Kralik, Petr

    2014-06-01

    Nontuberculous mycobacteria (NTM) are ubiquitous organisms of a wide variety of environmental reservoirs, including natural and municipal water, soil, aerosols, protozoans, animals and humans. Several of these species are potential pathogens which affect human health. The aim of this study was to determine the occurrence of NTM in the water environment. Samples were taken from 13 water-related facilities including fish ponds, storage ponds, drinking water reservoirs and an experimental recirculation system. Altogether, 396 samples of water, sediment and aquatic plants were collected and analysed. All samples were examined using conventional culture methods. Suspected microbial isolates were subjected to polymerase chain reaction analysis and identified using partial sequence analysis of the 16S rDNA gene. The culture revealed 94/396 samples (23.7%) that contained mycobacteria. Among known NTM we identified potentially pathogenic mycobacteria isolated from the fresh water environment for the first time: Mycobacterium asiaticum, M. chimaera, M. interjectum, M. kumamotonense, M. lentiflavum, M. montefiorense, M. nebraskense, M. paraffinicum and M. simiae. Epidemiologic studies suggest that the natural water environment is the principal source of human exposure. Our results indicate that besides the well-known potentially pathogenic mycobacteria it is important to observe occurrence, proliferation and persistence of newly discovered mycobacterial species.

  1. Serologic survey for pathogens potentially affecting pronghorn (Antilocapra americana) fawn recruitment in Arizona, USA.

    PubMed

    Dubay, Shelli A; Noon, Ted H; deVos, James C; Ockenfels, Richard A

    2006-10-01

    During the 1990s, pronghorn (Antilocapra americana) populations declined in Arizona, USA. To investigate potential causes of decline, we collected blood samples from hunter-harvested male pronghorn from 2001 to 2003 on four Arizona sites. Sera were tested for antibody to parainfluenza virus type 3 (PI3), bovine viral diarrhea virus, infectious bovine rhinotracheitis virus, bovine respiratory syncytial virus, epizootic hemorrhagic disease virus (EHDV), bluetongue virus (BTV), and Chlamydia psittaci. Antibody against PI3 was found in 33% of the samples, whereas antibody against BTV/EHDV was found in 77%. Antibodies to other pathogens were found at low prevalence rates. Although pronghorn decline in Arizona is probably not directly related to disease, potential reproductive effects of BTV/EHDV and PI3 infection on pronghorn in Arizona merit further study.

  2. Pathogenesis of highly pathogenic porcine reproductive and respiratory syndrome virus in Chinese Tibetan swine.

    PubMed

    Fan, Baochao; Zhang, Hongjian; Bai, Juan; Liu, Xing; Li, Yufeng; Wang, Xianwei; Jiang, Ping

    2016-10-01

    Highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) was first characterized in 2006 in China, and it causes great economic losses to the Chinese swine production industry. A China Landrace pig, the Tibetan pig, which has striking phenotypic and physiological differences from lowland pigs, is mainly distributed in the Tibetan highlands of China. The susceptibility of the Tibetan pig to HP-PRRSV has not been reported. In this study, 15 4-week-old Tibetan piglets were divided into three groups, and their susceptibility to HP-PRRSV was examined in the highland region. Five pigs in group 1 were inoculated intranasally with HP-PRRSV strain BB0907. At 2days post-inoculation, five other pigs were introduced into this group and then removed to a separated room to serve as contact group 2. Meanwhile, five pigs in group 3 were mock infected and used as controls. The results showed that the pigs in the inoculated and contact groups showed high fevers and clear clinical signs, including depression, anorexia, lethargy, sticky eye secretions, and hind limb paralysis, with high mortality. The main symptom was interstitial pneumonia. Viremia appeared on days 4 to 14 post-infection. HP-PRRSV infection resulted in inflammatory responses within the first week of infection, as evidenced by the expression of tumor necrosis factor alpha, interleukin (IL)-1β, IL-6, and IL-10. All the data indicate that the Tibetan pig is susceptible to HP-PRRSV infection. Thus, it is necessary to investigate and prevent PRRSV infections in the highland region in China.

  3. Bacterial and viral pathogen spectra of acute respiratory infections in under-5 children in hospital settings in Dhaka city

    PubMed Central

    Bhuyan, Golam Sarower; Hossain, Mohammad Amir; Sarker, Suprovath Kumar; Rahat, Asifuzzaman; Islam, Md Tarikul; Haque, Tanjina Noor; Begum, Noorjahan; Qadri, Syeda Kashfi; Muraduzzaman, A. K. M.; Islam, Nafisa Nawal; Islam, Mohammad Sazzadul; Sultana, Nusrat; Jony, Manjur Hossain Khan; Khanam, Farhana; Mowla, Golam; Matin, Abdul; Begum, Firoza; Shirin, Tahmina; Ahmed, Dilruba; Saha, Narayan; Qadri, Firdausi

    2017-01-01

    The study aimed to examine for the first time the spectra of viral and bacterial pathogens along with the antibiotic susceptibility of the isolated bacteria in under-5 children with acute respiratory infections (ARIs) in hospital settings of Dhaka, Bangladesh. Nasal swabs were collected from 200 under-five children hospitalized with clinical signs of ARIs. Nasal swabs from 30 asymptomatic children were also collected. Screening of viral pathogens targeted ten respiratory viruses using RT-qPCR. Bacterial pathogens were identified by bacteriological culture methods and antimicrobial susceptibility of the isolates was determined following CLSI guidelines. About 82.5% (n = 165) of specimens were positive for pathogens. Of 165 infected cases, 3% (n = 6) had only single bacterial pathogens, whereas 43.5% (n = 87) cases had only single viral pathogens. The remaining 36% (n = 72) cases had coinfections. In symptomatic cases, human rhinovirus was detected as the predominant virus (31.5%), followed by RSV (31%), HMPV (13%), HBoV (11%), HPIV-3 (10.5%), and adenovirus (7%). Streptococcus pneumoniae was the most frequently isolated bacterial pathogen (9%), whereas Klebsiella pneumaniae, Streptococcus spp., Enterobacter agglomerans, and Haemophilus influenzae were 5.5%, 5%, 2%, and 1.5%, respectively. Of 15 multidrug-resistant bacteria, a Klebsiella pneumoniae isolate and an Enterobacter agglomerans isolate exhibited resistance against more than 10 different antibiotics. Both ARI incidence and predominant pathogen detection rates were higher during post-monsoon and winter, peaking in September. Pathogen detection rates and coinfection incidence in less than 1-year group were significantly higher (P = 0.0034 and 0.049, respectively) than in 1–5 years age group. Pathogen detection rate (43%) in asymptomatic cases was significantly lower compared to symptomatic group (P<0.0001). Human rhinovirus, HPIV-3, adenovirus, Streptococcus pneumonia, and Klebsiella pneumaniae had

  4. Distribution of Indigenous Bacterial Pathogens and Potential Pathogens Associated with Roof-Harvested Rainwater

    PubMed Central

    Dobrowsky, P. H.; De Kwaadsteniet, M.; Cloete, T. E.

    2014-01-01

    The harvesting of rainwater is gaining acceptance among many governmental authorities in countries such as Australia, Germany, and South Africa, among others. However, conflicting reports on the microbial quality of harvested rainwater have been published. To monitor the presence of potential pathogenic bacteria during high-rainfall periods, rainwater from 29 rainwater tanks was sampled on four occasions (during June and August 2012) in a sustainable housing project in Kleinmond, South Africa. This resulted in the collection of 116 harvested rainwater samples in total throughout the sampling period. The identities of the dominant, indigenous, presumptive pathogenic isolates obtained from the rainwater samples throughout the sampling period were confirmed through universal 16S rRNA PCR, and the results revealed that Pseudomonas (19% of samples) was the dominant genus isolated, followed by Aeromonas (16%), Klebsiella (11%), and Enterobacter (9%). PCR assays employing genus-specific primers also confirmed the presence of Aeromonas spp. (16%), Klebsiella spp. (47%), Legionella spp. (73%), Pseudomonas spp. (13%), Salmonella spp. (6%), Shigella spp. (27%), and Yersinia spp. (28%) in the harvested rainwater samples. In addition, on one sampling occasion, Giardia spp. were detected in 25% of the eight tank water samples analyzed. This study highlights the diverse array of pathogenic bacteria that persist in harvested rainwater during high-rainfall periods. The consumption of untreated harvested rainwater could thus pose a potential significant health threat to consumers, especially children and immunocompromised individuals, and it is recommended that harvested rainwater be treated for safe usage as an alternative water source. PMID:24487540

  5. Development of a bead-based suspension array for the detection of pathogens in acute respiratory tract infections

    PubMed Central

    Li, Hong-Ru; Zhang, Wei; Hua, Zhi-Dan; Lin, Xiao-Hong; Lin, Meng-Qing; Huang, Wen-Sen; Huang, Li-Ping; Yu, Xiao-Li; Xu, Neng-Luan; Lin, Ming; Xie, Bao-Song; Shen, Xiao-Na; Xie, Jian-Feng; Wang, Yi; Huang, Meng; Wu, Yan-An; Hu, Xin-Lan

    2016-01-01

    We developed a high-throughput bead-based suspension array for simultaneous detection of 20 respiratory tract pathogens in clinical specimens. Pathogen-specific genes were amplified and hybridized to probes coupled to carboxyl-encoded microspheres. Fluorescence intensities generated via the binding of phycoerythrin-conjugated streptavidin with biotin-labeled targets were measured by the Luminex 100 bead-based suspension array system. The bead-based suspension array detected bacteria in a significantly higher number of samples compared to the conventional culture. There was no significant difference in the detection rate of atypical pathogensatypical pathogens or viruses between the bead-based suspension array and real-time PCR. This technology can play a significant role in screening patients with pneumonia. PMID:27190247

  6. Prevalence of upper respiratory pathogens in four management models for unowned cats in the Southeast United States.

    PubMed

    McManus, C M; Levy, J K; Andersen, L A; McGorray, S P; Leutenegger, C M; Gray, L K; Hilligas, J; Tucker, S J

    2014-08-01

    Upper respiratory infection (URI) is a pervasive problem in cats and impacts the capacity and cost of sheltering programs. This study determined the pattern of respiratory pathogens in cats with and without clinical signs of URI in four different models for managing unowned cats, namely, (1) short-term animal shelters (STS), (2) long-term sanctuaries (LTS), (3) home-based foster care programs (FCP), and (4) trap-neuter-return programs for community cats (TNR). Conjunctival and oropharyngeal swabs from 543 cats, approximately half of which showed clinical signs of URI, were tested for feline herpes virus-1 (FHV), feline calicivirus (FCV), Chlamydia felis, Bordetella bronchiseptica, Mycoplasma felis, and canine influenza virus by real-time PCR. FHV (59%, 41%) and B. bronchiseptica (33%, 24%) were more prevalent in both clinically affected and nonclinical cats, respectively, in STS than other management models. FCV (67%, 51%) and M. felis (84%, 86%) were more prevalent in LTS than any other management model. Clinically affected cats in FCP were more likely to carry FHV (23%, 6%), C. felis (24%, 10%), or M. felis (58%, 38%) than were nonclinical cats. Clinically affected cats in TNR were more likely to carry FCV (55%, 36%) or C. felis (23%, 4%) than were nonclinical cats. The prevalence of individual pathogens varied between different management models, but the majority of the cats in each model carried one or more respiratory pathogens regardless of clinical signs. Both confined and free-roaming cats are at risk of developing infectious respiratory disease and their health should be protected by strategic vaccination, appropriate antibiotic therapy, effective biosecurity, feline stress mitigation, and alternatives to high-density confinement.

  7. Biomarkers of Acute Respiratory Allergen Exposure: Screening For Sensitization Potential

    EPA Science Inventory

    Rationale: An in vitro assay to identify respiratory sensitizers will provide a rapid screen and reduce animal use. The study goal was to identify biomarkers that differentiate allergen versus non-allergen responses following an acute exposure. Methods: Female BALB/c mice rec...

  8. REVIEW: ASSESSING THE POTENTIAL TO INDUCE RESPIRATORY HYPERSENSITIVITY

    EPA Science Inventory

    The respiratory tract has been long recognized as an important target organ in the safety assessment of drugs and chemicals, as well as protein- or peptide-based products. Indeed, acute and repeat dose inhalation studies have been an important part of guideline studies throughou...

  9. Epidemiology of Pathogen-Specific Respiratory Infections Among Three US Populations

    DTIC Science & Technology

    2014-12-30

    vaccines and treatments. Introduction Acute respiratory infections make up a huge proportion of disease burden in the United States and globally...establish baselines of infection, identify outbreaks, and help prioritize the development of new vaccines and future treatments. Epidemiology of Respiratory...density barracks. During the first week of training, recruits receive a series of vaccinations , including influenza (seasonally) and adenovirus. Most

  10. A Network Integration Approach to Predict Conserved Regulators Related to Pathogenicity of Influenza and SARS-CoV Respiratory Viruses

    SciTech Connect

    Mitchell, Hugh D.; Eisfeld, Amie J.; Sims, Amy; McDermott, Jason E.; Matzke, Melissa M.; Webb-Robertson, Bobbie-Jo M.; Tilton, Susan C.; Tchitchek, Nicholas; Josset, Laurence; Li, Chengjun; Ellis, Amy L.; Chang, Jean H.; Heegel, Robert A.; Luna, Maria L.; Schepmoes, Athena A.; Shukla, Anil K.; Metz, Thomas O.; Neumann, Gabriele; Benecke, Arndt; Smith, Richard D.; Baric, Ralph; Kawaoka, Yoshihiro; Katze, Michael G.; Waters, Katrina M.

    2013-07-25

    Respiratory infections stemming from influenza viruses and the Severe Acute Respiratory Syndrome corona virus (SARS-CoV) represent a serious public health threat as emerging pandemics. Despite efforts to identify the critical interactions of these viruses with host machinery, the key regulatory events that lead to disease pathology remain poorly targeted with therapeutics. Here we implement an integrated network interrogation approach, in which proteome and transcriptome datasets from infection of both viruses in human lung epithelial cells are utilized to predict regulatory genes involved in the host response. We take advantage of a novel “crowd-based” approach to identify and combine ranking metrics that isolate genes/proteins likely related to the pathogenicity of SARS-CoV and influenza virus. Subsequently, a multivariate regression model is used to compare predicted lung epithelial regulatory influences with data derived from other respiratory virus infection models. We predicted a small set of regulatory factors with conserved behavior for consideration as important components of viral pathogenesis that might also serve as therapeutic targets for intervention. Our results demonstrate the utility of integrating diverse ‘omic datasets to predict and prioritize regulatory features conserved across multiple pathogen infection models.

  11. Human serum activity of telithromycin, azithromycin and amoxicillin/clavulanate against common aerobic and anaerobic respiratory pathogens.

    PubMed

    Stein, Gary E; Schooley, Sharon; Tyrrell, Kerin L; Citron, Diane M; Goldstein, Ellie J C

    2007-01-01

    Telithromycin is a new ketolide antimicrobial with a good in vitro activity against both aerobic and anaerobic respiratory pathogens. In this study, we evaluated the antibacterial activity over time of telithromycin (800mg), azithromycin (500mg), and amoxicillin/clavulanate (875/125mg) in serum following single oral doses of these agents to 10 healthy subjects. Inhibitory and bactericidal titers were determined at 2, 6, 12, and 24h after each dose and the median titer was used to determine antibacterial activity. Against two azithromycin-resistant strains of Streptococcus pneumoniae, both telithromycin (MIC=0.25 and 0.5 microg/mL) and amoxicillin/clavulanate exhibited inhibitory and cidal activity for at least 6h. All three antibiotics provided prolonged (>or=12h) inhibitory activity against strains of Hemophilus influenzae (telithromycin MIC=4.0 microg/ml). Both telithromycin and amoxicillin/clavulanate exhibited rapid and prolonged inhibitory activity (>or=12h) against each of the anaerobes studied (Finegoldia [Peptostreptococcus] magna Peptostreptococcus micros, Prevotella bivia, and Prevotella melaninogenica). Moreover, both agents provided bactericidal activity against both Prevotella species. In this ex vivo pharmacodynamic study, we found that telithromycin provided rapid and prolonged antibacterial activity in serum against macrolide-resistant strains of S. pneumoniae, beta-lactamase-positive and -negative strains of H. influenzae, and common respiratory anaerobic pathogens. These findings suggest that telithromycin could have clinical utility in the treatment of community-acquired mixed aerobic-anaerobic respiratory tract infections, including chronic sinusitis and aspiration pneumonia.

  12. A Network Integration Approach to Predict Conserved Regulators Related to Pathogenicity of Influenza and SARS-CoV Respiratory Viruses

    PubMed Central

    Mitchell, Hugh D.; Eisfeld, Amie J.; Sims, Amy C.; McDermott, Jason E.; Matzke, Melissa M.; Webb-Robertson, Bobbi-Jo M.; Tilton, Susan C.; Tchitchek, Nicolas; Josset, Laurence; Li, Chengjun; Ellis, Amy L.; Chang, Jean H.; Heegel, Robert A.; Luna, Maria L.; Schepmoes, Athena A.; Shukla, Anil K.; Metz, Thomas O.; Neumann, Gabriele; Benecke, Arndt G.; Smith, Richard D.; Baric, Ralph S.; Kawaoka, Yoshihiro; Katze, Michael G.; Waters, Katrina M.

    2013-01-01

    Respiratory infections stemming from influenza viruses and the Severe Acute Respiratory Syndrome corona virus (SARS-CoV) represent a serious public health threat as emerging pandemics. Despite efforts to identify the critical interactions of these viruses with host machinery, the key regulatory events that lead to disease pathology remain poorly targeted with therapeutics. Here we implement an integrated network interrogation approach, in which proteome and transcriptome datasets from infection of both viruses in human lung epithelial cells are utilized to predict regulatory genes involved in the host response. We take advantage of a novel “crowd-based” approach to identify and combine ranking metrics that isolate genes/proteins likely related to the pathogenicity of SARS-CoV and influenza virus. Subsequently, a multivariate regression model is used to compare predicted lung epithelial regulatory influences with data derived from other respiratory virus infection models. We predicted a small set of regulatory factors with conserved behavior for consideration as important components of viral pathogenesis that might also serve as therapeutic targets for intervention. Our results demonstrate the utility of integrating diverse ‘omic datasets to predict and prioritize regulatory features conserved across multiple pathogen infection models. PMID:23935999

  13. Tracking resistance among bacterial respiratory tract pathogens: summary of findings of the TRUST Surveillance Initiative, 2001-2005.

    PubMed

    Sahm, Daniel F; Brown, Nina P; Draghi, Deborah C; Evangelista, Alan T; Yee, Y Cheung; Thornsberry, Clyde

    2008-09-01

    Antimicrobial resistance observed among common respiratory tract pathogens--Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis--may complicate empiric therapeutic selection to treat community-acquired respiratory tract infections. The Tracking Resistance in the United States Today (TRUST) study determined the in vitro activities of frequently prescribed antimicrobial agents against isolates collected from all 50 states from 2001 to 2005. For S pneumoniae (N = 27,781), susceptibility of selected agents in ascending order were penicillin (oral) (65.4%), trimethoprim-sulfamethoxazole (TMP-SMX) (69.5%), erythromycin (72.0%), cefuroxime (oral) (75.9%), tetracycline (85.3%), amoxicillinclavulanate (92.6%), ceftriaxone (nonmeningitis) (96.6%), and levofloxacin (99.0%). Susceptibility to levofloxacin, which was used as a representative of the respiratory fluoroquinolones, was near 99% from 2001 to 2005, and the minimum inhibitory concentration (90%) (MIC(90)) remained unchanged at 1 microg/mL. Levofloxacin and the other respiratory fluoroquinolones remained highly effective against penicillin-resistant S pneumoniae(PRSP) (98%-99% susceptible). However, susceptibility of PRSP to amoxicillin-clavulanate decreased from 62%S in 2003 to 48%S in 2005. Haemophilus influenzae susceptibility to ampicillin averaged near 70%, and near 75% to TMP-SMX. Susceptibility rates to levofloxacin and the other respiratory fluoroquinolones for H influenzae and M catarrhalis remained at or near 100%. Although resistance rates among S pneumoniae have stabilized for penicillin (oral) at elevated levels and increased for macrolides, susceptibility to the respiratory fluoroquinolones has consistently remained high, as they have for H influenzae and M catarrhalis.

  14. Herpes simplex virus type 1 and respiratory disease in critically-ill patients: Real pathogen or innocent bystander?

    PubMed

    Simoons-Smit, A M; Kraan, E M; Beishuizen, A; Strack van Schijndel, R J; Vandenbroucke-Grauls, C M

    2006-11-01

    Herpes simplex virus type 1 (HSV-1) has been associated with pulmonary disease, mostly in severely immunocompromised patients. After reactivation and shedding in the oropharynx, the virus may reach the lower respiratory tract by aspiration or by contiguous spread. HSV-1 can be detected in clinical specimens by virus culture or quantitatively by nucleic acid amplification techniques. With these techniques, HSV-1 is often detected in the respiratory secretions of critically-ill patients. However, a clear diagnosis of HSV-1 pneumonia is difficult to establish because clinical criteria, radiological features and laboratory findings all lack specificity. Lower respiratory tract HSV-1 infections have not been associated with specific risk-factors. There is also an absence of consistent data concerning the effect of antiviral treatment on the outcome of critically-ill patients. Further studies are needed to better define the pathogenic role of HSV-1 in the lower respiratory tract of these patients, to improve the diagnosis, and, especially, to assess the need for antiviral treatment in the individual patient.

  15. Rapid Identification and Strain-Typing of Respiratory Pathogens for Epidemic Surveillance

    DTIC Science & Technology

    2007-11-02

    understood. Epidemic respiratory infections can be caused by a wide variety of bacteria, including several species of Streptococcus, Haemophilus ... influenzae , Staphylococcus aureus, Neisseria meningitidis, or viruses such as influenza, adeno, rhino, and corona (1, 2). While various culture methods

  16. Lung Biopersistence and in Vitro Dissolution Rate Predict the Pathogenic Potential of Synthetic Vitreous Fibers.

    PubMed

    Hesterberg, T W; Hart, G A

    2000-01-01

    Here we review the past decade of research on inorganic fiber toxicology, which demonstrates that fiber biopersistence and in vitro dissolution rate correlate well with fiber pathogenicity. Test fibers for these studies included eight synthetic vitreous fibers (SVFs)-refractory ceramic fiber (RCF1), four fiber glasses (FCs), rock wool, slag wool, HT stone wool-and two asbestos types (crocidolite and amosite). Fiber toxicology and biopersistence were investigated using rodents exposed by inhalation. To evaluate chronic inhalation toxicity, rodents were exposed nose-only to ∼ 100 fibers >20 µm in length (F > 20 µm)/cm(3), 6 h/day, 5 days/wk, for 2 yr (rats) or 1½ yr (hamsters). To evaluate lung biopersistence, rats were exposed nose-only for 5 days to fiber aerosol; lung burdens were then analyzed during 1 yr postexposure. In vitro dissolution rate was evaluated in a flow-through system using physiological solutions that mimic the inorganic components of extra- and intracellular lung fluids. The 10 test fibers encompassed a range of respiratory toxicities, from transient inflammation only to carcinogenesis. Lung clearance weighted half-times (WT½) for F > 20 µm were 6-15 days for stonewool, building insulation FCs, and slag wool; 50-80 days for rock wool, 2 special-application FCs, and RCFI; and >400 days for asbestos. WT½ correlated with pathogenicity: The rapidly clearing fibers were innocuous (insulation FCs, slag wool, and stonewool), but the more biopersistent fibers were fibrogenic (rock wool) or fibrogenic and carcinogenic (special-application FCs, RCFI, amosite and crocidolite asbestos). In vitro dissolution rates (k dis= ng/cm(2)/h) of the 10 fibers at pH 7.4 or 4.5 ranged from < 1 to >600. Fibers that dissolved rapidly in vitro also cleared quickly from the lung and induced only transient inflammation in the chronic studies. In contrast, fibers that dissolved slowly in vitro were biopersistent in the lung and tended to induce permanent pathogenicity

  17. Effect of High N-Acetylcysteine Concentrations on Antibiotic Activity against a Large Collection of Respiratory Pathogens

    PubMed Central

    Landini, Giulia; Di Maggio, Tiziana; Sergio, Francesco; Docquier, Jean-Denis; Rossolini, Gian Maria

    2016-01-01

    The effect of high N-acetylcysteine (NAC) concentrations (10 and 50 mM) on antibiotic activity against 40 strains of respiratory pathogens was investigated. NAC compromised the activity of carbapenems (of mostly imipenem and, to lesser extents, meropenem and ertapenem) in a dose-dependent fashion. We demonstrated chemical instability of carbapenems in the presence of NAC. With other antibiotics, 10 mM NAC had no major effects, while 50 mM NAC sporadically decreased (ceftriaxone and aminoglycosides) or increased (penicillins) antibiotic activity. PMID:27736757

  18. Mortality and Morbidity Avoidance/Reduction of Respiratory Sickness Immediately Following Exposure to Bioweaponized Microbial Pathogens

    DTIC Science & Technology

    2007-11-02

    vegetative cells of Bacillus anthracis, Clostridium spp., fungal lung pathogens in general and cells of Yersinia pestis, Francisella tularensis, Brucella suis, Salmonella typhi and related bacterial species.

  19. Personal clothing as a potential vector of respiratory virus transmission in childcare settings.

    PubMed

    Gralton, Jan; McLaws, Mary-Louise; Rawlinson, William D

    2015-06-01

    Previous investigations of fomite transmission have focused on the presence of pathogens on inanimate objects in clinical settings. There has been limited investigation of fomite transmission in non-clinical pediatric settings where there is a high prevalence of respiratory virus infections. Over a 5 week period, this study investigated whether the personal clothing of teachers working in childcare centers was contaminated with viral RNA, and potentially could mediate virus transmission. Matched morning and evening clothing and nasal samples were collected for 313 teacher work days (TWDs). Human rhinoviruses (hRV) RNA were detected from samples using real-time PCR. Human rhinovirus RNA was detected in clothing samples on 16 TWDs and in nasal samples on 32 TWDs. There were no TWDs when teachers provided both positive nasal and clothing samples and only three TWDs when hRV persisted on clothing for the entire day. The detection of hRV RNA was significantly predicted by self-recognition of symptomatic illness by the teacher 2 days prior to detection. These findings suggest that teachers' personal clothing in childcare settings is unlikely to facilitate the transmission of hRV.

  20. Aspirin as a potential treatment in sepsis or acute respiratory distress syndrome.

    PubMed

    Toner, Philip; McAuley, Danny Francis; Shyamsundar, Murali

    2015-10-23

    Sepsis is a common condition that is associated with significant morbidity, mortality and health-care cost. Pulmonary and non-pulmonary sepsis are common causes of the acute respiratory distress syndrome (ARDS). The mortality from ARDS remains high despite protective lung ventilation, and currently there are no specific pharmacotherapies to treat sepsis or ARDS. Sepsis and ARDS are characterised by activation of the inflammatory cascade. Although there is much focus on the study of the dysregulated inflammation and its suppression, the associated activation of the haemostatic system has been largely ignored until recently. There has been extensive interest in the role that platelet activation can have in the inflammatory response through induction, aggregation and activation of leucocytes and other platelets. Aspirin can modulate multiple pathogenic mechanisms implicated in the development of multiple organ dysfunction in sepsis and ARDS. This review will discuss the role of the platelet, the mechanisms of action of aspirin in sepsis and ARDS, and aspirin as a potential therapy in treating sepsis and ARDS.

  1. Exploring the potential of next-generation sequencing in detection of respiratory viruses.

    PubMed

    Prachayangprecha, Slinporn; Schapendonk, Claudia M E; Koopmans, Marion P; Osterhaus, Albert D M E; Schürch, Anita C; Pas, Suzan D; van der Eijk, Annemiek A; Poovorawan, Yong; Haagmans, Bart L; Smits, Saskia L

    2014-10-01

    Efficient detection of human respiratory viral pathogens is crucial in the management of patients with acute respiratory tract infection. Sequence-independent amplification of nucleic acids combined with next-generation sequencing technology and bioinformatics analyses is a promising strategy for identifying pathogens in clinical and public health settings. It allows the characterization of hundreds of different known pathogens simultaneously and of novel pathogens that elude conventional testing. However, major hurdles for its routine use exist, including cost, turnaround time, and especially sensitivity of the assay, as the detection limit is dependent on viral load, host genetic material, and sequencing depth. To obtain insights into these aspects, we analyzed nasopharyngeal aspirates from a cohort of 81 Thai children with respiratory disease for the presence of respiratory viruses using a sequence-independent next-generation sequencing approach and routinely used diagnostic real-time reverse transcriptase PCR (real-time RT-PCR) assays. With respect to the detection of rhinovirus and human metapneumovirus, the next-generation sequencing approach was at least as sensitive as diagnostic real-time RT-PCR in this small cohort, whereas for bocavirus and enterovirus, next-generation sequencing was less sensitive than real-time RT-PCR. The advantage of the sequencing approach over real-time RT-PCR was the immediate availability of virus-typing information. Considering the development of platforms capable of generating more output data at declining costs, next-generation sequencing remains of interest for future virus diagnosis in clinical and public health settings and certainly as an additional tool when screening results from real-time RT-PCR are negative.

  2. Transcriptomic analysis reveals the potential of highly pathogenic PRRS virus to modulate immune system activation related to host-pathogen and damage associated signaling in infected porcine monocytes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One of the largest risks to the continued stability of the swine industry is by pathogens like porcine reproductive and respiratory syndrome virus (PRRSV) that can decimate production as it spreads among individuals. These infections can be low or highly pathogenic, and because it infects monocytic ...

  3. Endobiotic bacteria and their pathogenic potential in cnidarian tentacles

    NASA Astrophysics Data System (ADS)

    Schuett, Christian; Doepke, Hilke

    2010-09-01

    Endobiotic bacteria colonize the tentacles of cnidaria. This paper provides first insight into the bacterial spectrum and its potential of pathogenic activities inside four cnidarian species. Sample material originating from Scottish waters comprises the jellyfish species Cyanea capillata and C. lamarckii, hydrozoa Tubularia indivisa and sea anemone Sagartia elegans. Mixed cultures of endobiotic bacteria, pure cultures selected on basis of haemolysis, but also lyophilized samples were prepared from tentacles and used for DGGE-profiling with subsequent phylogenetic analysis of 16S rDNA fragments. Bacteria were detected in each of the cnidarian species tested. Twenty-one bacterial species including four groups of closely related organisms were found in culture material. The species within these groups could not be differentiated from each other (one group of Pseudoalteromonas spp., two groups of Shewanella spp., one group of Vibrio spp.). Each of the hosts exhibits a specific endobacterial spectrum. Solely Cyanea lamarckii harboured Moritella viscosa. Only in Cyanea capillata, members of the Shewanella group #2 and the species Pseudoalteromonas arctica, Shewanella violacea, Sulfitobacter pontiacus and Arcobacter butzleri were detected. Hydrozoa Tubularia indivisa provided an amazingly wide spectrum of nine bacterial species. Exclusively, in the sea anemone Sagartia elegans, the bacterial species P. aliena was found. Overall eleven bacterial species detected were described recently as novel species. Four 16S rDNA fragments generated from lyophilized material displayed extremely low relationship to their next neighbours. These organisms are regarded as members of the endobiotic “terra incognita”. Since the origin of cnidarian toxins is unclear, the possible pathogenic activity of endobiotic bacteria has to be taken into account. Literature data show that their next neighbours display an interesting diversity of haemolytic, septicaemic and necrotic actions including

  4. Macrolones Are a Novel Class of Macrolide Antibiotics Active against Key Resistant Respiratory Pathogens In Vitro and In Vivo

    PubMed Central

    Verbanac, Donatella; Padovan, Jasna; Dominis-Kramarić, Miroslava; Kelnerić, Željko; Perić, Mihaela; Banjanac, Mihailo; Ergović, Gabrijela; Simon, Nerrisa; Broskey, John; Holmes, David J.; Eraković Haber, Vesna

    2016-01-01

    As we face an alarming increase in bacterial resistance to current antibacterial chemotherapeutics, expanding the available therapeutic arsenal in the fight against resistant bacterial pathogens causing respiratory tract infections is of high importance. The antibacterial potency of macrolones, a novel class of macrolide antibiotics, against key respiratory pathogens was evaluated in vitro and in vivo. MIC values against Streptococcus pneumoniae, Streptococcus pyogenes, Staphylococcus aureus, and Haemophilus influenzae strains sensitive to macrolide antibiotics and with defined macrolide resistance mechanisms were determined. The propensity of macrolones to induce the expression of inducible erm genes was tested by the triple-disk method and incubation in the presence of subinhibitory concentrations of compounds. In vivo efficacy was assessed in a murine model of S. pneumoniae-induced pneumonia, and pharmacokinetic (PK) profiles in mice were determined. The in vitro antibacterial profiles of macrolones were superior to those of marketed macrolide antibiotics, including the ketolide telithromycin, and the compounds did not induce the expression of inducible erm genes. They acted as typical protein synthesis inhibitors in an Escherichia coli transcription/translation assay. Macrolones were characterized by low to moderate systemic clearance, a large volume of distribution, a long half-life, and low oral bioavailability. They were highly efficacious in a murine model of pneumonia after intraperitoneal application even against an S. pneumoniae strain with constitutive resistance to macrolide-lincosamide-streptogramin B antibiotics. Macrolones are the class of macrolide antibiotics with an outstanding antibacterial profile and reasonable PK parameters resulting in good in vivo efficacy. PMID:27353268

  5. Pathogenicity and Molecular Characterization of Emerging Porcine Reproductive and Respiratory Syndrome Virus in Vietnam in 2007

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In 2007, Vietnam experienced swine disease outbreaks causing clinical signs similar to the "porcine high fever disease" that occurred in China during 2006. Analysis of diagnostic samples from the disease outbreaks in Vietnam identified porcine reproductive and respiratory syndrome virus (PRRSV) and ...

  6. Partial denture metal framework may harbor potentially pathogenic bacteria

    PubMed Central

    Bernardes, Luciano Angelo de Souza; Gomes, Sabrina Carvalho; Silva, Alecsandro Moura

    2015-01-01

    PURPOSE The aim of this study was to characterize and compare bacterial diversity on the removable partial denture (RPD) framework over time. MATERIALS AND METHODS This descriptive pilot study included five women who were rehabilitated with free-end mandibular RPD. The biofilm on T-bar clasps were collected 1 week (t1) and 4 months (t2) after the RPD was inserted (t0). Bacterial 16S rDNA was extracted and PCR amplified. Amplicons were cloned; clones were submitted to cycle sequencing, and sequences were compared with GenBank (98% similarity). RESULTS A total of 180 sequences with more than 499 bp were obtained. Two phylogenetic trees with 84 (t1) and 96 (t2) clones represented the bacteria biofilm at the RPD. About 93% of the obtained phylotypes fell into 25 known species for t1 and 17 for t2, which were grouped in 5 phyla: Firmicutes (t1=82%; t2=60%), Actinobacteria (t1=5%; t2=10%), Bacteroidetes (t1=2%; t2=6%), Proteobacteria (t1=10%; t2=15%) and Fusobacteria (t1=1%; t2=8%). The libraries also include 3 novel phylotypes for t1 and 11 for t2. Library t2 differs from t1 (P=.004); t1 is a subset of the t2 (P=.052). Periodontal pathogens, such as F. nucleatum, were more prevalent in t2. CONCLUSION The biofilm composition of the RPD metal clasps changed along time after RPD wearing. The RPD framework may act as a reservoir for potentially pathogenic bacteria and the RPD wearers may benefit from regular follow-up visits and strategies on prosthesis-related oral health instructions. PMID:26816577

  7. Potential versus actual contribution of vertical transmission to pathogen fitness

    PubMed Central

    Kover, P. X.; Dolan, T. E.; Clay, K.

    1997-01-01

    Theory predicts that virulent parasites cannot be maintained at high prevalence if they are only vertically transmitted. However, parasites with high rates of vertical transmission that cause severe reduction in host fitness have been reported. Atkinsonella hypoxylon is a fungal pathogen capable of both vertical and horizontal transmission that drastically reduces its host's fitness. In contrast with theoretical predictions, field and laboratory observations suggested that the primary mechanism of transmission was vertical. Using randomly amplified polymorphic DNA markers, we investigated the effective contribution of vertical and horizontal transmission to the genetic structure of three natural populations of A. hypoxylon. We found high genotypic diversity and low linkage disequilibrium, indicating that most established genotypes are derived from horizontally transmitted, sexual spores. The low contribution of vertical transmission to the parasite's fitness despite its high potential might be due to lower establishment of cleistogamous seeds (through which vertical transmission occurs) or lower vigour of vertically transmitted fungal genotypes. Low establishment of vertically infected hosts might explain the persistence of virulent parasites with high apparent vertical transmission. Our results suggest that caution must be taken when using the potential for vertical transmission to make predictions about the evolution of parasite virulence.

  8. [Potential neurocognitive consequences of infection by human respiratory syncytial virus].

    PubMed

    Flores, Juan Carlos; Bohmwald, Karen; Espinoza, Janyra; Jara, Crlstlna; Peña, Marcela; Hoyos-Bachiloglu, Rodrigo; Iturriaga, Carolina; Kalergis, Alexis M; Borzutzky, Arturo

    2016-10-01

    Human respiratory syncytial virus (RSV) infection remains as a major cause of morbidity and mortality among pediatric population. Immune response is poor and unable to establish a long term effective protection against this virus. Of particular interest has been the description of extrapulmonary manifestations of RSV infection in liver, kidney, endocrine system, heart and brain, associated to infection of peripheral blood. In the central nervous system (CNS), recent studies in animals have suggested long term neurocognitive impairment due to a direct damage from the virus. This was prevented in rats by a recombinant BCG vaccine expressing a nucleoprotein N of RSV that produces an effective immune response against the virus, not allowing its dissemination to the CNS. These findings in animal models highlight the importance of conducting more specific studies in children affected with severe infection by RSV. Therefore, our group is currently conducting an assessment of the possible long-term cognitive impairment in children under 2 years. The results of this study could be a strong argument to continue looking for an effective method for protecting against RSV infection.

  9. *Biomarkers of acute respiratory allergen exposure: Screening for sensitization potential

    EPA Science Inventory

    Effective hazard screening will require the development of high-throughput or in vitro assays for the identification of potential sensitizers. The goal of this preliminary study was to identify potential biomarkers that differentiate the response to allergens vs non-allergens fol...

  10. Molecular characterization of transcriptome-wide interactions between highly pathogenic porcine reproductive and respiratory syndrome virus and porcine alveolar macrophages in vivo.

    PubMed

    Zhou, Ping; Zhai, Shanli; Zhou, Xiang; Lin, Ping; Jiang, Tengfei; Hu, Xueying; Jiang, Yunbo; Wu, Bin; Zhang, Qingde; Xu, Xuewen; Li, Jin-Ping; Liu, Bang

    2011-01-01

    Porcine reproductive and respiratory syndrome virus (PRRSV) infects mainly the porcine alveolar macrophages (PAMs) and causes porcine reproductive and respiratory syndrome (PRRS). Previous studies have analyzed the global gene expression profiles of lung tissue in vivo and PAMs in vitro following infection with PRRSV, however, transcriptome-wide understanding of the interaction between highly pathogenic PRRSV (HP-PRRSV) and PAMs in vivo has not yet been established. In this study, we employed Affymetrix microarrays to investigate the gene expression patterns of PAMs isolated from Tongcheng piglets (a Chinese indigenous breed) after infection with HP-PRRSV. During the infection, Tongcheng piglets exhibited typical clinical signs, e.g. fever, asthma, coughing, anorexia, lethargy and convulsion, but displayed mild regional lung damage at 5 and 7 dpi. Microarray analysis revealed that HP-PRRSV infection has affected PAMs in expression of the important genes involved in cytoskeleton and exocytosis organization, protein degradation and folding, intracellular calcium and zinc homeostasis. Several potential antiviral strategies might be employed in PAMs, including upregulating IFN-induced genes and increasing intracellular zinc ion concentration. And inhibition of the complement system likely attenuated the lung damage during HP-PRRSV infection. Transcriptomic analysis of PAMs in vivo could lead to a better understanding of the HP-PRRSV-host interaction, and to the identification of novel antiviral therapies and genetic components of swine tolerance/susceptibility to HP-PRRS.

  11. Draft genome sequences for ten isolates of the swine respiratory pathogen Haemophilus Parasuis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Haemophilus parasuis is a swine pathogen that causes pneumonia and Glässer’s disease, a systemic syndrome of polyserositis, arthritis, and meningitis. We report here the draft genomes of ten geographically diverse isolates collectively representing the full virulence spectrum of H. parasuis. These...

  12. Location and pathogenic potential of Blastocystis in the porcine intestine.

    PubMed

    Wang, Wenqi; Bielefeldt-Ohmann, Helle; Traub, Rebecca J; Cuttell, Leigh; Owen, Helen

    2014-01-01

    Blastocystis is an ubiquitous, enteric protozoan of humans and many other species. Human infection has been associated with gastrointestinal disease such as irritable bowel syndrome, however, this remains unproven. A relevant animal model is needed to investigate the pathogenesis/pathogenicity of Blastocystis. We concluded previously that pigs are likely natural hosts of Blastocystis with a potentially zoonotic, host-adapted subtype (ST), ST5, and may make suitable animal models. In this study, we aimed to characterise the host-agent interaction of Blastocystis and the pig, including localising Blastocystis in porcine intestine using microscopy, PCR and histopathological examination of tissues. Intestines from pigs in three different management systems, i.e., a commercial piggery, a small family farm and a research herd (where the animals were immunosuppressed) were examined. This design was used to determine if environment or immune status influences intestinal colonisation of Blastocystis as immunocompromised individuals may potentially be more susceptible to blastocystosis and development of associated clinical signs. Intestines from all 28 pigs were positive for Blastocystis with all pigs harbouring ST5. In addition, the farm pigs had mixed infections with STs 1 and/or 3. Blastocystis organisms/DNA were predominantly found in the large intestine but were also detected in the small intestine of the immunosuppressed and some of the farm pigs, suggesting that immunosuppression and/or husbandry factors may influence Blastocystis colonisation of the small intestine. No obvious pathology was observed in the histological sections. Blastocystis was present as vacuolar/granular forms and these were found within luminal material or in close proximity to epithelial cells, with no evidence of attachment or invasion. These results concur with most human studies, in which Blastocystis is predominantly found in the large intestine in the absence of significant organic

  13. Insights into host-pathogen interactions from state-of-the-art animal models of respiratory Pseudomonas aeruginosa infections.

    PubMed

    Lorenz, Anne; Pawar, Vinay; Häussler, Susanne; Weiss, Siegfried

    2016-11-01

    Pseudomonas aeruginosa is an important opportunistic pathogen that can cause acute respiratory infections in immunocompetent patients or chronic infections in immunocompromised individuals and in patients with cystic fibrosis. When acquiring the chronic infection state, bacteria are encapsulated within biofilm structures enabling them to withstand diverse environmental assaults, including immune reactions and antimicrobial therapy. Understanding the molecular interactions within the bacteria, as well as with the host or other bacteria, is essential for developing innovative treatment strategies. Such knowledge might be accumulated in vitro. However, it is ultimately necessary to confirm these findings in vivo. In the present Review, we describe state-of-the-art in vivo models that allow studying P. aeruginosa infections in molecular detail. The portrayed mammalian models exclusively focus on respiratory infections. The data obtained by alternative animal models which lack lung tissue, often provide molecular insights that are easily transferable to mammals. Importantly, these surrogate in vivo systems reveal complex molecular interactions of P. aeruginosa with the host. Herein, we also provide a critical assessment of the advantages and disadvantages of such models.

  14. Seroprevalence of respiratory viral pathogens of indigenous calves in Western Kenya.

    PubMed

    Callaby, R; Toye, P; Jennings, A; Thumbi, S M; Coetzer, J A W; Conradie Van Wyk, I C; Hanotte, O; Mbole-Kariuki, M N; Bronsvoort, B M de C; Kruuk, L E B; Woolhouse, M E J; Kiara, H

    2016-10-01

    Most studies of infectious diseases in East African cattle have concentrated on gastro-intestinal parasites and vector-borne diseases. As a result, relatively little is known about viral diseases, except for those that are clinically symptomatic or which affect international trade such as foot and mouth disease, bluetongue and epizootic haemorrhagic disease. Here, we investigate the seroprevalence, distribution and relationship between the viruses involved in respiratory disease, infectious bovine rhinotracheitis virus (IBR), bovine parainfluenza virus Type 3 (PIV3) and bovine viral diarrhoea virus (BVDV) in East African Shorthorn Zebu calves. These viruses contribute to the bovine respiratory disease complex (BRD) which is responsible for major economic losses in cattle from intensive farming systems as a result of pneumonia. We found that calves experience similar risks of infection for IBR, PIV3, and BVDV with a seroprevalence of 20.9%, 20.1% and 19.8% respectively. We confirm that positive associations exist between IBR, PIV3 and BVDV; being seropositive for any one of these three viruses means that an individual is more likely to be seropositive for the other two viruses than expected by chance.

  15. In vitro activity of ABT-773 versus macrolides and quinolones against resistant respiratory tract pathogens.

    PubMed

    Dubois, J; St -Pierre, C

    2001-01-01

    ABT-773, a novel ketolide, was compared to erythromycin, azithromycin, clarithromycin, ciprofloxacin, ofloxacin, levofloxacin, moxifloxacin, gatifloxacin, and gemifloxacin against antibiotic-resistant strains recently isolated from patients with respiratory tract infections. MICs were determined by agar dilution using standard NCCLS methodology. ABT-773 (MIC(90) 0.06 mg/L) was more active than the macrolides (MIC(90) > or = 2 mg/L) and fluoroquinolones (MIC(90) > or = 0.5 mg/L) against penicillin-resistant Streptococcus pneumoniae. The fluoroquinolones were the most active agents tested against beta-lactamase-positive Haemophilus influenzae (MIC(90) < or = 0.01-0.06 mg/L), against which ABT-773 (MIC(90) 4 mg/L) was comparable to azithromycin and two- and four-fold more active than erythromycin and clarithromycin, respectively. Against beta-lactamase positive Moraxella catarrhalis, the activity of ABT-773 (MIC(90) 0.06 mg/L) was comparable to gemifloxacin, trovafloxacin, levofloxacin, and ciprofloxacin (MIC(90) 0.03-0.06 mg/L) and 4- to eightfold greater than that of clarithromycin, gatifloxacin, and erythromycin. These data suggest ABT-773 could be a valuable compound for the treatment of respiratory tract infections, including those resistant to usual oral therapy.

  16. Prevalence of Pasteurella multocida and other respiratory pathogens in the nasal tract of Scottish calves.

    PubMed

    Hotchkiss, E J; Dagleish, M P; Willoughby, K; McKendrick, I J; Finlayson, J; Zadoks, R N; Newsome, E; Brulisauer, F; Gunn, G J; Hodgson, J C

    2010-10-09

    The prevalence of Pasteurella multocida, a cause of bovine respiratory disease, was studied in a random sample of beef suckler and dairy farms throughout Scotland, by means of a cross-sectional survey. A total of 637 calves from 68 farms from six geographical regions of Scotland were sampled between February and June 2008. Deep nasal swabs were taken, and samples that were culture-positive for P multocida were confirmed by PCR. Prevalence of P multocida was 17 per cent (105 of 616 calves); 47 per cent of farms had at least one positive animal. A higher prevalence was detected in dairy calves than beef calves (P=0.04). It was found that P multocida was associated with Mycoplasma-like organisms (P=0.06) and bovine parainfluenza type 3 virus (BPI-3) (P=0.04), detected by culture and quantitative PCR of nasal swabs, respectively. Detection of P multocida was not associated with bovine respiratory syncytial virus (BRSV), bovine herpesvirus type 1 (BoHV-1) or bovine viral diarrhoea virus (BVDV). Mycoplasma-like organisms, BPI-3, BRSV, BoHV-1 and BVDV were detected in 58, 17, four, 0 and eight calves, on 25, five, two, 0 and five of the 68 farms, respectively.

  17. Host-pathogen interplay in the respiratory environment of Cystic Fibrosis

    PubMed Central

    Hurley, Bryan P.; Bragonzi, Alessandra

    2015-01-01

    Significant advances have been made in the understanding of disease progression in cystic fibrosis (CF), revealing a complex interplay between host and pathogenic organisms. The diverse CF microbiota within the airway activates an aberrant immune response that is ineffective in clearing infection. An appreciation of how the CF host immune system interacts with these organisms is crucial to understanding the pathogenesis of CF pulmonary disease. Here we discuss the microbial complexity present in the lungs of individuals with CF, review emerging concepts of innate and adaptive immune responses to pathogens that chronically inhabit the CF lung, and discuss therapies that target the aberrant inflammatory response that characterizes CF. A greater understanding of the underlying mechanisms will shed light on pathogenesis and guide more targeted therapies in the future that serve to reduce infection, minimize lung pathology, and improve the quality of life for patients with CF. PMID:25800687

  18. Lytic bacteriophages: Potential interventions against enteric bacterial pathogens on produce.

    PubMed

    Sharma, Manan

    2013-04-01

    Foodborne illnesses resulting from the consumption of produce commodities contaminated with enteric pathogens continue to be a significant public health issue. Lytic bacteriophages may provide an effective and natural intervention to reduce bacterial pathogens on fresh and fresh-cut produce commodities. The use of multi-phage cocktails specific for a single pathogen has been most frequently assessed on produce commodities to minimize the development of bacteriophage insensitive mutants (BIM) in target pathogen populations. Regulatory approval for the use of several lytic phage products specific for bacterial pathogens such as Escherichia coli O157:H7, Salmonella spp. and Listeria monocytogenes in foods and on food processing surfaces has been granted by various agencies in the US and other countries, possibly allowing for the more widespread use of bacteriophages in the decontamination of fresh and minimally processed produce. Research studies have shown lytic bacteriophages specific for E. coli O157:H7, Salmonella spp. and Listeria monocytogenes have been effective in reducing pathogen populations on leafy greens, sprouts and tomatoes.

  19. Identification and Pathogenic Potential of Clinical Bacillus and Paenibacillus Isolates.

    PubMed

    Celandroni, Francesco; Salvetti, Sara; Gueye, Sokhna Aissatou; Mazzantini, Diletta; Lupetti, Antonella; Senesi, Sonia; Ghelardi, Emilia

    2016-01-01

    The soil-related Bacillus and Paenibacillus species have increasingly been implicated in various human diseases. Nevertheless, their identification still poses problems in the clinical microbiology laboratory and, with the exception of Bacillus anthracis and Bacillus cereus, little is known on their pathogenicity for humans. In this study, we evaluated the use of matrix-assisted laser desorption-ionization time of flight mass spectrometry (MALDI-TOF MS) in the identification of clinical isolates of these genera and conducted genotypic and phenotypic analyses to highlight specific virulence properties. Seventy-five clinical isolates were subjected to biochemical and MALDI-TOF MS identification. 16S rDNA sequencing and supplemental tests were used to solve any discrepancies or failures in the identification results. MALDI-TOF MS significantly outperformed classical biochemical testing for correct species identification and no misidentification was obtained. One third of the collected strains belonged to the B. cereus species, but also Bacillus pumilus and Bacillus subtilis were isolated at high rate. Antimicrobial susceptibility testing showed that all the B. cereus, B. licheniformis, B. simplex, B. mycoides, Paenibacillus glucanolyticus and Paenibacillus lautus isolates are resistant to penicillin. The evaluation of toxin/enzyme secretion, toxin-encoding genes, motility, and biofilm formation revealed that B. cereus displays the highest virulence potential. However, although generally considered nonpathogenic, most of the other species were shown to swim, swarm, produce biofilms, and secrete proteases that can have a role in bacterial virulence. In conclusion, MALDI-TOF MS appears useful for fast and accurate identification of Bacillus and Paenibacillus strains whose virulence properties make them of increasing clinical relevance.

  20. Identification and Pathogenic Potential of Clinical Bacillus and Paenibacillus Isolates

    PubMed Central

    Celandroni, Francesco; Salvetti, Sara; Gueye, Sokhna Aissatou; Mazzantini, Diletta; Lupetti, Antonella; Senesi, Sonia; Ghelardi, Emilia

    2016-01-01

    The soil-related Bacillus and Paenibacillus species have increasingly been implicated in various human diseases. Nevertheless, their identification still poses problems in the clinical microbiology laboratory and, with the exception of Bacillus anthracis and Bacillus cereus, little is known on their pathogenicity for humans. In this study, we evaluated the use of matrix-assisted laser desorption—ionization time of flight mass spectrometry (MALDI-TOF MS) in the identification of clinical isolates of these genera and conducted genotypic and phenotypic analyses to highlight specific virulence properties. Seventy-five clinical isolates were subjected to biochemical and MALDI-TOF MS identification. 16S rDNA sequencing and supplemental tests were used to solve any discrepancies or failures in the identification results. MALDI-TOF MS significantly outperformed classical biochemical testing for correct species identification and no misidentification was obtained. One third of the collected strains belonged to the B. cereus species, but also Bacillus pumilus and Bacillus subtilis were isolated at high rate. Antimicrobial susceptibility testing showed that all the B. cereus, B. licheniformis, B. simplex, B. mycoides, Paenibacillus glucanolyticus and Paenibacillus lautus isolates are resistant to penicillin. The evaluation of toxin/enzyme secretion, toxin-encoding genes, motility, and biofilm formation revealed that B. cereus displays the highest virulence potential. However, although generally considered nonpathogenic, most of the other species were shown to swim, swarm, produce biofilms, and secrete proteases that can have a role in bacterial virulence. In conclusion, MALDI-TOF MS appears useful for fast and accurate identification of Bacillus and Paenibacillus strains whose virulence properties make them of increasing clinical relevance. PMID:27031639

  1. Pathogenic Potential of Saccharomyces Strains Isolated from Dietary Supplements

    PubMed Central

    Monteoliva, Lucía; Querol, Amparo; Molina, María; Fernández-Espinar, María T.

    2014-01-01

    Saccharomyces cerevisiae plays a beneficial role in health because of its intrinsic nutritional value and bio-functional properties, which is why it is also used as a dietary supplement. However, the perception that S. cerevisiae is harmless has changed due to an increasing number of infections caused by this yeast. Given this scenario, we have tested whether viable strains contained in dietary supplements displayed virulence-associated phenotypic traits that could contribute to virulence in humans. We have also performed an in vivo study of the pathogenic potential of these strains using a murine model of systemic infection by intravenous inoculation. A total of 5 strains were isolated from 22 commercial products and tested. Results highlight one strain (D14) in terms of burden levels in brains and kidneys and ability to cause death, whereas the other two strains (D2 and D4) were considered of low virulence. Our results suggest a strong relationship between some of the virulence-associated phenotypic traits (ability to grow at 39°C and pseudohyphal growth) and the in vivo virulence in a mouse model of intravenous inoculation for isolates under study. The isolate displaying greatest virulence (D14) was evaluated in an experimental murine model of gastrointestinal infection with immunosuppression and disruption of mucosal integrity, which are common risk factors for developing infection in humans, and results were compared with an avirulent strain (D23). We showed that D14 was able to spread to mesenteric nodes and distant organs under these conditions. Given the widespread consumption of dietary supplements, we recommend only safe strains be used. PMID:24879417

  2. The Chinese highly pathogenic porcine reproductive and respiratory syndrome virus infection suppresses Th17 cells response in vivo.

    PubMed

    Zhang, Long; Zhou, Lei; Ge, Xinna; Guo, Xin; Han, Jun; Yang, Hanchun

    2016-06-30

    Porcine reproductive and respiratory syndrome virus (PRRSV) has been shown to immunomodulate innate and adaptive immunity of pigs. The Chinese highly pathogenic PRRSV (HP-PRRSV) infection causes severe bacterial secondary infection in pigs. However, the mechanism in relation to the bacterial secondary infection induced by HP-PRRSV remains unknown. In the present study, Th17 cells response in peripheral blood, lungs, spleens and lymph nodes of piglets were analyzed, and bacterial loads in lungs of piglets were examined upon HP-PRRSV infection. Meanwhile the changes of CD4(+) and CD8(+) T cells in peripheral blood of the inoculated piglets were analyzed. The results showed that HP-PRRSV-inoculated piglets exhibited a suppressed Th17 cells response in peripheral blood and a reduced number of Th17 cells in lungs, and higher bacterial loads in lungs, compared with low pathogenic PRRSV. Moreover, HP-PRRSV obviously resulted in severe depletion of porcine T cells in peripheral blood at the early stage of infection. These findings indicate that HP-PRRSV infection suppresses the response of Th17 cells that play an important role in combating bacterial infections, suggesting a possible correlation between the suppression of Th17 cells response in vivo and bacterial secondary infection induced by HP-PRRSV. Our present study adds a novel insight into better understanding of the pathogenesis of the Chinese HP-PRRSV.

  3. CYTOKINE MRNA PROFILES FOR ISOCYANATES WITH KNOWN AND UNKNOWN POTENTIAL TO INDUCE RESPIRATORY SENSITIZATION

    EPA Science Inventory

    Cytokine mRNA Profiles for Isocyanates with Known and Unknown Potential to Induce Respiratory Sensitization. Plitnick, L.M., Loveless, S.E., Ladics, G.S., Holsapple, M.P., Smialowicz, R.J., Woolhiser, M.R., Anderson, P.K., Smith, C., Sailstad, D.M. and Selgrade, M.J.K (2002) Tox...

  4. CURRENT STATE OF PREDICTING THE RESPIRATORY ALLERGY POTENTIAL OF CHEMICALS: WHAT ARE THE ISSUES?

    EPA Science Inventory

    Current State of Predicting the Respiratory Allergy Potential of Chemicals: What Are the Issues? M I. Gilmour1 and S. E. Loveless2, 1USEPA, Research Triangle Park, NC and 2DuPont Haskell Laboratory, Newark, DE.

    Many chemicals are clearly capable of eliciting immune respon...

  5. Potential risk of pathogen transmission by acaricide-poisoned ticks.

    PubMed

    Uspensky, Igor; Ioffe-Uspensky, Inna

    2006-05-01

    stage for DDT or 1st to 2nd for fenthion), they can attach to hosts and imbibe blood. The average body weight of such ticks after repletion corresponded to that of control ticks. Engorged nymphal ticks normally molted to adults, engorged females normally oviposited, and their progeny did not differ from the progeny of control females. This second important phenomenon, called 'overcoming the poisoning', was observed in all studied species of ticks from several genera. Thus, the slow development of tick poisoning creates a potential for ticks to attach to hosts and to gorge blood, and for infected ticks to transmit pathogens to those hosts, while the ability to overcome the poisoning allows the ticks to survive and makes possible the subsequent trans-stadial and transovarial passage of pathogens. These data can be considered as strong circumstantial evidence of the risk that ticks can present to humans and animals at the initial stages of poisoning after acaricide treatment.

  6. In Vitro Activity of Solithromycin against Bordetella pertussis, an Emerging Respiratory Pathogen

    PubMed Central

    Vicino, David; Fernandes, Prabhavathi

    2016-01-01

    There has been an increase in the number of pertussis cases reported since the introduction of the acellular pertussis vaccine. While children that present with pertussis have a characteristic whooping cough, adults can simply have a persistent, nonspecific cough and remain undiagnosed. Macrolide antibiotics, such as azithromycin, are the currently recommended treatment for pertussis. Solithromycin is a new macrolide and the first fluoroketolide with broad activity against a wide spectrum of bacterial pathogens and has completed clinical development for community-acquired bacterial pneumonia. This study reports the potent in vitro activity of solithromycin against a collection of recent isolates of Bordetella pertussis. PMID:27620481

  7. Inhibitory activity of a standardized elderberry liquid extract against clinically-relevant human respiratory bacterial pathogens and influenza A and B viruses

    PubMed Central

    2011-01-01

    Background Black elderberries (Sambucus nigra L.) are well known as supportive agents against common cold and influenza. It is further known that bacterial super-infection during an influenza virus (IV) infection can lead to severe pneumonia. We have analyzed a standardized elderberry extract (Rubini, BerryPharma AG) for its antimicrobial and antiviral activity using the microtitre broth micro-dilution assay against three Gram-positive bacteria and one Gram-negative bacteria responsible for infections of the upper respiratory tract, as well as cell culture experiments for two different strains of influenza virus. Methods The antimicrobial activity of the elderberry extract was determined by bacterial growth experiments in liquid cultures using the extract at concentrations of 5%, 10%, 15% and 20%. The inhibitory effects were determined by plating the bacteria on agar plates. In addition, the inhibitory potential of the extract on the propagation of human pathogenic H5N1-type influenza A virus isolated from a patient and an influenza B virus strain was investigated using MTT and focus assays. Results For the first time, it was shown that a standardized elderberry liquid extract possesses antimicrobial activity against both Gram-positive bacteria of Streptococcus pyogenes and group C and G Streptococci, and the Gram-negative bacterium Branhamella catarrhalis in liquid cultures. The liquid extract also displays an inhibitory effect on the propagation of human pathogenic influenza viruses. Conclusion Rubini elderberry liquid extract is active against human pathogenic bacteria as well as influenza viruses. The activities shown suggest that additional and alternative approaches to combat infections might be provided by this natural product. PMID:21352539

  8. The role of atypical respiratory pathogens in exacerbations of chronic obstructive pulmonary disease.

    PubMed

    Diederen, B M W; van der Valk, P D L P M; Kluytmans, J A W J; Peeters, M F; Hendrix, R

    2007-08-01

    The aetiology of acute exacerbations of chronic obstructive pulmonary disease (COPD) is heterogeneous and still under discussion. Serological studies have suggested that Mycoplasma pneumoniae, Chlamydia pneumoniae and Legionella pneumophila may play a role in acute exacerbations of COPD. The presence of these atypical pathogens in sputum samples was investigated in patients with stable COPD and with acute exacerbations of COPD using real-time PCR. The present study was part of a randomised, double-blind, single-centre study and a total of 248 sputum samples from 104 COPD patients were included. In total, 122 samples obtained during stable disease (stable-state sputa) and 126 samples obtained during acute exacerbations of COPD (exacerbation sputa) were tested. Of the 122 stable-state sputa, all samples were negative for M. pneumoniae and C. pneumoniae DNA, whereas one sample was positive for Legionella non-pneumophila DNA. Of the 126 exacerbation sputa, all samples were negative for M. pneumoniae and C. pneumoniae DNA, whereas one sample was positive for Legionella non-pneumophila DNA. The possible relationship between the presence of atypical pathogens and the aetiology of acute exacerbations in chronic obstructive pulmonary disease was investigated in patients with stable disease and in those with acute exacerbations using real-time PCR. No indication was found of a role for Legionella spp., Chlamydia pneumoniae or Mycoplasma pneumoniae in stable, moderately severe chronic obstructive pulmonary disease and in its exacerbations.

