Note: This page contains sample records for the topic potential respiratory pathogens from Science.gov.
While these samples are representative of the content of Science.gov,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of Science.gov
to obtain the most current and comprehensive results.
Last update: November 12, 2013.
1

Reduction of potential respiratory pathogens by oral hygienic treatment in patients undergoing endotracheal anesthesia  

Microsoft Academic Search

Purpose.?This study was conducted to evaluate the usefulness of mechanical and chemical prophylactic oral cleansing treatments for\\u000a reducing potential respiratory pathogens existing in the oral cavity.\\u000a \\u000a \\u000a \\u000a \\u000a Methods.?Thirty-two patients scheduled to undergo oral and maxillofacial surgery that required endotracheal anesthesia were randomly\\u000a allocated to one of the two groups, the oral cleansing group (n = 16) or the noncleansing group (n

Minori Okuda; Yuzuru Kaneko; Tatsuya Ichinohe; Kazuyuki Ishihara; Katsuji Okuda

2003-01-01

2

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

Microsoft Academic Search

Background  Nasopharyngeal carriage of potential pathogens is important as it is both the major source of transmission and the prerequisite\\u000a of invasive disease. New methods for detecting carriage could improve comfort, accuracy and laboratory utility. The aims of\\u000a this study were to compare the sensitivities of a nasopharyngeal swab (NPS) and a nasal wash (NW) in detecting potential respiratory\\u000a pathogens in

Jenna F Gritzfeld; Paul Roberts; Lorna Roche; Sherouk El Batrawy; Stephen B Gordon

2011-01-01

3

Prevalence of potential respiratory pathogens in the mouths of elderly patients and effects of professional oral care  

Microsoft Academic Search

To evaluate the effectiveness of professional oral health care in reducing the risk of aspiration pneumonia, we examined the prevalence of potential respiratory pathogens in gargled samples from elderly persons. Samples were obtained from 54 elderly subjects over 65 years of age who required daily nursing care, from 21 healthy elderly subjects over 65 years old, and from 22 healthy

Shu Abe; Kazuyuki Ishihara; Katsuji Okuda

2001-01-01

4

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

PubMed Central

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.

2011-01-01

5

Genomic Sequencing Reveals Mutations Potentially Related to the Overattenuation of a Highly Pathogenic Porcine Reproductive and Respiratory Syndrome Virus  

PubMed Central

Highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) continues to evolve when serially passaged in Marc-145 cells. In this study, we analyzed the genomic and antigenic variants of HP-PRRSV strain JXA1 during in vitro passage. Protective efficacies of JXA1 from passages 100, 110, 120, 140, and 170 against the high-virulence parental virus were evaluated by inoculating pigs with each of these viruses and then challenging with JXA1 from passage 5 at 28 days postimmunization. We found that the antigenicities of JXA1 from passages after 110 were significantly reduced. Inoculation with JXA1 from passages after 110 provided only insufficient protection against the parental strain challenge, indicating that the immunogenicity of JXA1 is significantly decreased when it is in vitro passaged for 110 times and more. To identify the genomic variants that emerged during the overattenuation, eight complete genomes of highly passaged JXA1 were sequenced. One guanine deletion in the 5? untranslated region (UTR), two nucleotide substitutions in the 3? UTR, and 65 amino acid mutations in nonstructural and structural proteins that accompanied with the attenuation and overattenuation were determined. Genomic sequencing of in vitro serially passaged HP-PRRSV first identified the mutations potentially correlated with the overattenuation of a HP-PRRSV strain. These results facilitate the research aimed at elucidating the mechanisms for PRRSV genomic and antigenic changes and may also contribute to developing a safe and effective PRRSV vaccine.

Yu, Xiuling; Chen, Nanhua; Deng, Xiaoyu; Cao, Zhen; Han, Wei; Hu, Dongmei; Wu, Jiajun; Zhang, Shuo; Wang, Baoyue; Gu, Xiaoxue

2013-01-01

6

Pathogen Chip for Respiratory Tract Infections  

PubMed Central

Determining the viral etiology of respiratory tract infections (RTI) has been limited for the most part to specific primer PCR-based methods due to their increased sensitivity and specificity compared to other methods, such as tissue culture. However, specific primer approaches have limited the ability to fully understand the diversity of infecting pathogens. A pathogen chip system (PathChip), developed at the Genome Institute of Singapore (GIS), using a random-tagged PCR coupled to a chip with over 170,000 probes, has the potential to recognize all known human viral pathogens. We tested 290 nasal wash specimens from Filipino children <2 years of age with respiratory tract infections using culture and 3 PCR methods—EraGen, Luminex, and the GIS PathChip. The PathChip had good diagnostic accuracy, ranging from 85.9% (95% confidence interval [CI], 81.3 to 89.7%) for rhinovirus/enteroviruses to 98.6% (95% CI, 96.5 to 99.6%) for PIV 2, compared to the other methods and additionally identified a number of viruses not detected by these methods.

Patel, Champa; Sung, Wing-Kin; Lee, Charlie W. H.; Loh, Kuan Hon; Lucero, Marilla; Nohynek, Hanna; Nai, Geraldine; Thien, Pei Ling; Koh, Chee Wee; Chan, Yang Sun; Ma, Jianmin; Maurer-Stroh, Sebastian; Carosone-Link, Phyllis; Hibberd, Martin L.; Wong, Christopher W.

2013-01-01

7

Atypical pathogens and respiratory tract infections  

Microsoft Academic Search

ABSTRACT: The atypical respiratory pathogens Chlamydia pneumoniae, Myco- plasma,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.

F. Blasi

2004-01-01

8

Human metapneumovirus: a new respiratory pathogen  

Microsoft Academic Search

Human metapneumovirus is a recently recognized pathogen of acute respiratory tract infection (ARI) in children as well as\\u000a elderly and immunocompromised adults. The virus belongs to the family Paramyxoviridae, sub family Pneumovirinae and genus Metapneumovirus. Through genetic analysis it has been characterized into two groups A and B which are further divided into four sub-lineages.\\u000a The virus is difficult to

S. Broor; P. Bharaj; H. S. Chahar

2008-01-01

9

Moraxella catarrhalis, a human respiratory tract pathogen.  

PubMed

Moraxella catarrhalis is an exclusively human pathogen and is a common cause of otitis media in infants and children, causing 15%-20% of acute otitis media episodes. M. catarrhalis causes an estimated 2-4 million exacerbations of chronic obstructive pulmonary disease in adults annually in the United States. M. catarrhalis resembles commensal Neisseria species in culture and, thus, may be overlooked in samples from the human respiratory tract. The prevalence of colonization of the upper respiratory tract is high in infants and children but decreases substantially in adulthood. Most strains produce beta-lactamase and are thus resistant to ampicillin but susceptible to several classes of oral antimicrobial agents. Recent work has elucidated mechanisms of pathogenesis and focused on vaccine development to prevent otitis media in children and respiratory tract infections caused by M. catarrhalis in adults with chronic obstructive pulmonary disease. PMID:19480579

Murphy, Timothy F; Parameswaran, G Iyer

2009-07-01

10

Pathogenic potential of lactobacilli.  

PubMed

Lactobacilli are often considered to be commensal or beneficial participants in human microbial ecology and considerable research is being carried out into the effects of the use of lactobacilli as additives in both human and animal diets. However, lactobacilli also cause some human diseases (e.g. dental caries, rheumatic vascular disease, septicaemia and infective endocarditis (IE)), and have recently been identified as potential emerging pathogens in elderly and immunocompromised patients, particularly those receiving broad spectrum antibiotic therapy. The identification of potential pathogenic traits amongst lactobacilli will therefore facilitate the use of the organisms for probiotic purposes. The ability to aggregate human platelets is considered to be a possible pathogenic trait in the progression of IE. A comparison of bacterial cell surface properties amongst L. rhamnosus strains showed that platelets were aggregated by 5/5 IE strains and 8/16 laboratory strains. For the L. paracasei subsp. paracasei strains the respective numbers were 2/5 and 2/9. However two strains, morphological mutants of a non-aggregating strain, which had been re-isolated after passaging through rats were found to aggregate platelets. No loss of aggregating function occurred on extensive subculturing of IE strains. Aggregation also occurred with 11/14 strains for five other species, namely, Lactobacillus acidophilus, Lactobacillus fermentum, Lactobacillus oris, Lactobacillus plantarum and Lactobacillus salvivarius, with each species being represented indicating that the property is not uncommon in the genus. A comparison of IE and oral isolates of L. rhamnosus and L. paracasei subsp. paracasei and seven other Lactobacillus species, has shown that the binding of both fibronectin and fibrinogen by lactobacilli is greatly increased, up to 50 fold, when the pH is reduced from 7.0 to 5.0. Re-exposing the lactobacilli to a neutral pH environment releases most of the bound proteins, but the amount still remaining bound to the cell is several times more than is bound at neutral pH. Lactobacilli will also bind to the proteins that make up the extracellular matrix of endothelial cells. Lactobacilli bound significantly better to collagen types I and V than to types III and IV (p < 0.01). Further, strains isolated from IE cases, particularly L. rhamnosus strains, bound significantly better to types I and V than did 'normal' strains (p < 0.02). Type V collagen has been demonstrated at the sites of endothelial damage. Thus the binding of lactobacilli, particularly L. rhamnosus to these collagen types may be of importance in the early stages of colonization of the damaged heart valve.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:7703012

Harty, D W; Oakey, H J; Patrikakis, M; Hume, E B; Knox, K W

1994-12-01

11

Immune evasion by pathogens of bovine respiratory disease complex.  

PubMed

Bovine respiratory tract disease is a multi-factorial disease complex involving several viruses and bacteria. Viruses that play prominent roles in causing the bovine respiratory disease complex include bovine herpesvirus-1, bovine respiratory syncytial virus, bovine viral diarrhea virus and parinfluenza-3 virus. Bacteria that play prominent roles in this disease complex are Mannheimia haemolytica and Mycoplasma bovis. Other bacteria that infect the bovine respiratory tract of cattle are Histophilus (Haemophilus) somni and Pasteurella multocida. Frequently, severe respiratory tract disease in cattle is associated with concurrent infections of these pathogens. Like other pathogens, the viral and bacterial pathogens of this disease complex have co-evolved with their hosts over millions of years. As much as the hosts have diversified and fine-tuned the components of their immune system, the pathogens have also evolved diverse and sophisticated strategies to evade the host immune responses. These pathogens have developed intricate mechanisms to thwart both the innate and adaptive arms of the immune responses of their hosts. This review presents an overview of the strategies by which the pathogens suppress host immune responses, as well as the strategies by which the pathogens modify themselves or their locations in the host to evade host immune responses. These immune evasion strategies likely contribute to the failure of currently-available vaccines to provide complete protection to cattle against these pathogens. PMID:18218162

Srikumaran, Subramaniam; Kelling, Clayton L; Ambagala, Aruna

2007-12-01

12

Immunity to the respiratory pathogen Bordetella pertussis.  

PubMed

Bordetella pertussis causes whooping cough, a severe respiratory tract infection in infants and children, and also infects adults. Studies in murine models have shown that innate immune mechanisms involving dendritic cells, macrophages, neutrophils, natural killer cells, and antimicrobial peptides help to control the infection, while complete bacterial clearance requires cellular immunity mediated by T-helper type 1 (Th1) and Th17 cells. Whole cell pertussis vaccines (wP) are effective, but reactogenic, and have been replaced in most developed countries by acellular pertussis vaccines (aP). However, the incidence of pertussis is still high in many vaccinated populations; this may reflect sub-optimal, waning, or escape from immunity induced by current aP. Protective immunity generated by wP appears to be mediated largely by Th1 cells, whereas less efficacious alum-adjuvanted aP induce strong antibody Th2 and Th17 responses. New generation aP that induce Th1 rather than Th2 responses are required to improve vaccine efficacy and prevent further spread of B. pertussis. PMID:22718262

Higgs, R; Higgins, S C; Ross, P J; Mills, K H G

2012-06-20

13

Molecular survey of avian respiratory pathogens in commercial broiler chicken flocks with respiratory diseases in Jordan.  

PubMed

Acute respiratory tract infections are of paramount importance in the poultry industry. Avian influenza virus (AIV), infectious bronchitis virus (IBV), Newcastle disease virus (NDV), avian pneumovirus (APV), and Mycoplasma gallisepticum (MG) have been recognized as the most important pathogens in poultry. In this study, trachea swabs from 115 commercial broiler chicken flocks that suffered from respiratory disease were tested for AIV subtype H9N2, IBV, NDV, and APV by using reverse transcription PCR and for MG by using PCR. The PCR and reverse transcription PCR results showed that 13 and 14.8% of these flocks were infected with NDV and IBV, respectively, whereas 5.2, 6.0, 9.6, 10.4, 11.3, and 15.7% of these flocks were infected with both NDV and MG; MG and APV; IBV and NDV; IBV and MG; NDV and AIV; and IBV and AIV, respectively. Furthermore, 2.6% of these flocks were infected with IBV, NDV, and APV at the same time. On the other hand, 11.3% of these flocks were negative for the above-mentioned respiratory diseases. Our data showed that the above-mentioned respiratory pathogens were the most important causes of respiratory disease in broiler chickens in Jordan. Further studies are necessary to assess circulating strains, economic losses caused by infections and coinfections of these pathogens, and the costs and benefits of countermeasures. Furthermore, farmers need to be educated about the signs and importance of these pathogens. PMID:18281569

Roussan, D A; Haddad, R; Khawaldeh, G

2008-03-01

14

Viral and Bacterial Pathogens in Bovine Respiratory Disease in Finland  

PubMed Central

Pathogens causing bovine respiratory tract disease in Finland were investigated. Eighteen cattle herds with bovine respiratory disease were included. Five diseased calves from each farm were chosen for closer examination and tracheobronchial lavage. Blood samples were taken from the calves at the time of the investigation and from 86 calves 3–4 weeks later. In addition, 6–10 blood samples from animals of different ages were collected from each herd, resulting in 169 samples. Serum samples were tested for antibodies to bovine parainfluenza virus-3 (PIV-3), bovine respiratory syncytial virus (BRSV), bovine coronavirus (BCV), bovine adenovirus-3 (BAV-3) and bovine adenovirus-7 (BAV-7). About one third of the samples were also tested for antibodies to bovine virus diarrhoea virus (BVDV) with negative results. Bacteria were cultured from lavage fluid and in vitro susceptibility to selected antimicrobials was tested. According to serological findings, PIV-3, BAV-7, BAV-3, BCV and BRSV are common pathogens in Finnish cattle with respiratory problems. A titre rise especially for BAV-7 and BAV-3, the dual growth of Mycoplasma dispar and Pasteurella multocida, were typical findings in diseased calves. Pasteurella sp. strains showed no resistance to tested antimicrobials. Mycoplasma bovis and Mannheimia haemolytica were not found.

Hartel, H; Nikunen, S; Neuvonen, E; Tanskanen, R; Kivela, S-L; Aho, P; Soveri, T; Saloniemi, H

2004-01-01

15

Frequency of pathogen occurrence and antimicrobial susceptibility among community-acquired respiratory tract infections in the respiratory surveillance program study: microbiology from the medical office practice environment  

Microsoft Academic Search

Continuing problems of antimicrobial resistance have prompted the initiation of several surveillance programs. Few, if any, of these programs focus on community-acquired respiratory tract infections seen in routine office-based practices. The Respiratory Surveillance Program (RESP; 1999–2000) in 674 community-based physician office practices in the United States determined the frequency of potential bacterial pathogens including Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella

Michael A Pfaller; Anton F Ehrhardt; Ronald N Jones

2001-01-01

16

Pathogens involved in lower respiratory tract infections in general practice.  

PubMed Central

BACKGROUND: There are few investigations into the aetiology of lower respiratory tract infections (LRTIs) in general practice. AIM: To describe the aetiology of LRTI among adult patients in general practice in The Netherlands. DESIGN OF STUDY: Prospective observational study. SETTING: General practices in the Leiden region, The Netherlands. METHOD: Adult patients with a defined LRTI were included. Standard medical history and physical examination were performed. Sputum, blood and throat swabs were collected for diagnostic tests. Aetiological diagnosis, categorised as definite or possible, was based on the results of bacterial and viral cultures, serological techniques, and on polymerase chain reaction. Proportions of pathogens causing LRTI were assessed in relation to chest X-ray findings. RESULTS: A bacterial cause was established in 43 (30%), and a viral cause in 57 (39%) of the 145 patients with a LRTI. Influenza virus A was the most frequently diagnosed microorganism, followed by Haemophilus influenzae, and Mycoplasma pneumoniae. Streptococcus pneumoniae was found in 6% of the patients. CONCLUSIONS: Pathogens were found in two-thirds of the patients. In half of these patients there was a viral cause. Influenza virus A was the most frequently found pathogen. The treatment with antibiotics of at least one-third of the patients with LRTI was superfluous. This observation should result in changes in the prescription of antibiotics in LRTI.

Graffelman, A Willy; Knuistingh Neven, Arie; le Cessie, Saskia; Kroes, Aloys C M; Springer, Machiel P; van den Broek, Peterhans J

2004-01-01

17

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

PubMed Central

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.

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

1989-01-01

18

Detection of respiratory pathogens in air samples from acutely infected pigs  

PubMed Central

Pathogens causing significant respiratory disease in growing pigs include Porcine reproductive and respiratory syndrome virus, Porcine circovirus 2, swine influenza virus, porcine respiratory coronavirus, Mycoplasma hyopneumoniae, and Bordetella bronchiseptica. The objective of this research was to characterize the respiratory excretion of these pathogens by acutely infected pigs. Pigs were inoculated under experimental conditions with 1 pathogen. Samples were collected from the upper respiratory tract and exhaled air. All pathogens were detected in swabs of the upper respiratory tract, but only M. hyopneumoniae and B. bronchiseptica were detected in expired air from individually sampled, acutely infected pigs. These findings suggest either that the acutely infected pigs did not aerosolize the viruses or that the quantity of virus excreted was below the detection threshold of current sampling or assay systems, or both, at the individual-pig level.

Hermann, Joseph R.; Brockmeier, Susan L.; Yoon, Kyoung-Jin; Zimmerman, Jeffrey J.

2008-01-01

19

Pathogenicity and distribution of highly pathogenic porcine reproductive and respiratory syndrome virus in pigs.  

PubMed

The pathogenesis of highly pathogenic porcine reproductive and respiratory syndrome virus (PRRSV) strain (HuN4) is poorly understood. Therefore, highly pathogenic PRRSV strain (HuN4) and its derivative strain (HuN4-F112) (obtained by propagation in MARC145 cells for 112 passages) were inoculated into a total of 48 PRRSV-sero-negative pigs (age: 4-5?weeks) by the intranasal route. Virological, pathological and in situ hybridization analyses were performed. The results exhibited that pigs infected with HuN4 showed a loss of appetite, decrease in body weight, raised body temperature and respiratory symptoms, along with interstitial pneumonia lesions. In the HuN4 group, multifocal interstitial pneumonia with macrophage infiltration was found in the lung. The lesions in the lymph node were characterized by collapsed follicles, depletion of germinal centres and reduction in lymphocytes. Perivascular cuffing and glial nodules were observed in the brains of some pigs. By comparison, the HuN4-F112 group had milder lesions. PRRSV was detected in macrophages, alveolar epithelial cells and vascular endothelial cells in the tonsil and lymph nodes. The PRRSV amounts in the pigs infected with HuN4 were 10(5) -10(9) ?copies/ml in the blood and 10(10) -10(11) ?copies/g in the lung tissues, whereas the virus amounts with HuN4-F112 were 10(2.15) -10(3.13) ?copies/ml in the blood and 10(3.0) -10(3.6) ?copies/g in the lung. Our results demonstrate that the PRRS HuN4 virus infects alveolar epithelial cells, macrophages and vascular endothelial cells causing diffuse alveolar damage and lymph node necrosis. Its higher pathogenicity compared with HuN4-F112 virus may be explained in part by higher replication rate in the previously mentioned organs. PMID:22762447

Hu, S P; Zhang, Z; Liu, Y G; Tian, Z J; Wu, D L; Cai, X H; He, X J

2012-07-05

20

Host response to respiratory bacterial pathogens as identified by integrated analysis of human gene expression data.  

PubMed

Respiratory bacterial pathogens are one of the leading causes of infectious death in the world and a major health concern complicated by the rise of multi-antibiotic resistant strains. Therapeutics that modulate host genes essential for pathogen infectivity could potentially avoid multi-drug resistance and provide a wider scope of treatment options. Here, we perform an integrative analysis of published human gene expression data generated under challenges from the gram-negative and Gram-positive bacteria pathogens, Pseudomonas aeruginosa and Streptococcus pneumoniae, respectively. We applied a previously described differential gene and pathway enrichment analysis pipeline to publicly available host mRNA GEO datasets resulting from exposure to bacterial infection. We found 72 canonical human pathways common between four GEO datasets, representing P. aeruginosa and S. pneumoniae. Although the majority of these pathways are known to be involved with immune response, we found several interesting new interactions such as the SUMO1 pathway that might have a role in bacterial infections. Furthermore, 36 host-bacterial pathways were also shared with our previous results for respiratory virus host gene expression. Based on our pathway analysis we propose several drug-repurposing opportunities supported by the literature. PMID:24086587

Smith, Steven B; Magid-Slav, Michal; Brown, James R

2013-09-27

21

Host Response to Respiratory Bacterial Pathogens as Identified by Integrated Analysis of Human Gene Expression Data  

PubMed Central

Respiratory bacterial pathogens are one of the leading causes of infectious death in the world and a major health concern complicated by the rise of multi-antibiotic resistant strains. Therapeutics that modulate host genes essential for pathogen infectivity could potentially avoid multi-drug resistance and provide a wider scope of treatment options. Here, we perform an integrative analysis of published human gene expression data generated under challenges from the gram-negative and Gram-positive bacteria pathogens, Pseudomonas aeruginosa and Streptococcus pneumoniae, respectively. We applied a previously described differential gene and pathway enrichment analysis pipeline to publicly available host mRNA GEO datasets resulting from exposure to bacterial infection. We found 72 canonical human pathways common between four GEO datasets, representing P. aeruginosa and S. pneumoniae. Although the majority of these pathways are known to be involved with immune response, we found several interesting new interactions such as the SUMO1 pathway that might have a role in bacterial infections. Furthermore, 36 host-bacterial pathways were also shared with our previous results for respiratory virus host gene expression. Based on our pathway analysis we propose several drug-repurposing opportunities supported by the literature.

Smith, Steven B.; Magid-Slav, Michal; Brown, James R.

2013-01-01

22

Associations between Pathogens in the Upper Respiratory Tract of Young Children: Interplay between Viruses and Bacteria  

PubMed Central

Background High rates of potentially pathogenic bacteria and respiratory viruses can be detected in the upper respiratory tract of healthy children. Investigating presence of and associations between these pathogens in healthy individuals is still a rather unexplored field of research, but may have implications for interpreting findings during disease. Methodology/Principal Findings We selected 986 nasopharyngeal samples from 433 6- to 24-month-old healthy children that had participated in a randomized controlled trial. We determined the presence of 20 common respiratory viruses using real-time PCR. Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis and Staphylococcus aureus were identified by conventional culture methods. Information on risk factors was obtained by questionnaires. We performed multivariate logistic regression analyses followed by partial correlation analysis to identify the overall pattern of associations. S. pneumoniae colonization was positively associated with the presence of H. influenzae (adjusted odds ratio 1.60, 95% confidence interval 1.18–2.16), M. catarrhalis (1.78, 1.29–2.47), human rhinoviruses (1.63, 1.19–2.22) and enteroviruses (1.97, 1.26–3.10), and negatively associated with S. aureus presence (0.59, 0.35–0.98). H. influenzae was positively associated with human rhinoviruses (1.63, 1.22–2.18) and respiratory syncytial viruses (2.78, 1.06–7.28). M. catarrhalis colonization was positively associated with coronaviruses (1.99, 1.01–3.93) and adenoviruses (3.69, 1.29–10.56), and negatively with S. aureus carriage (0.42, 0.25–0.69). We observed a strong positive association between S. aureus and influenza viruses (4.87, 1.59–14.89). In addition, human rhinoviruses and enteroviruses were positively correlated (2.40, 1.66–3.47), as were enteroviruses and human bocavirus, WU polyomavirus, parainfluenza viruses, and human parechovirus. A negative association was observed between human rhinoviruses and coronaviruses. Conclusions/Significance Our data revealed high viral and bacterial prevalence rates and distinct bacterial-bacterial, viral-bacterial and viral-viral associations in healthy children, hinting towards the complexity and potential dynamics of microbial communities in the upper respiratory tract. This warrants careful consideration when associating microbial presence with specific respiratory diseases.

van den Bergh, Menno R.; Biesbroek, Giske; Rossen, John W. A.; de Steenhuijsen Piters, Wouter A. A.; Bosch, Astrid A. T. M.; van Gils, Elske J. M.; Wang, Xinhui; Boonacker, Chantal W. B.; Veenhoven, Reinier H.; Bruin, Jacob P.

2012-01-01

23

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

PubMed

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. PMID:23322542

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

2013-01-15

24

A Risk Analysis Approach to Selecting Respiratory Protection Against Airborne Pathogens Used for Bioterrorism  

Microsoft Academic Search

The authors present a quantitative risk analysis approach to estimating infection risk due to airborne pathogens exhibiting relatively large infectious dose values. The method is applied to hypothetical scenarios involving airborne spores of Bacillus anthracis. The method combines the estimated parameters for exposure intensity, the pathogen dose-response relationship, and respirator penetration values (if respiratory protection is used). Because knowledge of

Mark Nicas; Alan Hubbard

2003-01-01

25

Incidence of bacterial respiratory pathogens and their susceptibility to common antibacterial agents.  

PubMed Central

Although most respiratory tract infections are caused by viruses, bacterial pathogens are responsible for higher morbidity and mortality. Because virtually nothing is known about the etiology of bacterial respiratory pathogens in Saudi Arabia, this study examined the incidence of these organisms in 5426 patients over a 1-year period. Of the bacterial pathogens isolated from 904 patients, the most common organism was Hemophilus influenzae (31%), followed by pneumococci (22%), Pseudomonas aeruginosa (16%), and others (31%). Because the first two organisms accounted for more than 50% of isolates, their susceptibility to commonly used antibiotics was also reviewed. The results are presented here.

Qadri, S. M.; Lee, G. C.; Ueno, Y.; Burdette, J. M.

1993-01-01

26

PATHOGEN POPULATION GENETICS, EVOLUTIONARY POTENTIAL, AND DURABLE RESISTANCE  

Microsoft Academic Search

? Abstract We hypothesize,that the evolutionary potential of a pathogen,popula- tion is reflected in its population genetic structure. Pathogen populations with a high evolutionary potential are more,likely to overcome,genetic resistance than pathogen populations,with a low,evolutionary potential. We propose,a flexible framework,to predict the evolutionary potential of pathogen,populations,based on analysis of their genetic structure. According to this framework, pathogens that pose the

Bruce A. McDonald; Celeste Linde

2002-01-01

27

Comparison of the FilmArray Respiratory Panel and Prodesse Real-Time PCR Assays for Detection of Respiratory Pathogens ? †  

PubMed Central

We compared the diagnostic performance and overall respiratory pathogen detection rate of the premarket version of the FilmArray Respiratory Panel (RP) multiplex PCR assay (Idaho Technology, Inc., Salt Lake City, UT) with those of the Food and Drug Administration (FDA)-cleared Prodesse ProFlu+, ProFAST+, ProParaflu+, Pro hMPV+, and ProAdeno+ real-time PCR assays (Gen-Probe, San Diego, CA). The assays were performed on a panel of 192 nasopharyngeal-secretion specimens collected from 81 children under 1 year of age with upper respiratory tract symptoms. To resolve discordant results and confirm pathogens detected only by the larger FilmArray panel, we performed laboratory-developed real-time PCR assays. Among viruses detectable by both commercial assays (adenovirus, human metapneumovirus, influenza A virus, influenza B virus, parainfluenza viruses 1 to 3, and respiratory syncytial virus), the FilmArray and Prodesse assays showed good overall agreement (181/192 [94.3%]; kappa = 0.87; 95% CI, 0.79 to 0.94). FilmArray RP detected more parainfluenza viruses 1 and 3 than ProParaflu+ (18 versus 13) while ProAdeno+ detected more adenoviruses (11 versus 6), but these differences were not statistically significant. Additionally, FilmArray RP detected 138 pathogens (confirmed as true positives) not included in the Prodesse assays (rhinovirus [RV]/enterovirus [EV], 118; bocavirus, 8; coronavirus, 7; parainfluenza virus 4, 4; Mycoplasma pneumoniae, 1). FilmArray RP was cleared by the FDA following the completion of this study. The FDA-cleared version includes the following targets: adenovirus, coronaviruses HKU1 and NL63, human metapneumovirus (hMPV), influenza A virus (to type level only), influenza A H1 seasonal virus, influenza A H3 seasonal virus, influenza A virus H1-2009, influenza B virus, parainfluenza viruses 1 to 4, respiratory syncytial virus (RSV), and RV/EV (no differentiation). The larger panel in the FilmArray RP assay allowed the detection of additional respiratory pathogens compared to the Prodesse assays. In this population of young children with upper respiratory tract infection, RV/EV accounted for the majority of the additional pathogens detected by FilmArray RP.

Loeffelholz, M. J.; Pong, D. L.; Pyles, R. B.; Xiong, Y.; Miller, A. L.; Bufton, K. K.; Chonmaitree, T.

2011-01-01

28

Application of TaqMan Low-Density Arrays for Simultaneous Detection of Multiple Respiratory Pathogens?  

PubMed Central

The large and growing number of viral and bacterial pathogens responsible for respiratory infections poses a challenge for laboratories seeking to provide rapid and comprehensive pathogen identification. We evaluated a novel application of the TaqMan low-density array (TLDA) cards for real-time PCR detection of 21 respiratory-pathogen targets. The performance of the TLDA was compared to that of individual real-time PCR (IRTP) assays with the same primers and probes using (i) nucleic acids extracted from the 21 pathogen strains and 66 closely related viruses and bacteria and (ii) 292 clinical respiratory specimens. With spiked samples, TLDA cards were about 10-fold less sensitive than IRTP assays. By using 292 clinical specimens to generate 2,238 paired individual assays, the TLDA card exhibited 89% sensitivity (95% confidence interval [CI], 86 to 92%; range per target, 47 to 100%) and 98% specificity (95% CI, 97 to 99%; range per target, 85 to 100%) overall compared to IRTP assays as the gold standard with a threshold cycle (CT) cutoff of 43. The TLDA card approach offers promise for rapid and simultaneous identification of multiple respiratory pathogens for outbreak investigations and disease surveillance.

Kodani, Maja; Yang, Genyan; Conklin, Laura M.; Travis, Tatiana C.; Whitney, Cynthia G.; Anderson, Larry J.; Schrag, Stephanie J.; Taylor, Thomas H.; Beall, Bernard W.; Breiman, Robert F.; Feikin, Daniel R.; Njenga, M. Kariuki; Mayer, Leonard W.; Oberste, M. Steven; Tondella, Maria Lucia C.; Winchell, Jonas M.; Lindstrom, Stephen L.; Erdman, Dean D.; Fields, Barry S.

2011-01-01

29

Antibacterial activity of RU 64004 (HMR 3004), a novel ketolide derivative active against respiratory pathogens.  