  9. Mutations that permit residual CFTR function delay acquisition of multiple respiratory pathogens in CF patients

    PubMed Central

    2010-01-01

    Background Lung infection by various organisms is a characteristic feature of cystic fibrosis (CF). CFTR genotype effects acquisition of Pseudomonas aeruginosa (Pa), however the effect on acquisition of other infectious organisms that frequently precede Pa is relatively unknown. Understanding the role of CFTR in the acquisition of organisms first detected in patients may help guide symptomatic and molecular-based treatment for CF. Methods Lung infection, defined as a single positive respiratory tract culture, was assessed for 13 organisms in 1,381 individuals with CF. Subjects were divided by predicted CFTR function: 'Residual': carrying at least one partial function CFTR mutation (class IV or V) and 'Minimal' those who do not carry a partial function mutation. Kaplan-Meier estimates were created to assess CFTR effect on age of acquisition for each organism. Cox proportional hazard models were performed to control for possible cofactors. A separate Cox regression was used to determine whether defining infection with Pa, mucoid Pa or Aspergillus (Asp) using alternative criteria affected the results. The influence of severity of lung disease at the time of acquisition was evaluated using stratified Cox regression methods by lung disease categories. Results Subjects with 'Minimal' CFTR function had a higher hazard than patients with 'Residual' function for acquisition of 9 of 13 organisms studied (HR ranging from 1.7 to 3.78 based on the organism studied). Subjects with minimal CFTR function acquired infection at a younger age than those with residual function for 12 of 13 organisms (p-values ranging: < 0.001 to 0.017). Minimal CFTR function also associated with younger age of infection when 3 alternative definitions of infection with Pa, mucoid Pa or Asp were employed. Risk of infection is correlated with CFTR function for 8 of 9 organisms in patients with good lung function (>90%ile) but only 1 of 9 organisms in those with poorer lung function (<50%ile). Conclusions

  10. Human Sentinel Surveillance of Influenza and Other Respiratory Viral Pathogens in Border Areas of Western Cambodia

    PubMed Central

    Chuang, Ilin; Samon, Nou; Uthaimongkol, Nichapat; Klungthong, Chonticha; Manasatienkij, Wudtichai; Thaisomboonsuk, Butsaya; Tyner, Stuart D.; Rith, Sareth; Horm, Viseth Srey; Jarman, Richard G.; Bethell, Delia; Chanarat, Nitima; Pavlin, Julie; Wongstitwilairoong, Tippa; Saingam, Piyaporn; El, But Sam; Fukuda, Mark M.; Touch, Sok; Sovann, Ly; Fernandez, Stefan; Buchy, Philippe; Chanthap, Lon; Saunders, David

    2016-01-01

    Little is known about circulation of influenza and other respiratory viruses in remote populations along the Thai-Cambodia border in western Cambodia. We screened 586 outpatients (median age 5, range 1–77) presenting with influenza-like-illness (ILI) at 4 sentinel sites in western Cambodia between May 2010 and December 2012. Real-time reverse transcriptase (rRT) PCR for influenza was performed on combined nasal and throat specimens followed by viral culture, antigenic analysis, antiviral susceptibility testing and full genome sequencing for phylogenetic analysis. ILI-specimens negative for influenza were cultured, followed by rRT-PCR for enterovirus and rhinovirus (EV/RV) and EV71. Influenza was found in 168 cases (29%) and occurred almost exclusively in the rainy season from June to November. Isolated influenza strains had close antigenic and phylogenetic relationships, matching vaccine and circulating strains found elsewhere in Cambodia. Influenza vaccination coverage was low (<20%). Western Cambodian H1N1(2009) isolate genomes were more closely related to 10 earlier Cambodia isolates (94.4% genome conservation) than to 13 Thai isolates (75.9% genome conservation), despite sharing the majority of the amino acid changes with the Thai references. Most genes showed signatures of purifying selection. Viral culture detected only adenovirus (5.7%) and parainfluenza virus (3.8%), while non-polio enteroviruses (10.3%) were detected among 164 culture-negative samples including coxsackievirus A4, A6, A8, A9, A12, B3, B4 and echovirus E6 and E9 using nested RT-PCR methods. A single specimen of EV71 was found. Despite proximity to Thailand, influenza epidemiology of these western Cambodian isolates followed patterns observed elsewhere in Cambodia, continuing to support current vaccine and treatment recommendations from the Cambodian National Influenza Center. Amino acid mutations at non-epitope sites, particularly hemagglutinin genes, require further investigation in light

  11. Integrated DNA and RNA extraction using magnetic beads from viral pathogens causing acute respiratory infections.

    PubMed

    He, Hui; Li, Rongqun; Chen, Yi; Pan, Ping; Tong, Wenjuan; Dong, Xueyan; Chen, Yueming; Yu, Daojun

    2017-03-23

    Current extraction methods often extract DNA and RNA separately, and few methods are capable of co-extracting DNA and RNA from sputum. We established a nucleic acid co-extraction method from sputum based on magnetic beads and optimized the method by evaluating influencing factors, such as the guanidinium thiocyanate (GTC) and dithiothreitol (DTT) concentrations, magnetic bead amount, incubation temperature, lysis buffer pH and RNA carrier type. The feasibility of the simultaneous nucleic acid co-extraction method was evaluated by amplifying DNA and RNA viruses from a single clinical specimen with a multiplex RT-qPCR method. Both DNA and RNA were most efficiently extracted when the GTC and DTT concentrations were 2.0 M and 80 mM, respectively, 20 μl magnetic beads were added, the incubation temperature was 80 °C, the pH was 8 or 9, and RNA carrier A was used. Therefore, we established a simple method to extract nucleic acids from two important respiratory viruses compared with other commercial kits. This magnetic beads-based co-extraction method for sputum followed by a multiplex RT-qPCR can rapidly and precisely detect DNA and RNA viruses from a single clinical specimen and has many advantages, such as decreased time, low cost, and a lack of harmful chemicals.

  12. Integrated DNA and RNA extraction using magnetic beads from viral pathogens causing acute respiratory infections

    PubMed Central

    He, Hui; Li, Rongqun; Chen, Yi; Pan, Ping; Tong, Wenjuan; Dong, Xueyan; Chen, Yueming; Yu, Daojun

    2017-01-01

    Current extraction methods often extract DNA and RNA separately, and few methods are capable of co-extracting DNA and RNA from sputum. We established a nucleic acid co-extraction method from sputum based on magnetic beads and optimized the method by evaluating influencing factors, such as the guanidinium thiocyanate (GTC) and dithiothreitol (DTT) concentrations, magnetic bead amount, incubation temperature, lysis buffer pH and RNA carrier type. The feasibility of the simultaneous nucleic acid co-extraction method was evaluated by amplifying DNA and RNA viruses from a single clinical specimen with a multiplex RT-qPCR method. Both DNA and RNA were most efficiently extracted when the GTC and DTT concentrations were 2.0 M and 80 mM, respectively, 20 μl magnetic beads were added, the incubation temperature was 80 °C, the pH was 8 or 9, and RNA carrier A was used. Therefore, we established a simple method to extract nucleic acids from two important respiratory viruses compared with other commercial kits. This magnetic beads-based co-extraction method for sputum followed by a multiplex RT-qPCR can rapidly and precisely detect DNA and RNA viruses from a single clinical specimen and has many advantages, such as decreased time, low cost, and a lack of harmful chemicals. PMID:28332631

  13. Emergence of a novel highly pathogenic porcine reproductive and respiratory syndrome virus in China.

    PubMed

    Liu, J-K; Zhou, X; Zhai, J-Q; Li, B; Wei, C-H; Dai, A-L; Yang, X-Y; Luo, M-L

    2017-02-14

    From 2014 to 2015, four novel highly pathogenic PRRS virus (HP-PRRSV) strains named 14LY01-FJ, 14LY02-FJ 15LY01-FJ, and 15LY02-FJ were isolated from high morbidity (100%) and mortality (40%-80%) in piglets and sows in Fujian Province. To further our knowledge about these novel virus strains, we characterized their complete genomes and determined their pathogenicity in piglets. Full-length genome sequencing analysis showed that these four isolates were closely related to type 2 (North American type, NA-type) isolates, with 88.1%-96.3% nucleotide similarity, but only 60.6%-60.8% homology to the Lelystad virus (LV) (European type, EU-type). The full length of the four isolates was determined to be 15017 or 15018 nucleotides (nt), excluding the poly(A) tail. Furthermore, the four isolates had three discontinuous deletions (aa 322-432, aa 483, and aa 504-522) within hypervariable region II (HV-II) of Nsp2, as compared to the reference strain VR-2332. This deletion pattern in the four isolates is consistent with strain MN184 and strain NADC30 isolated from America. Phylogenetic and molecular evolutionary analyses indicated that these virulent strains originated from a natural recombination event between the JXA1-like HP-PRRSV (JXA-1 is one of the earliest Chinese HP-PRRSV strains; sublineage 8.7) and the NADC30-like (lineage 1) PRRSV. Animal experiments demonstrated that these four strains caused significant weight loss and severe histopathological lung lesions as compared to the negative control group. High mortality rate (40% or 80%) was found in piglets infected with any one of the four strains, similar to that found with other Chinese HP-PRRSV strains. This study showed that the novel variant PRRSV was HP-PRRSV, and it is therefore critical to monitor PRRSV evolution in China and develop a method for controlling PRRS.

  14. Genomic Investigation into Strain Heterogeneity and Pathogenic Potential of the Emerging Gastrointestinal Pathogen Campylobacter ureolyticus

    PubMed Central

    Bullman, Susan; Lucid, Alan; Corcoran, Daniel; Sleator, Roy D.; Lucey, Brigid

    2013-01-01

    The recent detection and isolation of C. ureolyticus from patients with diarrhoeal illness and inflammatory bowel diseases warrants further investigation into its role as an emerging pathogen of the human gastrointestinal tract. Regarding the pathogenic mechanisms employed by this species we provide the first whole genome analysis of two C. ureolyticus isolates including the type strain. Comparative analysis, subtractive hybridisation and gene ontology searches against other Campylobacter species identifies the high degree of heterogenicity between C. ureolyticus isolates, in addition to the identification of 106 putative virulence associated factors, 52 of which are predicted to be secreted. Such factors encompass each of the known virulence tactics of pathogenic Campylobacter spp. including adhesion and colonisation (CadF, PEB1, IcmF and FlpA), invasion (ciaB and 16 virB-virD4 genes) and toxin production (S-layer RTX and ZOT). Herein, we provide the first virulence catalogue for C. ureolyticus, the components of which theoretically provide this emerging species with sufficient arsenal to establish pathology. PMID:24023611

  15. Pharmacodynamic and pharmacokinetic profiling of delafloxacin in a murine lung model against community-acquired respiratory tract pathogens.

    PubMed

    Thabit, Abrar K; Crandon, Jared L; Nicolau, David P

    2016-11-01

    Increasing antimicrobial resistance in community-acquired pneumonia (CAP) pathogens has contributed to infection-related morbidity and mortality. Delafloxacin is a novel fluoroquinolone with broad-spectrum activity against Gram-positive and -negative organisms, including Streptococcus pneumoniae and methicillin-resistant Staphylococcus aureus (MRSA). This study aimed to define the pharmacodynamic profile of delafloxacin against CAP pathogens using a neutropenic murine lung infection model. Five S. pneumoniae, 2 methicillin-susceptible S. aureus (MSSA), 2 MRSA and 2 Klebsiella pneumoniae isolates were studied. Delafloxacin doses varied from 0.5 mg/kg/day to 640 mg/kg/day and were given as once-daily to every 3 h regimens over the 24-h treatment period. Efficacy was measured as the change in log10 CFU at 24 h compared with 0-h controls. Plasma and bronchopulmonary pharmacokinetic studies were conducted. Delafloxacin demonstrated potent in vitro and in vivo activity. Delafloxacin demonstrated high penetration into the lung compartment, as epithelial lining fluid concentrations were substantially higher than free drug in plasma. The ratio of the area under the free drug concentration-time curve to the minimum inhibitory concentration of the infecting organism (fAUC/MIC) was the parameter that best correlated with the efficacy of the drug, and the magnitude required to achieve 1 log10 CFU reduction was 31.8, 24.7, 0.4 and 9.6 for S. pneumoniae, MRSA, MSSA and K. pneumoniae, respectively. The observed in vivo efficacy of delafloxacin was supported by the high pulmonary disposition of the compound. The results derived from this pre-clinical lung model support the continued investigation of delafloxacin for the treatment of community-acquired lower respiratory tract infections.

  16. Antibody-Based Sensors: Principles, Problems and Potential for Detection of Pathogens and Associated Toxins

    PubMed Central

    Byrne, Barry; Stack, Edwina; Gilmartin, Niamh; O'Kennedy, Richard

    2009-01-01

    Antibody-based sensors permit the rapid and sensitive analysis of a range of pathogens and associated toxins. A critical assessment of the implementation of such formats is provided, with reference to their principles, problems and potential for ‘on-site’ analysis. Particular emphasis is placed on the detection of foodborne bacterial pathogens, such as Escherichia coli and Listeria monocytogenes, and additional examples relating to the monitoring of fungal pathogens, viruses, mycotoxins, marine toxins and parasites are also provided. PMID:22408533

  17. Transcription analysis on response of porcine alveolar macrophages to co-infection of the highly pathogenic porcine reproductive and respiratory syndrome virus and Mycoplasma hyopneumoniae.

    PubMed

    Li, Bin; Du, Luping; Xu, Xiangwei; Sun, Bing; Yu, Zhengyu; Feng, Zhixin; Liu, Maojun; Wei, Yanna; Wang, Haiyan; Shao, Guoqing; He, Kongwang

    2015-01-22

    Porcine respiratory disease complex (PRDC) is of great concern economically, for swine producers worldwide. Co-infections with porcine reproductive and respiratory syndrome virus (PRRSV) and Mycoplasma hyopneumoniae (Mhp) are considered the major causative agents of PRDC, and responsible for mass mortality in pigs. Nevertheless, the molecular mechanisms underlying the host factors involved in pathogenesis and persistent infection have not been clearly established because of a lack of information regarding host responses following co-infection. In the current study, high throughput cDNA microarray assays were employed to evaluate host responses of porcine alveolar macrophages (PAM) to co-infection with highly pathogenic PRRSV (HP-PRRSV) and Mhp. A total of 2152 and 1760 genes were identified as being differentially expressed between the control group and PRRSV+Mhp co-infected group at 6 and 15 h post infection, respectively. The DE genes were involved in many vital functional classes, including inflammatory response, immune response, apoptosis, defense response, signal transduction. The pathway analysis demonstrated that the most significant pathways were associated with chemokine signaling pathway, cytokine, TLR, RLR and NLR signaling pathways and Jak-STAT signaling pathway. STRING analysis demonstrated that IL-1β is an integral gene in co-infections with PRRSV and Mhp. The present study is the first to document the response of PAMs to co-infection with HP-PRRSV and Mhp. The observed gene expression profile could help with the screening of potential host agents for reducing the prevalence of co-infections, and to further develop our understanding of the molecular pathogenesis associated with PRRSV and Mhp co-infection in pigs.

  18. Simultaneous detection of eight swine reproductive and respiratory pathogens using a novel GeXP analyser-based multiplex PCR assay.

    PubMed

    Zhang, Minxiu; Xie, Zhixun; Xie, Liji; Deng, Xianwen; Xie, Zhiqin; Luo, Sisi; Liu, Jiabo; Pang, Yaoshan; Khan, Mazhar I

    2015-11-01

    A new high-throughput GenomeLab Gene Expression Profiler (GeXP) analyser-based multiplex PCR assay was developed for the detection of eight reproductive and respiratory pathogens in swine. The reproductive and respiratory pathogens include North American porcine reproductive and respiratory syndrome virus (PRRSV-NA), classical swine fever virus (CSFV), porcine circovirus 2 (PCV-2), swine influenza virus (SIV) (including H1 and H3 subtypes), porcine parvovirus (PPV), pseudorabies virus (PRV) and Japanese encephalitis virus (JEV). Nine pairs of specific chimeric primers were designed and used to initiate PCRs, and one pair of universal primers was used for subsequent PCR cycles. The specificity of the GeXP assay was examined using positive controls for each virus. The sensitivity was evaluated using serial ten-fold dilutions of in vitro-transcribed RNA from all of the RNA viruses and plasmids from DNA viruses. The GeXP assay was further evaluated using 114 clinical specimens and was compared with real-time PCR/single RT-PCR methods. The specificity of the GeXP assay for each pathogen was examined using single cDNA/DNA template. Specific amplification peaks of the reproductive and respiratory pathogens were observed on the GeXP analyser. The minimum copies per reaction detected for each virus by the GeXP assay were as follows: 1000 copies/μl for PRV; 100 copies/μl for CSFV, JEV, PCV-2 and PPV; and 10 copies/μl for SIV-H1, SIV-H3 and PRRSV-NA. Analysis of 114 clinical samples using the GeXP assay demonstrated that the GeXP assay had comparable detection to real-time PCR/single RT-PCR. This study demonstrated that the GeXP assay is a new method with high sensitivity and specificity for the identification of these swine reproductive and respiratory pathogens. The GeXP assay may be adopted for molecular epidemiological surveys of these reproductive and respiratory pathogens in swine populations.

  19. In vitro activity of five tetracyclines and some other antimicrobial agents against four porcine respiratory tract pathogens.

    PubMed

    Pijpers, A; Van Klingeren, B; Schoevers, E J; Verheijden, J H; Van Miert, A S

    1989-09-01

    The minimal inhibitory concentrations (MIC) of five tetracyclines and ten other antimicrobial agents were determined for four porcine bacterial respiratory tract pathogens by the agar dilution method. For the following oxytetracycline-susceptible strains, the MIC50 ranges of the tetracyclines were: P. multocida (n = 17) 0.25-0.5 micrograms/ml; B. bronchiseptica (n = 20) 0.25-1.0 micrograms/ml; H. pleuropneumoniae (n = 20) 0.25-0.5 micrograms/ml; S. suis Type 2 (n = 20) 0.06-0.25 micrograms/ml. For 19 oxytetracycline-resistant P. multocida strains the MIC50 of the tetracyclines varied from 64 micrograms/ml for oxytetracycline to 0.5 micrograms/ml for minocycline. Strikingly, minocycline showed no cross-resistance with oxytetracycline, tetracycline, chlortetracycline and doxycycline in P. multocida and in H. pleuropneumoniae. Moreover, in susceptible strains minocycline showed the highest in vitro activity followed by doxycycline. Low MIC50 values were observed for chloramphenicol, ampicillin, flumequine, ofloxacin and ciprofloxacin against P. multocida and H. pleuropneumoniae. B. bronchiseptica was moderately susceptible or resistant to these compounds. As expected tiamulin, lincomycin, tylosin and spiramycin were not active against H. pleuropneumoniae. Except for flumequine, the MIC50 values of nine antimicrobial agents were low for S. suis Type 2. Six strains of this species showed resistance to the macrolides and lincomycin.

  20. Broad spectrum respiratory pathogen analysis of throat swabs from military recruits reveals interference between rhinoviruses and adenoviruses.

    PubMed

    Wang, Zheng; Malanoski, Anthony P; Lin, Baochuan; Long, Nina C; Leski, Tomasz A; Blaney, Kate M; Hansen, Christian J; Brown, Jason; Broderick, Michael; Stenger, David A; Tibbetts, Clark; Russell, Kevin L; Metzgar, David

    2010-05-01

    Military recruits experience a high incidence of febrile respiratory illness (FRI), leading to significant morbidity and lost training time. Adenoviruses, group A Streptococcus pyogenes, and influenza virus are implicated in over half of the FRI cases reported at recruit training center clinics, while the etiology of the remaining cases is unclear. In this study, we explore the carriage rates and disease associations of adenovirus, enterovirus, rhinovirus, Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitidis in military recruits using high-density resequencing microarrays. The results showed that rhinoviruses, adenoviruses, S. pneumoniae, H. influenzae, and N. meningitidis were widely distributed in recruits. Of these five agents, only adenovirus showed significant correlation with illness. Among the samples tested, only pathogens associated with FRI, such as adenovirus 4 and enterovirus 68, revealed strong temporal and spatial clustering of specific strains, indicating that they are transmitted primarily within sites. The results showed a strong negative association between adenoviral FRI and the presence of rhinoviruses in recruits, suggesting some form of viral interference.

  1. A protein secreted by the respiratory pathogen Chlamydia pneumoniae impairs IL-17 signalling via interaction with human Act1.

    PubMed

    Wolf, Katerina; Plano, Gregory V; Fields, Kenneth A

    2009-05-01

    Chlamydia pneumoniae is a common respiratory pathogen that has been associated with a variety of chronic diseases including asthma and atherosclerosis. Chlamydiae are obligate intracellular parasites that primarily infect epithelial cells where they develop within a membrane-bound vacuole, termed an inclusion. Interactions between the microorganism and eukaryotic cell can be mediated by chlamydial proteins inserted into the inclusion membrane. We describe here a novel C. pneumoniae-specific inclusion membrane protein (Inc) CP0236, which contains domains exposed to the host cytoplasm. We demonstrate that, in a yeast two-hybrid screen, CP0236 interacts with the NFκB activator 1 (Act1) and this interaction was confirmed in HeLa 229 cells where ectopically expressed CP0236 was co-immunoprecipitated with endogenous Act1. Furthermore, we demonstrate that Act1 displays an altered distribution in the cytoplasm of HeLa cells infected with C. pneumoniae where it associates with the chlamydial inclusion membrane. This sequestration of Act1 by chlamydiae inhibited recruitment of the protein to the interleukin-17 (IL-17) receptor upon stimulation of C. pneumoniae-infected cells with IL-17A. Such inhibition of the IL-17 signalling pathway led to protection of Chlamydia-infected cells from NFκB activation in IL-17-stimulated cells. We describe here a unique strategy employed by C. pneumoniae to achieve inhibition of NFκB activation via interaction of CP0236 with mammalian Act1.

  2. Propagation of field highly pathogenic porcine reproductive and respiratory syndrome virus in MARC-145 cells is promoted by cell apoptosis.

    PubMed

    Ge, Mengyun; Zhang, Yi; Liu, Ying; Liu, Tao; Zeng, Fanya

    2016-02-02

    Infection of porcine reproductive and respiratory syndrome virus (PRRSV) induces cell apoptosis both in vivo and in vitro. However, the correlation between host cell apoptosis and PRRSV replication is unclear. Here, the promotion of PRRSV propagation by cell apoptosis in MARC-145 cells was reported. The observation on propagation of field highly pathogenic PRRSV (HP-PRRSV) in MARC-145 cells showed that infection of overgrown MARC-145 cells obviously elevated virus production and cell apoptosis was triggered in these cells before virus inoculation. The investigation on propagation of field HP-PRRSV in apoptosis induced MARC-145 cells displayed that induction of apoptosis further increased the virus production and a vigorous viral RNA replication accompanied by fast virus release in these cells was detected in the initial 24h post infection. In addition, when field HP-PRRSV was serially passed in drug-treated MARC-145 cells, the progeny viruses kept a stable viral titer and infectivity to its native target cells in the tested generations. In summary, these findings demonstrated that apoptotic MARC-145 cells were more susceptible to field HP-PRRSV and propagation of the virus was promoted by effective replication and cell-to-cell transmission of the virus in these cells.

  3. Import risk assessment incorporating a dose-response model: introduction of highly pathogenic porcine reproductive and respiratory syndrome into Australia via illegally imported raw pork.

    PubMed

    Brookes, V J; Hernández-Jover, M; Holyoake, P; Ward, M P

    2014-03-01

    Highly pathogenic porcine reproductive and respiratory syndrome (PRRS) has spread through parts of south-east Asia, posing a risk to Australia. The objective of this study was to assess the probability of infection of a feral or domestic pig in Australia with highly pathogenic PRRS following ingestion of illegally imported raw pork. A conservative scenario was considered in which 500 g of raw pork was imported from the Philippines into Australia without being detected by border security, then discarded from a household and potentially accessed by a pig. Monte Carlo simulation of a two-dimensional, stochastic model was used to estimate the probability of entry and exposure, and the probability of infection was assessed by incorporating a virus-decay and mechanistic dose-response model. Results indicated that the probability of infection of a feral pig after ingestion of raw meat was higher than the probability of infection of a domestic pig. Sensitivity analysis was used to assess the influence of input parameters on model output probability estimates, and extension of the virus-decay and dose-response model was used to explore the impact of different temperatures and time from slaughter to ingestion of the meat, different weights of meat, and the level of viraemia at slaughter on the infectivity of meat. Parameters with the highest influence on the model output were the level of viraemia of a pig prior to slaughter and the probability of access by a feral pig to food-waste discarded on property surrounding a household. Extension of the decay and dose-response model showed that small pieces of meat (10 g) from a highly pathogenic PRRS viraemic pig could contain enough virus to have a high probability of infection of a pig, and that routes to Australia by sea or air from all highly pathogenic PRRS virus endemic countries were of interest dependent on the temperature of the raw meat during transport. This study highlighted the importance of mitigation strategies such

  4. Detection of feline upper respiratory tract disease pathogens using a commercially available real-time PCR test.

    PubMed

    Litster, A; Wu, C C; Leutenegger, C M

    2015-11-01

    Feline herpesvirus (FHV-1), feline calicivirus (FCV), Bordetella bronchiseptica (Bb), Chlamydia felis (Cf) and Mycoplasma felis (Mf) are common infectious agents identified in cats with upper respiratory tract disease (URTD). Each of these agents can either act as primary pathogens or cause subclinical infections, and pathogen identification can be used to prevent disease transmission in shelters, or to manage individual cats with recurrent URTD. The aim of this study was to compare pathogen detection rates using real-time PCR testing and virus isolation (VI) or bacterial culture in conjunctival, nasal and oropharyngeal swabs from 18 shelter-housed cats with clinical URTD. Co-infections were common; FHV-1 was most prevalent and Cf and FCV were least prevalent. Agents detected by PCR were FCV 2/18 (11%), FHV-1 17/18 (94%), Bb 8/18 (44%) and Mf 15/18 (83%). Agents detected by VI and bacterial culture were FCV 1/18 (6%), FHV-1 12/18 (67%), Bb 8/18 (44%) and Mf 12/18 (67%). Agreement between PCR results and the other two methods was: FHV-1, 57.4%; FCV, 98.1%; Bb, 75.0%; Mf, 60.0%. Discordancies included PCR-positive, VI-negative (FCV, n = 1/54, 1.9%; FHV-1, n = 23/54, 42.6%), PCR-positive, culture-negative (Bb, n = 6/36, 16.7%; Mf, n = 13/36, 36.1%) or PCR-negative, culture-positive (Bb, n = 3/36, 8.3%; Mf, n = 2/36, 5.6%) results. A combination of an oropharyngeal swab and either a conjunctival or a nasal swab submitted for PCR testing was able to detect all infectious agents tested for in each cat. PCR testing was a sensitive and convenient method of detection of infectious agents in cats with clinical signs of URTD.

  5. Dangerous hitchhikers? Evidence for potentially pathogenic Vibrio spp. on microplastic particles.

    PubMed

    Kirstein, Inga V; Kirmizi, Sidika; Wichels, Antje; Garin-Fernandez, Alexa; Erler, Rene; Löder, Martin; Gerdts, Gunnar

    2016-09-01

    The taxonomic composition of biofilms on marine microplastics is widely unknown. Recent sequencing results indicate that potentially pathogenic Vibrio spp. might be present on floating microplastics. Hence, these particles might function as vectors for the dispersal of pathogens. Microplastics and water samples collected in the North and Baltic Sea were subjected to selective enrichment for pathogenic Vibrio species. Bacterial colonies were isolated from CHROMagar™Vibrio and assigned to Vibrio spp. on the species level by MALDI-TOF MS (Matrix Assisted Laser Desorption/Ionisation - Time of Flight Mass Spectrometry). Respective polymers were identified by ATR FT-IR (Attenuated Total Reflectance Fourier Transform - Infrared Spectroscopy). We discovered potentially pathogenic Vibrio parahaemolyticus on a number of microplastic particles, e.g. polyethylene, polypropylene and polystyrene from North/Baltic Sea. This study confirms the indicated occurrence of potentially pathogenic bacteria on marine microplastics and highlights the urgent need for detailed biogeographical analyses of marine microplastics.

  6. Air contaminants associated with potential respiratory effects from unconventional resource development activities.

    PubMed

    McCawley, Michael

    2015-06-01

    Unconventional natural gas development uses horizontal drilling in conjunction with hydraulic fracturing to gain access to natural gas deposits which may be tightly held in shale deposits and unavailable to conventional vertical drilling operations. The intensive work required to extract this source of energy results in higher than usual numbers of vehicles involved, potential release of emissions from those vehicles in congested zones surrounding the drill site, and release of other contaminants from materials drawn back out of the borehole after fracturing of the shale. Typical contaminants would be diesel exhaust particulate and gases, volatile organic compounds and other hydrocarbons both from diesels and the drilling process, crystalline silica, used as part of the hydraulic fracturing process in kiloton quantities, and methane escaping from the borehole and piping. A rise in respiratory disease with proximity to the process has been reported in nearby communities and both silica and diesel exposures at the worksite are recognized respiratory hazards. Because of the relatively short time this process has been used to the extent it is currently being used, it is not possible to draw detailed conclusions about the respiratory hazards that may be posed. However, based on the traffic volume associated with each drill site and the number of drill sites in any locale, it is possible at least to compare the effects to that of large traffic volume highways which are known to produce some respiratory effects in surrounding areas.

  7. The Prevalence of Potential Bacterial Pathogens on Inanimate Objects in a State School

    ERIC Educational Resources Information Center

    Dandy, Tonja Denise

    2012-01-01

    Cleaning and disinfection of environmental surfaces can reduce the transmissibility of potential pathogens on school surfaces. Determining the number of bacteria and investigating the presence of pathogens on school surfaces are beginning steps in managing the well-being of students contacting those surfaces. This research study examines the…

  8. Rhizobia: a potential biocontrol agent for soilborne fungal pathogens.

    PubMed

    Das, Krishnashis; Prasanna, Radha; Saxena, Anil Kumar

    2017-03-12

    Rhizobia are a group of organisms that are well known for their ability to colonize root surfaces and form symbiotic associations with legume plants. They not only play a major role in biological nitrogen fixation but also improve plant growth and reduce disease incidence in various crops. Rhizobia are known to control the growth of many soilborne plant pathogenic fungi belonging to different genera like Fusarium, Rhizoctonia, Sclerotium, and Macrophomina. Antagonistic activity of rhizobia is mainly attributed to production of antibiotics, hydrocyanic acid (HCN), mycolytic enzymes, and siderophore under iron limiting conditions. Rhizobia are also reported to induce systemic resistance and enhance expression of plant defense-related genes, which effectively immunize the plants against pathogens. Seed bacterization with appropriate rhizobial strain leads to elicitation and accumulation of phenolic compounds, isoflavonoid phytoalexins, and activation of enzymes like L-phenylalanine ammonia lyase (PAL), chalcone synthase (CHS), peroxidase (POX), polyphenol oxidase (PPO), and others involved in phenylpropanoid and isoflavonoid pathways. Development of Rhizobium inoculants with dual attributes of nitrogen fixation and antagonism against phytopathogens can contribute to increased plant growth and productivity. This compilation aims to bring together the available information on the biocontrol facet of rhizobia and identify research gaps and effective strategies for future research in this area.

  9. Giant viruses of amoebae as potential human pathogens.

    PubMed

    Colson, Philippe; La Scola, Bernard; Raoult, Didier

    2013-01-01

    Giant viruses infecting phagocytic protists are composed of mimiviruses, the record holders of particle and genome size amongst viruses, and marseilleviruses. Since the discovery in 2003 at our laboratory of the first of these giant viruses, the Mimivirus, a growing body of data has revealed that they are common inhabitants of our biosphere. Moreover, from the outset, the story of Mimivirus has been linked to that of patients exhibiting pneumonia and it was shown that patients developed antibodies to this amoebal pathogen. Since then, there have been several proven cases of human infection or colonization with giant viruses of amoebae, which are known to host several bacteria that are human pathogens. Mimiviruses and marseilleviruses represent a major challenge in human pathology, as virological procedures implemented to date have not used appropriate media to allow their culture, and molecular techniques have used filtration steps that likely prevented their detection. Nevertheless, there is an increasing body of evidence that mimiviruses might cause pneumonia and that humans carry marseilleviruses, and re-analyses of metagenomic databases have provided evidence that these giant viruses can be common in human samples. The proportion of human infections related to these giant mimiviruses and marseilleviruses and the precise short- and long-term consequences of these infections have been scarcely investigated so far and should be the subject of future works.

  10. The Use of Predatory Bacteria to Control Select Pathogens and Treat Respiratory Infections

    DTIC Science & Technology

    2015-04-13

    clearance of Mycobacterium tuberculosis in the lungs of infected mice. PloS One 6, e17091, doi:10.1371/journal.pone.0017091 (2011). 24... infections , with many traditional antimicrobial agents becoming ineffective. An additional potential threat is the use of biological agents and...bacteria are able to serve as a novel therapeutic agent in controlling intractable bacterial infections . By co-culturing Select Agents in the presence

  11. Intercostal and forearm muscle deoxygenation during respiratory fatigue in patients with heart failure: potential role of a respiratory muscle metaboreflex.

    PubMed

    Moreno, A M; Castro, R R T; Silva, B M; Villacorta, H; Sant'Anna Junior, M; Nóbrega, A C L

    2014-11-01

    The purpose of this study was to determine the effect of respiratory muscle fatigue on intercostal and forearm muscle perfusion and oxygenation in patients with heart failure. Five clinically stable heart failure patients with respiratory muscle weakness (age, 66 ± 12 years; left ventricle ejection fraction, 34 ± 3%) and nine matched healthy controls underwent a respiratory muscle fatigue protocol, breathing against a fixed resistance at 60% of their maximal inspiratory pressure for as long as they could sustain the predetermined inspiratory pressure. Intercostal and forearm muscle blood volume and oxygenation were continuously monitored by near-infrared spectroscopy with transducers placed on the seventh left intercostal space and the left forearm. Data were compared by two-way ANOVA and Bonferroni correction. Respiratory fatigue occurred at 5.1 ± 1.3 min in heart failure patients and at 9.3 ± 1.4 min in controls (P<0.05), but perceived effort, changes in heart rate, and in systolic blood pressure were similar between groups (P>0.05). Respiratory fatigue in heart failure reduced intercostal and forearm muscle blood volume (P<0.05) along with decreased tissue oxygenation both in intercostal (heart failure, -2.6 ± 1.6%; controls, +1.6 ± 0.5%; P<0.05) and in forearm muscles (heart failure, -4.5 ± 0.5%; controls, +0.5 ± 0.8%; P<0.05). These results suggest that respiratory fatigue in patients with heart failure causes an oxygen demand/delivery mismatch in respiratory muscles, probably leading to a reflex reduction in peripheral limb muscle perfusion, featuring a respiratory metaboreflex.

  12. An Integrated Epidemiological and Economic Analysis of Vaccination against Highly Pathogenic Porcine Reproductive and Respiratory Syndrome (PRRS) in Thua Thien Hue Province, Vietnam

    PubMed Central

    Zhang, Haifeng; Kono, Hiroichi; Kubota, Satoko

    2014-01-01

    The purposes of this study are to assess pig farmers’ preference for highly pathogenic porcine reproductive and respiratory syndrome (PRRS) vaccine, and estimate the cost and benefit of PRRS vaccination in Vietnam. This study employed an integrated epidemiological and economic analysis which combined susceptible-infectious-recovered (SIR) model, choice experiment (CE) and cost-benefit analysis (CBA) together. The result of SIR model showed the basic reproduction number (R0) of PRRS transmission in this study is 1.3, consequently, the optimal vaccination percentage is 26%. The results of CE in this study indicate that Vietnam pig farmers are showing a high preference for the PRRS vaccine. However, their mean willingness to pay is lower than the potential cost of PRRS vaccine. It can be considered to be one of the reasons that the PRRS vaccination ratio is still low in Vietnam. The results of CBA specified from the whole society’s point of view (Social perspective), the benefits of PRRS vaccination are 2.3 to 4.5 times larger than the costs. To support policy making for increasing the PRRS vaccination proportion, this study indicates two ways to increase the vaccination proportion: i) decrease vaccine price by providing a subsidy, ii) provide compensation of culling only for PRRS vaccinated pigs. PMID:25178303

  13. Cryptococcus Strains with Different Pathogenic Potentials Have Diverse Protein Secretomes

    PubMed Central

    Campbell, Leona T.; Simonin, Anna R.; Chen, Cuilan; Ferdous, Jannatul; Padula, Matthew P.; Harry, Elizabeth; Hofer, Markus; Campbell, Iain L.

    2015-01-01

    Secreted proteins are the frontline between the host and pathogen. In mammalian hosts, secreted proteins enable invasive infection and can modulate the host immune response. Cryptococcosis, caused by pathogenic Cryptococcus species, begins when inhaled infectious propagules establish to produce pulmonary infection, which, if not resolved, can disseminate to the central nervous system to cause meningoencephalitis. Strains of Cryptococcus species differ in their capacity to cause disease, and the mechanisms underlying this are not well understood. To investigate the role of secreted proteins in disease, we determined the secretome for three genome strains of Cryptococcus species, including a hypovirulent and a hypervirulent strain of C. gattii and a virulent strain of C. neoformans. Sixty-seven unique proteins were identified, with different numbers and types of proteins secreted by each strain. The secretomes of the virulent strains were largely limited to proteolytic and hydrolytic enzymes, while the hypovirulent strain had a diverse secretome, including non-conventionally secreted canonical cytosolic and immunogenic proteins that have been implicated in virulence. The hypovirulent strain cannot establish pulmonary infection in a mouse model, but strains of this genotype have caused human meningitis. To directly test brain infection, we used intracranial inoculation and found that the hypovirulent strain was substantially more invasive than its hypervirulent counterpart. We suggest that immunogenic proteins secreted by this strain invoke a host response that limits pulmonary infection but that there can be invasive growth and damage if infection reaches the brain. Given their known role in virulence, it is possible that non-conventionally secreted proteins mediate this process. PMID:25841021

  14. Occurrence of Potentially Pathogenic Bacterial-Endosymbionts in Acanthamoeba Spp.

    PubMed Central

    NIYYATI, Maryam; MAFI, Mahyar; HAGHIGHI, Ali; HAKEMI VALA, Mojdeh

    2015-01-01

    Background: Acanthamoeba- bacteria interactions enable pathogenic bacteria to tolerate harsh conditions and lead to transmission to the susceptible host. The present study was aimed to address the presence of bacterial endosymbionts of Acanthamoeba isolated from recreational water sources of Tehran, Iran. To the best of our knowledge this is the first study regarding occurrence of bacteria in environmental Acanthamoeba spp. in Iran. Methods: A total of 75 samples of recreational water sources were collected. Samples were cultured on non- nutrient agar 1.5% plates. Positive Acanthamoeba spp. were axenically grown. DNA extraction and PCR reaction was performed using JDP1-2 primers. All positive samples of Acanthamoeba were examined for the presence of endosymbionts using staining and molecular methods. The PCR products were then sequenced in order to determine the genotypes of Acanthamoeba and bacteria genera. Results: Out of 75 samples, 16 (21.3%) plates were positive for Acanthamoeba according to the morphological criteria. Molecular analysis revealed that Acanthamoeba belonged to T4 and T5 genotypes. Five isolates (35.7%) were positive for bacterial endosymbionts using staining method and PCR test. Sequencing of PCR products confirmed the presence of Pseudomonas aeruginosa and Agrobacterium tumefasiens. Conclusion: The presence of Acanthamoeba bearing pathogenic endosymbionts in water sources leads us to public health issues including improved sanitation and decontamination measures in recreational water sources in order to prevent amoebae-related infection. To the best of our knowledge this is the first report regarding the isolation of A. tumefasiens from Acanthamoeba in Iran and worldwide. PMID:26246815

  15. Antimicrobial susceptibility of bacterial pathogens associated with community-acquired respiratory tract infections in Asia: report from the Community-Acquired Respiratory Tract Infection Pathogen Surveillance (CARTIPS) study, 2009-2010.

    PubMed

    Wang, Hui; Chen, Minjun; Xu, Yingchun; Sun, Hongli; Yang, Qiwen; Hu, Yunjian; Cao, Bin; Chu, Yunzhuo; Liu, Yong; Zhang, Rong; Yu, Yunsong; Sun, Ziyong; Zhuo, Chao; Ni, Yuxing; Hu, Bijie; Tan, Thean Yen; Hsueh, Po-Ren; Wang, Jen-Hsien; Ko, Wen-Chien; Chen, Yen-Hsu; Wahjono, Hendro

    2011-11-01

    A multicentre resistance surveillance study [Community-Acquired Respiratory Tract Infection Pathogen Surveillance (CARTIPS)] investigating the susceptibilities of 2963 clinical isolates of Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Klebsiella pneumoniae, meticillin-susceptible Staphylococcus aureus (MSSA) and Streptococcus spp. from Asia against 12 antimicrobial agents was undertaken from 2009 to 2010. Based on the breakpoints for oral penicillin V recommended by the Clinical and Laboratory Standards Institute, the prevalence of penicillin-non-susceptible S. pneumoniae (PNSSP) ranged from 46% to 100%. Azithromycin and clarithromycin exhibited variable resistance rates of 0-88% against S. pneumoniae, 0-57% against MSSA and 0-76.5% against Streptococcus spp. isolates. The prevalence of extended-spectrum β-lactamase-producing K. pneumoniae varied from 5.1% to 58.5%. β-Lactamase production rates amongst H. influenzae isolates ranged from 15% to 46.6% and amongst M. catarrhalis isolates from 90% to 100%. Amongst M. catarrhalis isolates, macrolide resistance and cefaclor resistance rates of 5.8% and 1.2%, respectively, were found, mainly in Mainland China. Levofloxacin resistance rates of 0-3.9% with a MIC(90) (minimum inhibitory concentration causing inhibition of 90% of isolates) of 1-2mg/L and moxifloxacin resistance rates of 0-1.7% with a MIC(90) of 0.125-0.5mg/L were found amongst PNSSP isolates. Moxifloxacin was very active against Streptococcus spp., H. influenzae and M. catarrhalis isolates, with MIC(90) values of 0.125-0.25, 0.032-0.5 and 0.064-0.125mg/L, respectively. These results from the CARTIPS study have confirmed some significant regional differences in the antimicrobial susceptibilities of S. pneumoniae, MSSA, K. pneumoniae, H. influenzae and Streptococcus spp. and emphasise the importance of antimicrobial surveillance programmes for guiding empirical therapy and for focusing interventional control of antimicrobial

  16. Comparison between acute oral/respiratory and chronic stomatitis/gingivitis isolates of feline calicivirus: pathogenicity, antigenic profile and cross-neutralisation studies.

    PubMed

    Poulet, H; Brunet, S; Soulier, M; Leroy, V; Goutebroze, S; Chappuis, G

    2000-01-01

    Feline calicivirus (FCV) is a major oral and respiratory pathogen of cats, able to induce subclinical infection as well as acute disease. It is also characterized by a high degree of antigenic variation. This work sought to address the question of the existence of distinct biotypes of FCV. Eight French, 6 British and 9 American FCV isolates, responsible for acute oral/respiratory disease or chronic gingivitis/stomatitis, were compared for their pathogenicity, antigenic profiles and serological relationships. Antigenic profiles were assessed by an indirect immunofluorescence assay with a large panel of characterized monoclonal antibodies. Cross-neutralisation assays were performed with specific cat antisera collected at 30 days p.i., then analysed by calculation of antigenic bilateral relatedness and dominance. Whatever their pathogenic origin, all the isolates induced an acute upper-respiratory tract infection in oronasally infected SPF kittens. Their antigenic profiles were different and did not correlate with their geographical or pathological origin. Cross-neutralisation studies and calculation of the mean bilateral relatedness allowed us to distinguish chronic original isolates from acute original ones. This study did not confirm the existence of FCV biotypes but showed that the chronic carrier state is related to the emergence of antigenically distant viruses.

  17. The potential of methylxanthine-based therapies in pediatric respiratory tract diseases.

    PubMed

    Oñatibia-Astibia, Ainhoa; Martínez-Pinilla, Eva; Franco, Rafael

    2016-03-01

    Caffeine, theophylline and theobromine are the most known methylxanthines as they are present in coffee, tea and/or chocolate. In the last decades, a huge experimental effort has been devoted to get insight into the variety of actions that these compounds exert in humans. From such knowledge it is known that methylxanthines have a great potential in prevention, therapy and/or management of a variety of diseases. The benefits of methylxanthine-based therapies in the apnea of prematurity and their translational potential in pediatric affections of the respiratory tract are here presented.

  18. Rare occurrence of heterotrophic bacteria with pathogenic potential in potable water.

    PubMed

    Stelma, Gerard N; Lye, Dennis J; Smith, Bennett G; Messer, James W; Payment, Pierre

    2004-05-01

    Since the discovery of Legionella pneumophila, an opportunistic pathogen that is indigenous to water, microbiologists have speculated that there may be other opportunistic pathogens among the numerous heterotrophic bacteria found in potable water. The US Environmental Protection Agency (USEPA) developed a series of rapid in vitro assays to assess the virulence potential of large numbers of bacteria from potable water to possibly identify currently unknown pathogens. Results of surveys of potable water from several distribution systems using these tests showed that only 50 of the approximately 10,000 bacterial colonies expressed one or more virulence characteristics. In another study, 45 potable water isolates that expressed multiple virulence factors were tested for pathogenicity in immunocompromised mice. None of the isolates infected mice that were compromised either by treatment with carrageenan (CG), to induce susceptibility to facultative intracellular pathogens, or by cyclophosphamide (CY), to induce susceptibility to extracellular pathogens. These results indicate that there are very few potential pathogens in potable water and that the currently developed in vitro virulence screening tests give an overestimation of the numbers of heterotrophic bacteria that may be pathogens. Current efforts are focused on using the animal models to screen concentrated samples of waters known to contain large numbers of heterotrophic bacteria and newly discovered Legionella-like organisms that parasitize amoebae.

  19. Microbial antagonism as a potential solution for controlling selected root pathogens of crops

    NASA Astrophysics Data System (ADS)

    Cooper, Sarah; Agnew, Linda; Pereg, Lily

    2016-04-01

    Root pathogens of crops can cause large reduction in yield, however, there is a limited range of effective methods to control such pathogens. Soilborne pathogens that infect roots often need to survive in the rhizosphere, where there is high competition from other organisms. In such hot spots of microbial activity and growth, supported by root exudates, microbes have evolved antagonistic mechanisms that give them competitive advantages in winning the limited resources. Among these mechanisms is antibiosis, with production of some significant antifungal compounds including, antibiotics, volatile organic compounds, hydrogen cyanide and lytic enzymes. Some of these mechanisms may suppress disease through controlling the growth of root pathogens. In this project we isolated various fungi and bacteria that suppress the growth of cotton pathogens in vitro. The pathogen-suppressive microbes were isolated from cotton production soils that are under different management strategies, with and without the use of organic amendments. The potential of pathogen-suppressing microbes for controlling the black root rot disease, caused by the soilborne pathogen Thielaviopsis basicola, was confirmed using soil assays. We identified isolates with potential use as inoculant for cotton production in Australia. Having isolated a diverse group of antagonistic microbes enhances the probability that some would survive well in the soil and provide an alternative approach to address the problem of root disease affecting agricultural crops.

  20. Prediction and validation of potential pathogenic microRNAs involved in Phytophthora infestans infection.

    PubMed

    Cui, Juanjuan; Luan, Yushi; Wang, Weichen; Zhai, Junmiao

    2014-03-01

    Being one kind of approximately 22nt long small RNA, miRNA has shown its roles in host-pathogen interaction, providing one possible way for pathogen infection. Though Phytophthora infestans is a major pathogen that causes devastating late blight of potato, tomato and so on, so far there have not been any systematic researches on miRNAs and even pathogenic miRNAs in P. infestans. Here, for the first time we comprehensively predicted and identified pathogenic miRNAs that may exist in P. infestans. First, a total of 128 putative miRNAs belonging to 66 miRNA family were identified by bioinformatic approaches. Then, 33 vital pathogenic miRNAs were screened by constructing miRNA-miRNA relationship networks. Finally, four potential pathogenic miRNAs were chosen for detection, two of which are chosen for validation. The expression quantity of pi-miR466 and pi-miR1918 changed dramatically during incubation of tomato leaves, implying that they are potential pathogenic miRNAs.

  1. Increased pathogenicity of European porcine reproductive and respiratory syndrome virus is associated with enhanced adaptive responses and viral clearance.

    PubMed

    Morgan, S B; Graham, S P; Salguero, F J; Sánchez Cordón, P J; Mokhtar, H; Rebel, J M J; Weesendorp, E; Bodman-Smith, K B; Steinbach, F; Frossard, J P

    2013-04-12

    Porcine reproductive and respiratory syndrome (PRRS) is one of the most economically important diseases of swine worldwide. Since its first emergence in 1987 the PRRS virus (PRRSV) has become particularly divergent with highly pathogenic strains appearing in both Europe and Asia. However, the underlying mechanisms of PRRSV pathogenesis are still unclear. This study sets out to determine the differences in pathogenesis between subtype 1 and 3 strains of European PRRSV (PRRSV-I), and compare the immune responses mounted against these strains. Piglets were infected with 3 strains of PRRSV-I: Lelystad virus, 215-06 a British field strain and SU1-bel from Belarus. Post-mortem examinations were performed at 3 and 7 days post-infection (dpi), and half of the remaining animals in each group were inoculated with an Aujeszky's disease (ADV) vaccine to investigate possible immune suppression resulting from PRRSV infection. The subtype 3 SU1-bel strain displayed greater clinical signs and lung gross pathology scores compared with the subtype 1 strains. This difference did not appear to be caused by higher virus replication, as viraemia and viral load in broncho-alveolar lavage fluid (BALF) were lower in the SU1-bel group. Infection with SU1-bel induced an enhanced adaptive immune response with greater interferon (IFN)-γ responses and an earlier PRRSV-specific antibody response. Infection with PRRSV did not affect the response to vaccination against ADV. Our results indicate that the increased clinical and pathological effect of the SU1-bel strain is more likely to be caused by an enhanced inflammatory immune response rather than higher levels of virus replication.

  2. Assessment of the efficacy of two novel DNA vaccine formulations against highly pathogenic Porcine Reproductive and Respiratory Syndrome Virus

    PubMed Central

    Du, Luping; Pang, Fengjiao; Yu, Zhengyu; Xu, Xiangwei; Fan, Baochao; Huang, Kehe; He, Kongwang; Li, Bin

    2017-01-01

    Since May 2006, a highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) has emerged and prevailed in mainland China, affecting over 2 million pigs. Commercial PRRSV killed and modified live vaccines cannot provide complete protection against HP-PRRSV due to genetic variation. Development of more effective vaccines against the emerging HP-PRRSV is urgently required. In our previous studies, two formulations of DNA vaccines (pcDNA3.1-PoIFN-λ1-SynORF5 and BPEI/PLGA-SynORF5) based on the HP-PRRSV were constructed and shown to induce enhanced humoral and cellular immune responses in mice. The objective of this study was to evaluate the immune response induced by these novel formulations in piglets. PcDNA3.1-PoIFN-λ1-SynORF5 and BPEI/PLGA-SynORF5 vaccines induced significantly enhanced GP5-specific antibody and PRRSV-specific neutralizing antibody in pigs compared with the pcDNA3.1-SynORF5 parental construct. Though IFN-γ levels and lymphocyte proliferation responses induced by the two DNA vaccine formulations were comparable to that induced by the pcDNA3.1-SynORF5 construct, each of the novel formulations provided efficient protection against challenge with HP-PRRSV. Non-severe clinical signs and rectal temperatures were observed in pigs immunized with BPEI/PLGA-SynORF5 compared with other groups. Thus, these novel DNA constructs may represent promising candidate vaccines against emerging HP-PRRSV. PMID:28157199

  3. A Novel Method and Its Application to Measuring Pathogen Decay in Bioaerosols from Patients with Respiratory Disease

    PubMed Central

    Knibbs, Luke D.; Kidd, Timothy J.; Wainwright, Claire E.; Wood, Michelle E.; Ramsay, Kay A.; Bell, Scott C.; Morawska, Lidia

    2016-01-01

    This work aimed to develop an in vivo approach for measuring the duration of human bioaerosol infectivity. To achieve this, techniques designed to target short-term and long-term bioaerosol aging, were combined in a tandem system and optimized for the collection of human respiratory bioaerosols, without contamination. To demonstrate the technique, cough aerosols were sampled from two persons with cystic fibrosis and chronic Pseudomonas aeruginosa infection. Measurements and cultures from aerosol ages of 10, 20, 40, 900 and 2700 seconds were used to determine the optimum droplet nucleus size for pathogen transport and the airborne bacterial biological decay. The droplet nuclei containing the greatest number of colony forming bacteria per unit volume of airborne sputum were between 1.5 and 2.6 μm. Larger nuclei of 3.9 μm, were more likely to produce a colony when impacted onto growth media, because the greater volume of sputum comprising the larger droplet nuclei, compensated for lower concentrations of bacteria within the sputum of larger nuclei. Although more likely to produce a colony, the larger droplet nuclei were small in number, and the greatest numbers of colonies were instead produced by nuclei from 1.5 to 5.7 μm. Very few colonies were produced by smaller droplet nuclei, despite their very large numbers. The concentration of viable bacteria within the dried sputum comprising the droplet nuclei exhibited an orderly dual decay over time with two distinct half-lives. Nuclei exhibiting a rapid biological decay process with a 10 second half-life were quickly exhausted, leaving only a subset characterized by a half-life of greater than 10 minutes. This finding implied that a subset of bacteria present in the aerosol was resistant to rapid biological decay and remained viable in room air long enough to represent an airborne infection risk. PMID:27388489

  4. Inhibition of highly pathogenic porcine reproductive and respiratory syndrome virus replication by recombinant pseudorabies virus-mediated RNA interference in piglets.

    PubMed

    Cao, Su-fang; Guo, Qing-yong; Wang, Yan

    2015-12-31

    Highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) is a variant of porcine reproductive and respiratory syndrome virus (PRRSV) which, in recent years, has caused heavy economic losses to swine-producing areas. Although current vaccines are somewhat prophylactic, they provide only limited protection. Furthermore, there are currently no effective anti-HP-PRRSV drugs. Consequently, it is necessary to develop novel antiviral strategies. In the present study, three recombinant pseudorabies viruses (PRV) expressing siRNAs against the ORF7 of HP-PRRSV strain HN1 (PRV gG-/siRNAN1, PRV gG-/siRNAN2, and PRV gG-/siRNAN3) were evaluated for the inhibition of HP-PRRSV replication. The results indicated that recombinant PRV-mediated siRNA could significantly decrease the replication of traditional PRRSV strain H1 at mRNA and protein levels in Marc-145 cells. Moreover, one recombinant PRV (PRV gG-/siRNAN2) was found to be inhibit the multiplication of HP-PRRSV strain HN1 effectively in Marc-145 cells at both the protein and ORF7 mRNA level. Twenty 21-day-old healthy weaned piglets were divided into four groups of five piglets each. Groups 1 and 2 were injected i.m. with PRV gG-/siRNAN2 and PRV gG-/siRNANeg individually. The piglets in group 3 were challenged with the HP-PRRSV control. After 24h, the piglets in groups 1-3 were challenged i.m. with HP-PRRSV strain HN1, while those in group 4 were i.m. administered with PBS as a negative control. The results showed that HP-PRRSV in serum and lung samples from piglets was effectively inhibited by PRV gG-/siRNAN2. The clinical signs and gross lesions of piglets inoculated with PRV gG-/siRNAN2 were significantly less invasive than those of the PRV gG-/siRNANeg group and HP-PRRSV control group. These results showed that siRNAs mediated by recombinant PRV could effectively suppress HP-PRRSV replication in vitro as well as in vivo. RNAi mediated by recombinant PRV presents a potential novel method to prevent

  5. Investigation of potentially pathogenic Clostridium difficile contamination in household environs.

    PubMed

    Alam, M Jahangir; Anu, Ananna; Walk, Seth T; Garey, Kevin W

    2014-06-01

    As Clostridium difficile spores are resistant to many household cleaning products, the potential for community household contamination is high. The purpose of this study was to assess the prevalence of toxigenic C. difficile from environmental sources from a large urban area. Three to 5 household items or environmental dust was collected from 30 houses in Houston, Texas. A total of 127 environmental samples were collected from shoe bottoms (n = 63), bathroom surfaces (n = 15), house floor dusts (n = 12), or other household surfaces (n = 37). Forty one of 127 samples (32.3%) grew C. difficile. All 41 isolates were positive for toxin A and B genes and no isolate was positive for binary toxin genes. Shoe bottom swab samples had the highest percent of positive samples (25/63; 39.7%) followed by bathroom/toilet surfaces (5/15; 33.3%), house floor dust (4/12; 33.3%), and other surface swabs (7/37; 18.9%). Strains were grouped into 25 different ribotypes, the most prevalent type was 001 (5 strains). In conclusion, a high rate of environmental contamination of C. difficile was observed from community households from a large urban area.

  6. Genomics and Comparative Genomic Analyses Provide Insight into the Taxonomy and Pathogenic Potential of Novel Emmonsia Pathogens

    PubMed Central

    Yang, Ying; Ye, Qiang; Li, Kang; Li, Zongwei; Bo, Xiaochen; Li, Zhen; Xu, Yingchun; Wang, Shengqi; Wang, Peng; Chen, Huipeng; Wang, Junzhi

    2017-01-01

    adaptations of new Emmonsia, but this question warrants further investigation. Overall, our analyses provide a framework from which to further study the evolutionary dynamics of Emmonsia strains and identity the underlying molecular mechanisms that determine the infectious and pathogenic potency of these fungal pathogens, and also provide insight into potential targets for therapeutic intervention of emmonsiosis and further research.

  7. Experience with a mouse intranasal test for the predictive identification of respiratory sensitization potential of proteins.

    PubMed

    Blaikie, L; Basketter, D A

    1999-08-01

    The predictive identification of respiratory allergenic potential is an important primary step in the safety evaluation of (novel) proteins, such as the enzymes used in a range of consumer laundry products. In the past this has been achieved by assessing the relative ability of proteins to give rise to the formation of anaphylactic antibody in the guinea pig. Recently, an alternative model has been proposed which assesses the formation of specific IgG1 antibody in a mouse intranasal test (MINT), the assumption being that specific IgG1 antibody is a surrogate for anaphylactic antibody in the mouse. This procedure has undergone successful initial intralaboratory and interlaboratory assessment. In the present work, the MINT has been evaluated in a more thorough intralaboratory study using eight enzymes plus ovalbumin. While the data generated with a reference enzyme protein, Alcalase, showed good reproducibility, results with the remaining eight proteins led to estimates of their relative antigenic or sensitization potential several of which were at variance from those derived from the guinea pig/ human experience. In consequence, it is concluded that the MINT requires substantial further investigation before it can be adopted as a model for the assessment of the relative ability of proteins to behave as respiratory allergens.

  8. Potential for the International Spread of Middle East Respiratory Syndrome in Association with Mass Gatherings in Saudi Arabia

    PubMed Central

    Khan, Kamran; Sears, Jennifer; Hu, Vivian Wei; Brownstein, John S; Hay, Simon; Kossowsky, David; Eckhardt, Rose; Chim, Tina; Berry, Isha; Bogoch, Isaac; Cetron, Martin

    2013-01-01

    Background: A novel coronavirus (MERS-CoV) causing severe, life-threatening respiratory disease has emerged in the Middle East at a time when two international mass gatherings in Saudi Arabia are imminent. While MERS-CoV has already spread to and within other countries, these mass gatherings could further amplify and/or accelerate its international dissemination, especially since the origins and geographic source of the virus remain poorly understood. Methods: We analyzed 2012 worldwide flight itinerary data and historic Hajj pilgrim data to predict population movements out of Saudi Arabia and the broader Middle East to help cities and countries assess their potential for MERS-CoV importation. We compared the magnitude of travel to countries with their World Bank economic status and per capita healthcare expenditures as surrogate markers of their capacity for timely detection of imported MERS-CoV and their ability to mount an effective public health response. Results: 16.8 million travelers flew on commercial flights out of Saudi Arabia, Jordan, Qatar, and the United Arab Emirates between June and November 2012, of which 51.6% were destined for India (16.3%), Egypt (10.4%), Pakistan (7.8%), the United Kingdom (4.3%), Kuwait (3.6%), Bangladesh (3.1%), Iran (3.1%) and Bahrain (2.9%). Among the 1.74 million foreign pilgrims who performed the Hajj last year, an estimated 65.1% originated from low and lower-middle income countries. Conclusion: MERS-CoV is an emerging pathogen with pandemic potential with its apparent epicenter in Saudi Arabia, where millions of pilgrims will imminently congregate for two international mass gatherings. Understanding global population movements out of the Middle East through the end of this year's Hajj could help direct anticipatory MERS-CoV surveillance and public health preparedness to mitigate its potential global health and economic impacts. PMID:23884087

  9. Contribution of Ca2+-dependent conductances to membrane potential fluctuations of medullary respiratory neurons of newborn rats in vitro.

    PubMed

    Onimaru, Hiroshi; Ballanyi, Klaus; Homma, Ikuo

    2003-11-01

    Ca2+-dependent conductances were studied in respiratory interneurons in the brainstem-spinal cord preparation of newborn rats. omega-Conotoxin-GVIA attenuated evoked postsynaptic potentials, spontaneous or evoked inspiratory spinal nerve activity and blocked spike afterhyperpolarization. Furthermore, omega-conotoxin-GVIA augmented rhythmic drive potentials of pre-inspiratory and inspiratory neurons and increased respiratory-related spike frequency of pre-inspiratory cells with no effect on inspiratory hyperpolarization. In contrast, omega-agatoxin-IVA depressed drive potentials of pre-inspiratory and inspiratory neurons and attenuated inspiratory hyperpolarization and spike frequency of pre-inspiratory cells. It did not affect spike shape and exerted only minor, non-significant, attenuating effects on spontaneous or evoked nerve bursts or evoked postsynaptic potentials. Nifedipine diminished drive potentials and spike frequency of pre-inspiratory neurons and shortened drive potentials in some cells. omega-Conotoxin-MVIIC attenuated drive potentials and intraburst firing rate of pre-inspiratory neurons and decreased substantially respiratory frequency. Respiratory rhythm disappeared following combined application of omega-conotoxin-GVIA, omega-conotoxin-MVIIC, omega-agatoxin-IVA and nifedipine. Apamin potentiated drive potentials and abolished spike afterhyperpolarization, whereas charybdotoxin and tetraethylammonium prolonged spike duration without effect on shape of drive potentials. The results show that specific sets of voltage-activated L-, N- and P/Q-type Ca2+ channels determine the activity of particular subclasses of neonatal respiratory neurons, whereas SK- and BK-type K+ channels attenuate drive potentials and shorten spikes, respectively, independent of cell type. We hypothesize that modulation of spontaneous activity of pre-inspiratory neurons via N-, L- and P/Q-type Ca2+ channels is important for respiratory rhythm or pattern generation.

  10. Neighborhood diversity of potentially pathogenic bacteria in drinking water from the city of Maroua, Cameroon.

    PubMed

    Healy-Profitós, Jessica; Lee, Seungjun; Mouhaman, Arabi; Garabed, Rebecca; Moritz, Mark; Piperata, Barbara; Lee, Jiyoung

    2016-06-01

    This study examined the spatial variation of potential gastrointestinal pathogens within drinking water sources and home storage containers in four neighborhoods in Maroua, Cameroon. Samples were collected from source (n = 28) and home containers (n = 60) in each study neighborhood. Pathogen contamination was assessed using quantitative polymerase chain reaction, targeting Campylobacter spp., Shiga toxin producing Escherichia coli (virulence genes, stx1 and stx2), and Salmonella spp. Microbial source tracking (MST) targeted three different host-specific markers: HF183 (human), Rum2Bac (ruminant) and GFD (poultry) to identify contamination sources. Staphylococcus aureus and the tetracycline-resistance gene (tetQ) were assessed to measure human hand contact and presence of antibiotic-resistant bacteria. Pathogen/MST levels were compared statistically and spatially, and neighborhood variation was compared with previously collected demographic information. All the test fecal markers and pathogens (except Arcobacter) were detected in home and source samples. Two neighborhoods tested positive for most pathogens/MST while the others only tested positive for one or two. Spatial variation of pathogens/MST existed between sources, storage containers, and neighborhoods. Differing population density and ethno-economic characteristics could potentially explain variation. Future research should explore the influence of demographic and ethno-economic factors on water quality during microbial risk assessments in urban Africa.

  11. Foliar endophytic fungi as potential protectors from pathogens in myrmecophytic Acacia plants

    PubMed Central

    González-Teuber, Marcia; Jiménez-Alemán, Guillermo H; Boland, Wilhelm

    2014-01-01

    In defensive ant-plant interactions myrmecophytic plants express reduced chemical defense in their leaves to protect themselves from pathogens, and it seems that mutualistic partners are required to make up for this lack of defensive function. Previously, we reported that mutualistic ants confer plants of Acacia hindsii protection from pathogens, and that the protection is given by the ant-associated bacteria. Here, we examined whether foliar endophytic fungi may potentially act as a new partner, in addition to mutualistic ants and their bacteria inhabitants, involved in the protection from pathogens in myrmecophytic Acacia plants. Fungal endophytes were isolated from the asymptomatic leaves of A. hindsii plants for further molecular identification of 18S rRNA gene. Inhibitory effects of fungal endophytes were tested against Pseudomonas plant pathogens. Our findings support a potential role of fungal endophytes in pathogen the protection mechanisms against pathogens in myrmecophytic plants and provide the evidence of novel fungal endophytes capable of biosynthesizing bioactive metabolites. PMID:26843901

  12. The poultry red mite (Dermanyssus gallinae): a potential vector of pathogenic agents.

    PubMed

    Valiente Moro, Claire; De Luna, Carlos J; Tod, Alexander; Guy, Jonathan H; Sparagano, Olivier A E; Zenner, Lionel

    2009-06-01

    The poultry red mite, D. gallinae has been involved in the transmission of many pathogenic agents, responsible for serious diseases both in animals and humans. Nowadays, few effective methods are available to control the ectoparasite in poultry farms. Consequently, this is an emerging problem which must be taken into account to maintain good health in commercial egg production. This paper addresses the vector capacity of the ectoparasite with special emphasis on salmonellae, pathogenic agents responsible for many of the most important outbreaks of food-borne diseases worlwide. It has been experimentally shown that D. gallinae could act as a biological vector of S. enteritidis and natural carriage of these bacteria by the mite on poultry premises has also been reported. It was also found that D. gallinae carried other pathogens such as E. coli, Shigella sp., and Staphylococcus, thus increasing the list of pathogenic agents potentially transmitted by the mite.

  13. Respiratory-gated electrical impedance tomography: a potential technique for quantifying stroke volume

    NASA Astrophysics Data System (ADS)

    Arshad, Saaid H.; Murphy, Ethan K.; Halter, Ryan J.

    2016-03-01

    Telemonitoring is becoming increasingly important as the proportion of the population living with cardiovascular disease (CVD) increases. Currently used health parameters in the suite of telemonitoring tools lack the sensitivity and specificity to accurately predict heart failure events, forcing physicians to play a reactive versus proactive role in patient care. A novel cardiac output (CO) monitoring device is proposed that leverages a custom smart phone application and a wearable electrical impedance tomography (EIT) system. The purpose of this work is to explore the potential of using respiratory-gated EIT to quantify stroke volume (SV) and assess its feasibility using real data. Simulations were carried out using the 4D XCAT model to create anatomically realistic meshes and electrical conductivity profiles representing the human thorax and the intrathoracic tissue. A single 5-second period respiration cycle with chest/lung expansion was modeled with end-diastole (ED) and end-systole (ES) heart volumes to evaluate how effective EIT-based conductivity changes represent clinically significant differences in SV. After establishing a correlation between conductivity changes and SV, the applicability of the respiratory-gated EIT was refined using data from the PhysioNet database to estimate the number of useful end-diastole (ED) and end-systole (ES) heart events attained over a 3.3 minute period. The area associated with conductivity changes was found to correlate to SV with a correlation coefficient of 0.92. A window of 12.5% around peak exhalation was found to be the optimal phase of the respiratory cycle from which to record EIT data. Within this window, ~47 useable ED and ES were found with a standard deviation of 28 using 3.3 minutes of data for 20 patients.

  14. Potential toxicity and safety evaluation of nanomaterials for the respiratory system and lung cancer

    PubMed Central

    Vlachogianni, Thomais; Fiotakis, Konstantinos; Loridas, Spyridon; Perdicaris, Stamatis; Valavanidis, Athanasios

    2013-01-01

    Engineered nanomaterials (ENMs) are a diverse group of materials finding increasing use in manufacturing, computing, food, pharmaceuticals, and biomedicine due to their very small size and exceptional properties. Health and safety concerns for ENMs have forced regulatory agencies to consider preventive measures and regulations for workers’ health and safety protection. Respiratory system toxicity from inhalable ENMs is the most important concern to health specialists. In this review, we focus on similarities and differences between conventional microparticles (diameters in mm and μm), which have been previously studied, and nanoparticles (sizes between 1 and 100 nm) in terms of size, composition, and mechanisms of action in biological systems. In past decades, respirable particulate matter (PM), asbestos fibers, crystalline silicate, and various amorphous dusts have been studied, and epidemiological evidence has shown how dangerous they are to human health, especially from exposure in working environments. Scientific evidence has shown that there is a close connection between respirable PM and pulmonary oxidative stress through the generation of reactive oxygen species (ROS) and reactive nitrogen species (RNS). There is a close connection between oxidative stress in the cell and the elicitation of an inflammatory response via pro-inflammatory gene transcription. Inflammatory processes increase the risk for lung cancer. Studies in vitro and in vivo in the last decade have shown that engineered nanoparticles (ENPs) at various doses can cause ROS generation, oxidative stress, and pro-inflammatory gene expression in the cell. It is assumed that ENPs have the potential to cause acute respiratory diseases and probably lung cancer in humans. The situation regarding chronic exposure at low doses is more complicated. The long-term accumulation of ENPs in the respiratory system cannot be excluded. However, at present, exposure data for the general public regarding ENPs

  15. Bacteria isolated from parasitic nematodes--a potential novel vector of pathogens?

    PubMed

    Lacharme-Lora, Lizeth; Salisbury, Vyv; Humphrey, Tom J; Stafford, Kathryn; Perkins, Sarah E

    2009-12-21

    Bacterial pathogens are ubiquitous in soil and water - concurrently so are free-living helminths that feed on bacteria. These helminths fall into two categories; the non-parasitic and the parasitic. The former have been the focus of previous work, finding that bacterial pathogens inside helminths are conferred survival advantages over and above bacteria alone in the environment, and that accidental ingestion of non-parasitic helminths can cause systemic infection in vertebrate hosts. Here, we determine the potential for bacteria to be associated with parasitic helminths. After culturing helminths from fecal samples obtained from livestock the external bacteria were removed. Two-hundred parasitic helminths from three different species were homogenised and the bacteria that were internal to the helminths were isolated and cultured. Eleven different bacterial isolates were found; of which eight were indentified. The bacteria identified included known human and cattle pathogens. We concluded that bacteria of livestock can be isolated in parasitic helminths and that this suggests a mechanism by which bacteria, pathogenic or otherwise, can be transmitted between individuals. The potential for helminths to play a role as pathogen vectors poses a potential livestock and human health risk. Further work is required to assess the epidemiological impact of this finding.

  16. Potential impact of climate variability on respiratory diseases in infant and children in Semarang

    NASA Astrophysics Data System (ADS)

    Budiyono; Rismawati; Jati, S. P.; Ginandjar, P.

    2017-02-01

    Temperature, humidity, and rainfall may influence respiratory disease, including acute respiratory infection (ARI) and pneumonia. In Semarang, the temperature and humidity has increased 0.1°C and 1.6% respectively during 2002-2011. ARI and pneumonia in children under 5 years had increased during 2012-2014. This study aimed to analyze the relationship of climate variability and ARI and pneumonia incidence. It was an ecological study. Subject consisted of patients visited primary health care of Bandarharjo from 2011 to 2015. Pneumonia was related to infants (<1-year-old) and children (1-4 years old), while ARI was related to children (≥5 years old). Data of climate was obtained from Agency for Meteorology, Climatology and Geophysics (BMKG) Semarang. Pearson correlation (α=0.05) was used to analyse the correlation of the 60 samples. Mean of temperature was 27.96° C, relative humidity was 74.73%, and rainfall was 179.98 mm/month. The total of ARI was 38523 cases and pneumonia was 1558 cases. Temperature, humidity, and rainfall had no correlation to pneumonia. Humidity had a significant correlation to ARI on female children and total ARI (r=0.3 and r=0.26; p–value=0.02 and 0.04 respectively). Rainfall and temperature had no correlation to total ARI. This study concluded humidity has potential impact to ARI.

  17. Voriconazole as a first-line treatment against potentially pathogenic Acanthamoeba strains from Peru.

    PubMed

    Cabello-Vílchez, Alfonso Martín; Martín-Navarro, Carmen M; López-Arencibia, Atteneri; Reyes-Batlle, María; Sifaoui, Ines; Valladares, Basilio; Piñero, José E; Lorenzo-Morales, Jacob

    2014-02-01

    Pathogenic strains of Acanthamoeba genus are the causative agents of fatal granulomatous amoebic encephalitis and a serious sight-threatening infection of the eye known as Acanthamoeba keratitis. In a previous study, Acanthamoeba strains were isolated from nasal swabs collected from healthy individuals in Peru. In the present study, the pathogenic potential of the isolated strains was established based on temperature and osmotolerance assays as well as the secretion rate of extracellular proteases. Based on these experiments, four strains that showed the highest pathogenic potential were selected for sensitivity assays against two molecules (voriconazole and chlorhexidine) which are currently used for the treatment of Acanthamoeba infections. After performing sensitivity and activity assays, it was found that both drugs were active against the tested strains. However, voriconazole showed higher activity against the studied strains compared to chlorhexidine. Therefore, voriconazole should be established as a first-line treatment against Acanthamoeba infections at least in the studied region of Peru.

  18. Isolation and characterization of soil Streptomyces species as potential biological control agents against fungal plant pathogens.

    PubMed

    Evangelista-Martínez, Zahaed

    2014-05-01

    The use of antagonist microorganisms against fungal plant pathogens is an attractive and ecologically alternative to the use of chemical pesticides. Streptomyces are beneficial soil bacteria and potential candidates for biocontrol agents. This study reports the isolation, characterization and antagonist activity of soil streptomycetes from the Los Petenes Biosphere Reserve, a Natural protected area in Campeche, Mexico. The results showed morphological, physiological and biochemical characterization of six actinomycetes and their inhibitory activity against Curvularia sp., Aspergillus niger, Helminthosporium sp. and Fusarium sp. One isolate, identified as Streptomyces sp. CACIS-1.16CA showed the potential to inhibit additional pathogens as Alternaria sp., Phytophthora capsici, Colletotrichum sp. and Rhizoctonia sp. with percentages ranging from 47 to 90 %. This study identified a streptomycete strain with a broad antagonist activity that could be used for biocontrol of plant pathogenic fungi.

  19. Shoe soles as a potential vector for pathogen transmission: a systematic review.

    PubMed

    Rashid, T; VonVille, H M; Hasan, I; Garey, K W

    2016-11-01

    Shoe soles are possible vectors for infectious diseases. Although studies have been performed to assess the prevalence of infectious pathogens on shoe soles and decontamination techniques, no systematic review has ever occurred. The aim of this study was to perform a systematic review of the literature to determine the prevalence of infectious agents on shoe bottoms and possible decontamination strategies. Three electronic bibliographic databases were searched using a predefined search strategy evaluating prevalence of infectious pathogens on shoe bottoms and decontamination strategies. Quality assessment was performed independently by two reviews with disagreements resolved by consensus. Thirteen studies were identified that supported the hypothesis that shoe soles are a vector for infectious pathogens. Methicillin-resistant Staphylococcus aureus, Clostridium difficile and multidrug-resistant Gram-negative species among other pathogens were documented on shoe bottoms in the health care setting, in the community and among food workers. Fifteen studies were identified that investigated decontamination strategies for shoe soles. A number of decontamination strategies have been studied of which none have been shown to be consistently successful at disinfecting shoe soles. In conclusion, a high prevalence of microbiological pathogens was identified from shoe soles studied in the health care, community and animal worker setting. An effective decontamination strategy for shoe soles was not identified. Studies are needed to assess the potential for contaminated shoes to contribute to the transmission of infectious pathogens.

  20. Tick-borne pathogens and the vector potential of ticks in China.

    PubMed

    Yu, Zhijun; Wang, Hui; Wang, Tianhong; Sun, Wenying; Yang, Xiaolong; Liu, Jingze

    2015-01-14

    Ticks, as obligate blood-sucking ectoparasites, attack a broad range of vertebrates and transmit a great diversity of pathogenic microorganisms. They are considered second only to mosquitoes as vectors of human disease, and the most important vector of pathogens of domestic and wild animals. Of the 117 described species in the Chinese tick fauna, 60 are known to transmit one or more diseases: 36 species isolated within China and 24 species isolated outside China. Moreover, 38 of these species carry multiple pathogens, indicating the potentially vast role of these vectors in transmitting pathogens. Spotted fever is the most common tick-borne disease, and is carried by at least 27 tick species, with Lyme disease and human granulocytic anaplasmosis ranked as the second and third most widespread tick-borne diseases, carried by 13 and 10 species, respectively. Such knowledge provides us with clues for the identification of tick-associated pathogens and suggests ideas for the control of tick-borne diseases in China. However, the numbers of tick-associated pathogens and tick-borne diseases in China are probably underestimated because of the complex distribution and great diversity of tick species in this country.

  1. Potential Human Pathogenic Bacteria in a Mixed Urban Watershed as Revealed by Pyrosequencing

    PubMed Central

    Ibekwe, A. Mark; Leddy, Menu; Murinda, Shelton E.

    2013-01-01

    Current microbial source tracking (MST) methods for water depend on testing for fecal indicator bacterial counts or specific marker gene sequences to identify fecal contamination where potential human pathogenic bacteria could be present. In this study, we applied 454 high-throughput pyrosequencing to identify bacterial pathogen DNA sequences, including those not traditionally monitored by MST and correlated their abundances to specific sources of contamination such as urban runoff and agricultural runoff from concentrated animal feeding operations (CAFOs), recreation park area, waste-water treatment plants, and natural sites with little or no human activities. Samples for pyrosequencing were surface water, and sediment collected from 19 sites. A total of 12,959 16S rRNA gene sequences with average length of ≤400 bp were obtained, and were assigned to corresponding taxonomic ranks using ribosomal database project (RDP), Classifier and Greengenes databases. The percent of total potential pathogens were highest in urban runoff water (7.94%), agricultural runoff sediment (6.52%), and Prado Park sediment (6.00%), respectively. Although the numbers of DNA sequence tags from pyrosequencing were very high for the natural site, corresponding percent potential pathogens were very low (3.78–4.08%). Most of the potential pathogenic bacterial sequences identified were from three major phyla, namely, Proteobacteria, Bacteroidetes, and Firmicutes. The use of deep sequencing may provide improved and faster methods for the identification of pathogen sources in most watersheds so that better risk assessment methods may be developed to enhance public health. PMID:24278139

  2. Public health implications of Acanthamoeba and multiple potential opportunistic pathogens in roof-harvested rainwater tanks.

    PubMed

    Hamilton, K A; Ahmed, W; Palmer, A; Sidhu, J P S; Hodgers, L; Toze, S; Haas, C N

    2016-10-01

    A study of six potential opportunistic pathogens (Acanthamoeba spp., Legionella spp., Legionella longbeachae, Pseudomonas aeruginosa, Mycobacterium avium and Mycobacterium intracellulare) and an accidental human pathogen (Legionella pneumophila) in 134 roof-harvested rainwater (RHRW) tank samples was conducted using quantitative PCR (qPCR). All five opportunistic pathogens and accidental pathogen L. pneumophila were detected in rainwater tanks except Legionella longbeachae. Concentrations ranged up to 3.1×10(6) gene copies per L rainwater for Legionella spp., 9.6×10(5) gene copies per L for P. aeruginosa, 6.8×10(5) gene copies per L for M. intracellulare, 6.6×10(5) gene copies per L for Acanthamoeba spp., 1.1×10(5) gene copies per L for M. avium, and 9.8×10(3) gene copies per L for L. pneumophila. Among the organisms tested, Legionella spp. (99% tanks) were the most prevalent followed by M. intracellulare (78%). A survey of tank-owners provided data on rainwater end-uses. Fecal indicator bacteria (FIB) Escherichia coli and Enterococcus spp. were enumerated using culture-based methods, and assessed for correlations with opportunistic pathogens and L. pneumophila tested in this study. Opportunistic pathogens did not correlate well with FIB except E. coli vs. Legionella spp. (tau=0.151, P=0.009) and E. coli vs. M. intracellulare (tau=0.14, P=0.015). However, M. avium weakly correlated with both L. pneumophila (Kendall's tau=0.017, P=0.006) and M. intracellulare (tau=0.088, P=0.027), and Legionella spp. also weakly correlated with M. intracellulare (tau=0.128, P=0.028). The presence of these potential opportunistic pathogens in tank water may present health risks from both the potable and non-potable uses documented from the current survey data.

  3. Intranasal Immunization with an Archaeal Lipid Mucosal Vaccine Adjuvant and Delivery Formulation Protects against a Respiratory Pathogen Challenge

    PubMed Central

    Patel, Girishchandra B.; Zhou, Hongyan; Ponce, Amalia; Harris, Greg; Chen, Wangxue

    2010-01-01

    Archaeal lipid mucosal vaccine adjuvant and delivery (AMVAD) is a safe mucosal adjuvant that elicits long lasting and memory boostable mucosal and systemic immune responses to model antigens such as ovalbumin. In this study, we evaluated the potential of the AMVAD system for eliciting protective immunity against mucosal bacterial infections, using a mouse model of intranasal Francisella tularensis LVS (LVS) challenge. Intranasal immunization of mice with cell free extract of LVS (LVSCE) adjuvanted with the AMVAD system (LVSCE/AMVAD) induced F. tularensis-specific antibody responses in sera and bronchoalveolar lavage fluids, as well as antigen-specific splenocyte proliferation and IL-17 production. More importantly, the AMVAD vaccine partially protected the mice against a lethal intranasal challenge with LVS. Compared to LVSCE immunized and naïve mice, the LVSCE/AMVAD immunized mice showed substantial to significant reduction in pathogen burdens in the lungs and spleens, reduced serum and pulmonary levels of proinflammatory cytokines/chemokines, and longer mean time to death as well as significantly higher survival rates (p<0.05). These results suggest that the AMVAD system is a promising mucosal adjuvant and vaccine delivery technology, and should be explored further for its applications in combating mucosal infectious diseases. PMID:21206916

  4. Aspergillus sydowii and Other Potential Fungal Pathogens in Gorgonian Octocorals of the Ecuadorian Pacific.

    PubMed

    Soler-Hurtado, M Mar; Sandoval-Sierra, José Vladimir; Machordom, Annie; Diéguez-Uribeondo, Javier

    2016-01-01

    Emerging fungal diseases are threatening ecosystems and have increased in recent decades. In corals, the prevalence and consequences of these infections have also increased in frequency and severity. Coral reefs are affected by an emerging fungal disease named aspergillosis, caused by Aspergillus sydowii. This disease and its pathogen have been reported along the Caribbean and Pacific coasts of Colombia. Despite this, an important number of coral reefs worldwide have not been investigated for the presence of this pathogen. In this work, we carried out the surveillance of the main coral reef of the Ecuadorian Pacific with a focus on the two most abundant and cosmopolitan species of this ecosystem, Leptogorgia sp. and Leptogorgia obscura. We collected 59 isolates and obtained the corresponding sequences of the Internal Transcribed Spacers (ITS) of the ribosomal DNA. These were phylogenetically analyzed using MrBayes, which indicated the presence of two isolates of the coral reef pathogen A. sydowii, as well as 16 additional species that are potentially pathogenic to corals. Although the analyzed gorgonian specimens appeared healthy, the presence of these pathogens, especially of A. sydowii, alert us to the potential risk to the health and future survival of the Pacific Ecuadorian coral ecosystem under the current scenario of increasing threats and stressors to coral reefs, such as habitat alterations by humans and global climate change.

  5. Aspergillus sydowii and Other Potential Fungal Pathogens in Gorgonian Octocorals of the Ecuadorian Pacific

    PubMed Central

    Soler-Hurtado, M. Mar; Sandoval-Sierra, José Vladimir; Machordom, Annie; Diéguez-Uribeondo, Javier

    2016-01-01

    Emerging fungal diseases are threatening ecosystems and have increased in recent decades. In corals, the prevalence and consequences of these infections have also increased in frequency and severity. Coral reefs are affected by an emerging fungal disease named aspergillosis, caused by Aspergillus sydowii. This disease and its pathogen have been reported along the Caribbean and Pacific coasts of Colombia. Despite this, an important number of coral reefs worldwide have not been investigated for the presence of this pathogen. In this work, we carried out the surveillance of the main coral reef of the Ecuadorian Pacific with a focus on the two most abundant and cosmopolitan species of this ecosystem, Leptogorgia sp. and Leptogorgia obscura. We collected 59 isolates and obtained the corresponding sequences of the Internal Transcribed Spacers (ITS) of the ribosomal DNA. These were phylogenetically analyzed using MrBayes, which indicated the presence of two isolates of the coral reef pathogen A. sydowii, as well as 16 additional species that are potentially pathogenic to corals. Although the analyzed gorgonian specimens appeared healthy, the presence of these pathogens, especially of A. sydowii, alert us to the potential risk to the health and future survival of the Pacific Ecuadorian coral ecosystem under the current scenario of increasing threats and stressors to coral reefs, such as habitat alterations by humans and global climate change. PMID:27902710

  6. The potential for early and rapid pathogen detection within poultry processing through hyperspectral microscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The acquisition of hyperspectral microscopic images containing both spatial and spectral data has shown potential for the early and rapid optical classification of foodborne pathogens. A hyperspectral microscope with a metal halide light source and acousto-optical tunable filter (AOTF) collects 89 ...

  7. [ASSESSMENT OF POTENTIAL RISK FOR CONTAMINATION OF SURFACE WATER RESERVOIRS BY PATHOGENS OF HUMAN PARASITIC DISEASES].

    PubMed

    Khromenkova, E P; Dimidova, L L; Dumbadze, O S; Aidinov, G T; Shendo, G L; Agirov, A Kh; Batchaev, Kh Kh

    2015-01-01

    Sanitary and parasitological studies of the waste effluents and surface reservoir waters were conducted in the south of Russia. The efficiency of purification of waste effluents from the pathogens of parasitic diseases was investigated in the region's sewage-purification facilities. The water of the surface water reservoirs was found to contain helminthic eggs and larvae and intestinal protozoan cysts because of the poor purification and disinfection of service fecal sewage waters. The poor purification and disinvasion of waste effluents in the region determine the potential risk of contamination of the surface water reservoirs and infection of the population with the pathogens of human parasitic diseases.

  8. Antimicrobial susceptibility to levofloxacin and other antibacterial agents among common respiratory pathogens-a Brazilian perspective from the GLOBAL Surveillance Initiative 2001-2002.

    PubMed

    Mendes, C; Kiffer, C R V; Blosser-Middleton, R S; Jones, M E; Karlowsky, J A; Barth, A; Rossi, F; Andrade, S; Sader, H S; Thornsberry, C; Sahm, D F

    2004-06-01

    The GLOBAL (Global Landscape On Bactericidal Activity of Levofloxacin) Surveillance programme monitored antimicrobial susceptibility patterns of the key respiratory tract pathogens Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis collected in Brazil during 1997-1998, 1999-2000 and 2001-2002. Penicillin and azithromycin resistance among S. pneumoniae strains increased from 1997-1998, reaching 7.9% and 9.5%, respectively, in 2001-2002. Although decreasing by 4.9% since the previous study, trimethoprim-sulphamethoxazole resistance remained high at 33.7%. Concurrent resistance to penicillin, azithromycin and trimethoprim-sulphamethoxazole was seen in 2.9% of the S. pneumoniae isolates collected. Levofloxacin remained extremely active against S. pneumoniae, with 0.3% resistance reported in 1997-1998 and 0% resistance in 1999-2000 and 2001-2002. beta-Lactamase production in H. influenzae was > 10% in all three studies, with correspondingly high rates of ampicillin resistance. Trimethoprim-sulphamethoxazole was the least active agent tested against H. influenzae, with resistance rates of > 40% recorded in all three studies. All H. influenzae isolates were susceptible to cefuroxime, ceftriaxone, azithromycin and levofloxacin. Of the M. catarrhalis isolates, 98.0% in 1997-1998, 98.0% in 1999-2000 and 81.8% in 2001-2002 were beta-lactamase-positive. The continued high prevalence of antimicrobial resistance in Brazil underscores the importance of current surveillance initiatives. Levofloxacin, a fluoroquinolone prescribed widely for respiratory tract infections, continued to show potent activity against key respiratory pathogens.

  9. Nationwide surveillance of bacterial respiratory pathogens conducted by the surveillance committee of Japanese Society of Chemotherapy, the Japanese Association for Infectious Diseases, and the Japanese Society for Clinical Microbiology in 2010: General view of the pathogens' antibacterial susceptibility.

    PubMed

    Yanagihara, Katsunori; Kadota, Junichi; Aoki, Nobuki; Matsumoto, Tetsuya; Yoshida, Masaki; Yagisawa, Morimasa; Oguri, Toyoko; Sato, Junko; Ogasawara, Kazuhiko; Wakamura, Tomotaro; Sunakawa, Keisuke; Watanabe, Akira; Iwata, Satoshi; Kaku, Mitsuo; Hanaki, Hideaki; Ohsaki, Yoshinobu; Watari, Tomohisa; Toyoshima, Eri; Takeuchi, Kenichi; Shiokoshi, Mayumi; Takeda, Hiroaki; Miki, Makoto; Kumagai, Toshio; Nakanowatari, Susumu; Takahashi, Hiroshi; Utagawa, Mutsuko; Nishiya, Hajime; Kawakami, Sayoko; Kobayashi, Nobuyuki; Takasaki, Jin; Mezaki, Kazuhisa; Konosaki, Hisami; Aoki, Yasuko; Yamamoto, Yumiko; Shoji, Michi; Goto, Hajime; Saraya, Takeshi; Kurai, Daisuke; Okazaki, Mitsuhiro; Niki, Yoshihito; Yoshida, Koichiro; Kawana, Akihiko; Saionji, Katsu; Fujikura, Yuji; Miyazawa, Naoki; Kudo, Makoto; Sato, Yoshimi; Yamamoto, Masaki; Yoshida, Takashi; Nakamura, Masahiko; Tsukada, Hiroki; Imai, Yumiko; Tsukada, Ayami; Kawasaki, Satoshi; Honma, Yasuo; Yamamoto, Toshinobu; Ban, Nobuyoshi; Mikamo, Hiroshige; Sawamura, Haruki; Miyara, Takayuki; Toda, Hirofumi; Sato, Kaori; Nakamura, Tadahiro; Fujikawa, Yasunori; Mitsuno, Noriko; Mikasa, Keiichi; Kasahara, Kei; Sano, Reiko; Sugimoto, Keisuke; Asari, Seishi; Nishi, Isao; Toyokawa, Masahiro; Miyashita, Naoyuki; Koguchi, Yutaka; Kusano, Nobuchika; Mihara, Eiichirou; Kuwabara, Masao; Watanabe, Yaeko; Kawasaki, Yuji; Takeda, Kenichi; Tokuyasu, Hirokazu; Masui, Kayoko; Negayama, Kiyoshi; Hiramatsu, Kazufumi; Aoki, Yosuke; Fukuoka, Mami; Magarifuchi, Hiroki; Nagasawa, Zenzo; Suga, Moritaka; Muranaka, Hiroyuki; Morinaga, Yoshitomo; Honda, Junichi; Fujita, Masaki

    2015-06-01

    The nationwide surveillance on antimicrobial susceptibility of bacterial respiratory pathogens from patients in Japan, was conducted by Japanese Society of Chemotherapy, Japanese Association for Infectious Diseases and Japanese Society for Clinical Microbiology in 2010. The isolates were collected from clinical specimens obtained from well-diagnosed adult patients with respiratory tract infections during the period from January and April 2010 by three societies. Antimicrobial susceptibility testing was conducted at the central reference laboratory according to the method recommended by Clinical and Laboratory Standard Institutes using maximum 45 antibacterial agents. Susceptibility testing was evaluable with 954 strains (206 Staphylococcus aureus, 189 Streptococcus pneumoniae, 4 Streptococcus pyogenes, 182 Haemophilus influenzae, 74 Moraxella catarrhalis, 139 Klebsiella pneumoniae and 160 Pseudomonas aeruginosa). Ratio of methicillin-resistant S. aureus was as high as 50.5%, and those of penicillin-intermediate and -resistant S. pneumoniae were 1.1% and 0.0%, respectively. Among H. influenzae, 17.6% of them were found to be β-lactamase-non-producing ampicillin (ABPC)-intermediately resistant, 33.5% to be β-lactamase-non-producing ABPC-resistant and 11.0% to be β-lactamase-producing ABPC-resistant strains. Extended spectrum β-lactamase-producing K. pneumoniae and multi-drug resistant P. aeruginosa with metallo β-lactamase were 2.9% and 0.6%, respectively. Continuous national surveillance of antimicrobial susceptibility of respiratory pathogens is crucial in order to monitor changing patterns of susceptibility and to be able to update treatment recommendations on a regular basis.

  10. Monitoring of antimicrobial susceptibility of respiratory tract pathogens isolated from diseased cattle and pigs across Europe, 2009-2012: VetPath results.

    PubMed

    El Garch, Farid; de Jong, Anno; Simjee, Shabbir; Moyaert, Hilde; Klein, Ulrich; Ludwig, Carolin; Marion, Hervé; Haag-Diergarten, Silke; Richard-Mazet, Alexandra; Thomas, Valérie; Siegwart, Ed

    2016-10-15

    VetPath is an ongoing pan-European antibiotic susceptibility monitoring programme that collects pathogens from diseased cattle, pigs and poultry. In the current study, 996 isolates from cattle and pig respiratory tract infections were tested for their antimicrobial susceptibilities. Non-replicate lung samples or nasopharyngeal/nasal swabs were collected from animals with acute clinical signs in 10 countries during 2009-2012. Pasteurella multocida, Mannheimia haemolytica and Histophilus somni from cattle and P. multocida, Actinobacillus pleuropneumoniae, Haemophilus parasuis, Bordetella bronchiseptica and Streptococcus suis from pigs were isolated by standard methods. S. suis was also isolated from meningitis cases. MIC values of 16 or 17 antibiotics were assessed centrally by broth microdilution following CLSI standards. Results were interpreted using CLSI breakpoints where available. Cattle isolates were generally highly susceptible to most antibiotics, except to tetracycline (3.0-12.0% resistance). Low levels of resistance (0-4.0%) were observed for the macrolide antibiotics. Resistance to spectinomycin varied from 0 to 6.0%. In pig isolates similar observations were made. Resistance to amoxicillin/clavulanic acid, ceftiofur, enrofloxacin, florfenicol, tulathromycin, tiamulin and tilmicosin was absent or <2%. Trimethoprim/sulfamethoxazole resistance varied from 1.9 to 5.3%, but tetracycline resistance varied from 20.4% in P. multocida to 88.1% in S. suis. For most antibiotics and pathogens the percentage resistance remained unchanged or only increased numerically as compared to that of the period 2002-2006. In conclusion, absence or low resistance to antibiotics with defined clinical breakpoints, except for tetracycline, was observed among the major respiratory tract pathogens recovered from livestock. Comparison of all antibiotics and organisms was hampered since for almost half of the antibiotics no CLSI-defined breakpoints were available.

  11. Mycoherbicidal Potential of Phaeoacremonium italicum, A New Pathogen of Eichhornia crassipes Infesting Harike Wetland, India

    PubMed Central

    Singh, Birinderjit; Meshram, Vineet; Kumar, Maneek

    2016-01-01

    Mycoherbicides are exclusive biotechnology products which offer a non-chemical solution to control noxious weeds on the land as well as aquatic in systems, viz a viz saving environment from hazardous impact of synthetic chemicals. The present paper highlights the mycobiota associated with Eichhornia crassipes infesting Harike wetland area of Punjab and evaluation of their pathogenic potential for futuristic application as a mycoherbicide. Of the 20 isolates tested by leaf detached assay and whole plant bioassays, only one isolate (#8 BJSSL) caused 100% damage to E. crassipes. Further, the culture filtrate of this isolate also exhibited a similar damage to the leaves in an in vitro detached leaf assay. The potential isolate was identified as Phaeoacremonium italicum using classical and modern molecular methods. This is the first report of P. italicum as a pathogen of E. crassipes and of its potential use as a biological control agent for the management of water hyacinth. PMID:27433118

  12. Mycoherbicidal Potential of Phaeoacremonium italicum, A New Pathogen of Eichhornia crassipes Infesting Harike Wetland, India.

    PubMed

    Singh, Birinderjit; Saxena, Sanjai; Meshram, Vineet; Kumar, Maneek

    2016-06-01

    Mycoherbicides are exclusive biotechnology products which offer a non-chemical solution to control noxious weeds on the land as well as aquatic in systems, viz a viz saving environment from hazardous impact of synthetic chemicals. The present paper highlights the mycobiota associated with Eichhornia crassipes infesting Harike wetland area of Punjab and evaluation of their pathogenic potential for futuristic application as a mycoherbicide. Of the 20 isolates tested by leaf detached assay and whole plant bioassays, only one isolate (#8 BJSSL) caused 100% damage to E. crassipes. Further, the culture filtrate of this isolate also exhibited a similar damage to the leaves in an in vitro detached leaf assay. The potential isolate was identified as Phaeoacremonium italicum using classical and modern molecular methods. This is the first report of P. italicum as a pathogen of E. crassipes and of its potential use as a biological control agent for the management of water hyacinth.

  13. Bacteria associated with crabs from cold waters with emphasis on the occurrence of potential human pathogens.

    PubMed Central

    Faghri, M A; Pennington, C L; Cronholm, L S; Atlas, R M

    1984-01-01

    A diverse array of bacterial species, including several potential human pathogens, was isolated from edible crabs collected in cold waters. Crabs collected near Kodiak Island, Alaska, contained higher levels of bacteria than crabs collected away from regions of human habitation. The bacteria associated with the crabs collected near Kodiak included Yersinia enterocolitica, Klebsiella pneumoniae, and coagulase-negative Staphylococcus species; the pathogenicity of these isolates was demonstrated in mice. Although coliforms were not found, the bacterial species associated with the tissues of crabs collected near Kodiak indicate possible fecal contamination that may have occurred through contact with sewage. Compared with surrounding waters and sediments, the crab tissues contained much higher proportions of gram-positive cocci. As revealed by indirect plate counts and direct scanning electron microscopic observations, muscle and hemolymph tissues contained much lower levels of bacteria than shell and gill tissues. After the death of a crab, however, the numbers of bacteria associated with hemolymph and muscle tissues increased significantly. Microcosm studies showed that certain bacterial populations, e.g., Vibrio cholerae, can be bioaccumulated in crab gill tissues. The results of this study indicate the need for careful review of waste disposal practices where edible crabs may be contaminated with microorganisms that are potential human pathogens and the need for surveillance of shellfish for pathogenic microorganisms that naturally occur in marine ecosystems. Images PMID:6742824

  14. Probiotic Potential of Lactobacillus Strains with Antimicrobial Activity against Some Human Pathogenic Strains

    PubMed Central

    Shokryazdan, Parisa; Sieo, Chin Chin; Kalavathy, Ramasamy; Liang, Juan Boo; Alitheen, Noorjahan Banu; Faseleh Jahromi, Mohammad; Ho, Yin Wan

    2014-01-01

    The objective of this study was to isolate, identify, and characterize some lactic acid bacterial strains from human milk, infant feces, and fermented grapes and dates, as potential probiotics with antimicrobial activity against some human pathogenic strains. One hundred and forty bacterial strains were isolated and, after initial identification and a preliminary screening for acid and bile tolerance, nine of the best isolates were selected and further identified using 16 S rRNA gene sequences. The nine selected isolates were then characterized in vitro for their probiotic characteristics and their antimicrobial activities against some human pathogens. Results showed that all nine isolates belonged to the genus Lactobacillus. They were able to tolerate pH 3 for 3 h, 0.3% bile salts for 4 h, and 1.9 mg/mL pancreatic enzymes for 3 h. They exhibited good ability to attach to intestinal epithelial cells and were not resistant to the tested antibiotics. They also showed good antimicrobial activities against the tested pathogenic strains of humans, and most of them exhibited stronger antimicrobial activity than the reference strain L. casei Shirota. Thus, the nine Lactobacillus strains could be considered as potential antimicrobial probiotic strains against human pathogens and should be further studied for their human health benefits. PMID:25105147

  15. Experimental demonstration of pathogenic potential of Anisakis physeteris and Anisakis paggiae in Wistar rats.

    PubMed

    Romero, María Carmen; Valero, Adela; Navarro, María Concepción; Hierro, Ignacio; Barón, Sergio David; Martín-Sánchez, Joaquina

    2014-12-01

    Anisakis morphotype I is the principal etiologic agent of human anisakiasis, with differences in pathogenicity found between the Anisakis simplex s.s. and A. pegreffii species; however, the role of morphotype II larvae in this illness is not well understood. The purpose of this study is to verify the ability of morphotype II larvae to invade tissues via the experimental infection of Wistar rats, an animal model which simulates infection in humans. In the in vivo assay, 7.1% (4/56 L3 morphotype II) showed pathogenic potential, defined as the capacity of the larvae to cause lesions, attach to the gastrointestinal wall or penetrate it. Two of these larvae, one of A. physeteris and one of A. paggiae, penetrated the stomach wall and were found within the abdominal cavity, with the first one producing a small lesion with blood vessel breakage. The majority of the L3 larvae of morphotype II were found in the intestine (51.8%; 29/56) with the caecum being the least frequent location (8.9%; 5/56). In contrast, 44.0% (11/25) of the morphotype I larvae demonstrated pathogenic potential. Isoenzyme electrophoresis, PCR-RFLP of ITS1-5.8 s-ITS2 and PCR-sequencing of the cox2 mitochondrial gene were used to identify these larvae as A. physeteris (42.9%), A. paggiae (30.3%) and A. brevispiculata (1.8%). Although the morphotype II larvae of A. physeteris and A. paggiae have lower pathogenic potential than morphotype I larvae of A. simplex s.s. (93 and 91% lower, respectively), they may still be implicated in human anisakiasis, as they are capable of attaching to and penetrating the gastrointestinal wall of animals, demonstrating a similar pathogenicity to that of A. pegreffii. The techniques used for the identification of species reveal a great genetic heterogeneity of A. paggiae and A. physeteris, suggesting the existence of sibling species.

  16. Snow in the city as a spore bank of potentially pathogenic fungi.

    PubMed

    Ejdys, Elżbieta; Biedunkiewicz, Anna; Dynowska, Maria; Sucharzewska, Ewa

    2014-02-01

    This study evaluates the role of snow as a specific ecological niche and a vector in fungal spreading with particular emphasis on potential pathogens in seasonally and daily changing conditions. The experimental material was fungi isolated from the atmospheric air, snow cover, and fragments of ice and soil from underneath the snow cover. The total count of microfungi in the air before snowfall, i.e. in the autumn, reached 1756.1 CFU/m(3) on average. After the first snowfalls, it dropped to 85.2 CFU/m(3). The analyzed samples of snow cover contained from 101.6 to 8500.0 CFU/m(3) of fungi. Furthermore, 26 species of yeast and yeast-like fungi were isolated from the experimental material. Amongst the analyzed species, 13 were potential anthropopathogens. Though another three species were isolated from organ ontocenoses, i.e. Candida intermedia, Saccharomyces bayanus and Zygosaccharomyces rouxii, their pathogenic potential has not yet been explicitly confirmed. The results of the presented study may be applied in predicting concentrations of fungal spores responsible for mycoses. The first snowfalls significantly reduced the number of colony-forming units of fungi in the air. Under conditions of temperate climate, snow becomes a temporary bank of yeast-like fungi spores and while it melts cells of deposited microfungi migrate to the atmosphere. Hence, individuals with impaired immunity or in the course of immunosuppression or recovery should avoid long walks during periods of snow melting. The count of fungi in urban bioaerosol during the melt may be reduced through systematic removal of snow cover, which is a significant reservoir of potential pathogens. In addition, it should be noted that even a typical psychrophilic strain, capable of surviving at a temperature of 37°C, may bear a significant pathogenic potential.

  17. Contamination of community water sources by potentially pathogenic vibrios following sea water inundation.

    PubMed

    Kanungo, Reba; Shashikala; Karunasagar, I; Srinivasan, S; Sheela, Devi; Venkatesh, K; Anitha, P

    2007-12-01

    Potentially pathogenic members of the Vibrionaceae family including Vibrio cholerae and Vibrio parahemolyticus were isolated from domestic sources of drinking water in coastal villages following sea water inundation during the tsunami in Southern India. Phenotypic and genotypic studies were done to confirm the identity and detection of toxins. Vibrio-gyr (gyrase B gene) was detected in all sixteen vibrio isolates. Toxin regulating genes i.e.: ctx gene, tdh gene, and trh gene, however were not detected in any of the strains, thereby ruling out presence of toxins which could endanger human life. Other potentially pathogenic bacteria Aeromonas and Plesiomonas were also isolated from hand pumps and wells, in a few localities. There was no immediate danger in the form of an outbreak or sporadic gastroenteritis at the time of the study. Timely chlorination and restoration of potable water supply to the flood affected population by governmental and nongovernmental agencies averted waterborne gastroenteritis. Assessment of quality of water and detection of potential virulent organisms is an important public health activity following natural disasters. This work highlights the importance of screening water sources for potentially pathogenic microorganisms after natural disasters to avert outbreaks of gastroenteritis and other infectious diseases.

  18. Respiratory Displacement of the Thoracic Aorta: Physiological Phenomenon With Potential Implications for Thoracic Endovascular Repair

    SciTech Connect

    Weber, Tim Frederik; Tetzlaff, Ralf; Rengier, Fabian; Geisbuesch, Philipp; Kopp-Schneider, Annette; Boeckler, Dittmar; Eichinger, Monika; Kauczor, Hans-Ulrich; Tengg-Kobligk, Hendrik von

    2009-07-15

    The purpose of this study was to assess the magnitude and direction of respiratory displacement of the ascending and descending thoracic aorta during breathing maneuvers. In 11 healthy nonsmokers, dynamic magnetic resonance imaging was performed in transverse orientation at the tracheal bifurcation during maximum expiration and inspiration as well as tidal breathing. The magnitude and direction of aortic displacement was determined relatively to resting respiratory position for the ascending (AA) and descending (DA) aorta. To estimate a respiratory threshold for occurrence of distinct respiratory aortic motion, the latter was related to the underlying change in anterior-posterior thorax diameter. Compound displacement between maximum expiration and inspiration was 24.3 {+-} 6.0 mm for the AA in the left anterior direction and 18.2 {+-} 5.5 mm for the DA in the right anterior direction. The mean respiratory thorax excursion during tidal breathing was 8.9 {+-} 2.8 mm. The respiratory threshold, i.e., the increase in thorax diameter necessary to result in respiratory aortic displacement, was estimated to be 15.7 mm. The data suggest that after a threshold of respiratory thorax excursion is exceeded, respiration is accompanied by significant displacement of the thoracic aorta. Although this threshold may not be reached during tidal breathing in the majority of individuals, segmental differences during forced respiration impact on aortic geometry, may result in additional extrinsic forces on the aortic wall, and may be of significance for aortic prostheses designed for thoracic endovascular aortic repair.

  19. Impact of milk fish farming in the tropics on potentially pathogenic vibrios.

    PubMed

    Reichardt, W T; Reyes, J M; Pueblos, M J; Lluisma, A O

    2013-12-15

    Ratios of sucrose-negative to sucrose-positive vibrios on TCBS agar (suc-/suc+) indicate the abundance of potential human pathogenic non-cholera vibrios in coastal mariculture environments of the Lingayen Gulf (Philippines. In guts of adult maricultured milkfish (Chanos chanos) of suc- vibrios reached extreme peak values ranging between 2 and 545 million per g wet weight. Suc- vibrios outnumbered suc+ vibrios in anoxic sediments, too, and were rarely predominant in coastal waters or in oxidized sediments. Suc-/suc+ ratios in sediments increased toward the mariculture areas with distance from the open sea at decreasing redox potentials. There is circumstantial evidence that suc- vibrios can be dispersed from mariculture areas to adjacent environments including coral reefs. An immediate human health risk by pathogenic Vibrio species is discounted, since milkfish guts contained mainly members of the Enterovibrio group. A representative isolate of these contained proteolytic and other virulence factors, but no genes encoding toxins characteristic of clinical Vibrio species.

  20. A preliminary study on the potential of Mycoplasma pneumoniae to induce dyskaryotic change in respiratory epithelium in adult community-acquired pneumonia

    PubMed Central

    An, Shu-Chang; Yang, Dong-Hong; Luo, Chao-Feng; Chen, Xin; Liu, Guo-Tian; Weng, Yan; Liu, Jing-Zhe; Shang, Ying; Wang, Rui-Qin; Gao, Zhan-Cheng

    2016-01-01

    Background: This study aimed to explore the cellular morphology of respiratory epithelium in Mycoplasma pneumonia (MpP) patients. Materials and Methods: The cast-off cell morphological findings from bronchoscopic brushings in MpP and community-acquired pneumonia (CAP) caused by typical pathogens were reviewed. Results: Compared with the CAP group, cellular dysplasia in respiratory tract epithelial brushings was significantly greater in MpP patients (P = 0.033). Conclusion: Unique biological characteristics and mechanisms of pathogenesis of Mycoplasma pneumoniae (Mp) may result in dyskaryotic changes in respiratory epithelium in adult MpP. PMID:28163727

  1. Emerging highly pathogenic H5 avian influenza viruses in France during winter 2015/16: phylogenetic analyses and markers for zoonotic potential

    PubMed Central

    Briand, François-Xavier; Schmitz, Audrey; Ogor, Katell; Le Prioux, Aurélie; Guillou-Cloarec, Cécile; Guillemoto, Carole; Allée, Chantal; Le Bras, Marie-Odile; Hirchaud, Edouard; Quenault, Hélène; Touzain, Fabrice; Cherbonnel-Pansart, Martine; Lemaitre, Evelyne; Courtillon, Céline; Gares, Hélène; Daniel, Patrick; Fediaevsky, Alexandre; Massin, Pascale; Blanchard, Yannick; Eterradossi, Nicolas; van der Werf, Sylvie; Jestin, Véronique; Niqueux, Eric

    2017-01-01

    Several new highly pathogenic (HP) H5 avian influenza virus (AIV) have been detected in poultry farms from south-western France since November 2015, among which an HP H5N1. The zoonotic potential and origin of these AIVs immediately became matters of concern. One virus of each subtype H5N1 (150169a), H5N2 (150233) and H5N9 (150236) was characterised. All proved highly pathogenic for poultry as demonstrated molecularly by the presence of a polybasic cleavage site in their HA protein – with a sequence (HQRRKR/GLF) previously unknown among avian H5 HPAI viruses – or experimentally by the in vivo demonstration of an intravenous pathogenicity index of 2.9 for the H5N1 HP isolate. Phylogenetic analyses based on the full genomes obtained by NGS confirmed that the eight viral segments of the three isolates were all part of avian Eurasian phylogenetic lineage but differed from the Gs/Gd/1/96-like lineage. The study of the genetic characteristics at specific amino acid positions relevant for modulating the adaptation to and the virulence for mammals showed that presently, these viruses possess most molecular features characteristic of AIV and lack some major characteristics required for efficient respiratory transmission to or between humans. The three isolates are therefore predicted to have no significant pandemic potential. PMID:28277218

  2. Genotyping of potentially pathogenic Acanthamoeba strains isolated from nasal swabs of healthy individuals in Peru.

    PubMed

    Cabello-Vílchez, Alfonso Martín; Martín-Navarro, Carmen María; López-Arencibia, Atteneri; Reyes-Batlle, María; González, Ana C; Guerra, Humberto; Gotuzzo, Eduardo; Valladares, Basilio; Piñero, José E; Lorenzo-Morales, Jacob

    2014-02-01

    Free Living Amoebae (FLA) of Acanthamoeba genus are widely distributed in the environment and can be found in the air, soil and water; and have also been isolated from air-conditioning units. In humans, they are causative agents of a sight-threating infection of the cornea, Acanthamoeba keratitis (AK) and a fatal infection of the central nervous system known as Granulomatous Amoebic Encephalitis (GAE). In this study, a survey was conducted in order to determine the presence and pathogenic potential of free-living amoebae of Acanthamoeba genus in nasal swabs from individuals in two regions of Peru. Identification of isolates was based on cyst morphology and PCR-sequencing of the Diagnostic Fragment 3 to identify strains at the genotype level. The pathogenic potential of the isolates was also assayed using temperature and osmotolerance assays and extracellular proteases zymograms. The obtained results revealed that all isolated strains exhibited pathogenic potential. After sequencing the highly variable DF3 (Diagnostic Fragment 3) region in the 18S rRNA gene as previously described, genotype T4 was found to be the most common one in the samples included in this study but also genotype T15 was identified. To the best of our knowledge, this is the first study on the characterization of Acanthamoeba strains at the genotype level and the first report of genotype T4 and T15 in Peru.

  3. Bioactive Potential of Actinomycetes from Less Explored Ecosystems against Mycobacterium tuberculosis and Other Nonmycobacterial Pathogens

    PubMed Central

    Venugopal, Gopikrishnan; Subramaniam, Balaji; Ramasamy, Balagurunathan

    2014-01-01

    Bioactive potential of actinomycetes isolated from certain less explored Indian ecosystems against Mycobacterium tuberculosis and other nonmycobacterial pathogens was investigated. Actinomycetes were isolated from the soil samples collected from desert, coffee plantation, rubber forest, and hill area and their cultural and micromorphological characteristics were studied. Crude extracts were prepared by agar surface fermentation and tested against M. tuberculosis isolates by luciferase reporter phage (LRP) assay at 100 µg/mL. Activity against nonmycobacterial pathogens was studied by agar plug method. Totally 54 purified cultures of actinomycetes including 43 Streptomyces and 11 non-Streptomyces were isolated. While screening for antitubercular activity, extracts of 39 actinomycetes showed activity against one or more M. tuberculosis isolates whereas 27 isolates exhibited antagonistic activity against nonmycobacterial pathogens. In particular crude extracts from sixteen actinomycete isolates inhibited all the three M. tuberculosis isolates tested. Findings of the present study concluded that less explored ecosystems investigated in this study are the potential resource for bioactive actinomycetes. Further purification and characterization of active molecule from the potential extracts will pave the way for determination of MIC, toxicity, and specificity studies. PMID:27437460

  4. Improved Detection of Respiratory Pathogens by Use of High-Quality Sputum with TaqMan Array Card Technology.

    PubMed

    Wolff, Bernard J; Bramley, Anna M; Thurman, Kathleen A; Whitney, Cynthia G; Whitaker, Brett; Self, Wesley H; Arnold, Sandra R; Trabue, Christopher; Wunderink, Richard G; McCullers, Jon; Edwards, Kathryn M; Jain, Seema; Winchell, Jonas M

    2017-01-01

    New diagnostic platforms often use nasopharyngeal or oropharyngeal (NP/OP) swabs for pathogen detection for patients hospitalized with community-acquired pneumonia (CAP). We applied multipathogen testing to high-quality sputum specimens to determine if more pathogens can be identified relative to NP/OP swabs. Children (<18 years old) and adults hospitalized with CAP were enrolled over 2.5 years through the Etiology of Pneumonia in the Community (EPIC) study. NP/OP specimens with matching high-quality sputum (defined as ≤10 epithelial cells/low-power field [lpf] and ≥25 white blood cells/lpf or a quality score [q-score] definition of 2+) were tested by TaqMan array card (TAC), a multipathogen real-time PCR detection platform. Among 236 patients with matched specimens, a higher proportion of sputum specimens had ≥1 pathogen detected compared with NP/OP specimens in children (93% versus 68%; P < 0.0001) and adults (88% versus 61%; P < 0.0001); for each pathogen targeted, crossing threshold (CT) values were earlier in sputum. Both bacterial (361 versus 294) and viral detections (245 versus 140) were more common in sputum versus NP/OP specimens, respectively, in both children and adults. When available, high-quality sputum may be useful for testing in hospitalized CAP patients.

  5. Expression of cytotoxicity by potential pathogens in the standard Escherichia coli collection of reference (ECOR) strains.

    PubMed

    Lai, X H; Wang, S Y; Uhlin, B E

    1999-11-01

    The standard Escherichia coli collection of reference (ECOR) strains was examined for ability to exert cytotoxicity towards mammalian cells. A group of strains with functional haemolysin expression caused strong cytotoxicity and detachment in J774 macrophage cells as measured by lactate dehydrogenase release and as observed under a microscope. The expression of haemolysin was monitored by using antisera recognizing the E. coli alpha-haemolysin, the HlyA protein, and by quantitative haemolysis assays. The presence of the hlyA gene, which may be part of a pathogenicity island, was also confirmed. These analyses revealed that different ECOR strains express quantitatively different levels of haemolysin. One putative enteroaggregative E. coli (EAEC) strain was also found in the ECOR collection. The EAEC strain was characterized by the clump formation assay, PCR amplification of the EAEC DNA probe sequence and confirmative sequence analysis of the amplified fragment. The EAEC heat-stable enterotoxin 1 gene, astA, was found in 14% (10/72) of the ECOR strains and a consensus sequence for astA was proposed by comparing these sequences with those from pathogens. The astA gene appeared to be plasmid-located. Based on evidence from the work of other laboratories and from the present findings, it is concluded that the ECOR collection contains strains that may represent pathogenic E. coli. It is noted that caution is necessary when handling or disposing of those potentially pathogenic ECOR strains.

  6. Local adaptation and evolutionary potential along a temperature gradient in the fungal pathogen Rhynchosporium commune

    PubMed Central

    Stefansson, Tryggvi S; McDonald, Bruce A; Willi, Yvonne

    2013-01-01

    To predict the response of plant pathogens to climate warming, data are needed on current thermal adaptation, the pathogen's evolutionary potential, and the link between them. We conducted a common garden experiment using isolates of the fungal pathogen Rhynchosporium commune from nine barley populations representing climatically diverse locations. Clonal replicates of 126 genetically distinct isolates were assessed for their growth rate at 12°C, 18°C, and 22°C. Populations originating from climates with higher monthly temperature variation had higher growth rate at all three temperatures compared with populations from climates with less temperature fluctuation. Population differentiation in growth rate (QST) was significantly higher at 22°C than population differentiation for neutral microsatellite loci (GST), consistent with local adaptation for growth at higher temperatures. At 18°C, we found evidence for stabilizing selection for growth rate as QST was significantly lower than GST. Heritability of growth rate under the three temperatures was substantial in all populations (0.58–0.76). Genetic variation was lower in populations with higher growth rate at the three temperatures and evolvability increased under heat stress in seven of nine populations. Our findings imply that the distribution of this pathogen is unlikely to be genetically limited under climate warming, due to its high genetic variation and plasticity for thermal tolerance. PMID:23745143

  7. Medfly Ceratitis capitata as Potential Vector for Fire Blight Pathogen Erwinia amylovora: Survival and Transmission.

    PubMed

    Ordax, Mónica; Piquer-Salcedo, Jaime E; Santander, Ricardo D; Sabater-Muñoz, Beatriz; Biosca, Elena G; López, María M; Marco-Noales, Ester

    2015-01-01

    Monitoring the ability of bacterial plant pathogens to survive in insects is required for elucidating unknown aspects of their epidemiology and for designing appropriate control strategies. Erwinia amylovora is a plant pathogenic bacterium that causes fire blight, a devastating disease in apple and pear commercial orchards. Studies on fire blight spread by insects have mainly focused on pollinating agents, such as honeybees. However, the Mediterranean fruit fly (medfly) Ceratitis capitata (Diptera: Tephritidae), one of the most damaging fruit pests worldwide, is also common in pome fruit orchards. The main objective of the study was to investigate whether E. amylovora can survive and be transmitted by the medfly. Our experimental results show: i) E. amylovora can survive for at least 8 days inside the digestive tract of the medfly and until 28 days on its external surface, and ii) medflies are able to transmit the bacteria from inoculated apples to both detached shoots and pear plants, being the pathogen recovered from lesions in both cases. This is the first report on E. amylovora internalization and survival in/on C. capitata, as well as the experimental transmission of the fire blight pathogen by this insect. Our results suggest that medfly can act as a potential vector for E. amylovora, and expand our knowledge on the possible role of these and other insects in its life cycle.