PubMed Central

The antibacterial activity of RU 64004, a new ketolide, was evaluated against more than 600 bacterial strains and was compared with those of various macrolides and pristinamycin. RU 64004 had good activity against multiresistant pneumococci, whether they were erythromycin A resistant or not, including penicillin-resistant strains. RU 64004 inhibited 90% of pneumococci resistant to erythromycin A and penicillin G at 0.6 and 0.15 microg/ml, respectively. Unlike macrolides, RU 64004 did not induce the phenotype of resistance to macrolides-lincosamides-streptogramin B. Its good antibacterial activity against multiresistant pneumococci ran in parallel with its well-balanced activity against all bacteria involved in respiratory infections (e.g., Haemophilus influenzae, Moraxella catarrhalis, Streptococcus pyogenes). In contrast to all comparators (14- and 16-membered-ring macrolides and pristinamycin), RU 64004 displayed high therapeutic activity in animals infected with all major strains, irrespective of the phenotypes of the strains. The results suggest that RU 64004 has potential for use in the treatment of infections caused by respiratory pathogens including multiresistant pneumococci.

Agouridas, C; Bonnefoy, A; Chantot, J F

1997-01-01

30

Bacterial pathogens of the bovine respiratory disease complex.  

PubMed

Pneumonia caused by the bacterial pathogens discussed in this article is the most significant cause of morbidity and mortality of the BRDC. Most of these infectious bacteria are not capable of inducing significant disease without the presence of other predisposing environmental factors, physiologic stressors, or concurrent infections. Mannheimia haemolytica is the most common and serious of these bacterial agents and is therefore also the most highly characterized. There are other important bacterial pathogens of BRD, such as Pasteurella multocida, Histophulus somni, and Mycoplasma bovis. Mixed infections with these organisms do occur. These pathogens have unique and common virulence factors but the resulting pneumonic lesions may be similar. Although the amount and quality of research associated with BRD has increased, vaccination and therapeutic practices are not fully successful. A greater understanding of the virulence mechanisms of the infecting bacteria and pathogenesis of pneumonia, as well as the characteristics of the organisms that allow tissue persistence, may lead to improved management, therapeutics, and vaccines. PMID:20619191

Griffin, Dee; Chengappa, M M; Kuszak, Jennifer; McVey, D Scott

2010-07-01

31

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

PubMed

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

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

2013-07-31

32

Mechanisms, molecular and sero-epidemiology of antimicrobial resistance in bacterial respiratory pathogens isolated from Japanese children  

Microsoft Academic Search

BACKGROUND: The clinical management of community-acquired respiratory tract infections (RTIs) is complicated by the increasing worldwide prevalence of antibacterial resistance, in particular, ?-lactam and macrolide resistance, among the most common causative bacterial pathogens. This study aimed to determine the mechanisms and molecular- and sero-epidemiology of antibacterial resistance among the key paediatric respiratory pathogens in Japan. METHODS: Isolates were collected at

Keisuke Sunakawa; David J Farrell

2007-01-01

33

Genome analysis of Moraxella catarrhalis strain RH4, a human respiratory tract pathogen  

Microsoft Academic Search

Moraxella catarrhalis is an emerging human-restricted respiratory tract pathogen that is a common cause of childhood otitis media and exacerbations of chronic obstructive pulmonary disease in adults. Here, we report the first completely assembled and annotated genome sequence of an isolate of M. catarrhalis, strain RH4, which originally was isolated from blood of an infected patient. The RH4 genome consists

S. P. W. de Vries; W. Schueler; K. Riesbeck; J. P. Hays; P. W. M. Hermans; H. J. Bootsma

2010-01-01

34

Bacterial respiratory pathogens in children with inherited immune and airway disorders: nasopharyngeal carriage and disease risk.  

PubMed

Children with primary immunodeficiencies, sickle cell disease and cystic fibrosis are at risk to develop invasive bacterial infections caused by respiratory tract pathogens, in particular Streptococcus pneumoniae, Haemophilus influenzae and Staphylococcus aureus. This review article evaluates the role of nasopharyngeal colonization by these pathogens in the high prevalence of respiratory and invasive infections in children with inherited disorders affecting the immune system or the respiratory tract. We conclude that respiratory and invasive diseases that occur in children with primary immunodeficiencies or sickle cell disease are probably a result of increased nasopharyngeal colonization rates compared with healthy children. However, when the inherited disorder is characterized by local airway abnormalities such as in cystic fibrosis, enhanced nasopharyngeal colonization does not seem to play a major role in invasive disease risk. As the evidence for the role of nasopharyngeal colonization in disease risk in these specific patient groups partly comes from experimental studies and animal models, longitudinal studies in children are needed. Detailed understanding of the effect of colonization on the development of respiratory and invasive infections in children with primary immunodeficiencies, sickle cell disease or cystic fibrosis provides a justification for the selective introduction of vaccination and prophylactic antibiotic treatment. Recommendations for the use of (preventive) therapeutic strategies in these patient groups taking into account disease-specific immunologic mechanisms underlying colonization and disease are described. PMID:23552676

Verhagen, Lilly M; Luesink, Maaike; Warris, Adilia; de Groot, Ronald; Hermans, Peter W M

2013-04-01

35

Comparative in-vitro activity of carbapenem antibiotics against respiratory pathogens isolated between 1999 and 2000  

Microsoft Academic Search

.   We investigated the antibacterial activity of 12 antibiotics, inclusive of four carbapenems, against 167 strains of respiratory\\u000a pathogens isolated between 1999 and 2000. Thirty strains of methicillin-susceptible Staphylococcus aureus (MSSA), 28 strains of methicillin-resistant S. aureus (MRSA), 11 strains of penicillin-susceptible Streptococcus pneumoniae (PSSP), 29 strains of penicillin-resistant S. pneumoniae (PRSP), 30 strains of Pseudomonas aeruginosa, 14 strains of

Akira Watanabe; Yutaka Tokue; Hiroshi Takahashi; Tohru Kikuchi; Takao Kobayashi; Kazunori Gomi; Shigeru Fujimura; Satoko Yasui; Yasuko Murayama; Toshihiro Nukiwa

2001-01-01

36

Comparative in vitro activity of carbapenem antibiotics against respiratory pathogens isolated in recent years  

Microsoft Academic Search

We investigated the antibacterial activity of 12 antibiotics, including 4 carbapenems, against 200 strains of respiratory\\u000a pathogens isolated in 1997, and compared the results with those obtained in 1993. The strains examined were 38 strains of\\u000a methicillin-susceptible Staphylococcus aureus (MSSA), 32 strains of methicillin-resistant S. aureus (MRSA), 22 strains of penicillin-susceptible Streptococcus pneumoniae (PSSP), 10 strains of penicillin-resistant S. pneumoniae

Akira Watanabe; Hiroaki Kikuchi; Tohru Kikuchi; Afzalunnesa Binte Lutfor; Yutaka Tokue; Hiroshi Takahashi; Shigeru Fujimura; Satoru Shoji; Yoshihiro Honda; Yushi Nakai; Toshihiro Nukiwa

1999-01-01

37

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

PubMed

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. PMID:2877952

Tuomanen, E

1986-12-01

38

Pathogenic bacteria related to respiratory diseases in poultry with reference to Ornithobacterium rhinotracheale isolated in India  

Microsoft Academic Search

Isolation and identification of pathogenic bacteria, with special reference to Ornithobacterium rhinotracheale associated with respiratory diseases, were performed from a total of 253 biomaterials collected from 125 layers of 35 commercially reared layer farms in Namakkal of Tamil Nadu state. In total, 27 (51.9%), 18 (34.6%), 5 (9.6%) and 2 (3.8%), isolates were identified as escherichia coli , Ornithobacterium rhinotracheale

Ramasamy Gopala; Krishna Murthy; Natarajan Dorairajan; Kulandaivelu Saravanabava

39

Emergence and pathogenicity of highly pathogenic Porcine reproductive and respiratory syndrome virus in Vientiane, Lao People's Democratic Republic.  

PubMed

Highly pathogenic porcine reproductive and respiratory syndrome (HP-PRRS) characterized by high fever, high morbidity, and high mortality in pigs of all ages emerged in China in 2006 and spread rapidly throughout Southeast Asia. In July 2010, a highly contagious swine disease with clinical signs similar to those of HP-PRRS was observed in the Lao People's Democratic Republic (Lao PDR). A field investigation covering 8 pig farms and 1 slaughterhouse in 7 different districts in the capital city of Vientiane was conducted to identify the disease. Total mortality rates ranged from 6.02% in boars to 91.28% in piglets (mean 54.15%) across the farms investigated. Emergence of the HP-PRRS virus (HP-PRRSV) in Lao PDR was confirmed using real-time reverse transcription polymerase chain reaction as well as virus isolation and identification. An animal inoculation study was performed to characterize the HP-PRRSV responsible for this outbreak. Isolate Laos 1.13 was inoculated into 70-day-old specific pathogen-free pigs to study pathogenicity. Clinical signs of high fever, rubefaction, respiratory distress, nervous symptoms, and diarrhea were observed in inoculated pigs, as well as pathological hemorrhagic lesions consolidated in the lungs. Morbidity and mortality were 100% and 60%, respectively, in inoculated pigs. HP-PRRSV was re-isolated from the inoculated pigs. Results suggested that the newly emerged HP-PRRSV was responsible for recent outbreaks of the swine disease in Lao PDR. The current report highlights the importance of continuous surveillance in neighboring countries to prevent introduction of PRRS to new regions. PMID:22379051

Ni, Jianqiang; Yang, Shibiao; Bounlom, Douangngeun; Yu, Xiuling; Zhou, Zhi; Song, Jianling; Khamphouth, Vongxay; Vatthana, Theppannga; Tian, Kegong

2012-03-01

40

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

PubMed Central

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.

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

2007-01-01

41

Targeting the mitochondrial respiratory chain of Cryptococcus through antifungal chemosensitization: a model for control of non-fermentative pathogens  

Technology Transfer Automated Retrieval System (TEKTRAN)

Enhanced control of species of Cryptococcus, non-fermentative yeast pathogens, was achieved by chemosensitization through co-application of certain compounds with a conventional antimicrobial drug. The species of Cryptococcus tested showed higher sensitivity to mitochondrial respiratory chain inhibi...

42

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

Microsoft Academic Search

As the increasing prevalence of resistant strains of respiratory bacterial pathogens has recently been reported, continuous\\u000a monitoring of the susceptibility of clinical isolates to antibacterial agents is important. We performed a surveillance study\\u000a focusing on the susceptibility of major respiratory bacterial pathogens in the northeastern region of Japan to carbapenems\\u000a and control drugs. A total of 168 bacterial strains isolated

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

2011-01-01

43

Epidemiological Investigation of Nine Respiratory Pathogens in Hospitalized Children in Germany Using Multiplex Reverse-Transcriptase Polymerase Chain Reaction  

Microsoft Academic Search

The aim of this study was to generate urgently needed data on respiratory pathogens in German children using an economical\\u000a and efficient tool. Nasopharyngeal aspirates of hospitalized children 0–16 years of age with an acute respiratory tract infection\\u000a were tested by a nine-valent multiplex reverse-transcriptase polymerase chain reaction. Of 1281 children, 449 (35%) had an\\u000a acute respiratory tract infection caused

J. A. I. Weigl; W. Puppe; B. Gröndahl; H.-J. Schmitt

2000-01-01

44

Evaluating the Growth Potential of Pathogenic Bacteria in Water ? †  

PubMed Central

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.

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

2010-01-01

45

Chinese highly pathogenic porcine reproductive and respiratory syndrome virus exhibits more extensive tissue tropism for pigs  

PubMed Central

Background The highly pathogenic porcine reproductive and respiratory syndrome virus (PRRSV) emerging in China exhibits high fatality to pigs. However, the mechanism related to the increased pathogenicity of the virus remains unclear. In the present study, the differences in tissue tropism between the highly pathogenic PRRSV strain (JXwn06) and the low pathogenic PRRSV strain (HB-1/3.9) were investigated using PRRSV-specific immunohistochemistry (IHC) staining to provide evidence for elucidating possible mechanism of the pathogenicity of Chinese highly pathogenic PRRSV. Findings IHC examination showed that PRRSV antigen in the tissues including spleen, tonsil, thymus, kidney, cerebellum, stomach, small intestine, large intestine, turbinal bone and laryngeal cartilage was positive in more pigs inoculated with JXwn06 than HB-1/3.9, and the tissues including trachea, esophagus, liver, mandibular gland and thyroid gland were positive for viral antigen in the pigs inoculated with JXwn06, but not in the pigs inoculated with HB-1/3.9. Meanwhile, we observed that epithelium in tissues including interlobular bile duct in liver, distal renal tubule of kidney, esophageal gland and tracheal gland were positive for viral antigen only in JXwn06-inoculated pigs, and epithelium of gastric mucosa and fundic gland, and intestinal gland were positive for viral antigen in both JXwn06- and HB-1/3.9-inoculated pigs, using monoclonal antibodies to N and Nsp2 proteins. Conclusions Taken together, these findings indicate that the highly pathogenic PRRSV JXwn06 displays an expanded tissue tropism in vivo, suggesting this may contribute to its high pathogenicity to pigs.

2012-01-01

46

Potential radiotherapy improvements with respiratory gating  

Microsoft Academic Search

Gating is a relatively new and potentially useful therapeutic addition to external beam radiotherapy applied to regions affected\\u000a by intra-fraction motion. The impact was of gating on treatment margins, image artifacts, and volume and positional accuracy\\u000a was investigated by CT imaging of sinusoidally moving spheres. The motion of the spheres simulates target motion. During the\\u000a CT imaging of dynamically moving

P. J. Keall; V. R. Kini; S. S. Vedam; R. Mohan

2002-01-01

47

Complexes of potentially pathogenic microscopic fungi in anthropogenic polluted soils.  

PubMed

This study was undertaken to investigate the species' diversity and structure of potentially pathogenic microscopic fungal complexes in podzolic soils polluted by fluorine, heavy metals (Cu, Ni, Co), oil products (diesel fuel, gas condensate, mazut). Lists of potentially pathogenic fungi isolated from soils are made specifically for north-western part of Russia (Kola Peninsula). The majority of studied fungus species belong to the following genera: Penicillium, Aspergillus, Mucor, Lecanicillium and Phoma. Penicillium miczynskii was identified as the most stable type of fungus with respect to all studied types of oil products. Mucor hiemalis was identified as the most sensitive type. An increase of 15% portion of potentially pathogenic fungi as compared to the background soil in zones of aluminum and copper-nickel plants was revealed. The results indicate an increase of 20-25% of potentially pathogenic fungi in pollution of soil with oil products. The structure of fungal complexes was observed to have changed in the polluted soils and the species number and frequency of occurrence of potentially pathogenic fungi were also increased. PMID:23445417

Evdokimova, Galina A; Korneykova, Maria V; Lebedeva, Elena V

2013-01-01

48

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  

Microsoft Academic Search

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

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

2011-01-01

49

The Laboratory Diagnosis of Severe Acute Respiratory Syndrome: Emerging Laboratory Tests for an Emerging Pathogen  

PubMed Central

The 2003 pandemic of Severe Acute Respiratory Syndrome (SARS) profiled the ability of modern diagnostic microbiology and molecular biology to identify, isolate and characterize, within weeks, a previously unknown viral infectious pathogen. The culprit, SARS coronavirus (SARS-CoV), was detected in patient specimens by traditional cell culture using an unusual cell line for respiratory viruses, Vero E6, and by reverse transcriptase polymerase chain reaction (RT-PCR) targeting the polymerase 1 B region of the genome. In addition, serologic assays were rapidly developed, and the genome of this large virus was sequenced within one month of its spread to North America. At the present time, diagnostics have progressed to the point that RT-PCR has a sensitivity approaching 80% within the first few days of onset of illness, while serology has a sensitivity close to 100% on convalescent sera taken >21 days after illness onset. Viral culture remains a method confined to biosafety level III laboratories. The specificity of RT-PCR and serology remains to be conclusively defined, but in most studies to date seems to be >90%. Serologic cross-reactivity with human coronaviruses causing the common cold may be a problem with some serologic assays. The early development of SARS-CoV diagnostics is now being replaced by refinement and optimization of these assays. Although at the present time we do not have a test that will definitively rule in or rule out SARS at the time of initial presentation of a patient with a respiratory infection, modifications of existing assays will hopefully result in our ability to make this diagnosis with a high degree of accuracy in the future.

Richardson, Susan E.; Tellier, Raymond; Mahony, James

2004-01-01

50

Pathogenic characteristics of three genotype II porcine reproductive and respiratory syndrome viruses isolated from China  

PubMed Central

Background We examined differences in pathogenicity in pigs from China that had been experimentally infected with porcine reproductive and respiratory syndrome virus (PRRSV). Methods We compared pathogenic characteristics of a field isolate (GX-1/2008F), two PRRSV isolates (HN-1/2008, YN-1/2008) propagated in cells, and GX-1/2008F that had been propagated in cells (GX-1/2008). The clinical courses, along with humoral and cell-mediated responses, were monitored for 21 days post-infection (DPI). Animals were sacrificed and tissue samples used for gross pathological, histopathological and ultrastructure examination. Results At 2–3 DPI, animals infected with cell-propagated viruses exhibited signs of coughing, anorexia and fever. However their rectal temperature did not exceed 40.5°C. Viremia was detectable as early as 3 DPI in animals infected with HN-1/2008 and YN-1/2008. Animals inoculated with GX-1/2008F displayed clinical signs at 6 DPI; the rectal temperature of two animals in this group exceeded 41.0°C, with viremia first detected at 7 DPI. Seroconversion for all challenged pigs, except those infected with GX-1/2008, was seen as early as 7 DPI. All of these pigs had fully seroconverted by 11 DPI. All animals challenged with GX-1/2008 remained seronegative until the end of the experiment. Innate immunity was inhibited, with levels of IFN-? and IL-1 not significantly different between control and infected animals. The cytokines IFN-? and IL-6 transiently increased during acute infection. All virus strains caused gross lesions including multifocal interstitial pneumonia and hyperplasia of lymph nodes. Inflammation of the stomach and small intestine was also observed. Lesions in the group infected with GX-1/2008F were more serious than in other groups. Transmission electron microscopy revealed that alveolar macrophages, plasmacytes and lymphocytes had fractured cytomembranes, and hepatocytes had disrupted organelles and swollen mitochondria. Conclusions The pathogenicity of the PRRSV field isolate became attenuated when propagated in MARC-145 cells. Tissue tropism of highly pathogenic strains prevailing in China was altered compared with classical PRRSV strains. The observed damage to immune cells and modulation of cytokine production could be mechanisms that PRRSV employs to evade host immune responses.

2013-01-01

51

Pathogenic Potential of Novel Chlamydiae and Diagnostic Approaches to Infections Due to These Obligate Intracellular Bacteria  

PubMed Central

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 exibit 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.

Corsaro, Daniele; Greub, Gilbert

2006-01-01

52

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

PubMed Central

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 addition, provision of high-density SNP chips should make it possible to link phenotypes with genotypes in field populations without the need for structured populations or pedigree information. This will hopefully enable fine mapping of QTL and ultimate identification of the causal gene(s). The research could lead to selection of animals that are more resistant to disease and new ways to improve vaccine efficacy.

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

2012-01-01

53

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

PubMed

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 addition, provision of high-density SNP chips should make it possible to link phenotypes with genotypes in field populations without the need for structured populations or pedigree information. This will hopefully enable fine mapping of QTL and ultimate identification of the causal gene(s). The research could lead to selection of animals that are more resistant to disease and new ways to improve vaccine efficacy. PMID:21621277

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

2011-05-07

54

Rapid multiplex PCR assay to identify respiratory viral pathogens: moving forward diagnosing the common cold.  

PubMed

Upper respiratory tract infections (URIs) can be a serious burden to the healthcare system. The majority of URIs are viral in etiology, but definitive diagnosis can prove difficult due to frequently overlapping clinical presentations of viral and bacterial infections, and the variable sensitivity, and lengthy turn-around time of viral culture. We tested new automated nested multiplex PCR technology, the FilmArray(®) system, in the TAMC department of clinical investigations, to determine the feasibility of replacing the standard viral culture with a rapid turn-around system. We conducted a feasibility study using a single-blinded comparison study, comparing PCR results with archived viral culture results from a convenience sample of cryopreserved archived nasopharyngeal swabs from acutely ill ED patients who presented with complaints of URI symptoms. A total of 61 archived samples were processed. Viral culture had previously identified 31 positive specimens from these samples. The automated nested multiplex PCR detected 38 positive samples. In total, PCR was 94.5% concordant with the previously positive viral culture results. However, PCR was only 63.4% concordant with the negative viral culture results, owing to PCR detection of 11 additional viral pathogens not recovered on viral culture. The average time to process a sample was 75 minutes. We determined that an automated nested multiplex PCR is a feasible alternative to viral culture in an acute clinical setting. We were able to detect at least 94.5% as many viral pathogens as viral culture is able to identify, with a faster turn-around time. PMID:24052914

Layman, Clifton P; Gordon, Sarah M; Elegino-Steffens, Diane U; Agee, Willie; Barnhill, Jason; Hsue, Gunther

2013-09-01

55

Rapid Multiplex PCR Assay To Identify Respiratory Viral Pathogens: Moving Forward Diagnosing The Common Cold  

PubMed Central

Upper respiratory tract infections (URIs) can be a serious burden to the healthcare system. The majority of URIs are viral in etiology, but definitive diagnosis can prove difficult due to frequently overlapping clinical presentations of viral and bacterial infections, and the variable sensitivity, and lengthy turn-around time of viral culture. We tested new automated nested multiplex PCR technology, the FilmArray® system, in the TAMC department of clinical investigations, to determine the feasibility of replacing the standard viral culture with a rapid turn-around system. We conducted a feasibility study using a single-blinded comparison study, comparing PCR results with archived viral culture results from a convenience sample of cryopreserved archived nasopharyngeal swabs from acutely ill ED patients who presented with complaints of URI symptoms. A total of 61 archived samples were processed. Viral culture had previously identified 31 positive specimens from these samples. The automated nested multiplex PCR detected 38 positive samples. In total, PCR was 94.5% concordant with the previously positive viral culture results. However, PCR was only 63.4% concordant with the negative viral culture results, owing to PCR detection of 11 additional viral pathogens not recovered on viral culture. The average time to process a sample was 75 minutes. We determined that an automated nested multiplex PCR is a feasible alternative to viral culture in an acute clinical setting. We were able to detect at least 94.5% as many viral pathogens as viral culture is able to identify, with a faster turn-around time.

Gordon, Sarah M; Elegino-Steffens, Diane U; Agee, Willie; Barnhill, Jason; Hsue, Gunther

2013-01-01

56

Bioactive potential of Streptomyces against fish and shellfish pathogens  

PubMed Central

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 analysis yielded Rf values ranging from 0.40 to 0.78. Conclusion The results suggest that the seven Streptomyces strains isolated from marine sponges produce potential antibacterial compounds against fish and shellfish pathogens.

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

2010-01-01

57

Endobiotic bacteria and their pathogenic potential in cnidarian tentacles  

Microsoft Academic Search

Endobiotic bacteria colonize the tentacles of cnidaria. This paper provides first insight into the bacterial spectrum and\\u000a its potential of pathogenic activities inside four cnidarian species. Sample material originating from Scottish waters comprises\\u000a 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

Christian Schuett; Hilke Doepke

2010-01-01

58

Variable pathogenic potentials of mutations located in the desmin alpha-helical domain.  

PubMed

Mutations in the desmin gene have been recognized as a cause of desminopathy, a familial or sporadic disorder characterized by skeletal muscle weakness, often associated with cardiomyopathy or respiratory insufficiency. Distinctive histopathologic features include aberrant intracytoplasmic accumulation of desmin (DES). We present here comparative phenotypic, molecular, and functional characteristics of four novel and three previously reported, but not fully characterized, desmin mutations localized in desmin alpha-helical domain. The results indicate that the c.638C>T (p.A213V), c.1178A>T (p.N393I), and to some extent the c.1078G>C (p.A360P) mutations exhibit pathogenic potentials only if combined with other mutations in desmin or other genes and should therefore be considered conditionally pathogenic. The c.1009G>C (p.A337P), c.1013T>G (p.L338R), c.1195G>T (p.D399Y), and c.1201G>A (p.E401K) mutations make desmin filaments dysfunctional and are capable of causing disease. The pathogenic potentials of desmin mutations correlate with the type and location of the disease-associated mutations in the relatively large and structurally and functionally complex desmin molecule. Mutations within the highly conserved alpha-helical structures are especially damaging since the integrity of the alpha-helix is critical for desmin filament assembly and stability. PMID:16865695

Goudeau, Bertrand; Rodrigues-Lima, Fernando; Fischer, Dirk; Casteras-Simon, Monique; Sambuughin, Nyamkhishig; de Visser, Marianne; Laforet, Pascal; Ferrer, Xavier; Chapon, Françoise; Sjöberg, Gunnar; Kostareva, Anna; Sejersen, Thomas; Dalakas, Marinos C; Goldfarb, Lev G; Vicart, Patrick

2006-09-01

59

The FilmArray® respiratory panel: an automated, broadly multiplexed molecular test for the rapid and accurate detection of respiratory pathogens.  

PubMed

The FilmArray Respiratory Panel (RP) (BioFire(™) Diagnostics, Inc., Salt Lake City, UT, USA) is the first multiplex molecular panel cleared by the US FDA for the detection of both bacterial and viral respiratory pathogens in nasopharygeal swabs. The FilmArray RP targets 20 pathogens including 17 viruses and subtypes and three bacteria, and is performed with minimal sample manipulation. The FilmArray RP has a fully automated sample-to-answer workflow with a turn-around-time of approximately 1 h. The reported sensitivity and specificity of the assay ranges from 80 to 100 and 100%, respectively, with the sensitivity for the adenovirus as low as 46%. A new version of the FilmArray RP assay (version 1.7) with improved sensitivity for the adenovirus was released in 2013. The performance characteristics and simplified workflow have allowed its implementation in a wide range of laboratories. The FilmArray RP has changed the diagnostic landscape and will have a significant impact on the care of patients with respiratory tract infection. PMID:24151847

Babady, N Esther

2013-11-01

60

Potential for Palivizumab Interference With Commercially Available Antibody-antigen Based Respiratory Syncytial Virus Diagnostic Assays.  

PubMed

Palivizumab is a monoclonal antibody indicated for the prevention of serious lower respiratory tract disease caused by respiratory syncytial virus infection in infants. The potential for palivizumab to interfere with commercially available respiratory syncytial virus diagnostic tests was demonstrated. Negative test results in palivizumab-treated subjects should be interpreted with caution and confirmed by a nucleic acid amplification-based assay. PMID:23584584

Deming, Damon J; Patel, Nita; McCarthy, Michael P; Mishra, Lalji; Shapiro, Alan M; Suzich, Joann A

2013-10-01

61

[Proteolytic enzymes: potential allergens for the skin and respiratory tract?].  

PubMed

Proteolytic enzymes of animal, bacterial, mould or plant origin are used in many industrial processes, e.g. in the detergent, food and pharmaceutical industries as well as in medicine. The allergenic potency of these enzymes should not be underestimated, for they cause, in particular, IgE-mediated respiratory allergies. The risk of sensitization to enzymes due to inhalation as a result of occupational exposure is very high (up to 50%), and therapeutic applications are also not without risk. Therefore, the utmost care should be taken in the production and handling of pulverized enzymes and their inhalation should be avoided. Papain and Bromelain are used as tenderizers of meat and to clarify beer. Therefore, these enzymes are also potential ingestive allergens and may represent an unrecognized cause of an allergic reaction following a meal. As contact allergens the enzymes play a minor role; biodetergents in particular present no increased risk of skin damage for the user. PMID:3888919

Wüthrich, B

1985-03-01

62

Genome Sequence of Human Adenovirus Type 55, a Re-Emergent Acute Respiratory Disease Pathogen in China  

PubMed Central

Human adenovirus type 55 (HAdV-B55) is an acute respiratory disease (ARD) pathogen first completely characterized in China (2006). This is a unique Trojan horse microbe with the virus neutralization attribute of a renal pathogen and the cell tropism and clinical attributes of a respiratory pathogen, bypassing herd immunity. It appeared to be an uncommon pathogen, with earlier putative, sporadic occurrences in Spain (1969) and Turkey (2004); these isolates were incompletely characterized using only two epitopes. Reported here is the genome of a second recent isolate (China, 2011), indicating that it may occur more frequently. The availability of this HAdV-B55 genome provides a foundation for studying adenovirus molecular evolution, the dynamics of epidemics, and patterns of pathogen emergence and re-emergence. These data facilitate studies to predict genome recombination between adenoviruses, as well as sequence divergence rates and hotspots, all of which are important for vaccine development and because HAdVs are used for epitope and/or gene delivery vectors.

Seto, Donald; Cao, Bin; Zhao, Suhui

2012-01-01

63

Genome sequence of human adenovirus type 55, a re-emergent acute respiratory disease pathogen in China.  

PubMed

Human adenovirus type 55 (HAdV-B55) is an acute respiratory disease (ARD) pathogen first completely characterized in China (2006). This is a unique Trojan horse microbe with the virus neutralization attribute of a renal pathogen and the cell tropism and clinical attributes of a respiratory pathogen, bypassing herd immunity. It appeared to be an uncommon pathogen, with earlier putative, sporadic occurrences in Spain (1969) and Turkey (2004); these isolates were incompletely characterized using only two epitopes. Reported here is the genome of a second recent isolate (China, 2011), indicating that it may occur more frequently. The availability of this HAdV-B55 genome provides a foundation for studying adenovirus molecular evolution, the dynamics of epidemics, and patterns of pathogen emergence and re-emergence. These data facilitate studies to predict genome recombination between adenoviruses, as well as sequence divergence rates and hotspots, all of which are important for vaccine development and because HAdVs are used for epitope and/or gene delivery vectors. PMID:23087107

Zhang, Qiwei; Seto, Donald; Cao, Bin; Zhao, Suhui; Wan, Chengsong

2012-11-01

64

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

National Technical Information Service (NTIS)

Epidemic respiratory infections are responsible for extensive morbidity and mortality within both military and civilian populations. We describe a methodology to examine respiratory samples that simultaneously identifies broad groups of bacteria. The proc...

D. J. Ecker R. Sampath L. B. Blyn V. Samant K. Russell

2003-01-01

65

In vitro activity of moxifloxacin(BAY 12-8039) against respiratory tract pathogens from six Latin-American countries.  

PubMed

The in vitro antibacterial activity of moxifloxacin (BAY 12-8039) was evaluated against 636 isolates of respiratory tract pathogens. The isolates were collected from July 1997 to August 1998 in the frame of a multinational Latin American study. E-test strips calibrated to read moxifloxacin MIC ranges from 0.002 to 32 microg/ml were used in susceptibility testing. Weekly quality control tests in each laboratory ensured reproducibility. Laboratories from Argentina, Brazil, Chile, Colombia, Mexico and Uruguay participated. MIC(90) for moxifloxacin were as follows: Streptococcus pneumoniae (304 isolates) 0.25 microg/ml, Haemophilus influenzae (135 isolates) 0.125 microg/ ml, Streptococcus pyogenes (66 isolates) 0.25 microg/ml, Moraxella catarrhalis (62 isolates) 0. 25 microg/ml and methicillin-sensitive Staphylococcus aureus (69 isolates) 0.25 microg/ml. These results agreed with reports from other areas. Moxifloxacin showed excellent activity against respiratory pathogens from participant countries. PMID:11053902

Cardeñosa G, O; Soto-Hernández, J L

66

Rethinking biosafety in research on potential pandemic pathogens.  