  8. Potentially Treatable Disorder Diagnosed Post Mortem by Exome Analysis in a Boy with Respiratory Distress

    PubMed Central

    Imperatore, Valentina; Mencarelli, Maria Antonietta; Fallerini, Chiara; Bianciardi, Laura; Ariani, Francesca; Furini, Simone; Renieri, Alessandra; Mari, Francesca; Frullanti, Elisa

    2016-01-01

    We highlight the importance of exome sequencing in solving a clinical case of a child who died at 14 months after a series of respiratory crises. He was the half-brother of a girl diagnosed at 7 years with the early-onset seizure variant of Rett syndrome due to CDKL5 mutation. We performed a test for CDKL5 in the boy, which came back negative. Driven by the mother’s compelling need for a diagnosis, we moved forward performing whole exome sequencing analysis. Surprisingly, two missense mutations in compound heterozygosity were identified in the RAPSN gene encoding a receptor-associated protein with a key role in clustering and anchoring nicotinic acetylcholine receptors at synaptic sites. This gene is responsible for a congenital form of myasthenic syndrome, a disease potentially treatable with cholinesterase inhibitors. Therefore, an earlier diagnosis in this boy would have led to a better clinical management and prognosis. Our study supports the key role of exome sequencing in achieving a definite diagnosis in severe perinatal diseases, an essential step especially when a specific therapy is available. PMID:26927095

  9. Rapid detection of highly pathogenic porcine reproductive and respiratory syndrome virus by a fluorescent probe-based isothermal recombinase polymerase amplification assay.

    PubMed

    Yang, Yang; Qin, Xiaodong; Sun, Yingjun; Chen, Ting; Zhang, Zhidong

    2016-12-01

    A novel fluorescent probe-based real-time reverse transcription recombinase polymerase amplification (real-time RT-RPA) assay was developed for rapid detection of highly pathogenic type 2 porcine reproductive and respiratory syndrome virus (HP-PRRSV). The sensitivity analysis showed that the detection limit of RPA was 70 copies of HP-PRRSV RNA/reaction. The real-time RT-RPA highly specific amplified HP-PRRSV with no cross-reaction with classic PRRSV, classic swine fever virus, pseudorabies virus, and foot-and-mouth disease virus. Assessment with 125 clinical samples showed that the developed real-time RT-RPA assay was well correlated with real-time RT-qPCR assays for detection of HP-PRRSV. These results suggest that the developed real-time RT-RPA assay is suitable for rapid detection of HP-PRRSV.

  10. Genome Sequencing and Comparative Genomics Analysis Revealed Pathogenic Potential in Penicillium capsulatum as a Novel Fungal Pathogen Belonging to Eurotiales

    PubMed Central

    Yang, Ying; Chen, Min; Li, Zongwei; Al-Hatmi, Abdullah M. S.; de Hoog, Sybren; Pan, Weihua; Ye, Qiang; Bo, Xiaochen; Li, Zhen; Wang, Shengqi; Wang, Junzhi; Chen, Huipeng; Liao, Wanqing

    2016-01-01

    Penicillium capsulatum is a rare Penicillium species used in paper manufacturing, but recently it has been reported to cause invasive infection. To research the pathogenicity of the clinical Penicillium strain, we sequenced the genomes and transcriptomes of the clinical and environmental strains of P. capsulatum. Comparative analyses of these two P. capsulatum strains and close related strains belonging to Eurotiales were performed. The assembled genome sizes of P. capsulatum are approximately 34.4 Mbp in length and encode 11,080 predicted genes. The different isolates of P. capsulatum are highly similar, with the exception of several unique genes, INDELs or SNPs in the genes coding for glycosyl hydrolases, amino acid transporters and circumsporozoite protein. A phylogenomic analysis was performed based on the whole genome data of 38 strains belonging to Eurotiales. By comparing the whole genome sequences and the virulence-related genes from 20 important related species, including fungal pathogens and non-human pathogens belonging to Eurotiales, we found meaningful pathogenicity characteristics between P. capsulatum and its closely related species. Our research indicated that P. capsulatum may be a neglected opportunistic pathogen. This study is beneficial for mycologists, geneticists and epidemiologists to achieve a deeper understanding of the genetic basis of the role of P. capsulatum as a newly reported fungal pathogen. PMID:27761131

  11. Biofilm formation and cellulose expression by Bordetella avium 197N, the causative agent of bordetellosis in birds and an opportunistic respiratory pathogen in humans.

    PubMed

    McLaughlin, Kimberley; Folorunso, Ayorinde O; Deeni, Yusuf Y; Foster, Dona; Gorbatiuk, Oksana; Hapca, Simona M; Immoor, Corinna; Koza, Anna; Mohammed, Ibrahim U; Moshynets, Olena; Rogalsky, Sergii; Zawadzki, Kamil; Spiers, Andrew J

    2017-01-26

    Although bacterial cellulose synthase (bcs) operons are widespread within the Proteobacteria phylum, subunits required for the partial-acetylation of the polymer appear to be restricted to a few γ-group soil, plant-associated and phytopathogenic pseudomonads, including Pseudomonas fluorescens SBW25 and several Pseudomonas syringae pathovars. However, a bcs operon with acetylation subunits has also been annotated in the unrelated β-group respiratory pathogen, Bordetella avium 197N. Our comparison of subunit protein sequences and GC content analyses confirms the close similarity between the B. avium 197N and pseudomonad operons and suggests that, in both cases, the cellulose synthase and acetylation subunits were acquired as a single unit. Using static liquid microcosms, we can confirm that B. avium 197N expresses low levels of cellulose in air-liquid interface biofilms and that biofilm strength and attachment levels could be increased by elevating c-di-GMP levels like the pseudomonads, but cellulose was not required for biofilm formation itself. The finding that B. avium 197N is capable of producing cellulose from a highly-conserved, but relatively uncommon bcs operon raises the question of what functional role this modified polymer plays during the infection of the upper respiratory tract or survival between hosts, and what environmental signals control its production.

  12. The potential role and limitations of echocardiography in acute respiratory distress syndrome.

    PubMed

    Lazzeri, Chiara; Cianchi, Giovanni; Bonizzoli, Manuela; Batacchi, Stefano; Peris, Adriano; Gensini, Gian Franco

    2016-04-01

    Bedside use of Doppler echocardiography is being featured as a promising, clinically useful tool in assessing the pulmonary circulation in patients with acute respiratory distress syndrome (ARDS). The present review is aimed at summarizing the available evidence obtained with echocardiography on right ventricle (RV) function and pulmonary circulation in ARDS and to highlight the potential of this technique in clinical practice (only articles in English language were considered). According to the available evidence on echocardiographic findings, the following conclusions can be drawn: (a) echocardiography (transthoracic and transesophageal) has a growing role in the management ARDS patients mainly because of the strict interactions between the lung (and ventilation) and the RV and pulmonary circulation; (b) there may be a continuum of alterations in RV size and function and pulmonary circulation which may end in the development of acute cor pulmonale, probably paralleling ARDS disease severity; and (c) the detection of acute cor pulmonale should prompt intensivists to tailor their ventilatory strategy to the individual patient depending on the echocardiography findings. Bearing in mind the clinical role and growing importance of echocardiography in ARDS and the available evidence on this topic, we present a flow chart including the parameters to be measured and the timing of echo exams in ARDS patients. Despite the important progress that echocardiography has gained in the evaluation of patients with ARDS, several open questions remain and echocardiography still appears to be underused in these patients. A more systematic use of echocardiography (mainly through shared protocols) in ARDS could help intensivists to tailor the optimal treatment in individual patients as well as highlighting the limits and potential of this methodology in patients with ALI.

  13. Mitochondrial genome acquisition restores respiratory function and tumorigenic potential of cancer cells without mitochondrial DNA.

    PubMed

    Tan, An S; Baty, James W; Dong, Lan-Feng; Bezawork-Geleta, Ayenachew; Endaya, Berwini; Goodwin, Jacob; Bajzikova, Martina; Kovarova, Jaromira; Peterka, Martin; Yan, Bing; Pesdar, Elham Alizadeh; Sobol, Margarita; Filimonenko, Anatolyj; Stuart, Shani; Vondrusova, Magdalena; Kluckova, Katarina; Sachaphibulkij, Karishma; Rohlena, Jakub; Hozak, Pavel; Truksa, Jaroslav; Eccles, David; Haupt, Larisa M; Griffiths, Lyn R; Neuzil, Jiri; Berridge, Michael V

    2015-01-06

    We report that tumor cells without mitochondrial DNA (mtDNA) show delayed tumor growth, and that tumor formation is associated with acquisition of mtDNA from host cells. This leads to partial recovery of mitochondrial function in cells derived from primary tumors grown from cells without mtDNA and a shorter lag in tumor growth. Cell lines from circulating tumor cells showed further recovery of mitochondrial respiration and an intermediate lag to tumor growth, while cells from lung metastases exhibited full restoration of respiratory function and no lag in tumor growth. Stepwise assembly of mitochondrial respiratory (super)complexes was correlated with acquisition of respiratory function. Our findings indicate horizontal transfer of mtDNA from host cells in the tumor microenvironment to tumor cells with compromised respiratory function to re-establish respiration and tumor-initiating efficacy. These results suggest pathophysiological processes for overcoming mtDNA damage and support the notion of high plasticity of malignant cells.

  14. Virulence Attributes and Host Response Assays for Determining Pathogenic Potential of Pseudomonas Strains Used in Biotechnology.

    PubMed

    Tayabali, Azam F; Coleman, Gordon; Nguyen, Kathy C

    2015-01-01

    Pseudomonas species are opportunistically pathogenic to humans, yet closely related species are used in biotechnology applications. In order to screen for the pathogenic potential of strains considered for biotechnology applications, several Pseudomonas strains (P.aeruginosa (Pa), P.fluorescens (Pf), P.putida (Pp), P.stutzeri (Ps)) were compared using functional virulence and toxicity assays. Most Pa strains and Ps grew at temperatures between 28°C and 42°C. However, Pf and Pp strains were the most antibiotic resistant, with ciprofloxacin and colistin being the most effective of those tested. No strain was haemolytic on sheep blood agar. Almost all Pa, but not other test strains, produced a pyocyanin-like chromophore, and caused cytotoxicity towards cultured human HT29 cells. Murine endotracheal exposures indicated that the laboratory reference strain, PAO1, was most persistent in the lungs. Only Pa strains induced pro-inflammatory and inflammatory responses, as measured by elevated cytokines and pulmonary Gr-1 -positive cells. Serum amyloid A was elevated at ≥ 48 h post-exposure by only some Pa strains. No relationship was observed between strains and levels of peripheral leukocytes. The species designation or isolation source may not accurately reflect pathogenic potential, since the clinical strain Pa10752 was relatively nonvirulent, but the industrial strain Pa31480 showed comparable virulence to PAO1. Functional assays involving microbial growth, cytotoxicity and murine immunological responses may be most useful for identifying problematic Pseudomonas strains being considered for biotechnology applications.

  15. Virulence Attributes and Host Response Assays for Determining Pathogenic Potential of Pseudomonas Strains Used in Biotechnology

    PubMed Central

    Tayabali, Azam F.; Coleman, Gordon; Nguyen, Kathy C.

    2015-01-01

    Pseudomonas species are opportunistically pathogenic to humans, yet closely related species are used in biotechnology applications. In order to screen for the pathogenic potential of strains considered for biotechnology applications, several Pseudomonas strains (P.aeruginosa (Pa), P.fluorescens (Pf), P.putida (Pp), P.stutzeri (Ps)) were compared using functional virulence and toxicity assays. Most Pa strains and Ps grew at temperatures between 28°C and 42°C. However, Pf and Pp strains were the most antibiotic resistant, with ciprofloxacin and colistin being the most effective of those tested. No strain was haemolytic on sheep blood agar. Almost all Pa, but not other test strains, produced a pyocyanin-like chromophore, and caused cytotoxicity towards cultured human HT29 cells. Murine endotracheal exposures indicated that the laboratory reference strain, PAO1, was most persistent in the lungs. Only Pa strains induced pro-inflammatory and inflammatory responses, as measured by elevated cytokines and pulmonary Gr-1 -positive cells. Serum amyloid A was elevated at ≥ 48 h post-exposure by only some Pa strains. No relationship was observed between strains and levels of peripheral leukocytes. The species designation or isolation source may not accurately reflect pathogenic potential, since the clinical strain Pa10752 was relatively nonvirulent, but the industrial strain Pa31480 showed comparable virulence to PAO1. Functional assays involving microbial growth, cytotoxicity and murine immunological responses may be most useful for identifying problematic Pseudomonas strains being considered for biotechnology applications. PMID:26619347

  16. Electroanalytical biosensors and their potential for food pathogen and toxin detection.

    PubMed

    Palchetti, Ilaria; Mascini, Marco

    2008-05-01

    The detection and identification of foodborne pathogens continue to rely on conventional culturing techniques. These are very elaborate, time-consuming, and have to be completed in a microbiology laboratory and are therefore not suitable for on-site monitoring. The need for a more rapid, reliable, specific, and sensitive method of detecting a target analyte, at low cost, is the focus of a great deal of research. Biosensor technology has the potential to speed up the detection, increase specificity and sensitivity, enable high-throughput analysis, and to be used for monitoring of critical control points in food production. This article reviews food pathogen detection methods based on electrochemical biosensors, specifically amperometric, potentiometric, and impedimetric biosensors. The underlying principles and application of these biosensors are discussed with special emphasis on new biorecognition elements, nanomaterials, and lab on a chip technology.

  17. The effect of glyphosate on potential pathogens and beneficial members of poultry microbiota in vitro.

    PubMed

    Shehata, Awad A; Schrödl, Wieland; Aldin, Alaa A; Hafez, Hafez M; Krüger, Monika

    2013-04-01

    The use of glyphosate modifies the environment which stresses the living microorganisms. The aim of the present study was to determine the real impact of glyphosate on potential pathogens and beneficial members of poultry microbiota in vitro. The presented results evidence that the highly pathogenic bacteria as Salmonella Entritidis, Salmonella Gallinarum, Salmonella Typhimurium, Clostridium perfringens and Clostridium botulinum are highly resistant to glyphosate. However, most of beneficial bacteria as Enterococcus faecalis, Enterococcus faecium, Bacillus badius, Bifidobacterium adolescentis and Lactobacillus spp. were found to be moderate to highly susceptible. Also Campylobacter spp. were found to be susceptible to glyphosate. A reduction of beneficial bacteria in the gastrointestinal tract microbiota by ingestion of glyphosate could disturb the normal gut bacterial community. Also, the toxicity of glyphosate to the most prevalent Enterococcus spp. could be a significant predisposing factor that is associated with the increase in C. botulinum-mediated diseases by suppressing the antagonistic effect of these bacteria on clostridia.

  18. Comparative Genomic Analysis Reveals a Possible Novel Non-Tuberculous Mycobacterium Species with High Pathogenic Potential

    PubMed Central

    Choo, Siew Woh; Dutta, Avirup; Wong, Guat Jah; Wee, Wei Yee; Ang, Mia Yang; Siow, Cheuk Chuen

    2016-01-01

    Mycobacteria have been reported to cause a wide range of human diseases. We present the first whole-genome study of a Non-Tuberculous Mycobacterium, Mycobacterium sp. UM_CSW (referred to hereafter as UM_CSW), isolated from a patient diagnosed with bronchiectasis. Our data suggest that this clinical isolate is likely a novel mycobacterial species, supported by clear evidence from molecular phylogenetic, comparative genomic, ANI and AAI analyses. UM_CSW is closely related to the Mycobacterium avium complex. While it has characteristic features of an environmental bacterium, it also shows a high pathogenic potential with the presence of a wide variety of putative genes related to bacterial virulence and shares very similar pathogenomic profiles with the known pathogenic mycobacterial species. Thus, we conclude that this possible novel Mycobacterium species should be tightly monitored for its possible causative role in human infections. PMID:27035710

  19. Making vaccines "on demand": a potential solution for emerging pathogens and biodefense?

    PubMed

    De Groot, Anne S; Einck, Leo; Moise, Leonard; Chambers, Michael; Ballantyne, John; Malone, Robert W; Ardito, Matthew; Martin, William

    2013-09-01

    The integrated US Public Health Emergency Medical Countermeasures Enterprise (PHEMCE) has made great strides in strategic preparedness and response capabilities. There have been numerous advances in planning, biothreat countermeasure development, licensure, manufacturing, stockpiling and deployment. Increased biodefense surveillance capability has dramatically improved, while new tools and increased awareness have fostered rapid identification of new potential public health pathogens. Unfortunately, structural delays in vaccine design, development, manufacture, clinical testing and licensure processes remain significant obstacles to an effective national biodefense rapid response capability. This is particularly true for the very real threat of "novel pathogens" such as the avian-origin influenzas H7N9 and H5N1, and new coronaviruses such as hCoV-EMC. Conventional approaches to vaccine development, production, clinical testing and licensure are incompatible with the prompt deployment needed for an effective public health response. An alternative approach, proposed here, is to apply computational vaccine design tools and rapid production technologies that now make it possible to engineer vaccines for novel emerging pathogen and WMD biowarfare agent countermeasures in record time. These new tools have the potential to significantly reduce the time needed to design string-of-epitope vaccines for previously unknown pathogens. The design process-from genome to gene sequence, ready to insert in a DNA plasmid-can now be accomplished in less than 24 h. While these vaccines are by no means "standard," the need for innovation in the vaccine design and production process is great. Should such vaccines be developed, their 60-d start-to-finish timeline would represent a 2-fold faster response than the current standard.

  20. Multiple Pathogens Including Potential New Species in Tick Vectors in Côte d’Ivoire

    PubMed Central

    Ehounoud, Cyrille Bilé; Yao, Kouassi Patrick; Dahmani, Mustapha; Achi, Yaba Louise; Amanzougaghene, Nadia; Kacou N’Douba, Adèle; N’Guessan, Jean David; Raoult, Didier; Fenollar, Florence; Mediannikov, Oleg

    2016-01-01

    Background Our study aimed to assess the presence of different pathogens in ticks collected in two regions in Côte d’Ivoire. Methodology/Principal Findings Real-time PCR and standard PCR assays coupled to sequencing were used. Three hundred and seventy eight (378) ticks (170 Amblyomma variegatum, 161 Rhipicepalus microplus, 3 Rhipicephalus senegalensis, 27 Hyalomma truncatum, 16 Hyalomma marginatum rufipes, and 1 Hyalomma impressum) were identified and analyzed. We identified as pathogenic bacteria, Rickettsia africae in Am. variegatum (90%), Rh. microplus (10%) and Hyalomma spp. (9%), Rickettsia aeschlimannii in Hyalomma spp. (23%), Rickettsia massiliae in Rh. senegalensis (33%) as well as Coxiella burnetii in 0.2%, Borrelia sp. in 0.2%, Anaplasma centrale in 0.2%, Anaplasma marginale in 0.5%, and Ehrlichia ruminantium in 0.5% of all ticks. Potential new species of Borrelia, Anaplasma, and Wolbachia were detected. Candidatus Borrelia africana and Candidatus Borrelia ivorensis (detected in three ticks) are phylogenetically distant from both the relapsing fever group and Lyme disease group borreliae; both were detected in Am. variegatum. Four new genotypes of bacteria from the Anaplasmataceae family were identified, namely Candidatus Anaplasma ivorensis (detected in three ticks), Candidatus Ehrlichia urmitei (in nine ticks), Candidatus Ehrlichia rustica (in four ticks), and Candidatus Wolbachia ivorensis (in one tick). Conclusions/Significance For the first time, we demonstrate the presence of different pathogens such as R. aeschlimannii, C. burnetii, Borrelia sp., A. centrale, A. marginale, and E. ruminantium in ticks in Côte d’Ivoire as well as potential new species of unknown pathogenicity. PMID:26771308

  1. Absence of mucosal immunity in the human upper respiratory tract to the commensal bacteria Neisseria lactamica but not pathogenic Neisseria meningitidis during the peak age of nasopharyngeal carriage.

    PubMed

    Vaughan, Andrew T; Gorringe, Andrew; Davenport, Victoria; Williams, Neil A; Heyderman, Robert S

    2009-02-15

    The normal flora that colonizes the mucosal epithelia has evolved diverse strategies to evade, modulate, or suppress the immune system and avoid clearance. Neisseria lactamica and Neisseria meningitidis are closely related obligate inhabitants of the human upper respiratory tract. N. lactamica is a commensal but N. meningitidis is an opportunistic pathogen that occasionally causes invasive disease such as meningitis and septicemia. We demonstrate that unlike N. meningitidis, N. lactamica does not prime the development of mucosal T or B cell memory during the peak period of colonization. This cannot be explained by the induction of peripheral tolerance or regulatory CD4(+)CD25(+) T cell activity. Instead, N. lactamica mediates a B cell-dependent mitogenic proliferative response that is absent to N. meningitidis. This mitogenic response is associated with the production of T cell-independent polyclonal IgM that we propose functions by shielding colonizing N. lactamica from the adaptive immune system, maintaining immunological ignorance in the host. We conclude that, in contrast to N. meningitidis, N. lactamica maintains a commensal relationship with the host in the absence of an adaptive immune response. This may prolong the period of susceptibility to colonization by both pathogenic and nonpathogenic Neisseria species.

  2. Effect of porcine circovirus type 2a or 2b on infection kinetics and pathogenicity of two genetically divergent strains of porcine reproductive and respiratory syndrome virus in the conventional pig model

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to characterize the infection dynamics and pathogenicity of two heterologous type 2 porcine reproductive and respiratory syndrome virus (PRRSV) isolates in a conventional pig model under the influence of concurrent porcine circovirus (PCV) subtype 2a or 2b infection. ...

  3. Iron Availability Increases the Pathogenic Potential of Salmonella Typhimurium and Other Enteric Pathogens at the Intestinal Epithelial Interface

    PubMed Central

    Kortman, Guus A. M.; Boleij, Annemarie; Swinkels, Dorine W.; Tjalsma, Harold

    2012-01-01

    Recent trials have questioned the safety of untargeted oral iron supplementation in developing regions. Excess of luminal iron could select for enteric pathogens at the expense of beneficial commensals in the human gut microflora, thereby increasing the incidence of infectious diseases. The objective of the current study was to determine the effect of high iron availability on virulence traits of prevalent enteric pathogens at the host-microbe interface. A panel of enteric bacteria was cultured under iron-limiting conditions and in the presence of increasing concentrations of ferric citrate to assess the effect on bacterial growth, epithelial adhesion, invasion, translocation and epithelial damage in vitro. Translocation and epithelial integrity experiments were performed using a transwell system in which Caco-2 cells were allowed to differentiate to a tight epithelial monolayer mimicking the intestinal epithelial barrier. Growth of Salmonella typhimurium and other enteric pathogens was increased in response to iron. Adhesion of S. typhimurium to epithelial cells markedly increased when these bacteria were pre-incubated with increasing iron concentration (P = 0.0001), whereas this was not the case for the non-pathogenic Lactobacillus plantarum (P = 0.42). Cellular invasion and epithelial translocation of S. typhimurium followed the trend of increased adhesion. Epithelial damage was increased upon incubation with S. typhimurium or Citrobacter freundii that were pre-incubated under iron-rich conditions. In conclusion, our data fit with the consensus that oral iron supplementation is not without risk as iron could, in addition to inducing pathogenic overgrowth, also increase the virulence of prevalent enteric pathogens. PMID:22272265

  4. Surveillance for emerging respiratory viruses.

    PubMed

    Al-Tawfiq, Jaffar A; Zumla, Alimuddin; Gautret, Philippe; Gray, Gregory C; Hui, David S; Al-Rabeeah, Abdullah A; Memish, Ziad A

    2014-10-01

    Several new viral respiratory tract infectious diseases with epidemic potential that threaten global health security have emerged in the past 15 years. In 2003, WHO issued a worldwide alert for an unknown emerging illness, later named severe acute respiratory syndrome (SARS). The disease caused by a novel coronavirus (SARS-CoV) rapidly spread worldwide, causing more than 8000 cases and 800 deaths in more than 30 countries with a substantial economic impact. Since then, we have witnessed the emergence of several other viral respiratory pathogens including influenza viruses (avian influenza H5N1, H7N9, and H10N8; variant influenza A H3N2 virus), human adenovirus-14, and Middle East respiratory syndrome coronavirus (MERS-CoV). In response, various surveillance systems have been developed to monitor the emergence of respiratory-tract infections. These include systems based on identification of syndromes, web-based systems, systems that gather health data from health facilities (such as emergency departments and family doctors), and systems that rely on self-reporting by patients. More effective national, regional, and international surveillance systems are required to enable rapid identification of emerging respiratory epidemics, diseases with epidemic potential, their specific microbial cause, origin, mode of acquisition, and transmission dynamics.

  5. Bacillus amyloliquefaciens G1: A Potential Antagonistic Bacterium against Eel-Pathogenic Aeromonas hydrophila

    PubMed Central

    Cao, Haipeng; He, Shan; Wei, Ruopeng; Diong, Marek; Lu, Liqun

    2011-01-01

    Recent studies have revealed that the use of probiotics is an alternative to control marine aeromonas. However, few probiotics are available against Aeromonas hydrophila infections in eels. In the present study, a potential antagonistic strain G1 against the eel-pathogenic A. hydrophila was isolated from sediment underlying brackish water. Its extracellular products with antibacterial activities were shown to be stable under wide range of pH, temperature, and proteinase K. It was initially identified as Bacillus amyloliquefaciens using API identification kits and confirmed to be B. amyloliquefaciens strain (GenBank accession number DQ422953) by phylogenetic analysis. In addition, it was shown to be safe for mammalians, had a wide anti-A. hydrophila spectrum, and exhibited significant effects on inhibiting the growth of the eel-pathogenic A. hydrophila both in vitro and in vivo. To the best of our knowledge, this is the first report on a promising antagonistic Bacillus amyloliquefaciens strain from brackish water sediment against eel-pathogenic A. hydrophila. PMID:21754944

  6. Synanthropic Mammals as Potential Hosts of Tick-Borne Pathogens in Panama.

    PubMed

    Bermúdez, Sergio E; Gottdenker, Nicole; Krishnvajhala, Aparna; Fox, Amy; Wilder, Hannah K; González, Kadir; Smith, Diorene; López, Marielena; Perea, Milixa; Rigg, Chystrie; Montilla, Santiago; Calzada, José E; Saldaña, Azael; Caballero, Carlos M; Lopez, Job E

    2017-01-01

    Synanthropic wild mammals can be important hosts for many vector-borne zoonotic pathogens. The aim of this study was determine the exposure of synanthropic mammals to two types of tick-borne pathogens in Panama, spotted fever group Rickettsia (SFGR) and Borrelia relapsing fever (RF) spirochetes. One hundred and thirty-one wild mammals were evaluated, including two gray foxes, two crab-eating foxes (from zoos), four coyotes, 62 opossum and 63 spiny rats captured close to rural towns. To evaluate exposure to SFGR, serum samples from the animals were tested by indirect immunofluorescence assay (IFA) using Rickettsia rickettsii and Candidatus Rickettsia amblyommii antigen. Immunoblotting was performed using Borrelia turicatae protein lysates and rGlpQ, to assess infection caused by RF spirochetes. One coyote (25%) and 27 (43%) opossums showed seroreactivity to SFGR. Of these opossums, 11 were seroreactive to C. R. amblyommii. Serological reactivity was not detected to B. turicatae in mammal samples. These findings may reflect a potential role of both mammals in the ecology of tick-borne pathogens in Panama.

  7. Synanthropic Mammals as Potential Hosts of Tick-Borne Pathogens in Panama

    PubMed Central

    Bermúdez, Sergio E.; Gottdenker, Nicole; Krishnvajhala, Aparna; Fox, Amy; Wilder, Hannah K.; González, Kadir; Smith, Diorene; López, Marielena; Perea, Milixa; Rigg, Chystrie; Montilla, Santiago; Calzada, José E.; Saldaña, Azael; Caballero, Carlos M.

    2017-01-01

    Synanthropic wild mammals can be important hosts for many vector-borne zoonotic pathogens. The aim of this study was determine the exposure of synanthropic mammals to two types of tick-borne pathogens in Panama, spotted fever group Rickettsia (SFGR) and Borrelia relapsing fever (RF) spirochetes. One hundred and thirty-one wild mammals were evaluated, including two gray foxes, two crab-eating foxes (from zoos), four coyotes, 62 opossum and 63 spiny rats captured close to rural towns. To evaluate exposure to SFGR, serum samples from the animals were tested by indirect immunofluorescence assay (IFA) using Rickettsia rickettsii and Candidatus Rickettsia amblyommii antigen. Immunoblotting was performed using Borrelia turicatae protein lysates and rGlpQ, to assess infection caused by RF spirochetes. One coyote (25%) and 27 (43%) opossums showed seroreactivity to SFGR. Of these opossums, 11 were seroreactive to C. R. amblyommii. Serological reactivity was not detected to B. turicatae in mammal samples. These findings may reflect a potential role of both mammals in the ecology of tick-borne pathogens in Panama. PMID:28060928

  8. Elucidation of bacteria found in car interiors and strategies to reduce the presence of potential pathogens.

    PubMed

    Stephenson, Rachel E; Gutierrez, Daniel; Peters, Cindy; Nichols, Mark; Boles, Blaise R

    2014-01-01

    The human microbiome is influenced by a number of factors, including environmental exposure to microbes. Because many humans spend a large amount of time in built environments, it can be expected that the microbial ecology of these environments will influence the human microbiome. In an attempt to further understand the microbial ecology of built environments, the microbiota of car interiors was analyzed using culture dependent and culture independent methods. While it was found that the number and type of bacteria varied widely among the cars and sites tested, Staphylococcus and Propionibacterium were nearly always the dominant genera found at the locations sampled. Because Staphylococcus is of particular concern to human health, the characteristics of this genus found in car interiors were investigated. Staphylococcus epidermidis, S. aureus, and S. warnerii were the most prevalent staphylococcal species found, and 22.6% of S. aureus strains isolated from shared community vehicles were resistant to methicillin. The reduction in the prevalence of pathogenic bacteria in cars by using silver-based antimicrobial surface coatings was also evaluated. Coatings containing 5% silver ion additives were applied to steering wheels, placed in cars for five months and were found to eliminate the presence of culturable pathogenic bacteria recovered from these sites relative to controls. Together, these results provide new insight into the microbiota found in an important built environment, the automobile, and potential strategies for controlling the presence of human pathogens.

  9. Intestinal bacterial overgrowth includes potential pathogens in the carbohydrate overload models of equine acute laminitis.

    PubMed

    Onishi, Janet C; Park, Joong-Wook; Prado, Julio; Eades, Susan C; Mirza, Mustajab H; Fugaro, Michael N; Häggblom, Max M; Reinemeyer, Craig R

    2012-10-12

    Carbohydrate overload models of equine acute laminitis are used to study the development of lameness. It is hypothesized that a diet-induced shift in cecal bacterial communities contributes to the development of the pro-inflammatory state that progresses to laminar failure. It is proposed that vasoactive amines, protease activators and endotoxin, all bacterial derived bioactive metabolites, play a role in disease development. Questions regarding the oral bioavailability of many of the bacterial derived bioactive metabolites remain. This study evaluates the possibility that a carbohydrate-induced overgrowth of potentially pathogenic cecal bacteria occurs and that bacterial translocation contributes toward the development of the pro-inflammatory state. Two groups of mixed-breed horses were used, those with laminitis induced by cornstarch (n=6) or oligofructan (n=6) and non-laminitic controls (n=8). Cecal fluid and tissue homogenates of extra-intestinal sites including the laminae were used to enumerate Gram-negative and -positive bacteria. Horses that developed Obel grade2 lameness, revealed a significant overgrowth of potentially pathogenic Gram-positive and Gram-negative intestinal bacteria within the cecal fluid. Although colonization of extra-intestinal sites with potentially pathogenic bacteria was not detected, results of this study indicate that cecal/colonic lymphadenopathy and eosinophilia develop in horses progressing to lameness. It is hypothesized that the pro-inflammatory state in carbohydrate overload models of equine acute laminitis is driven by an immune response to the rapid overgrowth of Gram-positive and Gram-negative cecal bacterial communities in the gut. Further equine research is indicated to study the immunological response, involving the lymphatic system that develops in the model.

  10. Potential effects of mixed infections in ticks on transmission dynamics of pathogens: comparative analysis of published records

    USGS Publications Warehouse

    Ginsberg, Howard S.

    2008-01-01

    Ticks are often infected with more than one pathogen, and several field surveys have documented nonrandom levels of coinfection. Levels of coinfection by pathogens in four tick species were analyzed using published infection data. Coinfection patterns of pathogens in field-collected ticks include numerous cases of higher or lower levels of coinfection than would be expected due to chance alone, but the vast majority of these cases can be explained on the basis of vertebrate host associations of the pathogens, without invoking interactions between pathogens within ticks. Nevertheless, some studies have demonstrated antagonistic interactions, and some have suggested potential mutualisms, between pathogens in ticks. Negative or positive interactions between pathogens within ticks can affect pathogen prevalence, and thus transmission patterns. Probabilistic projections suggest that the effect on transmission depends on initial conditions. When the number of tick bites is relatively low (e.g., for ticks biting humans) changes in prevalence in ticks are predicted to have a commensurate effects on pathogen transmission. In contrast, when the number of tick bites is high (e.g., for wild animal hosts) changes in pathogen prevalence in ticks have relatively little effect on levels of transmission to reservoir hosts, and thus on natural transmission cycles.

  11. Jerusalem artichokes stimulate growth of broiler chickens and protect them against endotoxins and potential cecal pathogens.

    PubMed

    Kleessen, Brigitta; Elsayed, N A A E; Loehren, U; Schroedl, W; Krueger, Monika

    2003-11-01

    Control of intestinal pathogens during the earliest phases of broiler production may be the best strategy for the reduction of human pathogens on processed broiler carcasses. The recent ban on antibiotics in poultry feed has served to focus much attention on alternative methods of controlling the gastrointestinal microflora. A field trial was conducted to evaluate the effect of the fructan-rich Jerusalem artichoke, or topinambur (administered as 0.5% topinambur syrup in drinking water), on cultural numbers of selected cecal bacteria (total aerobes, Enterobacteriaceae, Bdellovibrio spp., and Clostridium perfringens) and levels of bacterial endotoxins as well as on body weights and relative weights of organs (the pancreas and the bursa of Fabricius) of chickens in the first 35 days of life (with weekly investigations being conducted). One-day-old broiler chickens (Ross 308) were randomly assigned to experimental (with topinambur) and control (without topinambur) groups. They were allowed free access to a standard broiler diet without growth-promoting antibiotics. Topinambur treatment resulted in a significant increase (P < 0.01) in cecal counts of B. bacteriovorus, which parasitizes susceptible gram-negative pathogens. Topinambur led to significantly smaller numbers of total aerobes, Enterobacteriaceae, and C. perfringens as well as to reduced levels of endotoxins in the blood compared with those for control birds. Increased body weights resulting from topinambur consumption were observed on day 35 of the trial period (P < 0.05). The relative weights of the pancreas and the bursa of Fabricius, however, were higher (P < 0.05) for topinambur-treated broilers than for control birds at the ages of 14, 21, 28, and 35 days. These results indicate that a small amount of topinambur in broilers' drinking water has a beneficial effect on growth performance, reduces bacterial endotoxin levels, and suppresses potential pathogens in broilers' ceca.

  12. [Relationship between growth potential of pine, population density of Monochamus alternatus and pathogenicity of Bursaphlenchus xyloophilus].

    PubMed

    Ding, Y; Lü, C; Han, B; Pou, H; Wu, M

    2001-06-01

    The results showed that the growth potential of pine (x) is negative related to the population density of Monochamus alternatus (y) and the pathoyenecity of Bursaphlenchus xyloophilus (z). But the population density of Monochamus alternatus is positively related to the pathogenicity of Bursaphlenchus xyloophilus. Three linear equations regression line were established as y = 1793.771 - 16404.47x, z = 31.80989 - 241.9274x, y = -407.611 + 70.51478z. Correlation coefficient is -0.8139, -0.8770 and +0.9864 respectively.

  13. Bacteriology of the Upper Respiratory Tract: What is Important?

    PubMed Central

    Cimolai, Nevio

    1988-01-01

    Oropharyngeal and nasopharyngeal swabs are commonly collected from patients with a variety of respiratory infections. Unfortunately, the significance of potential pathogens in such specimens is clouded by the prevalence of these organisms in asymptomatic patients and in patients with non-bacterial upper respiratory tract illnesses. Specimens from the oro-and nasopharynx seldom predict the flora in other parts of the respiratory tract, and empiric antibiotic therapy for infections such as acute otitis media, sinusitis, and pneumonia is usually inevitable. The author of this article reviews the bacteriology of the upper respiratory tract and makes recommendations for diagnosis and treatment. PMID:21253244

  14. Recombinant respiratory syncytial virus lacking secreted glycoprotein G is attenuated, non-pathogenic but induces protective immunity.

    PubMed

    Maher, Caroline F; Hussell, Tracy; Blair, Edward; Ring, Christopher J A; Openshaw, Peter J M

    2004-10-01

    Respiratory syncytial virus (RSV) causes intense pulmonary inflammatory responses in some infected infants. The surface attachment protein 'G' of RSV has membrane-bound and secreted forms and shows homology to the CX3C chemokine fractalkine. Using recombinant techniques, we generated replication-competent recombinant clonal RSV expressing normal G proteins ('rRSV') or only the membrane-bound form of G ('Gmem rRSV'). Both recombinants grew well in HEp-2 cells, but after primary intranasal infection in mice, pulmonary Gmem rRSV replication was reduced tenfold compared to parental or rRSV; moreover, CCL2 and CCL5 production was greatly reduced and no apparent disease or pulmonary cellular infiltration was observed. However, Gmem rRSV-infected mice developed good antibody responses and were fully protected against subsequent intranasal challenge with parental virus. Even in mice sensitized to G by cutaneous infection with recombinant vaccinia expressing G, intranasal challenge with Gmem rRSV caused insignificant disease. We conclude that secreted G is a key viral product assisting virus replication in vivo, enhancing CCL2 and CCL5 production and promoting illness. Engineered RSV mutants lacking the ability to secrete G are thus promising vaccine candidates.

  15. Aerobic bacterial oral flora of garter snakes: development of normal flora and pathogenic potential for snakes and humans.

    PubMed

    Goldstein, E J; Agyare, E O; Vagvolgyi, A E; Halpern, M

    1981-05-01

    Garter snakes that are used for scientific laboratory studies or kept as exotic pets often become ill and die early in captivity. They may also act as reservoirs of potential human pathogens or transmit infection to man. A total of 126 strains of aerobic and facultative bacteria, most potential human and snake pathogens, were isolated from 82 garter snake oropharyngeal cultures. Coagulase-negative Staphylococcus species were the most common species isolated. Acinetobacter calcoaceticus var. anitratus, Hafnia alvei, Arizona hinshawii, Salmonella species, Shigella species, Klebsiella oxytoca, and Pseudomonas aeruginosa were among the potential pathogens isolated. The spectrum of bacteria with potential for causing oral and pulmonary infections in garter snakes is greater than has been previously appreciated. Garter snakes should also be considered reservoirs of human pathogens, and appropriate precautions should be taken by laboratory personnel and pet owners.

  16. Fluorescence in situ hybridization investigation of potentially pathogenic bacteria involved in neonatal porcine diarrhea

    PubMed Central

    2014-01-01

    Background Neonatal diarrhea is a multifactorial condition commonly present on pig farms and leads to economic losses due to increased morbidity and mortality of piglets. Immature immune system and lack of fully established microbiota at birth predispose neonatal piglets to infection with enteric pathogens. The microorganisms that for decades have been associated with enteritis and diarrhea in suckling piglets are: rotavirus A, coronavirus, enterotoxigenic Escherichia coli (ETEC), Clostridium perfringens type C, Cryptosporidium spp., Giardia spp., Cystoisospora suis and Strongyloides ransomi. However, in recent years, the pig industry has experienced an increased number of neonatal diarrhea cases in which the above mentioned pathogens are no longer detected. Potentially pathogenic bacteria have recently received focus in the research on the possible etiology of neonatal diarrhea not caused by common pathogens. The primary aim of this study was to investigate the role of E. coli, Enterococcus spp., C. perfringens and C. difficile in the pathogenesis of neonatal porcine diarrhea with no established casual agents. Fluorescence in situ hybridization with oligonucleotide probes was applied on the fixed intestinal tissue samples from 51 diarrheic and 50 non-diarrheic piglets collected from four Danish farms during outbreaks of neonatal diarrhea not caused by well-known enteric pathogens. Furthermore, an association between the presence of these bacteria and histological lesions was evaluated. Results The prevalence of fluorescence signals specific for E. coli, C. perfringens and C. difficile was similar in both groups of piglets. However, Enterococcus spp. was primarily detected in the diarrheic piglets. Furthermore, adherent bacteria were detected in 37 % diarrheic and 14 % non-diarrheic piglets. These bacteria were identified as E. coli and Enterococcus spp. and their presence in the intestinal mucosa was associated with histopathological changes. Conclusions The

  17. Unravelling Linkages between Plant Community Composition and the Pathogen-Suppressive Potential of Soils

    PubMed Central

    Latz, Ellen; Eisenhauer, Nico; Rall, Björn Christian; Scheu, Stefan; Jousset, Alexandre

    2016-01-01

    Plant diseases cause dramatic yield losses worldwide. Current disease control practices can be deleterious for the environment and human health, calling for alternative and sustainable management regimes. Soils harbour microorganisms that can efficiently suppress pathogens. Uncovering mediators driving their functioning in the field still remains challenging, but represents an essential step in order to develop strategies for increased soil health. We set up plant communities of varying richness to experimentally test the potential of soils differing in plant community history to suppress the pathogen Rhizoctonia solani. The results indicate that plant communities shape soil-disease suppression via changes in abiotic soil properties and the abundance of bacterial groups including species of the genera Actinomyces, Bacillus and Pseudomonas. Further, the results suggest that pairwise interactions between specific plant species strongly affect soil suppressiveness. Using structural equation modelling, we provide a pathway orientated framework showing how the complex interactions between plants, soil and microorganisms jointly shape soil suppressiveness. Our results stress the importance of plant community composition as a determinant of soil functioning, such as the disease suppressive potential of soils. PMID:27021053

  18. Potential applications of cryogenic technologies to plant genetic improvement and pathogen eradication.

    PubMed

    Wang, Biao; Wang, Ren-Rui; Cui, Zhen-Hua; Bi, Wen-Lu; Li, Jing-Wei; Li, Bai-Quan; Ozudogru, Elif Aylin; Volk, Gayle M; Wang, Qiao-Chun

    2014-01-01

    Rapid increases in human populations provide a great challenge to ensure that adequate quantities of food are available. Sustainable development of agricultural production by breeding more productive cultivars and by increasing the productive potential of existing cultivars can help meet this demand. The present paper provides information on the potential uses of cryogenic techniques in ensuring food security, including: (1) long-term conservation of a diverse germplasm and successful establishment of cryo-banks; (2) maintenance of the regenerative ability of embryogenic tissues that are frequently the target for genetic transformation; (3) enhancement of genetic transformation and plant regeneration of transformed cells, and safe, long-term conservation for transgenic materials; (4) production and maintenance of viable protoplasts for transformation and somatic hybridization; and (5) efficient production of pathogen-free plants. These roles demonstrate that cryogenic technologies offer opportunities to ensure food security.

  19. Promote potential applications of nanoparticles as respiratory drug carrier: insights from molecular dynamics simulations

    NASA Astrophysics Data System (ADS)

    Lin, Xubo; Bai, Tingting; Zuo, Yi Y.; Gu, Ning

    2014-02-01

    Nanoparticles (NPs) show great promises in biomedical applications as the respiratory drug carrier system. Once reaching the alveolar region, NPs first interact with the pulmonary surfactant (PS) film, which serves as the first biological barrier and plays an important role in maintaining the normal respiratory mechanics. Therefore, understanding the interactions between NPs and PS can help promote the NP-based respiratory drug carrier systems. Using coarse-grained molecular dynamics simulations, we studied the effect of rigid spherical NPs with different hydrophobicity and sizes on a dipalmitoylphosphatidylcholine (DPPC) monolayer at the air-water interface. Four different NPs were considered, including hydrophilic and hydrophobic NPs, each with two diameters of 3 nm and 5 nm (the sizes are comparable to that of generation 3 and 5 PAMAM dendrimers, which have been widely used for nanoscale drug carrier systems). Our simulations showed that hydrophilic NPs can readily penetrate into the aqueous phase with little or no disturbance on the DPPC monolayer. However, hydrophobic NPs tend to induce large structural disruptions, thus inhibiting the normal phase transition of the DPPC monolayer upon film compression. Our simulations also showed that this inhibitory effect of hydrophobic NPs can be mitigated through PEGylation. Our results provide useful guidelines for molecular design of NPs as carrier systems for pulmonary drug delivery.Nanoparticles (NPs) show great promises in biomedical applications as the respiratory drug carrier system. Once reaching the alveolar region, NPs first interact with the pulmonary surfactant (PS) film, which serves as the first biological barrier and plays an important role in maintaining the normal respiratory mechanics. Therefore, understanding the interactions between NPs and PS can help promote the NP-based respiratory drug carrier systems. Using coarse-grained molecular dynamics simulations, we studied the effect of rigid spherical NPs

  20. Pathogen Loading From Canada Geese Faeces in Freshwater: Potential Risks to Human Health Through Recreational Water Exposure.

    PubMed

    Gorham, T J; Lee, J

    2016-05-01

    Canada geese (Branta canadensis) faeces have been shown to contain pathogenic protozoa and bacteria in numerous studies over the past 15 years. Further, increases in both the Canada geese populations and their ideal habitat requirements in the United States (US) translate to a greater presence of these human pathogens in public areas, such as recreational freshwater beaches. Combining these factors, the potential health risk posed by Canada geese faeces at freshwater beaches presents an emerging public health issue that warrants further study. Here, literature concerning human pathogens in Canada geese faeces is reviewed and the potential impacts these pathogens may have on human health are discussed. Pathogens of potential concern include Campylobacter jejuni, Salmonella Typhimurium, Listeria monocytogenes, Helicobacter canadensis, Arcobacter spp., Enterohemorragic Escherichia coli pathogenic strains, Chlamydia psitacci, Cryptosporidium parvum and Giardia lamblia. Scenarios presenting potential exposure to pathogens eluted from faeces include bathers swimming in lakes, children playing with wet and dry sand impacted by geese droppings and other common recreational activities associated with public beaches. Recent recreational water-associated disease outbreaks in the US support the plausibility for some of these pathogens, including Cryptosporidium spp. and C. jejuni, to cause human illness in this setting. In view of these findings and the uncertainties associated with the real health risk posed by Canada geese faecal pathogens to users of freshwater lakes, it is recommended that beach managers use microbial source tracking and conduct a quantitative microbial risk assessment to analyse the local impact of Canada geese on microbial water quality during their decision-making process in beach and watershed management.

  1. Experimental infection of T4 Acanthamoeba genotype determines the pathogenic potential.

    PubMed

    Alves, Daniella de Sousa Mendes Moreira; Moraes, Aline Silva; Alves, Luciano Moreira; Gurgel-Gonçalves, Rodrigo; Lino Junior, Ruy de Souza; Cuba-Cuba, César Augusto; Vinaud, Marina Clare

    2016-09-01

    T4 is the Acanthamoeba genotype most related to cases of granulomatous amoebic encephalitis (GAE) in immunocompromised patients and of keratitis in contact lens wearers. The determination of the pathogenic potential of Acanthamoeba clinical and environmental isolates using experimental models is extremely important to elucidate the capacity of free-living organisms to establish and cause disease in hosts. The aim of this study was to compare and evaluate the histopathology and culture between two different routes of experimental infection of T4 Acanthamoeba isolated from environmental and clinical source in mice (intracranial and intraperitoneal). Swiss isogenic healthy mice were inoculated with 10(4) trophozoites by intracranial (IC) and intraperitoneal (IP) routes and observed during 21 days. The brains from animals inoculated by the IC route were collected and from the animals of the IP inoculation group, the brains, livers, kidneys, spleens, and lungs were removed. The organs were prepared and appropriately divided to be evaluated with histopathology and culture. There was no significant difference between the inoculation routes in terms of isolates recovery (χ(2) = 0.09; p = 0.76). In the IC group, isolate recovery rate was significantly higher in histopathology than the one achieved by culture (χ(2) = 6.45; p < 0.01). Experimental infection revealed that all isolates inoculated could be considered invasive because it was possible to recover evolutive forms of Acanthamoeba in both routes. This work represents the first in vivo pathogenicity assay of primary isolation source in Central region of Brazil showing in vivo pathogenicity and hematogenous spread capacity of these protozoa, improving the knowledge on free-living amoebae isolates.

  2. Evaluation of Innate Immune Biomarkers in Saliva for Diagnostic Potential of Bacterial and Viral Respiratory Infection

    DTIC Science & Technology

    2014-02-03

    infection and genetic disease (4). Similar to serum, saliva contains electrolytes, proteins, nucleic acids, and cells of epithelial and immune origin...which play a role in B-cell differentiation and activation (11, 12). While similar immune pathways are activated in response to viral infections... role in diagnostics for detection of infection and disease. Because the clinical symptoms of viral and bacterial respiratory infections are very

  3. Promote potential applications of nanoparticles as respiratory drug carrier: insights from molecular dynamics simulations.

    PubMed

    Lin, Xubo; Bai, Tingting; Zuo, Yi Y; Gu, Ning

    2014-03-07

    Nanoparticles (NPs) show great promises in biomedical applications as the respiratory drug carrier system. Once reaching the alveolar region, NPs first interact with the pulmonary surfactant (PS) film, which serves as the first biological barrier and plays an important role in maintaining the normal respiratory mechanics. Therefore, understanding the interactions between NPs and PS can help promote the NP-based respiratory drug carrier systems. Using coarse-grained molecular dynamics simulations, we studied the effect of rigid spherical NPs with different hydrophobicity and sizes on a dipalmitoylphosphatidylcholine (DPPC) monolayer at the air-water interface. Four different NPs were considered, including hydrophilic and hydrophobic NPs, each with two diameters of 3 nm and 5 nm (the sizes are comparable to that of generation 3 and 5 PAMAM dendrimers, which have been widely used for nanoscale drug carrier systems). Our simulations showed that hydrophilic NPs can readily penetrate into the aqueous phase with little or no disturbance on the DPPC monolayer. However, hydrophobic NPs tend to induce large structural disruptions, thus inhibiting the normal phase transition of the DPPC monolayer upon film compression. Our simulations also showed that this inhibitory effect of hydrophobic NPs can be mitigated through PEGylation. Our results provide useful guidelines for molecular design of NPs as carrier systems for pulmonary drug delivery.

  4. Potential therapeutic implications of new insights into respiratory syncytial virus disease.

    PubMed

    Openshaw, Peter J M

    2002-01-01

    Viral bronchiolitis is the most common cause of hospitalization in infants under 6 months of age, and 70% of all cases of bronchiolitis are caused by respiratory syncytial virus (RSV). Early RSV infection is associated with respiratory problems such as asthma and wheezing later in life. RSV infection is usually spread by contaminated secretions and infects the upper then lower respiratory tracts. Infected cells release proinflammatory cytokines and chemokines, including IL-1, tumor necrosis factor-alpha, IL-6, and IL-8. These activate other cells and recruit inflammatory cells, including macrophages, neutrophils, eosinophils, and T lymphocytes, into the airway wall and surrounding tissues. The pattern of cytokine production by T lymphocytes can be biased toward 'T-helper-1' or 'T-helper-2' cytokines, depending on the local immunologic environment, infection history, and host genetics. T-helper-1 responses are generally efficient in antiviral defense, but young infants have an inherent bias toward T-helper-2 responses. The ideal intervention for RSV infection would be preventive, but the options are currently limited. Vaccines based on protein subunits, live attenuated strains of RSV, DNA vaccines, and synthetic peptides are being developed; passive antibody therapy is at present impractical in otherwise healthy children. Effective vaccines for use in neonates continue to be elusive but simply delaying infection beyond the first 6 months of life might reduce the delayed morbidity associated with infantile disease.

  5. Influenza A virus transmission via respiratory aerosols or droplets as it relates to pandemic potential

    PubMed Central

    Richard, Mathilde; Fouchier, Ron A.M.

    2015-01-01

    Many respiratory viruses of humans originate from animals. For instance, there are now eight paramyxoviruses, four coronaviruses and four orthomxoviruses that cause recurrent epidemics in humans but were once confined to other hosts. In the last decade, several members of the same virus families have jumped the species barrier from animals to humans. Fortunately, these viruses have not become established in humans, because they lacked the ability of sustained transmission between humans. However, these outbreaks highlighted the lack of understanding of what makes a virus transmissible. In part triggered by the relatively high frequency of occurrence of influenza A virus zoonoses and pandemics, the influenza research community has started to investigate the viral genetic and biological traits that drive virus transmission via aerosols or respiratory droplets between mammals. Here we summarize recent discoveries on the genetic and phenotypic traits required for airborne transmission of zoonotic influenza viruses of subtypes H5, H7 and H9 and pandemic viruses of subtypes H1, H2 and H3. Increased understanding of the determinants and mechanisms of respiratory virus transmission is not only key from a basic scientific perspective, but may also aid in assessing the risks posed by zoonotic viruses to human health, and preparedness for such risks. PMID:26385895

  6. Influenza virus respiratory infection and transmission following ocular inoculation in ferrets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    While influenza viruses are a common respiratory pathogen, sporadic reports of conjunctivitis following human infection demonstrates the ability of this virus to cause disease outside of the respiratory tract. The ocular surface represents both a potential site of virus replication and a portal of e...

  7. Saffold Cardioviruses of 3 Lineages in Children with Respiratory Tract Infections, Beijing, China

    PubMed Central

    Ren, Lili; Gonzalez, Richard; Xie, Zhengde; Xiao, Yan; Li, Yongjun; Liu, Chunyan; Chen, Lan; Yang, Qingqing; Vernet, Guy; Paranhos-Baccalà, Gláucia; Jin, Qi; Shen, Kunling

    2010-01-01

    To clarify the potential for respiratory transmission of Saffold cardiovirus (SAFV) and characterize the pathogen, we analyzed respiratory specimens from 1,558 pediatric patients in Beijing. We detected SAFV in 7 (0.5%) patients and identified lineages 1–3. However, because 3 patients had co-infections, we could not definitively say SAFV caused disease. PMID:20587195

  8. The 15N and 46R Residues of Highly Pathogenic Porcine Reproductive and Respiratory Syndrome Virus Nucleocapsid Protein Enhance Regulatory T Lymphocytes Proliferation

    PubMed Central

    Bai, Juan; Li, Yufeng; Zhang, Qiaoya; Jiang, Ping

    2015-01-01

    Porcine reproductive and respiratory syndrome virus (PRRSV) negatively modulates host immune responses, resulting in persistent infection and immunosuppression. PRRSV infection increases the number of PRRSV-specific regulatory T lymphocytes (Tregs) in infected pigs. However, the target antigens for Tregs proliferation in PRRSV infection have not been fully understood. In this study, we demonstrated that the highly pathogenic PRRSV (HP-PRRSV) induced more CD4+CD25+Foxp3+ Tregs than classical PRRSV (C-PRRSV) strain. Of the recombinant GP5, M and N proteins of HP-PRRSV expressed in baculovirus expression systems, only N protein induced Tregs proliferation. The Tregs assays showed that three amino-acid regions, 15–21, 42–48 and 88–94, in N protein played an important role in induction of Tregs proliferation with synthetic peptides covering the whole length of N protein. By using reverse genetic methods, it was firstly found that the 15N and 46R residues in PRRSV N protein were critical for induction of Tregs proliferation. The phenotype of induced Tregs closely resembled that of transforming-growth-factor-β-secreting T helper 3 Tregs in swine. These data should be useful for understanding the mechanism of immunity to PRRSV and development of infection control strategies in the future. PMID:26397116

  9. Public preferences for vaccination programmes during pandemics caused by pathogens transmitted through respiratory droplets - a discrete choice experiment in four European countries, 2013.

    PubMed

    Determann, Domino; Korfage, Ida J; Fagerlin, Angela; Steyerberg, Ewout W; Bliemer, Michiel C; Voeten, Helene A; Richardus, Jan Hendrik; Lambooij, Mattijs S; de Bekker-Grob, Esther W

    2016-06-02

    This study aims to quantify and compare preferences of citizens from different European countries for vaccination programme characteristics during pandemics, caused by pathogens which are transmitted through respiratory droplets. Internet panel members, nationally representative based on age, sex, educational level and region, of four European Union Member States (Netherlands, Poland, Spain, and Sweden, n = 2,068) completed an online discrete choice experiment. These countries, from different geographical areas of Europe, were chosen because of the availability of high-quality Internet panels and because of the cooperation between members of the project entitled Effective Communication in Outbreak Management: development of an evidence-based tool for Europe (ECOM). Data were analysed using panel latent class regression models. In the case of a severe pandemic scenario, vaccine effectiveness was the most important characteristic determining vaccination preference in all countries, followed by the body that advises on vaccination. In Sweden, the advice of family and/or friends and the advice of physicians strongly affected vaccine preferences, in contrast to Poland and Spain, where the advice of (international) health authorities was more decisive. Irrespective of pandemic scenario or vaccination programme characteristics, the predicted vaccination uptakes were lowest in Sweden, and highest in Poland. To increase vaccination uptake during future pandemics, the responsible authorities should align with other important stakeholders in the country and communicate in a coordinated manner.

  10. Highly Pathogenic Porcine Reproductive and Respiratory Syndrome Virus Nsp4 Cleaves VISA to Impair Antiviral Responses Mediated by RIG-I-like Receptors

    PubMed Central

    Huang, Chen; Du, Yinping; Yu, Zhibin; Zhang, Qiong; Liu, Yihao; Tang, Jun; Shi, Jishu; Feng, Wen-hai

    2016-01-01

    Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most significant etiological agents in the swine industry worldwide. It has been reported that PRRSV infection can modulate host immune responses, and innate immune evasion is thought to play a vital role in PRRSV pathogenesis. In this study, we demonstrated that highly pathogenic PRRSV (HP-PRRSV) infection specifically down-regulated virus-induced signaling adaptor (VISA), a unique adaptor molecule that is essential for retinoic acid induced gene-I (RIG-I) and melanoma differentiation associated gene 5 (MDA5) signal transduction. Moreover, we verified that nsp4 inhibited IRF3 activation induced by signaling molecules, including RIG-I, MDA5, VISA, and TBK1, but not IRF3. Subsequently, we demonstrated that HP-PRRSV nsp4 down-regulated VISA and suppressed type I IFN induction. Importantly, VISA was cleaved by nsp4 and released from mitochondrial membrane, which interrupted the downstream signaling of VISA. However, catalytically inactive mutant of nsp4 abolished its ability to cleave VISA. Interestingly, nsp4 of typical PRRSV strain CH-1a had no effect on VISA. Taken together, these findings reveal a strategy evolved by HP-PRRSV to counteract anti-viral innate immune signaling, which complements the known PRRSV-mediated immune-evasion mechanisms. PMID:27329948

  11. Health assessment and seroepidemiologic survey of potential pathogens in wild Antillean manatees (Trichechus manatus manatus)

    USGS Publications Warehouse

    Sulzner, Kathryn; Johnson, Christine Kreuder; Bonde, Robert K.; Gomez, Nicole Auil; Powell, James; Nielsen, Klaus; Luttrell, M. Page; Osterhaus, A.D.M.E.; Aguirre, A. Alonso

    2012-01-01

    The Antillean manatee (Trichechus manatus manatus), a subspecies of the West Indian manatee, inhabits fresh, brackish, and warm coastal waters distributed along the eastern border of Central America, the northern coast of South America, and throughout the Wider Caribbean Region. Threatened primarily by human encroachment, poaching, and habitat degradation, Antillean manatees are listed as endangered by the International Union for the Conservation of Nature. The impact of disease on population viability remains unknown in spite of concerns surrounding the species' ability to rebound from a population crash should an epizootic occur. To gain insight on the baseline health of this subspecies, a total of 191 blood samples were collected opportunistically from wild Antillean manatees in Belize between 1997 and 2009. Hematologic and biochemical reference intervals were established, and antibody prevalence to eight pathogens with zoonotic potential was determined. Age was found to be a significant factor of variation in mean blood values, whereas sex, capture site, and season contributed less to overall differences in parameter values. Negative antibody titers were reported for all pathogens surveyed except for Leptospira bratislava, L. canicola, and L. icterohemorrhagiae, Toxoplasma gondii, and morbillivirus. As part of comprehensive health assessment in manatees from Belize, this study will serve as a benchmark aiding in early disease detection and in the discernment of important epidemiologic patterns in the manatees of this region. Additionally, it will provide some of the initial tools to explore the broader application of manatees as sentinel species of nearshore ecosystem health.

  12. Health Assessment and Seroepidemiologic Survey of Potential Pathogens in Wild Antillean Manatees (Trichechus manatus manatus)

    PubMed Central

    Sulzner, Kathryn; Kreuder Johnson, Christine; Bonde, Robert K.; Auil Gomez, Nicole; Powell, James; Nielsen, Klaus; Luttrell, M. Page; Osterhaus, A. D. M. E.; Aguirre, A. Alonso

    2012-01-01

    The Antillean manatee (Trichechus manatus manatus), a subspecies of the West Indian manatee, inhabits fresh, brackish, and warm coastal waters distributed along the eastern border of Central America, the northern coast of South America, and throughout the Wider Caribbean Region. Threatened primarily by human encroachment, poaching, and habitat degradation, Antillean manatees are listed as endangered by the International Union for the Conservation of Nature. The impact of disease on population viability remains unknown in spite of concerns surrounding the species’ ability to rebound from a population crash should an epizootic occur. To gain insight on the baseline health of this subspecies, a total of 191 blood samples were collected opportunistically from wild Antillean manatees in Belize between 1997 and 2009. Hematologic and biochemical reference intervals were established, and antibody prevalence to eight pathogens with zoonotic potential was determined. Age was found to be a significant factor of variation in mean blood values, whereas sex, capture site, and season contributed less to overall differences in parameter values. Negative antibody titers were reported for all pathogens surveyed except for Leptospira bratislava, L. canicola, and L. icterohemorrhagiae, Toxoplasma gondii, and morbillivirus. As part of comprehensive health assessment in manatees from Belize, this study will serve as a benchmark aiding in early disease detection and in the discernment of important epidemiologic patterns in the manatees of this region. Additionally, it will provide some of the initial tools to explore the broader application of manatees as sentinel species of nearshore ecosystem health. PMID:22984521

  13. Acanthamoeba polyphaga, a potential environmental vector for the transmission of food-borne and opportunistic pathogens.

    PubMed

    Anacarso, Immacolata; de Niederhäusern, Simona; Messi, Patrizia; Guerrieri, Elisa; Iseppi, Ramona; Sabia, Carla; Bondi, Moreno

    2012-06-01

    The endosymbiotic relationship could represent for many bacteria an important condition favouring their spread in the environment and in foods. For this purpose we studied the behaviour of some food-borne and opportunistic pathogens (Listeria monocytogenes, Staphylococcus aureus, Enterococcus faecalis, Salmonella enterica serovar Enteritidis, Aeromonas hydrophila, Yersinia enterocolitica) when internalized in Acanthamoeba polyphaga. Our results confirm the capability of the bacteria tested to grow within amoebal hosts. We can observe two types of interactions of the bacteria internalized in A. polyphaga. The first type, showed by Y. enterocolitica and A. hydrophila, was characterized by an early replication, probably followed by the killing and digestion of the bacteria. The second type, showed by E. faecalis and S. aureus was characterized by the persistence and grow inside the host without lysis. Lastly, when amoebae were co-cultured with L. monocytogenes and S. Enteritidis, an eclipse phase followed by an active intracellular growth was observed, suggesting a third type of predator-prey trend. The extracellular count in presence of A. polyphaga, as a result of an intracellular multiplication and subsequent release, was characterized by an increase of E. faecalis, S. aureus, L. monocytogenes and S. Enteritidis, and by a low or absent cell count for Y. enterocolitica and A. hydrophila. Our study suggests that the investigated food-borne and opportunistic pathogens are, in most cases, able to interact with A. polyphaga, to intracellularly replicate and, lastly, to be potentially spread in the environment, underlining the possible role of this protozoan in food contamination.

  14. A review on the inhibitory potential of Nigella sativa against pathogenic and toxigenic fungi.

    PubMed

    Shokri, Hojjatollah

    2016-01-01

    Nigella sativa (N. sativa) grows in various parts of the world, particularly in Iran. It has been traditionally used as a folk remedy to treat a number of diseases. The seeds of this plant contain moisture, proteins, carbohydrates, crude fiber, alkaloids, saponins, ash, fixed oils and essential oil. The major components of the essential oil are thymoquinone, p-cymene, trans-anethole, 2-methyl-5(1-methyl ethyl)-Bicyclo[3.1.0]hex-2-en and γ-terpinene. So far, several pharmacological effects such as anti-oxidant, anti-inflammatory, anti-cancer and anti-microbial have been reported for N. sativa or its active compounds. Thymoquinone, thymohydroquinone and thymol are the most active constituents which have different beneficial properties. The oil, extracts and some of N. sativa active components possessed moderate in vitro and in vivo inhibitory activity against pathogenic yeasts, dermatophytes, non-dermatophytic filamentous fungi and aflatoxin-producing fungi. The main morphological changes of pathogenic and toxigenic fungi treated with N. sativa oil were observed in the cell wall, plasma membrane and membranous organelles, particularly in the nuclei and mitochondria. Although this review represents first step in the search for a new anti-fungal drug, the full potential of N. sativa as a fungitoxic agent has not been exploited and necessitates further investigations.

  15. Metabolomics Analysis Reveals Specific Novel Tetrapeptide and Potential Anti-Inflammatory Metabolites in Pathogenic Aspergillus species

    PubMed Central

    Lee, Kim-Chung; Tam, Emily W. T.; Lo, Ka-Ching; Tsang, Alan K. L.; Lau, Candy C. Y.; To, Kelvin K. W.; Chan, Jasper F. W.; Lam, Ching-Wan; Yuen, Kwok-Yung; Lau, Susanna K. P.; Woo, Patrick C. Y.

    2015-01-01

    Infections related to Aspergillus species have emerged to become an important focus in infectious diseases, as a result of the increasing use of immunosuppressive agents and high fatality associated with invasive aspergillosis. However, laboratory diagnosis of Aspergillus infections remains difficult. In this study, by comparing the metabolomic profiles of the culture supernatants of 30 strains of six pathogenic Aspergillus species (A. fumigatus, A. flavus, A. niger, A. terreus, A. nomius and A. tamarii) and 31 strains of 10 non-Aspergillus fungi, eight compounds present in all strains of the six Aspergillus species but not in any strain of the non-Aspergillus fungi were observed. One of the eight compounds, Leu–Glu–Leu–Glu, is a novel tetrapeptide and represents the first linear tetrapeptide observed in Aspergillus species, which we propose to be named aspergitide. Two other closely related Aspergillus-specific compounds, hydroxy-(sulfooxy)benzoic acid and (sulfooxy)benzoic acid, may possess anti-inflammatory properties, as 2-(sulfooxy)benzoic acid possesses a structure similar to those of aspirin [2-(acetoxy)benzoic acid] and salicylic acid (2-hydroxybenzoic acid). Further studies to examine the potentials of these Aspergillus-specific compounds for laboratory diagnosis of aspergillosis are warranted and further experiments will reveal whether Leu–Glu–Leu–Glu, hydroxy-(sulfooxy)benzoic acid and (sulfooxy)benzoic acid are virulent factors of the pathogenic Aspergillus species. PMID:26090713

  16. Leptospira wolffii, a potential new pathogenic Leptospira species detected in human, sheep and dog.

    PubMed

    Zakeri, Sedigheh; Khorami, Nargess; Ganji, Zahra F; Sepahian, Neda; Malmasi, Abdol-Ali; Gouya, Mohammad Mehdi; Djadid, Navid D

    2010-03-01

    Leptospirosis is the most common zoonotic disease, which is transmitted to humans through contaminated water or direct exposure to the urine of infected animals. In this study, the presence and prevalence of Leptospira species in the infected samples of human (n=369) and sheep (n=75) sera and also dogs' urine (n=150), collected from four provinces of Iran, were investigated by using nested-PCR/RFLP assay followed by sequencing analysis. Nested-PCR assay detected that 98/369 (26.5%) human, 13/75 (17.33%) of sheep's sera and 33/150 (22%) dogs' urine samples were positive for Leptospira DNA. RFLP assay detected that all positive cases had either pathogenic or intermediate Leptospira species. By sequence analysis, Leptospira interrogans was the most prevalent species among the examined samples of human (53/82, 64.6%) and sheep (11/13, 84.6%). However, in dog samples, Leptospira wolffii (27/29, 93.1%) was detected for the first time and was the dominant species. The presence of L. wolffii with 100% identity in clinical human samples and animals suspected with Leptospira may provide evidence for circulation of L. wolffii and its role in transmission cycle within human and animal hosts. In addition, this species can be potentially pathogenic to human and probably animal hosts. A large epidemiology survey would be needed to define the presence and the prevalence of this species in global endemic regions.

  17. Birds as potential reservoirs of tick-borne pathogens: first evidence of bacteraemia with Rickettsia helvetica

    PubMed Central

    2014-01-01

    Background Birds have long been known as carriers of ticks, but data from the literature are lacking on their role as a reservoir in the epidemiology of certain tick-borne disease-causing agents. Therefore, the aim of this study was to evaluate the presence of three emerging, zoonotic tick-borne pathogens in blood samples and ticks of birds and to assess the impact of feeding location preference and migration distance of bird species on their tick infestation. Methods Blood samples and ticks of birds were analysed with TaqMan real-time PCRs and conventional PCR followed by sequencing. Results During the spring and autumn bird migrations, 128 blood samples and 140 ticks (Ixodes ricinus, Haemaphysalis concinna and a Hyalomma specimen) were collected from birds belonging to 16 species. The prevalence of tick infestation and the presence of tick species were related to the feeding and migration habits of avian hosts. Birds were shown to be bacteraemic with Rickettsia helvetica and Anaplasma phagocytophilum, but not with Candidatus Neoehrlichia mikurensis. The prevalence of rickettsiae was high (51.4%) in ticks, suggesting that some of them may have acquired their infection from their avian host. Conclusion Based on the present results birds are potential reservoirs of both I. ricinus transmitted zoonotic pathogens, R. helvetica and A. phagocytophilum, but their epidemiological role appears to be less important concerning the latter, at least in Central Europe. PMID:24679245

  18. Bovine mastitis disease/pathogenicity: evidence of the potential role of microbial biofilms.

    PubMed

    Gomes, Fernanda; Saavedra, Maria José; Henriques, Mariana

    2016-04-01

    Bovine mastitis (BM) is a disease with high incidence worldwide and one of the most relevant bovine pathologies and the most costly to the dairy industry. BM is an inflammation of the udder and represents one of the most difficult veterinary diseases to control. Biofilm formation is considered a selective advantage for pathogens causing mastitis, facilitating bacterial persistence in the udder. In fact, recently some authors drew attention to the biofilm formation ability presented by several mastitis causing pathogens and to its possible relation with recurrent mastitis infections and with the increased resistance to antimicrobial agents and host immune defence system. Actually, up to now, several researchers reported the potential role of cells in this mode of growth in the previous facts mentioned. As a consequence of the presence of biofilms, the infection here focused is more difficult to treat and eradicate, making this problem a more relevant pressing issue. Thus, we believe that a deeper knowledge of these structures in mastitis can help to determine the best control strategy to be used in veterinary practice in order to reduce losses in the dairy industry and to ensure milk safety and quality. The aim of this paper was to review the existing research and consequently to provide an overview of the role of biofilms in BM infections.

  19. A review on the inhibitory potential of Nigella sativa against pathogenic and toxigenic fungi

    PubMed Central

    Shokri, Hojjatollah

    2016-01-01

    Nigella sativa (N. sativa) grows in various parts of the world, particularly in Iran. It has been traditionally used as a folk remedy to treat a number of diseases. The seeds of this plant contain moisture, proteins, carbohydrates, crude fiber, alkaloids, saponins, ash, fixed oils and essential oil. The major components of the essential oil are thymoquinone, p-cymene, trans-anethole, 2-methyl-5(1-methyl ethyl)-Bicyclo[3.1.0]hex-2-en and γ-terpinene. So far, several pharmacological effects such as anti-oxidant, anti-inflammatory, anti-cancer and anti-microbial have been reported for N. sativa or its active compounds. Thymoquinone, thymohydroquinone and thymol are the most active constituents which have different beneficial properties. The oil, extracts and some of N. sativa active components possessed moderate in vitro and in vivo inhibitory activity against pathogenic yeasts, dermatophytes, non-dermatophytic filamentous fungi and aflatoxin-producing fungi. The main morphological changes of pathogenic and toxigenic fungi treated with N. sativa oil were observed in the cell wall, plasma membrane and membranous organelles, particularly in the nuclei and mitochondria. Although this review represents first step in the search for a new anti-fungal drug, the full potential of N. sativa as a fungitoxic agent has not been exploited and necessitates further investigations. PMID:27247919

  20. Health assessment and seroepidemiologic survey of potential pathogens in wild Antillean manatees (Trichechus manatus manatus).

    PubMed

    Sulzner, Kathryn; Kreuder Johnson, Christine; Bonde, Robert K; Auil Gomez, Nicole; Powell, James; Nielsen, Klaus; Luttrell, M Page; Osterhaus, A D M E; Aguirre, A Alonso

    2012-01-01

    The Antillean manatee (Trichechus manatus manatus), a subspecies of the West Indian manatee, inhabits fresh, brackish, and warm coastal waters distributed along the eastern border of Central America, the northern coast of South America, and throughout the Wider Caribbean Region. Threatened primarily by human encroachment, poaching, and habitat degradation, Antillean manatees are listed as endangered by the International Union for the Conservation of Nature. The impact of disease on population viability remains unknown in spite of concerns surrounding the species' ability to rebound from a population crash should an epizootic occur. To gain insight on the baseline health of this subspecies, a total of 191 blood samples were collected opportunistically from wild Antillean manatees in Belize between 1997 and 2009. Hematologic and biochemical reference intervals were established, and antibody prevalence to eight pathogens with zoonotic potential was determined. Age was found to be a significant factor of variation in mean blood values, whereas sex, capture site, and season contributed less to overall differences in parameter values. Negative antibody titers were reported for all pathogens surveyed except for Leptospira bratislava, L. canicola, and L. icterohemorrhagiae, Toxoplasma gondii, and morbillivirus. As part of comprehensive health assessment in manatees from Belize, this study will serve as a benchmark aiding in early disease detection and in the discernment of important epidemiologic patterns in the manatees of this region. Additionally, it will provide some of the initial tools to explore the broader application of manatees as sentinel species of nearshore ecosystem health.

  1. Impact of water potential on growth and germination of Fusarium solani soilborne pathogen of peanut

    PubMed Central

    Palacios, Sofia; Casasnovas, Francisco; Ramirez, María L.; Reynoso, María. M.; Torres, Adriana M.

    2014-01-01

    Studies were conducted to determine the effect of osmotic and matric stress on germination and growth of two Fusarium solani strains, the etiological agent responsible of peanut brown root rot. Both strains had similar osmotic and matric potential ranges that allowed growth, being the latter one narrower. F. solani showed the ability to grow down to −14 MPa at 25 °C in non-ionic modified osmotic medium, while under matric stress this was limited to −8.4 MPa at 25 °C. However, both strains were seen to respond differently to decreasing osmotic and matric potentials, during early stages of germination. One strain (RC 338) showed to be more sensitive to matric than osmotic (non ionic) and the other one (RC 386) showed to be more sensitive to osmotic than matric imposed water stress. After 24 h of incubation, both isolates behaved similarly. The minimum water potential for germination was −8.4 MPa on glycerol amended media and −5.6 MPa for NaCl and PEG amended media, respectively. The knowledge of the water potential range which allow mycelia growth and spore germination of F. solani provides an inside to the likely behaviour of this devastating soilborne plant pathogen in nature and has important practical implications. PMID:25477950

  2. Impact of water potential on growth and germination of Fusarium solani soilborne pathogen of peanut.

    PubMed

    Palacios, Sofia; Casasnovas, Francisco; Ramirez, María L; Reynoso, María M; Torres, Adriana M

    2014-01-01

    Studies were conducted to determine the effect of osmotic and matric stress on germination and growth of two Fusarium solani strains, the etiological agent responsible of peanut brown root rot. Both strains had similar osmotic and matric potential ranges that allowed growth, being the latter one narrower. F. solani showed the ability to grow down to -14 MPa at 25 °C in non-ionic modified osmotic medium, while under matric stress this was limited to -8.4 MPa at 25 °C. However, both strains were seen to respond differently to decreasing osmotic and matric potentials, during early stages of germination. One strain (RC 338) showed to be more sensitive to matric than osmotic (non ionic) and the other one (RC 386) showed to be more sensitive to osmotic than matric imposed water stress. After 24 h of incubation, both isolates behaved similarly. The minimum water potential for germination was -8.4 MPa on glycerol amended media and -5.6 MPa for NaCl and PEG amended media, respectively. The knowledge of the water potential range which allow mycelia growth and spore germination of F. solani provides an inside to the likely behaviour of this devastating soilborne plant pathogen in nature and has important practical implications.

  3. Diversity of potential pathogenicity and biofilm formation among Burkholderia cepacia complex water, clinical, and agricultural isolates in China.

    PubMed

    Ibrahim, Muhammad; Tang, Qiaomei; Shi, Yu; Almoneafy, Abdulwareth; Fang, Yuan; Xu, Liuhu; Li, Wen; Li, Bin; Xie, Guan-Lin

    2012-05-01

    A collection of 70 Burkholderia cepacia complex isolates, recovered from clinical, water, and agricultural resources in China in our previous studies, were tested to assess their potential pathogenicity and association of biofilm formation with pathogenicity. The pathogenicity was tested in the alternative infection models alfalfa, detached lettuce midrib, Galleria mellonella (wax moth), rat agar bead, and lettuce intact leaves. Severe to moderate pathogenicity were observed for isolates of clinical and water origin compared to agricultural isolates, with the exception of a few clinical isolates exhibiting reduced pathogenicity. Virulent isolates persisted in rat lungs until 21 days post infection causing histopathological changes like inflammation, while in lettuce midrib tissues invasion, localization, and replication of bacteria were observed. Biofilm formation ability was also documented in high frequency among water and clinical virulent isolates compared to agricultural isolates. Although variations in pathogenicity were observed for a few isolates, results obtained from different model systems including lettuce were consistent. Our studies indicate that water and clinical isolates showed severe virulence and strong biofilm formation ability compared to agricultural isolates. The results also show lettuce as a promising infection model not only to study the pathogenicity factors used by Bcc bacteria but also for characterization the in vivo transcriptional profile for different niches adaptation of this opportunistic pathogen.

  4. RARE OCCURRENCE OF HETEROTROPHIC BACTERIA WITH PATHOGENIC POTENTIAL IN POTABLE WATER

    EPA Science Inventory

    Since the discovery of Legionella pneumophila, an opportunistic pathogen that is indigenous to water, microbiologists have speculated that there may be other opportunistic pathogens among the numerous heterotrophic bacteria found in potable water. The USEPA developed a series of...

  5. New Insights on the Maternal Diet Induced-Hypertension: Potential Role of the Phenotypic Plasticity and Sympathetic-Respiratory Overactivity

    PubMed Central

    Costa-Silva, João H.; de Brito-Alves, José L.; Barros, Monique Assis de V.; Nogueira, Viviane Oliveira; Paulino-Silva, Kássya M.; de Oliveira-Lira, Allan; Nobre, Isabele G.; Fragoso, Jéssica; Leandro, Carol G.

    2015-01-01

    Systemic arterial hypertension (SAH) is an important risk factor for cardiovascular disease and affects worldwide population. Current environment including life style coupled with genetic programming have been attributed to the rising incidence of hypertension. Besides, environmental conditions during perinatal development such as maternal malnutrition can program changes in the integration among renal, neural, and endocrine system leading to hypertension. This phenomenon is termed phenotypic plasticity and refers to the adjustment of a phenotype in response to environmental stimuli without genetic change, following a novel or unusual input during development. Human and animal studies indicate that fetal exposure to an adverse maternal environment may alter the renal morphology and physiology that contribute to the development of hypertension. Recently, it has been shown that the maternal protein restriction alter the central control of SAH by a mechanism that include respiratory dysfunction and enhanced sympathetic-respiratory coupling at early life, which may contribute to adult hypertension. This review will address the new insights on the maternal diet induced-hypertension that include the potential role of the phenotypic plasticity, specifically the perinatal protein malnutrition, and sympathetic-respiratory overactivity. PMID:26635631

  6. Prospects for vaccination against the ticks of pets and the potential impact on pathogen transmission.

    PubMed

    de la Fuente, José; Villar, Margarita; Contreras, Marinela; Moreno-Cid, Juan A; Merino, Octavio; Pérez de la Lastra, José M; de la Fuente, Gabriela; Galindo, Ruth C

    2015-02-28

    Diseases transmitted by arthropod vectors such as ticks greatly impact human and animal health. In particular, many diseases of dogs and cats are potentially transmissible to people by arthropod vectors and therefore their control is important for the eradication of vector-borne diseases (VBD). Vaccination is an environmentally friendly alternative for vector control that allows control of several VBD by targeting their common vector. Recent results have shown that it is possible to use vector protective antigens for the control of arthropod vector infestations and pathogen infection. However, as reviewed in this paper, very little progress has been made for the control of ectoparasite infestations and VBD in pets using vaccination with vector protective antigens. The growing interaction between pets and people underlines the importance of developing new interventions for the monitoring and control of VBD.

  7. Polymerase chain reaction detection of potentially pathogenic free-living amoebae in dental units.

    PubMed

    Leduc, Annie; Gravel, Sabrina; Abikhzer, Jérémie; Roy, Stéphane; Barbeau, Jean

    2012-07-01

    Several genera of amoebae can be found in water from dental units and on the inner surface of waterlines. The presence of bacterial biofilms on these surfaces is thought to favor the proliferation of amoebae. Potentially pathogenic Acanthamoeba and Naegleria spp. may be an infection risk for patients through contact with open surgical sites or aerosolization. A polymerase chain reaction of DNA extracted from pelleted samples showed that Acanthamoeba spp. and Naegleria spp. were present in water from dental units, suction lines, and suction filters at the dental clinic of the Université de Montréal. Acanthamoeba spp. were detected in 24.2% of 66 samples and Naegleria spp. in 3.0%. We discuss the infection risk associated with these results.

  8. Potential pathogenic role of aggregative-adhering Corynebacterium diphtheriae of different clonal groups in endocarditis.

    PubMed

    Hirata Jr, R; Pereira, G A; Filardy, A A; Gomes, D L R; Damasco, P V; Rosa, A C P; Nagao, P E; Pimenta, F P; Mattos-Guaraldi, A L

    2008-11-01

    Invasive diseases caused by Corynebacterium diphtheriae have been described increasingly. Several reports indicate the destructive feature of endocarditis attributable to nontoxigenic strains. However, few reports have dealt with the pathogenicity of invasive strains. The present investigation demonstrates a phenotypic trait that may be used to identify potentially invasive strains. The study also draws attention to clinical and microbiological aspects observed in 5 cases of endocarditis due to C. diphtheriae that occurred outside Europe. Four cases occurred in female school-age children (7-14 years) treated at different hospitals in Rio de Janeiro, Brazil. All patients developed other complications including septicemia, renal failure and/or arthritis. Surgical treatment was performed on 2 patients for valve replacement. Lethality was observed in 40% of the cases. Microorganisms isolated from 5 blood samples and identified as C. diphtheriae subsp mitis (N = 4) and C. diphtheriae subsp gravis (N = 1) displayed an aggregative adherence pattern to HEp-2 cells and identical one-dimensional SDS-PAGE protein profiles. Aggregative-adhering invasive strains of C. diphtheriae showed 5 distinct RAPD profiles. Despite the clonal diversity, all 5 C. diphtheriae invasive isolates seemed to display special bacterial adhesive properties that may favor blood-barrier disruption and systemic dissemination of bacteria. In conclusion, blood isolates from patients with endocarditis exhibited a unique adhering pattern, suggesting a pathogenic role of aggregative-adhering C. diphtheriae of different clones in endocarditis. Accordingly, the aggregative-adherence pattern may be used as an indication of some invasive potential of C. diphtheriae strains.

  9. Potentially pathogenic Escherichia coli can form a biofilm under conditions relevant to the food production chain.

    PubMed

    Nesse, Live L; Sekse, Camilla; Berg, Kristin; Johannesen, Karianne C S; Solheim, Heidi; Vestby, Lene K; Urdahl, Anne Margrete

    2014-04-01

    The biofilm-producing abilities of potentially human-pathogenic serotypes of Escherichia coli from the ovine reservoir were studied at different temperatures and on different surfaces. A possible influence of the hydrophobicity of the bacterial cells, as well as the presence of two virulence factors, the Shiga toxin-encoding (Stx) bacteriophage and the eae gene, was also studied. A total of 99 E. coli isolates of serotypes O26:H11, O103:H2, and O103:H25 isolated from sheep feces were included. The results show that isolates of all three E. coli serotypes investigated can produce biofilm on stainless steel, glass, and polystyrene at 12, 20, and 37°C. There was a good general correlation between the results obtained on the different surfaces. E. coli O103:H2 isolates produced much more biofilm than those of the other two serotypes at all three temperatures. In addition, isolates of serotype O26:H11 produced more biofilm than those of O103:H25 at 37°C. The hydrophobicity of the isolates varied between serotypes and was also influenced by temperature. The results strongly indicated that hydrophobicity influenced the attachment of the bacteria rather than their ability to form biofilm once attached. Isolates with the eae gene produced less biofilm at 37°C than isolates without this gene. The presence of a Stx bacteriophage did not influence biofilm production. In conclusion, our results show that potentially human-pathogenic E. coli from the ovine reservoir can form biofilm on various surfaces and at several temperatures relevant for food production and handling.

  10. Potential of Pseudomonas putida PCI2 for the Protection of Tomato Plants Against Fungal Pathogens.

    PubMed

    Pastor, Nicolás; Masciarelli, Oscar; Fischer, Sonia; Luna, Virginia; Rovera, Marisa

    2016-09-01

    Tomato is one of the most economically attractive vegetable crops due to its high yields. Diseases cause significant losses in tomato production worldwide. We carried out Polymerase Chain Reaction studies to detect the presence of genes encoding antifungal compounds in the DNA of Pseudomonas putida strain PCI2. We also used liquid chromatography-electrospray tandem mass spectrometry to detect and quantify the production of compounds that increase the resistance of plants to diseases from culture supernatants of PCI2. In addition, we investigated the presence of 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase in PCI2. Finally, PCI2 was used for inoculation of tomato seeds to study its potential biocontrol activity against Fusarium oxysporum MR193. The obtained results showed that no fragments for the encoding genes of hydrogen cyanide, pyoluteorin, 2,4-diacetylphloroglucinol, pyrrolnitrin, or phenazine-1-carboxylic acid were amplified from the DNA of PCI2. On the other hand, PCI2 produced salicylic acid and jasmonic acid in Luria-Bertani medium and grew in a culture medium containing ACC as the sole nitrogen source. We observed a reduction in disease incidence from 53.33 % in the pathogen control to 30 % in tomato plants pre-inoculated with PCI2 as well as increases in shoot and root dry weights in inoculated plants, as compared to the pathogenicity control. This study suggests that inoculation of tomato seeds with P. putida PCI2 increases the resistance of plants to root rot caused by F. oxysporum and that PCI2 produces compounds that may be involved at different levels in increasing such resistance. Thus, PCI2 could represent a non-contaminating management strategy potentially applicable in vegetable crops such as tomato.

  11. Seroepidemiologic Survey of Potential Pathogens in Obligate and Facultative Scavenging Avian Species in California.

    PubMed

    Straub, Mary H; Kelly, Terra R; Rideout, Bruce A; Eng, Curtis; Wynne, Janna; Braun, Josephine; Johnson, Christine K

    2015-01-01

    Throughout the world, populations of scavenger birds are declining rapidly with some populations already on the brink of extinction. Much of the current research into the factors contributing to these declines has focused on exposure to drug residues, lead, and other toxins. Despite increased monitoring of these declining populations, little is known about infectious diseases affecting scavenger bird species. To assess potential infectious disease risks to both obligate and facultative scavenger bird species, we performed a serosurvey for eleven potential pathogens in three species of scavenging birds in California: the California condor (Gymnogyps californianus), turkey vulture (Cathartes aura) and golden eagle (Aquila chrysaetos). California condors were seropositive for avian adenovirus, infectious bronchitis virus, Mycoplasma gallisepticum, avian paramyxovirus-2, West Nile virus (WNV) and Toxoplasma gondii. Golden eagles were seropositive for avian adenovirus, Chlamydophila psittaci and Toxoplasma gondii, and turkey vultures were seropositive for avian adenovirus, Chlamydophila psittaci, avian paramyxovirus-1, Toxoplasma gondii and WNV. Risk factor analyses indicated that rearing site and original release location were significantly associated with a positive serologic titer to WNV among free-flying condors. This study provides preliminary baseline data on infectious disease exposure in these populations for aiding in early disease detection and provides potentially critical information for conservation of the endangered California condor as it continues to expand its range and encounter new infectious disease threats.

  12. Survival of Potentially Pathogenic Human-Associated Bacteria in the Rhizosphere of Hydroponically Grown Wheat

    NASA Technical Reports Server (NTRS)

    Morales, Anabelle; Garland, Jay L.; Lim, Daniel V.

    1996-01-01

    Plants may serve as reservoirs for human-associated bacteria (H-AB) in long-term space missions containing bioregenerative life support systems. The current study examined the abilities of five human-associated potential pathogens, Pseudomonas aeruginosa, Pseudomonas cepacia, Staphylococcus aureus, Streptococcus pyogenes, and Escherichia coli, to colonize and grow in the rhizosphere of hydroponically grown wheat, a candidate crop for life support. All of these bacteria have been recovered from past NASA missions and present potential problems for future missions. The abilities of these organisms to adhere to the roots of axenic five-day-old wheat (Triticum aestivum L. cv. Yecora rojo) were evaluated by enumeration of the attached organisms after a one hour incubation of roots in a suspension (approximately 10(exp 8 cu/ml)) of the H-AB. Results showed that a greater percentage of P. aeruginosa cells adhered to the wheat roots than the other four H-AB. Similarly incubated seedlings were also grown under attempted axenic conditions for seven days to examine the potential of each organism to proliferate in the rhizosphere (root colonization capacity). P. cepacia and P. aeruginosa showed considerable growth. E. coli and S. aureus showed no significant growth, and S. pyogenes died off in the wheat rhizosphere. Studies examining the effects of competition on the survival of these microorganisms indicated that P. aeruginosa was the only organism that survived in the rhizosphere of hydroponically grown wheat in the presence of different levels of microbial competition.

  13. Seroepidemiologic Survey of Potential Pathogens in Obligate and Facultative Scavenging Avian Species in California

    PubMed Central

    Straub, Mary H.; Kelly, Terra R.; Rideout, Bruce A.; Eng, Curtis; Wynne, Janna; Braun, Josephine; Johnson, Christine K.

    2015-01-01

    Throughout the world, populations of scavenger birds are declining rapidly with some populations already on the brink of extinction. Much of the current research into the factors contributing to these declines has focused on exposure to drug residues, lead, and other toxins. Despite increased monitoring of these declining populations, little is known about infectious diseases affecting scavenger bird species. To assess potential infectious disease risks to both obligate and facultative scavenger bird species, we performed a serosurvey for eleven potential pathogens in three species of scavenging birds in California: the California condor (Gymnogyps californianus), turkey vulture (Cathartes aura) and golden eagle (Aquila chrysaetos). California condors were seropositive for avian adenovirus, infectious bronchitis virus, Mycoplasma gallisepticum, avian paramyxovirus-2, West Nile virus (WNV) and Toxoplasma gondii. Golden eagles were seropositive for avian adenovirus, Chlamydophila psittaci and Toxoplasma gondii, and turkey vultures were seropositive for avian adenovirus, Chlamydophila psittaci, avian paramyxovirus-1, Toxoplasma gondii and WNV. Risk factor analyses indicated that rearing site and original release location were significantly associated with a positive serologic titer to WNV among free-flying condors. This study provides preliminary baseline data on infectious disease exposure in these populations for aiding in early disease detection and provides potentially critical information for conservation of the endangered California condor as it continues to expand its range and encounter new infectious disease threats. PMID:26606755

  14. Present-day potentialities of endoscopic diagnostics and treatment of early cancer in respiratory and digestive tracts

    NASA Astrophysics Data System (ADS)

    Sokolov, Victor V.; Zharkova, Natalia N.; Filonenko, E. V.; Telegina, L. V.; Karpova, E. S.

    1999-12-01

    The paper presents the latest potentialities of the endoscopic fluorescent diagnostics as well as endoscopic electric-, laser surgery and photodynamic therapy (PDT) of the early cancer in the respiratory and digestive tracts. We present in detail indication and factors determining the application of the endoscopic resection of the tumor. The advantages of the combination application of PDT, electro-, Nd:YAG laser surgery and brachitherapy are stressed. The near and remote results of endoscopic treatment of the early cancer in larynx (37), lung (109), esophagus (39) and stomach (58) are shown.

  15. Persistence and Potential Viable but Non-culturable State of Pathogenic Bacteria during Storage of Digestates from Agricultural Biogas Plants

    PubMed Central

    Maynaud, Geraldine; Pourcher, Anne-Marie; Ziebal, Christine; Cuny, Anais; Druilhe, Céline; Steyer, Jean-Philippe; Wéry, Nathalie

    2016-01-01

    Despite the development of on-farm anaerobic digestion as a process for making profitable use of animal by-products, factors leading to the inactivation of pathogenic bacteria during storage of digestates remain poorly described. Here, a microcosm approach was used to evaluate the persistence of three pathogenic bacteria (Salmonella enterica Derby, Campylobacter coli and Listeria monocytogenes) in digestates from farms, stored for later land spreading. Nine samples, including raw digestates, liquid fractions of digestate and composted digestates, were inoculated with each pathogen and maintained for 40 days at 24°C. Concentrations of pathogens were monitored using culture and qPCR methods. The persistence of L. monocytogenes, detected up to 20 days after inoculation, was higher than that of Salmonella Derby, detected for 7–20 days, and of C. coli (not detected after 7 days). In some digestates, the concentration of the pathogens by qPCR assay was several orders of magnitude higher than the concentration of culturable cells, suggesting a potential loss of culturability and induction of Viable but Non-Culturable (VBNC) state. The potential VBNC state which was generally not observed in the same digestate for the three pathogens, occurred more frequently for C. coli and L. monocytogenes than for Salmonella Derby. Composting a digestate reduced the persistence of seeded L. monocytogenes but promoted the maintenance of Salmonella Derby. The effect of NH4+/NH3 on the culturability of C. coli and Salmonella Derby was also shown. The loss of culturability may be the underlying mechanism for the regrowth of pathogens. We have also demonstrated the importance of using molecular tools to monitor pathogens in environmental samples since culture methods may underestimate cell concentration. Our results underline the importance of considering VBNC cells when evaluating the sanitary effect of an anaerobic digestion process and the persistence of pathogens during the storage of

  16. Respiratory symptoms among glass bottle makers exposed to stannic chloride solution and other potentially hazardous substances

    SciTech Connect

    Levy, B.S.; Davis, F.; Johnson, B.

    1985-04-01

    Concern about upper respiratory tract irritation and other symptoms among workers at a glass bottle manufacturing plant led to an epidemiologic and an industrial hygiene survey. Questionnaire responses from 35 hot end and 53 cold end workers indicated that the incidence of wheezing, chest pain, dyspnea on exertion, and cough was significantly elevated among hot end workers. Among both smokers and nonsmokers, hot end workers reported higher, but not significantly higher, rates of wheezing and chest pain. Among smokers, hot end workers reported significantly higher rates of dyspnea on exertion and cough than did cold end workers. Data suggest that reported exposure to stannic chloride solution likely caused these symptoms. The industrial hygiene survey, conducted when stannic chloride use had been reduced, cleaning had been done, and ventilation improved, focused on measuring air contaminants that might possibly cause symptoms. Levels of hydrogen chloride, which apparently was formed by the combination of stannic chloride and water in the presence of heat, were elevated. The finding of increased prevalence of respiratory symptoms among hot end workers was consistent with this exposure. Recommendations were made to reduce hazardous exposures at this plant. Individuals responsible for occupational health should be aware that relatively benign substances, such as stannic chloride and water, can combine spontaneously to form hazardous substances.

  17. Molecular characterization by amplified ribosomal DNA restriction analysis and antimicrobial potential of endophytic fungi isolated from Luehea divaricata (Malvaceae) against plant pathogenic fungi and pathogenic bacteria.

    PubMed

    Bernardi-Wenzel, J; Garcia, A; Azevedo, J L; Pamphile, J A

    2013-10-29

    Luehea divaricata is an important plant in popular medicine; it is used for its depurative, anti-inflammatory, and other therapeutic activities. We evaluated the antimicrobial activity of endophytic fungi isolated from leaves of L. divaricata against phytopathogens and pathogenic bacteria, and characterized the isolates based on amplified ribosomal DNA restriction analysis (ARDRA). The in vitro antagonistic activity of these endophytes against the phytopathogen Alternaria alternata was assayed by dual culture technique. Based on this evaluation of antimicrobial activity, we extracted secondary metabolites from nine endophytic fungi by partitioning in ethyl acetate and methanol. These were tested against the phytopathogens A. alternata, Colletotrichum sp and Moniliophthora perniciosa, and against the human pathogenic bacteria Escherichia coli and Staphylococcus aureus. Molecular characterization by ARDRA technique was used for phylogenetic analysis, based on comparison with sequences in GenBank. The endophytes had varied effects on A. alternata. One isolate produced an inhibition halo against M. perniciosa and against E. coli. This antibiosis activity indicates a role in the protection of the plant against microbial pathogens in nature, with potential for pharmaceutical and agricultural applications. Based on ARDRA, the 13 isolates were grouped. We found three different haplotypes of Phomopsis sp, showing interspecific variability. It appears that examination of the microbial community associated with medicinal plants of tropical regions has potential as a useful strategy to look for species with biotechnological applications.

  18. Composition and pathogenic potential of a microbial bioremediation product used for crude oil degradation.

    PubMed

    Tayabali, Azam F; Coleman, Gordon; Crosthwait, Jennifer; Nguyen, Kathy C; Zhang, Yan; Shwed, Philip

    2017-01-01

    A microbial bioremediation product (MBP) used for large-scale oil degradation was investigated for microbial constituents and possible pathogenicity. Aerobic growth on various media yielded >108 colonies mL-1. Full-length 16S rDNA sequencing and fatty acid profiling from morphologically distinct colonies revealed ≥13 distinct genera. Full-length 16S rDNA library sequencing, by either Sanger or long-read PacBio technology, suggested that up to 21% of the MBP was composed of Arcobacter. Other high abundance microbial constituents (>6%) included the genera Proteus, Enterococcus, Dysgonomonas and several genera in the order Bacteroidales. The MBP was most susceptible to ciprofloxacin, doxycycline, gentamicin, and meropenam. MBP exposure of human HT29 and A549 cells caused significant cytotoxicity, and bacterial growth and adherence. An acellular MBP filtrate was also cytotoxic to HT29, but not A549. Both MBP and filtrate exposures elevated the neutrophil chemoattractant IL-8. In endotracheal murine exposures, bacterial pulmonary clearance was complete after one-week. Elevation of pro-inflammatory cytokines IL-1β, IL-6, and TNF-α, and chemokines KC and MCP-1 occurred between 2h and 48h post-exposure, followed by restoration to baseline levels at 96h. Cytokine/chemokine signalling was accompanied by elevated blood neutrophils and monocytes at 4h and 48h, respectively. Peripheral acute phase response markers were maximal at 24h. All indicators examined returned to baseline values by 168h. In contrast to HT29, but similar to A549 observations, MBP filtrate did not induce significant murine effects with the indicators examined. The results demonstrated the potentially complex nature of MBPs and transient immunological effects during exposure. Products containing microbes should be scrutinized for pathogenic components and subjected to characterisation and quality validation prior to commercial release.

  19. "Features of two proteins of Leptospira interrogans with potential role in host-pathogen interactions"

    PubMed Central

    2012-01-01

    Background Leptospirosis is considered a re-emerging infectious disease caused by pathogenic spirochaetes of the genus Leptospira. Pathogenic leptospires have the ability to survive and disseminate to multiple organs after penetrating the host. Leptospires were shown to express surface proteins that interact with the extracellular matrix (ECM) and to plasminogen (PLG). This study examined the interaction of two putative leptospiral proteins with laminin, collagen Type I, collagen Type IV, cellular fibronectin, plasma fibronectin, PLG, factor H and C4bp. Results We show that two leptospiral proteins encoded by LIC11834 and LIC12253 genes interact with laminin in a dose - dependent and saturable mode, with dissociation equilibrium constants (KD) of 367.5 and 415.4 nM, respectively. These proteins were named Lsa33 and Lsa25 (Leptospiral surface adhesin) for LIC11834 and LIC12253, respectively. Metaperiodate - treated laminin reduced Lsa25 - laminin interaction, suggesting that sugar moieties of this ligand participate in this interaction. The Lsa33 is also PLG - binding receptor, with a KD of 23.53 nM, capable of generating plasmin in the presence of an activator. Although in a weak manner, both proteins interact with C4bp, a regulator of complement classical route. In silico analysis together with proteinase K and immunoflorescence data suggest that these proteins might be surface exposed. Moreover, the recombinant proteins partially inhibited leptospiral adherence to immobilized laminin and PLG. Conclusions We believe that these multifunctional proteins have the potential to participate in the interaction of leptospires to hosts by mediating adhesion and by helping the bacteria to escape the immune system and to overcome tissue barriers. To our knowledge, Lsa33 is the first leptospiral protein described to date with the capability of binding laminin, PLG and C4bp in vitro. PMID:22463075

  20. Composition and pathogenic potential of a microbial bioremediation product used for crude oil degradation

    PubMed Central

    Tayabali, Azam F.; Coleman, Gordon; Crosthwait, Jennifer; Nguyen, Kathy C.; Zhang, Yan; Shwed, Philip

    2017-01-01

    A microbial bioremediation product (MBP) used for large-scale oil degradation was investigated for microbial constituents and possible pathogenicity. Aerobic growth on various media yielded >108 colonies mL-1. Full-length 16S rDNA sequencing and fatty acid profiling from morphologically distinct colonies revealed ≥13 distinct genera. Full-length 16S rDNA library sequencing, by either Sanger or long-read PacBio technology, suggested that up to 21% of the MBP was composed of Arcobacter. Other high abundance microbial constituents (>6%) included the genera Proteus, Enterococcus, Dysgonomonas and several genera in the order Bacteroidales. The MBP was most susceptible to ciprofloxacin, doxycycline, gentamicin, and meropenam. MBP exposure of human HT29 and A549 cells caused significant cytotoxicity, and bacterial growth and adherence. An acellular MBP filtrate was also cytotoxic to HT29, but not A549. Both MBP and filtrate exposures elevated the neutrophil chemoattractant IL-8. In endotracheal murine exposures, bacterial pulmonary clearance was complete after one-week. Elevation of pro-inflammatory cytokines IL-1β, IL-6, and TNF-α, and chemokines KC and MCP-1 occurred between 2h and 48h post-exposure, followed by restoration to baseline levels at 96h. Cytokine/chemokine signalling was accompanied by elevated blood neutrophils and monocytes at 4h and 48h, respectively. Peripheral acute phase response markers were maximal at 24h. All indicators examined returned to baseline values by 168h. In contrast to HT29, but similar to A549 observations, MBP filtrate did not induce significant murine effects with the indicators examined. The results demonstrated the potentially complex nature of MBPs and transient immunological effects during exposure. Products containing microbes should be scrutinized for pathogenic components and subjected to characterisation and quality validation prior to commercial release. PMID:28178315

  1. Potential oversummering and overwintering regions for the wheat stripe rust pathogen in the contiguous United States

    NASA Astrophysics Data System (ADS)

    Sharma-Poudyal, Dipak; Chen, Xianming; Rupp, Richard Alan

    2014-07-01

    Epidemics of wheat stripe rust, caused by Puccinia striiformis f. sp. tritici ( Pst), are more frequent in the regions where Pst can oversummer and overwinter. Regions for potential oversummering and overwintering of Pst were determined in the contiguous United States using a survival index (SI) ranging from 0 (most unfavorable) to 10 (most favorable) developed based on long-term weather data. The pathogen can survive in cool summer in the most regions north of latitude 40°N, particularly Washington, Idaho, Montana, Oregon and California. Due to limiting high temperatures, it survives marginally during summer in Arkansas, Delaware, Georgia, Iowa, Illinois, Indiana, Kansas, Kentucky, Massachusetts, Missouri, Ohio, Oklahoma, Rhode Island and Texas. Similarly, unfavorable hot summer restricts summer survival of the pathogen in the most regions south of 40°N except for highlands in the Rocky or Appalachian Mountains. Warm winters favor fungal survival in most regions south of 40°N and the Pacific Coast, including Alabama, Arkansas, Arizona, California, Florida, Georgia, Idaho, Louisiana, Mississippi, New Mexico, Nevada, Oregon, South Carolina, Texas and Washington. Severe winters do not allow survival in most regions north of 40°N and east of the Rocky Mountains, whereas less severe winter in Delaware, Illinois, Indiana, Kansas, Kentucky, Massachusetts, Maryland, Michigan, Missouri, North Carolina, New Jersey, New York, Ohio, Oklahoma, Pennsylvania, Rhode Island, Tennessee, Utah and Virginia permits marginal survival of Pst. Most wheat-growing regions have climatic suitability for either oversummering or overwintering. Both oversummering and overwintering can occur in the Pacific Northwest (Idaho, Oregon and Washington), Arizona, California, North Carolina, New Mexico, Pennsylvania, Virginia and West Virginia. These regions may provide primary inoculum for stripe rust epidemics in their own and surrounding regions.

  2. Invertebrate pathogenicity and toxin-producing potential of strains of Bacillus thuringiensis endemic to Antarctica.

    PubMed

    Prabhakar, A; Bishop, A H

    2011-06-01

    Several strains of Bacillus thuringiensis were previously isolated from soil in Antarctica and appeared to have physiological adaptations to this cold, nutrient-poor environment. In spite of this they could produce abnormally large, parasporal crystals under laboratory conditions. Here, they have been further characterised for toxin genes and invertebrate pathogenicity. All of the strains were positive in PCR assays for the cry1Aa and cry2 genes. This was confirmed by sequence analysis and the parasporal crystals of all strains contained polypeptides of about 130kDa. This potential for lepidopteran toxicity was borne out in bioassays of purified δ-endotoxins against larvae of Pieris brassicae: the LD(50) values of B2408 (288μg) were comparable to that of the reference strain, HD-12 (201μg). There was no activity against the nematode Caenorhabditis elegans in spite of the fact that all strains appeared to possess the cry6 gene. PCR screening for genes encoding other nematode-toxic classes of toxins (Cry5, 4 and 21) was negative. B. thuringiensis has never previously been shown to be toxic to Collembola (springtails) but the purified δ-endotoxins of one of the Antarctic strains showed some activity against Folsomia candida and Seira domestica (224μg and 238μg, respectively). It seems unlikely that the level of toxicity demonstrated against springtails would support a pathogenic life-style in nature. All of the strains were positive for genes encoding Bacillus cereus-type enterotoxins. In the absence of higher insects and mammals the ecological value of retaining the toxic capability demonstrated here is uncertain.

  3. Protective or pathogenic effects of vascular endothelial growth factor (VEGF) as potential biomarker in cerebral malaria

    PubMed Central

    Canavese, Miriam; Spaccapelo, Roberta

    2014-01-01

    Cerebral malaria (CM) is the major lethal complication of Plasmodium falciparum infection. It is characterized by persistent coma along with symmetrical motor signs. Several clinical, histopathological, and laboratory studies have suggested that cytoadherence of parasitized erythrocytes, neural injury by malarial toxin, and excessive inflammatory cytokine production are possible pathogenic mechanisms. Although the detailed pathophysiology of CM remains unsolved, it is thought that the binding of parasitized erythrocytes to the cerebral endothelia of microvessels, leading to their occlusion and the consequent angiogenic dysregulation play a key role in the disease pathogenesis. Recent evidences showed that vascular endothelial growth factor (VEGF) and its receptor-related molecules are over-expressed in the brain tissues of CM patients, as well as increased levels of VEGF are detectable in biologic samples from malaria patients. Whether the modulation of VEGF is causative agent of CM mortality or a specific phenotype of patients with susceptibility to fatal CM needs further evaluation. Currently, there is no biological test available to confirm the diagnosis of CM and its complications. It is hoped that development of biomarkers to identify patients and potential risk for adverse outcomes would greatly enhance better intervention and clinical management to improve the outcomes. We review and discuss here what it is currently known in regard to the role of VEGF in CM as well as VEGF as a potential biomarker. PMID:24601908

  4. Systems Integration of Biodefense Omics Data for Analysis of Pathogen-Host Interactions and Identification of Potential Targets

    PubMed Central

    McGarvey, Peter B.; Huang, Hongzhan; Mazumder, Raja; Zhang, Jian; Chen, Yongxing; Zhang, Chengdong; Cammer, Stephen; Will, Rebecca; Odle, Margie; Sobral, Bruno; Moore, Margaret; Wu, Cathy H.

    2009-01-01

    The NIAID (National Institute for Allergy and Infectious Diseases) Biodefense Proteomics program aims to identify targets for potential vaccines, therapeutics, and diagnostics for agents of concern in bioterrorism, including bacterial, parasitic, and viral pathogens. The program includes seven Proteomics Research Centers, generating diverse types of pathogen-host data, including mass spectrometry, microarray transcriptional profiles, protein interactions, protein structures and biological reagents. The Biodefense Resource Center (www.proteomicsresource.org) has developed a bioinformatics framework, employing a protein-centric approach to integrate and support mining and analysis of the large and heterogeneous data. Underlying this approach is a data warehouse with comprehensive protein + gene identifier and name mappings and annotations extracted from over 100 molecular databases. Value-added annotations are provided for key proteins from experimental findings using controlled vocabulary. The availability of pathogen and host omics data in an integrated framework allows global analysis of the data and comparisons across different experiments and organisms, as illustrated in several case studies presented here. (1) The identification of a hypothetical protein with differential gene and protein expressions in two host systems (mouse macrophage and human HeLa cells) infected by different bacterial (Bacillus anthracis and Salmonella typhimurium) and viral (orthopox) pathogens suggesting that this protein can be prioritized for additional analysis and functional characterization. (2) The analysis of a vaccinia-human protein interaction network supplemented with protein accumulation levels led to the identification of human Keratin, type II cytoskeletal 4 protein as a potential therapeutic target. (3) Comparison of complete genomes from pathogenic variants coupled with experimental information on complete proteomes allowed the identification and prioritization of ten

  5. The CRP/FNR family protein Bcam1349 is a c-di-GMP effector that regulates biofilm formation in the respiratory pathogen Burkholderia cenocepacia.

    PubMed

    Fazli, Mustafa; O'Connell, Aileen; Nilsson, Martin; Niehaus, Karsten; Dow, J Maxwell; Givskov, Michael; Ryan, Robert P; Tolker-Nielsen, Tim

    2011-10-01

    Burkholderia cenocepacia is an opportunistic respiratory pathogen that can cause severe infections in immune-compromised individuals and is associated with poor prognosis for patients suffering from cystic fibrosis. The second messenger cyclic diguanosine monophosphate (c-di-GMP) has been shown to control a wide range of functions in bacteria, but little is known about these regulatory mechanisms in B. cenocepacia. Here we investigated the role that c-di-GMP plays in the regulation of biofilm formation and virulence in B. cenocepacia. Elevated intracellular levels of c-di-GMP promoted wrinkly colony, pellicle and biofilm formation in B. cenocepacia. A screen for transposon mutants unable to respond to elevated levels of c-di-GMP led to the identification of the mutant bcam1349 that did not display increased biofilm and pellicle formation with excessive c-di-GMP levels, and displayed a biofilm defect with physiological c-di-GMP levels. The bcam1349 gene is predicted to encode a transcriptional regulator of the CRP/FNR superfamily. Analyses of purified Bcam1349 protein and truncations demonstrated that it binds c-di-GMP in vitro. The Bcam1349 protein was shown to regulate the production of a number of components, including cellulose and fimbriae. It was demonstrated that the Bcam1349 protein binds to the promoter region of the cellulose synthase genes, and that this binding is enhanced by the presence of c-di-GMP. The bcam1349 mutant showed reduced virulence in a Galleria mellonella wax moth larvae infection model. Taken together, these findings suggest that the Bcam1349 protein is a transcriptional regulator that binds c-di-GMP and regulates biofilm formation and virulence in B. cenocepacia in response to the level of c-di-GMP.

  6. Antibacterial activity and mechanism of action of Monarda punctata essential oil and its main components against common bacterial pathogens in respiratory tract.

    PubMed

    Li, Hong; Yang, Tian; Li, Fei-Yan; Yao, Yan; Sun, Zhong-Min

    2014-01-01

    The aim of the current research work was to study the chemical composition of the essential oil of Monarda punctata along with evaluating the essential oil and its major components for their antibacterial effects against some frequently encountered respiratory infection causing pathogens. Gas chromatographic mass spectrometric analysis revealed the presence of 13 chemical constituents with thymol (75.2%), p-cymene (6.7%), limonene (5.4), and carvacrol (3.5%) as the major constituents. The oil composition was dominated by the oxygenated monoterpenes. Antibacterial activity of the essential oil and its major constituents (thymol, p-cymene, limonene) was evaluated against Streptococcus pyogenes, methicillin-resistant Staphylococcus aureus (MRSA), Streptococcus pneumoniae, Haemophilus influenzae and Escherichia coli. The study revealed that the essential oil and its constituents exhibited a broad spectrum and variable degree of antibacterial activity against different strains. Among the tested strains, Streptococcus pyogenes, Escherichia coli and Streptococcus pneumoniae were the most susceptible bacterial strain showing lowest MIC and MBC values. Methicillin-resistant Staphylococcus aureus was the most resistant bacterial strain to the essential oil treatment showing relatively higher MIC and MBC values. Scanning electron microscopy revealed that the essential oil induced potent and dose-dependent membrane damage in S. pyogenes and MRSA bacterial strains. The reactive oxygen species generated by the Monarda punctata essential oil were identified using 2', 7'-dichlorofluorescein diacetate (DCFDA).This study indicated that the Monarda punctata essential oil to a great extent and thymol to a lower extent triggered a substantial increase in the ROS levels in S. pyogenes bacterial cultures which ultimately cause membrane damage as revealed by SEM results.

  7. Antibacterial activity and mode of action of the Artemisia capillaris essential oil and its constituents against respiratory tract infection-causing pathogens.

    PubMed

    Yang, Chang; Hu, Dong-Hui; Feng, Yan

    2015-04-01

    Inhalation therapy using essential oils has been used to treat acute and chronic sinusitis and bronchitis. The aim of the present study was to determine the chemical composition of the essential oil of Artemisia capillaris, and evaluate the antibacterial effects of the essential oil and its main components, against common clinically relevant respiratory bacterial pathogens. Gas chromatography and gas chromatography‑mass spectrometry revealed the presence of 25 chemical constituents, the main constituents being: α‑pinene, β‑pinene, limonene, 1,8‑cineole, piperitone, β‑caryophyllene and capillin. The antibacterial activities of the essential oil, and its major constituents, were evaluated against Streptococcus pyogenes, methicillin‑resistant Staphylococcus aureus (MRSA), MRSA (clinical strain), methicillin‑gentamicin resistant Staphylococcus aureus (MGRSA), Streptococcus pneumoniae, Klebsiella pneumoniae, Haemophilus influenzae and Escherichia coli. The essential oil and its constituents exhibited a broad spectrum and variable degree of antibacterial activity against the various strains. The essential oil was observed to be much more potent, as compared with any of its major chemical constituents, exhibiting low minimum inhibitory and bacteriocidal concentration values against all of the bacterial strains. The essential oil was most active against S. pyogenes, MRSA (clinical strain), S. pneumoniae, K. pneumoniae, H. influenzae and E. coli. Piperitone and capillin were the most potent growth inhibitors, among the major chemical constituents. Furthermore, the essential oil of A. capillaris induced significant and dose‑dependent morphological changes in the S. aureus bacterial strain, killing >90% of the bacteria when administered at a higher dose; as determined by scanning electron microscopy. In addition, the essential oil induced a significant leakage of potassium and phosphate ions from the S. aureus bacterial cultures. These results indicate that

  8. Assessing pathogenicity of Gallibacterium anatis in a natural infection model: the respiratory and reproductive tracts of chickens are targets for bacterial colonization.

    PubMed

    Paudel, Surya; Alispahic, Merima; Liebhart, Dieter; Hess, Michael; Hess, Claudia

    2013-12-01

    Two separate bird trials were performed to establish a reliable route of infection for Gallibacterium anatis in chickens, comparing intranasal (i.n.) and intravenous (i.v.) applications. Additionally, three mutually divergent isolates from three geographical locations, as shown by MALDI-TOF-MS and partial rpoB gene sequence analysis, were compared. In the first trial, birds were infected with one of the selected isolates by the i.v. or i.n. route. Subsequently, birds were killed 3, 12 and 24 h post infection following i.v. infection while at 3, 7 and 10 days post infection (dpi) in the case of i.n. infection along with birds of the control group. As a result, i.n. infection showed prominent and consistent bacterial tissue distribution in different organs persisting until 10 dpi, which was a striking contrast to the i.v. infection route. Likewise, histopathology revealed mild to severe tracheal lesions following i.n. infection. The second trial was set up to confirm both the achieved results and the robustness of i.n. infection but with an extended observation period, until 28 dpi In agreement with the preceding trial, identical results for bacteriological and histopathological examinations were obtained with persistency of bacteria until 28 dpi Comparing the three different isolates from Mexico, China and Austria, the Mexican isolate showed a somewhat higher pathogenicity than the other strains. Consequently, pathogenesis of G. anatis strains was studied in chickens elucidating i.n. infection as the most reliable route characterized by a long-lasting bacteraemia, targeting the respiratory and reproductive tract.

  9. Antibacterial activity and mechanism of action of Monarda punctata essential oil and its main components against common bacterial pathogens in respiratory tract

    PubMed Central

    Li, Hong; Yang, Tian; Li, Fei-Yan; Yao, Yan; Sun, Zhong-Min

    2014-01-01

    The aim of the current research work was to study the chemical composition of the essential oil of Monarda punctata along with evaluating the essential oil and its major components for their antibacterial effects against some frequently encountered respiratory infection causing pathogens. Gas chromatographic mass spectrometric analysis revealed the presence of 13 chemical constituents with thymol (75.2%), p-cymene (6.7%), limonene (5.4), and carvacrol (3.5%) as the major constituents. The oil composition was dominated by the oxygenated monoterpenes. Antibacterial activity of the essential oil and its major constituents (thymol, p-cymene, limonene) was evaluated against Streptococcus pyogenes, methicillin-resistant Staphylococcus aureus (MRSA), Streptococcus pneumoniae, Haemophilus influenzae and Escherichia coli. The study revealed that the essential oil and its constituents exhibited a broad spectrum and variable degree of antibacterial activity against different strains. Among the tested strains, Streptococcus pyogenes, Escherichia coli and Streptococcus pneumoniae were the most susceptible bacterial strain showing lowest MIC and MBC values. Methicillin-resistant Staphylococcus aureus was the most resistant bacterial strain to the essential oil treatment showing relatively higher MIC and MBC values. Scanning electron microscopy revealed that the essential oil induced potent and dose-dependent membrane damage in S. pyogenes and MRSA bacterial strains. The reactive oxygen species generated by the Monarda punctata essential oil were identified using 2’, 7’-dichlorofluorescein diacetate (DCFDA).This study indicated that the Monarda punctata essential oil to a great extent and thymol to a lower extent triggered a substantial increase in the ROS levels in S. pyogenes bacterial cultures which ultimately cause membrane damage as revealed by SEM results. PMID:25550774

  10. The microbiota of the respiratory tract: gatekeeper to respiratory health.

    PubMed

    Man, Wing Ho; de Steenhuijsen Piters, Wouter A A; Bogaert, Debby

    2017-03-20

    The respiratory tract is a complex organ system that is responsible for the exchange of oxygen and carbon dioxide. The human respiratory tract spans from the nostrils to the lung alveoli and is inhabited by niche-specific communities of bacteria. The microbiota of the respiratory tract probably acts as a gatekeeper that provides resistance to colonization by respiratory pathogens. The respiratory microbiota might also be involved in the maturation and maintenance of homeostasis of respiratory physiology and immunity. The ecological and environmental factors that direct the development of microbial communities in the respiratory tract and how these communities affect respiratory health are the focus of current research. Concurrently, the functions of the microbiome of the upper and lower respiratory tract in the physiology of the human host are being studied in detail. In this Review, we will discuss the epidemiological, biological and functional evidence that support the physiological role of the respiratory microbiota in the maintenance of human health.

  11. Cronobacter sakazakii: stress survival and virulence potential in an opportunistic foodborne pathogen.

    PubMed

    Feeney, Audrey; Kropp, Kai A; O'Connor, Roxana; Sleator, Roy D

    2014-01-01

    A characteristic feature of the opportunistic foodborne pathogen Cronobacter sakazakii is its ability to survive in extremely arid environments, such as powdered infant formula, making it a dangerous opportunistic pathogen of individuals of all age groups, especially infants and neonates. Herein, we provide a brief overview of the pathogen; clinical manifestations, environmental reservoirs and our current understanding of stress response mechanisms and virulence factors which allow it to cause disease.