PubMed

If accidentally released, mammalian-transmissible influenza A/H5N1 viruses could pose a greater threat to public health than possibly any other infectious agent currently under study in laboratories, because of such viruses' likely combination of transmissibility and virulence to humans. We advocate explicit risk-benefit assessments before work on such pathogens is permitted or funded, improvement of biosafety practices and enforcement, and harmonization of criteria for permitting such experiments across government agencies, as well as internationally. Such potential pandemic pathogens, as they have been called, jeopardize not only laboratory workers and their contacts, but also the wider population, who should be involved in assessments of when such risks are acceptable in the service of scientific knowledge that may itself bear major public health benefits. PMID:23047752

Lipsitch, Marc; Bloom, Barry R

2012-10-09

67

Comparative in vitro Activity of S-4661, a New Parenteral Carbapenem, and Other Antimicrobial Agents against Respiratory Pathogens  

Microsoft Academic Search

The activity of S-4661, a new parenteral carbapenem antibiotic, was evaluated against 202 recent clinical isolates of respiratory pathogens. S-4661 was similar to or 2 times more active than imipenem, meropenem, and biapenem, and 8–128 times more active than ceftazidime against gram-positive bacteria. Against gram-negative bacteria, S-4661 was slightly less active than meropenem, but 2–8 times more active than the

Akira Watanabe; Hiroshi Takahashi; Tohru Kikuchi; Takao Kobayashi; Kazunori Gomi; Shigeru Fujimura; Yutaka Tokue; Toshihiro Nukiwa

2000-01-01

68

Reverse transcription loop-mediated isothermal amplification for the detection of highly pathogenic porcine reproductive and respiratory syndrome virus  

Microsoft Academic Search

A reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay targeting the open reading frames 1a of highly pathogenic porcine reproductive and respiratory syndrome virus genome was developed. The 10 reference strains, 1 clinical isolation strain and 122 positive samples were tested. Positive reactions were confirmed for all strains and specimens by reverse transcription loop-mediated isothermal amplification and nested reverse transcription polymerase

Hao-tai Chen; Jie Zhang; De-hui Sun; Li-na Ma; Xiang-tao Liu; Kai Quan; Yong-sheng Liu

2008-01-01

69

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

SciTech Connect

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.

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

2007-04-11

70

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

PubMed

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 ?-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. PMID:20839026

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

2010-09-14

71

Isolation, propagation, and characterization of a newly recognized pathogen, cilia-associated respiratory bacillus of rats, an etiological agent of chronic respiratory disease.  

PubMed Central

A Gram-negative, filamentous, rod-shaped bacillus which failed to grow in cell-free media was isolated in apparently pure culture from the bronchial scraping and washing of a laboratory rat suffering from chronic respiratory disease by inoculating embryonated chicken eggs via the allantoic route. None of the embryos died during 20 serial passages at weekly intervals. The bacillus was reisolated in embryonated eggs from cesarean-derived barrier-maintained N:SD(SD) rats 8 and 12 weeks after intranasal inoculation with 10th-passage allantoic fluid. The inoculated rats were housed in Horsfall-type units and remained free from other known respiratory pathogens, including mycoplasmas and murine viruses, throughout the study. The bacillus colonized the ciliated epithelial cells of the respiratory tract and caused a marked peribronchial infiltration and hyperplasia of mononuclear cells which progressed with time. The bacillus, ca. 0.2 micron wide by 4 to 6 micron long, stained very poorly with basic aniline dyes but was readily demonstrated with the Warthin-Starry silver technique. It was heat labile (56 degrees C for 30 min); spore forms were not observed. It withstood freeze-thawing and was successfully stored at -70 degrees C. Although no visible means of locomotion was observed with the electron microscope, a slow gliding motility, sometimes with bending and flexing of bacilli apparently adherent to the glass surface, was observed with phase microscopy. As an etiological agent of chronic respiratory disease of rats, this cilia-associated respiratory bacillus (tentatively designated the CAR bacillus) may be the first recognized gliding bacterium known to cause disease in a warm-blooded vertebrate. Images

Ganaway, J R; Spencer, T H; Moore, T D; Allen, A M

1985-01-01

72

Upper respiratory tract microbial communities, acute otitis media pathogens, and antibiotic use in healthy and sick children.  

PubMed

The composition of the upper respiratory tract microbial community may influence the risk for colonization by the acute otitis media (AOM) pathogens Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. We used culture-independent methods to describe upper respiratory tract microbial communities in healthy children and children with upper respiratory tract infection with and without concurrent AOM. Nasal swabs and data were collected in a cross-sectional study of 240 children between 6 months and 3 years of age. Swabs were cultured for S. pneumoniae, and real-time PCR was used to identify S. pneumoniae, H. influenzae, and M. catarrhalis. The V1-V2 16S rRNA gene regions were sequenced using 454 pyrosequencing. Microbial communities were described using a taxon-based approach. Colonization by S. pneumoniae, H. influenzae, and M. catarrhalis was associated with lower levels of diversity in upper respiratory tract flora. We identified commensal taxa that were negatively associated with colonization by each AOM bacterial pathogen and with AOM. The balance of these relationships differed according to the colonizing AOM pathogen and history of antibiotic use. Children with antibiotic use in the past 6 months and a greater abundance of taxa, including Lactococcus and Propionibacterium, were less likely to have AOM than healthy children (odds ratio [OR], 0.46; 95% confidence interval [CI], 0.25 to 0.85). Children with no antibiotic use in the past 6 months, a low abundance of Streptococcus and Haemophilus, and a high abundance of Corynebacterium and Dolosigranulum were less likely to have AOM (OR, 0.51; 95% CI, 0.31 to 0.83). An increased understanding of polymicrobial interactions will facilitate the development of effective AOM prevention strategies. PMID:22752171

Pettigrew, Melinda M; Laufer, Alison S; Gent, Janneane F; Kong, Yong; Fennie, Kristopher P; Metlay, Joshua P

2012-06-29

73

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

PubMed

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. PMID:17189093

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

2007-01-01

74

The bioactivity of plant extracts against representative bacterial pathogens of the lower respiratory tract  

Microsoft Academic Search

BACKGROUND: Lower respiratory tract infections are a major cause of illness and death. Such infections are common in intensive care units (ICU) and their lethality persists despite advances in diagnosis, treatment and prevention. In Mexico, some plants are used in traditional medicine to treat respiratory diseases or ailments such as cough, bronchitis, tuberculosis and other infections. Medical knowledge derived from

Virgilio Bocanegra-García; María del Rayo Camacho-Corona; Mónica Ramírez-Cabrera; Gildardo Rivera; Elvira Garza-González

2009-01-01

75

Analysis of the swine tracheobronchial lymphnode transcriptomic response to infection with a Chinese highly pathogenic strain of porcine reproductive and respiratory syndrome virus  

Technology Transfer Automated Retrieval System (TEKTRAN)

Porcine reproductive and respiratory syndrome virus (PRRSV) is a major pathogen of swine worldwide. Emergence in 2006 of a novel highly pathogenic PRRSV (HP-PRRSV) isolate in China necessitated a comparative investigation into the host transcriptome response in tracheobronchial lymph nodes (TBLN) 14...

76

Secondary infection with Streptococcus suis serotype 7 increases the virulence of highly pathogenic porcine reproductive and respiratory syndrome virus in pigs  

Microsoft Academic Search

BACKGROUND: Porcine reproductive and respiratory syndrome virus (PRRSV) and Streptococcus suis are common pathogens in pigs. In samples collected during the porcine high fever syndrome (PHFS) outbreak in many parts of China, PRRSV and S. suis serotype 7 (SS7) have always been isolated together. To determine whether PRRSV-SS7 coinfection was the cause of the PHFS outbreak, we evaluated the pathogenicity

Min Xu; Shujie Wang; Linxi Li; Liancheng Lei; Yonggang Liu; Wenda Shi; Jiabin Wu; Liqin Li; Fulong Rong; Mingming Xu; Guangli Sun; Hua Xiang; Xuehui Cai

2010-01-01

77

Potentially pathogenic acanthamoeba isolated from a hospital in Brazil.  

PubMed

Studies on free-living amoebae (FLA), has been increased in recent years, especially related to the genus Acanthamoeba, because these organisms are widely found in the environment. The present work isolated and characterized this organism from biofilms and dust in hospital environment. 135 samples were collected in 15 different environments in a hospital at the south of Brazil. Thirty-one (23%) isolates were identified as morphologically belonging to the Acanthamoeba genus and 10 of these were submitted to temperature and osmotolerance tests as criterion for evaluation of the viability and pathogenicity. The tests indicate that four (40%) of these isolates could be potentially pathogenic because grew at high temperature (40 degrees C) and osmolarity (mannitol 1 M). Some isolates genotypes were determined after ribosomal DNA sequencing. These data revealed that three dust isolates belong to T4, two biofilm isolates to T5 and one dust isolate to T3 genotype. Therefore, Acanthamoeba found in the hospital environment represents a risk for people that circulate there. PMID:19841975

Carlesso, Ana Maris; Artuso, Geórgia Lazzari; Caumo, Karin; Rott, Marilise Brittes

2009-10-20

78

Mediterranean Fruit Fly as a Potential Vector of Bacterial Pathogens  

PubMed Central

The Mediterranean fruit fly (Ceratitis capitata) is a cosmopolitan pest of hundreds of species of commercial and wild fruits. It is considered a major economic pest of commercial fruits in the world. Adult Mediterranean fruit flies feed on all sorts of protein sources, including animal excreta, in order to develop eggs. After reaching sexual maturity and copulating, female flies lay eggs in fruit by puncturing the skin with their ovipositors and injecting batches of eggs into the wounds. In view of the increase in food-borne illnesses associated with consumption of fresh produce and unpasteurized fruit juices, we investigated the potential of Mediterranean fruit fly to serve as a vector for transmission of human pathogens to fruits. Addition of green fluorescent protein (GFP)-tagged Escherichia coli to a Mediterranean fruit fly feeding solution resulted in a dose-dependent increase in the fly's bacterial load. Flies exposed to fecal material enriched with GFP-tagged E. coli were similarly contaminated and were capable of transmitting E. coli to intact apples in a cage model system. Washing contaminated apples with tap water did not eliminate the E. coli. Flies inoculated with E. coli harbored the bacteria for up to 7 days following contamination. Fluorescence microscopy demonstrated that the majority of fluorescent bacteria were confined along the pseudotrachea in the labelum edge of the fly proboscis. Wild flies captured at various geographic locations were found to carry coliforms, and in some cases presumptive identification of E. coli was made. These findings support the hypothesis that the common Mediterranean fruit fly is a potential vector of human pathogens to fruits.

Sela, Shlomo; Nestel, David; Pinto, Riky; Nemny-Lavy, Esther; Bar-Joseph, Moshe

2005-01-01

79

Endobiotic bacteria and their pathogenic potential in cnidarian tentacles  

NASA Astrophysics Data System (ADS)

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 the production of cytotoxins, tetrodotoxin and R-toxin. Findings of haemolysis tests support the literature data. The potential producers are Endozoicimonas elysicola, Moritella viscosa, Photobacterium profundum, P. aliena, P. tetraodonis, Shewanella waksmanii, Vibrio splendidus, V. aestuarius, Arcobacter butzleri.

Schuett, Christian; Doepke, Hilke

2010-09-01

80

Collagen VI Is a Subepithelial Adhesive Target for Human Respiratory Tract Pathogens  

Microsoft Academic Search

Bacterial engagement of specific host tissue structures can be a means of targeting a pathogen to a particular niche, establishing persistent infections and inducing invasion. In this context, primary adhesion is often the first crucial colonization step allowing pathogens to withstand the mechanical clearing mechanisms of the host. As a consequence, bacteria have evolved adhesins with the capacity to mediate

Marta Bober; Charlotte Enochsson; Mattias Collin; Matthias Mörgelin

2010-01-01

81

Antimicrobial activity of prulifloxacin in comparison with other fluoroquinolones against community-acquired urinary and respiratory pathogens isolated in Greece.  

PubMed

Prulifloxacin, the prodrug of ulifloxacin, is a broad-spectrum fluoroquinolone rather recently introduced in certain European countries. We compared the antimicrobial potency of ulifloxacin with that of other fluoroquinolones against common urinary and respiratory bacterial pathogens. The microbial isolates were prospectively collected between January 2007 and May 2008 from patients with community-acquired infections in Greece. Minimum inhibitory concentrations (MICs) were determined for ciprofloxacin, levofloxacin, moxifloxacin (for respiratory isolates only), and ulifloxacin using the E-test method. The binary logarithms of the MICs [log2(MICs)] were compared by using the Wilcoxon signed-ranks test. A total of 409 isolates were studied. Ulifloxacin had the lowest geometric mean MIC for the 161 Escherichia coli, 59 Proteus mirabilis, and 22 Staphylococcus saprophyticus urinary isolates, the second lowest geometric mean MIC for the 38 Streptococcus pyogenes respiratory isolates (after moxifloxacin), and the third lowest geometric mean MIC for the 114 Haemophilus influenzae and the 15 Moraxella catarrhalis respiratory isolates (after ciprofloxacin and moxifloxacin). Compared with levofloxacin, ulifloxacin had lower log2(MICs) against E. coli (p?respiratory isolates. PMID:23686506

Karageorgopoulos, D E; Maraki, S; Vatopoulos, A C; Samonis, G; Schito, G C; Falagas, M E

2013-05-19

82

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...

83

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...

84

In Vivo Activity of HSR-903, a New Fluoroquinolone, against Respiratory Pathogens  

PubMed Central

The in vivo activity of HSR-903, a new fluoroquinolone, against major bacteria which cause respiratory tract infections was evaluated. HSR-903 was active against experimental respiratory tract infections in mice challenged with penicillin-susceptible and penicillin-resistant Streptococcus pneumoniae and Haemophilus influenzae strains. Treatment with HSR-903 reduced the bacterial numbers in infected murine lungs. In accord with the pulmonary clearance results, the rates of survival for mice treated with HSR-903, sparfloxacin, levofloxacin, ciprofloxacin, and benzylpenicillin were 50, 30, 10, 0, and 0%, respectively, 14 days after being infected with penicillin-resistant S. pneumoniae. A pharmacokinetic study with pneumonic mice showed that the levels of HSR-903 in the lungs were seven to eight times higher than those in the plasma. These results indicate that clinical studies of HSR-903 against respiratory tract infections may be warranted.

Yoshizumi, Satoshi; Domon, Haruki; Miyazaki, Shuichi; Yamaguchi, Keizo

1998-01-01

85

Isolation of antibiotic-resistant pathogenic and potentially pathogenic bacteria from carpets of mosques in Tripoli, Libya  

PubMed Central

Objective Isolation of potentially pathogenic bacteria from carpets in hospitals has been reported earlier, but not from carpets in mosques. The aim of the present study is to determine the pathogenic and potentially pathogenic bacteria that may exist on the carpets of mosques in Tripoli, Libya. Methods Dust samples from carpets were collected from 57 mosques in Tripoli. Samples were examined for pathogenic bacteria using standard bacteriological procedures. Susceptibility of isolated bacteria to antimicrobial agents was determined by the disc-diffusion method. Results Of dust samples examined, Salmonella spp. was detected in two samples (3.5%, 1 in group B and 1 in group C1), Escherichia coli in 16 samples (28.1%), Aeromonas spp. in one sample (1.8%), and Staphylococcus aureus in 12 samples (21.1%). Multiple drug resistance was observed in >16.7% of E. coli and in 25% of S. aureus. Conclusion Contamination of carpets in mosques of Tripoli with antibiotic-resistant pathogenic and potentially pathogenic bacteria may pose a health risk to worshipers, particularly, the very young, the old and the immunecompromised. Worshipers are encouraged to use personal praying mats when praying in mosques.

Rahouma, Amal; Elghamoudi, Abdunabi; Nashnoush, Halima; Belhaj, Khalifa; Tawil, Khaled; Sifaw Ghenghesh, Khalifa

2010-01-01

86

LOW PATHOGENIC POTENTIAL IN HETEROTROPHIC BACTERIA FROM POTABLE WATER  

EPA Science Inventory

Forty-five isolates of HPC bacteria, most of which express virulence-related characteristics are being tested for pathogenicity in immunocompromised mice. All forty-five were negative for facultative intracellular pathogenicity. All twenty-three isolates tested thus far were a...

87

Dynamic changes in inflammatory cytokines in pigs infected with highly pathogenic porcine reproductive and respiratory syndrome virus.  

PubMed

Porcine reproductive and respiratory syndrome virus (PRRSV) infection induces both humoral and cellular immune responses. In this study, we investigated the changes in cytokine levels in peripheral blood between the highly pathogenic PRRSV HuN4 strain and its derivative strain HuN4-F112 obtained by serial propagation in MARC145 cells to 112 passages. The results demonstrated that pigs infected with HuN4 showed a loss of appetite, decrease in body weight, raised body temperature, and respiratory symptoms, along with interstitial pneumonia lesions. The PRRSV amounts in the pigs infected with HuN4 were 10(5) to 10(9) copies/ml in the blood and 10(10) to 10(11) copies/g in the lung tissues, whereas the virus amounts with HuN4-F112 were 10(2.15) to 10(3.13) copies/ml in the blood and 10(3.0) to 10(3.6) copies/g in the lungs. Moreover, the levels of interleukin 1 (IL-1), IL-6, tumor necrosis factor alpha (TNF-alpha), and alpha interferon (IFN-alpha) in peripheral blood were upregulated 7 days postinoculation with HuN4, which was earlier than in the HuN4-F112 group. Furthermore, cytokine levels in the pigs infected with HuN4 returned to normal on the 21st day postinoculation, while the levels in those infected with HuN4-F112 continued to increase. These results demonstrated that the pigs infected with the highly pathogenic PRRSV HuN4 strain generated earlier and higher levels of inflammatory cytokines, and the results also indicated that HuN4 may aggravate inflammation and damage tissues and organs. The low-pathogenic PRRSV HuN4-F112 strain induced lower levels of inflammatory cytokines, which may enhance the immune responses against the infection. PMID:20631336

Liu, Yonggang; Shi, Wenda; Zhou, Enmin; Wang, Shujie; Hu, Shouping; Cai, Xuehui; Rong, Fulong; Wu, Jiabin; Xu, Min; Xu, Mingming; Li, Liqin

2010-07-14

88

Assessment of allergic potential of chemicals for respiratory allergy  

Microsoft Academic Search

At least 10% of the population of the western world is suffering from\\u000arespiratory syndromes with characteristics of asthma or COPD (Chronic\\u000aObstructive Pulmonary Disease). In addition to inheritable components,\\u000ait is well known that exaggerated immune responses against inhaled\\u000acompounds can lead to respiratory allergy. More than 50% of the number\\u000aof asthma cases are induced by type I

Garssen J; Loveren H van

2007-01-01

89

Unaltered respiratory-related evoked potentials after acute diaphragm dysfunction in humans.  

PubMed

Respiratory muscles play an important role in the origin of respiratory sensations. Data dissecting the role of the diaphragm and other inspiratory muscles are scarce. This study aimed to determine the impact of diaphragm dysfunction following inspiratory resistive loading on respiratory-related evoked potentials considered as a neurophysiological substrate of certain types of respiratory sensations. Altogether, nine subjects aged 25-50 yrs (six females) participated in the study. Transdiaphragmatic pressure output of cervical magnetic stimulation (with subdivision in oesophageal and gastric component), and respiratory-related evoked potentials (C3 and C4 derivations in the international 10-20 system) following mid-inspiratory occlusions were studied before and after an inspiratory-resistive loading challenge. Predominant diaphragm dysfunction was observed in seven subjects (average 28% reduction in transdiaphragmatic pressure, from 27.25-19.91 cmH2O, with increased oesophageal-to-gastric pressure ratio). The latencies and amplitudes of all the components of the respiratory-related evoked potentials were unchanged. The study concluded that predominant diaphragm fatigue does not affect respiratory-related evoked potentials. PMID:14582915

Bezzi, M; Donzel-Raynaud, C; Straus, C; Tantucci, C; Zelter, M; Derenne, J P; Similowski, T

2003-10-01

90

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 ...

91

Real-time electronic nose based pathogen detection for respiratory intensive care patients  

Microsoft Academic Search

An acoustic wave based electronic nose was used to monitor the exhaled breath of patients in an intensive care unit. The system could be used for detecting and identifying bacterial infections of the lungs and airways in real-time. The patients all had ventilator assisted breathing and were diagnosed with respiratory failure due to severe pneumonia and other extrapulmonary diseases by

Chung-Hung Shih; Yuh-Jiuan Lin; Kun-Feng Lee; Pei-Yu Chien; Philip Drake

2010-01-01

92

Rates of antimicrobial resistance among common bacterial pathogens causing respiratory, blood, urine, and skin and soft tissue infections in pediatric patients  

Microsoft Academic Search

Antimicrobial resistance patterns among the principal bacterial pathogens from infections of the respiratory tract, blood, skin and soft tissue, and urinary tract of pediatric patients from the USA, Canada, Germany, France, and Italy were studied using the The Surveillance Network (TSN) database. Among Streptococcus pneumoniae isolates from respiratory tract infections, the prevalence of high-level penicillin resistance (MIC=2 µg\\/ml) ranged from 1.1

M. E. Jones; J. A. Karlowsky; D. C. Draghi; C. Thornsberry; D. F. Sahm; J. S. Bradley

2004-01-01

93

Potential pathogenic bacteria in metalworking fluids and aerosols from a machining facility.  

PubMed

The metalworking and machining industry utilizes recirculating metalworking fluids for integral aspects of the fabrication process. Despite the use of biocides, these fluids sustain substantial biological growth. Subsequently, the high-shear forces incurred during metalworking processing aerosolize bacterial cells and may cause dermatologic and respiratory effects in exposed workers. We quantified and identified the bacterial load for metalworking fluid and aerosol samples of a machining facility in the US Midwest during two seasons. To investigate the presence of potentially pathogenic bacteria in fluid and air, we performed 16S rRNA gene surveys. The concentration of total bacterial cells (including culturable and nonculturable cells) was relatively constant throughout the study, averaging 5.1 × 10? cells mL?¹ in the fluids and 4.8 × 10? cells m?³ in the aerosols. We observed bacteria of potential epidemiologic significance from several different bacterial phyla in both fluids and aerosols. Most notably, Alcaligenes faecalis was identified through both direct sequencing and culturing in every sample collected. Elucidating the bacterial community with gene surveys showed that metalworking fluids were the source of the aerosolized bacteria in this facility. PMID:20955193

Perkins, Sarah D; Angenent, Largus T

2010-10-18

94

The complete genome sequence of the murine respiratory pathogen Mycoplasma pulmonis  

Microsoft Academic Search

Mycoplasma pulmonis is a wall-less eubacterium belonging to the Mollicutes (trivial name, myco- plasmas) and responsible for murine respiratory diseases. The genome of strain UAB CTIP is composed of a single circular 963 879 bp chromosome with a G + C content of 26.6 mol%, i.e. the lowest reported among bacteria, Ureaplasma urealyticum apart. This genome contains 782 putative coding

Isabelle Chambaud; Roland Heilig; Stéphane Ferris; Valérie Barbe; Delphine Samson; Frédérique Galisson; I van Moszer; Kevin Dybvig; Henri Wróblewski; Alain Viari; Eduardo P. C. Rocha; Alain Blanchard

2001-01-01

95

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

PubMed

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. PMID:21850204

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

2011-08-07

96

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...

97

In vitro Microbiological Characterization of a Novel Azalide, Two Triamilides and an Azalide Ketal Against Bovine and Porcine Respiratory Pathogens  

Microsoft Academic Search

Several novel 15-membered-ring macrolide agents (azalide 1, triamilides 2 and 3, and the azalide 3,6-ketal 4) were identified as potential antibacterial agents against Mannheimia (formerly named as Pasteurella) haemolytica, Pasteurella multocida, Haemophilus somnus and Actinobacillus pleuropneumoniae, important etiological agents of bovine and porcine respiratory disease. Compound 3 is the major component of the antibiotic tulathromycin. Antibacterial activity against tilmicosin-resistant P.

Laura J. L. Norcia; Annette M. Silvia; Sheryl L. Santoro; Jim Retsema; Michael A. Letavic; Brian S. Bronk; Kristin M. Lundy; Bingwei Yang; Nigel A. Evans; Shigeru F. Hayashi

2004-01-01

98

Demonstration of the metaphylactic use of gamithromycin against bacterial pathogens associated with bovine respiratory disease in a multicentre farm trial  

PubMed Central

On five commercial cattle rearing sites across Europe, a total of 802 young cattle at high risk of developing bovine respiratory disease (BRD) associated with the bacterial pathogens Mannheimia haemolytica or Pasteurella multocida and/or Mycoplasma bovis were enrolled into a multicentre, controlled field trial. Half were treated with a single dose of gamithromycin at 6 mg/kg bodyweight by subcutaneous injection and half received an injection of a saline placebo as the control. All animals were observed daily for 14 days for signs of BRD as defined by set criteria. The proportion of metaphylactic preventive treatment successes, defined as animals surviving to day 14 without signs of BRD, in the gamithromycin-treated group (86 per cent) was significantly (P=0.0012) higher than in the saline-treated controls (61 per cent). Morbidity among the treated animals was reduced by 64 per cent compared with the controls.

Baggott, D.; Casartelli, A.; Fraisse, F.; Manavella, C.; Marteau, R.; Rehbein, S.; Wiedemann, M.; Yoon, S.

2011-01-01

99

FilmArray, an Automated Nested Multiplex PCR System for Multi-Pathogen Detection: Development and Application to Respiratory Tract Infection  

PubMed Central

The ideal clinical diagnostic system should deliver rapid, sensitive, specific and reproducible results while minimizing the requirements for specialized laboratory facilities and skilled technicians. We describe an integrated diagnostic platform, the “FilmArray”, which fully automates the detection and identification of multiple organisms from a single sample in about one hour. An unprocessed biologic/clinical sample is subjected to nucleic acid purification, reverse transcription, a high-order nested multiplex polymerase chain reaction and amplicon melt curve analysis. Biochemical reactions are enclosed in a disposable pouch, minimizing the PCR contamination risk. FilmArray has the potential to detect greater than 100 different nucleic acid targets at one time. These features make the system well-suited for molecular detection of infectious agents. Validation of the FilmArray technology was achieved through development of a panel of assays capable of identifying 21 common viral and bacterial respiratory pathogens. Initial testing of the system using both cultured organisms and clinical nasal aspirates obtained from children demonstrated an analytical and clinical sensitivity and specificity comparable to existing diagnostic platforms. We demonstrate that automated identification of pathogens from their corresponding target amplicon(s) can be accomplished by analysis of the DNA melting curve of the amplicon.

Poritz, Mark A.; Blaschke, Anne J.; Byington, Carrie L.; Meyers, Lindsay; Nilsson, Kody; Jones, David E.; Thatcher, Stephanie A.; Robbins, Thomas; Lingenfelter, Beth; Amiott, Elizabeth; Herbener, Amy; Daly, Judy; Dobrowolski, Steven F.; Teng, David H. -F.; Ririe, Kirk M.

2011-01-01

100

Novel Antibiotics Targeting Respiratory ATP Synthesis in Gram-Positive Pathogenic Bacteria  

PubMed Central

Emergence of drug-resistant bacteria represents a high, unmet medical need, and discovery of new antibacterials acting on new bacterial targets is strongly needed. ATP synthase has been validated as an antibacterial target in Mycobacterium tuberculosis, where its activity can be specifically blocked by the diarylquinoline TMC207. However, potency of TMC207 is restricted to mycobacteria with little or no effect on the growth of other Gram-positive or Gram-negative bacteria. Here, we identify diarylquinolines with activity against key Gram-positive pathogens, significantly extending the antibacterial spectrum of the diarylquinoline class of drugs. These compounds inhibited growth of Staphylococcus aureus in planktonic state as well as in metabolically resting bacteria grown in a biofilm culture. Furthermore, time-kill experiments showed that the selected hits are rapidly bactericidal. Drug-resistant mutations were mapped to the ATP synthase enzyme, and biochemical analysis as well as drug-target interaction studies reveal ATP synthase as a target for these compounds. Moreover, knockdown of the ATP synthase expression strongly suppressed growth of S. aureus, revealing a crucial role of this target in bacterial growth and metabolism. Our data represent a proof of principle for using the diarylquinoline class of antibacterials in key Gram-positive pathogens. Our results suggest that broadening the antibacterial spectrum for this chemical class is possible without drifting off from the target. Development of the diarylquinolines class may represent a promising strategy for combating Gram-positive pathogens.

Balemans, Wendy; Vranckx, Luc; Lounis, Nacer; Pop, Ovidiu; Guillemont, Jerome; Vergauwen, Karen; Mol, Selena; Gilissen, Ron; Motte, Magali; Lancois, David; De Bolle, Miguel; Bonroy, Kristien; Lill, Holger; Andries, Koen

2012-01-01

101

Field efficacy of combination vaccines against bovine respiratory pathogens in calves.  

PubMed

The efficacy of an inactivated bovine respiratory syncytial virus (BRSV)--bovine parainfluenza type 3 (PI3)--Mannheimia haemolytica (Mh) combination vaccine was examined in two field studies. Calves were vaccinated (i) with the inactivated vaccine, (ii) a modified live/killed viral combination vaccine, or (iii) left unvaccinated. The efficacy of the vaccines was judged by the (i) number of treated animals, (ii) number of individual antibiotic treatments per calf and (iii) mortality rates. After vaccination with the inactivated vaccine, the number of calves requiring antibiotic treatment was significantly lower than in the unvaccinated group (odds ratios: 0.26 first study and 0.53 second study), but differences between vaccination with live/killed combination vaccines and controls were not significant (odds ratios: 0.56 and 0.90, respectively). In both studies, a number of unvaccinated controls died due to respiratory disease (4.6% first and 6.7% second study). By contrast, none of the animals vaccinated with the inactivated vaccine died in the first study and only 3.3% in the second study. The mortality rates for the groups vaccinated with the live vaccine (1.3% and 7.8%) were similar to the unvaccinated controls. In summary, these data demonstrate the efficacy of the inactivated vaccine under field conditions. PMID:19149103

Makoschey, Birgit; Bielsa, Juan Muñoz; Oliviero, Loïc; Roy, Olivier; Pillet, Florence; Dufe, Divine; Valla, Giorgio; Cavirani, Sandro

2008-12-01

102

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

PubMed

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. PMID:21257416

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

2010-10-01

103

The Alexander Project 1998-2000: susceptibility of pathogens isolated from community-acquired respiratory tract infection to commonly used antimicrobial agents  

Microsoft Academic Search

Objectives: The Alexander Project is a continuing surveillance study, begun in 1992, examining the suscep- tibility of pathogens involved in adult community-acquired respiratory tract infections (CARTI) to a range of antimicrobial agents. Materials and methods: This study tested the susceptibility of isolates of Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis collected between 1998 and 2000 to 23 antimicrobials. Minimum inhibitory

Michael R. Jacobs; David Felmingham; Peter C. Appelbaum; Reuben N. Grüneberg

104

Telomere components as potential therapeutic targets for treating microbial pathogen infections  

PubMed Central

In a number of microbial pathogens that undergoes antigenic variation to evade the host’s immune attack, genes encoding surface antigens are located at subtelomeric loci, and recent studies have revealed that telomere components play important roles in regulation of surface antigen expression in several of these pathogens, indicating that telomeres play critical roles in microbial pathogen virulence regulation. Importantly, although telomere protein components and their functions are largely conserved from protozoa to mammals, telomere protein homologs in microbial pathogens and humans have low sequence homology. Therefore, pathogen telomere components are potential drug targets for therapeutic approaches because first, most telomere proteins are essential for pathogens’ survival, and second, disruption of pathogens’ antigenic variation mechanism would facilitate host’s immune system to clear the infection.

Li, Bibo

2012-01-01

105

Respiratory Viruses Augment the Adhesion of Bacterial Pathogens to Respiratory Epithelium in a Viral Species and Cell Type-Dependent Manner  

Microsoft Academic Search

Secondary bacterial infections often complicate respiratory viral infections, but the mechanisms whereby viruses predispose to bacterial disease are not completely understood. We determined the effects of infection with respiratory syncytial virus (RSV), human parainfluenza virus 3 (HPIV-3), and influenza virus on the abilities of nontypeable Haemophilus influenzae and Streptococcus pneumoniae to adhere to respiratory epithelial cells and how these viruses

Vasanthi Avadhanula; Carina A. Rodriguez; John P. DeVincenzo; Yan Wang; Richard J. Webby; Glen C. Ulett; Elisabeth E. Adderson

2006-01-01

106

Development of a new resequencing pathogen microarray based assay for detection of broad-spectrum respiratory tract viruses in patients with community-acquired pneumonia.  