  12. Cronobacter sakazakii: stress survival and virulence potential in an opportunistic foodborne pathogen

    PubMed Central

    Feeney, Audrey; Kropp, Kai A; O’Connor, Roxana; Sleator, Roy D

    2014-01-01

    A characteristic feature of the opportunistic foodborne pathogen Cronobacter sakazakii is its ability to survive in extremely arid environments, such as powdered infant formula, making it a dangerous opportunistic pathogen of individuals of all age groups, especially infants and neonates. Herein, we provide a brief overview of the pathogen; clinical manifestations, environmental reservoirs and our current understanding of stress response mechanisms and virulence factors which allow it to cause disease. PMID:25562731

  13. Aeromonas hydrophila and Aeromonas veronii Predominate among Potentially Pathogenic Ciprofloxacin- and Tetracycline-Resistant Aeromonas Isolates from Lake Erie

    PubMed Central

    Shinko, Jasmine; Augustyniak, Alexander; Gee, Christopher; Andraso, Greg

    2014-01-01

    Members of the genus Aeromonas are ubiquitous in nature and have increasingly been implicated in numerous diseases of humans and other animal taxa. Although some species of aeromonads are human pathogens, their presence, density, and relative abundance are rarely considered in assessing water quality. The objectives of this study were to identify Aeromonas species within Lake Erie, determine their antibiotic resistance patterns, and assess their potential pathogenicity. Aeromonas strains were isolated from Lake Erie water by use of Aeromonas selective agar with and without tetracycline and ciprofloxacin. All isolates were analyzed for hemolytic ability and cytotoxicity against human epithelial cells and were identified to the species level by using 16S rRNA gene restriction fragment length polymorphisms and phylogenetic analysis based on gyrB gene sequences. A molecular virulence profile was identified for each isolate, using multiplex PCR analysis of six virulence genes. We demonstrated that Aeromonas comprised 16% of all culturable bacteria from Lake Erie. Among 119 Aeromonas isolates, six species were identified, though only two species (Aeromonas hydrophila and A. veronii) predominated among tetracycline- and ciprofloxacin-resistant isolates. Additionally, both of these species demonstrated pathogenic phenotypes in vitro. Virulence gene profiles demonstrated a high prevalence of aerolysin and serine protease genes among A. hydrophila and A. veronii isolates, a genetic profile which corresponded with pathogenic phenotypes. Together, our findings demonstrate increased antibiotic resistance among potentially pathogenic strains of aeromonads, illustrating an emerging potential health concern. PMID:24242249

  14. Oscillatory behavior of ventricular action potential duration in heart failure patients at respiratory rate and low frequency

    PubMed Central

    Hanson, Ben; Child, Nick; Van Duijvenboden, Stefan; Orini, Michele; Chen, Zhong; Coronel, Ruben; Rinaldi, Christopher A.; Gill, Jaspal S.; Gill, Jaswinder S.; Taggart, Peter

    2014-01-01

    Oscillations of arterial pressure occur spontaneously at a frequency of approximately 0.1 Hz coupled with synchronous oscillations of sympathetic nerve activity (“Mayer waves”). This study investigated the extent to which corresponding oscillations may occur in ventricular action potential duration (APD). Fourteen ambulatory (outpatient) heart failure patients with biventricular pacing devices were studied while seated upright watching movie clips to maintain arousal. Activation recovery intervals (ARI) as a measure of ventricular APD were obtained from unipolar electrograms recorded from the LV epicardial pacing lead during steady state RV pacing from the device. Arterial blood pressure was measured non-invasively (Finapress) and respiration monitored. Oscillations were quantified using time frequency and coherence analysis. Oscillatory behavior of ARI at the respiratory frequency was observed in all subjects. The magnitude of the ARI variation ranged from 2.2 to 6.9 ms (mean 5.0 ms). Coherence analysis showed a correlation with respiratory oscillation for an average of 43% of the recording time at a significance level of p < 0.05. Oscillations in systolic blood pressure in the Mayer wave frequency range were observed in all subjects for whom blood pressure was recorded (n = 13). ARI oscillation in the Mayer wave frequency range was observed in 6/13 subjects (46%) over a range of 2.9 to 9.2 ms. Coherence with Mayer waves at the p < 0.05 significance level was present for an average of 29% of the recording time. In ambulatory patients with heart failure during enhanced mental arousal, left ventricular epicardial APD (ARI) oscillated at the respiratory frequency (approximately 0.25 Hz). In 6 patients (46%) APD oscillated at the slower Mayer wave frequency (approximately 0.1 Hz). These findings may be important in understanding sympathetic activity-related arrhythmogenesis. PMID:25389408

  15. Functional analysis of a lipolytic protein, a potential phytoplasma pathogenicity factor

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wall-less bacteria known as phytoplasmas are obligate transkingdom parasites and pathogens of plants and insect vectors. These unusual bacteria possess some of the smallest genomes known among pathogenic bacteria, and have never been successfully isolated in artificial culture. Disease symptoms in...

  16. Genome sequence of Aureobasidium pullulans AY4, an emerging opportunistic fungal pathogen with diverse biotechnological potential.

    PubMed

    Chan, Giek Far; Bamadhaj, Hasima Mustafa; Gan, Han Ming; Rashid, Noor Aini Abdul

    2012-11-01

    Aureobasidium pullulans AY4 is an opportunistic pathogen that was isolated from the skin of an immunocompromised patient. We present here the draft genome of strain AY4, which reveals an abundance of genes relevant to bioindustrial applications, including biocontrol and biodegradation. Putative genes responsible for the pathogenicity of strain AY4 were also identified.

  17. Review of current methods for characterizing virulence and pathogenicity potential of industrial Saccharomyces cerevisiae strains towards humans.

    PubMed

    Anoop, Valar; Rotaru, Sever; Shwed, Philip S; Tayabali, Azam F; Arvanitakis, George

    2015-09-01

    Most industrial Saccharomyces cerevisiae strains used in food or biotechnology processes are benign. However, reports of S. cerevisiae infections have emerged and novel strains continue to be developed. In order to develop recommendations for the human health risk assessment of S. cerevisiae strains, we conducted a literature review of current methods used to characterize their pathogenic potential and evaluated their relevance towards risk assessment. These studies revealed that expression of virulence traits in S. cerevisiae is complex and depends on many factors. Given the opportunistic nature of this organism, an approach using multiple lines of evidence is likely necessary for the reasonable prediction of the pathogenic potential of a particular strain. Risk assessment of S. cerevisiae strains would benefit from more research towards the comparison of virulent and non-virulent strains in order to better understand those genotypic and phenotypic traits most likely to be associated with pathogenicity.

  18. Current and potential impacts of mosquitoes and the pathogens they vector in the Pacific region

    USGS Publications Warehouse

    LaPointe, Dennis

    2007-01-01

    Mosquitoes and the pathogens they transmit are ubiquitous throughout most of the temperate and tropical regions of the world. The natural and pre-European distribution and diversity of mosquitoes and mosquito-borne diseases throughout much of the Pacific region, however, depicts a depauperate and relatively benign fauna reinforcing the dream of “paradise regained”. In the central and South Pacific few mosquito species were able to colonize the remotest islands and atolls. Native mosquitoes are limited to a few far-ranging species and island endemics are typically restricted to the genera of Aedes and Culex. Only lymphatic filariasis appears to have been present as an endemic mosquito-borne disease before European contact. In nearby Australia, however, some 242 species of mosquitoes are known to occur and more than 70 arboviruses have been identified (Mackenzie 1999). In this regard Australia is more similar to the rest of the tropic and subtropical world than the smaller islands of Oceania. In our ever-shrinking world of global commerce, military activity and travel, the nature of mosquito-borne disease in the Pacific was bound to change. This paper is a brief summary of introduced mosquitoes in the Pacific and their potential impacts on human and wildlife health.

  19. Antibacterial potential of silver nanoparticles against isolated urinary tract infectious bacterial pathogens

    NASA Astrophysics Data System (ADS)

    Jacob Inbaneson, Samuel; Ravikumar, Sundaram; Manikandan, Nachiappan

    2011-12-01

    The silver nanoparticles were synthesized by chemical reduction method and the nanoparticles were characterized using ultraviolet-visible (UV-Vis) absorption spectroscopy and X-ray diffraction (XRD) studies. The synthesized silver nanoparticles were investigated to evaluate the antibacterial activity against urinary tract infectious (UTIs) bacterial pathogens. Thirty-two bacteria were isolated from mid urine samples of 25 male and 25 female patients from Thondi, Ramanathapuram District, Tamil Nadu, India and identified by conventional methods. Escherichia coli was predominant (47%) followed by Pseudomonas aeruginosa (22%), Klebsiella pneumoniae (19%), Enterobacter sp. (6%), Proteus morganii (3%) and Staphylococcus aureus (3%). The antibacterial activity of silver nanoparticles was evaluated by disc diffusion assay. P. aeruginosa showed maximum sensitivity (11 ± 0.58 mm) followed by Enterobacter sp. (8 ± 0.49 mm) at a concentration of 20 μg disc-1 and the sensitivity was highly comparable with the positive control kanamycin and tetracycline. K. pneumoniae, E. coli, P. morganii and S. aureus showed no sensitivity against all the tested concentrations of silver nanoparticles. The results provided evidence that, the silver nanoparticles might indeed be the potential sources to treat urinary tract infections caused by P. aeruginosa and Enterobacter sp.

  20. Chronic laminitis is associated with potential bacterial pathogens in the laminae.

    PubMed

    Onishi, Janet C; Park, Joong-Wook; Häggblom, Max M; Fennell, Michael J; Fugaro, Michael N

    2012-08-17

    A common sequella of chronic laminitis in horses is repeated abscesses with variable lameness and drainage. It is unclear whether the exudate represents the debridement phase of a non-septic inflammatory process involving clearance of laminar tissue damaged during the acute episode of laminitis, or a response to a microbial infection developed by ascent of microbes from the environment to the tissue via the white line. The objective of this study was to evaluate the possibility that an undiagnosed microbial infection in laminar tissue is present in laminar tissue collected from chronically laminitic horses without an active hoof abscess. Methods to collect laminar tissue, aseptically, from control (non-laminitic) horses and those with chronic/recurrent laminitis are described. Laminae homogenates were evaluated for the presence of bacteria. Bacteria were identified using biochemical tests and sequencing of 16S rRNA and virulence genes. Laminae from chronically laminitic horses revealed 100-fold higher levels (P=0.002) of bacteria compared to control, non-laminitic horses. Although environmental organisms were identified, potential pathogens were identified. Included were Gram positive bacteria, Brevibacterium luteolum, coagulase-negative Staphylococcus spp. as well as Gram negative bacteria, enterohemorrhagic Escherichia coli and Alcaligenes faecalis. Further research is warranted to evaluate the role of bacteria in equine chronic laminitis.

  1. Adaptive potential of ash (Fraxinus excelsior) populations against the novel emerging pathogen Hymenoscyphus pseudoalbidus

    PubMed Central

    Kjær, Erik Dahl; McKinney, Lea Vig; Nielsen, Lene Rostgaard; Hansen, Lars Nørgaard; Hansen, Jon Kehlet

    2012-01-01

    An emerging infectious pathogen Hymenoscyphus pseudoalbidus has spread across much of Europe within recent years causing devastating damage on European common ash trees (Fraxinus excelsior) and associated plant communities. The present study demonstrates the presence of additive genetic variation in susceptibility of natural F. excelsior populations to the new invasive disease. We observe high levels of additive variation in the degree of susceptibility with relatively low influence of environmental factors (narrow-sense heritability = 0.37–0.52). Most native trees are found to be highly susceptible, and we estimate that only around 1% has the potential of producing offspring with expected crown damage of <10% under the present disease pressure. The results suggest that the presence of additive genetic diversity in natural F. excelsior populations can confer the species with important ability to recover, but that low resistance within natural European populations is to be expected because of a low frequency of the hypo-sensitive trees. Large effective population sizes will be required to avoid genetic bottlenecks. The role of artificial selection and breeding for protection of the species is discussed based on the findings. PMID:25568043

  2. Antimicrobial potential of Ricinus communis leaf extracts in different solvents against pathogenic bacterial and fungal strains

    PubMed Central

    Naz, Rabia; Bano, Asghari

    2012-01-01

    Objective To investigate the in vitro antimicrobial activities of the leaf extract in different solvents viz., methanol, ethanol and water extracts of the selected plant Ricinus communis. Methods Agar well diffusion method and agar tube dilution method were carried out to perform the antibacterial and antifungal activity of methanol, ethanol and aqueous extracts. Results Methanol leaf extracts were found to be more active against Gram positive bacteria (Bacillus subtilis: ATCC 6059 and Staphylococcus aureus: ATCC 6538) as well as Gram negative bacteria (Pseudomonas aeruginosa: ATCC 7221 and Klebsiella pneumoniae) than ethanol and aqueous leaf extracts. Antifungal activity of methanol and aqueous leaf extracts were also carried out against selected fungal strains as Aspergillus fumigatus and Aspergillus flavus. Methanolic as well as aqueous leaf extracts of Ricinus communis were effective in inhibiting the fungal growth. Conclusions The efficient antibacterial and antifungal activity of Ricinus communis from the present investigation revealed that the methanol leaf extracts of the selected plant have significant potential to inhibit the growth of pathogenic bacterial and fungal strains than ethanol and aqueous leaf extracts. PMID:23593573

  3. Antimicrobial potential of Halophilic actinomycetes against multi drug resistant (MDR) ventilator associated pneumonia causing bacterial pathogens.

    PubMed

    Aslam, Sana; Sajid, Imran

    2016-03-01

    A collection of forty halophilic actinomycetes isolated from water and mud samples of the saline lake at Kalar Kahar, salt range, Pakistan, was screened to investigate their antimicrobial potential against multi drug resistant (MDR) ventilator associated pneumonia causing bacterial pathogens. The isolates exhibited significant tolerance to alkaline conditions and grew well at pH 9-11. The taxonomic status of the isolated strains was determined by morphological, biochemical and physiological characterization and by 16s rRNA gene sequencing. The results revealed that majority of the isolates (90%) belong to the genus Streptomyces. Most of the isolates exhibited remarkable antimicrobial activity up to 20mm zone of inhibition against MDR ventilator associated pneumonia causing bacteria including Staphylococcus aureus, Pseudomonas aeruginosa, Proteus vulgaris, Klebsiella pneumoniae, Escherichia coli, Enterobacter and Acinetobacter spp. Additionally the isolates showed moderate to high cytotoxicity in the range of 40 to 80% larval mortality against Artemia salina in a micro well cytotoxicity assay. The chemical screening or the so called metabolic fingerprinting of the methanolic extracts of each isolate, by thin layer chromatography (TLC) using various staining reagents and by high performance liquid chromatography (HPLC-UV), indicated an impressive diversity of the compounds produced by these strains. The study reveals that these halophilic actinomycetes are a promising source of bioactive compounds. The preparative scale fermentation, isolation, purification and structure elucidation of the compounds produced by them may yield novel antimicrobial or chemotherapeutic agents.

  4. Identification of Pathogenic Fusarium spp. Causing Maize Ear Rot and Potential Mycotoxin Production in China.

    PubMed

    Duan, Canxing; Qin, Zihui; Yang, Zhihuan; Li, Weixi; Sun, Suli; Zhu, Zhendong; Wang, Xiaoming

    2016-06-21

    Ear rot is a serious disease that affects maize yield and grain quality worldwide. The mycotoxins are often hazardous to humans and livestock. In samples collected in China between 2009 and 2014, Fusarium verticillioides and F. graminearum species complex were the dominant fungi causing ear rot. According to the TEF-1α gene sequence, F. graminearum species complex in China included three independent species: F. graminearum, F. meridionale, and F. boothii. The key gene FUM1 responsible for the biosynthesis of fumonisin was detected in all 82 F. verticillioides isolates. Among these, 57 isolates mainly produced fumonisin B₁, ranging from 2.52 to 18,416.44 µg/g for each gram of dry hyphal weight, in vitro. Three different toxigenic chemotypes were detected among 78 F. graminearum species complex: 15-ADON, NIV and 15-ADON+NIV. Sixty and 16 isolates represented the 15-ADON and NIV chemotypes, respectively; two isolates carried both 15-ADON and NIV-producing segments. All the isolates carrying NIV-specific segment were F. meridionale. The in vitro production of 15-ADON, 3-ADON, DON, and ZEN varied from 5.43 to 81,539.49; 6.04 to 19,590.61; 13.35 to 19,795.33; and 1.77 to 430.24 µg/g of dry hyphal weight, respectively. Altogether, our present data demonstrate potential main mycotoxin production of dominant pathogenic Fusarium in China.

  5. Prevalence of potentially pathogenic enteric organisms in clinically healthy kittens in the UK.

    PubMed

    Gow, Adam G; Gow, Deborah J; Hall, Edward J; Langton, Debra; Clarke, Chris; Papasouliotis, Kostas

    2009-08-01

    Faecal samples were collected from 57 clinically healthy kittens presented for initial vaccination, in the UK. Routine bacteriological examination identified Salmonella species in one and Campylobacter species in five samples. Polymerase chain reaction (PCR) detected the presence of Campylobacter species in a further four samples. Routine parasitological examination revealed Toxocara species ova in nine (including four kittens stated to have been administered an anthelmintic) and Isospora species in four samples. No Giardia or Cryptosporidium species were detected by routine methods. A Giardia species enzyme-linked immunosorbent assay (ELISA) test kit designed for use in cats was positive in three kittens. A similar test kit designed for use in humans was negative in all samples and produced negative results even when known positive samples were tested. Potentially pathogenic enteric organisms were detected in 19 kittens by routine methods and 26 (prevalence 45%) by all methods. The high prevalence in asymptomatic kittens highlights the possibility that the detection of these organisms in kittens with gastrointestinal disease may be an incidental finding.

  6. A Defective Interfering Influenza RNA Inhibits Infectious Influenza Virus Replication in Human Respiratory Tract Cells: A Potential New Human Antiviral

    PubMed Central

    Smith, Claire M.; Scott, Paul D.; O’Callaghan, Christopher; Easton, Andrew J.; Dimmock, Nigel J.

    2016-01-01

    Defective interfering (DI) viruses arise during the replication of influenza A virus and contain a non-infective version of the genome that is able to interfere with the production of infectious virus. In this study we hypothesise that a cloned DI influenza A virus RNA may prevent infection of human respiratory epithelial cells with infection by influenza A. The DI RNA (244/PR8) was derived by a natural deletion process from segment 1 of influenza A/PR/8/34 (H1N1); it comprises 395 nucleotides and is packaged in the DI virion in place of a full-length genome segment 1. Given intranasally, 244/PR8 DI virus protects mice and ferrets from clinical influenza caused by a number of different influenza A subtypes and interferes with production of infectious influenza A virus in cells in culture. However, evidence that DI influenza viruses are active in cells of the human respiratory tract is lacking. Here we show that 244/PR8 DI RNA is replicated by an influenza A challenge virus in human lung diploid fibroblasts, bronchial epithelial cells, and primary nasal basal cells, and that the yield of challenge virus is significantly reduced in a dose-dependent manner indicating that DI influenza virus has potential as a human antiviral. PMID:27556481

  7. A Defective Interfering Influenza RNA Inhibits Infectious Influenza Virus Replication in Human Respiratory Tract Cells: A Potential New Human Antiviral.

    PubMed

    Smith, Claire M; Scott, Paul D; O'Callaghan, Christopher; Easton, Andrew J; Dimmock, Nigel J

    2016-08-22

    Defective interfering (DI) viruses arise during the replication of influenza A virus and contain a non-infective version of the genome that is able to interfere with the production of infectious virus. In this study we hypothesise that a cloned DI influenza A virus RNA may prevent infection of human respiratory epithelial cells with infection by influenza A. The DI RNA (244/PR8) was derived by a natural deletion process from segment 1 of influenza A/PR/8/34 (H1N1); it comprises 395 nucleotides and is packaged in the DI virion in place of a full-length genome segment 1. Given intranasally, 244/PR8 DI virus protects mice and ferrets from clinical influenza caused by a number of different influenza A subtypes and interferes with production of infectious influenza A virus in cells in culture. However, evidence that DI influenza viruses are active in cells of the human respiratory tract is lacking. Here we show that 244/PR8 DI RNA is replicated by an influenza A challenge virus in human lung diploid fibroblasts, bronchial epithelial cells, and primary nasal basal cells, and that the yield of challenge virus is significantly reduced in a dose-dependent manner indicating that DI influenza virus has potential as a human antiviral.

  8. Antibacterial Potential of Jatropha curcas Synthesized Silver Nanoparticles against Food Borne Pathogens

    PubMed Central

    Chauhan, Nitin; Tyagi, Amit K.; Kumar, Pushpendar; Malik, Anushree

    2016-01-01

    The aqueous leaf extract of Jatropha curcas was used for the synthesis of silver nanoparticles (Jc-AgNps) which were further evaluated for its antibacterial potential against food borne pathogens. J. curcas leaf extract could synthesize stable silver nanoparticles (Zeta potential: -23.4 mV) with absorption band at 430 nm. Fourier transform infrared spectroscopy indicated various biological compounds responsible for capping and stabilizing Jc-AgNps in suspension, while the presence of silver was authenticated by scanning electron microscopy (SEM) equipped with energy-dispersive X-ray. Jc-AgNps were confirmed to be uniform in shape, size and behavior through dynamic light scattering, transmission electron microscopy (TEM), X-ray diffraction, SEM, and atomic force microscopy (AFM) analysis. To investigate the antibacterial activity, disk diffusion and microplate dilution assays were performed and zone of inhibition (ZOI) as well as minimum inhibitory/bactericidal concentrations (MIC/MBCs) were evaluated against selected bacterial strains. Overall results showed that Escherichia coli (ZOI: 23 mm, MBC: 0.010 mg/ml) was the most sensitive organism, whereas Staphylococcus aureus (ZOI: 14.66 mm, MBC: 0.041 mg/ml) and Salmonella enterica (ZOI: 16.66 mm, MBC: 0.041 mg/ml) were the least sensitive against Jc-AgNps. The detailed microscopic investigations using SEM, TEM, and AFM were performed to understand the antibacterial impacts of Jc-AgNps against Listeria monocytogenes. SEM and TEM analysis showed the clear deformation and disintegration of treated L. monocytogenes cells, whereas AFM established a decrease in the height and cell surface roughness (root mean square value) in the treated L. monocytogenes. PMID:27877160

  9. Production of prodigiosin and chitinases by tropical Serratia marcescens strains with potential to control plant pathogens.

    PubMed

    Gutiérrez-Román, Martha Ingrid; Holguín-Meléndez, Francisco; Bello-Mendoza, Ricardo; Guillén-Navarro, Karina; Dunn, Michael F; Huerta-Palacios, Graciela

    2012-01-01

    The potential of three Serratia marcescens strains (CFFSUR-B2, CFFSUR-B3 and CFFSUR-B4) isolated from tropical regions in Mexico to inhibit the mycelial growth and conidial germination of Colletotrichum gloeosporioides, causal agent of fruit anthracnose, was evaluated. The ability of these strains to produce prodigiosin and chitinases when cultivated in oil seed-based media (peanut, sesame, soybean and castor bean) and in Luria-Bertani medium was determined. All of the strains exhibited similar fungal antagonistic activities and inhibited myceliar growth by more than 40% while inhibiting conidial germination by 81-89% (P = 0.01). The highest level of prodigiosin (40 μg/ml) was produced in the peanut-based medium while growth in soybean-based medium allowed the highest production of chitinases (56 units/ml), independent of the strain used. Strain CFFSUR-B2 grown in peanut medium was used to evaluate the effect of inoculum density and initial pH on metabolite production. The amount of prodigiosin produced increased with greater inoculum densities, with an initial density of 1 × 10(12) resulting in the highest production (60 μg/ml). Prodigiosin production was not affected by pH. The strains studied have the advantage of being adapted to tropical climates and are able to produce chitinases in the absence of chitin induction in vitro. These characteristics suggest their potential as biocontrol agents for fungal pathogens in tropical regions of the world.

  10. Assessing Pathogen Levels in Dairy Lagoon Wastewater and Potential Evaporation Losses

    NASA Astrophysics Data System (ADS)

    Pandey, P.; Biswas, S.; Souza, A.; Silva-del-Rio, N.; Vaddella, V. K.; Castillo, A. R.

    2014-12-01

    The ongoing drought in California necessitates the conservation of existing water resources while protecting the water quality. There is a critical need to improve the understanding of evaporation losses from dairy lagoons in California, and their corresponding changes in pathogen levels in the lagoon wastewater. We have carried out preliminary studies involving extensive dairy lagoon water sampling, and batch-scale experiments. The dairy wastewater was collected from both primary and secondary lagoons in three counties of California (Merced, Tulare, and Glenn Counties) for enumerating the levels of E. coli O157:H7, Salmonella spp., and Listeria monocytogenes. Subsequently, we conducted batch-scale experiments at mesophilic (31 and 37 ⁰C) and thermophilic temperatures (43 and 49 ⁰C) to understand the E. coli O157:H7 inactivation process and potential evaporative water losses. In addition, we compared the evaporation losses under the environment of biological activity and the environment of restricted biological activity (extreme environment with low pH). For E. coli O157:H7 enumeration, we used MacConkey agar, while for Salmonella spp., XLD agar was used. Listeria monocytogenes levels were measured using PALCAM agar (with selective supplement). In flushed dairy wastewater (fresh) samples, the average of E. coli O157:H7 levels were 2 × 104 CFU/mL. The average Listeria monocytogenes levels in flushed manure were 9 × 101. The levels of Salmonella spp. were non-detectable. In mesophilic condition (37 ⁰C) after 5 days of incubation, 8% of total water loss was observed, while at thermophilic temperature (49 ⁰C), 70% of total water loss was observed. After 5 days of incubation at 37 ⁰C, E. coli O157:H7 levels in flushed dairy manure were increased from 2.8 × 103 to 5.2 × 104 CFU/mL, while at 49 ⁰C, E. coli O157:H7 levels were reduced from 2.8 × 103 to 5 × 101 CFU/mL after 4 days of incubation. We anticipate that the results of this study would be useful

  11. Porcine respiratory disease complex: Interaction of vaccination and porcine circovirus type 2, porcine reproductive and respiratory syndrome virus, and Mycoplasma hyopneumoniae.

    PubMed

    Chae, Chanhee

    2016-06-01

    Porcine respiratory disease is a multifactorial and complex disease caused by a combination of infectious pathogens, environmental stressors, differences in production systems, and various management practices; hence the name porcine respiratory disease complex (PRDC) is used. Porcine circovirus type 2 (PCV2), porcine reproductive and respiratory syndrome virus (PRRSV), and Mycoplasma hyopneumoniae are considered to be the most important pathogens that cause PRDC. Although interactions among the three major respiratory pathogens are well documented, it is also necessary to understand the interaction between vaccines and the three major respiratory pathogens. PRRSV and M. hyopneumoniae are well known to potentiate PCV2-associated lesions; however, PRRSV and mycoplasmal vaccines can both enhance PCV2 viraemia regardless of the effects of the actual PRRSV or M. hyopneumoniae infection. On the other hand, M. hyopneumoniae potentiates the severity of pneumonia induced by PRRSV, and vaccination against M. hyopneumoniae alone is also able to decrease PRRSV viraemia and PRRSV-induced lung lesions in dually infected pigs. This review focuses on (1) interactions between PCV2, PRRSV, and M. hyopneumoniae; and (2) interactions between vaccines and the three major respiratory pathogens.

  12. Factors Affecting Microbial Load and Profile of Potential Pathogens and Food Spoilage Bacteria from Household Kitchen Tables

    PubMed Central

    Latouche, Melissa Cathleen

    2016-01-01

    The aim was to study the bacterial load and isolate potential pathogens and food spoilage bacteria from kitchen tables, including preparation tables and dining tables. Methods. A total of 53 households gave their consent for participation. The samples were collected by swabbing over an area of 5 cm by 5 cm of the tables and processed for bacterial count which was read as colony forming units (CFU), followed by isolation and identification of potential pathogens and food spoilage bacteria. Result. Knowledge about hygiene was not always put into practice. Coliforms, Enterococcus spp., Pseudomonas spp., Proteus spp., and S. aureus were detected from both dining and preparation tables. The mean CFU and presence of potential pathogens were significantly affected by the hygienic practices of the main food handler of the house, materials of kitchen tables, use of plastic covers, time of sample collection, use of multipurpose sponges/towels for cleaning, and the use of preparation tables as chopping boards (p < 0.05). Conclusion. Kitchen tables could be very important source of potential pathogens and food spoilage bacteria causing foodborne diseases. Lack of hygiene was confirmed by presence of coliforms, S. aureus, and Enterococcus spp. The use of plastic covers, multipurpose sponges, and towels should be discouraged. PMID:27446220

  13. Potential for bio-control of food-borne pathogens with Bacteriovorax spp. and implications for food safety

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bacteriovorax spp. (Bvx) are delta proteobacteria adapted to marine ecosystems where salinity concentration range from 1-3%. Due to their predation of Gram-negative bacteria, Bvx may have great potential for biocontrol of food-borne pathogens on fruits and leafy greens. The goal of this research was...

  14. Factors Affecting Microbial Load and Profile of Potential Pathogens and Food Spoilage Bacteria from Household Kitchen Tables.

    PubMed

    Biranjia-Hurdoyal, Susheela; Latouche, Melissa Cathleen

    2016-01-01

    The aim was to study the bacterial load and isolate potential pathogens and food spoilage bacteria from kitchen tables, including preparation tables and dining tables. Methods. A total of 53 households gave their consent for participation. The samples were collected by swabbing over an area of 5 cm by 5 cm of the tables and processed for bacterial count which was read as colony forming units (CFU), followed by isolation and identification of potential pathogens and food spoilage bacteria. Result. Knowledge about hygiene was not always put into practice. Coliforms, Enterococcus spp., Pseudomonas spp., Proteus spp., and S. aureus were detected from both dining and preparation tables. The mean CFU and presence of potential pathogens were significantly affected by the hygienic practices of the main food handler of the house, materials of kitchen tables, use of plastic covers, time of sample collection, use of multipurpose sponges/towels for cleaning, and the use of preparation tables as chopping boards (p < 0.05). Conclusion. Kitchen tables could be very important source of potential pathogens and food spoilage bacteria causing foodborne diseases. Lack of hygiene was confirmed by presence of coliforms, S. aureus, and Enterococcus spp. The use of plastic covers, multipurpose sponges, and towels should be discouraged.

  15. Middle East Respiratory Syndrome

    PubMed Central

    Zumla, Alimuddin; Hui, David S; Perlman, Stanley

    2016-01-01

    SUMMARY The Middle East Respiratory Syndrome (MERS) is a newly recognized highly lethal respiratory disease caused by a novel single stranded, positive sense RNA betacoronavirus (MERS-CoV). Dromedary camels, host species for MERS-CoV are implicated in the direct or indirect transmission to humans, although the exact mode of transmission remains unknown. First isolated from a patient who died from a severe respiratory illness in June 2012 in Jeddah, Saudi Arabia, as of 16 February 2015, 983 laboratory-confirmed cases of MERS-CoV (360 deaths; 36.6% mortality) were reported to the WHO. Cases have been acquired in both the community and hospitals with limited human-to-human transmission reported in the community. Whilst the majority of MERS cases have occurred in Saudi Arabia and the United Arab Emirates, cases have been reported from Europe, USA and Asia in people who traveled from the Middle East or their contacts. Clinical features of MERS range from asymptomatic or mild disease to acute respiratory distress syndrome and multi-organ failure resulting in death, especially in individuals with underlying co-morbidities. There is no specific drug treatment for MERS and infection prevention and control measures are crucial to prevent spread of MERS-CoV in health care facilities. MERS-CoV continues to be an endemic,low level public health threat. However, the concern remains that the virus could mutate to exhibit increased interhuman transmissibility, increasing pandemic potential. Our seminar presents an overview of current knowledge and perspectives on the epidemiology, virology, mode of transmission, pathogen-host responses, clinical features, diagnosis and development of new drugs and vaccines. PMID:26049252

  16. Distinctive expansion of potential virulence genes in the genome of the oomycete fish pathogen Saprolegnia parasitica.

    PubMed

    Jiang, Rays H Y; de Bruijn, Irene; Haas, Brian J; Belmonte, Rodrigo; Löbach, Lars; Christie, James; van den Ackerveken, Guido; Bottin, Arnaud; Bulone, Vincent; Díaz-Moreno, Sara M; Dumas, Bernard; Fan, Lin; Gaulin, Elodie; Govers, Francine; Grenville-Briggs, Laura J; Horner, Neil R; Levin, Joshua Z; Mammella, Marco; Meijer, Harold J G; Morris, Paul; Nusbaum, Chad; Oome, Stan; Phillips, Andrew J; van Rooyen, David; Rzeszutek, Elzbieta; Saraiva, Marcia; Secombes, Chris J; Seidl, Michael F; Snel, Berend; Stassen, Joost H M; Sykes, Sean; Tripathy, Sucheta; van den Berg, Herbert; Vega-Arreguin, Julio C; Wawra, Stephan; Young, Sarah K; Zeng, Qiandong; Dieguez-Uribeondo, Javier; Russ, Carsten; Tyler, Brett M; van West, Pieter

    2013-06-01

    Oomycetes in the class Saprolegniomycetidae of the Eukaryotic kingdom Stramenopila have evolved as severe pathogens of amphibians, crustaceans, fish and insects, resulting in major losses in aquaculture and damage to aquatic ecosystems. We have sequenced the 63 Mb genome of the fresh water fish pathogen, Saprolegnia parasitica. Approximately 1/3 of the assembled genome exhibits loss of heterozygosity, indicating an efficient mechanism for revealing new variation. Comparison of S. parasitica with plant pathogenic oomycetes suggests that during evolution the host cellular environment has driven distinct patterns of gene expansion and loss in the genomes of plant and animal pathogens. S. parasitica possesses one of the largest repertoires of proteases (270) among eukaryotes that are deployed in waves at different points during infection as determined from RNA-Seq data. In contrast, despite being capable of living saprotrophically, parasitism has led to loss of inorganic nitrogen and sulfur assimilation pathways, strikingly similar to losses in obligate plant pathogenic oomycetes and fungi. The large gene families that are hallmarks of plant pathogenic oomycetes such as Phytophthora appear to be lacking in S. parasitica, including those encoding RXLR effectors, Crinkler's, and Necrosis Inducing-Like Proteins (NLP). S. parasitica also has a very large kinome of 543 kinases, 10% of which is induced upon infection. Moreover, S. parasitica encodes several genes typical of animals or animal-pathogens and lacking from other oomycetes, including disintegrins and galactose-binding lectins, whose expression and evolutionary origins implicate horizontal gene transfer in the evolution of animal pathogenesis in S. parasitica.

  17. Respiratory System

    MedlinePlus

    ... this page from the NHLBI on Twitter. The Respiratory System The respiratory system is made up of organs ... vessels, and the muscles that enable breathing. The Respiratory System Figure A shows the location of the respiratory ...

  18. Transient virulence of emerging pathogens.

    PubMed

    Bolker, Benjamin M; Nanda, Arjun; Shah, Dharmini

    2010-05-06

    Should emerging pathogens be unusually virulent? If so, why? Existing theories of virulence evolution based on a tradeoff between high transmission rates and long infectious periods imply that epidemic growth conditions will select for higher virulence, possibly leading to a transient peak in virulence near the beginning of an epidemic. This transient selection could lead to high virulence in emerging pathogens. Using a simple model of the epidemiological and evolutionary dynamics of emerging pathogens, along with rough estimates of parameters for pathogens such as severe acute respiratory syndrome, West Nile virus and myxomatosis, we estimated the potential magnitude and timing of such transient virulence peaks. Pathogens that are moderately evolvable, highly transmissible, and highly virulent at equilibrium could briefly double their virulence during an epidemic; thus, epidemic-phase selection could contribute significantly to the virulence of emerging pathogens. In order to further assess the potential significance of this mechanism, we bring together data from the literature for the shapes of tradeoff curves for several pathogens (myxomatosis, HIV, and a parasite of Daphnia) and the level of genetic variation for virulence for one (myxomatosis). We discuss the need for better data on tradeoff curves and genetic variance in order to evaluate the plausibility of various scenarios of virulence evolution.

  19. Antimicrobial resistance among respiratory pathogens in Spain: latest data and changes over 11 years (1996-1997 to 2006-2007).

    PubMed

    Pérez-Trallero, Emilio; Martín-Herrero, Jose E; Mazón, Ana; García-Delafuente, Celia; Robles, Purificación; Iriarte, Victor; Dal-Ré, Rafael; García-de-Lomas, Juan

    2010-07-01

    A nationwide multicenter susceptibility surveillance study (Susceptibility to the Antimicrobials Used in the Community in España [SAUCE] project), SAUCE-4, including 2,559 Streptococcus pneumoniae, 2,287 Streptococcus pyogenes, and 2,736 Haemophilus influenzae isolates was carried out from May 2006 to June 2007 in 34 Spanish hospitals. Then, the results from SAUCE-4 were compared to those from all three previous SAUCE studies carried out in 1996-1997, 1998-1999, and 2001-2002 to assess the temporal trends in resistance and the phenotypes of resistance over the 11-year period. In SAUCE-4, on the basis of the CLSI breakpoints, penicillin (parenteral, nonmeningitis breakpoint) and cefotaxime were the antimicrobials that were the most active against S. pneumoniae (99.8% and 99.6%, respectively). Only 0.9% of isolates had a penicillin MIC of > or = 2 microg/ml. In S. pyogenes, nonsusceptibility to erythromycin was observed in 19.4% of isolates. Among the H. influenzae isolates, a beta-lactamase-positive prevalence of 15.7% was found. A statistically significant temporal decreasing trend over the 11-year period was observed for nonsusceptibility (from 60.0% to 22.9%) and resistance (from 36.5% to 0.9%) to penicillin and for the proportion of erythromycin-resistant isolates of S. pneumoniae of the macrolide-lincosamide-streptogramin B (MLS(B)) phenotype (from 98.4% to 81.3%). A similar trend was observed for the prevalence of ampicillin resistance (from 37.6% to 16.1%), beta-lactamase production (from 25.7% to 15.7%), and beta-lactamase-negative ampicillin resistance (BLNAR) in H. influenzae (from 13.5% to 0.7%). Among erythromycin-resistant isolates of S. pyogenes, a significant increasing trend in the prevalence of MLS(B) was observed (from 7.0% to 35.5%). SAUCE-4 confirms a generalized decline in the resistance of the main respiratory pathogens to the antimicrobials as well as a shift in their resistance phenotypes.

  20. Antimicrobial Resistance among Respiratory Pathogens in Spain: Latest Data and Changes over 11 Years (1996-1997 to 2006-2007)▿

    PubMed Central

    Pérez-Trallero, Emilio; Martín-Herrero, Jose E.; Mazón, Ana; García-Delafuente, Celia; Robles, Purificación; Iriarte, Victor; Dal-Ré, Rafael; García-de-Lomas, Juan

    2010-01-01

    A nationwide multicenter susceptibility surveillance study (Susceptibility to the Antimicrobials Used in the Community in España [SAUCE] project), SAUCE-4, including 2,559 Streptococcus pneumoniae, 2,287 Streptococcus pyogenes, and 2,736 Haemophilus influenzae isolates was carried out from May 2006 to June 2007 in 34 Spanish hospitals. Then, the results from SAUCE-4 were compared to those from all three previous SAUCE studies carried out in 1996-1997, 1998-1999, and 2001-2002 to assess the temporal trends in resistance and the phenotypes of resistance over the 11-year period. In SAUCE-4, on the basis of the CLSI breakpoints, penicillin (parenteral, nonmeningitis breakpoint) and cefotaxime were the antimicrobials that were the most active against S. pneumoniae (99.8% and 99.6%, respectively). Only 0.9% of isolates had a penicillin MIC of ≥2 μg/ml. In S. pyogenes, nonsusceptibility to erythromycin was observed in 19.4% of isolates. Among the H. influenzae isolates, a β-lactamase-positive prevalence of 15.7% was found. A statistically significant temporal decreasing trend over the 11-year period was observed for nonsusceptibility (from 60.0% to 22.9%) and resistance (from 36.5% to 0.9%) to penicillin and for the proportion of erythromycin-resistant isolates of S. pneumoniae of the macrolide-lincosamide-streptogramin B (MLSB) phenotype (from 98.4% to 81.3%). A similar trend was observed for the prevalence of ampicillin resistance (from 37.6% to 16.1%), β-lactamase production (from 25.7% to 15.7%), and β-lactamase-negative ampicillin resistance (BLNAR) in H. influenzae (from 13.5% to 0.7%). Among erythromycin-resistant isolates of S. pyogenes, a significant increasing trend in the prevalence of MLSB was observed (from 7.0% to 35.5%). SAUCE-4 confirms a generalized decline in the resistance of the main respiratory pathogens to the antimicrobials as well as a shift in their resistance phenotypes. PMID:20439616

  1. Reptiles as potential vectors and hosts of the amphibian pathogen Batrachochytrium dendrobatidis in Panama.

    PubMed

    Kilburn, Vanessa L; Ibáñez, Roberto; Green, David M

    2011-12-06

    Chytridiomycosis, the disease caused by Batrachochytrium dendrobatidis, is considered to be a disease exclusively of amphibians. However, B. dendrobatidis may also be capable of persisting in the environment, and non-amphibian vectors or hosts may contribute to disease transmission. Reptiles living in close proximity to amphibians and sharing similar ecological traits could serve as vectors or reservoir hosts for B. dendrobatidis, harbouring the organism on their skin without succumbing to disease. We surveyed for the presence of B. dendrobatidis DNA among 211 lizards and 8 snakes at 8 sites at varying elevations in Panama where the syntopic amphibians were at pre-epizootic, epizootic or post-epizootic stages of chytridiomycosis. Detection of B. dendrobatidis DNA was done using qPCR analysis. Evidence of the amphibian pathogen was present at varying intensities in 29 of 79 examined Anolis humilis lizards (32%) and 9 of 101 A. lionotus lizards (9%), and in one individual each of the snakes Pliocercus euryzonus, Imantodes cenchoa, and Nothopsis rugosus. In general, B. dendrobatidis DNA prevalence among reptiles was positively correlated with the infection prevalence among co-occurring anuran amphibians at any particular site (r = 0.88, p = 0.004). These reptiles, therefore, may likely be vectors or reservoir hosts for B. dendrobatidis and could serve as disease transmission agents. Although there is no evidence of B. dendrobatidis disease-induced declines in reptiles, cases of coincidence of reptile and amphibian declines suggest this potentiality. Our study is the first to provide evidence of non-amphibian carriers for B. dendrobatidis in a natural Neotropical environment.

  2. Potential of Cerbera odollam as a bio-fungicide for post-harvest pathogen Penicilium digitatum

    NASA Astrophysics Data System (ADS)

    Singh, Harbant; Yin-Chu, Sue; Al-Samarrai, Ghassan; Syarhabil, Muhammad

    2015-05-01

    Postharvest diseases due to fungal infection contribute to economic losses in agriculture industry during storage, transportation or in the market. Penicillium digitatum is one of the common pathogen responsible for the postharvest rot in fruits. This disease is currently being controlled by synthetic fungicides such as Guazatine and Imazalil. However, heavy use of fungicides has resulted in environmental pollution, such as residue in fruit that expose a significant risk to human health. Therefore, there is a strong need to develop alternatives to synthetic fungicide to raise customer confidence. In the current research, different concentrations (500 to 3000 ppm) of ethanol extract of Cerbera odollam or commonly known as Pong-pong were compared with Neem and the controls (Positive control/Guazatine; Negative control/DMSO) for the anti-fungicide activity in PDA media contained in 10 cm diameter Petri dishes, using a modification of Ruch and Worf's method. The toxicity (Lc50) of the C.odollam extract was determined by Brine-shrimp test (BST). The results of the research indicated that crude extraction from C.odollam showed the highest inhibition rate (93%) and smallest colony diameter (0.63 cm) at 3000 ppm in vitro compared with Neem (inhibition rate: 88%; colony diameter: 1.33 cm) and control (Positive control/Guazatine inhibition rate: 79%, colony diameter: 1.9 cm; Negative control/DMSO inhibition rate: 0%, colony diameter: 9.2 cm). C.odollam recorded Lc50 value of 5 µg/ml which is safe but to be used with caution (unsafe level: below 2 µg/ml). The above anti-microbial activity and toxicity value results indicate that C.odollam has a potential of being a future bio-fungicide that could be employed as an alternative to synthetic fungicide.

  3. Molecular identification of potential pathogens in water and air of a hospital therapy pool

    PubMed Central

    Angenent, Largus T.; Kelley, Scott T.; Amand, Allison St.; Pace, Norman R.; Hernandez, Mark T.

    2005-01-01

    Indoor warm-water therapy pool workers in a Midwestern regional hospital were diagnosed with non-tuberculosis pulmonary hypersensitive pneumonitis and Mycobacterium avium infections. In response, we conducted a multiseason survey of microorganisms present in this therapy pool water, in biofilms associated with the pool containment walls, and in air immediately above the pool. The survey used culture, microscopy, and culture-independent molecular phylogenetic analyses. Although outfitted with a state-of-the-art UV-peroxide disinfection system, the numbers of bacteria in the therapy pool water were relatively high compared with the potable water used to fill the pool. Regardless of the source, direct microscopic counts of microbes were routinely ≈1,000 times greater than conventional plate counts. Analysis of clone libraries of small subunit rRNA genes from environmental DNA provided phylogenetic diversity estimates of the microorganisms collected in and above the pool. A survey of >1,300 rRNA genes yielded a total of 628 unique sequences, the most common of which was nearly identical to that of M. avium strains. The high proportion of clones with different Mycobacterium spp. rRNA genes suggested that such organisms comprised a significant fraction of microbes in the pool water (to >30%) and preferentially partition into aerosols (to >80%) relative to other waterborne bacteria present. The results of the study strongly validate aerosol partitioning as a mechanism for disease transfer in these environments. The results also show that culture protocols currently used by public health facilities and agencies are seriously inadequate for the detection and enumeration of potential pathogens. PMID:15769858

  4. Use of ex vivo and in vitro cultures of the human respiratory tract to study the tropism and host responses of highly pathogenic avian influenza A (H5N1) and other influenza viruses.

    PubMed

    Chan, Renee W Y; Chan, Michael C W; Nicholls, John M; Malik Peiris, J S

    2013-12-05

    The tropism of influenza viruses for the human respiratory tract is a key determinant of host-range, and consequently, of pathogenesis and transmission. Insights can be obtained from clinical and autopsy studies of human disease and relevant animal models. Ex vivo cultures of the human respiratory tract and in vitro cultures of primary human cells can provide complementary information provided they are physiologically comparable in relevant characteristics to human tissues in vivo, e.g. virus receptor distribution, state of differentiation. We review different experimental models for their physiological relevance and summarize available data using these cultures in relation to highly pathogenic avian influenza H5N1, in comparison where relevant, with other influenza viruses. Transformed continuous cell-lines often differ in important ways to the corresponding tissues in vivo. The state of differentiation of primary human cells (respiratory epithelium, macrophages) can markedly affect virus tropism and host responses. Ex vivo cultures of human respiratory tissues provide a close resemblance to tissues in vivo and may be used to risk assess animal viruses for pandemic threat. Physiological factors (age, inflammation) can markedly affect virus receptor expression and virus tropism. Taken together with data from clinical studies on infected humans and relevant animal models, data from ex vivo and in vitro cultures of human tissues and cells can provide insights into virus transmission and pathogenesis and may provide understanding that leads to novel therapeutic interventions.

  5. Virulence-related genes, adhesion and invasion of some Yersinia enterocolitica-like strains suggests its pathogenic potential.

    PubMed

    Imori, Priscilla F M; Passaglia, Jaqueline; Souza, Roberto A; Rocha, Lenaldo B; Falcão, Juliana P

    2017-03-01

    Yersina enterocolitica-like species have not been extensively studied regarding its pathogenic potential. This work aimed to assess the pathogenic potential of some Y. enterocolitica-like strains by evaluating the presence of virulence-related genes by PCR and their ability to adhere to and invade Caco-2 and HEp-2 cells. A total of 50 Y. frederiksenii, 55 Y. intermedia and 13 Y. kristensenii strains were studied. The strains contained the following genes: Y. frederiksenii, fepA(44%), fes(44%) and ystB(18%); Y. intermedia, ail(53%), fepA (35%), fepD(2%), fes(97%), hreP(2%), ystB(2%) and tccC(35%); Y. kristensenii, ail(62%), ystB(23%), fepA(77%), fepD(54%), fes(54%) and hreP(77%). Generally, the Y. enterocolitica-like strains had a reduced ability to adhere to and invade mammalian cells compared to the highly pathogenic Y. enterocolitica 8081. However, Y. kristensenii FCF410 and Y. frederiksenii FCF461 presented high invasion potentials in Caco-2 cells after five days of pre-incubation increased by 45- and 7.2-fold compared to Y. enterocolitica 8081, respectively; but, the ail gene was not detected in these strains. The presence of virulence-related genes in some of the Y. enterocolitica-like strains indicated their possible pathogenic potential. Moreover, the results suggest the existence of alternative virulence mechanisms and that the pathogenicity of Y. kristensenii and Y. frederiksenii may be strain-dependent.

  6. In Vitro Assessment of the Probiotic Potential of Lactococcus lactis LMG 7930 against Ruminant Mastitis-Causing Pathogens

    PubMed Central

    Armas, Federica; Camperio, Cristina

    2017-01-01

    Mastitis in dairy ruminants is considered to be the most expensive disease to farmers worldwide. Recently, the intramammary infusion of lactic acid bacteria has emerged as a potential new alternative to antibiotics for preventing and treating bovine mastitis. In this study we have investigated in vitro the probiotic potential of Lactococcus lactis LMG 7930, a food-grade and nisin-producing strain, against mastitis-causing pathogens. We have characterized its carbohydrate fermentation and antibiotic susceptibility profiles, cell surface properties and antimicrobial activity, as well as its capabilities to adhere to and inhibit the invasion of pathogens into the bovine mammary epithelial cell line BME-UV1d. We found that L. lactis LMG 7930 was sensitive to tested drugs, according to the EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP), and showed an improved carbohydrate fermentation capacity compared to starter strains. Moreover, the strain exhibited antagonistic properties towards many of the pathogens tested. It presented medium surface hydrophobicity, a low basic property and no electron acceptor capability. It showed low auto-aggregation and no co-aggregation abilities towards any of the tested pathogens. The strain was one of the most adhesive to bovine mammary epithelial cells among tested bacteria, but its internalisation was low. The strain did not affect significantly pathogen invasion; however, a trend to decrease internalization of some pathogens tested was observed. In conclusion, our results suggest that this strain might be a promising candidate for the development of new strategies of mastitis control in ruminants. Future investigations are needed to evaluate its safety and efficacy under field conditions. PMID:28068371

  7. Secretome analysis identifies potential virulence factors of Diplodia corticola, a fungal pathogen involved in cork oak (Quercus suber) decline.

    PubMed

    Fernandes, Isabel; Alves, Artur; Correia, António; Devreese, Bart; Esteves, Ana Cristina

    2014-01-01

    The characterisation of the secretome of phytopathogenic fungi may contribute to elucidate the molecular mechanisms of pathogenesis. This is particularly relevant for Diplodia corticola, a fungal plant pathogen belonging to the family Botryosphaeriaceae, whose genome remains unsequenced. This phytopathogenic fungus is recognised as one of the most important pathogens of cork oak, being related to the decline of cork oak forests in the Iberian Peninsula. Unfortunately, secretome analysis of filamentous fungi is limited by the low protein concentration and by the presence of many interfering substances, such as polysaccharides, which affect the separation and analysis by 1D and 2D gel electrophoresis. We compared six protein extraction protocols concerning their suitability for further application with proteomic workflows. The protocols involving protein precipitation were the most efficient, with emphasis on TCA-acetone protocol, allowing us to identify the most abundant proteins on the secretome of this plant pathogen. Approximately 60% of the spots detected were identified, all corresponding to extracellular proteins. Most proteins identified were carbohydrate degrading enzymes and proteases that may be related to D. corticola pathogenicity. Although the secretome was assessed in a noninfection environment, potential virulence factors such as the putative glucan-β-glucosidase, neuraminidase, and the putative ferulic acid esterase were identified. The data obtained forms a useful basis for a deeper understanding of the pathogenicity and infection biology of D. corticola. Moreover, it will contribute to the development of proteomics studies on other members of the Botryosphaeriaceae.

  8. Determining the Pathogenic Potential of Non-sporulating Molds Isolated from Cutaneous Specimens.

    PubMed

    Jeyaprakasam, Nantha Kumar; Razak, Mohd Fuat Abdul; Ahmad, Noor Azimah Binti; Santhanam, Jacinta

    2016-06-01

    Although non-sporulating molds (NSM) are frequently isolated from patients and have been recognized as agents of pulmonary disease, their clinical significance in cutaneous specimens is relatively unknown. Therefore, this study aimed to identify NSM and to determine the keratinolytic activity of isolates from cutaneous sites. NSM isolates from clinical specimens such as skin, nail, and body fluids were identified based on their ribosomal DNA sequences. Of 17 NSM isolates (7 Ascomycota, 10 Basidiomycota), eleven were identified to species level while five were identified to the genus level. These include Schizophyllum commune, a known human pathogen, Phoma multirostrata, a plant pathogen, and Perenniporia tephropora, a saprophyte. To determine fungal pathogenicity, keratinolytic activity, a major virulence factor, was evaluated ex vivo using human nail samples by measuring dye release from keratin azure, for NSM along with pathogens (Trichophyton mentagrophytes, Trichophyton rubrum, Microsporum canis and Fusarium spp.) and nonpathogenic (endophyte) fungi for comparison. This study showed that pathogenic fungi had the highest keratinolytic activity (7.13 ± 0.552 keratinase units) while the nonpathogenic endophytes had the lowest activity (2.37 ± 0.262 keratinase units). Keratinolytic activity of two Ascomycota NSM (Guignardia mangiferae and Hypoxylon sp.) and one Basidiomycota NSM (Fomitopsis cf. meliae) was equivalent to that of pathogenic fungi, while Xylaria feejeensis showed significantly higher activity (p < 0.05) than nonpathogenic endophytes. These results indicate that the pathogenic ability of NSM is species dependent; clinical isolates, especially more frequently isolated species, may be involved in disease etiology.

  9. Distinctive Expansion of Potential Virulence Genes in the Genome of the Oomycete Fish Pathogen Saprolegnia parasitica

    PubMed Central

    Belmonte, Rodrigo; Löbach, Lars; Christie, James; van den Ackerveken, Guido; Bottin, Arnaud; Bulone, Vincent; Díaz-Moreno, Sara M.; Dumas, Bernard; Fan, Lin; Gaulin, Elodie; Govers, Francine; Grenville-Briggs, Laura J.; Horner, Neil R.; Levin, Joshua Z.; Mammella, Marco; Meijer, Harold J. G.; Morris, Paul; Nusbaum, Chad; Oome, Stan; Phillips, Andrew J.; van Rooyen, David; Rzeszutek, Elzbieta; Saraiva, Marcia; Secombes, Chris J.; Seidl, Michael F.; Snel, Berend; Stassen, Joost H. M.; Sykes, Sean; Tripathy, Sucheta; van den Berg, Herbert; Vega-Arreguin, Julio C.; Wawra, Stephan; Young, Sarah K.; Zeng, Qiandong; Dieguez-Uribeondo, Javier; Russ, Carsten; Tyler, Brett M.; van West, Pieter

    2013-01-01

    Oomycetes in the class Saprolegniomycetidae of the Eukaryotic kingdom Stramenopila have evolved as severe pathogens of amphibians, crustaceans, fish and insects, resulting in major losses in aquaculture and damage to aquatic ecosystems. We have sequenced the 63 Mb genome of the fresh water fish pathogen, Saprolegnia parasitica. Approximately 1/3 of the assembled genome exhibits loss of heterozygosity, indicating an efficient mechanism for revealing new variation. Comparison of S. parasitica with plant pathogenic oomycetes suggests that during evolution the host cellular environment has driven distinct patterns of gene expansion and loss in the genomes of plant and animal pathogens. S. parasitica possesses one of the largest repertoires of proteases (270) among eukaryotes that are deployed in waves at different points during infection as determined from RNA-Seq data. In contrast, despite being capable of living saprotrophically, parasitism has led to loss of inorganic nitrogen and sulfur assimilation pathways, strikingly similar to losses in obligate plant pathogenic oomycetes and fungi. The large gene families that are hallmarks of plant pathogenic oomycetes such as Phytophthora appear to be lacking in S. parasitica, including those encoding RXLR effectors, Crinkler's, and Necrosis Inducing-Like Proteins (NLP). S. parasitica also has a very large kinome of 543 kinases, 10% of which is induced upon infection. Moreover, S. parasitica encodes several genes typical of animals or animal-pathogens and lacking from other oomycetes, including disintegrins and galactose-binding lectins, whose expression and evolutionary origins implicate horizontal gene transfer in the evolution of animal pathogenesis in S. parasitica. PMID:23785293

  10. Evaluation of the pathogenic potential, antimicrobial susceptibility, and genomic relations of Yersinia enterocolitica strains from food and human origin.

    PubMed

    Lucero-Estrada, Cecilia S M; Soria, José Miguel; Favier, Gabriela Isabel; Escudero, María Esther

    2015-11-01

    Yersinia enterocolitica is a food-borne pathogen that causes gastroenteritis with occasional postinfection sequels. This study was aimed to determinate the pathogenic potential, antimicrobial susceptibility, and genomic relationships of Y. enterocolitica strains of different bioserotypes (B/O) isolated from foods and human samples in San Luis, Argentina. Strains obtained by culture were bioserotyped and characterized by phenotypic and genotypic virulence markers, antimicrobial susceptibility, and pulsed-field gel electrophoresis (PFGE). Yersinia enterocolitica was detected in 9.2% of 380 samples, with a distribution of 10.6% (30/284) for food products and 5.2% (5/96) for human samples. Regarding the pathogenic potential, B1A strains of different serotypes were virF(-) ail(-), of which 72.0% (13/18) were ystB(+) with virulence-related phenotypic characteristics. Among B2/O:9 isolates, 75.0% (9/12) exhibited the genotype virF(+) ail(+) ystB(-) along with phenotypic traits associated with virulence; the same genotype was observed in 80.0% (4/5) of B3/O:3 and B3/O:5 strains. By PFGE, it was possible to separate Y. enterocolitica biotypes into 4 clonal groups (A to D) with 23 genomic types, generating a discriminatory index of 0.96. All isolates were susceptible to antimicrobials used for clinical treatment. This study highlights the presence of pathogenic bioserotypes and the high genomic diversity of the Y. enterocolitica strains isolated in our region.

  11. Bacteriophages with potential for inactivation of fish pathogenic bacteria: survival, host specificity and effect on bacterial community structure.

    PubMed

    Pereira, Carla; Silva, Yolanda J; Santos, Ana L; Cunha, Angela; Gomes, Newton C M; Almeida, Adelaide

    2011-01-01

    Phage therapy may represent a viable alternative to antibiotics to inactivate fish pathogenic bacteria. Its use, however, requires the awareness of novel kinetics phenomena not applied to conventional drug treatments. The main objective of this work was to isolate bacteriophages with potential to inactivate fish pathogenic bacteria, without major effects on the structure of natural bacterial communities of aquaculture waters. The survival was determined in marine water, through quantification by the soft agar overlay technique. The host specificity was evaluated by cross infection. The ecological impact of phage addition on the structure of the bacterial community was evaluated by DGGE of PCR amplified 16S rRNA gene fragments. The survival period varied between 12 and 91 days, with a higher viability for Aeromonas salmonicida phages. The phages of Vibrio parahaemolyticus and of A. salmonicida infected bacteria of different families with a high efficacy of plating. The specific phages of pathogenic bacteria had no detectable impact on the structure of the bacterial community. In conclusion, V. parahaemolyticus and A. salmonicida phages show good survival time in marine water, have only a moderated impact on the overall bacterial community structure and the desired specificity for host pathogenic bacteria, being potential candidates for therapy of fish infectious diseases in marine aquaculture systems.

  12. Potential Application of Viral Empty Capsids for the Treatment of Acute Lung Injury/Acute Respiratory Distress Syndrome

    DTIC Science & Technology

    2016-07-01

    Acute Respiratory Distress Syndrome PRINCIPAL INVESTIGATOR: Prof. Ariella Oppenheim CONTRACTING ORGANIZATION: Hebrew University of Jerusalem...Lung / 5a. CONTRACT NUMBER Injury/Acute Respiratory Distress Syndrome 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Prof. Ariella...mechanism elicited by VLPs that attenuate 2CLP-induced sepsis, to be performed as the project continues. 15. SUBJECT TERMS Acute Respiratory Distress

  13. Potential role of bacteria packaging by protozoa in the persistence and transmission of pathogenic bacteria

    PubMed Central

    Denoncourt, Alix M.; Paquet, Valérie E.; Charette, Steve J.

    2014-01-01

    Many pathogenic bacteria live in close association with protozoa. These unicellular eukaryotic microorganisms are ubiquitous in various environments. A number of protozoa such as amoebae and ciliates ingest pathogenic bacteria, package them usually in membrane structures, and then release them into the environment. Packaged bacteria are more resistant to various stresses and are more apt to survive than free bacteria. New evidence indicates that protozoa and not bacteria control the packaging process. It is possible that packaging is more common than suspected and may play a major role in the persistence and transmission of pathogenic bacteria. To confirm the role of packaging in the propagation of infections, it is vital that the molecular mechanisms governing the packaging of bacteria by protozoa be identified as well as elements related to the ecology of this process in order to determine whether packaging acts as a Trojan Horse. PMID:24904553

  14. Potential role of bacteria packaging by protozoa in the persistence and transmission of pathogenic bacteria.

    PubMed

    Denoncourt, Alix M; Paquet, Valérie E; Charette, Steve J

    2014-01-01

    Many pathogenic bacteria live in close association with protozoa. These unicellular eukaryotic microorganisms are ubiquitous in various environments. A number of protozoa such as amoebae and ciliates ingest pathogenic bacteria, package them usually in membrane structures, and then release them into the environment. Packaged bacteria are more resistant to various stresses and are more apt to survive than free bacteria. New evidence indicates that protozoa and not bacteria control the packaging process. It is possible that packaging is more common than suspected and may play a major role in the persistence and transmission of pathogenic bacteria. To confirm the role of packaging in the propagation of infections, it is vital that the molecular mechanisms governing the packaging of bacteria by protozoa be identified as well as elements related to the ecology of this process in order to determine whether packaging acts as a Trojan Horse.

  15. Genomic reconnaissance of clinical isolates of emerging human pathogen Mycobacterium abscessus reveals high evolutionary potential

    PubMed Central

    Choo, Siew Woh; Wee, Wei Yee; Ngeow, Yun Fong; Mitchell, Wayne; Tan, Joon Liang; Wong, Guat Jah; Zhao, Yongbing; Xiao, Jingfa

    2014-01-01

    Mycobacterium abscessus (Ma) is an emerging human pathogen that causes both soft tissue infections and systemic disease. We present the first comparative whole-genome study of Ma strains isolated from patients of wide geographical origin. We found a high proportion of accessory strain-specific genes indicating an open, non-conservative pan-genome structure, and clear evidence of rapid phage-mediated evolution. Although we found fewer virulence factors in Ma compared to M. tuberculosis, our data indicated that Ma evolves rapidly and therefore should be monitored closely for the acquisition of more pathogenic traits. This comparative study provides a better understanding of Ma and forms the basis for future functional work on this important pathogen. PMID:24515248

  16. Ralstonia solanacearum strains from Martinique (French West Indies) exhibiting a new pathogenic potential.

    PubMed

    Wicker, Emmanuel; Grassart, Laurence; Coranson-Beaudu, Régine; Mian, Danièle; Guilbaud, Caroline; Fegan, Mark; Prior, Philippe

    2007-11-01

    We investigated a destructive pathogenic variant of the plant pathogen Ralstonia solanacearum that was consistently isolated in Martinique (French West Indies). Since the 1960s, bacterial wilt of solanaceous crops in Martinique has been caused primarily by strains of R. solanacearum that belong to either phylotype I or phylotype II. Since 1999, anthurium shade houses have been dramatically affected by uncharacterized phylotype II strains that also affected a wide range of species, such as Heliconia caribea, cucurbitaceous crops, and weeds. From 1989 to 2003, a total of 224 R. solanacearum isolates were collected and compared to 6 strains isolated in Martinique in the 1980s. The genetic diversity and phylogenetic position of selected strains from Martinique were assessed (multiplex PCRs, mutS and egl DNA sequence analysis) and compared to the genetic diversity and phylogenetic position of 32 reference strains covering the known diversity within the R. solanacearum species complex. Twenty-four representative isolates were tested for pathogenicity to Musa species (banana) and tomato, eggplant, and sweet pepper. Based upon both PCR and sequence analysis, 119 Martinique isolates from anthurium, members of the family Cucurbitaceae, Heliconia, and tomato, were determined to belong to a group termed phylotype II/sequevar 4 (II/4). While these strains cluster with the Moko disease-causing strains, they were not pathogenic to banana (NPB). The strains belonging to phylotype II/4NPB were highly pathogenic to tomato, eggplant, and pepper, were able to wilt the resistant tomato variety Hawaii7996, and may latently infect cooking banana. Phylotype II/4NPB constitutes a new pathogenic variant of R. solanacearum that has recently appeared in Martinique and may be latently prevalent throughout Caribbean and Central/South America.

  17. Carbon nanotubes as delivery systems for respiratory disease: do the dangers outweigh the potential benefits?

    PubMed

    Bonner, James C

    2011-12-01

    Nanoparticle drug-delivery systems offer the potential for improved efficacy of treatment, and yet there are also potential risks associated with these novel therapeutic strategies. An attractive property of carbon nanotubes (CNTs) is that the tube- or fiber-like structure allows for extensive functionalization and loading of cargo. However, a large body of evidence indicates that CNTs may have adverse effects if used in drug delivery as they have been shown to cause pulmonary fibrosis and exacerbate lung disease in rodents with pre-existing lung diseases. Major factors that cause these toxic effects are the high aspect ratio, durability and residual metal content that generate reactive oxygen species. Therefore, careful consideration should be given to the possibility that lung inflammation or fibrosis could be significant side effects caused by a CNT-based drug-delivery system, thereby outweighing any potential beneficial effects of therapeutic treatment. However, functionalization of CNTs to modulate aspect ratio, biodegradability and to remove residual metals could allow for safe design of CNTs for use in drug delivery in certain circumstances.

  18. A novel nanobody specific for respiratory surfactant protein A has potential for lung targeting

    PubMed Central

    Wang, Shan-Mei; He, Xian; Li, Nan; Yu, Feng; Hu, Yang; Wang, Liu-Sheng; Zhang, Peng; Du, Yu-Kui; Du, Shan-Shan; Yin, Zhao-Fang; Wei, Ya-Ru; Mulet, Xavier; Coia, Greg; Weng, Dong; He, Jian-Hua; Wu, Min; Li, Hui-Ping

    2015-01-01

    Lung-targeting drugs are thought to be potential therapies of refractory lung diseases by maximizing local drug concentrations in the lung to avoid systemic circulation. However, a major limitation in developing lung-targeted drugs is the acquirement of lung-specific ligands. Pulmonary surfactant protein A (SPA) is predominantly synthesized by type II alveolar epithelial cells, and may serve as a potential lung-targeting ligand. Here, we generated recombinant rat pulmonary SPA (rSPA) as an antigen and immunized an alpaca to produce two nanobodies (the smallest naturally occurring antibodies) specific for rSPA, designated Nb6 and Nb17. To assess these nanobodies’ potential for lung targeting, we evaluated their specificity to lung tissue and toxicity in mice. Using immunohistochemistry, we demonstrated that these anti-rSPA nanobodies selectively bound to rat lungs with high affinity. Furthermore, we intravenously injected fluorescein isothiocyanate-Nb17 in nude mice and observed its preferential accumulation in the lung to other tissues, suggesting high affinity of the nanobody for the lung. Studying acute and chronic toxicity of Nb17 revealed its safety in rats without causing apparent histological alterations. Collectively, we have generated and characterized lung-specific nanobodies, which may be applicable for lung drug delivery. PMID:25926731

  19. Benefits of a European Project on Diagnostics of Highly Pathogenic Agents and Assessment of Potential “Dual Use” Issues

    PubMed Central

    Grunow, Roland; Ippolito, G.; Jacob, D.; Sauer, U.; Rohleder, A.; Di Caro, A.; Iacovino, R.

    2014-01-01

    Quality assurance exercises and networking on the detection of highly infectious pathogens (QUANDHIP) is a joint action initiative set up in 2011 that has successfully unified the primary objectives of the European Network on Highly Pathogenic Bacteria (ENHPB) and of P4-laboratories (ENP4-Lab) both of which aimed to improve the efficiency, effectiveness, and response capabilities of laboratories directed at protecting the health of European citizens against high consequence bacteria and viruses of significant public health concern. Both networks have established a common collaborative consortium of 37 nationally and internationally recognized institutions with laboratory facilities from 22 European countries. The specific objectives and achievements include the initiation and establishment of a recognized and acceptable quality assurance scheme, including practical external quality assurance exercises, comprising living agents, that aims to improve laboratory performance, accuracy, and detection capabilities in support of patient management and public health responses; recognized training schemes for diagnostics and handling of highly pathogenic agents; international repositories comprising highly pathogenic bacteria and viruses for the development of standardized reference material; a standardized and transparent Biosafety and Biosecurity strategy protecting healthcare personnel and the community in dealing with high consequence pathogens; the design and organization of response capabilities dealing with cross-border events with highly infectious pathogens including the consideration of diagnostic capabilities of individual European laboratories. The project tackled several sensitive issues regarding Biosafety, Biosecurity and “dual use” concerns. The article will give an overview of the project outcomes and discuss the assessment of potential “dual use” issues. PMID:25426479

  20. Transient receptor potential (TRP) channels as a therapeutic target for intervention of respiratory effects and lethality from phosgene.

    PubMed

    Andres, Devon; Keyser, Brian; Benton, Betty; Melber, Ashley; Olivera, Dorian; Holmes, Wesley; Paradiso, Danielle; Anderson, Dana; Ray, Radharaman

    2016-02-26

    Phosgene (CG), a toxic inhalation and industrial hazard, causes bronchoconstriction, vasoconstriction and associated pathological effects that could be life threatening. Ion channels of the transient receptor potential (TRP) family have been identified to act as specific chemosensory molecules in the respiratory tract in the detection, control of adaptive responses and initiation of detrimental signaling cascades upon exposure to various toxic inhalation hazards (TIH); their activation due to TIH exposure may result in broncho- and vasoconstriction. We studied changes in the regulation of intracellular free Ca(2+) concentration ([Ca(2+)]i) in cultures of human bronchial smooth muscle cells (BSMC) and human pulmonary microvascular endothelial cells (HPMEC) exposed to CG (16ppm, 8min), using an air/liquid interface exposure system. CG increased [Ca(2+)]i (p<0.05) in both cell types, The CG-induced [Ca(2+)]i was blocked (p<0.05) by two types of TRP channel blockers, SKF-96365, a general TRP channel blocker, and RR, a general TRPV (vanilloid type) blocker, in both BSMC and HPMEC. These effects correlate with the in vivo efficacies of these compounds to protect against lung injury and 24h lethality from whole body CG inhalation exposure in mice (8-10ppm×20min). Thus the TRP channel mechanism appears to be a potential target for intervention in CG toxicity.

  1. Deleted in malignant brain tumors 1 protein is a potential biomarker of acute respiratory distress syndrome induced by pneumonia.

    PubMed

    Ren, Shan; Chen, Xia; Jiang, Li; Zhu, Bo; Jiang, Qi; Xi, Xiuming

    2016-09-23

    Acute respiratory distress syndrome (ARDS) is associated with high mortality and morbidity. Early diagnosis and risk stratification in patients with ARDS should improve prognosis. Unfortunately, no clinical biomarkers are available for use in early diagnosis. Quantitative proteomics is a powerful tool for biomarker discovery in cancer, autoimmune diseases, and ARDS. Here, we employed isobaric tags for relative and absolute quantitation (iTRAQ) technology to identify potential biomarkers for early ARDS diagnosis and predict the risk for increased disease severity induced by pneumonia. We collected the bronchoalveolar lavage fluid (BALF) and plasma from ARDS patients with differing degrees of ARDS severity. We identified 338 proteins dysregulated in ARDS through iTRAQ, 18 of which showed significant differences with at least 1.5-fold differential expression in patients with mild or severe ARDS. Differential plasma expression of pulmonary surfactant associated protein A, apolipoprotein A1, and deleted in malignant brain tumors 1 protein (DMBT1) was verified in plasma samples. Our results indicate that DMBT1 can potentially serve as a biomarker for early ARDS diagnosis and disease severity assessment.

  2. Prospective Associations between Emotion Dysregulation and Fear-Potentiated Startle: The Moderating Effect of Respiratory Sinus Arrhythmia

    PubMed Central

    Seligowski, Antonia V.; Lee, Daniel J.; Miron, Lynsey R.; Orcutt, Holly K.; Jovanovic, Tanja; Norrholm, Seth D.

    2016-01-01

    Background: Emotion dysregulation has been implicated in the negative outcomes following trauma exposure. A proposed biomarker of emotion dysregulation, respiratory sinus arrhythmia (RSA), has demonstrated associations with trauma-related phenomena, such as the fear-potentiated startle (FPS) response. The current study aimed to examine the prospective association between emotion dysregulation and RSA and FPS several years following trauma exposure. Methods: Participants were 131 women exposed to a campus mass shooting on February 14, 2008. Pre-shooting emotion dysregulation was assessed in 2006–2008. Startle response, measured by orbicularis oculi electromyography (EMG), and RSA were gathered during an FPS paradigm conducted from 2012 to 2015. Results: No significant associations among emotion dysregulation, RSA, and FPS emerged among the full sample. However, emotion dysregulation predicted FPS during both acquisition (r = 0.40, p < 0.05) and extinction (r = 0.57, p < 0.01) among individuals with high resting RSA. Conclusions: Findings suggest that pre-shooting emotion dysregulation is a potent predictor of FPS several years following potential trauma exposure, and this association varies by RSA level. Results emphasize the importance of examining autonomic regulation in the association between emotion dysregulation and recovery from trauma exposure. PMID:27199871

  3. Application of a multiplex immunoassay for detection of salivary antibody responses to selected potentially waterborne pathogens

    EPA Science Inventory

    Although this work was reviewed by EPA and approved for publication, it may not necessarily reflect official Agency policy. Pathogen-specific antibodies in saliva can be used as bioindicators of recent or ongoing infection. Because collection of saliva is easy and painless, i...

  4. Potential alternative hosts for the pea powdery mildew pathogen Erysiphe trifolii

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Powdery mildew of pea (Pisum sativum) is an important disease in the field and in the greenhouse. The most widely documented powdery mildew pathogen on pea is Erysiphe pisi, but E. baeumleri and E. trifolii have also been reported. We recently showed that E. trifolii is frequently found on pea in th...

  5. Potential of predatory bacteria as biocontrol agents for foodborne and plant pathogens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Foodborne pathogens such as Escherichia coli O157:H7, Salmonella spp., Listeria monocytogenes, Shigella are responsible for frequent occurrences of illnesses and mortality in humans and produce losses. Pre-harvest yield losses and post-harvest decay on minimally processed produce (fruits, vegetables...

  6. Development of two real-time multiplex PCR assays for the detection and quantification of eight key bacterial pathogens in lower respiratory tract infections

    PubMed Central

    Gadsby, N.J.; McHugh, M.P.; Russell, C.D.; Mark, H.; Conway Morris, A.; Laurenson, I.F.; Hill, A.T.; Templeton, K.E.

    2015-01-01

    The frequent lack of a positive and timely microbiological diagnosis in patients with lower respiratory tract infection (LRTI) is an important obstacle to antimicrobial stewardship. Patients are typically prescribed broad-spectrum empirical antibiotics while microbiology results are awaited, but, because these are often slow, negative, or inconclusive, de-escalation to narrow-spectrum agents rarely occurs in clinical practice. The aim of this study was to develop and evaluate two multiplex real-time PCR assays for the sensitive detection and accurate quantification of Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus, Moraxella catarrhalis, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii. We found that all eight bacterial targets could be reliably quantified from sputum specimens down to a concentration of 100 CFUs/reaction (8333 CFUs/mL). Furthermore, all 249 positive control isolates were correctly detected with our assay, demonstrating effectiveness on both reference strains and local clinical isolates. The specificity was 98% on a panel of nearly 100 negative control isolates. Bacterial load was quantified accurately when three bacterial targets were present in mixtures of varying concentrations, mimicking likely clinical scenarios in LRTI. Concordance with culture was 100% for culture-positive sputum specimens, and 90% for bronchoalveolar lavage fluid specimens, and additional culture-negative bacterial infections were detected and quantified. In conclusion, a quantitative molecular test for eight key bacterial causes of LRTI has the potential to provide a more sensitive decision-making tool, closer to the time-point of patient admission than current standard methods. This should facilitate de-escalation from broad-spectrum to narrow-spectrum antibiotics, substantially improving patient management and supporting efforts to curtail inappropriate antibiotic use. PMID:25980353

  7. Impact of Implementing 5 Potentially Better Respiratory Practices on Neonatal Outcomes and Costs

    PubMed Central

    Kalish, Leslie A.; LaPierre, Justine; Welch, Maureen; Porter, Virginia

    2011-01-01

    OBJECTIVE: We implemented 5 potentially better practices to limit mechanical ventilation (MV), supplemental oxygen, and bronchopulmonary dysplasia in newborn infants born before 33 weeks' gestation. METHODS: The methods used in this study included (1) exclusive use of bubble continuous positive airway pressure (bCPAP), (2) provision of bCPAP in the delivery room, (3) strict intubation criteria, (4) strict extubation criteria, and (5) prolonged CPAP to avoid supplemental oxygen. We excluded outborn infants and those with major anomalies and obstetric complications from analysis. RESULTS: Demographics were similar in 61 infants born before and 60 born after implementation. For infants born at 26 to 3267 weeks' gestation, intubation (first 72 hours) decreased from 52% to 11% (P < .0001) and surfactant use decreased from 48% to 14% (P = .0001). In all infants, the mean ± SD fraction of inspired oxygen requirement (first 24 hours) decreased from 0.27 ± 0.08 to 0.24 ± 0.05 (P = .0005), days of oxygen decreased from 23.5 ± 44.5 to 9.3 ± 22.0 (P = .04), and days of MV decreased from 8.8 ± 27.8 to 2.2 ± 6.2 (P = .005). Hypotension decreased from 33% to 15% (P = .03). The percentage of infants with bronchopulmonary dysplasia was 17% before and 8% after (P = .27). Nurse staffing ratios remained unchanged. CONCLUSIONS: Implementation of these potentially better practices reduced the need for MV, surfactant, and supplemental oxygen as well as reduced hypotension among infants born before 33 weeks' gestation without adverse consequences. The costs for equipment and surfactant were lower. PMID:21669893

  8. Molecular-based detection of potentially pathogenic bacteria in membrane bioreactor (MBR) systems treating municipal wastewater: a case study.

    PubMed

    Harb, Moustapha; Hong, Pei-Ying

    2017-02-01

    Although membrane bioreactor (MBR) systems provide better removal of pathogens compared to conventional activated sludge processes, they do not achieve total log removal. The present study examines two MBR systems treating municipal wastewater, one a full-scale MBR plant and the other a lab-scale anaerobic MBR. Both of these systems were operated using microfiltration (MF) polymeric membranes. High-throughput sequencing and digital PCR quantification were utilized to monitor the log removal values (LRVs) of associated pathogenic species and their abundance in the MBR effluents. Results showed that specific removal rates vary widely regardless of the system employed. Each of the two MBR effluents' microbial communities contained genera associated with opportunistic pathogens (e.g., Pseudomonas, Acinetobacter) with a wide range of log reduction values (< 2 to >5.5). Digital PCR further confirmed that these bacterial groups included pathogenic species, in several instances at LRVs different than those for their respective genera. These results were used to evaluate the potential risks associated both with the reuse of the MBR effluents for irrigation purposes and with land application of the activated sludge from the full-scale MBR system.

  9. A framework to gauge the epidemic potential of plant pathogens in environmental reservoirs: the example of kiwifruit canker.

    PubMed

    Bartoli, Claudia; Lamichhane, Jay Ram; Berge, Odile; Guilbaud, Caroline; Varvaro, Leonardo; Balestra, Giorgio M; Vinatzer, Boris A; Morris, Cindy E

    2015-02-01

    New economically important diseases on crops and forest trees emerge recurrently. An understanding of where new pathogenic lines come from and how they evolve is fundamental for the deployment of accurate surveillance methods. We used kiwifruit bacterial canker as a model to assess the importance of potential reservoirs of new pathogenic lineages. The current kiwifruit canker epidemic is at least the fourth outbreak of the disease on kiwifruit caused by Pseudomonas syringae in the mere 50 years in which this crop has been cultivated worldwide, with each outbreak being caused by different genetic lines of the bacterium. Here, we ask whether strains in natural (non-agricultural) environments could cause future epidemics of canker on kiwifruit. To answer this question, we evaluated the pathogenicity, endophytic colonization capacity and competitiveness on kiwifruit of P. syringae strains genetically similar to epidemic strains and originally isolated from aquatic and subalpine habitats. All environmental strains possessing an operon involved in the degradation of aromatic compounds via the catechol pathway grew endophytically and caused symptoms in kiwifruit vascular tissue. Environmental and epidemic strains showed a wide host range, revealing their potential as future pathogens of a variety of hosts. Environmental strains co-existed endophytically with CFBP 7286, an epidemic strain, and shared about 20 virulence genes, but were missing six virulence genes found in all epidemic strains. By identifying the specific gene content in genetic backgrounds similar to known epidemic strains, we developed criteria to assess the epidemic potential and to survey for such strains as a means of forecasting and managing disease emergence.

  10. Research on pathogens at Great Lakes beaches: sampling, influential factors, and potential sources

    USGS Publications Warehouse

    ,

    2013-01-01

    The overall mission of this work is to provide science-based information and methods that will allow beach managers to more accurately make beach closure and advisory decisions, understand the sources and physical processes affecting beach contaminants, and understand how science-based information can be used to mitigate and restore beaches and protect the public. The U.S. Geological Survey (USGS), in collaboration with many Federal, State, and local agencies and universities, has conducted research on beach health issues in the Great Lakes Region for more than a decade. The work consists of four science elements that align with the USGS Beach Health Initiative Mission: real-time assessments of water quality; coastal processes; pathogens and source tracking; and data analysis, interpretation, and communication. The ongoing or completed research for the pathogens and source tracking topic is described in this fact sheet.

  11. Staphylococcus aureus and CCR5: unveiling commonalities in host–pathogen interactions and potential treatment strategies

    PubMed Central

    Alonzo, Francis

    2014-01-01

    Microbes that have acquired the ability to colonize and/or cause disease in humans must be able to both recognize and respond to host defenses to ensure their survival. For commensal microbes, adaptive strategies generally promote a balance between host immune defenses and bacterial maintenance, allowing asymptomatic colonization. Pathogenic microbes, on the other hand, tilt the balance in favor of the microorganism, leading to symptomatic illness and disease. Some microorganisms that are known to be asymptomatic colonizers of humans can cause serious disease upon gaining access to foreign sites and usurping immunological attack. The Gram-positive bacterium Staphylococcus aureus is one such microorganism. This article will address recent advances in our understanding of S. aureus immune evasion with an emphasis on immune cell targeting. The prospects of this targeting in terms of understanding the evolution of S. aureus as a pathogen as well as its implications for future anti-S. aureus therapeutics, will be discussed. PMID:23534355

  12. Saprophytic and Potentially Pathogenic Fusarium Species from Peat Soil in Perak and Pahang

    PubMed Central

    Karim, Nurul Farah Abdul; Mohd, Masratulhawa; Nor, Nik Mohd Izham Mohd; Zakaria, Latiffah

    2016-01-01

    Isolates of Fusarium were discovered in peat soil samples collected from peat swamp forest, waterlogged peat soil, and peat soil from oil palm plantations. Morphological characteristics were used to tentatively identify the isolates, and species confirmation was based on the sequence of translation elongation factor-1α (TEF-1α) and phylogenetic analysis. Based on the closest match of Basic Local Alignment Search Tool (BLAST) searches against the GenBank and Fusarium-ID databases, five Fusarium species were identified, namely F. oxysporum (60%), F. solani (23%), F. proliferatum (14%), F. semitectum (1%), and F. verticillioides (1%). From a neighbour-joining tree of combined TEF-1α and β-tubulin sequences, isolates from the same species were clustered in the same clade, though intraspecies variations were observed from the phylogenetic analysis. The Fusarium species isolated in the present study are soil inhabitants and are widely distributed worldwide. These species can act as saprophytes and decomposers as well as plant pathogens. The presence of Fusarium species in peat soils suggested that peat soils could be a reservoir of plant pathogens, as well-known plant pathogenic species such F. oxysporum, F. solani, F. proliferatum, and F. verticillioides were identified. The results of the present study provide knowledge on the survival and distribution of Fusarium species. PMID:27019679

  13. Antagonistic Potential of Native Trichoderma viride Strain against Potent Tea Fungal Pathogens in North East India

    PubMed Central

    Naglot, A.; Goswami, S.; Rahman, I.; Shrimali, D. D.; Yadav, Kamlesh K.; Gupta, Vikas K.; Rabha, Aprana Jyoti; Gogoi, H. K.; Veer, Vijay

    2015-01-01

    Indigenous strains of Trichoderma species isolated from rhizosphere soils of Tea gardens of Assam, north eastern state of India were assessed for in vitro antagonism against two important tea fungal pathogens namely Pestalotia theae and Fusarium solani. A potent antagonist against both tea pathogenic fungi, designated as SDRLIN1, was selected and identified as Trichoderma viride. The strain also showed substantial antifungal activity against five standard phytopathogenic fungi. Culture filtrate collected from stationary growth phase of the antagonist demonstrated a significantly higher degree of inhibitory activity against all the test fungi, demonstrating the presence of an optimal blend of extracellular antifungal metabolites. Moreover, quantitative enzyme assay of exponential and stationary culture filtrates revealed that the activity of cellulase, β-1,3-glucanase, pectinase, and amylase was highest in the exponential phase, whereas the activity of proteases and chitinase was noted highest in the stationary phase. Morphological changes such as hyphal swelling and distortion were also observed in the fungal pathogen grown on potato dextrose agar containing stationary phase culture filtrate. Moreover, the antifungal activity of the filtrate was significantly reduced but not entirely after heat or proteinase K treatment, demonstrating substantial role of certain unknown thermostable antifungal compound(s) in the inhibitory activity. PMID:26361476

  14. Saprophytic and Potentially Pathogenic Fusarium Species from Peat Soil in Perak and Pahang.

    PubMed

    Karim, Nurul Farah Abdul; Mohd, Masratulhawa; Nor, Nik Mohd Izham Mohd; Zakaria, Latiffah

    2016-02-01

    Isolates of Fusarium were discovered in peat soil samples collected from peat swamp forest, waterlogged peat soil, and peat soil from oil palm plantations. Morphological characteristics were used to tentatively identify the isolates, and species confirmation was based on the sequence of translation elongation factor-1α (TEF-1α) and phylogenetic analysis. Based on the closest match of Basic Local Alignment Search Tool (BLAST) searches against the GenBank and Fusarium-ID databases, five Fusarium species were identified, namely F. oxysporum (60%), F. solani (23%), F. proliferatum (14%), F. semitectum (1%), and F. verticillioides (1%). From a neighbour-joining tree of combined TEF-1α and β-tubulin sequences, isolates from the same species were clustered in the same clade, though intraspecies variations were observed from the phylogenetic analysis. The Fusarium species isolated in the present study are soil inhabitants and are widely distributed worldwide. These species can act as saprophytes and decomposers as well as plant pathogens. The presence of Fusarium species in peat soils suggested that peat soils could be a reservoir of plant pathogens, as well-known plant pathogenic species such F. oxysporum, F. solani, F. proliferatum, and F. verticillioides were identified. The results of the present study provide knowledge on the survival and distribution of Fusarium species.

  15. Antagonistic Potential of Native Trichoderma viride Strain against Potent Tea Fungal Pathogens in North East India.

    PubMed

    Naglot, A; Goswami, S; Rahman, I; Shrimali, D D; Yadav, Kamlesh K; Gupta, Vikas K; Rabha, Aprana Jyoti; Gogoi, H K; Veer, Vijay

    2015-09-01

    Indigenous strains of Trichoderma species isolated from rhizosphere soils of Tea gardens of Assam, north eastern state of India were assessed for in vitro antagonism against two important tea fungal pathogens namely Pestalotia theae and Fusarium solani. A potent antagonist against both tea pathogenic fungi, designated as SDRLIN1, was selected and identified as Trichoderma viride. The strain also showed substantial antifungal activity against five standard phytopathogenic fungi. Culture filtrate collected from stationary growth phase of the antagonist demonstrated a significantly higher degree of inhibitory activity against all the test fungi, demonstrating the presence of an optimal blend of extracellular antifungal metabolites. Moreover, quantitative enzyme assay of exponential and stationary culture filtrates revealed that the activity of cellulase, β-1,3-glucanase, pectinase, and amylase was highest in the exponential phase, whereas the activity of proteases and chitinase was noted highest in the stationary phase. Morphological changes such as hyphal swelling and distortion were also observed in the fungal pathogen grown on potato dextrose agar containing stationary phase culture filtrate. Moreover, the antifungal activity of the filtrate was significantly reduced but not entirely after heat or proteinase K treatment, demonstrating substantial role of certain unknown thermostable antifungal compound(s) in the inhibitory activity.

  16. Immunodominant antigens in Naegleria fowleri excretory--secretory proteins were potential pathogenic factors.

    PubMed

    Kim, Jong-Hyun; Yang, Ae-Hee; Sohn, Hae-Jin; Kim, Daesik; Song, Kyoung-Ju; Shin, Ho-Joon

    2009-11-01

    Naegleria fowleri, a ubiquitous pathogenic free-living amoeba, is the most virulent species and causes primary amoebic meningoencephalitis in laboratory animals and humans. The parasite secretes various inducing molecules as biological responses, which are thought to be involved in pathophysiological and immunological events during infection. To investigate what molecules of N. fowleri excretory-secretory proteins (ESPs) are related with amoebic pathogenicity, N. fowleri ESPs fractionated by two-dimensional electrophoresis were reacted with N. fowleri infection or immune sera. To identify immunodominant ESPs, six major protein spots were selected and analyzed by N-terminal sequencing. Finally, six proteins, 58, 40, 24, 21, 18, and 16 kDa of molecular weight, were partially cloned and matched with reference proteins as follow: 58 kDa of exendin-3 precursor, 40 kDa of secretory lipase, 24 kDa of cathepsin B-like proteases and cysteine protease, 21 kDa of cathepsin B, 18 kDa of peroxiredoxin, and 16 kDa of thrombin receptor, respectively. These results suggest that N. fowleri ESPs contained important proteins, which may play an important role in the pathogenicity of N. fowleri.

  17. The Eurasian otter (Lutra lutra) as a potential host for rickettsial pathogens in southern Italy.

    PubMed

    Santoro, Mario; D'Alessio, Nicola; Cerrone, Anna; Lucibelli, Maria Gabriella; Borriello, Giorgia; Aloise, Gaetano; Auriemma, Clementina; Riccone, Nunzia; Galiero, Giorgio

    2017-01-01

    Canine monocytic ehrlichiosis and rickettsiosis are zoonotic tick-borne diseases of canids caused by the intracellular obligate bacteria Ehrlichia canis and Rickettsia species respectively. In this study, we investigated using standard and real-time PCR and sequencing, the occurrence and molecular characterization of E. canis and Rickettsia species in the Eurasian otter (Lutra lutra) from the southern Italian population. Samples were screened by using molecular assays also for Neospora caninum, Toxoplasma gondii, Clamydophyla spp., Coxiella burnetii, Leishmania spp., Cryptosporidium spp., and Giardia spp. detection, and helminths were studied by traditional methods. Out of six carcasses tested, three were positive for E. canis and co-infection with Rickettsia sp. occurred in one of those. Sequences of the 16S rRNA E. canis gene were identical to each other but differed from most of those previously found in red foxes (Vulpes vulpes) and wolves (Canis lupus) from southern Italy. Helminths included just cystacanths of Sphaerirostris spp. from the intestine of two Eurasian otters and the nematode Angiostrongylus vasorum from the lungs of a single Eurasian otter. None of the samples was positive for the other investigated selected pathogens. This study is the first report on the evidence of infection by rickettsial pathogens in the Eurasian otter. The present result prompts some inquiries into the pathogenic role of those bacteria for the isolated sub-populations of the endangered Eurasian otter in southern Italy.

  18. The Eurasian otter (Lutra lutra) as a potential host for rickettsial pathogens in southern Italy

    PubMed Central

    D’Alessio, Nicola; Cerrone, Anna; Lucibelli, Maria Gabriella; Borriello, Giorgia; Aloise, Gaetano; Auriemma, Clementina; Riccone, Nunzia; Galiero, Giorgio

    2017-01-01

    Canine monocytic ehrlichiosis and rickettsiosis are zoonotic tick-borne diseases of canids caused by the intracellular obligate bacteria Ehrlichia canis and Rickettsia species respectively. In this study, we investigated using standard and real-time PCR and sequencing, the occurrence and molecular characterization of E. canis and Rickettsia species in the Eurasian otter (Lutra lutra) from the southern Italian population. Samples were screened by using molecular assays also for Neospora caninum, Toxoplasma gondii, Clamydophyla spp., Coxiella burnetii, Leishmania spp., Cryptosporidium spp., and Giardia spp. detection, and helminths were studied by traditional methods. Out of six carcasses tested, three were positive for E. canis and co-infection with Rickettsia sp. occurred in one of those. Sequences of the 16S rRNA E. canis gene were identical to each other but differed from most of those previously found in red foxes (Vulpes vulpes) and wolves (Canis lupus) from southern Italy. Helminths included just cystacanths of Sphaerirostris spp. from the intestine of two Eurasian otters and the nematode Angiostrongylus vasorum from the lungs of a single Eurasian otter. None of the samples was positive for the other investigated selected pathogens. This study is the first report on the evidence of infection by rickettsial pathogens in the Eurasian otter. The present result prompts some inquiries into the pathogenic role of those bacteria for the isolated sub-populations of the endangered Eurasian otter in southern Italy. PMID:28267780

  19. A Novel Bacterial Pathogen of Biomphalaria glabrata: A Potential Weapon for Schistosomiasis Control?

    PubMed Central

    Duval, David; Galinier, Richard; Mouahid, Gabriel; Toulza, Eve; Allienne, Jean François; Portela, Julien; Calvayrac, Christophe; Rognon, Anne; Arancibia, Nathalie; Mitta, Guillaume; Théron, André; Gourbal, Benjamin

    2015-01-01

    Background Schistosomiasis is the second-most widespread tropical parasitic disease after malaria. Various research strategies and treatment programs for achieving the objective of eradicating schistosomiasis within a decade have been recommended and supported by the World Health Organization. One of these approaches is based on the control of snail vectors in endemic areas. Previous field studies have shown that competitor or predator introduction can reduce snail numbers, but no systematic investigation has ever been conducted to identify snail microbial pathogens and evaluate their molluscicidal effects. Methodology/Principal findings In populations of Biomphalaria glabrata snails experiencing high mortalities, white nodules were visible on snail bodies. Infectious agents were isolated from such nodules. Only one type of bacteria, identified as a new species of Paenibacillus named Candidatus Paenibacillus glabratella, was found, and was shown to be closely related to P. alvei through 16S and Rpob DNA analysis. Histopathological examination showed extensive bacterial infiltration leading to overall tissue disorganization. Exposure of healthy snails to Paenibacillus-infected snails caused massive mortality. Moreover, eggs laid by infected snails were also infected, decreasing hatching but without apparent effects on spawning. Embryonic lethality was correlated with the presence of pathogenic bacteria in eggs. Conclusions/Significance This is the first account of a novel Paenibacillus strain, Ca. Paenibacillus glabratella, as a snail microbial pathogen. Since this strain affects both adult and embryonic stages and causes significant mortality, it may hold promise as a biocontrol agent to limit schistosomiasis transmission in the field. PMID:25719489

  20. The Key Events Dose-Response Framework: Its Potential for Application to Foodborne Pathogenic Microorganisms

    PubMed Central

    BUCHANAN, ROBERT L.; HAVELAAR, ARIE H.; SMITH, MARY ALICE; WHITING, RICHARD C.; JULIEN, ELIZABETH

    2009-01-01

    The Key Events Dose-Response Framework (KEDRF) is an analytical approach that facilitates the use of currently available data to gain insight regarding dose-response relationships. The use of the KEDRF also helps identify critical knowledge gaps that once filled, will reduce reliance on assumptions. The present study considers how the KEDRF might be applied to pathogenic microorganisms, using fetal listeriosis resulting from maternal ingestion of food contaminated with L. monocytogenes as an initial example. Major biological events along the pathway between food ingestion and the endpoint of concern are systematically considered with regard to dose (i.e., number of organisms), pathogen factors (e.g., virulence), and protective host mechanisms (e.g., immune response or other homeostatic mechanisms). It is concluded that the KEDRF provides a useful structure for systematically evaluating the complex array of host and pathogen factors that influence the dose-response relationship. In particular, the KEDRF supports efforts to specify and quantify the sources of variability, a prerequisite to strengthening the scientific basis for food safety decision making. PMID:19690997

  1. Respiratory allergenic potential of plant-derived proteins: Understanding the relationship between exposure and potency for risk assessments.

    PubMed

    Blackburn, Karen; N'jai, Alhaji U; Dearman, Rebecca J; Kimber, Ian; Gerberick, G Frank

    2015-01-01

    Botanical ingredients (ingredients derived from plants) are finding increasing application in personal care products and the public perceives these ingredients to be safe. However, some proteins in botanicals have the potential to cause immediate-type (IgE-mediated) respiratory allergic reactions. Although reports of such reactions are uncommon, when they do occur, they can be severe. Experience with soap containing wheat proteins illustrated that under certain specific conditions, consumers may be affected. Establishing safe exposure levels for botanical proteins has been challenging. Industrial enzymes provide a rich reference dataset based on their historical association with allergic reactions among workers, which includes robust dose-response information. In the absence of similar data on the potency of plant proteins, a conservative default approach has historically been applied based on information derived from allergenic enzymes. In this article we review the historical default approach and dataset for setting limits for plant proteins in botanical ingredients based on analogy to industrial enzymes followed by a synthesis of literature data on allergic reactions following inhalation exposure to plant-derived proteins. The aim is to share relevant background information and display the relationship between exposure and potency as a first step in the development of a strategy for the development of an improved approach to support the risk assessment of plant-derived proteins.

  2. Fungal diversity and presence of potentially pathogenic fungi in a hospital hot water system treated with on-site monochloramine.

    PubMed

    Ma, Xiao; Baron, Julianne L; Vikram, Amit; Stout, Janet E; Bibby, Kyle

    2015-03-15

    Currently, our knowledge of fungal ecology in engineered drinking water systems is limited, despite the potential for these systems to serve as a reservoir for opportunistic pathogens. In this study, hot water samples were collected both prior to and following the addition of monochloramine as an on-site disinfectant in a hospital hot water system. Fungal ecology was then analyzed by high throughput sequencing of the fungal ITS1 region. The results demonstrate that the genera Penicillium, Aspergillus, Peniophora, Cladosporium and Rhodosporidium comprised the core fungal biome of the hospital hot water system. Penicillium dominated the fungal community with an average relative abundance of 88.89% (±6.37%). ITS1 sequences of fungal genera containing potential pathogens such as Aspergillus, Candida, and Fusarium were also detected in this study. No significant change in fungal community structure was observed before and after the initiation of on-site monochloramine water treatment. This work represents the first report of the effects of on-site secondary water disinfection on fungal ecology in premise plumbing system, and demonstrates the necessity of considering opportunistic fungal pathogens during the evaluation of secondary premise plumbing disinfection systems.

  3. Non-tuberculous Mycobacteria in South African Wildlife: Neglected Pathogens and Potential Impediments for Bovine Tuberculosis Diagnosis

    PubMed Central

    Gcebe, Nomakorinte; Hlokwe, Tiny M.

    2017-01-01

    Non-tuberculous mycobacteria (NTM) are not only emerging and opportunistic pathogens of both humans and animals, but from a veterinary point of view some species induce cross-reactive immune responses that hamper the diagnosis of bovine tuberculosis (bTB) in both livestock and wildlife. Little information is available about NTM species circulating in wildlife species of South Africa. In this study, we determined the diversity of NTM isolated from wildlife species from South Africa as well as Botswana. Thirty known NTM species and subspecies, as well as unidentified NTM, and NTM closely related to Mycobacterium goodii/Mycobacterium smegmatis were identified from 102 isolates cultured between the years 1998 and 2010, using a combination of molecular assays viz PCR and sequencing of different Mycobacterial house-keeping genes as well as single nucleotide polymorphism (SNP) analysis. The NTM identified in this study include the following species which were isolated from tissue with tuberculosis- like lesions in the absence of Mycobacterium tuberculosis complex (MTBC) implying their potential role as pathogens of animals: Mycobacterium abscessus subsp. bolletii, Mycobacterium gastri, Mycobacterium species closely related to Mycobacterium goodii/Mycobacterium smegmatis, Mycobacterium brasiliensis, Mycobacterium sinense JMD 601, Mycobacterium avium subsp. avium, Mycobacterium sp. GR-2007, Mycobacterium bouchedurhonense, and Mycobacterium septicum/M. peregrinum. Mycobaterium brasiliensis, Mycobacterium gastri, Mycobacterium sp. GR-2007, and a potential novel Mycobacterium species closely related to Mycobacterium goodii were found for the first time in this study to be potential pathogens of animals. Mycobacterium simiae was isolated from a sample originating from a tuberculin skin test positive reactor, demonstrating its potential to elicit inappropriate immune responses in animals that may interfere with diagnosis of tuberculosis by immunology. Mycobacterium abscessus

  4. Non-tuberculous Mycobacteria in South African Wildlife: Neglected Pathogens and Potential Impediments for Bovine Tuberculosis Diagnosis.

    PubMed

    Gcebe, Nomakorinte; Hlokwe, Tiny M

    2017-01-01

    Non-tuberculous mycobacteria (NTM) are not only emerging and opportunistic pathogens of both humans and animals, but from a veterinary point of view some species induce cross-reactive immune responses that hamper the diagnosis of bovine tuberculosis (bTB) in both livestock and wildlife. Little information is available about NTM species circulating in wildlife species of South Africa. In this study, we determined the diversity of NTM isolated from wildlife species from South Africa as well as Botswana. Thirty known NTM species and subspecies, as well as unidentified NTM, and NTM closely related to Mycobacterium goodii/Mycobacterium smegmatis were identified from 102 isolates cultured between the years 1998 and 2010, using a combination of molecular assays viz PCR and sequencing of different Mycobacterial house-keeping genes as well as single nucleotide polymorphism (SNP) analysis. The NTM identified in this study include the following species which were isolated from tissue with tuberculosis- like lesions in the absence of Mycobacterium tuberculosis complex (MTBC) implying their potential role as pathogens of animals: Mycobacterium abscessus subsp. bolletii, Mycobacterium gastri, Mycobacterium species closely related to Mycobacterium goodii/Mycobacterium smegmatis, Mycobacterium brasiliensis, Mycobacterium sinense JMD 601, Mycobacterium avium subsp. avium, Mycobacterium sp. GR-2007, Mycobacterium bouchedurhonense, and Mycobacterium septicum/M. peregrinum. Mycobaterium brasiliensis, Mycobacterium gastri, Mycobacterium sp. GR-2007, and a potential novel Mycobacterium species closely related to Mycobacterium goodii were found for the first time in this study to be potential pathogens of animals. Mycobacterium simiae was isolated from a sample originating from a tuberculin skin test positive reactor, demonstrating its potential to elicit inappropriate immune responses in animals that may interfere with diagnosis of tuberculosis by immunology. Mycobacterium abscessus

  5. Burden of acute respiratory disease of epidemic and pandemic potential in the WHO Eastern Mediterranean Region: A literature review.

    PubMed

    Abubakar, A; Malik, M; Pebody, R G; Elkholy, A A; Khan, W; Bellos, A; Mala, P

    2016-10-02

    There are gaps in the knowledge about the burden of severe respiratory disease in the Eastern Mediterranean Region (EMR). This literature review was therefore conducted to describe the burden of epidemicand pandemic-prone acute respiratory infections (ARI) in the Region which may help in the development of evidence-based disease prevention and control policies. Relevant published and unpublished reports were identified from searches of various databases; 83 documents fulfilled the search criteria. The infections identified included: ARI, avian influenza A(H5N1), influenza A(H1N1)pdm09 and Middle East respiratory syndrome coronavirus (MERS-CoV) infection. Pneumonia and ARIs were leading causes of disease and death in the Region. Influenza A(H1N1) was an important cause of morbidity during the 2009 pandemic. This review provides a descriptive summary of the burden of acute respiratory diseases in the Region, but there still remains a lack of necessary data.

  6. Adaptive Potential of Maritime Pine (Pinus pinaster) Populations to the Emerging Pitch Canker Pathogen, Fusarium circinatum

    PubMed Central

    Elvira-Recuenco, Margarita; Iturritxa, Eugenia; Majada, Juan; Alia, Ricardo; Raposo, Rosa

    2014-01-01

    There is a concern on how emerging pests and diseases will affect the distribution range and adaptability of their host species, especially due to different conditions derived from climate change and growing globalization. Fusarium circinatum, which causes pitch canker disease in Pinus species, is an exotic pathogen of recent introduction in Spain that threatens its maritime pine (P. pinaster) stands. To predict the impact this disease will have on the species, we examine host resistance traits and their genetic architecture. Resistance phenotyping was done in a clonal provenance/progeny trial, using three-year-old cuttings artificially inoculated with the pathogen and maintained under controlled environmental conditions. A total number of 670 ramets were assessed, distributed in 10 populations, with a total of 47 families, 2 to 5 half-sibs per family, and 3–7 ramets per clone. High genetic variation was found at the three hierarchical levels studied: population, family and clone, being both additive and non-additive effects important. Narrow-sense and broad-sense heritability estimates were relatively high, with respective values of 0.43–0.58 and 0.51–0.8, depending on the resistance traits measured (lesion length, lesion length rate, time to wilting, and survival). These values suggest the species' high capacity of evolutionary response to the F. circinatum pathogen. A population originated in Northern Spain was the most resistant, while another from Morocco was the most susceptible. The total number of plants that did not show lesion development or presented a small lesion (length<30 mm) was 224 out of 670, indicating a high proportion of resistant trees in the offspring within the analyzed populations. We found large differences among populations and considerable genetic variation within populations, which should allow, through natural or artificial selection, the successful adaptation of maritime pine to pitch canker disease. PMID:25500822

  7. Adaptive potential of maritime pine (Pinus pinaster) populations to the emerging pitch canker pathogen, Fusarium circinatum.

    PubMed

    Elvira-Recuenco, Margarita; Iturritxa, Eugenia; Majada, Juan; Alia, Ricardo; Raposo, Rosa

    2014-01-01

    There is a concern on how emerging pests and diseases will affect the distribution range and adaptability of their host species, especially due to different conditions derived from climate change and growing globalization. Fusarium circinatum, which causes pitch canker disease in Pinus species, is an exotic pathogen of recent introduction in Spain that threatens its maritime pine (P. pinaster) stands. To predict the impact this disease will have on the species, we examine host resistance traits and their genetic architecture. Resistance phenotyping was done in a clonal provenance/progeny trial, using three-year-old cuttings artificially inoculated with the pathogen and maintained under controlled environmental conditions. A total number of 670 ramets were assessed, distributed in 10 populations, with a total of 47 families, 2 to 5 half-sibs per family, and 3-7 ramets per clone. High genetic variation was found at the three hierarchical levels studied: population, family and clone, being both additive and non-additive effects important. Narrow-sense and broad-sense heritability estimates were relatively high, with respective values of 0.43-0.58 and 0.51-0.8, depending on the resistance traits measured (lesion length, lesion length rate, time to wilting, and survival). These values suggest the species' high capacity of evolutionary response to the F. circinatum pathogen. A population originated in Northern Spain was the most resistant, while another from Morocco was the most susceptible. The total number of plants that did not show lesion development or presented a small lesion (length<30 mm) was 224 out of 670, indicating a high proportion of resistant trees in the offspring within the analyzed populations. We found large differences among populations and considerable genetic variation within populations, which should allow, through natural or artificial selection, the successful adaptation of maritime pine to pitch canker disease.

  8. Antibacterial peptide nisin: a potential role in the inhibition of oral pathogenic bacteria.

    PubMed

    Tong, Zhongchun; Ni, Longxing; Ling, Junqi

    2014-10-01

    Although the antimicrobial peptide nisin has been extensively studied in the food industry for decades, its application in the oral cavity remains to develop and evaluate its feasibility in treating oral common diseases. Nisin is an odorless, colorless, tasteless substance with low toxicity and with antibacterial activities against Gram-positive bacteria. These biologic properties may establish its use in promising products for oral diseases. This article summarizes the antibacterial efficiency of nisin against pathogenic bacteria related to dental caries and root canal infection and discusses the combination of nisin and common oral drugs.

  9. Balamuthia mandrillaris in South America: an emerging potential hidden pathogen in Perú.

    PubMed

    Cabello-Vílchez, Alfonso M; Rodríguez-Zaragoza, Salvador; Piñero, José; Valladares, Basilio; Lorenzo-Morales, Jacob

    2014-11-01

    Balamuthia mandrillaris is a free living amoeba that can be isolated from soil. It is an emerging pathogen causing skin lesions as well as CNS involvement with a fatal outcome if untreated. Further, infections can sometimes can also appear in peripheral areas such as extremities (usually knee), or trunk. Moreover, it often progresses to an infiltrative lesion that occasionally becomes ulcerated. In countries like Peru, a skin lesion will precede other symptoms. This primary cutaneous lesion can be present for weeks or even months. However, the appearance of neurological disease predicts a poor prognosis. Diagnosis requires a high level of suspicion.

  10. Experimental vaccines against potentially pandemic and highly pathogenic avian influenza viruses

    PubMed Central

    Mooney, Alaina J; Tompkins, S Mark

    2013-01-01

    Influenza A viruses continue to emerge and re-emerge, causing outbreaks, epidemics and occasionally pandemics. While the influenza vaccines licensed for public use are generally effective against seasonal influenza, issues arise with production, immunogenicity, and efficacy in the case of vaccines against pandemic and emerging influenza viruses, and highly pathogenic avian influenza virus in particular. Thus, there is need of improved influenza vaccines and vaccination strategies. This review discusses advances in alternative influenza vaccines, touching briefly on licensed vaccines and vaccine antigens; then reviewing recombinant subunit vaccines, virus-like particle vaccines and DNA vaccines, with the main focus on virus-vectored vaccine approaches. PMID:23440999

  11. Calpains: Potential Targets for Alternative Chemotherapeutic Intervention Against Human Pathogenic Trypanosomatids

    PubMed Central

    M.H, Branquinha; F.A, Marinho; L.S, Sangenito; S.S.C, Oliveira; K.C, Gonçalves; V, Ennes-Vidal; C.M, d’Avila-Levy; A.L.S, Santos

    2013-01-01

    The treatment for both leishmaniasis and trypanosomiasis, which are severe human infections caused by trypanosomatids belonging to Leishmania and Trypanosoma genera, respectively, is extremely limited because of concerns of toxicity and efficacy with the available anti-protozoan drugs, as well as the emergence of drug resistance. Consequently, the urgency for the discovery of new trypanosomatid targets and novel bioactive compounds is particularly necessary. In this context, the investigation of changes in parasite gene expression between drug resistant/sensitive strains and in the up-regulation of virulence-related genes in infective forms has brought to the fore the involvement of calpain-like proteins in several crucial pathophysiological processes performed by trypanosomatids. These studies were encouraged by the publication of the complete genome sequences of three human pathogenic trypanosomatids, Trypanosoma brucei, Trypanosoma cruzi and Leishmania major, which allowed in silico analyses that in turn directed the identification of numerous genes with interesting chemotherapeutic characteristics, including a large family of calpain-related proteins, in which to date 23 genes were assigned as calpains in T. brucei, 40 in T. cruzi and 33 in L. braziliensis. In the present review, we intend to add to these biochemical/biological reports the investigations performed upon the inhibitory capability of calpain inhibitors against human pathogenic trypanosomatids. PMID:23899207

  12. The Water Cycle, a Potential Source of the Bacterial Pathogen Bacillus cereus

    PubMed Central

    Brillard, Julien; Dupont, Christian M. S.; Berge, Odile; Dargaignaratz, Claire; Oriol-Gagnier, Stéphanie; Doussan, Claude; Broussolle, Véronique; Gillon, Marina; Clavel, Thierry; Bérard, Annette

    2015-01-01

    The behaviour of the sporulating soil-dwelling Bacillus cereus sensu lato (B. cereus sl) which includes foodborne pathogenic strains has been extensively studied in relation to its various animal hosts. The aim of this environmental study was to investigate the water compartments (rain and soil water, as well as groundwater) closely linked to the primary B. cereus sl reservoir, for which available data are limited. B. cereus sl was present, primarily as spores, in all of the tested compartments of an agricultural site, including water from rain to groundwater through soil. During rain events, leachates collected after transfer through the soil eventually reached the groundwater and were loaded with B. cereus sl. In groundwater samples, newly introduced spores of a B. cereus model strain were able to germinate, and vegetative cells arising from this event were detected for up to 50 days. This first B. cereus sl investigation in the various types of interrelated environments suggests that the consideration of the aquatic compartment linked to soil and to climatic events should provide a better understanding of B. cereus sl ecology and thus be relevant for a more accurate risk assessment of food poisoning caused by B. cereus sl pathogenic strains. PMID:25918712

  13. Discovering potential sources of emerging pathogens: South America is a reservoir of generalist avian blood parasites.

    PubMed

    Moens, Michaël A J; Pérez-Tris, Javier

    2016-01-01

    Generalist pathogens are capable of infecting a wide range of host species, and may pose serious disease emergence threats if accidentally moved outside their native areas. To date little effort has been devoted to identifying geographic areas that may act as reservoirs of generalist pathogens. According to current theory, where host diversity is high, parasite specialisation in one host species may be penalised by reduced host availability, while generalist parasites may benefit from the exploitation of various host species. Therefore natural selection could favor generalist parasites where host diversity is high. Here we explored if, in a highly diverse bird community in Ecuador, a generalist strategy is promoted among local Haemoproteus and Plasmodium blood-borne parasites compared with similar parasite communities throughout the world. We reconstructed the phylogenetic relationships of every parasite lineage in order to understand the evolution of host specificity in this megadiverse area. We found high levels of host generalisation for both parasite genera, and the mean host range of the Haemoproteus community in Ecuador was significantly higher than other parasite communities in other areas outside the Neotropics. Generalist Haemoproteus parasites in this bird community had diverse phylogenetic ancestry, were closely related to specialist parasites and were apparently endemic to the Amazon, showing that different parasites have independently evolved into host generalists in this region. Finally we show that Haemoproteus communities in Ecuador and South America are more generalist than in temperate areas, making this continent a hotspot of generalist Haemoproteus parasites for wild birds.

  14. The Water Cycle, a Potential Source of the Bacterial Pathogen Bacillus cereus.

    PubMed

    Brillard, Julien; Dupont, Christian M S; Berge, Odile; Dargaignaratz, Claire; Oriol-Gagnier, Stéphanie; Doussan, Claude; Broussolle, Véronique; Gillon, Marina; Clavel, Thierry; Bérard, Annette

    2015-01-01

    The behaviour of the sporulating soil-dwelling Bacillus cereus sensu lato (B. cereus sl) which includes foodborne pathogenic strains has been extensively studied in relation to its various animal hosts. The aim of this environmental study was to investigate the water compartments (rain and soil water, as well as groundwater) closely linked to the primary B. cereus sl reservoir, for which available data are limited. B. cereus sl was present, primarily as spores, in all of the tested compartments of an agricultural site, including water from rain to groundwater through soil. During rain events, leachates collected after transfer through the soil eventually reached the groundwater and were loaded with B. cereus sl. In groundwater samples, newly introduced spores of a B. cereus model strain were able to germinate, and vegetative cells arising from this event were detected for up to 50 days. This first B. cereus sl investigation in the various types of interrelated environments suggests that the consideration of the aquatic compartment linked to soil and to climatic events should provide a better understanding of B. cereus sl ecology and thus be relevant for a more accurate risk assessment of food poisoning caused by B. cereus sl pathogenic strains.

  15. Pathogenic potential of Escherichia coli clinical strains from orthopedic implant infections towards human osteoblastic cells

    PubMed Central

    Crémet, Lise; Broquet, Alexis; Brulin, Bénédicte; Jacqueline, Cédric; Dauvergne, Sandie; Brion, Régis; Asehnoune, Karim; Corvec, Stéphane; Heymann, Dominique; Caroff, Nathalie

    2015-01-01

    Escherichia coli is one of the first causes of Gram-negative orthopedic implant infections (OII), but little is known about the pathogenicity of this species in such infections that are increasing due to the ageing of the population. We report how this pathogen interacts with human osteoblastic MG-63 cells in vitro, by comparing 20 OII E. coli strains to two Staphylococcus aureus and two Pseudomonas aeruginosa strains. LDH release assay revealed that 6/20 (30%) OII E. coli induced MG-63 cell lysis whereas none of the four control strains was cytotoxic after 4 h of coculture. This high cytotoxicity was associated with hemolytic properties and linked to hlyA gene expression. We further showed by gentamicin protection assay and confocal microscopy that the non-cytotoxic E. coli were not able to invade MG-63 cells unlike S. aureus strains (internalization rate <0.01% for the non-cytotoxic E. coli versus 8.88 ± 2.31% and 4.60 ± 0.42% for both S. aureus). The non-cytotoxic E. coli also demonstrated low adherence rates (<7%), the most adherent E. coli eliciting higher IL-6 and TNF-α mRNA expression in the osteoblastic cells. Either highly cytotoxic or slightly invasive OII E. coli do not show the same infection strategies as S. aureus towards osteoblasts. PMID:26333570

  16. Felis catus gammaherpesvirus 1; a widely endemic potential pathogen of domestic cats.

    PubMed

    Beatty, Julia A; Troyer, Ryan M; Carver, Scott; Barrs, Vanessa R; Espinasse, Fanny; Conradi, Oliver; Stutzman-Rodriguez, Kathryn; Chan, Cathy C; Tasker, Séverine; Lappin, Michael R; VandeWoude, Sue

    2014-07-01

    Felis catus gammaherpesvirus 1 (FcaGHV1), recently discovered in the USA, was detected in domestic cats in Australia (11.4%, 95% confidence interval 5.9-19.1, n=110) and Singapore (9.6%, 95% confidence interval 5.9-14.6, n=176) using qPCR. FcaGHV1 qPCR positive cats were 2.8 times more likely to be sick than healthy. Risk factors for FcaGHV1 detection included being male, increasing age and coinfection with pathogenic retroviruses, feline immunodeficiency virus (FIV) or feline leukaemia virus. FcaGHV1 DNA was detected in multiple tissues from infected cats with consistently high virus loads in the small intestine. FcaGHV1 viral load was significantly higher in FIV-infected cats compared with matched controls, mimicking increased Epstein-Barr virus loads in human immunodeficiency virus-infected humans. FcaGHV1 is endemic in distant geographic regions and is associated with being sick and with coinfections. Horizontal transmission of FcaGHV1 is supported, with biting being a plausible route. A pathogenic role for FcaGHV1 in domestic cats is supported.

  17. Both Nsp1β and Nsp11 are responsible for differential TNF-α production induced by porcine reproductive and respiratory syndrome virus strains with different pathogenicity in vitro.

    PubMed

    He, Qing; Li, Yan; Zhou, Lei; Ge, Xinna; Guo, Xin; Yang, Hanchun

    2015-04-02

    Porcine reproductive and respiratory syndrome virus (PRRSV) has been recognized to be one of the most important pathogens severely affecting global swine industry. An increasingly number of studies have paid much attention to the diverse roles of its nonstructural proteins (Nsps) in regulating the innate immune response of host upon PRRSV infection. In the present study, we first discovered that highly pathogenic PRRSV (HP-PRRSV) and low pathogenic PRRSV (LP-PRRSV) infection exhibited a differential TNF-α expression in pulmonary alveolar macrophages (PAMs), showing that HP-PRRSV infection induces lower TNF-α production at protein level in PAMs, compared with LP-PRRSV. Next, HP-PRRSV was confirmed to strongly suppress TNF-α production by inhibiting ERK signaling pathway. Finally, both Nsp1β and Nsp11 were demonstrated to be responsible for the inhibitory effect on TNF-α production induced by HP-PRRSV and the differential TNF-α production in PAMs. These findings contribute to the understanding of the pathogenesis of the Chinese HP-PRRSV.

  18. Respiratory acidosis

    MedlinePlus

    ... Names Ventilatory failure; Respiratory failure; Acidosis - respiratory Images Respiratory system References Effros RM, Swenson ER. Acid-base balance. In: Broaddus VC, Mason RJ, Ernst JD, et al, eds. Murray and Nadel's Textbook of Respiratory Medicine . 6th ed. Philadelphia, PA: Elsevier Saunders; 2016: ...

  19. Acute lower respiratory infections in ≥5 year -old hospitalized patients in Cambodia, a low-income tropical country: clinical characteristics and pathogenic etiology

    PubMed Central

    2013-01-01

    Background Few data exist on viral and bacterial etiology of acute lower respiratory infections (ALRI) in ≥5 year –old persons in the tropics. Methods We conducted active surveillance of community-acquired ALRI in two hospitals in Cambodia, a low-income tropical country. Patients were tested for acid-fast bacilli (AFB) by direct sputum examination, other bacteria by blood and/or sputum cultures, and respiratory viruses using molecular techniques on nasopharyngeal/throat swabs. Pulmonologists reviewed clinical/laboratory data and interpreted chest X-rays (CXR) to confirm ALRI. Results Between April 2007 - December 2009, 1,904 patients aged ≥5 years were admitted with acute pneumonia (50.4%), lung sequelae-associated ALRI (24.3%), isolated pleural effusions (8.9%) or normal CXR-related ALRI (17.1%); 61 (3.2%) died during hospitalization. The two former diagnoses were predominantly due to bacterial etiologies while viral detection was more frequent in the two latter diagnoses. AFB-positive accounted for 25.6% of acute pneumonia. Of the positive cultures (16.8%), abscess-prone Gram-negative bacteria (39.6%) and Haemophilus influenzae (38.0%) were most frequent, followed by Streptococcus pneumoniae (17.7%). Of the identified viruses, the three most common viruses included rhinoviruses (49.5%), respiratory syncytial virus (17.7%) and influenza viruses (12.1%) regardless of the diagnostic groups. Wheezing was associated with viral identification (31.9% vs. 13.8%, p < 0.001) independent of age and time-to-admission. Conclusions High frequency of H. influenzae and S. pneumoniae infections support the need for introduction of the respective vaccines in the national immunization program. Tuberculosis was frequent in patients with acute pneumonia, requiring further investigation. The relationship between respiratory viruses and wheezing merits further studies. PMID:23432906

  20. Potential of the marine sponge Hymeniacidon perleve as a bioremediator of pathogenic bacteria in integrated aquaculture ecosystems.

    PubMed

    Fu, Wantao; Sun, Liming; Zhang, Xichang; Zhang, Wei

    2006-04-20

    The aim of this article is to investigate the potential of using sponges as a bioremediator to remove pathogenic bacteria in integrated aquaculture ecosystems. Using the inter-tidal marine sponge Hymeniacidon perleve as a model system, the ability of removing the most common pathogens Escherichia coli and Vibrio anguillarum II in aquaculture waters was screened in laboratory tests. In sterilized natural seawater (SNSW) supplemented with E. coli at (7.0-8.3) x 10(6) cells/mL, H. perleve can remove an average 96% of E.coli within 10.5 h at a filter rate of ca. (7.53-8.03) x 10(7) cells/h x g of fresh sponge in two independent tests. Despite the removal efficiency and filter rate are similar; the clearance rates (CR) vary significantly among individual sponge specimens and between two batches. For the tests on V. anguillarum II in SNSW, about 1.5 g fresh sponges can keep the pathogen growth under control at a lower initial density 3.6 x 10(4) cells/mL of 200 mL water volume. Further tests were done for 24 h using about 12 g fresh sponge in 2-L actual seawater collected from two aquaculture sites that have ca. eightfold difference in pathogenic bacteria load. The concentrations of E. coli, Vibrio, and total bacteria at 24 h in treatment groups were markedly lower, at about 0.9%, 6.2%-34.5%, and 13.7%-22.5%, respectively, of those in the control. Using a fluoresce stain 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate, E. coli, and V. anguillarum II cells were stained and fed to sponges in two independent tests. The confocal microscope observation confirmed that the sponges filtering-retained and digested these bacteria by phagocytosis.