PubMed

A Resequencing Pathogen Microarray (RPM) is a single, highly multiplexed assay for detecting and differentiating similarly related pathogens by using closely overlapping probe sets to determine a target organism's nucleotide sequence. In this study, a new RPM (RPM-IVDC1) that consisted of 224-bp detector tiles corresponding to 9 influenza A subtypes, 11 rhinoviruses, 28 enteroviruses and 38 other respiratory viruses was developed and optimized to provide individual and simultaneous detection sensitivities ranging from 15 to 750 genomic copies for 16 common respiratory pathogens. A total of 110 consecutive patients with community-acquired pneumonia (CAP) admitted to 5 district general hospitals in Beijing during a 1-year period were assessed using the new assay. Among the children (under age 5) and adult patients (above age 18), respiratory syncytial virus (RSV) and rhinovirus (RV) were the most common etiological agents, respectively, which is consistent with reference assays. Atypical pathogens that may cause CAP-like illness, including rubella virus, measles virus, influenza type C virus, human herpesvirus (HHV) were also detected. The results show the capability of RPM-IVDC1 for the accurate detection and identification of multiple virus types, which may be of significant use in epidemic surveillance and outbreak investigations of atypical pathogens. PMID:24086618

Shen, Hongwei; Shi, Weixian; Wang, Ji; Wang, Miao; Li, Jin; Zhang, Chen; Nie, Kai; Yang, Mengjie; Zhang, Yi; Li, Aihua; Tan, Wenjie; Ma, Xuejun

2013-09-27

107

Development of a New Resequencing Pathogen Microarray Based Assay for Detection of Broad-Spectrum Respiratory Tract Viruses in Patients with Community-Acquired Pneumonia  

PubMed Central

A Resequencing Pathogen Microarray (RPM) is a single, highly multiplexed assay for detecting and differentiating similarly related pathogens by using closely overlapping probe sets to determine a target organism’s nucleotide sequence. In this study, a new RPM (RPM-IVDC1) that consisted of 224-bp detector tiles corresponding to 9 influenza A subtypes, 11 rhinoviruses, 28 enteroviruses and 38 other respiratory viruses was developed and optimized to provide individual and simultaneous detection sensitivities ranging from 15 to 750 genomic copies for 16 common respiratory pathogens. A total of 110 consecutive patients with community-acquired pneumonia (CAP) admitted to 5 district general hospitals in Beijing during a 1-year period were assessed using the new assay. Among the children (under age 5) and adult patients (above age 18), respiratory syncytial virus (RSV) and rhinovirus (RV) were the most common etiological agents, respectively, which is consistent with reference assays. Atypical pathogens that may cause CAP-like illness, including rubella virus, measles virus, influenza type C virus, human herpesvirus (HHV) were also detected. The results show the capability of RPM-IVDC1 for the accurate detection and identification of multiple virus types, which may be of significant use in epidemic surveillance and outbreak investigations of atypical pathogens.

Wang, Miao; Li, Jin; Zhang, Chen; Nie, Kai; Yang, Mengjie; Zhang, Yi; Li, Aihua; Tan, Wenjie; Ma, Xuejun

2013-01-01

108

Establishing a liquid-covered culture of polarized human airway epithelial Calu-3 cells to study host cell response to respiratory pathogens in vitro.  

PubMed

The apical and basolateral surfaces of airway epithelial cells demonstrate directional responses to pathogen exposure in vivo. Thus, ideal in vitro models for examining cellular responses to respiratory pathogens polarize, forming apical and basolateral surfaces. One such model is differentiated normal human bronchial epithelial cells (NHBE). However, this system requires lung tissue samples, expertise isolating and culturing epithelial cells from tissue, and time to generate an air-liquid interface culture. Calu-3 cells, derived from a human bronchial adenocarcinoma, are an alternative model for examining the response of proximal airway epithelial cells to respiratory insult, pharmacological compounds, and bacterial and viral pathogens, including influenza virus, rhinovirus and severe acute respiratory syndrome-associated coronavirus. Recently, we demonstrated that Calu-3 cells are susceptible to respiratory syncytial virus (RSV) infection in a manner consistent with NHBE. Here, we detail the establishment of a polarized, liquid-covered culture (LCC) of Calu-3 cells, focusing on the technical details of growing and culturing Calu-3 cells, maintaining cells that have been cultured into LCC, and we present the method for performing respiratory virus infection of polarized Calu-3 cells. To consistently obtain polarized Calu-3 LCC, Calu-3 cells must be carefully subcultured before culturing in Transwell inserts. Calu-3 monolayer cultures should remain below 90% confluence, should be subcultured fewer than 10 times from frozen stock, and should regularly be supplied with fresh medium. Once cultured in Transwells, Calu-3 LCC must be handled with care. Irregular media changes and mechanical or physical disruption of the cell layers or plates negatively impact polarization for several hours or days. Polarization is monitored by evaluating trans-epithelial electrical resistance (TEER) and is verified by evaluating the passive equilibration of sodium fluorescein between the apical and basolateral compartments . Once TEER plateaus at or above 1,000 ?×cm(2), Calu-3 LCC are ready to use to examine cellular responses to respiratory pathogens. PMID:23426201

Harcourt, Jennifer L; Haynes, Lia M

2013-02-07

109

National and Regional Assessment of Antimicrobial Resistance among Community-Acquired Respiratory Tract Pathogens Identified in a 2005-2006 U.S. Faropenem Surveillance Study?  

PubMed Central

Surveillance studies conducted in the United States over the last decade have revealed increasing resistance among community-acquired respiratory pathogens, especially Streptococcus pneumoniae, that may limit future options for empirical therapy. The objective of this study was to assess the scope and magnitude of the problem at the national and regional levels during the 2005-2006 respiratory season (the season when community-acquired respiratory pathogens are prevalent) in the United States. Also, since faropenem is an oral penem being developed for the treatment of community-acquired respiratory tract infections, another study objective was to provide baseline data to benchmark changes in the susceptibility of U.S. respiratory pathogens to the drug in the future. The in vitro activities of faropenem and other agents were determined against 1,543 S. pneumoniae isolates, 978 Haemophilus influenzae isolates, and 489 Moraxella catarrhalis isolates collected from 104 U.S. laboratories across six geographic regions during the 2005-2006 respiratory season. Among S. pneumoniae isolates, the rates of resistance to penicillin, amoxicillin-clavulanate, and cefdinir were 16, 6.4, and 19.2%, respectively. The least effective agents were trimethoprim-sulfamethoxazole (SXT) and azithromycin, with resistance rates of 23.5 and 34%, respectively. Penicillin resistance rates for S. pneumoniae varied by region (from 8.7 to 22.5%), as did multidrug resistance rates for S. pneumoniae (from 8.8 to 24.9%). Resistance to ?-lactams, azithromycin, and SXT was higher among S. pneumoniae isolates from children than those from adults. ?-Lactamase production rates among H. influenzae and M. catarrhalis isolates were 27.4 and 91.6%, respectively. Faropenem MICs at which 90% of isolates are inhibited were 0.5 ?g/ml for S. pneumoniae, 1 ?g/ml for H. influenzae, and 0.5 ?g/ml for M. catarrhalis, suggesting that faropenem shows promise as a treatment option for respiratory infections caused by contemporary resistant phenotypes.

Critchley, Ian A.; Brown, Steven D.; Traczewski, Maria M.; Tillotson, Glenn S.; Janjic, Nebojsa

2007-01-01

110

Nucleic acid-associated autoantigens: Pathogenic involvement and therapeutic potential  

Microsoft Academic Search

Autoimmunity to ubiquitously expressed macromolecular nucleic acid–protein complexes such as the nucleosome or the spliceosome is a characteristic feature of systemic autoimmune diseases. Disease-specificity and\\/or association with clinical features of some of these autoimmune responses suggest pathogenic involvement which, however, has been proven in only a few cases so far. Although the mechanisms leading to autoimmunity against nucleic acid-containing complexes

Markus H. Hoffmann; Sylvie Trembleau; Sylviane Muller; Günter Steiner

2010-01-01

111

The broadly conserved regulator PhoP links pathogen virulence and membrane potential in Escherichia coli  

PubMed Central

Summary PhoP is considered a virulence regulator despite being conserved in both pathogenic and non-pathogenic Enterobacteriaceae. While Escherichia coli strains represent non-pathogenic commensal isolates and numerous virulent pathotypes, the PhoP virulence regulator has only been studied in commensal E. coli. To better understand how conserved transcription factors contribute to virulence, we characterized PhoP in pathogenic E. coli. Deletion of phoP significantly attenuated E. coli during extraintestinal infection. This was not surprising since we demonstrated that PhoP differentially regulated the transcription of >600 genes. In addition to survival at acidic pH and resistance to polymyxin, PhoP was required for repression of motility and oxygen-independent changes in the expression of primary dehydrogenase and terminal reductase respiratory chain components. All phenotypes have in common a reliance on an energized membrane. Thus, we hypothesized that PhoP mediates these effects by regulating genes encoding proteins that generate proton motive force. Indeed, bacteria lacking PhoP exhibited a hyper-polarized membrane and dissipation of the transmembrane electrochemical gradient increased susceptibility of the phoP mutant to acidic pH, while inhibiting respiratory generation of the proton gradient restored resistance to antimicrobial peptides independent of lipopolysaccharide modification. These findings demonstrate a connection between PhoP, virulence, and the energized state of the membrane.

Alteri, Christopher J.; Lindner, Jonathon R.; Reiss, Daniel J.; Smith, Sara N.; Mobley, Harry L.T.

2011-01-01

112

Spectrum and potency of ceftaroline tested against leading pathogens causing community-acquired respiratory tract infections in Europe (2010).  

PubMed

Ceftaroline, the active metabolite of the prodrug ceftaroline fosamil, is a novel cephalosporin exhibiting in vitro bactericidal activity against Gram-positive organisms, including Streptococcus pneumoniae and methicillin-susceptible and -resistant Staphylococcus aureus, as well as common Gram-negative organisms. The objective of this study was to determine the spectrum and potency of ceftaroline against recent leading pathogens causing community-acquired respiratory tract infections (CARTI) isolated in Europe. A total of 1563 isolates from the 2010 Assessing Worldwide Antimicrobial Resistance Evaluation (AWARE) Program were identified as CARTI pathogens by the infection type and/or specimen type recorded by the participating laboratory. Isolates were collected from patients in 52 medical centers located in 19 European countries (including Israel and Turkey). Susceptibility testing for ceftaroline and commonly used antimicrobials was performed by Clinical and Laboratory Standards Institute (CLSI) broth microdilution methodology. Susceptibility interpretations for comparators were as published in CLSI and the European Committee on Antimicrobial Susceptibility Testing guidelines, and for ceftaroline US-FDA breakpoints were also applied. Ceftaroline was very active overall against 799 S. pneumoniae (MIC(50/90,) ? 0.008/0.12 ?g/mL) and inhibited 100.0% of all isolates at a MIC ? 0.5 ?g/mL. Ceftaroline was very potent against penicillin-resistant (CLSI oral penicillin V breakpoints) and -intermediate S. pneumoniae (MIC(50/90), 0.12/0.25 and 0.03/0.12 ?g/mL, respectively), but potency was lower than observed against penicillin-susceptible isolates (MIC(50/90), ? 0.008/? 0.008 ?g/mL). Ceftaroline was also very active (MIC(50/90), ? 0.008/0.015 ?g/mL) against 515 Haemophilus influenzae, including ?-lactamase-producing strains (MIC(50/90), 0.015/0.06 ?g/mL). Ceftaroline also demonstrated good activity against 205 Moraxella catarrhalis isolates (MIC(50/90), 0.06/0.12 ?g/mL). This study demonstrated the potent in vitro activity of ceftaroline against contemporary pathogens isolated from patients with documented CARTI from Europe. These data suggest that ceftaroline fosamil has an acceptable in vitro spectrum and potency against CARTI pathogens. PMID:23146404

Farrell, David J; Flamm, Robert K; Jones, Ronald N; Sader, Helio S

2012-11-10

113

Potential effects of global warming on oilseed rape pathogens in Northern Germany  

Microsoft Academic Search

This review analyses potential effects of global warming, i.e. higher mean temperatures, on the life cycle of five economically important oilseed rape pathogens in Northern Germany using a meta-analytical approach. First, the currently available but strongly fragmented knowledge about temperature influences on individual life cycle stages of the referred pathogens, such as survival, sporulation, infection and disease progress is summarised.

Magdalena Siebold; Andreas von Tiedemann

114

Rare occurrence of heterotrophic bacteria with pathogenic potential in potable water  

Microsoft Academic Search

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

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

2004-01-01

115

[Assessment of persistent potential dominant pathogens of acute intestinal infections].  

PubMed

To determine the prevalence,and etiological structure of acute intestinal infections, to investigate the dominant agents' persistence factors. According with materials of statistical reports we did the retrospective epidemiological analysis of acute intestinal infections incidence in Sumy region from 2006 till 2011. Biological properties of 40 strains of Klebsiella pneumonia, 40 strains of Enterobacter cloacae and 50 strains of Staphylococcus aureus were investigated. Moderate trend of acute intestinal infections incidence increase was indicated. Bacteria of genera Klebsiella, Enterobacter, Staphylococcus were predominated in etiological structure. Incidence of acute diarrheal infections caused by Klebsiella and Enterobacter was reached the maximum in the spring-summer period. The incidence of staphylococcal etiology was discrete. The strains of Klebsiella pneumonia, Staphylococcus aureus and Enterobacter cloacae were remarkable for different frequency and intensity of persistence factors. ?nti-interferon activity was detected in 100% of clinical isolates of microorganisms, anti-lysozym activity was detected in 87.3 ± 2.9% of clinical isolates of microorganisms, anti-complementary activity was detected in 72.3 ± 3.9% of clinical isolates of microorganisms. Biological properties of opportunistic pathogens that cause acute intestinal infections can be used as epidemiological factors for differentiation of microorganisms pathogenicity. PMID:23787508

2013-05-01

116

Polymicrobial respiratory disease in pigs.  

PubMed

Respiratory disease in pigs is common in modern pork production worldwide and is often referred to as porcine respiratory disease complex (PRDC). PRDC is polymicrobial in nature, and results from infection with various combinations of primary and secondary respiratory pathogens. As a true multifactorial disease, environmental conditions, population size, management strategies and pig-specific factors such as age and genetics also play critical roles in the outcome of PRDC. While non-infectious factors are important in the initiation and outcome of cases of PRDC, the focus of this review is on infectious factors only. There are a variety of viral and bacterial pathogens commonly associated with PRDC including porcine reproductive and respiratory syndrome virus (PRRSV), swine influenza virus (SIV), porcine circovirus type 2 (PCV2), Mycoplasma hyopneumoniae (MHYO) and Pasteurella multocida (PMULT). The pathogenesis of viral respiratory disease is typically associated with destruction of the mucocilliary apparatus and with interference and decrease of the function of pulmonary alveolar and intravascular macrophages. Bacterial pathogens often contribute to PRDC by activation of inflammation via enhanced cytokine responses. With recent advancements in pathogen detection methods, the importance of polymicrobial disease has become more evident, and identification of interactions of pathogens and their mechanisms of disease potentiation has become a topic of great interest. For example, combined infection of pigs with typically low pathogenic organisms like PCV2 and MHYO results in severe respiratory disease. Although the body of knowledge has advanced substantially in the last 15 years, much more needs to be learned about the pathogenesis and best practices for control of swine respiratory disease outbreaks caused by concurrent infection of two or more pathogens. This review discusses the latest findings on polymicrobial respiratory disease in pigs. PMID:22152290

Opriessnig, T; Giménez-Lirola, L G; Halbur, P G

2011-12-01

117

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

National Technical Information Service (NTIS)

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,...

A. Morales J. L. Garland D. V. Lim

1996-01-01

118

Effect of Treated Rum Distillery Effluents on the Distribution and Survival of Potential Bacterial Pathogens.  

National Technical Information Service (NTIS)

The study determines the efficiency of the methane anaerobic digestion treatment on rum distillery effluents and its capacity to change population of potentially pathogenic bacteria. It was concluded that methane anaerobic digestion treatment fails to sig...

T. C. Hazen G. Toranzos

1987-01-01

119

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...

120

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...

121

Concurrent highly pathogenic porcine reproductive and respiratory syndrome virus infection accelerates Haemophilus parasuis infection in conventional pigs.  

PubMed

This study was aimed at determining the effect of highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) on Haemophilus parasuis (HPS) in co-infection. A quantitative real-time PCR targeting infB gene, which is conserved among different HPS serotypes, was developed to improve the accuracy and speed of the detection of HPS. A total of 32 four-week-old conventional pigs were distributed randomly into four groups: pigs in group I were intranasally infected with HP-PRRSV first, and were then intraperitoneally inoculated with HPS on 5 days after HP-PRRSV infection; pigs in group II were intranasally inoculated with HP-PRRSV alone; pigs in group III were intraperitoneally inoculated with HPS alone; pigs in group IV were intraperitoneally inoculated with physiological saline. The amount of HPS in serum on 0, 3, 6, 9 and 12 days post-inoculation (dpi) with HPS were detected using the established quantitative real-time PCR. Clinical signs, pathological changes and histopathological lesions were observed. The amount of HPS in serum reached 10(6)copies/?l at 3 dpi with HPS in pigs of group I, while it arrived 10(5.7)copies/?l at 9 dpi with HPS in pigs of group III. The HPS loads in hearts and lungs were much higher than in other tissues. The study showed that HP-PRRSV was able to accelerate HPS infection and loads. PMID:22460022

Yu, Jiang; Wu, Jiaqiang; Zhang, Yuyu; Guo, Lihui; Cong, Xiaoyan; Du, Yijun; Li, Jun; Sun, Wenbo; Shi, Jianli; Peng, Jun; Yin, Feifei; Wang, Dapeng; Zhao, Pengwei; Wang, Jinbao

2012-03-08

122

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

PubMed

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. PMID:20217405

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

2010-03-09

123

Potential mechanisms underlying the acute lung dysfunction and bacterial extrapulmonary dissemination during Burkholderia cenocepacia respiratory infection  

PubMed Central

Background Burkholderia cenocepacia, an opportunistic pathogen that causes lung infections in cystic fibrosis (CF) patients, is associated with rapid and usually fatal lung deterioration due to necrotizing pneumonia and sepsis, a condition known as cepacia syndrome. The key bacterial determinants associated with this poor clinical outcome in CF patients are not clear. In this study, the cytotoxicity and procoagulant activity of B. cenocepacia from the ET-12 lineage, that has been linked to the cepacia syndrome, and four clinical isolates recovered from CF patients with mild clinical courses were analysed in both in vitro and in vivo assays. Methods B. cenocepacia-infected BEAS-2B epithelial respiratory cells were used to investigate the bacterial cytotoxicity assessed by the flow cytometric detection of cell staining with propidium iodide. Bacteria-induced procoagulant activity in cell cultures was assessed by a colorimetric assay and by the flow cytometric detection of tissue factor (TF)-bearing microparticles in cell culture supernatants. Bronchoalveolar lavage fluids (BALF) from intratracheally infected mice were assessed for bacterial proinflammatory and procoagulant activities as well as for bacterial cytotoxicity, by the detection of released lactate dehydrogenase. Results ET-12 was significantly more cytotoxic to cell cultures but clinical isolates Cl-2, Cl-3 and Cl-4 exhibited also a cytotoxic profile. ET-12 and CI-2 were similarly able to generate a TF-dependent procoagulant environment in cell culture supernatant and to enhance the release of TF-bearing microparticles from infected cells. In the in vivo assay, all bacterial isolates disseminated from the mice lungs, but Cl-2 and Cl-4 exhibited the highest rates of recovery from mice livers. Interestingly, Cl-2 and Cl-4, together with ET-12, exhibited the highest cytotoxicity. All bacteria were similarly capable of generating a procoagulant and inflammatory environment in animal lungs. Conclusion B. cenocepacia were shown to exhibit cytotoxic and procoagulant activities potentially implicated in bacterial dissemination into the circulation and acute pulmonary decline detected in susceptible CF patients. Improved understanding of the mechanisms accounting for B. cenocepacia-induced clinical decline has the potential to indicate novel therapeutic strategies to be included in the care B. cenocepacia-infected patients.

2010-01-01

124

Bioengineered 2'-fucosyllactose and 3-fucosyllactose inhibit the adhesion of Pseudomonas aeruginosa and enteric pathogens to human intestinal and respiratory cell lines.  

PubMed

Human milk oligosaccharides help to prevent infectious diseases in breastfed infants. Larger scale testing, particularly in animal models and human clinical studies, is still limited due to shortened availability of more complex oligosaccharides. The purpose of this study was to evaluate 2'-fucosyllactose (2'-FL) and 3-fucosyllactose (3-FL) synthesized by whole-cell biocatalysis for their biological activity in vitro. Therefore, we have tested these oligosaccharides for their inhibitory potential of pathogen adhesion in two different human epithelial cell lines. 2'-FL could inhibit adhesion of Campylobacter jejuni, enteropathogenic Escherichia coli, Salmonella enterica serovar fyris, and Pseudomonas aeruginosa to the intestinal human cell line Caco-2 (reduction of 26%, 18%, 12%, and 17%, respectively), as could be shown for 3-FL (enteropathogenic E coli 29%, P aeruginosa 26%). Furthermore, adherence of P aeruginosa to the human respiratory epithelial cell line A549 was significantly inhibited by 2'-FL and 3-FL (reduction of 24% and 23%, respectively). These results confirm the biological and functional activity of biotechnologically synthesized human milk oligosaccharides. Mass-tailored human milk oligosaccharides could be used in the future to supplement infant formula ingredients or as preventatives to reduce the impact of infectious diseases. PMID:24074741

Weichert, Stefan; Jennewein, Stefan; Hüfner, Eric; Weiss, Christel; Borkowski, Julia; Putze, Johannes; Schroten, Horst

2013-08-13

125

Potential use of microarray technology for rapid identification of central nervous system pathogens.  

PubMed

Outbreaks of central nervous system (CNS) diseases result in significant productivity and financial losses, threatening peace and wartime readiness capabilities. To meet this threat, rapid clinical diagnostic tools for detecting and identifying CNS pathogens are needed. Current tools and techniques cannot efficiently deal with CNS pathogen diversity; they cannot provide real-time identification of pathogen serogroups and strains, and they require days, sometimes weeks, for examination of tissue culture. Rapid and precise CNS pathogen diagnostics are needed to provide the opportunity for tailored therapeutic regimens and focused preventive efforts to decrease morbidity and mortality. Such diagnostics are available through genetic and genomic technologies, which have the potential for reducing the time required in serogroup or strain identification from 500+ hours for some viral cultures to less than 3 hours for all pathogens. In the near future, microarray diagnostics and future derivations of these technologies will change the paradigm used for outbreak investigations and will improve health care for all. PMID:15379069

Hanson, Eric H; Niemeyer, Debra M; Folio, Les; Agan, Brian K; Rowley, Robb K

2004-08-01

126

PROTEKT 1999–2000: a multicentre study of the antibiotic susceptibility of respiratory tract pathogens in Hong Kong, Japan and South Korea  

Microsoft Academic Search

A multicentre surveillance study performed in the Far East during 1999–2000 investigated the in vitro activity of >20 antibacterials against common respiratory pathogens. In Hong Kong, Japan, and South Korea, 57.1, 44.5 and 71.5% Streptococcus pneumoniae were penicillin-resistant and 71.4, 77.9 and 87.6% were erythromycin-resistant, respectively. Overall, >90% of penicillin-resistant strains were also macrolide-resistant. All strains were susceptible to telithromycin.

Matsuhisa Inoue; Nam Yong Lee; Seto Wing Hong; Kyungwon Lee; David Felmingham

2004-01-01

127

During the summer 2009 outbreak of "swine flu" in Scotland what respiratory pathogens were diagnosed as H1N1/2009?  

PubMed Central

Background During the April-July 2009 outbreak of H1N1/2009 in scotland the West of Scotland Specialist Virology Centre (WoSSVC) in Glasgow tested > 16 000 clinical samples for H1N1/2009. Most were from patients clinically diagnosed with H1N1/2009. Out of these, 9% were positive. This study sought to determine what respiratory pathogens were misdiagnosed as cases of H1N1/2009 during this time. Methods We examined the results from 3247 samples which were sent to the laboratory during April-July 2009. All were from patients clinically diagnosed as having H1N1/2009 (based on accepted criteria) and all were given a full respiratory screen using real time reverse transcriptase polymerase chain reaction (rtRT-PCR) assays. Results In total, respiratory pathogens were detected in 27.9% (95% confidence interval, 26.3-29.5%) of the samples submitted. Numerous pathogens were detected, the most common of which were rhinovirus (8.9% (95% confidence interval, 7.9-9.9%)), parainfluenza 1 (1.9% (95% confidence interval, 1.4-2.4%)) and 3 (4.1% (95% confidence interval, 3.3-4.9%)), and adenovirus ((3.5% (95% confidence interval, 2.9-4.2%)). Conclusions This study highlights the problems of using a clinical algorithm to detect H1N1/2009. Clinicians frequently misdiagnosed common respiratory pathogens as H1N1/2009 during the spring/summer outbreak in Scotland. Many undesirable consequences would have resulted, relating to treatment, infection control, and public health surveillance.

2011-01-01

128

In vitro microbiological characterization of a novel azalide, two triamilides and an azalide ketal against bovine and porcine respiratory pathogens.  

PubMed

Several novel 15-membered-ring macrolide agents (azalide 1, triamilides 2 and 3, and the azalide 3,6-ketal 4) were identified as potential antibacterial agents against Mannheimia (formerly named as Pasteurella) haemolytica, Pasteurella multocida, Haemophilus somnus and Actinobacillus pleuropneumoniae, important etiological agents of bovine and porcine respiratory disease. Compound 3 is the major component of the antibiotic tulathromycin. Antibacterial activity against tilmicosin-resistant P. multocida field isolates was also tested. In vitro MIC 50/90 analysis revealed that the four newly synthesized compounds were more potent than tilmicosin against M. haemolytica (4 to approximately 8x), P. multocida (8 to approximately 16x), A. pleuropneumoniae (4x), H. somnus (2x and 16x), and tilmicosin-resistant P. multocida (32x). In time-kill kinetic studies, all four novel compounds and tilmicosin showed bactericidal activity against M. haemolytica, P. multocida and A. pleuropneumoniae at both 4x and 8x MIC. A functional assay using genetically defined mutants revealed that all four novel compounds were poorer substrates for the efflux pump, AcrA/B system, than tilmicosin. A pH study using LPS mutants indicated that the enhanced in vitro potency of the triamilides, particularly compound 3 was mainly due to better penetration of the molecule through the outer membrane. The third amine group at the C-4'' position of the triamilde molecules contributed to this increased membrane penetration by increasing overall basicity. These studies indicate that the four novel compounds have potential as antibacterial agents against bovine and porcine respiratory disease. PMID:15217193

Norcia, Laura J L; Silvia, Annette M; Santoro, Sheryl L; Retsema, Jim; Letavic, Michael A; Bronk, Brian S; Lundy, Kristin M; Yang, Bingwei; Evans, Nigel A; Hayashi, Shigeru F

2004-04-01

129

The Caenorhabditis elegans assay: a tool to evaluate the pathogenic potential of bacterial biocontrol agents  

Microsoft Academic Search

Bacterial biocontrol agents (BCAs) open up the possibility of controlling plant pathogens in an environmentally friendly way.\\u000a Although they are naturally occurring microbes, some of them can cause diseases in humans. For successful registration it\\u000a is necessary to test potentially adverse effects on the human health of at-risk candidates. Existing pathogenicity assays\\u000a are cost-intensive, time-consuming and furthermore they are often

Christin Zachow; Heidemarie Pirker; Christian Westendorf; Ralf Tilcher; Gabriele Berg

2009-01-01

130

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

PubMed

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)-? 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. PMID:23313323

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

2012-11-29

131

National and regional assessment of antimicrobial resistance among community-acquired respiratory tract pathogens identified in a 2005-2006 U.S. Faropenem surveillance study.  

PubMed

Surveillance studies conducted in the United States over the last decade have revealed increasing resistance among community-acquired respiratory pathogens, especially Streptococcus pneumoniae, that may limit future options for empirical therapy. The objective of this study was to assess the scope and magnitude of the problem at the national and regional levels during the 2005-2006 respiratory season (the season when community-acquired respiratory pathogens are prevalent) in the United States. Also, since faropenem is an oral penem being developed for the treatment of community-acquired respiratory tract infections, another study objective was to provide baseline data to benchmark changes in the susceptibility of U.S. respiratory pathogens to the drug in the future. The in vitro activities of faropenem and other agents were determined against 1,543 S. pneumoniae isolates, 978 Haemophilus influenzae isolates, and 489 Moraxella catarrhalis isolates collected from 104 U.S. laboratories across six geographic regions during the 2005-2006 respiratory season. Among S. pneumoniae isolates, the rates of resistance to penicillin, amoxicillin-clavulanate, and cefdinir were 16, 6.4, and 19.2%, respectively. The least effective agents were trimethoprim-sulfamethoxazole (SXT) and azithromycin, with resistance rates of 23.5 and 34%, respectively. Penicillin resistance rates for S. pneumoniae varied by region (from 8.7 to 22.5%), as did multidrug resistance rates for S. pneumoniae (from 8.8 to 24.9%). Resistance to beta-lactams, azithromycin, and SXT was higher among S. pneumoniae isolates from children than those from adults. beta-Lactamase production rates among H. influenzae and M. catarrhalis isolates were 27.4 and 91.6%, respectively. Faropenem MICs at which 90% of isolates are inhibited were 0.5 mug/ml for S. pneumoniae, 1 mug/ml for H. influenzae, and 0.5 mug/ml for M. catarrhalis, suggesting that faropenem shows promise as a treatment option for respiratory infections caused by contemporary resistant phenotypes. PMID:17908940

Critchley, Ian A; Brown, Steven D; Traczewski, Maria M; Tillotson, Glenn S; Janjic, Nebojsa

2007-10-01

132

Pathogenic potential of adipose tissue and metabolic consequences of adipocyte hypertrophy and increased visceral adiposity.  

PubMed

When caloric intake exceeds caloric expenditure, the positive caloric balance and storage of energy in adipose tissue often causes adipocyte hypertrophy and visceral adipose tissue accumulation. These pathogenic anatomic abnormalities may incite metabolic and immune responses that promote Type 2 diabetes mellitus, hypertension and dyslipidemia. These are the most common metabolic diseases managed by clinicians and are all major cardiovascular disease risk factors. 'Disease' is traditionally characterized as anatomic and physiologic abnormalities of an organ or organ system that contributes to adverse health consequences. Using this definition, pathogenic adipose tissue is no less a disease than diseases of other body organs. This review describes the consequences of pathogenic fat cell hypertrophy and visceral adiposity, emphasizing the mechanistic contributions of genetic and environmental predispositions, adipogenesis, fat storage, free fatty acid metabolism, adipocyte factors and inflammation. Appreciating the full pathogenic potential of adipose tissue requires an integrated perspective, recognizing the importance of 'cross-talk' and interactions between adipose tissue and other body systems. Thus, the adverse metabolic consequences that accompany fat cell hypertrophy and visceral adiposity are best viewed as a pathologic partnership between the pathogenic potential adipose tissue and the inherited or acquired limitations and/or impairments of other body organs. A better understanding of the physiological and pathological interplay of pathogenic adipose tissue with other organs and organ systems may assist in developing better strategies in treating metabolic disease and reducing cardiovascular disease risk. PMID:18327995

Bays, Harold E; González-Campoy, J Michael; Bray, George A; Kitabchi, Abbas E; Bergman, Donald A; Schorr, Alan Bruce; Rodbard, Helena W; Henry, Robert R

2008-03-01

133

Evaluating the Pathogenic Potential of Environmental Escherichia coli by Using the Caenorhabditis elegans Infection Model  

PubMed Central

The detection and abundance of Escherichia coli in water is used to monitor and mandate the quality of drinking and recreational water. Distinguishing commensal waterborne E. coli isolates from those that cause diarrhea or extraintestinal disease in humans is important for quantifying human health risk. A DNA microarray was used to evaluate the distribution of virulence genes in 148 E. coli environmental isolates from a watershed in eastern Ontario, Canada, and in eight clinical isolates. Their pathogenic potential was evaluated with Caenorhabditis elegans, and the concordance between the bioassay result and the pathotype deduced by genotyping was explored. Isolates identified as potentially pathogenic on the basis of their complement of virulence genes were significantly more likely to be pathogenic to C. elegans than those determined to be potentially nonpathogenic. A number of isolates that were identified as nonpathogenic on the basis of genotyping were pathogenic in the infection assay, suggesting that genotyping did not capture all potentially pathogenic types. The detection of the adhesin-encoding genes sfaD, focA, and focG, which encode adhesins; of iroN2, which encodes a siderophore receptor; of pic, which encodes an autotransporter protein; and of b1432, which encodes a putative transposase, was significantly associated with pathogenicity in the infection assay. Overall, E. coli isolates predicted to be pathogenic on the basis of genotyping were indeed so in the C. elegans infection assay. Furthermore, the detection of C. elegans-infective environmental isolates predicted to be nonpathogenic on the basis of genotyping suggests that there are hitherto-unrecognized virulence factors or combinations thereof that are important in the establishment of infection.

Merkx-Jacques, Alexandra; Coors, Anja; Brousseau, Roland; Masson, Luke; Mazza, Alberto; Tien, Yuan-Ching

2013-01-01

134

Evaluating the pathogenic potential of environmental Escherichia coli by using the Caenorhabditis elegans infection model.  

PubMed

The detection and abundance of Escherichia coli in water is used to monitor and mandate the quality of drinking and recreational water. Distinguishing commensal waterborne E. coli isolates from those that cause diarrhea or extraintestinal disease in humans is important for quantifying human health risk. A DNA microarray was used to evaluate the distribution of virulence genes in 148 E. coli environmental isolates from a watershed in eastern Ontario, Canada, and in eight clinical isolates. Their pathogenic potential was evaluated with Caenorhabditis elegans, and the concordance between the bioassay result and the pathotype deduced by genotyping was explored. Isolates identified as potentially pathogenic on the basis of their complement of virulence genes were significantly more likely to be pathogenic to C. elegans than those determined to be potentially nonpathogenic. A number of isolates that were identified as nonpathogenic on the basis of genotyping were pathogenic in the infection assay, suggesting that genotyping did not capture all potentially pathogenic types. The detection of the adhesin-encoding genes sfaD, focA, and focG, which encode adhesins; of iroN2, which encodes a siderophore receptor; of pic, which encodes an autotransporter protein; and of b1432, which encodes a putative transposase, was significantly associated with pathogenicity in the infection assay. Overall, E. coli isolates predicted to be pathogenic on the basis of genotyping were indeed so in the C. elegans infection assay. Furthermore, the detection of C. elegans-infective environmental isolates predicted to be nonpathogenic on the basis of genotyping suggests that there are hitherto-unrecognized virulence factors or combinations thereof that are important in the establishment of infection. PMID:23377948

Merkx-Jacques, Alexandra; Coors, Anja; Brousseau, Roland; Masson, Luke; Mazza, Alberto; Tien, Yuan-Ching; Topp, Edward

2013-02-01

135

Hepatitis B Precore Protein: Pathogenic Potential and Therapeutic Promise  

PubMed Central

Hepatitis B virus (HBV), a small and economically packaged double-stranded DNA virus, represents an enormous global health care burden. In spite of an effective vaccine, HBV is endemic in many countries. Chronic hepatitis B (CHB) results in the development of significant clinical outcomes such as liver disease and hepatocellular carcinoma (HCC), which are associated with high mortality rates. HBV is a non-cytopathic virus, with the host's immune response responsible for the associated liver damage. Indeed, HBV appears to be a master of manipulating and modulating the immune response to achieve persistent and chronic infection. The HBV precore protein or hepatitis B e antigen (HBeAg) is a key viral protein involved in these processes, for instance though the down-regulation of the innate immune response. The development of new therapies that target viral proteins, such as HBeAg, which regulates of the immune system, may offer a new wave of potential therapeutics to circumvent progression to CHB and liver disease.

Locarnini, Stephen

2012-01-01

136

Comparison of in vivo and in vitro methods for pathogenicity evaluation for mycoplasma gallisepticum in respiratory infection  

Microsoft Academic Search

This study was designated to examine the pathogenicity of several strains of Mycoplasma gallisepticum (R, F, S?6, 227 and A5969) and laboratory derived substrains. Preliminary results indicated that the nine M. gallisepticum strains differed markedly in their pathogenicity for chickens. A comparison was made between various in vivo and in vitro methods for quantitative evaluation of pathogenicity. Reproducibility, convenience, and

Sharon Levisohn; M. J. Dykstra; M. Y. Lin; S. H. Kleven

1986-01-01

137

Membrane potentials of respiratory neurones during dizocilpine-induced apneusis in adult cats.  

PubMed

1. In the vagotomized cat, blockade of NMDA receptors by dizocilpine (MK-801) produces an apneustic pattern of respiration characterized by a large increase in the duration of inspiration. 2. To identify dizocilpine-induced disfacilitations and disinhibitions in respiratory neurones generating the respiratory rhythm, membrane potential and input resistance of augmenting inspiratory (I; n = 11) and post-inspiratory (PI; n = 9) neurones were examined in the ventral respiratory group area, before and after administration of dizocilpine (0.1-0.3 mg kg-1 i.v.) in decerebrate, vagotomized, paralysed and artificially ventilated cats. 3. In I neurones, dizocilpine decreased the ramp depolarization and an 82% increase in input resistance was observed during inspiration. The inspiratory phase was prolonged, leading to a sustained level of depolarization during apneusis. The amplitude of stage 1 expiratory hyperpolarization decreased and its decay, which is normally slow, was faster. Throughout the remainder of expiration (stage 2) the membrane potential levelled off and the input resistance increased slightly (by 15%). 4. In PI neurones, dizocilpine depressed depolarization and suppressed firing in eight out of nine cells during the stage 1 expiratory phase. This was associated with a large (91%) increase of input resistance. The membrane potential switched quickly to stage 2 expiratory repolarization, during which a slight (19%) increase in input resistance occurred. 5. The hyperpolarization of PI neurones during early inspiration was reduced in amplitude by dizocilpine and input resistance was increased by 75% during inspiration, indicating that dizocilpine reduced the activity of the presynaptic inhibitory early-inspiratory (eI) neurones. 6. We conclude that NMDA receptor blockade in the respiratory network disfacilitates eI, I and PI neurones during their active phase. Decreased inhibitory processes during the inspiratory phase probably play a major role in the prolongation of inspiration. PMID:8887787

Haji, A; Pierrefiche, O; Takeda, R; Foutz, A S; Champagnat, J; Denavit-Saubié, M

1996-09-15

138

Effects of upper airway anaesthesia on respiratory-related evoked potentials in humans.  

PubMed

Cortical potentials evoked by mid-inspiratory occlusion arise from numerous receptors, many of which are probably within the upper airway. Their precise nature is not known. The aim of the current study was to improve knowledge of this by studying the effects of topical upper airway anaesthesia on respiratory-related evoked potentials. Respiratory-related evoked potentials were described through the averaging of electroencephalogram (EEG) epochs following mid-inspiratory occlusions (C3-CZ; C4-CZ). A total of 21 healthy volunteers (13 male, aged 22-52 yrs) were studied during mouth breathing, before and after topical upper airway anaesthesia (lidocaine). Moreover, 15 subjects were studied during nose breathing with and without anaesthesia. Six subjects were studied whilst inhaling L-menthol. Typical potentials were present in all the subjects, their components featuring normal amplitudes and latencies. The route of breathing and upper airway anaesthesia did not modify the EEG responses to inspiratory occlusions, qualitatively or quantitatively, during mouth or nose breathing. L-menthol had no effect. Upper airway receptors sensitive to topical anaesthesia are unlikely to contribute significantly to mid-inspiratory occlusion-evoked potentials. On the contrary, deeper receptors, such as joint and muscle receptors, could contribute dominantly to these potentials. PMID:16319342

Redolfi, S; Raux, M; Donzel-Raynaud, C; Morelot-Panzini, C; Zelter, M; Derenne, J-P; Similowski, T; Straus, C

2005-12-01

139

Changing trend of antimicrobial resistance among pathogens isolated from lower respiratory tract at a university-affiliated hospital of China, 2006-2010  

PubMed Central

Objective To investigate the distribution and the antimicrobial resistance of pathogens in lower respiratory tract infection from 2006 to 2010. Methods The sputum specimens from inpatients with lower respiratory tract infection in the First Affiliated Hospital of Nanjing Medical University during the past five years were cultured and identified; the antimicrobial resistance was analyzed by the software WHONET 5.4. Results A total of 12,191 isolates were characterized in sputum samples: 73.5% were Gram-negative bacteria, 13.7% were Gram-positive bacteria, and 12.8% were fungi. The isolation rate of Acinetobacter was significantly increasing from 12.8% in 2006 to 26.4% in 2010. The Gram-negative bacterial resistance rate to the second and third generation cephalosporin increased year by year. Decreasing trend, 78.7% in 2006 decreased to 63.5% in 2010 (R2=0.93 and P<0.01), in resistance to clindamycin against Staphylococcus aureus was observed. Worth noting is the drug resistance of Acinetobacter and Klebsiella pneumoniae to carbapenem significantly increased (R2>0.3 and P?0.05). Conclusions The antimicrobial resistance of pathogens in lower respiratory tract infection increased in recent years. The hospitals and government departments should strengthen management of the use of some antibiotics, such as the second/third generation cephalosporin and carbapenem, in order to enhance the effectiveness of medication.

Xia, Wenying; Chen, Yi; Mei, Yaning; Wang, Tong; Liu, Genyan

2012-01-01

140

Potential pathogens and effective disinfectants on public telephones at a large urban United States university.  

PubMed

Telephones can carry potential bacterial pathogens, posing a risk for transfer of pathogens to users' hands. This study examined 25 mouthpieces of public telephones at a large urban U.S. university located in an area of rising incidence of community-acquired staphylococcal infections. Coagaulase-negative staphylococci were most commonly isolated (64% of mouthpieces). Potential pathogens isolated included Staphylococcus aureus, vancomycin-susceptible Enterococcus, and Klebsiella ozaenae. The efficacy of disinfectants on reducing bacterial counts on telephone mouthpieces was also investigated. Staphyloccocus aurens, Pseudomonas aeruginosa, and Enterococcusfaecalis were inoculated onto mouthpieces and challenged with disinfectant wipes. Bacterial counts were reduced substantially for all three organisms by wipes containing either 70% isopropyl alcohol, 1.84% sodium hypochlorite, or quaternary ammonium compounds. The sodium hypochlorite-based cleaner demonstrated 100% efficacy at removing or killing test organisms from telephone mouthpieces. These data suggest that tested cleaners may be appropriate and needed for public telephone disinfection. PMID:19192741

Annand, John W; Bajaj, Nikesh; Sheth, Anand; Burgess, Jaqqwon; Brooke, Joanna S

141

Comparison of extraintestinal pathogenic Escherichia coli strains from human and avian sources reveals a mixed subset representing potential zoonotic pathogens.  

PubMed

Since extraintestinal pathogenic Escherichia coli (ExPEC) strains from human and avian hosts encounter similar challenges in establishing infection in extraintestinal locations, they may share similar contents of virulence genes and capacities to cause disease. In the present study, 1,074 ExPEC isolates were classified by phylogenetic group and possession of 67 other traits, including virulence-associated genes and plasmid replicon types. These ExPEC isolates included 452 avian pathogenic E. coli strains from avian colibacillosis, 91 neonatal meningitis E. coli (NMEC) strains causing human neonatal meningitis, and 531 uropathogenic E. coli strains from human urinary tract infections. Cluster analysis of the data revealed that most members of each subpathotype represent a genetically distinct group and have distinguishing characteristics. However, a genotyping cluster containing 108 ExPEC isolates was identified, heavily mixed with regard to subpathotype, in which there was substantial trait overlap. Many of the isolates within this cluster belonged to the O1, O2, or O18 serogroup. Also, 58% belonged to the ST95 multilocus sequence typing group, and over 90% of them were assigned to the B2 phylogenetic group typical of human ExPEC strains. This cluster contained strains with a high number of both chromosome- and plasmid-associated ExPEC genes. Further characterization of this ExPEC subset with zoonotic potential urges future studies exploring the potential for the transmission of certain ExPEC strains between humans and animals. Also, the widespread occurrence of plasmids among NMEC strains and members of the mixed cluster suggests that plasmid-mediated virulence in these pathotypes warrants further attention. PMID:18820066

Johnson, Timothy J; Wannemuehler, Yvonne; Johnson, Sara J; Stell, Adam L; Doetkott, Curt; Johnson, James R; Kim, Kwang S; Spanjaard, Lodewijk; Nolan, Lisa K

2008-09-26

142

Sensitivity of Escherichia albertii, a potential foodborne pathogen, to food preservation treatments  

Technology Transfer Automated Retrieval System (TEKTRAN)

Escherichia albertii is a potential foodborne pathogen because of its documented ability to cause diarrheal disease by producing attachment and effacement lesions. Its tolerance to food preservation treatments has not been investigated. Heat, acid, and pressure tolerance were determined for stationa...

143

Microbial studies of compost: bacterial identification, and their potential for turfgrass pathogen suppression  

Microsoft Academic Search

Summary Composting is the degradation of organic materials through the activities of diverse microorganisms. This research examined microbial community dynamics, population levels and identification of bacteria throughout the composting process and in storage. In addition, an evaluation was performed to determine the potential for dominant bacterial isolates to suppress selected turfgrass pathogens: Sclerotinia homoeocarpa, Pythium graminicola, Typhula ishikariensis, and Microdochium

Jeanine I. Boulter; Jack T. Trevors; Greg J. Boland

2002-01-01

144

Microbial studies of compost: bacterial identification, and their potential for turfgrass pathogen suppression  

Microsoft Academic Search

Composting is the degradation of organic materials through the activities of diverse microorganisms. This research examined microbial community dynamics, population levels and identification of bacteria throughout the composting process and in storage. In addition, an evaluation was performed to determine the potential for dominant bacterial isolates to suppress selected turfgrass pathogens: Sclerotinia homoeocarpa, Pythium graminicola, Typhula ishikariensis, and Microdochium nivale,

Jeanine I. Boulter; Jack T. Trevors; Greg J. Boland

2002-01-01

145

Pathogens in livestock waste, their potential for movement through soil and environmental pollution  

Microsoft Academic Search

Livestock wastes contain many pathogenic microorganisms including bacteria, viruses and protozoa. Following the application of these wastes to land the potential exists for environmental contamination. Plants, soil and ultimately water courses which may subsequently be used as catchments for public water supplies may all be affected. Research attention is now being focused on this possibility, especially in the case of

Jane L. Mawdsley; Richard D. Bardgett; Roger J. Merry; Brian F. Pain; Michael K. Theodorou

1995-01-01

146

Methods to determine antipathogenic potential of phenolic and flavonoid compounds against urinary pathogen Serratia marcescens.  

PubMed

This study revealed the antipathogenic potential of natural compounds present in the edible fruits against urinary pathogen Serratia marcescens by using quorum sensing inhibition (QSI). The serum resistance assay was adopted to examine the immunomodulatory effects of QSI compounds to fight against bacterial infections. PMID:22759832

Annapoorani, Angusamy; Parameswari, Radhakrishnan; Pandian, Shunmugiah Karutha; Ravi, Arumugam Veera

2012-06-30

147

Correlation of gross tumor volume excursion with potential benefits of respiratory gating  

SciTech Connect

Purpose: To test the hypothesis that the magnitude of thoracic tumor motion can be used to determine the desirability of respiratory gating. Methods and materials: Twenty patients to be treated for lung tumors had computed tomography image data sets acquired under assisted breath hold at normal inspiration (100% tidal volume), at full expiration (0% tidal volume), and under free breathing. A radiation oncologist outlined gross tumor volumes (GTVs) on the breath-hold computed tomographic images. These data sets were registered to the free-breathing image data set. Two sets of treatment plans were generated: one based on an internal target volume explicitly formed from assessment of the excursion of the clinical target volume (CTV) through the respiratory cycle, representing an ungated treatment, and the other based on the 0% tidal volume CTV, representing a gated treatment with little margin for residual motion. Dose-volume statistics were correlated to the magnitude of the motion of the center of the GTV during respiration. Results: Patients whose GTVs were >100 cm{sup 3} showed little decrease in lung dose under gating. The other patients showed a correlation between the excursion of the center of the GTV and a reduction in potential lung toxicity. As residual motion increased, the benefits of respiratory gating increased. Conclusion: Gating seems to be advantageous for patients whose GTVs are <100 cm{sup 3} and for whom the center of the GTV exhibits significant motion, provided residual motion under gating is kept small.

Starkschall, George [Department of Radiation Physics, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States)]. E-mail: gstarksc@mdanderson.org; Forster, Kenneth M. [Department of Radiation Physics, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Kitamura, Kei [Department of Radiation Physics, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Department of Radiology, Hokkaido University, Graduate School of Medicine, Sapporo (Japan); Cardenas, Alex [Department of Radiation Physics, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Tucker, Susan L. [Department of Biomathematics, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Stevens, Craig W. [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States)

2004-11-15

148

The role of microbicidal lipids in host defense against pathogens and their potential as therapeutic agents.  

PubMed

Lipids such as fatty alcohols, free fatty acids and monoglycerides of fatty acids are known to be potent antimicrobial/microbicidal agents in vitro and to kill enveloped viruses, Gram-positive and Gram-negative bacteria and fungi on contact. For over half a century several studies have tried to answer the question of whether or not lipids play a role in the natural host defense against pathogens. A comprehensive review is given of these studies, particularly concerning infections in skin and in mucosal membranes of the respiratory tract, and of the role of lipids in the antimicrobial activity of breast milk. Based on studies of the microbicidal activities of lipids, both in vitro and in vivo, the possibility of using such lipids as active ingredients in prophylactic and therapeutic dosage forms is considered and examples are given of studies of such pharmaceutical dosage forms in experimental animal models and in clinical trials. PMID:17686469

Thormar, Halldor; Hilmarsson, Hilmar

2007-06-29

149

Assessing potential pathogenicity of avian influenza virus: current and experimental system.  

PubMed

An avian influenza (AI) isolate can be classified as a high pathogenicity avian influenza (HPAI) virus based upon the results of the standard intravenous pathogenicity index test; molecular classification, which is derived by sequencing the hemagglutinin gene across the site coding for the cleavage site; or a combination. However, discordant results between the molecular classification and virulence for experimentally infected chickens have been observed with several H5 and H7 subtype AI viruses. Because the declaration of HPAI virus results in severe effects on trade for the entire country, the gap between the genetic and phenotypic markers is an important issue, and it requires us to reexamine what should be considered an HPAI virus by the Office International des Epizooties standards. To better understand and assess the true virulence of the virus, potential pathogenicity of H5 and H7 subtype AI virus isolates has been assessed by examining the plaquing efficiency of the virus in chicken embryo fibroblast cells, conducting 14-day-old embryo passage and selection system, and applying in vitro mutagenesis coupled with reverse genetics. The potential value of these complimentary methods in assessing potential pathogenicity of the AI virus is discussed. PMID:17494562

Lee, C W; Lee, Y J; Swayne, D; Senne, D; Linares, D J; Suarez, D

2007-03-01

150

Genetic variability and pathogenicity potential of Escherichia coli isolated from recreational water reservoirs.  

PubMed

Contamination of recreational waters and public water supplies by Escherichia coli represents a risk for public health, since some strains can be pathogenic or propagated with other pathogenic microorganisms. In this study, two reservoirs, Billings and Guarapiranga (São Paulo metropolitan area, Brazil), were investigated in order to assess E. coli diversity. Genetic typing using rep-PCR completely differentiated all strains and enabled the determination of their genetic variability. Although the same level of genetic variability was observed for strains originating from both reservoirs, randomization procedures showed that isolates from the same reservoir were more closely related to each other. Phylogenetic group frequencies in each reservoir suggested that contamination in the Billings reservoir was mostly from humans, whereas contamination in the Guarapiranga reservoir was mostly from animals. Colony blot experiments using probes from several virulence factor genes showed that both reservoirs contained potential pathogenic strains and may represent a risk to recreational or household usage of these water resources. PMID:17467958

Orsi, Renato H; Stoppe, Nancy C; Sato, Maria Inês Z; Gomes, Tânia A T; Prado, Paulo I; Manfio, Gilson P; Ottoboni, Laura M M

2007-03-15

151

Potential benefits and pitfalls of respiratory-gated radiotherapy in the treatment of thoracic malignancy.  

PubMed

AIM: Despite advances in radiotherapy delivery, the prognosis of lung cancer remains poor. Higher doses of radiation have been associated with improved outcomes but may result in higher toxicities. Respiratory gated radiotherapy (RGRT) has the potential to reduce pulmonary toxicity but there are significant limitations and pitfalls to its use. The aim of this article is to (i) describe the RGRT technique currently employed at Nepean and Westmead Hospitals; (ii) discuss the practical issues of implementing such a program; (iii) present the results of our RGRT program and (iv) review the potential uncertainties in using this technique and the methods we have used to overcome these. METHODS: A retrospective review of all patients who had a 4D-computed tomography (4D-CT) scan was undertaken. Records from treatment planning systems were used to assess the prospective gating program. RESULTS: Between September 2007 and June 2011, 53 patients at Nepean and 26 patients at Westmead Hospital underwent a 4D-CT. Between April and August 2011, 26 patients at Westmead Hospital underwent a prospective 4D-CT scan as treatment verification. Two of the 26 patients (7.7%) were found to have incomplete coverage of the planning target volume. Both patients underwent respiratory re-coaching, alleviating the need for replanning. CONCLUSION: RGRT may reduce doses to organs at risk with the potential for dose escalation. However its implementation requires significant staff training, treatment time and resources. Treatment verification with image guided radiation therapy are essential for safe delivery. PMID:23298326

Hau, Eric; Rains, Melissa; Pham, Trang; Muirhead, Rebecca; Yeghiaian Alvandi, Roland

2013-01-01

152

Bacterial inclusion bodies as potential synthetic devices for pathogen recognition and a therapeutic substance release  

PubMed Central

Background Adhesins of pathogens recognise the glycans on the host cell and mediate adherence. They are also crucial for determining the tissue preferences of pathogens. Currently, glyco-nanomaterials provide potential tool for antimicrobial therapy. We demonstrate that properly glyco-tailored inclusion bodies can specifically bind pathogen adhesins and release therapeutic substances. Results In this paper, we describe the preparation of tailored inclusion bodies via the conjugation of indicator protein aggregated to form inclusion bodies with soluble proteins. Whereas the indicator protein represents a remedy, the soluble proteins play a role in pathogen recognition. For conjugation, glutaraldehyde was used as linker. The treatment of conjugates with polar lysine, which was used to inactivate the residual glutaraldehyde, inhibited unwanted hydrophobic interactions between inclusion bodies. The tailored inclusion bodies specifically interacted with the SabA adhesin from Helicobacter pylori aggregated to form inclusion bodies that were bound to the sialic acids decorating the surface of human erythrocytes. We also tested the release of indicator proteins from the inclusion bodies using sortase A and Ssp DNAB intein self-cleaving modules, respectively. Sortase A released proteins in a relatively short period of time, whereas the intein cleavage took several weeks. Conclusions The tailored inclusion bodies are promising “nanopills” for biomedical applications. They are able to specifically target the pathogen, while a self-cleaving module releases a soluble remedy. Various self-cleaving modules can be enabled to achieve the diverse pace of remedy release.

2013-01-01

153

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

PubMed Central

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.

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

154

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

PubMed

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. PMID:18697592

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

2007-12-01

155

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

PubMed

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. PMID:10506013

Blaikie, L; Basketter, D A

1999-08-01

156

Comparison of the Luminex xTAG Respiratory Viral Panel with In-House Nucleic Acid Amplification Tests for Diagnosis of Respiratory Virus Infections  

Microsoft Academic Search

Detection of respiratory viruses using sensitive real-time nucleic acid amplification tests (NATs) is invalu- able for patient and outbreak management. However, the wide range of potential respiratory virus pathogens makes testing using individual real-time NATs expensive and laborious. The objective of this study was to compare the detection of respiratory virus targets using the Luminex xTAG respiratory viral panel (RVP)

Kanti Pabbaraju; Kara L. Tokaryk; Sallene Wong; Julie D. Fox

2008-01-01

157

Bartonella Infection in Animals: Carriership, Reservoir Potential, Pathogenicity, and Zoonotic Potential for Human Infection  

PubMed Central

Recent observations have begun to support a role for Bartonella spp. as animal as well as human pathogens. Bartonella spp. are vector-transmitted, blood-borne, intracellular, gram-negative bacteria that can induce prolonged infection in the host. Persistent infections in domestic and wild animals result in a substantial reservoir of Bartonella organisms in nature that can serve as a source for inadvertent human infection. The prevalence of bacteremia can range from 50 to 95% in selected rodent, cat, deer, and cattle populations. Dogs infected with Bartonella spp. can develop lameness, endocarditis, granulomatous lymphadenitis, and peliosis hepatis, lesions that have also been reported in association with human infection. Understanding the role of Bartonella spp. as pathogens in cats and other wild or domestic animals awaits the results of additional studies. Considering the extensive animal reservoirs and the large number of insects that have been implicated in the transmission of Bartonella spp., both animal and human exposure to these organisms may be more substantial than is currently believed.

Breitschwerdt, Edward B.; Kordick, Dorsey L.

2000-01-01

158

Herbaspirillum species: a potential pathogenic bacteria isolated from acute lymphoblastic leukemia patient.  

PubMed

Herbaspirillum species, colonized the plant rhizosphere, also called rhizobacteria, are plant growth-promoting bacteria. Recently we isolated Herbaspirillum from blood cultures of acute lymphoblastic leukemia (ALL) and identified by PCR and gene sequencing. Herbaspirillum may be a potential pathogenic bacteria. Although the exact role that these species play in ALL patients is unknown, their differentiation from other species has serious implications for clinical care and patient well-being. PMID:20625732

Chen, Jianguo; Su, Zhaoliang; Liu, Yingzhao; Sandoghchian, Siamak; Zheng, Dong; Wang, Shengjun; Xu, Huaxi

2010-07-13

159

Possible pathogens of social wasps (Hymenoptera: Vespidae) and their potential as biological control agents  

Microsoft Academic Search

No practical methods are currently available for area?wide, long?term control of social wasps in New Zealand. Pathogens have received little attention as potential control agents. Records from wasps of the genera Vespula, Vespa, and Dolicho?vespula and their associated nest material include 50 fungal, 12 bacterial, 5–7 nematode, 4 protozoan, and 2 viral species, although few have been confirmed through bioassay

E. A. F. Rose; R. J. Harris; T. R. Glare

1999-01-01

160

Effect of Carbon Dioxide on Testing of Susceptibilities of Respiratory Tract Pathogens to Macrolide and Azalide Antimicrobial Agents  

Microsoft Academic Search

The in vitro activities of erythromycin, azithromycin, and clarithromycin against 178 clinical isolates from the lower respiratory tract of patients with chronic obstructive pulmonary disease were determined by an agar dilution method. The plates were incubated in air alone or in 5% carbon dioxide. The MICs measured in air alone were lower for most isolates than those measured in 5%

M. M. JOHNSON; S. L. HILL; LAURA J. V. PIDDOCK

1999-01-01

161

Antibiotic resistance patterns among respiratory pathogens at a german university children’s hospital over a period of 10 years  

Microsoft Academic Search

Growing antimicrobial resistance among Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis is raising major concern worldwide. Strains of S. pneumoniae, H. influenzae and M. catarrhalis isolated from children with respiratory tract as well as invasive infection in a South-Western region of Germany between 1993 and 2002 were tested for susceptibility to common antibiotics including penicillins, cephalosporins and macrolides. A total

Sandra J. Arri; Kirsten Fluegge; Urban Mueller; Reinhard Berner

2006-01-01

162

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

PubMed Central

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.

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

2013-01-01

163

Mitochondrial respiratory pathways inhibition in Rhizopus oryzae potentiates activity of posaconazole and itraconazole via apoptosis.  

PubMed

The incidence of mucormycosis has increased drastically in immunocompromised patients. Also the array of targets whose inhibition results in Mucorales death is limited. Recently, researchers identified mitochondria as important regulators of detoxification and virulence mechanisms in fungi. In this context, targeting the mitochondrial respiratory chain may provide a new platform for antifungal development. We hypothesized that targeting respiratory pathways potentiates triazoles activity via apoptosis. We found that simultaneous administration of antimycin A (AA) and benzohydroxamate (BHAM), inhibitors of classical and alternative mitochondrial pathways respectively, resulted in potent activity of posaconazole (PCZ) and itraconazole (ICZ) against Rhizopus oryzae. We observed cellular changes characteristic of apoptosis in R. oryzae cells treated with PCZ or ICZ in combination with AA and BHAM. The fungicidal activity of this combination against R. oryzae was correlated with intracellular reactive oxygen species accumulation (ROS), phosphatidylserine externalization, mitochondrial membrane depolarization, and increased caspase like activity. DNA fragmentation and condensation assays also revealed apoptosis of R. oryzae cells. These apoptotic features were prevented by the addition of the ROS scavenger N-acetyl-cysteine. Taken together, these findings suggest that the use of PCZ or ICZ in combination with AA and BHAM makes R. oryzae exquisitely sensitive to treatment with triazoles via apoptosis. This strategy may serve as a new model for the development of improved or novel antifungal agents. PMID:23696824

Shirazi, Fazal; Kontoyiannis, Dimitrios P

2013-05-17

164

Carcinoembryonic antigen-related cell adhesion molecule (CEACAM)-binding recombinant polypeptide confers protection against infection by respiratory and urogenital pathogens.  

PubMed

The human-specific pathogens Neisseria meningitidis, N. gonorrhoea, Haemophilus influenzae and Moraxella catarrhalis share the property of targeting the carcinoembryonic antigen (CEA)-related cell adhesion molecules (CEACAMs) expressed on human epithelia. CEACAMs are signalling receptors implicated in cell adhesion and regulation of several physiological functions. Their targeting by pathogens can lead to tissue invasion. Although the CEACAM-binding ligands of the bacteria are structurally diverse, they target a common site on the receptor. We have generated a recombinant polypeptide that blocks the interactions of the mucosal pathogens with human epithelial cells and antibodies against it inhibit M. catarrhalis interactions with the receptor. As such, it is a potential antimicrobial agent to prevent infection via a strategy unlikely to promote bacterial resistance and a vaccine candidate against M. catarrhalis. In addition, it could serve more widely as a novel research tool and as a potential therapeutic agent in CEACAM-based physiological disorders. PMID:15720557

Hill, Darryl J; Edwards, Andrew M; Rowe, Helen A; Virji, Mumtaz

2005-03-01

165

Mannose-Binding Lectin Deficiency and Respiratory Tract Infection  

Microsoft Academic Search

Mannose-binding lectin (MBL) is an innate immune system pattern recognition protein that kills a wide range of pathogenic microbes through complement activation. A substantial proportion of all human populations studied to date have MBL deficiency due to MBL2 polymorphisms, which potentially increases susceptibility to infectious disease. MBL binds numerous respiratory pathogens but the capsule of Streptococcus pneumoniae abrogates its efficient

Damon P. Eisen

2010-01-01

166

In Vitro Activities of a Streptogramin (RP59500), Three Macrolides, and an Azalide against Four Respiratory Tract Pathogens  

Microsoft Academic Search

Broth microdilution tests were carried out with 2,671 respiratory tract isolates from 19 medical centers throughout the continental United States. The tests compared a streptogramin (RP59500) to erythromycin, dirithromycin, clarithromycin, and azithromycin against Streptococcus pneumoniae, S. pyogenes, Haemophilus influenzae,andMoraxellacatarrhalis.Againstmacrolide-susceptiblestrains,thepotencyofRP59500wassimilar to that of the macrolides: the azalide, azithromycin, was two to four times more potent againstH. influenzae. The azalide and three

A. L. BARRY; C. FUCHS

1995-01-01

167

Broad Spectrum Respiratory Pathogen Analysis of Throat Swabs from Military Recruits Reveals Interference Between Rhinoviruses and Adenoviruses  

Microsoft Academic Search

Military recruits experience a high incidence of febrile respiratory illness (FRI), leading to significant morbidity and lost\\u000a 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\\u000a etiology of the remaining cases is unclear. In this study, we explore the carriage rates and

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

2010-01-01

168

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

PubMed

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. PMID:23224412

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

2012-12-09

169

Evidence that orthotopic transposition following rat heterotopic small bowel transplantation corrects overgrowth of potentially pathogenic bacteria.  