  1. Exposure to minimally processed pear and melon during shelf life could modify the pathogenic potential of Listeria monocytogenes.

    PubMed

    Colás-Medà, Pilar; Viñas, Inmaculada; Oliveira, Márcia; Anguera, Marina; Serrano, Jose C E; Abadias, Maribel

    2017-04-01

    Survival and virulence of foodborne pathogens can be influenced by environmental factors such as the intrinsic properties of food as well as the extrinsic properties that contribute to food shelf life (e.g., temperature and gas atmosphere). The direct contribution of food matrix characteristics on the survival of L. monocytogenes during fresh-cut fruit shelf life is not very well understood. In addition, the gastrointestinal tract is the primary route of listeriosis infection and penetration of the intestinal epithelial cell barrier is the first step in the infection process. Hence, the pathogenic potential of L. monocytogenes, measured as the capability for the organism to survive a simulated gastrointestinal tract and the proportion of cells able to subsequently adhere to and invade differentiated Caco-2 cells, subjected to fresh-cut pear and melon shelf life, was investigated. Samples were inoculated, stored at 10 °C for 7 days and evaluated after inoculation and again after 2 and 7 days of storage. A decrease in L. monocytogenes' capacity to survive a simulated gastrointestinal tract was observed with increasing storage time, regardless of the fruit matrix evaluated. Furthermore, L. monocytogenes placed on fresh-cut pear and melon was subjected to an attachment and invasion assay after crossing the simulated gastrointestinal tract. After inoculation, pathogen on fresh-cut pear showed 5-fold more capacity to adhere to Caco-2 cells than pathogen on fresh-cut melon. After 2 days of storage, L. monocytogenes grown on fresh-cut melon showed similar adhesive capacity (1.11%) than cells grown on pear (1.83%), but cells grown on melon had the higher invasive capacity (0.0093%). We can conclude that minimally processed melon could represent a more important hazard than pear under the studied shelf life.

  2. Enteroccocus pallens as a potential novel human pathogen: three cases of spontaneous bacterial peritonitis

    PubMed Central

    Longtin, Yves; Domingo, Marc-Christian; Massé, Cynthia; Bernatchez, Harold; Gaudreau, Christiane; Tremblay, Cécile

    2016-01-01

    Introduction: Enterococcus pallens is one of the four yellow-pigmented members of the genus Enterococcus. To date, a single report of E. pallens isolated from a human sample has been published. Case presentation: We report three cases of E. pallens spontaneous bacterial peritonitis in patients with liver cirrhosis that all occurred in Quebec, Canada. Ascitic fluid analysis revealed the presence of E. pallens in culture. Identification was made by classical biochemical testing and MALDI-TOF MS, as well as 16S rRNA and elongation factor (tuf) gene sequencing. Two of the three patients recovered after antimicrobial treatment. Conclusion: This report identifies E. pallens as a novel human pathogen that appears to possess particular but as-yet unidentified virulence factors that favour the development of peritoneal fluid infections, as previously reported for other Enterococcus species. Clinical microbiologist should be aware of this micro-organism which can be identified by phenotypic and molecular methods. PMID:28348751

  3. [Serologic studies of domestic cats for potential human pathogenic virus infections from wild rodents].

    PubMed

    Nowotny, N

    1996-05-01

    For several viral infections a reservoir in wild rodents has been demonstrated. Some of the agents are known or suspected to be pathogenic for humans. Because improvements in hygiene have reduced direct human contact with rodents, domestic cats could be acting as active transmitters of these viruses from rodents to man. We selected 4 such pathogens--ortho- and parapox-, hanta- and encephalomyocarditis viruses--which, in different ways, may lead to serious human illness: Ortho- and parapoxvirus infections may cause localized pox lesions following direct skin contact. In general, the lesions heal without complications; in immunosuppressed or -deficient individuals, however, infection may generalize and take a dramatic course. Hantaviruses exist in various serotypes with different pathogenicity for human beings, varying from asymptomatic infection to highly fatal disease. In central and northern Europe the Puumala serotype is predominant causing influenza-like symptoms and renal dysfunction. Human infections arise from inhalation of aerosolized excreta of persistently infected rodents. Infections of man associated with encephalomyocarditis virus were demonstrated sporadically in cases of encephalitis and meningitis. In the present study, we investigated in 200 feline serum samples the prevalence of antibodies to ortho- and parapox-, hanta- and encephalomyocarditis virus. All serum samples were from cats that had been allowed to roam outside and to hunt. They were submitted from all parts of Austria for routine diagnosis in 1993. Four per cent of cats showed antibodies to orthopoxviruses with haemagglutination inhibition (HI) titres of 16-512; because of extensive cross-reactivity, positive samples reacted with all investigated orthopoxviruses (a feline orthopoxvirus recently isolated in Vienna, the reference strain of cowpox virus, Brighton, and vaccinia virus, strain IHD), only varying in titre. The specificity of the results was confirmed by virus neutralisation (VN

  4. Antimicrobial and antibiofilm potential of biosurfactants isolated from lactobacilli against multi-drug-resistant pathogens

    PubMed Central

    2014-01-01

    Background Biosurfactants (BS) are amphiphilic compounds produced by microbes, either on the cell surface or secreted extracellularly. BS exhibit strong antimicrobial and anti-adhesive properties, making them good candidates for applications used to combat infections. In this study, our goal was to assess the in vitro antimicrobial, anti-adhesive and anti-biofilm abilities of BS produced by Lactobacillus jensenii and Lactobacillus rhamnosus against clinical Multidrug Resistant (MDR) strains of Acinetobacter baumannii, Escherichia coli, and Staphylococcus aureus (MRSA). Cell-bound BS from both L. jensenii and L. rhamnosus were extracted and isolated. The surface activities of crude BS samples were evaluated using an oil spreading assay. The antimicrobial, anti-adhesive and anti-biofilm activities of both BS against the above mentioned MDR pathogens were determined. Results Surface activities for both BS ranged from 6.25 to 25 mg/ml with clear zones observed between 7 and 11 cm. BS of both L. jensenii and L. rhamnosus showed antimicrobial activities against A. baumannii, E. coli and S. aureus at 25-50 mg/ml. Anti-adhesive and anti-biofilm activities were also observed for the aforementioned pathogens between 25 and 50 mg/ml. Finally, analysis by electron microscope indicated that the BS caused membrane damage for A. baumannii and pronounced cell wall damage in S. aureus. Conclusion Our results indicate that BS isolated from two Lactobacilli strains has antibacterial properties against MDR strains of A. baumannii, E. coli and MRSA. Both BS also displayed anti-adhesive and anti-biofilm abilities against A. baumannii, E. coli and S. aureus. Together, these capabilities may open up possibilities for BS as an alternative therapeutic approach for the prevention and/or treatment of hospital-acquired infections. PMID:25124936

  5. Comparative genomics of multiple strains of Pseudomonas cannabina pv. alisalensis, a potential model pathogen of both Monocots and Dicots

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Comparative genomics of closely related pathogens that differ in host range can provide insights into mechanisms of host-pathogen interactions and host adaptation. Sequencing multiple strains of the same pathogen further reveals information concerning pathogen diversity and the molecular basis of vi...

  6. Annual variations and effects of temperature on Legionella spp. and other potential opportunistic pathogens in a bathroom.

    PubMed

    Lu, Jingrang; Buse, Helen; Struewing, Ian; Zhao, Amy; Lytle, Darren; Ashbolt, Nicholas

    2017-01-01

    Opportunistic pathogens (OPs) in drinking water, like Legionella spp., mycobacteria, Pseudomonas aeruginosa, and free-living amobae (FLA) are a risk to human health, due to their post-treatment growth in water systems. To assess and manage these risks, it is necessary to understand their variations and environmental conditions for the water routinely used. We sampled premise tap (N cold = 26, N hot = 26) and shower (N shower = 26) waters in a bathroom and compared water temperatures to levels of OPs via qPCR and identified Legionella spp. by 16S ribosomal RNA (rRNA) gene sequencing. The overall occurrence and cell equivalent quantities (CE L(-1)) of Mycobacterium spp. were highest (100 %, 1.4 × 10(5)), followed by Vermamoeba vermiformis (91 %, 493), Legionella spp. (59 %, 146), P. aeruginosa (14 %, 10), and Acanthamoeba spp. (5 %, 6). There were significant variations of OP's occurrence and quantities, and water temperatures were associated with their variations, especially for Mycobacterium spp., Legionella spp., and V. vermiformis. The peaks observed for Legionella, mainly consisted of Legionella pneumophila sg1 or Legionella anisa, occurred in the temperature ranged from 19 to 49 °C, while Mycobacterium spp. and V. vermiformis not only co-occurred with Legionella spp. but also trended to increase with increasing temperatures. There were higher densities of Mycobacterium in first than second draw water samples, indicating their release from faucet/showerhead biofilm. Legionella spp. were mostly at detectable levels and mainly consisted of L. pneumophila, L. anisa, Legionella donaldsonii, Legionella tunisiensis, and an unknown drinking water isolate based on sequence analysis. Results from this study suggested potential health risks caused by opportunistic pathogens when exposed to warm shower water with low chlorine residue and the use of Mycobacterium spp. as an indicator of premise pipe biofilm and the control management of those potential

  7. Lactobacillus crispatus L1: high cell density cultivation and exopolysaccharide structure characterization to highlight potentially beneficial effects against vaginal pathogens

    PubMed Central

    2014-01-01

    Background Vaginal lactic acid bacteria defend the host against pathogens through a combination of competitive exclusion, competition for nutrients, production of antimicrobial substances and through the activation of the immune system. A new human isolate named Lactobacillus crispatus L1 was characterized in this work, and a preliminary evaluation of its probiotic potential is described together with a process to obtain a high productivity of viable biomass. Results In a simulated digestion process 1.8⋅1010 cells∙ml−1 survived the gastric environment with 80% viability, without being affected by small intestine juices. Experiments on six different C sources were performed to analyze growth and organic acids production and, glucose, provided the best performances. A microfiltration strategy was exploited to improve the cellular yield in 2 L-fermentation processes, reaching 27 g · l−1 of dry biomass. Moreover, L. crispatus L1 demonstrated a greater stability to high concentrations of lactic acid, compared to other lactobacilli. The specific L. crispatus L1 exopolysaccharide was purified from the fermentation broth and characterized by NMR showing structural features and similarity to exopolysaccharides produced by pathogenic strains. Live L. crispatus L1 cells strongly reduced adhesion of a yeast pathogenic strain, Candida albicans in particular, in adherence assays. Interestingly a higher expression of the human defensin HBD-2 was also observed in vaginal cells treated with the purified exopolysaccharide, indicating a possible correlation with C. albicans growth inhibition. Conclusions The paper describes the evaluation of L. crispatus L1 as potential vaginal probiotic and the fermentation processes to obtain high concentrations of viable cells. PMID:24884965

  8. Opportunistic invasive fungal pathogen Macrophomina phaseolina prognosis from immunocompromised humans to potential mitogenic RBL with an exceptional and novel antitumor and cytotoxic effect.

    PubMed

    Arora, P; Dilbaghi, N; Chaudhury, A

    2012-02-01

    With the ever-increasing risk for fungal infections, one can no longer ignore fungi. It is imperative that clinical manifestations "presume fungus" with their epidemiologic and pathogenic features when evaluating a potentially infected patient. In the high-risk patient groups, fungi with intrinsic resistance to antifungal agents already exist, with a tendency to emerge as opportunistic pathogens. One of the smart pathogens is Macrophomina phaseolina, with the potential to disarm plant, animal, and human immunity. The response prophylaxis may vary from antifungal therapy and surgical measures to biochemical (Rhizoctonia bataticola lectin [RBL] with antitumor and cytotoxic nature) and gene therapeutics.

  9. The ethics of biosafety considerations in gain-of-function research resulting in the creation of potential pandemic pathogens.

    PubMed

    Evans, Nicholas Greig; Lipsitch, Marc; Levinson, Meira

    2015-11-01

    This paper proposes an ethical framework for evaluating biosafety risks of gain-of-function (GOF) experiments that create novel strains of influenza expected to be virulent and transmissible in humans, so-called potential pandemic pathogens (PPPs). Such research raises ethical concerns because of the risk that accidental release from a laboratory could lead to extensive or even global spread of a virulent pathogen. Biomedical research ethics has focused largely on human subjects research, while biosafety concerns about accidental infections, seen largely as a problem of occupational health, have been ignored. GOF/PPP research is an example of a small but important class of research where biosafety risks threaten public health, well beyond the small number of persons conducting the research.We argue that bioethical principles that ordinarily apply only to human subjects research should also apply to research that threatens public health, even if, as in GOF/PPP studies, the research involves no human subjects. Specifically we highlight the Nuremberg Code's requirements of 'fruitful results for the good of society, unprocurable by other methods', and proportionality of risk and humanitarian benefit, as broad ethical principles that recur in later documents on research ethics and should also apply to certain types of research not involving human subjects. We address several potential objections to this view, and conclude with recommendations for bringing these ethical considerations into policy development.

  10. The Ethics of Biosafety Considerations in Gain-of-Function Research Resulting in the Creation of Potential Pandemic Pathogens

    PubMed Central

    Lipsitch, Marc; Levinson, Meira

    2015-01-01

    This paper proposes an ethical framework for evaluating biosafety risks of gain-of-function (GOF) experiments that create novel strains of influenza expected to be virulent and transmissible in humans, so-called potential pandemic pathogens (PPP). Such research raises ethical concerns because of the risk that accidental release from a laboratory could lead to extensive or even global spread of a virulent pathogen. Biomedical research ethics has focused largely on human subjects research, while biosafety concerns about accidental infections, seen largely as a problem of occupational health, have been ignored. GOF/PPP research is an example of a small but important class of research where biosafety risks threaten public health, well beyond the small number of persons conducting the research. We argue that bioethical principles that ordinarily apply only to human subjects research should also apply to research that threatens public health, even if, as in GOF/PPP studies, the research involves no human subjects. Specifically we highlight the Nuremberg Code’s requirements of “fruitful results for the good of society, unprocurable by other methods,” and proportionality of risk and humanitarian benefit, as broad ethical principles that recur in later documents on research ethics and should also apply to certain types of research not involving human subjects. We address several potential objections to this view, and conclude with recommendations for bringing these ethical considerations into policy development. PMID:26320212

  11. POTENTIALLY PATHOGENIC FREE-LIVING AMOEBAE IN SOME FLOOD-AFFECTED AREAS DURING 2011 CHIANG MAI FLOOD

    PubMed Central

    Wannasan, Anchalee; Uparanukraw, Pichart; Songsangchun, Apichart; Morakote, Nimit

    2013-01-01

    SUMMARY The survey was carried out to investigate the presence of potentially pathogenic free-living amoebae (FLA) during flood in Chiang Mai, Thailand in 2011. From different crisis flood areas, seven water samples were collected and tested for the presence of amoebae using culture and molecular methods. By monoxenic culture, FLA were detected from all samples at 37 °C incubation. The FLA growing at 37 °C were morphologically identified as Acanthamoeba spp., Naegleria spp. and some unidentified amoebae. Only three samples (42.8%), defined as thermotolerant FLA, continued to grow at 42 °C. By molecular methods, two non-thermotolerant FlA were shown to have 99% identity to Acanthamoeba sp. and 98% identity to Hartmannella vermiformis while the two thermotolerant FLA were identified as Echinamoeba exundans (100% identity) and Hartmannella sp. (99% identity). This first report of the occurrence of FLA in water during the flood disaster will provide information to the public to be aware of potentially pathogenic FLA. PMID:24213194

  12. The adaptive potential of a plant pathogenic fungus, Rhizoctonia solani AG-3, under heat and fungicide stress.

    PubMed

    Willi, Yvonne; Frank, Aline; Heinzelmann, Renate; Kälin, Andrea; Spalinger, Lena; Ceresini, Paulo C

    2011-07-01

    The ability to improve fitness via adaptive evolution may be affected by environmental change. We tested this hypothesis in an in vitro experiment with the plant pathogen Rhizoctonia solani Anastomosis Group 3 (AG-3), assessing genetic and environmental variances under two temperatures (optimal and higher than optimal) and three fungicide concentrations (no fungicide, low and high concentration of a copper-based fungicide). We measured the mean daily growth rate, the coefficient of variation for genotypic (I (G)) and environmental variance (I (E)) in growth, and broad-sense heritability in growth. Both higher temperature and increased fungicide concentration caused a decline in growth, confirming their potential as stressors for the pathogen. All types of standardized variances in growth-I (G), phenotypic variance, and I (E) as a trend-increased with elevated stress. However, heritability was not significantly higher under enhanced stress because the increase in I (G) was counterbalanced by somewhat increased I (E). The results illustrate that predictions for adaptation under environmental stress may depend on the type of short-term evolvability measure. Because mycelial growth is linked to fitness, I (G) reflects short-term evolvability better than heritability, and it indicates that the evolutionary potential of R. solani is positively affected by stress.

  13. Potentially pathogenic free-living amoebae in some flood-affected areas during 2011 Chiang Mai flood.

    PubMed

    Wannasan, Anchalee; Uparanukraw, Pichart; Songsangchun, Apichart; Morakote, Nimit

    2013-01-01

    The survey was carried out to investigate the presence of potentially pathogenic free-living amoebae (FLA) during flood in Chiang Mai, Thailand in 2011. From different crisis flood areas, seven water samples were collected and tested for the presence of amoebae using culture and molecular methods. By monoxenic culture, FLA were detected from all samples at 37 °C incubation. The FLA growing at 37 °C were morphologically identified as Acanthamoeba spp., Naegleria spp. and some unidentified amoebae. Only three samples (42.8%), defined as thermotolerant FLA, continued to grow at 42 °C. By molecular methods, two non-thermotolerant FlA were shown to have 99% identity to Acanthamoeba sp. and 98% identity to Hartmannella vermiformis while the two thermotolerant FLA were identified as Echinamoeba exundans (100% identity) and Hartmannella sp. (99% identity). This first report of the occurrence of FLA in water during the flood disaster will provide information to the public to be aware of potentially pathogenic FLA.

  14. Review of mobile communication devices as potential reservoirs of nosocomial pathogens.

    PubMed

    Brady, R R W; Verran, J; Damani, N N; Gibb, A P

    2009-04-01

    Innovation in mobile communication technology has provided novel approaches to the delivery of healthcare and improvements in the speed and quality of routine medical communication. Bacterial contamination of mobile communication devices (MCDs) could be an important issue affecting the implementation of effective infection control measures and might have an impact on efforts to reduce cross-contamination. This review examines recent studies reporting bacterial contamination of MCDs, most demonstrating that 9-25% of MCDs are contaminated with pathogenic bacteria. We examine previously investigated risk factors for MCD contamination in addition to work on surface decontamination of the device. Recommendations to reduce contamination risks include staff education, strict hand hygiene measures, guidelines on device cleaning and consideration of the restrictions regarding use of mobile phone technology in certain high risk areas, for example, operating theatres, intensive care units and burns units. Further work is required to evaluate the benefit of such interventions on MCD contamination and to determine whether a link exists between contamination and subsequent patient infection.

  15. Serologic survey for selected arboviruses and other potential pathogens in wildlife from Mexico.

    PubMed

    Aguirre, A A; McLean, R G; Cook, R S; Quan, T J

    1992-07-01

    During 1988 and 1989, a serologic survey of wildlife was conducted in northeastern Mexico to determine the presence, prevalence, and distribution of arboviruses and other selected disease agents. Eighty mammal specimens were tested. Antibodies to vesicular stomatitis-Indiana, Venezuelan equine encephalitis-Mena II, Rio Grande virus, and vesicular stomatitis-New Jersey were detected predominantly in small mammals. Deer and mouflon (Ovis musimon) had antibodies to bluetongue and epizootic hemorrhagic disease. Two species had serologic evidence of recent exposure to Francisella tularensis. A white-tailed deer (Odocoileus virginianus) had antibodies to Anaplasma marginale. All specimens tested for antibodies against Yersinia pestis and Brucella abortus were negative. Sera from 315 birds were tested for antibody against five equine encephalitis viruses and six avian pathogens. During 1988, antibodies to Venezuelan equine encephalitis-Mena II, Venezuelan equine encephalitis-TC83, St. Louis encephalitis, eastern equine encephalitis, and western equine encephalitis were detected in birds of several species. Antibodies to Pasteurella multocida and Newcastle disease virus were also detected. Birds from five species presented antibodies to Mycoplasma meleagridis. Specimens tested for M. gallisepticum, M. synoviae, and Chlamydia psittaci were negative. To the best of our knowledge, this survey represents the first serologic evidence of bluetongue, Cache Valley virus, epizootic hemorrhagic disease, Jamestown Canyon virus, vesicular stomatitis-Indiana, vesicular stomatitis-New Jersey, Rio Grande virus, and tularemia reported among wildlife in Mexico.

  16. Evidence for carry-over effects of predator exposure on pathogen transmission potential

    PubMed Central

    Roux, Olivier; Vantaux, Amélie; Roche, Benjamin; Yameogo, Koudraogo B.; Dabiré, Kounbobr R.; Diabaté, Abdoulaye; Simard, Frederic; Lefèvre, Thierry

    2015-01-01

    Accumulating evidence indicates that species interactions such as competition and predation can indirectly alter interactions with other community members, including parasites. For example, presence of predators can induce behavioural defences in the prey, resulting in a change in susceptibility to parasites. Such predator-induced phenotypic changes may be especially pervasive in prey with discrete larval and adult stages, for which exposure to predators during larval development can have strong carry-over effects on adult phenotypes. To the best of our knowledge, no study to date has examined possible carry-over effects of predator exposure on pathogen transmission. We addressed this question using a natural food web consisting of the human malaria parasite Plasmodium falciparum, the mosquito vector Anopheles coluzzii and a backswimmer, an aquatic predator of mosquito larvae. Although predator exposure did not significantly alter mosquito susceptibility to P. falciparum, it incurred strong fitness costs on other key mosquito life-history traits, including larval development, adult size, fecundity and longevity. Using an epidemiological model, we show that larval predator exposure should overall significantly decrease malaria transmission. These results highlight the importance of taking into account the effect of environmental stressors on disease ecology and epidemiology. PMID:26674956

  17. Evidence for carry-over effects of predator exposure on pathogen transmission potential.

    PubMed

    Roux, Olivier; Vantaux, Amélie; Roche, Benjamin; Yameogo, Koudraogo B; Dabiré, Kounbobr R; Diabaté, Abdoulaye; Simard, Frederic; Lefèvre, Thierry

    2015-12-22

    Accumulating evidence indicates that species interactions such as competition and predation can indirectly alter interactions with other community members, including parasites. For example, presence of predators can induce behavioural defences in the prey, resulting in a change in susceptibility to parasites. Such predator-induced phenotypic changes may be especially pervasive in prey with discrete larval and adult stages, for which exposure to predators during larval development can have strong carry-over effects on adult phenotypes. To the best of our knowledge, no study to date has examined possible carry-over effects of predator exposure on pathogen transmission. We addressed this question using a natural food web consisting of the human malaria parasite Plasmodium falciparum, the mosquito vector Anopheles coluzzii and a backswimmer, an aquatic predator of mosquito larvae. Although predator exposure did not significantly alter mosquito susceptibility to P. falciparum, it incurred strong fitness costs on other key mosquito life-history traits, including larval development, adult size, fecundity and longevity. Using an epidemiological model, we show that larval predator exposure should overall significantly decrease malaria transmission. These results highlight the importance of taking into account the effect of environmental stressors on disease ecology and epidemiology.

  18. Determination of the relative economic impact of different molecular-based laboratory algorithms for respiratory viral pathogen detection, including Pandemic (H1N1), using a secure web based platform

    PubMed Central

    2011-01-01

    Background During period of crisis, laboratory planners may be faced with a need to make operational and clinical decisions in the face of limited information. To avoid this dilemma, our laboratory utilizes a secure web based platform, Data Integration for Alberta Laboratories (DIAL) to make near real-time decisions. This manuscript utilizes the data collected by DIAL as well as laboratory test cost modeling to identify the relative economic impact of four proposed scenarios of testing for Pandemic H1N1 (2009) and other respiratory viral pathogens. Methods Historical data was collected from the two waves of the pandemic using DIAL. Four proposed molecular testing scenarios were generated: A) Luminex respiratory virus panel (RVP) first with/without US centers for Disease Control Influenza A Matrix gene assay (CDC-M), B) CDC-M first with/without RVP, C) RVP only, and D) CDC-M only. Relative cost estimates of different testing algorithm were generated from a review of historical costs in the lab and were based on 2009 Canadian dollars. Results Scenarios A and B had similar costs when the rate of influenza A was low (< 10%) with higher relative cost in Scenario A with increasing incidence. Scenario A provided more information about mixed respiratory virus infection as compared with Scenario B. Conclusions No one approach is applicable to all conditions. Testing costs will vary depending on the test volume, prevalence of influenza A strains, as well as other circulating viruses and a more costly algorithm involving a combination of different tests may be chosen to ensure that tests results are returned to the clinician in a quicker manner. Costing should not be the only consideration for determination of laboratory algorithms. PMID:21645365

  19. Respiratory papillomas

    PubMed Central

    Alagusundaramoorthy, Sayee Sundar; Agrawal, Abhinav

    2016-01-01

    Papillomas are known to occur in the lower respiratory tract. They are however, rare compared to their occurrence in the upper respiratory tract. These are generally exophytic tumors in the more proximal upper airways however cases with more distal location with an inverted growth pattern have also been described in the literature. These can be solitary or multiple and multifocality associated with multiple papillomas in the upper respiratory/aerodigestive tract. The four major types of respiratory papillomas are (1) Recurrent respiratory papillomas, (2) solitary squamous papillomas, (3) solitary glandular papillomas, (4) mixed papillomas. We review the incidence, etiopathology, diagnosis, and possible treatment modalities and algorithms for these respiratory papillomas. PMID:27625447

  20. The Pathogenic Potential of Proteus mirabilis Is Enhanced by Other Uropathogens during Polymicrobial Urinary Tract Infection.

    PubMed

    Armbruster, Chelsie E; Smith, Sara N; Johnson, Alexandra O; DeOrnellas, Valerie; Eaton, Kathryn A; Yep, Alejandra; Mody, Lona; Wu, Weisheng; Mobley, Harry L T

    2017-02-01

    Urinary catheter use is prevalent in health care settings, and polymicrobial colonization by urease-positive organisms, such as Proteus mirabilis and Providencia stuartii, commonly occurs with long-term catheterization. We previously demonstrated that coinfection with P. mirabilis and P. stuartii increased overall urease activity in vitro and disease severity in a model of urinary tract infection (UTI). In this study, we expanded these findings to a murine model of catheter-associated UTI (CAUTI), delineated the contribution of enhanced urease activity to coinfection pathogenesis, and screened for enhanced urease activity with other common CAUTI pathogens. In the UTI model, mice coinfected with the two species exhibited higher urine pH values, urolithiasis, bacteremia, and more pronounced tissue damage and inflammation compared to the findings for mice infected with a single species, despite having a similar bacterial burden within the urinary tract. The presence of P. stuartii, regardless of urease production by this organism, was sufficient to enhance P. mirabilis urease activity and increase disease severity, and enhanced urease activity was the predominant factor driving tissue damage and the dissemination of both organisms to the bloodstream during coinfection. These findings were largely recapitulated in the CAUTI model. Other uropathogens also enhanced P. mirabilis urease activity in vitro, including recent clinical isolates of Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae, and Pseudomonas aeruginosa We therefore conclude that the underlying mechanism of enhanced urease activity may represent a widespread target for limiting the detrimental consequences of polymicrobial catheter colonization, particularly by P. mirabilis and other urease-positive bacteria.

  1. Effectiveness of serum megakaryocyte potentiating factor in evaluating the effects of chrysotile and its heated products on respiratory organs

    SciTech Connect

    Takata, Ayako; Yamauchi, Hiroshi; Toya, Tadao; Miyamoto-Kohno, Sayako; Iwatatsu, Yuka; Teranaka, Iroha; Aminaka, Masahito; Yamashita, Kiyotsugu; Kohyama, Norihiko

    2011-04-15

    Chrysotile (CH), the most common form of asbestos, is rendered less toxic by heating it at 1000 {sup o}C and converting it to forsterite (FO-1000). However, further safety tests are needed to evaluate human health risk of these materials. It has been reported that serum concentrations of megakaryocyte potentiating factor N-ERC/mesothelin become elevated in patients with mesotheliomas caused by asbestos exposure. In this study, a single 2 mg dose of CH or FO-1000 was intratracheally administered to rats. Within 180 days after the administrations, serum N-ERC/mesothelin concentrations, levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG) in lung tissues and pathological changes in respiratory organs were determined. In the CH group, a significant increase in serum N-ERC/mesothelin concentrations was observed immediately after intratracheal administration, and the elevation lasted for 30 days. In lung tissues, positive staining for 8-OHdG in bronchioles, alveolar epithelium, inflammatory cells, and granulomas was evidence of a marked DNA oxidative damage. Furthermore, measurements of 8-OHdG in lung tissues based on the HPLC-ECD method suggested that serum N-ERC/mesothelin concentrations tended to increase when there are significant DNA damages in lung tissues. In contrast, in the FO-1000 group, a marked rise in serum N-ERC/mesothelin concentrations occurred only in the early phase (1-7 days) after intratracheal administration. Similarly, FO-1000 induced elevation of 8-OHdG in lung tissues was transient and modest compared with those of the CH-treated animals. In both the CH and FO-1000 groups, we observed significant correlations between serum N-ERC/mesothelin concentrations and lung 8-OHdG concentrations (r = 0.559, p = 0.001 for the CH group; r = 0.516, p = 0.01 for the FO-1000 group). In summary, we demonstrated the possibility of using serum N-ERC/mesothelin concentrations as a useful biomarker for early phase exposure to either CH or FO-1000.

  2. Effect of autonomic blocking agents on the respiratory-related oscillations of ventricular action potential duration in humans

    PubMed Central

    van Duijvenboden, Stefan; Hanson, Ben; Child, Nick; Orini, Michele; Rinaldi, Christopher A.; Gill, Jaswinder S.

    2015-01-01

    Ventricular action potential duration (APD) is an important component of many physiological functions including arrhythmogenesis. APD oscillations have recently been reported in humans at the respiratory frequency. This study investigates the contribution of the autonomic nervous system to these oscillations. In 10 patients undergoing treatment for supraventricular arrhythmias, activation recovery intervals (ARI; a conventional surrogate for APD) were measured from multiple left and right ventricular (RV) endocardial sites, together with femoral artery pressure. Respiration was voluntarily regulated and heart rate clamped by RV pacing. Sympathetic and parasympathetic blockade was achieved using intravenous metoprolol and atropine, respectively. Metroprolol reduced the rate of pressure development (maximal change in pressure over time): 1,271 (± 646) vs. 930 (± 433) mmHg/s; P < 0.01. Systolic blood pressure (SBP) showed a trend to decrease after metoprolol, 133 (± 21) vs. 128 (± 25) mmHg; P = 0.06, and atropine infusion, 122 (± 26) mmHg; P < 0.05. ARI and SBP exhibited significant cyclical variations (P < 0.05) with respiration in all subjects with peak-to-peak amplitudes ranging between 0.7 and 17.0 mmHg and 1 and 16 ms, respectively. Infusion of metoprolol reduced the mean peak-to-peak amplitude [ARI, 6.2 (± 1.4) vs. 4.4 (± 1.0) ms, P = 0.008; SBP, 8.4 (± 1.6) vs. 6.2 (± 2.0) mmHg, P = 0.002]. The addition of atropine had no significant effect. ARI, SBP, and respiration showed significant coupling (P < 0.05) at the breathing frequency in all subjects. Directed coherence from respiration to ARI was high and reduced after metoprolol infusion [0.70 (± 0.17) vs. 0.50 (± 0.23); P < 0.05]. These results suggest a role of respiration in modulating the electrophysiology of ventricular myocardium in humans, which is partly, but not totally, mediated by β-adrenergic mechanisms. PMID:26475587

  3. Quantitative prediction of respiratory tidal volume based on the external torso volume change: a potential volumetric surrogate

    NASA Astrophysics Data System (ADS)

    Li, Guang; Arora, Naveen C.; Xie, Huchen; Ning, Holly; Lu, Wei; Low, Daniel; Citrin, Deborah; Kaushal, Aradhana; Zach, Leor; Camphausen, Kevin; Miller, Robert W.

    2009-04-01

    An external respiratory surrogate that not only highly correlates with but also quantitatively predicts internal tidal volume should be useful in guiding four-dimensional computed tomography (4DCT), as well as 4D radiation therapy (4DRT). A volumetric surrogate should have advantages over external fiducial point(s) for monitoring respiration-induced motion of the torso, which deforms in synchronization with a patient-specific breathing pattern. This study establishes a linear relationship between the external torso volume change (TVC) and lung air volume change (AVC) by validating a proposed volume conservation hypothesis (TVC = AVC) throughout the respiratory cycle using 4DCT and spirometry. Fourteen patients' torso 4DCT images and corresponding spirometric tidal volumes were acquired to examine this hypothesis. The 4DCT images were acquired using dual surrogates in ciné mode and amplitude-based binning in 12 respiratory stages, minimizing residual motion artifacts. Torso and lung volumes were calculated using threshold-based segmentation algorithms and volume changes were calculated relative to the full-exhalation stage. The TVC and AVC, as functions of respiratory stages, were compared, showing a high correlation (r = 0.992 ± 0.005, p < 0.0001) as well as a linear relationship (slope = 1.027 ± 0.061, R2 = 0.980) without phase shift. The AVC was also compared to the spirometric tidal volumes, showing a similar linearity (slope = 1.030 ± 0.092, R2 = 0.947). In contrast, the thoracic and abdominal heights measured from 4DCT showed relatively low correlation (0.28 ± 0.44 and 0.82 ± 0.30, respectively) and location-dependent phase shifts. This novel approach establishes the foundation for developing an external volumetric respiratory surrogate.

  4. Zoonotic potential of multidrug-resistant extraintestinal pathogenic Escherichia coli obtained from healthy poultry carcasses in Salvador, Brazil.

    PubMed

    Lima-Filho, José Vitor; Martins, Liliane Vilela; Nascimento, Danielle Cristina de Oliveira; Ventura, Roberta Ferreira; Batista, Jacqueline Ellen Camelo; Silva, Ayrles Fernanda Brandão; Ralph, Maria Taciana; Vaz, Renata Valença; Rabello, Carlos Boa-Viagem; Silva, Isabella de Matos Mendes da; Evêncio-Neto, Joaquim

    2013-01-01

    The zoonotic potential to cause human and/or animal infections among multidrug-resistant extraintestinal pathogenic Escherichia coli from avian origin was investigated. Twenty-seven extraintestinal pathogenic E. coli isolates containing the increased survival gene (iss) were obtained from the livers of healthy and diseased poultry carcasses at two slaughterhouses in Salvador, northeastern Brazil. The antimicrobial resistance-susceptibility profiles were conducted with antibiotics of avian and/or human use by the standardized disc-diffusion method. Antimicrobial resistance was higher for levofloxacin (51.8%), amoxicillin/clavulanic acid (70.4%), ampicillin (81.5%), cefalotin (88.8%), tetracycline (100%) and streptomycin (100%). The minimum inhibitory concentrations above the resistance breakpoints of doxycycline, neomycin, oxytetracycline and enrofloxacin reached, respectively, 88.0%, 100%, 75% and 91.7% of the isolates. Strains with high and low antimicrobial resistance were i.p. administered to Swiss mice, and histopathological examination was carried out seven days after infection. Resistance to goat and human serum complement was also evaluated. The results show that Swiss mice challenged with strain 2B (resistant to 11 antimicrobials) provoked a severe degeneration of hepatocytes besides lymphocytic infiltration in the liver, whereas the spleen showed areas of degeneration of the white and red pulp. Conversely, the spleen and liver of mice challenged with strain 4A (resistant to two antimicrobials) were morphologically preserved. In addition, complement resistance to goat and human serum was high for strain 2B and low for strain 4A. Our data show that multidrug resistance and pathogenesis can be correlated in extraintestinal pathogenic E. coli strains obtained from apparently healthy poultry carcasses, increasing the risk for human public healthy.

  5. Potentially pathogenic Escherichia coli in healthy, pasture-raised sheep on farms and at the abattoir in Brazil.

    PubMed

    Maluta, Renato Pariz; Fairbrother, John Morris; Stella, Ariel Eurides; Rigobelo, Everlon Cid; Martinez, Roberto; de Ávila, Fernando Antonio

    2014-02-21

    Sheep harbor pathogenic Escherichia coli, which may cause severe disease in humans. In this study, the prevalence of Shiga toxin-producing E. coli (STEC) and enteropathogenic E. coli (EPEC) was examined in sheep feces and carcasses on three farms and at an abattoir in Brazil. The isolates were further characterized for the presence of markers recently associated with disease in humans, to investigate their possible origin and role as food-borne pathogens. At the abattoir, 99 carcass samples yielded two STEC and 10 EPEC isolates while 101 fecal samples yielded five EPEC and eight STEC isolates. On the other hand, on the farms, 202 samples yielded 44 STEC and eight EPEC isolates. The 77 isolates were typed by PFGE. Isolates with the same PFGE pattern and also those that were not restricted with XbaI were termed as "clones" (n=49). The isolates of any one clone mostly originated from the same sampling site. In addition, seven isolates encoded for novel Stx2 variants and five for Stx2e, the subtype related to porcine edema disease, which was for the first time isolated from sheep feces and carcasses. Also, three stx2-only isolates harbored genes of predicted Stx2 variants that were formed by A and B subunits of different types including Stx2a and Stx2d. The EPEC isolates were heterogeneous, 21 (91.3%) of them possessing efa1, ehxA, lpfAO113 or paa genes associated with diarrhea in humans. Thus, using markers recently associated with disease, we have demonstrated that E. coli similar to those pathogenic for humans are present in the sheep intestinal microflora, particularly at the abattoir, underlining the potential for food-borne transmission.

  6. Viral bacterial co-infection of the respiratory tract during early childhood.

    PubMed

    Brealey, Jaelle C; Sly, Peter D; Young, Paul R; Chappell, Keith J

    2015-05-01

    Acute respiratory infection (ARI) is an important cause of morbidity in children. Mixed aetiology is frequent, with pathogenic viruses and bacteria co-detected in respiratory secretions. However, the clinical significance of these viral/bacterial co-infections has long been a controversial topic. While severe bacterial pneumonia following influenza infection has been well described, associations are less clear among infections caused by viruses that are more common in young children, such as respiratory syncytial virus. Although assessing the overall contribution of bacteria to disease severity is complicated by the presence of many confounding factors in clinical studies, understanding the role of viral/bacterial co-infections in defining the outcome of paediatric ARI will potentially reveal novel treatment and prevention strategies, improving patient outcomes. This review summarizes current evidence for the clinical significance of respiratory viral/bacterial co-infections in young children, discusses possible mechanisms of cooperative interaction between these pathogens and highlights areas that require further investigation.

  7. Prevalence and pathogenic potential of Escherichia coli isolates from raw milk and raw milk cheese in Egypt.

    PubMed

    Ombarak, Rabee A; Hinenoya, Atsushi; Awasthi, Sharda Prasad; Iguchi, Atsushi; Shima, Ayaka; Elbagory, Abdel-Rahman M; Yamasaki, Shinji

    2016-03-16

    The objectives of this study were to investigate prevalence and pathogenic potential of Escherichia coli contaminating raw milk and its products in Egypt. Out of 187 dairy products including 72 raw milk samples, 55 Karish cheese and 60 Ras cheese, 222 E. coli isolates including 111, 89 and 22 were obtained from 55 raw milk samples (76.4%), 41 Karish cheese (74.5%), and 13 Ras cheese (21.7%), respectively. Isolated E. coli strains were examined for 24 representative virulence genes present in diarrheagenic E. coli (DEC) and extraintestinal pathogenic E. coli (ExPEC). Among DEC and ExPEC virulence factors, genes for enteropathogenic E. coli (eaeA, bfpA, EAF), enterohemorrhagic E. coli (stx1, stx2, eaeA), enterotoxigenic E. coli (elt, est), enteroinvasive E. coli (invE), enteroaggregative E. coli (Eagg, astA), diffusely adherent E. coli (daaD), ExPEC (cdt-I to cdt-V, cnf1, cnf2, hlyA) and putative adhesins (efa1, iha, ehaA, saa, and lpfAO113) were screened by colony hybridization assay. Out of 222 E. coli strains, 104 (46.8%) isolated from 69 (36.9%) samples carried one or more virulence genes. The most prevalent gene detected was lpfAO113 (40.5%), followed by ehaA (32.4%,), astA (3.15%,), iha (1.80%), hlyA (1.35%), stx1 (0.90%), stx2 (0.90%), eaeA (0.45%), cdt-III (0.45%) and cnf2 (0.45%). Two strains isolated from Karish cheese harbored 5 virulence genes (stx1, stx2, iha, ehaA, lpfAO113). Stx subtype was determined to be stx1 (not stx1c or stx1d) and stx2d. Indeed, expression of hemolysin A, CDT-III, CNF-II, Stx1 and Stx2d was confirmed by blood agar plate, cytotoxicity assay and Western blotting, respectively. Among the 222 E. coli strains, 54 (48.6%), 38 (42.6%) and 12 (54.7%) isolated from raw milk, Karish cheese and Ras cheese were potentially virulent, respectively. O-genotyping indicated that most of the potentially virulent E. coli isolates did not belong to clinically important O serogroups except O75, O91 and O166, which have been associated with human

  8. Respiratory Failure

    MedlinePlus

    Respiratory failure happens when not enough oxygen passes from your lungs into your blood. Your body's organs, ... brain, need oxygen-rich blood to work well. Respiratory failure also can happen if your lungs can' ...

  9. Respiratory system

    NASA Technical Reports Server (NTRS)

    Bartlett, R. G., Jr.

    1973-01-01

    The general anatomy and function of the human respiratory system is summarized. Breathing movements, control of breathing, lung volumes and capacities, mechanical relations, and factors relevant to respiratory support and equipment design are discussed.

  10. The human respiratory gate

    NASA Technical Reports Server (NTRS)

    Eckberg, Dwain L.

    2003-01-01

    Respiratory activity phasically alters membrane potentials of preganglionic vagal and sympathetic motoneurones and continuously modulates their responsiveness to stimulatory inputs. The most obvious manifestation of this 'respiratory gating' is respiratory sinus arrhythmia, the rhythmic fluctuations of electrocardiographic R-R intervals observed in healthy resting humans. Phasic autonomic motoneurone firing, reflecting the throughput of the system, depends importantly on the intensity of stimulatory inputs, such that when levels of stimulation are low (as with high arterial pressure and sympathetic activity, or low arterial pressure and vagal activity), respiratory fluctuations of sympathetic or vagal firing are also low. The respiratory gate has a finite capacity, and high levels of stimulation override the ability of respiration to gate autonomic responsiveness. Autonomic throughput also depends importantly on other factors, including especially, the frequency of breathing, the rate at which the gate opens and closes. Respiratory sinus arrhythmia is small at rapid, and large at slow breathing rates. The strong correlation between systolic pressure and R-R intervals at respiratory frequencies reflects the influence of respiration on these two measures, rather than arterial baroreflex physiology. A wide range of evidence suggests that respiratory activity gates the timing of autonomic motoneurone firing, but does not influence its tonic level. I propose that the most enduring significance of respiratory gating is its use as a precisely controlled experimental tool to tease out and better understand otherwise inaccessible human autonomic neurophysiological mechanisms.

  11. Potential pathogens, antimicrobial patterns and genotypic diversity of Escherichia coli isolates in constructed wetlands treating swine wastewater.

    PubMed

    Ibekwe, A M; Murinda, Shelton E; DebRoy, Chitrita; Reddy, Gudigopura B

    2016-02-01

    Escherichia coli populations originating from swine houses through constructed wetlands were analyzed for potential pathogens, antimicrobial susceptibility patterns, and genotypic diversity. Escherichia coli isolates (n = 493) were screened for the presence of the following virulence genes: stx1, stx2 and eae (Shiga toxin-producing E. coli [STEC]), heat-labile enterotoxin (LT) genes and heat stable toxin STa and STb (enterotoxigenic E. coli (ETEC), cytotoxin necrotizing factors 1 and 2 (cnf1 and cnf2 [necrotoxigenic E. coli- NTEC]), as well as O and H antigens, and the presence of the antibiotic resistance genes blaTEM, blaSHV, blaCMY-2, tet A, tet B, tet C, mph(A), aadA, StrA/B, sul1, sul2 and sul3. The commensal strains were further screened for 16 antimicrobials and characterized by BOX AIR-1 PCR for unique genotypes. The highest antibiotic resistance prevalence was for tetracycline, followed by erythromycin, ampicillin, streptomycin, sulfisoxazole and kanamycin. Our data showed that most of the isolates had high distribution of single or multidrug-resistant (MDR) genotypes. Therefore, the occurrence of MDR E. coli in the wetland is a matter of great concern due to possible transfer of resistance genes from nonpathogenic to pathogenic strains or vice versa in the environment.

  12. Synthesis, characterization and amoebicidal potential of locally synthesized TiO2 nanoparticles against pathogenic Acanthamoeba trophozoites in vitro.

    PubMed

    Imran, Muhammad; Muazzam, Ambreen Gul; Habib, Amir; Matin, Abdul

    2016-06-01

    Acanthamoeba is an opportunistic protozoan pathogen that plays a pivotal role in the ecosystem. It may cause blinding keratitis and fatal encephalitis involving the central nervous system. Here we synthesized pure and Zn doped TiO2 nanoparticles (~10-30nm) via sol-gel and sol-hydrothermal methods and demonstrated its impact on the biological characteristics of pathogenic Acanthamoeba castellanii. Our results revealed that pure and Zn doped TiO2 nanoparticles synthesized by sol-hydrothermal methods (ranging 5, 10, 25 and 50μg/ml) exhibited amoebicidal effects i.e., >60% of trophozoites executed under normal light at maximum dose (50μg/ml) within 1h incubation. In contrast pure/doped TiO2 obtained via sol gel method showed ~40% amoeba damage. Furthermore, amoebae growth assay demonstrated that Zn doped TiO2 also inhibited Acanthamoeba numbers up to 7days in dose dependent manner. It was interesting to note that all the tested TiO2 nanoparticles have shown maximum amoebicidal effects at pH7 which is quite relevant to amoebic growth favorable conditions. Our results confirmed that TiO2 has inhibitory effects on Acanthamoeba growth and viability. Overall, we reported the amoebicidal and amoebic growth inhibition potential of pure and Zn doped TiO2 nanoparticles against Acanthamoeba due to attached OH(-) groups, reduced size and decreased band gap of sol hydrothermally synthesized TiO2 nanoparticles.

  13. In silico serine β-lactamases analysis reveals a huge potential resistome in environmental and pathogenic species

    PubMed Central

    Brandt, Christian; Braun, Sascha D.; Stein, Claudia; Slickers, Peter; Ehricht, Ralf; Pletz, Mathias W.; Makarewicz, Oliwia

    2017-01-01

    The secretion of antimicrobial compounds is an ancient mechanism with clear survival benefits for microbes competing with other microorganisms. Consequently, mechanisms that confer resistance are also ancient and may represent an underestimated reservoir in environmental bacteria. In this context, β-lactamases (BLs) are of great interest due to their long-term presence and diversification in the hospital environment, leading to the emergence of Gram-negative pathogens that are resistant to cephalosporins (extended spectrum BLs = ESBLs) and carbapenems (carbapenemases). In the current study, protein sequence databases were used to analyze BLs, and the results revealed a substantial number of unknown and functionally uncharacterized BLs in a multitude of environmental and pathogenic species. Together, these BLs represent an uncharacterized reservoir of potentially transferable resistance genes. Considering all available data, in silico approaches appear to more adequately reflect a given resistome than analyses of limited datasets. This approach leads to a more precise definition of BL clades and conserved motifs. Moreover, it may support the prediction of new resistance determinants and improve the tailored development of robust molecular diagnostics. PMID:28233789

  14. Presence of potentially pathogenic free-living amoebae strains from well water samples in Guinea-Bissau

    PubMed Central

    Baquero, Rocío A; Reyes-Batlle, María; Nicola, Graciela G; Martín-Navarro, Carmen M; López-Arencibia, Atteneri; Guillermo Esteban, J; Valladares, Basilio; Martínez-Carretero, Enrique; Piñero, José E; Lorenzo-Morales, Jacob

    2014-01-01

    Free-living amoebae (FLA) include opportunistic pathogens such as Naegleria fowleri, Balamuthia mandrillaris, and the genera Sappinia and Acanthamoeba. In this study, a survey was conducted in order to evaluate the presence of potentially pathogenic amoebic strains in water samples collected from wells located in the western part of Guinea-Bissau. The samples were left to precipitate for 48 hours and then the sediments were seeded on non-nutrient agar plates containing Escherichia coli spread and cultures were checked daily for the presence of FLA. Identification of FLA strains was based on the morphological and polymerase chain reaction (PCR) using the 18S rDNA or 16S mitochondrial rDNA genes in the case of Naegleria and Balamuthia genera, respectively. In the case of positive samples of Acanthamoeba, strains were further classified at the genotype level by sequencing the diagnostic fragment 3 (DF3) region located in the 18S rDNA gene as previously described. Sappinia sp. was not isolated during the study and thus, no molecular analysis was performed for this genus. The obtained results revealed the presence of Acanthamoeba (genotypes T3 and T4), Naegleria fowleri, and Balamuthia mandrillaris. To the best of our knowledge, this is the first report demonstrating the presence of FLA in water bodies from Guinea-Bissau and the first report on the isolation of Balamuthia mandrillaris from environmental sources in Africa. PMID:24934796

  15. Recent Trends in Rapid Environmental Monitoring of Pathogens and Toxicants: Potential of Nanoparticle-Based Biosensor and Applications

    PubMed Central

    Koedrith, Preeyaporn; Thasiphu, Thalisa; Weon, Jong-Il; Boonprasert, Rattana; Tuitemwong, Kooranee; Tuitemwong, Pravate

    2015-01-01

    Of global concern, environmental pollution adversely affects human health and socioeconomic development. The presence of environmental contaminants, especially bacterial, viral, and parasitic pathogens and their toxins as well as chemical substances, poses serious public health concerns. Nanoparticle-based biosensors are considered as potential tools for rapid, specific, and highly sensitive detection of the analyte of interest (both biotic and abiotic contaminants). In particular, there are several limitations of conventional detection methods for water-borne pathogens due to low concentrations and interference with various enzymatic inhibitors in the environmental samples. The increase of cells to detection levels requires long incubation time. This review describes current state of biosensor nanotechnology, the advantage over conventional detection methods, and the challenges due to testing of environmental samples. The major approach is to use nanoparticles as signal reporter to increase output rather than spending time to increase cell concentrations. Trends in future development of novel detection devices and their advantages over other environmental monitoring methodologies are also discussed. PMID:25884032

  16. A molecular biological protocol to distinguish potentially human pathogenic Stenotrophomonas maltophilia from plant-associated Stenotrophomonas rhizophila.

    PubMed

    Ribbeck-Busch, Kathrin; Roder, Anja; Hasse, Dirk; de Boer, Wietse; Martínez, José Luis; Hagemann, Martin; Berg, Gabriele

    2005-11-01

    In recent years, the importance of the Gram-negative bacterium Stenotrophomonas as an opportunistic pathogen as well as in biotechnology has increased. The aim of the present study was to develop new methods for distinguishing between strains closely related to the potentially human pathogenic Stenotrophomonas maltophilia and those closely related to the plant-associated Stenotrophomonas rhizophila. To accomplish this, 58 strains were characterized by 16S rDNA sequencing and amplified ribosomal DNA restriction analysis (ARDRA), and the occurrence of specific functional genes. Based on 16S rDNA sequences, an ARDRA protocol was developed which allowed differentiation between strains of the S. maltophilia and the S. rhizophila group. As it was known that only salt-treated cells of S. rhizophila were able to synthesize the compatible solute glucosylglycerol (GG), the ggpS gene responsible for GG synthesis was used for differentiation between both species and it was confirmed that it only occurred in S. rhizophila strains. As a further genetic marker the smeD gene, which is part of the genes coding for the multidrug efflux pump SmeDEF from S. maltophilia, was used. Based on the results we propose a combination of fingerprinting techniques using the 16S rDNA and the functional genes ggpS and smeD to distinguish both Stenotrophomonas species.

  17. The Australian bush fly (Musca vetustissima) as a potential vector in the transmission of foodborne pathogens at outdoor eateries.

    PubMed

    Vriesekoop, Frank; Shaw, Rachel

    2010-03-01

    Abstract Australian outdoor activities are often accompanied by a barbeque (BBQ) with family, friends, and guests, which are often interrupted by uninvited guests in the form of the Australian bush fly, Musca vetustissima. We investigated the bacterial loading associated with the Australian bush in three different environments: on a cattle farm, in a typical urban area (shopping center car park), and at a BBQ. The highest bacterial populations per fly were found to occur in a farm environment ( approximately 9.1 x 10(4) CFU per fly), whereas the bacterial population was lowest on flies caught in an urban environment ( approximately 1.9 x 10(4) CFU per fly). The median CFU per fly caught near a BBQ was approximately 5.0 x 10(4). Escherichia coli was the most commonly isolated potential pathogen, whereas Shigella sp. was the least common bacterial isolate that was screened. All isolated foodborne pathogens or indicator bacteria were screened for antibiotic resistance against commonly prescribed antibiotics. This revealed a very high prevalence of multidrug resistance, especially among the Salmonella and Shigella isolates of 94% and 87% resistance, respectively, against amoxicillin, roxythromycin and cefaclor.

  18. Occurrence of potentially pathogenic bacteria on the hands of hospital patients before and after the introduction of patient hand disinfection.

    PubMed

    Hedin, Göran; Blomkvist, Annika; Janson, Marianne; Lindblom, Anders

    2012-10-01

    The leading cause of nosocomial infections and spread of multiresistant bacteria is considered to be the failure of healthcare workers to perform appropriate hand hygiene. The role of the hands of hospital patients in the spread of infection has received little attention. The aim of the present study was to investigate the occurrence of potentially pathogenic bacteria on the patients' hands. Quantitative cultures were repeatedly taken from the fingertips of patients at a rehabilitation clinic before and after an intervention in which patient hand disinfection was introduced and promoted. Before the intervention, the occurrence on the hands of Escherichia coli, Klebsiella spp., enterococci, Staphylococcus aureus and yeast was a common finding. The colony counts of S. aureus were often higher than the counts of other organisms. After the intervention, the level of hand contamination was lower. The difference was statistically significant (p < 0.05) concerning Enterobacteriaceae, both when the patients were resting and at lunch time, for enterococci and total bacterial counts at lunch time, and for yeast when they were resting. Concerning S. aureus, the difference was not statistically significant, neither while resting nor at lunch time. The role of the patients in the spread of pathogenic bacteria merits more discussion.

  19. Potential Use of Native and Naturalized Insect Herbivores and Fungal Pathogens of Aquatic and Wetland Plants

    DTIC Science & Technology

    2007-08-01

    reproduction (Berg 1949, Wiggins 1977, Carpenter and Lodge 1986, New- man 1991, Cronin et al. 1998). Recent studies have shown that hydrilla in...might rival melaleuca’s ability to invade the Everglades. The high reproductive potential of catclaw mimosa and the persistence of its seeds in the...exhibited inconsistent results. Biology Mt is a dematiaceous fungus that reproduces asexually by hyaline two- celled spores (Figure 16) or by

  20. In vitro study of the post-antibiotic effect and the bactericidal activity of Cefditoren and ten other oral antimicrobial agents against upper and lower respiratory tract pathogens.

    PubMed

    Dubois, J; St-Pierre, C

    2000-07-01

    The in vitro post-antibiotic effect (PAE) and batericidal activity of cefditoren was compared to that of cefixime, cefuroxime, loracarbef, cefaclor, amoxicillin, amoxicillin/clavulanate, clarithromycin, azithromycin, erythromycin, and ciprofloxacin against ATCC culture strains and clinical respiratory isolates. A PAE > 1 h was observed for cefditoren and generally for the macrolides against Streptococcus pneumoniae, beta-lactamase-negative Moraxella catarrhalis, and Streptococcus pyogenes, whereas the other beta-lactams showed mixed results. Cefditoren was the only beta-lactam showing significant bactericidal activity (>3 log reduction of viable cells) within 4 h against penicillin-resistant S. pneumoniae. Only cefditoren and ciprofloxacin showed significant bactericidal activity against beta-lactamase-negative (after 24 h) and beta-lactamase-positive strains of H. influenzae (after 12 h). Against beta-lactamase-positive strains of M. catarrhalis, cefditoren was the only agent to show significant bactericidal activity at 6 h (versus cefuroxime and ciprofloxacin at 12 h).

  1. Respiratory alkalosis

    MedlinePlus

    ... shortness of breath. Alternative Names Alkalosis - respiratory Images Respiratory system References Effros RM, Swenson ER. Acid-base balance. In: Broaddus VC, Mason RJ, Ernst JD, et al, eds. Murray and Nadel's Textbook of Respiratory Medicine . 6th ed. Philadelphia, PA: Elsevier Saunders; 2016: ...

  2. Carriage of Streptococcus pneumoniae and Other Respiratory Bacterial Pathogens in Low and Lower-Middle Income Countries: A Systematic Review and Meta-Analysis

    PubMed Central

    Adegbola, Richard A.; DeAntonio, Rodrigo; Hill, Philip C.; Roca, Anna; Usuf, Effua; Hoet, Bernard; Greenwood, Brian M.

    2014-01-01

    Background Infection with Streptococcus pneumoniae is a major cause of childhood morbidity and mortality worldwide, especially in low income countries where pneumococcal conjugate vaccines (PCVs) are still underused. In countries where PCVs have been introduced, much of their efficacy has resulted from their impact on nasopharyngeal carriage in vaccinated children. Understanding the epidemiology of carriage for S. pneumoniae and other common respiratory bacteria in developing countries is crucial for implementing appropriate vaccination strategies and evaluating their impact. Methods and Findings We have systematically reviewed published studies reporting nasopharyngeal or oropharyngeal carriage of S. pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus, and Neisseria meningitidis in children and adults in low and lower-middle income countries. Studies reporting pneumococcal carriage for healthy children <5 years of age were selected for a meta-analysis. The prevalences of carriage for S. pneumoniae, H. influenzae, and M. catarrhalis were generally higher in low income than in lower-middle income countries and were higher in young children than in adults. The prevalence of S. aureus was high in neonates. Meta-analysis of data from young children before the introduction of PCVs showed a pooled prevalence estimate of 64.8% (95% confidence interval, 49.8%–76.1%) in low income countries and 47.8% (95% confidence interval, 44.7%–50.8%) in lower-middle income countries. The most frequent serotypes were 6A, 6B, 19A, 19F, and 23F. Conclusions In low and lower-middle income countries, pneumococcal carriage is frequent, especially in children, and the spectrum of serotypes is wide. However, because data are limited, additional studies are needed to adequately assess the impact of PCV introduction on carriage of respiratory bacteria in these countries. PMID:25084351

  3. Identification of pathogenic factors potentially involved in Staphylococcus aureus keratitis using proteomics.

    PubMed

    Khan, Shamila; Cole, Nerida; Hume, Emma B H; Garthwaite, Linda L; Nguyen-Khuong, Terry; Walsh, Bradley J; Willcox, Mark D P

    2016-10-01

    Staphylococcus is a leading cause of microbial keratitis, characterized by destruction of the cornea by bacterial exoproteins and host-associated factors. The aim of this study was to compare extracellular and cell-associated proteins produced by two different isolates of S. aureus, a virulent clinical isolate (Staph 38) and a laboratory strain (Staphylococcus aureus 8325-4) of weaker virulence in the mouse keratitis model. Proteins were analyzed using 2D polyacrylamide gel electrophoresis and identified by subsequent mass spectrometry. Activity of staphylococcal adhesins was assessed by allowing strains to bind to various proteins adsorbed onto polymethylmethacrylate squares. Thirteen proteins in the extracellular fraction and eight proteins in the cell-associated fractions after bacterial growth were produced in increased amounts in the clinical isolate Staph 38. Four of these proteins were S. aureus virulence factor adhesins, fibronectin binding protein A, staphopain, glyceraldehyde-3-phosphate dehydrogenase 2 and extracellular adherence protein. The clinical isolate Staph 38 adhered to a greater extent to all mammalian proteins tested, indicating the potential of the adhesins to be active on its surface. Other proteins with increased expression in Staph 38 included potential moonlighting proteins and proteins involved in transcription or translation. This is the first demonstration of the proteome of S. aureus isolates from keratitis. These results indicate that the virulent clinical isolate produces more potentially important virulence factors compared to the less virulent laboratory strain and these may be associated with the ability of a S. aureus strain to cause more severe keratitis.

  4. Molecular methods for pathogen and microbial community detection and characterization: current and potenti