PubMed

An overgrowth of pathogenic organisms occurs following rat heterotopic small bowel transplantation. This study assessed whether the bacterial microflora return to normal following subsequent orthotopic transposition of the graft. After 14 days the heterotopic graft was placed into continuity following resection of 15 cm of the host midintestinal loop. Quantitative and qualitative analyses of the intraluminal bacteria were performed studying the resected host intestine, the heterotopic graft at 14 days, and the graft 14 days after transposition. A group of normal rats were used as controls. An overgrowth of Staphylococcus epidermidis evident in the heterotopic graft at 14 days returned to a more normal bacterial profile following orthotopic transposition. These findings suggest that early interposition of a small bowel graft into an orthotopic position may prevent an alteration in the small bowel ecology toward potentially pathogenic organisms capable of translocation. PMID:8610395

Price, B A; Cumberland, N S; Clark, C L; Pockley, A G; Wood, R F

1996-02-27

170

Molecular detection of CF lung pathogens: current status and future potential.  

PubMed

Molecular diagnostic tests, based on the detection and identification of nucleic acids in human biological samples, are increasingly employed in the diagnosis of infectious diseases and may be of future benefit to CF microbiology services. Our growing understanding of the complex polymicrobial nature of CF airway infection has highlighted current and likely future shortcomings in standard diagnostic practices. Failure to detect fastidious or slow growing microbes and misidentification of newly emerging pathogens could potentially be addressed using culture-independent molecular technologies with high target specificity. This review considers existing molecular diagnostic tests in the context of the key requirements for an envisaged CF microbiology focussed assay. The issues of assay speed, throughput, detection of multiple pathogens, data interpretation and antimicrobial susceptibility testing are discussed. PMID:23402821

Pattison, Sally H; Rogers, Geraint B; Crockard, Martin; Elborn, J Stuart; Tunney, Michael M

2013-02-10

171

Systems Integration of Biodefense Omics Data for Analysis of Pathogen-Host Interactions and Identification of Potential Targets  

Microsoft Academic Search

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.

Peter B. McGarvey; Hongzhan Huang; Raja Mazumder; Jian Zhang; Yongxing Chen; Chengdong Zhang; Stephen Cammer; Rebecca Will; Margie Odle; Bruno Sobral; Margaret Moore; Cathy H. Wu; Jörg Hoheisel

2009-01-01

172

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

PubMed Central

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.

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

2012-01-01

173

Minimum inhibitory concentrations of tulathromycin against respiratory bacterial pathogens isolated from clinical cases in European cattle and swine and variability arising from changes in in vitro methodology.  

PubMed

The in vitro activity of tulathromycin was evaluated against common bovine and porcine respiratory pathogens collected from outbreaks of clinical disease across eight European countries from 1998 to 2001. Minimum inhibitory concentrations (MICs) for one isolate of each bacterial species from each outbreak were determined using a broth microdilution technique. The lowest concentrations inhibiting the growth of 90% of isolates (MIC90) for tulathromycin were 2 microg/ml for Mannheimia (Pasteurella) haemolytica, 1 microg/ml for Pasteurella multocida (bovine), and 2 microg/ml for Pasteurella multocida (porcine) and ranged from 0.5 to 4 microg/ml for Histophilus somni (Haemophilus somnus) and from 4 to 16 microg/ml for Actinobacillus pleuropneumoniae. Isolates were retested in the presence of serum. The activity of tulathromycin against fastidious organisms was affected by culture conditions, and MICs were reduced in the presence of serum. PMID:16094559

Godinho, Kevin S; Keane, Sue G; Nanjiani, Ian A; Benchaoui, Hafid A; Sunderland, Simon J; Jones, M Anne; Weatherley, Andrew J; Gootz, Thomas D; Rowan, Tim G

2005-01-01

174

Spectrum and potency of ceftaroline against leading pathogens causing community-acquired respiratory tract and skin and soft tissue infections in Latin America, 2010.  

PubMed

Ceftaroline, the active metabolite of the prodrug ceftaroline fosamil, is a cephalosporin with in vitro bactericidal activity against Gram-positive organisms, including methicillin-susceptible and -resistant Staphylococcus aureus, ?-haemolytic and viridans group streptococci, and Streptococcus pneumoniae, as well as common Gram-negative organisms. In this study a total of 986 isolates collected in 2010 from patients in 15 medical centers in five Latin American countries from the Assessing Worldwide Antimicrobial Resistance Evaluation Program were identified as community-acquired respiratory tract or skin and soft tissue infection pathogens. Ceftaroline was the most potent agent tested against S. pneumoniae with a MIC90 value (0.12?g/mL) that was eight-fold lower than ceftriaxone, levofloxacin, and linezolid. Its spectrum of coverage (100.0% susceptible) was similar to tigecycline, linezolid, levofloxacin and vancomycin. Against Haemophilus influenzae and Moraxella catarrhalis, ceftaroline was the most active agent tested. The activity of ceftaroline against S. aureus (including MRSA) was similar to that of vancomycin and tetracycline (MIC90, 1?g/mL) and linezolid (MIC90, 2?g/mL). The ?-haemolytic streptococci exhibited 100.0% susceptibility to ceftaroline. Ceftaroline activity against Escherichia coli, Klebsiella spp., and Enterobacter spp. was similar to that of ceftriaxone and ceftazidime. These parenteral cephalosporin agents have potent activity against non-extended-spectrum ?-lactamase-phenotype strains, but are not active against extended-spectrum ?-lactamase-phenotype strains. These results confirm the in vitro activity of ceftaroline against pathogens common in community-acquired respiratory tract and skin and soft tissue infection in Latin America, and suggest that ceftaroline fosamil could be an important therapeutic option for these infections. PMID:23916453

Flamm, Robert K; Sader, Helio S; Jones, Ronald N

2013-07-31

175

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

PubMed Central

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.

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

2011-01-01

176

Genotyping of Environmental and Clinical Stenotrophomonas maltophilia Isolates and their Pathogenic Potential  

PubMed Central

Stenotrophomonas maltophilia is a highly versatile species with useful biotechnological potential but also with pathogenic properties. In light of possible differences in virulence characteristics, knowledge about genomic subgroups is therefore desirable. Two different genotyping methods, rep-PCR fingerprinting and partial gyrB gene sequencing were used to elucidate S. maltophilia intraspecies diversity. Rep-PCR fingerprinting revealed the presence of 12 large subgroups, while gyrB gene sequencing distinguished 10 subgroups. For 8 of them, the same strain composition was shown with both typing methods. A subset of 59 isolates representative for the gyrB groups was further investigated with regards to their pathogenic properties in a virulence model using Dictyostelium discoideum and Acanthamoeba castellanii as host organisms. A clear tendency towards accumulation of virulent strains could be observed for one group with A. castellanii and for two groups with D. discoideum. Several virulent strains did not cluster in any of the genetic groups, while other groups displayed no virulence properties at all. The amoeba pathogenicity model proved suitable in showing differences in S. maltophilia virulence. However, the model is still not sufficient to completely elucidate virulence as critical for a human host, since several strains involved in human infections did not show any virulence against amoeba.

Adamek, Martina; Overhage, Jorg; Bathe, Stephan; Winter, Josef; Fischer, Reinhard; Schwartz, Thomas

2011-01-01

177

Modelling the co-occurrence of Streptococcus pneumoniae with other bacterial and viral pathogens in the upper respiratory tract.  

PubMed

Otitis media (OM) is a major burden for all children, particularly for Australian Aboriginal children. Streptococcus pneumoniae, Moraxella catarrhalis, Haemophilus influenzae and viruses (including rhinovirus and adenovirus) are associated with OM. We investigated nasopharyngeal microbial interactions in 435 samples collected from 79 Aboriginal and 570 samples from 88 non-Aboriginal children in Western Australia. We describe a multivariate random effects model appropriate for analysis of longitudinal data, which enables the identification of two independent levels of correlation between pairs of pathogens. At the microbe level, rhinovirus infection was positively correlated with carriage of S. pneumoniae, H. influenzae and M. catarrhalis, and adenovirus with M. catarrhalis. Generally, there were positive associations between bacterial pathogens at both the host and microbe level. Positive viral-bacterial associations at the microbe level support previous findings indicating that viral infection can predispose an individual to bacterial carriage. Viral vaccines may assist in reducing the burden of bacterial disease. PMID:17030494

Jacoby, Peter; Watson, Kelly; Bowman, Jacinta; Taylor, Amanda; Riley, Thomas V; Smith, David W; Lehmann, Deborah

2006-09-22

178

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

PubMed

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. PMID:22633481

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

2012-04-17

179

Potentially Pathogenic Bacteria in Shower Water and Air of a Stem Cell Transplant Unit?  

PubMed Central

Potential pathogens from shower water and aerosolized shower mist (i.e., shower aerosol) have been suggested as an environmental source of infection for immunocompromised patients. To quantify the microbial load in shower water and aerosol samples, we used culture, microscopic, and quantitative PCR methods to investigate four shower stalls in a stem cell transplant unit at Barnes-Jewish Hospital in St. Louis, MO. We also tested membrane-integrated showerheads as a possible mitigation strategy. In addition to quantification, a 16S rRNA gene sequencing survey was used to characterize the abundant bacterial populations within shower water and aerosols. The average total bacterial counts were 2.2 × 107 cells/liter in shower water and 3.4 × 104 cells/m3 in shower aerosol, and these counts were reduced to 6.3 × 104 cells/liter (99.6% efficiency) and 8.9 × 103 cells/m3 (82.4% efficiency), respectively, after membrane-integrated showerheads were installed. Potentially pathogenic organisms were found in both water and aerosol samples from the conventional showers. Most notable was the presence of Mycobacterium mucogenicum (99.5% identity) in the water and Pseudomonas aeruginosa (99.3% identity) in the aerosol samples. Membrane-integrated showerheads may protect immunocompromised patients from waterborne infections in a stem cell transplant unit because of efficient capture of vast numbers of potentially pathogenic bacteria from hospital water. However, an in-depth epidemiological study is necessary to investigate whether membrane-integrated showerheads reduce hospital-acquired infections. The microbial load in shower aerosols with conventional showerheads was elevated compared to the load in HEPA-filtered background air in the stem cell unit, but it was considerably lower than typical indoor air. Thus, in shower environments without HEPA filtration, the increase in microbial load due to shower water aerosolization would not have been distinguishable from anticipated variations in background levels.

Perkins, Sarah D.; Mayfield, Jennie; Fraser, Victoria; Angenent, Largus T.

2009-01-01

180

Diagnostic potential of the pulsed discharged helium ionization detector (PDHID) for pathogenic Mycobacterial volatile biomarkers.  

PubMed

Pathogenic Mycobacteria cause diseases in animals and humans with significant economic and societal consequences. Current methods for Mycobacterial detection relies upon time- and labor-intensive techniques such as culturing or DNA analysis. Using gas chromatography and mass spectrometry, four volatile compounds (methyl phenylacetate, methyl p-anisate, methyl nicotinate and o-phenyl anisole) were recently proposed as potential biomarkers for Mycobacteria. We demonstrate for the first time the capabilities of a field-deployable, pulsed discharge helium ionization detector (PDHID) for sensing these volatiles. We determined the analytical performance of the PDHID toward these Mycobacterial volatiles. Detector performance was moderately affected over the temperature range of 150 to 350 °C. The linear dynamic range for all four analytes exceeded three orders of magnitude. The limits of detection (LOD) and quantitation (LOQ) were calculated as 150 and 450 pg respectively, for all compounds, except methyl phenylacetate (LOD and LOQ, 90 and 270 pg, respectively). Control charts revealed that the PDHID detection system was generally stable, and deviations could be traced to common causes and excluded special causes. Grob tests and ionization potential data suggest that the PDHID is capable of detecting Mycobacterial volatiles in a complex milieu such as culture headspace or breath samples from tuberculosis patients. The diagnostic potential of the PDHID is critical to our goal of a handheld, field-deployable 'sniffer' system for biological pathogens and chemical warfare agents. PMID:23867723

Manginell, Ronald P; Pimentel, Adam S; Mowry, Curtis D; Mangan, Michael A; Moorman, Matthew W; Allen, Amy; Schares, Elizabeth S; Achyuthan, Komandoor E

2013-07-18

181

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

PubMed

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. PMID:14627303

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

2003-11-01

182

Detection of antibodies to a pathogenic mycoplasma in desert tortoises (Gopherus agassizii) with upper respiratory tract disease.  

PubMed Central

Mycoplasma agassizii (proposed species novum) is the etiologic agent of an upper respiratory tract disease in the desert tortoise (Gopherus agassizii), which is threatened in most of its range. An enzyme-linked immunosorbent assay (ELISA) for the detection of M. agassizii-specific antibodies in desert tortoises was developed with a monoclonal antibody with specificity for desert tortoise immunoglobulin light chain. Plasma samples from one group of tortoises were tested immediately before and 1 month after challenge either with nasal exudate containing M. agassizii or with a purified preparation of M. agassizii. Plasma samples from a second group of known healthy and sick tortoises were also tested. In the first group, the ELISA detected seroconversion in individual tortoises following challenge with M. agassizii. In the second group, ELISA results were positively correlated with the health status of the tortoises, as determined by clinical and pathologic findings. In addition, the ELISA revealed that tortoise antimycoplasma antibodies were specific for M. agassizii when samples were assayed against M. agassizii, M. pulmonis, M. testudinis, and M. gallisepticum antigens. The observed direct correlation between the presence of nasal mucosal lesions and M. agassizii-specific antibodies proved that the ELISA reliably diagnosed M. agassizii infection in desert tortoises and advocates its use for monitoring M. agassizii-induced upper respiratory tract disease in free-ranging desert tortoises. Images

Schumacher, I M; Brown, M B; Jacobson, E R; Collins, B R; Klein, P A

1993-01-01

183

Highly pathogenic porcine reproductive and respiratory syndrome virus impairs LPS- and poly(I:C)-stimulated tumor necrosis factor-alpha release by inhibiting ERK signaling pathway.  

PubMed

Atypical porcine reproductive and respiratory syndrome (PRRS) characterized by high morbidity and mortality emerged in China in 2006. The causative agent was confirmed to be a highly pathogenic PRRS virus (HP-PRRSV). However, the pathogenesis of HP-PRRSV is still uncertain. Here, the ability of the highly pathogenic strains (HV and JX) to induce tumor necrosis factor alpha (TNF-?) was studied. Our results showed that HV and JX were weaker inducers of TNF-? than the conventional strain CH-1a. Moreover, HV infection was demonstrated to suppress extracellular signal-regulated kinase (ERK) phosphorylation at the early time points. Pharmacologic inhibition or activation of ERK revealed that TNF-? production in HV-infected macrophages was associated with the activation status of ERK. Furthermore, HV- and JX-infection could potently impair lipopolysaccharide (LPS)- and poly(I:C)-stimulated TNF-? release in a dose dependent manner whereas synergistic effects were observed at mRNA level. The observation suggested the involvement of posttranslational impact of HP-PRRSV on TNF-? production, which might be attributed to the reduced ERK1/2 phosphorylation in response to toll-like receptor (TLR)-ligation. Taken together, our results indicated that HP-PRRSV infection could impair TNF-? production by inhibiting ERK signaling pathway, which might partially contribute to the pathogenesis of HP-PRRSV. PMID:22497732

Hou, Jun; Wang, Lianghai; He, Weiyong; Zhang, Hexiao; Feng, Wen-hai

2012-04-03

184

Viability of respiratory pathogens cultured from nasopharyngeal swabs stored for up to 12 years at -70°C in skim milk tryptone glucose glycerol broth.  

PubMed

Nasopharyngeal carriage studies are needed to monitor changes in important bacterial pathogens in response to vaccination and antibiotics. The ability to store original specimens frozen in skim milk tryptone glucose glycerol broth (STGGB) allows additional studies to be conducted without the need for further expensive field collection. Although sub-cultured isolates remain viable in this medium for many years, limited data are available to indicate viability of relatively low numbers of organisms present in nasopharyngeal specimens stored frozen over long periods of time. We conducted several studies whereby swabs stored in STGGB at -70°C for up to 12 years were thawed and aliquots cultured. Recovery of Streptococcus pneumoniae (72% positive from 269 swabs), Haemophilus influenzae (62% from 214) and Moraxella catarrhalis (81% from 162) was not significantly different from the original cultures: 69% (Risk Difference [RD] 3.0, 95% Confidence Interval [CI] -4.7, 10.7), 66% (RD -4.7, 95% CI -13.8, 4.4) and 78% (RD 3.1, 95% CI -5.7, 11.9) positive respectively. There was no trend in recovery from swabs stored for increasing lengths of time. We conclude that studies which rely on the viability of these respiratory pathogens can be conducted using original swabs stored at -70°C for at least 12 years. PMID:21736904

Hare, Kim M; Smith-Vaughan, Heidi C; Leach, Amanda J

2011-06-28

185

Comparison of the Idaho Technology FilmArray System to Real-Time PCR for Detection of Respiratory Pathogens in Children  

PubMed Central

The FilmArray Respiratory Panel (RP) multiplexed nucleic acid amplification test (Idaho Technology, Inc., Salt Lake City, UT) was compared to laboratory-developed real-time PCR assays for the detection of various respiratory viruses and certain bacterial pathogens. A total of 215 frozen archived pediatric respiratory specimens previously characterized as either negative or positive for one or more pathogens by real-time PCR were examined using the FilmArray RP system. Overall agreement between the FilmArray RP and corresponding real-time PCR assays for shared analytes was 98.6% (kappa = 0.92 [95% confidence interval (CI), 0.89 to 0.94]). The combined positive percent agreement was 89.4% (95% CI, 85.4 to 92.6); the negative percent agreement was 99.6% (95% CI, 99.2 to 99.8). The mean real-time PCR threshold cycle (CT) value for specimens with discordant results was 36.46 ± 4.54. Detection of coinfections and correct identification of influenza A virus subtypes were comparable to those of real-time PCR when using the FilmArray RP. The greatest comparative difference in sensitivity was observed for adenovirus; only 11 of 24 (45.8%; 95% CI, 27.9 to 64.9) clinical specimens positive for adenovirus by real-time PCR were also positive by the FilmArray RP. In addition, upon testing 20 characterized adenovirus serotypes prepared at high and low viral loads, the FilmArray RP did not detect serotypes 6 and 41 at either level and failed to detect serotypes 2, 20, 35, and 37 when viral loads were low. The FilmArray RP system is rapid and extremely user-friendly, with results available in just over 1 h with almost no labor involved. Its low throughput is a significant drawback for laboratories receiving large numbers of specimens, as only a single sample can be processed at a time with one instrument.

Pierce, Virginia M.; Elkan, Michael; Leet, Marilyn; McGowan, Karin L.

2012-01-01

186

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. ...

187

Upper airway afferents are sufficient to evoke the early components of respiratory-related cortical potentials in humans.  

PubMed

Repeated inspiratory occlusions in humans elicit respiratory-related cortical potentials, the respiratory counterpart of somatosensory-evoked potentials. These potentials comprise early components (stimulus detection) and late components (cognitive processing). They are considered as the summation of several afferent activities from various part of the respiratory system. This study assesses the role of the upper airway as a determinant of the early and late components of the potentials, taking advantage of the presence of a tracheotomy in patients totally or partially deafferented. Eight patients who could breathe either through the mouth or through a tracheotomy orifice (whole upper airway bypassed) were studied (4 quadriplegic patients with phrenic pacing, 4 patients with various sources of inspiratory pump dysfunction). Respiratory-related evoked potentials were recorded in CZ-C3 and CZ-C4. They were consistently present after mouth occlusions, with a first positive P1 and a first negative N1 components of normal latencies (P1: 40.4 +/- 6.1 ms in CZ-C3 and 47.6 +/- 7.6 ms in CZ-C4; N1: 84.4 +/- 27.1 ms in CZ-C3 and 90.2 +/- 17.4 ms in CZ-C4) and amplitudes. Tracheal occlusions did not evoke any cortical activity. Therefore, in patients with inspiratory pump dysfunction, the activation of upper airway afferents is sufficient to produce the early components of the respiratory-related evoked cortical potentials. Per contra, in this setting, pulmonary afferents do not suffice to evoke these components. PMID:15220304

Donzel-Raynaud, Christine; Straus, Christian; Bezzi, Michela; Redolfi, Stefania; Raux, Mathieu; Zelter, Marc; Derenne, Jean-Philippe; Similowski, Thomas

2004-06-25

188

Analysis of the swine tracheobronchial lymph node transcriptomic response to infection with a Chinese highly pathogenic strain of porcine reproductive and respiratory syndrome virus  

PubMed Central

Background Porcine reproductive and respiratory syndrome virus (PRRSV) is a major pathogen of swine worldwide. Emergence in 2006 of a novel highly pathogenic PRRSV (HP-PRRSV) isolate in China necessitated a comparative investigation into the host transcriptome response in tracheobronchial lymph nodes (TBLN) 13 days post-infection with HP-PRRSV rJXwn06, PRRSV strain VR-2332 or sham inocula. RNA from each was prepared for next-generation sequencing. Amplified library constructs were directly sequenced and a list of sequence transcripts and counts was generated using an RNAseq analysis pipeline to determine differential gene expression. Transcripts were annotated and relative abundance was calculated based upon the number of times a given transcript was represented in the library. Results Major changes in transcript abundance occurred in response to infection with either PRRSV strain, each with over 630 differentially expressed transcripts. The largest increase in transcript level for either virus versus sham-inoculated controls were three serum amyloid A2 acute-phase isoforms. However, the degree of up or down-regulation of transcripts following infection with HP-PRRSV rJXwn06 was greater than transcript changes observed with US PRRSV VR-2332. Also, of 632 significantly altered transcripts within the HP-PRRSV rJXwn06 library 55 were up-regulated and 69 were down-regulated more than 3-fold, whilst in the US PRRSV VR-2332 library only 4 transcripts were up-regulated and 116 were down-regulated more than 3-fold. Conclusions The magnitude of differentially expressed gene profiles detected in HP-PRRSV rJXwn06 infected pigs as compared to VR-2332 infected pigs was consistent with the increased pathogenicity of the HP-PRRSV in vivo.

2012-01-01

189

[The development of a rapid loop-mediated indirect PCR method for detection and differentiation of highly and lowly pathogenic porcine reproductive and respiratory syndrome virus].  

PubMed

The aim of this study is to establish the method of loop-mediated indirect PCR assay for detection of Reproductive and Respiratory Syndrome Virus (PRRSV) infection and differentiation of highly pathogenic PRRSV (HP-PRRSV) and lowly pathogenic PRRSV (LP-PRRSV). Based on the alignments of ORF2 gene sequences and ORFla gene sequences of PRRSV Chinese isolates deposited in GenBank, two pairs of specific probes were designed and labeled to both ends of the soybean Lectin gene fragment by PCR, respectively. The probe-labeled soybean Lectin genes were used to be reporter genes for detection and differentiation of PRRSV. After one round strand displacement reaction, the reporter genes were amplified by reverse PCR. The specific PCR products were 193bp, 355bp for HP-PRRSV and 193bp, 442bp for LP-PRRSV, respectively. The method could detect 5. 6 TCID50/mL LP-PRRSV RNA and 18 TCIDs0/ mL HP-PRRSV RNA, and co-infection did not affect detection sensitivity. No amplification was observed with other porcine originated pathogens including CSFV, PPV, PRV, PCV2, ETEC and Haemophilus parasui. Twenty clinical samples were used for comparative testing with conventional PCR. Fourteen samples were found positive for PRRSV by the loop-mediated indirect PCR, of which 4 were LP-PRRSV, 9 HP-PRRSV and 1 LP/HP-PRRSV co-infection, consistent with the conventional PCR test results. In conclusion, the loop-mediated indirect PCR is a simple, rapid, sensitive and specific etiologic diagnosis tool, and suitable for the differential diagnosis of HP/LP-PRRSV, especially for identification of mixed infection of HP/LP-PRRSV. PMID:23894998

Zheng, Ming; Li, Hua-Wei; Bian, Chuan-Zhou; Wang, Yong-Fen; Wang, Lao-Qi

2013-06-01

190

Climate Change and the Potential Spreading of Marine Mucilage and Microbial Pathogens in the Mediterranean Sea  

PubMed Central

Background Marine snow (small amorphous aggregates with colloidal properties) is present in all oceans of the world. Surface water warming and the consequent increase of water column stability can favour the coalescence of marine snow into marine mucilage, large marine aggregates representing an ephemeral and extreme habitat. Marine mucilage characterize aquatic systems with altered environmental conditions. Methodology/Principal Findings We investigated, by means of molecular techniques, viruses and prokaryotes within the mucilage and in surrounding seawater to examine the potential of mucilage to host new microbial diversity and/or spread marine diseases. We found that marine mucilage contained a large and unexpectedly exclusive microbial biodiversity and hosted pathogenic species that were absent in surrounding seawater. We also investigated the relationship between climate change and the frequency of mucilage in the Mediterranean Sea over the last 200 years and found that the number of mucilage outbreaks increased almost exponentially in the last 20 years. The increasing frequency of mucilage outbreaks is closely associated with the temperature anomalies. Conclusions/Significance We conclude that the spreading of mucilage in the Mediterranean Sea is linked to climate-driven sea surface warming. The mucilage can act as a controlling factor of microbial diversity across wide oceanic regions and could have the potential to act as a carrier of specific microorganisms, thereby increasing the spread of pathogenic bacteria.

Danovaro, Roberto; Fonda Umani, Serena; Pusceddu, Antonio

2009-01-01

191

In vitro antibacterial potential of Eugenia jambolana seed extracts against multidrug-resistant human bacterial pathogens.  

PubMed

The present study was carried out to evaluate the possible in vitro antibacterial potential of extracts of Eugenia jambolana seeds against multidrug-resistant human bacterial pathogens. Agar well diffusion and microbroth dilution assay methods were used for antibacterial susceptibility testing. Kill-kinetics study was done to know the rate and extent of bacterial killing. Phytochemical analysis and TLC-bioautography were performed by colour tests to characterize the putative compounds responsible for this antibacterial activity. Cytotoxic potential was evaluated on human erythrocytes by haemolytic assay method and acute oral toxicity study was done in mice. The plant extracts demonstrated varying degrees of strain specific antibacterial activity against all the test isolates. Further, ethyl acetate fraction obtained from fractionation of most active ethanol extract showed maximum antibacterial effect against all the test isolates. Phytochemical analysis and TLC-bioautography of ethyl acetate fraction revealed that phenolics were the major active phytoconstituents. Ethyl acetate fraction also demonstrated no haemolytic activity on human erythrocytes and no gross behavioural changes as well as toxic symptoms were observed in mice at recommended dosage level. The results provide justification for the use of E. jambolana in folk medicine to treat various infectious diseases and may contribute to the development of novel antimicrobial agents for the treatment of infections caused by these drug-resistant bacterial pathogens. PMID:22444436

Bag, Anwesa; Bhattacharyya, Subir Kumar; Pal, Nishith Kumar; Chattopadhyay, Rabi Ranjan

2012-03-22

192

Potential therapeutic implications of new insights into respiratory syncytial virus disease  

Microsoft Academic Search

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

Peter JM Openshaw

2002-01-01

193

Respiratory displacement of the thoracic aorta: physiological phenomenon with potential implications for thoracic endovascular repair.  

PubMed

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. PMID:19434450

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

2009-05-12

194

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

SciTech Connect

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.

Weber, Tim Frederik, E-mail: tim.weber@med.uni-heidelberg.d [University Medical Center Heidelberg, Department of Diagnostic and Interventional Radiology (Germany); Tetzlaff, Ralf [German Cancer Research Center, Department of Radiology (Germany); Rengier, Fabian [University Medical Center Heidelberg, Department of Diagnostic and Interventional Radiology (Germany); Geisbuesch, Philipp [University Medical Center Heidelberg, Department of Vascular and Endovascular Surgery (Germany); Kopp-Schneider, Annette [German Cancer Research Center, Department of Biostatistics (Germany); Boeckler, Dittmar [University Medical Center Heidelberg, Department of Vascular and Endovascular Surgery (Germany); Eichinger, Monika [German Cancer Research Center, Department of Radiology (Germany); Kauczor, Hans-Ulrich [University Medical Center Heidelberg, Department of Diagnostic and Interventional Radiology (Germany); Tengg-Kobligk, Hendrik von [German Cancer Research Center, Department of Radiology (Germany)

2009-07-15

195

Potential anti-respiratory syncytial virus lead compounds from Aglaia species.  

PubMed

Although the global prevalence of respiratory syncytial virus (RSV) infection, especially among infants and young children is on the increase, there are only limited therapeutic options for treatment of this disease. Therefore, the search for novel antiviral inhibitors of RSV has become more intensive. In a pilot screening of eighteen compounds from various Aglaia species for anti-RSV activity, we identified dammarenolic acid (ignT1), aglaiol (dupT1) and niloticin (cucT1) as potential anti-RSV compounds, with ignT1 being the most potent. Methylation of ignT1 results in a complete loss of anti-RSV activity. Time of addition studies reveal that both ignT1 and dupT1 target the RSV replication at a post-entry stage, although ignT1 was more potent. Dammarenolic acid (ignT1) was also more cytotoxic than aglaiol (dupT1). By carrying out parallel anti-RSV screening with aphidicolin (a highly cytotoxic diterpenoid) and ignT1, we showed that although aphidicolin was more cytotoxic than ignT1, it had virtually no anti-RSV activity. Therefore, dammarenolic acid, aglaiol and niloticin demonstrate potent anti-RSV activity that shouldbe explored further in the current search for anti-RSV therapeutic agents. PMID:18972843

Esimone, C O; Eck, G; Duong, T N; Uberla, K; Proksch, P; Grunwald, T

2008-10-01

196

Antifungal Susceptibility Profiles of 1698 Yeast Reference Strains Revealing Potential Emerging Human Pathogens  

PubMed Central

New molecular identification techniques and the increased number of patients with various immune defects or underlying conditions lead to the emergence and/or the description of novel species of human and animal fungal opportunistic pathogens. Antifungal susceptibility provides important information for ecological, epidemiological and therapeutic issues. The aim of this study was to assess the potential risk of the various species based on their antifungal drug resistance, keeping in mind the methodological limitations. Antifungal susceptibility profiles to the five classes of antifungal drugs (polyens, azoles, echinocandins, allylamines and antimetabolites) were determined for 1698 yeast reference strains belonging to 992 species (634 Ascomycetes and 358 Basidiomycetes). Interestingly, geometric mean minimum inhibitory concentrations (MICs) of all antifungal drugs tested were significantly higher for Basidiomycetes compared to Ascomycetes (p<0.001). Twenty four strains belonging to 23 species of which 19 were Basidiomycetes seem to be intrinsically “resistant” to all drugs. Comparison of the antifungal susceptibility profiles of the 4240 clinical isolates and the 315 reference strains belonging to 53 shared species showed similar results. Even in the absence of demonstrated in vitro/in vivo correlation, knowing the in vitro susceptibility to systemic antifungal agents and the putative intrinsic resistance of yeast species present in the environment is important because they could become opportunistic pathogens.

Desnos-Ollivier, Marie; Robert, Vincent; Raoux-Barbot, Dorothee; Groenewald, Marizeth; Dromer, Francoise

2012-01-01

197

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

PubMed

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

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

2012-09-12

198

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

PubMed Central

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.

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

199

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...

200

Susceptibility of New Zealand flora to Phytophthora ramorum and pathogen sporulation potential: an approach based on the precautionary principle  

Microsoft Academic Search

Phytophthora ramorum, the cause of sudden oak death in the westernUSAand a damaging pathogen in Europe, is a biosecurity threat of unknown magnitude\\u000a to New Zealand and Australasia because of its presence in traded ornamental plants. Knowledge of potential hosts acting as\\u000a carriers and of symptoms caused by the pathogen on such hosts will strengthen precautionary quarantine regulations to prevent

D. Hüberli; B. Lutzy; B. Voss; M. Calver; M. Ormsby; M. Garbelotto

2008-01-01

201

Other viral pneumonias: coronavirus, respiratory syncytial virus, adenovirus, hantavirus.  

PubMed

Severe viral pneumonia is an increasing problem among adults. The incidence and number of viruses known to cause pneumonia and respiratory failure have also expanded in recent years. This article provides an overview of severe respiratory disease caused by coronavirus, respiratory syncytial virus, adenovirus, and hantavirus. These emerging pathogens are easily overlooked and timely diagnosis requires a high index of suspicion and confirmation by molecular testing. Management of individual cases is mainly supportive and requires institution of appropriate infection control measures. Vaccines and effective therapeutics for these potentially devastating respiratory viruses are urgently required. PMID:24094390

Lee, Nelson; Qureshi, Salman T

2013-08-09

202

[Potentially pathogenic fungi in the waters of the Charzykowskie Lake in Zaborski Landscape Park].  

PubMed

The occurrence of potentially pathogenic fungal strains in the Charzykowskie Lake and runnels flowing into and out of it was investigated. The study material was obtained in 2005 and in 2006, in the periods of spring intermix and summer stagnation, and in 2005 in the period of autumn intermix. The fungi found in the Charzykowski Lake belonged to 5 genera: Rhodotorula (R. minuta, R. rubra and R. glutinis), Cryptoccocus (C. neoformans, C. laurentii, C. terreus and C. laurentii), Candida (C. inconspicua, C. lusitaniae, C. tropicalis, C. pelliculosa, C. kefir, C. glabrata, C. inconspicua, C. parapsilosis, C. ciferrii and C. colliculosa), Trichosporon (T. cutaneum) and Klockera (K. apiculata). The fungi found in runnels flowing into and out of the Charzykowskie Lake belonged to 4 genera: Rhodotorula (R. rubra and R. glutinis), Cryptoccocus (C. laurentii, C. neoformans, C. albidus and C. terreus), Candida (C. colliculosa, C. lusitaniae, C. tropicalis, C. pelliculosa, C. cifferii, C. glabrata) and Trichosporon (T. cutaneum). PMID:17912806

Kurnatowski, Piotr; Rózga, Anna; Rózga, B?azei; Babski, Piotr; Wójcik, Anna

2007-01-01

203

Predatory Bacteria: A Potential Ally against Multidrug-Resistant Gram-Negative Pathogens  

PubMed Central

Multidrug-resistant (MDR) Gram-negative bacteria have emerged as a serious threat to human and animal health. Bdellovibrio spp. and Micavibrio spp. are Gram-negative bacteria that prey on other Gram-negative bacteria. In this study, the ability of Bdellovibrio bacteriovorus and Micavibrio aeruginosavorus to prey on MDR Gram-negative clinical strains was examined. Although the potential use of predatory bacteria to attack MDR pathogens has been suggested, the data supporting these claims is lacking. By conducting predation experiments we have established that predatory bacteria have the capacity to attack clinical strains of a variety of ß-lactamase-producing, MDR Gram-negative bacteria. Our observations indicate that predatory bacteria maintained their ability to prey on MDR bacteria regardless of their antimicrobial resistance, hence, might be used as therapeutic agents where other antimicrobial drugs fail.

Kadouri, Daniel E.; To, Kevin; Shanks, Robert M. Q.; Doi, Yohei

2013-01-01

204

Prevalence and survival of potential pathogens in source-segregated green waste compost.  

PubMed

Composting of source-separated green waste (SSGW) is essential to meet the EU Landfill Directive target and agricultural land is considered a significant market for the resulting composts. A critical review of the literature was performed to evaluate the potential for pathogens to enter the composting process via SSGW feedstocks and the likelihood of their survival of the composting process and subsequent application to land. This is discussed in the context of application of other organic wastes to land. It was concluded that zoonoses such as verotoxigenic Escherichia coli and Salmonella spp. are unlikely to survive and effective composting process, whereas spore forming organisms are more resistant to composting but are also ubiquitous in the environment. Adherence to existing guidelines, such as those for farm yard manures, is likely to provide a rational degree of health protection for humans and livestock. PMID:22677624

Avery, Lisa M; Booth, Philippa; Campbell, Colin; Tompkins, David; Hough, Rupert L

2012-06-05

205

Potential relationship between Helicobacter pylori and ischemic heart disease: any pathogenic model?  

PubMed

Helicobacter pylori (H.pylori), causal agent of several gastroduodenal diseases, has been involved in diverse aspects of many extragastric manifestations, including ischemic heart disease (IHD). The present paper focuses on the potential pathogenic mechanisms relating H. pylori to IHD. Since H. pylori DNA has been detected in the coronary arteries only in sporadic occasions, and considering that long-term inflammation might raise cytokine levels in the bloodstream, an indirect pathway is more plausible. Moreover, the evidence that some strains of H. pylori induce platelet aggregation supports a role in the acute phase of IHD. In conclusion, because IHD is a multifactorial disease, it is evident that H. pylori is not the only cause. Thus, the definition of H. pylori or other infectious agents as culprits requires a multidisciplinary approach. PMID:18607339

Berrutti, M; Pellicano, R; Fagoonee, S; Astegiano, M; Smedile, A; Saracco, G; Repici, A; Leone, N; Rizzetto, M

2008-06-01

206

In vitro antibacterial activity of modithromycin, a novel 6,11-bridged bicyclolide, against respiratory pathogens, including macrolide-resistant Gram-positive cocci.  

PubMed

The in vitro activities of modithromycin against Gram-positive and -negative respiratory pathogens, including macrolide-resistant cocci with different resistance mechanisms, were compared with those of other macrolide and ketolide agents. MICs were determined by the broth microdilution method. All 595 test strains used in this study were isolated from Japanese medical facilities. The erm (ribosome methylase) and/or mef (efflux pump) gene, which correlated with resistance to erythromycin as well as clarithromycin and azithromycin, was found in 81.8%, 21.3%, and 23.2% of Streptococcus pneumoniae, Streptococcus pyogenes, and methicillin-susceptible Staphylococcus aureus (MSSA) strains, respectively. Modithromycin showed MIC(90)s of 0.125 ?g/ml against these three cocci, including macrolide-resistant strains. In particular, the MIC of modithromycin against ermB-carrying S. pyogenes was ? 32-fold lower than that of telithromycin. The activities of modithromycin as well as telithromycin were little affected by the presence of mefA or mefE in both streptococci. Against Gram-negative pathogens, modithromycin showed MIC(90)s of 0.5, 8, and 0.031 ?g/ml against Moraxella catarrhalis, Haemophilus influenzae, and Legionella spp., respectively. The MICs of modithromycin against M. catarrhalis and H. influenzae were higher than those of telithromycin and azithromycin. However, modithromycin showed the most potent anti-Legionella activity among the macrolide and ketolide agents tested. These results suggested that the bicyclolide agent modithromycin is a novel class of macrolides with improved antibacterial activity against Gram-positive cocci, including telithromycin-resistant streptococci and intracellular Gram-negative bacteria of the Legionella species. PMID:21220534

Sato, Takafumi; Tateda, Kazuhiro; Kimura, Soichiro; Iwata, Morihiro; Ishii, Yoshikazu; Yamaguchi, Keizo

2011-01-10

207

The Potential for pathogenicity was present in the ancestor of the Ascomycete subphylum Pezizomycotina  

PubMed Central

Background Previous studies in Ascomycetes have shown that the function of gene families of which the size is considerably larger in extant pathogens than in non-pathogens could be related to pathogenicity traits. However, by only comparing gene inventories in extant species, no insights can be gained into the evolutionary process that gave rise to these larger family sizes in pathogens. Moreover, most studies which consider gene families in extant species only tend to explain observed differences in gene family sizes by gains rather than by losses, hereby largely underestimating the impact of gene loss during genome evolution. Results In our study we used a selection of recently published genomes of Ascomycetes to analyze how gene family gains, duplications and losses have affected the origin of pathogenic traits. By analyzing the evolutionary history of gene families we found that most gene families with an enlarged size in pathogens were present in an ancestor common to both pathogens and non-pathogens. The majority of these families were selectively maintained in pathogenic lineages, but disappeared in non-pathogens. Non-pathogen-specific losses largely outnumbered pathogen-specific losses. Conclusions We conclude that most of the proteins for pathogenicity were already present in the ancestor of the Ascomycete lineages we used in our study. Species that did not develop pathogenicity seemed to have reduced their genetic complexity compared to their ancestors. We further show that expansion of gained or already existing families in a species-specific way is important to fine-tune the specificities of the pathogenic host-fungus interaction.

2010-01-01

208

Potentially pathogenic features of heterotrophic plate count bacteria isolated from treated and untreated drinking water.  

PubMed

Heterotrophic plate counts (HPCs) are commonly used to assess the general microbiological quality of drinking water. Drinking water quality specifications worldwide recommend HPC limits from 100 to 500 cfu ml(-1). A number of recent studies revealed evidence that these bacteria may not be as harmless as generally accepted. It appears that immuno-compromised individuals are particularly at risk. This would include the very young and very old patients with diseases such as AIDS and patients on therapy for purposes such as organ transplantation and cancer treatment. In this study, 339 bacterial colonies were isolated at random from selected treated and untreated drinking water in South Africa using routine heterotrophic plate count tests. In a first step to screen for potentially pathogenic properties, 188 (55.5%) of the isolates showed alpha- or beta-haemolysis on human- and horse-blood agar media. Subsequent analysis of the haemolytic isolates for enzymatic properties associated with pathogenicity revealed the presence of chondroitinase in 5.3% of the isolates, coagulase in 16.0%, DNase in 60.6%, elastase in 33.0%, fibrinolysin in 53.7%, gelatinase in 62.2%, hyaluronidase in 21.3%, lecithinase in 47.9%, lipase in 54.8% and proteinase in 64.4%. Fluorescein and pyocyanin were not produced by any of the isolates. Among the haemolytic isolates, 77.7% were resistant to oxacillin 1 microg, 59.6% to penicillin G 2 units, 47.3% to penicillin G 10 units, 54.3% to ampicillin 10 microg and 43.1% to ampicillin 25 microg. Cell culture studies revealed that 96% of haemolytic isolates were cytotoxic to HEp-2 cells, and 98.9% of the 181 cytotoxic isolates adhered to HEp-2 or Caco-2 cells. HEp-2 cells were invaded by 43.6%, and Caco-2 cells by 49.7%, of the 181 cytotoxic isolates. The invasion index on HEp-2 cells ranged from 1.9 x 10(-1) to 8.9 x 10(-6), whereas the invasion index on Caco-2 cells varied between 7.7 x 10(-2) and 8.3 x 10(-6). The most commonly isolated genera with these potentially pathogenic features were Aeromonas, Acinetobacter, Aureobacterium, Bacillus, Chryseobacterium, Corynebacterium, Klebsiella, Moraxella, Pseudomonas, Staphylococcus, Tsukamurella and Vibrio. The results obtained in this study support earlier findings on potentially pathogenic features of bacteria detected by routine HPCs on drinking water. These findings are in agreement with some epidemiological studies, which indicated an association between HPCs in drinking water and the incidence of gastroenteritis in consumers. However, the extent of the health risk concerned needs to be defined in more detail for meaningful revision of quality guidelines for HPCs in drinking water. PMID:15145586

Pavlov, D; de Wet, C M E; Grabow, W O K; Ehlers, M M

2004-05-01

209

The potential for respiratory droplet transmissible A/H5N1 influenza virus to evolve in a mammalian host  

PubMed Central

Avian A/H5N1 influenza viruses pose a pandemic threat. As few as five amino acid substitutions, or four with reassortment, might be sufficient for mammal-to-mammal transmission by respiratory droplets. From surveillance data we find that two of these substitutions are common in A/H5N1 viruses and thus some viruses might require only three additional substitutions to become transmissible via respiratory droplets between mammals. We use a mathematical model of within-host virus evolution to study factors that could increase and decrease the probability of the remaining substitutions evolving after the virus has infected a mammalian host. These factors combined with the presence of some of these substitutions in circulating strains, make a virus evolving in nature a potentially serious threat. These results highlight critical areas where more data are needed for assessing, and potentially averting, this threat.

Russell, Colin A.; Fonville, Judith M.; Brown, Andre E. X.; Burke, David F.; Smith, David L.; James, Sarah L.; Herfst, Sander; van Boheemen, Sander; Linster, Martin; Schrauwen, Eefje J.; Katzelnick, Leah; Mosterin, Ana; Kuiken, Thijs; Maher, Eileen; Neumann, Gabriele; Osterhaus, Albert D. M. E.; Kawaoka, Yoshihiro; Fouchier, Ron A. M.; Smith, Derek J.

2012-01-01

210

Production of prodigiosin and chitinases by tropical Serratia marcescens strains with potential to control plant pathogens.  

PubMed

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 ?g/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 ?g/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. PMID:22806790

Gutiérrez-Román, Martha Ingrid; Holguín-Meléndez, Francisco; Bello-Mendoza, Ricardo; Guillén-Navarro, Karina; Dunn, Michael F; Huerta-Palacios, Graciela

2011-06-14

211

?-Amylase is a potential growth inhibitor of Porphyromonas gingivalis, a periodontal pathogenic bacterium.  

PubMed

BACKGROUND AND OBJECTIVE: Porphyromonas gingivalis is a major etiological agent in the development and progression of periodontal diseases. In this study, we isolated a cell growth inhibitor against P. gingivalis species from rice protein extract. MATERIAL AND METHODS: The cell growth inhibitor active against P. gingivalis was purified from polished rice extract using a six-step column chromatography process. Its antimicrobial properties were investigated through microscope analysis, spectrum of activity and general structure. RESULTS: The inhibitor was identified as AmyI-1, an ?-amylase, and showed significant cell growth inhibitory activity against P. gingivalis species. Scanning electron microscopy micrograph analysis and bactericidal assay indicated an intriguing possibility that the inhibitor compromises the cell membrane structure of the bacterial cells and leads to cell death. Moreover, ?-amylases from human saliva and porcine pancreas showed inhibitory activity similar to that of AmyI-1. CONCLUSIONS: This is the first study to report that ?-amylases cause cell death of periodontal pathogenic bacteria. This finding highlights the potential importance and therapeutic potential of ?-amylases in treating periodontal diseases. PMID:23550921

Ochiai, A; Harada, K; Hashimoto, K; Shibata, K; Ishiyama, Y; Mitsui, T; Tanaka, T; Taniguchi, M

2013-04-01

212

Cross-infection potential of crown rot pathogen ( Lasiodiplodia theobromae ) isolates and their management using potential native bioagents in banana  

Microsoft Academic Search

Crown rot infected banana samples collected from different regions of India revealed that the fungus Lasiodiplodia theobromae was the major pathogen responsible for crown rot and Colletotrichum musae and Fusarium spp. were the minor pathogens. The cross-inoculation experiment, conducted using five different virulent isolates of L. theobromae on five different commercial cultivars of banana, demonstrated that generally the isolates were

R. Thangavelu; G. Sangeetha; M. M. Mustaffa

2007-01-01

213

Elafin (elastase-specific inhibitor) has anti-microbial activity against Gram-positive and Gram-negative respiratory pathogens  

Microsoft Academic Search

Elafin (elastase-specific inhibitor) is a low molecular weight inhibitor of neutrophil elastase which is secreted in the lung. Using synthetic peptides corresponding to full-length elafin (H2N-1AVT.....95Q-OH), the NH2-terminal domain (H2N-1AVT.....50K-OH) and the COOH-terminal domain (H2N-51PGS.....95Q-OH), we demonstrate that elafin’s anti-elastase activity resides exclusively in the COOH-terminus. Several characteristics of elafin suggest potential anti-microbial activity. The anti-microbial activity of elafin, and

A. J. Simpson; A. I. Maxwell; J. R. W. Govan; C. Haslett; J.-M. Sallenave

1999-01-01

214

Broadband Respiratory Virus Surveillance.  

National Technical Information Service (NTIS)

Prompt directed therapy of respiratory infections based on pathogen identification is critical for optimizing patient outcomes. This project aims to develop proactive surveillance systems which recognize disease emergence at the earliest possible stage ut...

C. Uyehara S. Stewart

2011-01-01

215

A highly pathogenic porcine reproductive and respiratory syndrome virus generated from an infectious cDNA clone retains the in vivo virulence and transmissibility properties of the parental virus  

Microsoft Academic Search

The nucleotide sequence of a highly pathogenic porcine reproductive and respiratory syndrome virus (PRRSV) was determined. Transfection of MARC-145 cells with capped in vitro transcripts derived from a full-length cDNA clone of the viral genome resulted in infectious PRRSV with growth characteristics similar to that of the parental virus. Primer extension analysis revealed that during replication, the viral polymerase corrected

Ha M Truong; Z Lu; Gerald F Kutish; Judith Galeota; Fernando A Osorio; Asit K Pattnaik

2004-01-01

216

Indirect flight of an African bat to Israel: an example of the potential for zoonotic pathogens to move between continents.  

PubMed

The transmission of harmful pathogens during commercial air flights is an increasing health concern. A potential, yet relatively overlooked source of zoonotic infectious diseases involves collisions of birds and bats with aircraft and long distance transport of their carcasses. We report a case of aerial transportation of the remains of an African fruit bat over three continents, following a collision with an aircraft, and demonstrate the relative ease with which zoonotic pathogens, such as rabies virus or other viruses associated with bats, may cross national boundaries and continents even. Improper handling and disposal of animal remains by airport personnel, may lead to exposure of both humans and local fauna to exotic pathogens. This in turn may trigger an epidemic with potentially devastating results. PMID:17187568

Leader, Noam; Mokady, Ofer; Yom-Tov, Yoram

2006-01-01

217

Experimental Study to Determine if Low-Pathogenicity and High-Pathogenicity Avian Influenza Viruses Can Be Present in Chicken Breast and Thigh Meat Following Intranasal Virus Inoculation  

Microsoft Academic Search

SUMMARY. Two low-pathogenicity (LP) and two high-pathogenicity (HP) avian influenza (AI) viruses were inoculated into chickens by the intranasal route to determine the presence of the AI virus in breast and thigh meat as well as any potential role that meat could fill as a transmission vehicle. The LPAI viruses caused localized virus infections in respiratory and gastrointestinal (GI) tracts.

David E. Swayne; Joan R. Beck

2005-01-01

218

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

Microsoft Academic Search

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

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

2009-01-01

219

Genome Sequence of Aureobasidium pullulans AY4, an Emerging Opportunistic Fungal Pathogen with Diverse Biotechnological Potential  

PubMed Central

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.

Bamadhaj, Hasima Mustafa; Gan, Han Ming; Rashid, Noor Aini Abdul

2012-01-01

220

Chronic laminitis is associated with potential bacterial pathogens in the laminae.  

PubMed

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. PMID:22410310

Onishi, Janet C; Park, Joong-Wook; Häggblom, Max M; Fennell, Michael J; Fugaro, Michael N

2012-02-21

221

New insights concerning the occurrence of fungi in water sources and their potential pathogenicity.  

PubMed

Fungi are known to occur ubiquitously in the environment. In the past years, the occurrence of filamentous fungi in the aquatic environment has been a subject of growing interest. This study describes the occurrence of various fungal genera in different drinking water sources being Penicillium and Trichoderma the most representative ones (30% and 17%, respectively). Also, 24 fungal species that have not been previously described in the aquatic environment are reported in this study, being once again the major species from the Penicillium genera. This study therefore contributes to the knowledge on the richness of fungi diversity in water. 68% of the described species were found to be able to grow at 30 °C but only Aspergillus fumigatus, Aspergillus viridinutans and Cunninghamella bertholletiae were able to grow at the higher temperature tested (42 °C). 66% of the species that were able to grow at 30 °C have spore sizes below 5 ?m which enables them to cause breathing infections. These were therefore identified as potential pathogenic species. PMID:24011405

Oliveira, B R; Barreto Crespo, M T; San Romão, M V; Benoliel, M J; Samson, R A; Pereira, V J

2013-08-15

222

Ribotypes and virulence gene polymorphisms suggest three distinct Listeria monocytogenes lineages with differences in pathogenic potential.  

PubMed Central

A total of 133 Listeria monocytogenes isolates were characterized by ribotyping and allelic analysis of the virulence genes hly, actA, and inlA to uncover linkages between independent phylogenetic and specific virulence markers. PCR-restriction fragment length polymorphisms revealed 8 hly, 11 inl4, and 2 actA alleles. The combination of these virulence gene alleles and ribotype patterns separated L. monocytogenes into three distinct lineages. While distinct hly and inlA alleles were generally found to cluster into these three lineages, actA alleles segregated independently. These three phylogenetic lineages were confirmed when 22 partial actA DNA sequences were analyzed. The clinical history of the L. monocytogenes strains showed evidence for differences in pathogenic potential among the three lineages. Lineage I contains all strains isolated during epidemic outbreaks of listeriosis, while no human isolates were found in lineage III. Animal isolates were found in all three lineages. We found evidence that isolates from lineages I and III have a higher plaquing efficiency than lineage II strains in a cell culture assay. Strains from lineage III also seem to form larger plaques than strains from lineage II. A distinctive ribotype fragment and unique 16S rRNA gene sequences furthermore suggest that lineage III might represent a L. monocytogenes subspecies. None of the 20 human isolates available but 11% of our animal isolates were grouped in this lineage, indicating that strains in this lineage might have reduced virulence for humans.

Wiedmann, M; Bruce, J L; Keating, C; Johnson, A E; McDonough, P L; Batt, C A

1997-01-01

223

Years of potential life lost for six major enteric pathogens, Germany, 2004-2008.  

PubMed

In industrialized countries, acute infectious enteric diseases are usually mild, but they can also cause death. They do so, however, at different ages. Using 2004-2008 German notification data, we computed and compared crude and premature mortality [three different measures of years of potential life lost (YPLL)] of illnesses caused by Campylobacter spp., Listeria monocytogenes, norovirus, rotavirus, non-typhoidal Salmonella spp., and Shiga toxin-producing E. coli (STEC). Among ~1.5 million notified illnesses, those caused by norovirus were the most frequent. The highest annual mortality was registered for salmonellosis (0.55/1 000 000 population), but listeriosis accounted for the highest number of YPLL (n=4245). Disregarding death at advanced age (i.e. >70 years), STEC illness (n=757) and rotavirus gastroenteritis (n=648) ranked second and third, following listeriosis (n=2306). Routine surveillance captures only a fraction of all incident cases and deaths, under-ascertaining the true burden of disease. Weighting death by age permits a different view on the disease burden individual enteric pathogens cause and particularly underscores the public health importance of listeriosis prevention. PMID:22813426

Werber, D; Hille, K; Frank, C; Dehnert, M; Altmann, D; Müller-Nordhorn, J; Koch, J; Stark, K

2012-07-20

224

Antimicrobial potential of Ricinus communis leaf extracts in different solvents against pathogenic bacterial and fungal strains  

PubMed Central

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.

Naz, Rabia; Bano, Asghari

2012-01-01

225

Proteomic Analysis of Human Serum for Finding Pathogenic Factors and Potential Biomarkers in Preeclampsia  

PubMed Central

Objective(s) To apply a novel proteomic method to discover potential pathogenic factors and biomarkers of preeclampsia. Study design Sera from five patients complicated with preeclampsia and five healthy pregnant controls were separately pooled. Each pool was treated with peptide ligand library beads (PLLBs) to remove high abundance proteins by affinity and thus enrich low abundance proteins. The proteins from the eluate were analyzed by a combination of 1D-Gel-LC-MS/MS. Protein expression levels were quantified using spectral counts and the extracted ion current. Results 1172 unique proteins in preeclampsia and 1149 in healthy controls were identified in the present study. 51 proteins were differentially expressed between preeclampsia and healthy pregnant women including chorionic somatommammptropin hormone (CSH) and fibulin-1. 31 proteins identified were up-regulated and 20 were down-regulated. Conclusions The results demonstrate that peptide ligand library combining with 1D gel-LC-MS/MS analysis is an efficient method to identify differentially expressed proteins in sera and two biological processes of complement and coagulation activations and lipid metabolism were involved in the pathogenesis of preeclampsia.

Liu, Chongdong; Zhang, Nawei; Yu, Haiqiang; Chen, Yuxuan; Liang, Yong; Deng, Haiteng; Zhang, Zhenyu

2010-01-01

226

Adaptive potential of ash (Fraxinus excelsior) populations against the novel emerging pathogen Hymenoscyphus pseudoalbidus  

PubMed Central

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.

Kjaer, Erik Dahl; McKinney, Lea Vig; Nielsen, Lene Rostgaard; Hansen, Lars N?rgaard; Hansen, Jon Kehlet

2012-01-01

227

Antibacterial potential of silver nanoparticles against isolated urinary tract infectious bacterial pathogens  

NASA Astrophysics Data System (ADS)

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 ?g 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.

Jacob Inbaneson, Samuel; Ravikumar, Sundaram; Manikandan, Nachiappan

2011-12-01

228

Using mixture design to construct consortia of potential probiotic Bacillus strains to protect gnotobiotic Artemia against pathogenic Vibrio  

Microsoft Academic Search

To evaluate the potential probiotic effect of three Bacillus strains on the survival and growth of an Artemia culture and to obtain the optimal formulation of pure cultures of the bacilli, challenge tests were performed with the pathogenic bacterium Vibrio alginolyticus (S1) using mixture design. According to molecular analyses involving amplified ribosomal DNA restriction analysis (ARDRA), these bacteria corresponded to

Abdelkarim Mahdhi; Besma Harbi; Maria Ángeles Esteban; Kamel Chaieb; Fathi Kamoun; Amina Bakhrouf

2010-01-01

229

Interaction of cellular poly(C)-binding protein 2 with nonstructural protein 1? is beneficial to Chinese highly pathogenic porcine reproductive and respiratory syndrome virus replication.  

PubMed

Non-structural protein1? (Nsp1?) of porcine reproductive and respiratory syndrome virus (PRRSV) has been recognized to be involved in suppressing the host innate immune response and mediating viral subgenomic mRNA transcription. In the present study, we have analyzed the interaction of Nsp1? of Chinese highly pathogenic PRRSV (HP-PRRSV) with cellular poly(C)-binding 2 (PCBP2) by means of the yeast two-hybrid screening in a pulmonary alveolar macrophages (PAMs) cDNA library and co-immunoprecipitation (Co-IP) assay. Our results indicated that the Nsp1? of the HP-PRRSV is able to bind and interact with cellular PCBP2 strongly in both the infected cells and plasmid transfected cells. Their minimal binding regions were identified to be the residues 85-203 aa (PCP? and CTE domains) for the Nsp1? and the residues 96-168 aa (KH2 domain) for PCBP2, respectively. Next, we used confocal immunofluorescence analysis and discovered that, during PRRSV infection in MARC-145 cells and/or plasmid-transfected cells, the Nsp1? and PCBP2 mainly colocalized in the cytoplasm and perinuclear pattern. Moreover, the siRNA-mediated silencing of PCBP2 gene in the MARC-145 cells resulted in significant reduction of the virus titer in supernatants as well as viral proteins, while no significant effects on the expression of the type I interferon ? and interferon ?, suggesting that the interaction of the Nsp1? with cellular PCBP2 is beneficial to Chinese HP-PRRSV replication in MARC-145 cells. PMID:22951310

Wang, Lin; He, Qing; Gao, Yueyi; Guo, Xin; Ge, Xinna; Zhou, Lei; Yang, Hanchun

2012-08-20

230

The CRP/FNR family protein Bcam1349 is a c-di-GMP effector that regulates biofilm formation in the respiratory pathogen Burkholderia cenocepacia.  

PubMed

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. PMID:21883527

Fazli, Mustafa; O'Connell, Aileen; Nilsson, Martin; Niehaus, Karsten; Dow, J Maxwell; Givskov, Michael; Ryan, Robert P; Tolker-Nielsen, Tim

2011-09-07

231

Characterization of Stg Fimbriae from an Avian Pathogenic Escherichia coli O78:K80 Strain and Assessment of Their Contribution to Colonization of the Chicken Respiratory Tract  

PubMed Central

In a previous study, ecs-3, a sequence from avian pathogenic Escherichia coli (APEC) O78:K80 strain ?7122, was found to be expressed in vivo in infected chicken tissues. The region encompassing ecs-3 carries a fimbrial gene cluster that is a putative ortholog of the stg fimbrial gene cluster of Salmonella enterica serovar Typhi. This APEC fimbrial gene cluster, which we have termed stg, is a member of a distinct group of related fimbriae that are located in the glmS-pstS intergenic region of certain E. coli and S. enterica strains. Under the control of the pBAD promoter, the production of Stg fimbriae was demonstrated by Western blotting and immunogold electron microscopy with E. coli K-12. Transcriptional fusions suggest that stg expression is influenced by the carbohydrate source and decreased by the addition of iron and that Fur plays a role in the regulation of stg expression. stg sequences were associated with APEC O78 isolates, and stg was phylogenetically distributed among E. coli reference strains and clinical isolates from human urinary tract infections. Stg fimbriae contributed to the adherence of a nonfimbriated E. coli K-12 strain to avian lung sections and human epithelial cells in vitro. Coinfection experiments with APEC strain ?7122 and an isogenic ?stg mutant demonstrated that compared to the wild-type parent, the ?stg mutant was less able to colonize air sacs, equally able to colonize lungs, and able to more effectively colonize tracheas of infected chickens. Stg fimbriae, together with other adhesins, may therefore contribute to the colonization of avian respiratory tissues by certain APEC strains.

Lymberopoulos, Maria H.; Houle, Sebastien; Daigle, France; Leveille, Simon; Bree, Annie; Moulin-Schouleur, Maryvonne; Johnson, James R.; Dozois, Charles M.

2006-01-01

232

Advances in and the potential of vaccines for respiratory syncytial virus.  

PubMed

Respiratory syncytial virus (RSV) is the leading cause of serious lower respiratory track illness causing bronchiolitis and some mortality in infants and the elderly. Despite decades of research there is no licensed RSV vaccine. To enable the development of RSV vaccines, several major obstacles must be overcome including immature and waning immunity to RSV infection, the capacity of RSV to evade immunity and the failure of RSV infection to induce robust enduring immunity. Since the failure of the formalin-inactivated RSV vaccine trial, more cautious and deliberate progress has been made toward RSV vaccine development using a variety of experimental approaches. The scientific rational and the state of development of these approaches are reviewed in this article. PMID:23964629

Jorquera, Patricia A; Oakley, Katie E; Tripp, Ralph A

2013-08-01

233

Distinctive Expansion of Potential Virulence Genes in the Genome of the Oomycete Fish Pathogen Saprolegnia parasitica  

PubMed Central

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.

Belmonte, Rodrigo; Lobach, Lars; Christie, James; van den Ackerveken, Guido; Bottin, Arnaud; Bulone, Vincent; Diaz-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

234

Reptiles as potential vectors and hosts of the amphibian pathogen Batrachochytrium dendrobatidis in Panama.  

PubMed

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. PMID:22303629

Kilburn, Vanessa L; Ibáñez, Roberto; Green, David M

2011-12-01

235

Isolation and characterization of highly pathogenic avian influenza virus subtype H5N1 from donkeys  

Microsoft Academic Search

BACKGROUND: The highly pathogenic H5N1 is a major avian pathogen that crosses species barriers and seriously affects humans as well as some mammals. It mutates in an intensified manner and is considered a potential candidate for the possible next pandemic with all the catastrophic consequences. METHODS: Nasal swabs were collected from donkeys suffered from respiratory distress. The virus was isolated

Ahmed S Abdel-Moneim; Ahmad E Abdel-Ghany; Salama AS Shany

2010-01-01

236

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

NASA Astrophysics Data System (ADS)

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.

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

1999-12-01

237

Variable pathogenic potentials of mutations located in the desmin alpha-helical domain  

Microsoft Academic Search

Mutations in the desmin gene have been recognized as a cause of desminopathy, a familial or sporadic disorder characterized by skeletal muscle weakness, often associated with cardiomyopathy or respiratory insufficiency. Distinctive histopathologic features include aberrant intracytoplasmic accumulation of desmin (DES). We present here comparative phenotypic, molecular, and functional characteristics of four novel and three previously reported, but not fully characterized,

Bertrand Goudeau; Fernando Rodrigues-Lima; Dirk Fischer; Monique Casteras-Simon; Nyamkhishig Sambuughin; Marianne de Visser; Pascal Laforet; Xavier Ferrer; Françoise Chapon; G. Sjoberg; Anna Kostareva; Thomas Sejersen; Marinos C. Dalakas; Lev G. Goldfarb; Patrick Vicart

2006-01-01

238

A Comparative Study of Metabolic Network Topology between a Pathogenic and a Non-Pathogenic Bacterium for Potential Drug Target Identification  

PubMed Central

Metabolic network provides a unified platform to integrate all the biological information on genes, proteins, metabolites, drugs and drug targets for a comprehensive system level study of the relationship between metabolism and disease. In recent times, drug-target identification by in silico methods has emerged causing a phenomenal achievement in the field of drug discovery. This paper focuses on describing how microbial drug target identification can be carried out using bioinformatic tools. Specifically, it highlights the use of metabolic ‘choke point’ and ‘load point’ analyses to understand the local and global properties of metabolic networks in Pseudomonas aeruginosa and allow us to identify potential drug targets. We also list out top 10 choke point enzymes based on the load point values and the number of shortest paths. A non-pathogenic bacterial strain Pseudomonas putida KT2440 and a related pathogenic bacteria P.aeruginosa PA01 was selected for the network anlaysis. A comparative study of the metabolic networks of these two microbes highlights the analogies and differences between their respective pathways. System analysis of metabolic networks will help us in identifying new drug targets which in turn will generate more in-depth understanding of the mechanism of diseases and thus provide better guidance for drug discovery.

Perumal, Deepak; Lim, Chu Sing; Sakharkar, Meena K.

2009-01-01

239

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

PubMed

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. PMID:3998880

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

1985-04-01

240

Potential risks to human respiratory health from "acid fog": evidence from experimental studies of volunteers.  

PubMed

Observations of high acidity (pH as low as 1.7) in fogwater collected in polluted areas have provoked concern for public health. Effects of exposure to acidic pollutants have not been studied under foggy conditions; thus there is no directly relevant information from which to estimate the health risk. Indirectly relevant information is available from numerous studies of volunteers exposed to "acid fog precursors" under controlled conditions at less than 100% relative humidity. The effect of fog in modifying responses to inhaled acidic pollutants is difficult to predict: depending on circumstances, fog droplets might either increase or decrease the effective dose of pollutants to the lower respiratory tract. Fog inhalation per se may have unfavorable effects in some individuals. Sulfur dioxide is known to exacerbate airway constriction in exercising asthmatics, at exposure concentrations attainable in ambient air. Nitrogen dioxide has shown little untoward respiratory effect at ambient concentrations in most studies, although it has been suggested to increase bronchial reactivity. Sulfuric acid aerosol has shown no clear effects at concentrations within the ambient range. At somewhat higher levels, increased bronchial reactivity and change in mucociliary clearance have been suggested. Almost no information is available concerning nitric acid. PMID:3000761

Hackney, J D; Linn, W S; Avol, E L

1985-11-01

241

Potential risks to human respiratory health from "acid fog": evidence from experimental studies of volunteers.  

PubMed Central

Observations of high acidity (pH as low as 1.7) in fogwater collected in polluted areas have provoked concern for public health. Effects of exposure to acidic pollutants have not been studied under foggy conditions; thus there is no directly relevant information from which to estimate the health risk. Indirectly relevant information is available from numerous studies of volunteers exposed to "acid fog precursors" under controlled conditions at less than 100% relative humidity. The effect of fog in modifying responses to inhaled acidic pollutants is difficult to predict: depending on circumstances, fog droplets might either increase or decrease the effective dose of pollutants to the lower respiratory tract. Fog inhalation per se may have unfavorable effects in some individuals. Sulfur dioxide is known to exacerbate airway constriction in exercising asthmatics, at exposure concentrations attainable in ambient air. Nitrogen dioxide has shown little untoward respiratory effect at ambient concentrations in most studies, although it has been suggested to increase bronchial reactivity. Sulfuric acid aerosol has shown no clear effects at concentrations within the ambient range. At somewhat higher levels, increased bronchial reactivity and change in mucociliary clearance have been suggested. Almost no information is available concerning nitric acid.

Hackney, J D; Linn, W S; Avol, E L

1985-01-01

242

Antimicrobial Resistance among Respiratory Pathogens in Spain: Latest Data and Changes over 11 Years (1996-1997 to 2006-2007)?  

PubMed Central

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 ?g/ml. In S. pyogenes, nonsusceptibility to erythromycin was observed in 19.4% of isolates. Among the H. influenzae isolates, a ?-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%), ?-lactamase production (from 25.7% to 15.7%), and ?-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.

Perez-Trallero, Emilio; Martin-Herrero, Jose E.; Mazon, Ana; Garcia-Delafuente, Celia; Robles, Purificacion; Iriarte, Victor; Dal-Re, Rafael; Garcia-de-Lomas, Juan

2010-01-01

243

Ralstonia solanacearum Strains from Martinique (French West Indies) Exhibiting a New Pathogenic Potential? †  

PubMed Central

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.

Wicker, Emmanuel; Grassart, Laurence; Coranson-Beaudu, Regine; Mian, Daniele; Guilbaud, Caroline; Fegan, Mark; Prior, Philippe

2007-01-01

244

Evaluation of the Antibacterial Potential of Some Plants Against Human Pathogenic Bacteria  

Microsoft Academic Search

Plants are rich source of antibacterial agents, which could be exploited in human disease management. Aqueous extracts of leaves of 46 plants selected based on an ethnobotanical survey from Mysore region Karnataka (India) were subjected to in vitro antibacterial activity assay against 14 important human pathogenic bacteria employing cup diffusion method. Antibacterial activity of the twelve plants aqueous extracts was

S. Satish; M. P. Raghavendra; K. A. Raveesha

245

Bacterial diversity in a marine hatchery: Balance between pathogenic and potentially probiotic bacterial strains  

Microsoft Academic Search

Aquatic hatcheries contain diverse microbial communities that include pathogenic, innocuous and beneficial bacteria, and the ability to maintain a proper balance of this microflora may be the key to a successful culture environment. Herein, we undertook to identify the bacterial diversity present in a marine hatchery in British Columbia that cultures both fish and shellfish species. Bacterial strains were cultured

Angela D. Schulze; Abayomi O. Alabi; Adele R. Tattersall-Sheldrake; Kristina M. Miller

2006-01-01

246

Contemporary Testing for Enteric Pathogens: the Potential for Cost, Time, and Health Care Savings  

Microsoft Academic Search

We sent a questionnaire to 79 clinical microbiology laboratories seeking information on contemporary practices when investigating for bacterial and protozoan enteric pathogens. Data from the 67 respondents (response rate of 85%) showed that a minority of laboratories (40% for stool culture and 45% for ova and parasite (O&P) examinations) had restrictions for testing in place and that fewer laboratories (24%

ARTHUR J. MORRIS; PATRICK R. MURRAY; BARTH RELLER

1996-01-01

247

Disease induction by human microbial pathogens in plant-model systems: potential, problems and prospects  

Microsoft Academic Search

Relatively simple eukaryotic model organisms such as the genetic model weed plant Arabidopsis thaliana possess an innate immune system that shares important similarities with its mammalian counterpart. In fact, some human pathogens infect Arabidopsis and cause overt disease with human symptomology. In such cases, decisive elements of the plant's immune system are likely to be targeted by the same microbial

Peter van Baarlen; Alex van Belkum; Bart P. H. J. Thomma

2007-01-01

248

Rhizoctonia Resistant Wheat -- Potential New Resources for Control for Soilborne Pathogens.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Pacific Northwest (PNW) wheat, barley, legume and canola varieties are susceptible to the broad host-range soilborne pathogens that cause Rhizoctonia root rot and Pythium root rot. Effective control of these diseases will likely require additional approaches and resources. We have identified promisi...

249

In Vitro Antimicrobial Potential of the Lichen Parmotrema sp. Extracts against Various Pathogens  

PubMed Central

Objective(s): The ongoing increasing antibiotic resistance is one of the biggest challenges faced by global public health. The perennial need for new antimicrobials against a background of increasing antibiotic resistance in pathogenic and opportunistic microorganisms obliges the scientific community to constantly develop new drugs and antimicrobial agents. Lichens are known prolific sources of natural antimicrobial drugs and biologically active natural products. This study was aimed to explore in vitro antimicrobial activity of lichen Parmotrema sp. Material and Methods: The methanol and aqueous extracts of lichen Parmotrema sp. was extracted using Soxhlet extractor. Antibiotic assessment of methanol and aqueous extracts was done against eight bacterial (Escherichia coli, Staphylococcus aureus, Proteus mirabilis, Salmonella sp., Shigella sp., Enterococci faecalis, Pseudomonas aeruginosa, Klebsiella pneumoniae,) clinical pathogens and five plant pathogenic fungal strains (Aspergillus terreus strain JAS1, Scedosporium sp. JAS1, Ganoderma sp. JAS4, Candida tropicalis and Fusarium sp.) by Kirby-Bauer method. Results: The methanol lichen Parmotrema sp. extract inhibited all the test organisms. The highest antibacterial activity was found against Pseudomonas aeruginosa and Staphylococcus aureus. The weakest activity was manifested in Salmonella sp. and Scedosporium sp. JAS1. Strong antifungal effect was found against Ganoderma sp. JAS4 and Fusarium sp. The aqueous lichen Parmotrema sp. extract revealed neither antibacterial nor antifungal activity. Conclusion: The present study shows that tested lichen Parmotrema sp. extracts demonstrated a strong antimicrobial effect. That suggests the active components from methanol extracts of the investigated lichen Parmotrema sp. can be used as natural antimicrobial agent against pathogens.

Chauhan, Ritika; Abraham, Jayanthi

2013-01-01

250

In Vitro Antimicrobial Potential of the Lichen Parmotrema sp. Extracts against Various Pathogens.  

PubMed

Objective(s): The ongoing increasing antibiotic resistance is one of the biggest challenges faced by global public health. The perennial need for new antimicrobials against a background of increasing antibiotic resistance in pathogenic and opportunistic microorganisms obliges the scientific community to constantly develop new drugs and antimicrobial agents. Lichens are known prolific sources of natural antimicrobial drugs and biologically active natural products. This study was aimed to explore in vitro antimicrobial activity of lichen Parmotrema sp. Material and Methods: The methanol and aqueous extracts of lichen Parmotrema sp. was extracted using Soxhlet extractor. Antibiotic assessment of methanol and aqueous extracts was done against eight bacterial (Escherichia coli, Staphylococcus aureus, Proteus mirabilis, Salmonella sp., Shigella sp., Enterococci faecalis, Pseudomonas aeruginosa, Klebsiella pneumoniae,) clinical pathogens and five plant pathogenic fungal strains (Aspergillus terreus strain JAS1, Scedosporium sp. JAS1, Ganoderma sp. JAS4, Candida tropicalis and Fusarium sp.) by Kirby-Bauer method. Results: The methanol lichen Parmotrema sp. extract inhibited all the test organisms. The highest antibacterial activity was found against Pseudomonas aeruginosa and Staphylococcus aureus. The weakest activity was manifested in Salmonella sp. and Scedosporium sp. JAS1. Strong antifungal effect was found against Ganoderma sp. JAS4 and Fusarium sp. The aqueous lichen Parmotrema sp. extract revealed neither antibacterial nor antifungal activity. Conclusion: The present study shows that tested lichen Parmotrema sp. extracts demonstrated a strong antimicrobial effect. That suggests the active components from methanol extracts of the investigated lichen Parmotrema sp. can be used as natural antimicrobial agent against pathogens. PMID:23997920

Chauhan, Ritika; Abraham, Jayanthi

2013-07-01

251

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...

252

Lipidome analysis in multiple sclerosis reveals protein lipoxidative damage as a potential pathogenic mechanism.  

PubMed

Metabolomic and lipidomic analyses have been used for the profiling of neurodegenerative processes, both in targeted and untargeted approaches. In this work we have applied these techniques to the study of CSF samples of multiple sclerosis (MS) patients (n = 9), compared with samples of non-MS individuals (n = 9) using mass-spectrometry. We have used western-blot and analyzed cell culture to confirm pathogenic pathways suggested by mass-spectrometric measurements. The results of the untargeted approach of metabolomics and lipidomics suggest the existence of several metabolites and lipids discriminating both populations. Applying targeted lipidomic analyses focused to a pathogenic pathway in MS, oxidative stress, reveal that the lipid peroxidation marker 8-iso-prostaglandin F2? is increased in CSF from MS patients. Furthermore, as lipid peroxidation exerts its pathogenical effects through protein modification, we studied the incidence of protein lipoxidation, revealing specific increases in carboxymethylated, neuroketal and malondialdehyde-mediated protein modifications in proteins of CSF from MS patients, despite the absence of their precursors glyoxal and methylglyoxal. Finally, we report that the level of neuroketal-modified proteins correlated with a hitherto unknown increased amount of autoantibodies against lipid peroxidation-modified proteins in CSF, without compensation by signaling induced by lipid peroxidation via peroxisome proliferator-activated receptor ? (PPAR?). The results, despite the limitation of being obtained in a small population, strongly suggest that autoimmunity against in situ produced epitopes derived from lipid peroxidation can be a relevant pathogenic factor in MS. PMID:22924648

Gonzalo, Hugo; Brieva, Luis; Tatzber, Franz; Jové, Mariona; Cacabelos, Daniel; Cassanyé, Anna; Lanau-Angulo, Lucia; Boada, Jordi; Serrano, José C E; González, Cristina; Hernández, Lourdes; Peralta, Sílvia; Pamplona, Reinald; Portero-Otin, Manuel

2012-09-28

253

Potentiation of pathogen-specific defense mechanisms in Arabidopsis by -aminobutyric acid  

Microsoft Academic Search

The nonprotein amino acids -aminobutyric acid (GABA) and -aminobutyric acid (BABA) have known biological effects in animals and plants. Their mode of action has been the object of thorough research in animals but remains unclear in plants. Our objective was to study the mode of action of BABA in the protection of Arabidopis plants against virulent pathogens. BABA protected Arabidopsis

Laurent Zimmerli; Gabor Jakab; Jean-Pierre Métraux; Brigitte Mauch-Mani

2000-01-01

254

The bryophyte genus Sphagnum is a reservoir for powerful and extraordinary antagonists and potentially facultative human pathogens.  

PubMed

Sphagnum plants grow in natural, species-poor carpets at low pH but without any known substantial fungal disease. To investigate this phenomenon, we analysed bacterial populations associated with two Sphagnum species with different ecological behaviour, namely S. magellanicum and S. fallax, from three sites in Germany and three in Norway, with a special focus on the functional group of antagonists. The screening of 493 bacterial isolates for antagonistic activity against fungal pathogens resulted in 237 (48%) active isolates. We found a higher proportion of antagonists for S. magellanicum (24%) than we did for S. fallax (19%) in general. The majority of the antagonists belonged to the genera Serratia (15%), Burkholderia (13.5%), Staphylococcus (13.5%), and Pseudomonas (10%). In contrast to the high moss specificity found for antagonistic bacteria, Burkholderia as well as Serratia isolates with highly similar molecular fingerprints as ascertained by BOX-PCR for both Sphagnum species were found. Interestingly, a high proportion of antagonists, for example Staphylococcus, Hafnia, Yersinia, and Pantoea, were identified as strains that are known as facultative pathogens of humans. Sphagnum plants represent an ecological niche not only for diverse and extraordinary microbial populations with a high potential for biological control of plant pathogens but also for opportunistic human pathogens. PMID:17484734

Opelt, Katja; Berg, Christian; Berg, Gabriele

2007-04-30

255

New Respiratory Viruses and the Elderly  

PubMed Central

The diagnostics of respiratory viral infections has improved markedly during the last 15 years with the development of PCR techniques. Since 1997, several new respiratory viruses and their subgroups have been discovered: influenza A viruses H5N1 and H1N1, human metapneumovirus, coronaviruses SARS, NL63 and HKU1, human bocavirus, human rhinoviruses C and D and potential respiratory pathogens, the KI and WU polyomaviruses and the torque teno virus. The detection of previously known viruses has also improved. Currently, a viral cause of respiratory illness is almost exclusively identifiable in children, but in the elderly, the detection rates of a viral etiology are below 40%, and this holds also true for exacerbations of chronic respiratory illnesses. The new viruses cause respiratory symptoms like the common cold, cough, bronchitis, bronchiolitis, exacerbations of asthma and chronic obstructive pulmonary disease and pneumonia. Acute respiratory failure may occur. These viruses are distributed throughout the globe and affect people of all ages. Data regarding these viruses and the elderly are scarce. This review introduces these new viruses and reviews their clinical significance, especially with regard to the elderly population.

Jartti, Laura; Langen, Henriikka; Soderlund-Venermo, Maria; Vuorinen, Tytti; Ruuskanen, Olli; Jartti, Tuomas

2011-01-01

256

A novel in silico approach to identify potential therapeutic targets in human bacterial pathogens  

Microsoft Academic Search

In recent years, genome-sequencing projects of pathogens and humans have revolutionized microbial drug target identification.\\u000a Of the several known genomic strategies, subtractive genomics has been successfully utilized for identifying microbial drug\\u000a targets. The present work demonstrates a novel genomics approach in which codon adaptation index (CAI), a measure used to\\u000a predict the translational efficiency of a gene based on synonymous

Umashankar Vetrivel; Gurunathan Subramanian; Sudarsanam Dorairaj

257

The impact of pesticides on the pathogen Batrachochytrium dendrobatidis independent of potential hosts.  

PubMed

Amphibians around the world are experiencing the greatest organismal decline in recent history. Xenobiotics, such as pesticides, and pathogenic biotic perturbations, including the fungus Batrachochytrium dendrobatidis (Bd), have played major roles in amphibian decreases. We conducted laboratory culture studies to determine the effects of three pesticides {carbaryl, glyphosate, and thiophanate-methyl [TM; Topsin-M(R) (Cerexagri-Nisso LLC)]} on Bd zoospore production and zoosporangia growth. We applied Bd to pesticides mixed in an agar culture to simulate pathogen introduction to a system with pre-existing pesticides (Bd addition). Alternatively, pesticides were applied to pre-established Bd to simulate pesticide introduction after Bd establishment (pesticide addition). We then measured Bd zoosporangia and zoospore production. All pesticides significantly inhibited zoospore production; however, glyphosate and TM were more effective at doing so than carbaryl. In addition, only carbaryl and glyphosate inhibited zoosporangia production. Our data suggest that carbaryl and glyphosate are equally effective at inhibiting both zoosporangia and zoospore production; however, TM is selectively toxic to zoospores but not zoosporangia. One possible explanation for this observation could be that TM is toxic to zoospores but not the protective zoosporangia. In the case of pesticides applied to established Bd cultures, all pesticides caused significant mortality in both zoosporangia and zoospores, and no differences were found among pesticides. We conclude that examining pesticide and pathogen interactions independent of hosts provides mechanistic understanding of such interactions before and after host infection or contamination. PMID:22228138

Hanlon, Shane M; Parris, Matthew J

2012-01-07

258

Coinfection of pigs with Porcine Respiratory Coronavirus and Bordetella bronchisphica  

Technology Transfer Automated Retrieval System (TEKTRAN)

Coinfection with two or more pathogens is a common occurrence in respiratory diseases of most species. The manner in which multiple pathogens interact is not always straightforward, however. Bordetella bronchiseptica and porcine respiratory coronavirus (PRCV) are respiratory pathogens of pigs whos...

259

Inhibition of Airway Na+ Transport by Respiratory Syncytial Virus  

Microsoft Academic Search

In previous studies, we have shown that two major respiratory pathogens, influenza virus and parainfluenza virus, produce acute alterations in ion transport upon contacting the apical membrane of the respiratory epithelium. In the present study, we examine the effects on ion transport by the mouse tracheal epithelium of a third major respiratory pathogen, respiratory syncytial virus (RSV). RSV infections are

Karl Kunzelmann; Jane Sun; Jayesh Meanger; Nicholas J. King; David I. Cook

2007-01-01

260

Chemosensory TRP Channels in the Respiratory Tract: Role in Toxic Lung Injury and Potential as "Sweet Spots" for Targeted Therapies.  

PubMed

Acute toxic lung injury by reactive inhalational compounds is an important and still unresolved medical problem. Hazardous gases or vapors, e. g. chlorine, phosgene, sulfur mustard or methyl isocyanate, are released during occupational accidents or combustion processes and also represent a potential threat in terroristic scenarios. According to their broad-range chemical reactivity, the mechanism of lung injury evoked by these agents has long been described as rather unspecific. Consequently, therapeutic options are still restricted to symptomatic treatment. However, in recent years, ion channels of the transient receptor potential (TRP) family have been identified to act as specific sensor molecules expressed in the respiratory tract and to engage defined signaling pathways upon inhalational exposure to toxic challenges. These pulmonary receptor molecules have been primarily characterized in sensory neurons of the lung. However, chemosensory molecules are also expressed in non-neuronal cells, e.g. in the lung epithelium as well as in the pulmonary vasculature. Thus, activation of respiratory chemosensors by toxic inhalants promotes a complex signaling network directly or indirectly regulating pulmonary blood flow, the integrity of the epithelial lining, and the mucociliary clearance of the bronchial system. This review gives a synopsis on reactive lung-toxic agents and their specific target molecules in the lung and summarizes the current knowledge about the pathophysiological role of chemosensory signaling in neuronal and non-neuronal cells in toxic lung injury. Finally, we describe possible future strategies for a causal, specifically tailored treatment option based on the mechanistic understanding of molecular events ensuing inhalation of lung-toxic agents. PMID:23532495

Büch, Thomas; Schäfer, Eva; Steinritz, Dirk; Dietrich, Alexander; Gudermann, Thomas

2013-01-01

261

Respiratory Health Effects of Airborne Particulate Matter: The Role of Particle Size, Composition, and Oxidative Potential--The RAPTES Project  

PubMed Central

Background: Specific characteristics of particulate matter (PM) responsible for associations with respiratory health observed in epidemiological studies are not well established. High correlations among, and differential measurement errors of, individual components contribute to this uncertainty. Objectives: We investigated which characteristics of PM have the most consistent associations with acute changes in respiratory function in healthy volunteers. Methods: We used a semiexperimental design to accurately assess exposure. We increased exposure contrast and reduced correlations among PM characteristics by exposing volunteers at five different locations: an underground train station, two traffic sites, a farm, and an urban background site. Each of the 31 participants was exposed for 5 hr while exercising intermittently, three to seven times at different locations during March–October 2009. We measured PM10, PM2.5, particle number concentrations (PNC), absorbance, elemental/organic carbon, trace metals, secondary inorganic components, endotoxin content, gaseous pollutants, and PM oxidative potential. Lung function [FEV1 (forced expiratory volume in 1 sec), FVC (forced vital capacity), FEF25–75 (forced expiratory flow at 25–75% of vital capacity), and PEF (peak expiratory flow)] and fractional exhaled nitric oxide (FENO) were measured before and at three time points after exposure. Data were analyzed with mixed linear regression. Results: An interquartile increase in PNC (33,000 particles/cm3) was associated with an 11% [95% confidence interval (CI): 5, 17%] and 12% (95% CI: 6, 17%) FENO increase over baseline immediately and at 2 hr postexposure, respectively. A 7% (95% CI: 0.5, 14%) increase persisted until the following morning. These associations were robust and insensitive to adjustment for other pollutants. Similarly consistent associations were seen between FVC and FEV1 with PNC, NO2 (nitrogen dioxide), and NOx (nitrogen oxides). Conclusions: Changes in PNC, NO2, and NOx were associated with evidence of acute airway inflammation (i.e., FENO) and impaired lung function. PM mass concentration and PM10 oxidative potential were not predictive of the observed acute responses.

Strak, Maciej; Janssen, Nicole A.H; Godri, Krystal J; Gosens, Ilse; Mudway, Ian S; Cassee, Flemming R; Lebret, Erik; Kelly, Frank J; Harrison, Roy M; Steenhof, Maaike; Hoek, Gerard

2012-01-01

262

Presence of potentially pathogenic Babesia sp. for human in Ixodes ricinus in Switzerland.  

PubMed

We have designed and performed a new PCR method based on the 18S rRNA in order to individuate the presence and the identity of Babesia parasites. Out of 1159 Ixodes ricinus (Acari: Ixodidae) ticks collected in four areas of Switzerland, nine were found to contain Babesia DNA. Sequencing of the short amplicon obtained (411-452 bp) allowed the identification of three human pathogenic species: Babesia microti, B. divergens, for the first time in Switzerland, Babesia sp. EU1. We also report coinfections with B. sp. EU1-Borrelia burgdorferi sensu stricto and Babesia sp. EU1-B. afzelii. PMID:16841874

Casati, Simona; Sager, Heinz; Gern, Lise; Piffaretti, Jean-Claude

2006-01-01

263

Plant-isolated Pantoea agglomerans--new look into potential pathogenicity.  

PubMed

Pantoea agglomerans strains have been isolated from the surface of different edible plants which are major ingredients of traditional foods of the Black Sea region countries. Bacterial strains did not possess their pathogenic properties when tested routinely in vitro, but evinced the resistance to broad-spectrum antibiotics. Experiments on murine model (BALB/c mice) have demonstrated the ability of P. agglomerans to penetrate into internal organs and provoke the distinct dose-dependent physiological changes in the intestine and gut associated lymphoid tissues (GALT). PMID:23293827

Mudryk, M

264

Potentially pathogenic amoeba-associated microorganisms in cooling towers and their control.  

PubMed

Cooling towers provide a favorable environment for the proliferation of microorganisms. Cooling towers generate a biofilm and often aerosolize contaminated water, thereby increasing the risk of microorganism dissemination by human inhalation. This pathogen dissemination was first revealed by the epidemics of Legionnaires' disease that were directly related to the presence of cooling towers, and since then, the ecology of Legionella pneumophila has been well studied. Each country has specific standards regarding the acceptable amount of microorganisms in cooling tower systems. However, those standards typically only concern L. pneumophila, even though many other microorganisms can also be isolated from cooling towers, including protozoa, bacteria and viruses. Microbiological control of the cooling tower system can be principally achieved by chemical treatments and also by improving the system's construction. Several new treatments are being studied to improve the efficiency of disinfection. However, as most of these treatments continue to focus solely on L. pneumophila, reports of other types of pathogens continue to increase. Therefore, how their dissemination affects the human populous health should be addressed now. PMID:19492970

Pagnier, Isabelle; Merchat, Michèle; La Scola, Bernard

2009-06-01

265

Carbon nanotubes as delivery systems for respiratory disease: do the dangers outweigh the potential benefits?  

PubMed

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. PMID:22082164

Bonner, James C

2011-12-01

266

[Serologic studies of domestic cats for potential human pathogenic virus infections from wild rodents].  

PubMed

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) test, in which the same sera showed titres of 4-32. These data imply that, at least in Austria, unrecognized or subclinical orthopoxvirus infection in cats is more common than previously thought. In contrast to orthopoxviruses, all serum samples proved negative to parapoxvirus (parapoxvirus bovis 1) in VN test. In the same 200 samples, a seroprevalence of 5% was found to hantavirus (immunofluorescence antibody assay), indicating that domestic cats are susceptible to this virus and that infection is not uncommon in cat populations. Because higher titres were obtained against the Puumala serotype compared to the more pathogenic serotype Hantaan, it is most likely that the cats had experienced Puumala infections. Using HI test, antibodies to encephalomyocarditis virus (EMCV) were demonstrated in only 1.5% of the feline serum samples; although the antibody titres were low (16 and 32, respectively) we consider them specific, because these sera proved positive in VN test as well. Nevertheless, EMCV infection in domestic cats seems to be of low importance. The serological results presented in this paper, together with virological and epidemiological data, indicate that the domestic cat plays an important role only in the transmission of orthopoxviruses to human beings, but not in the case of parapox-, hanta-, and encephalomyocarditis virus. PMID:9409901

Nowotny, N

1996-05-01

267

Investigations on the prevalence and potential pathogenicity of intestinal trichomonads in pigs using in situ hybridization  

PubMed Central

In pigs, three different trichomonad species (Tritrichomonas foetus, Tetratrichomonas buttreyi and Tritrichomonas rotunda) have been described as commensals in the large intestine. The aim of this study was to gain further knowledge on the prevalence and pathogenicity of trichomonads in pigs by using a morphology-based approach. Chromogenic in situ hybridization (ISH) is a technique which allows direct localization of the protozoa in the intestinal tissue and correlation of the infection with pathologic changes. In the present study paraffin-wax embedded colon and ileum samples of 192 pigs were analyzed with this method. Using a probe specific for all known members of the order Trichomonadida (OT) 100 of the 192 pigs were tested positive. Thereof, about 10% showed moderate to high-grade parasitic load with trichomonads invading the lamina propria. Partial 18S ribosomal RNA gene sequencing of six of those animals showed a 100% sequence identity with T. foetus sequences. The majority of these animals were also tested positive for other enteropathogenic agents, such as Brachyspira sp., Lawsonia intracellularis, Escherichia coli, and porcine circovirus type 2. All OT-positive samples were further examined with another probe complementary to all known Tritrichomonas species sequences including T. foetus, T. augusta, T. mobilensis and T. nonconforma resulting in only 48 positives. These results suggest that T. foetus may not only be considered as an intestinal commensal but rather a facultative pathogen of pigs with a tendency for tissue invasion in the presence of other agents. Furthermore, the existence of other – yet to be identified – trichomonad species in the colon of pigs was shown.

Mostegl, Meike M.; Richter, Barbara; Nedorost, Nora; Maderner, Anton; Dinhopl, Nora; Weissenbock, Herbert

2011-01-01

268

Investigations on the prevalence and potential pathogenicity of intestinal trichomonads in pigs using in situ hybridization.  

PubMed

In pigs, three different trichomonad species (Tritrichomonas foetus, Tetratrichomonas buttreyi and Tritrichomonas rotunda) have been described as commensals in the large intestine. The aim of this study was to gain further knowledge on the prevalence and pathogenicity of trichomonads in pigs by using a morphology-based approach. Chromogenic in situ hybridization (ISH) is a technique which allows direct localization of the protozoa in the intestinal tissue and correlation of the infection with pathologic changes. In the present study paraffin-wax embedded colon and ileum samples of 192 pigs were analyzed with this method. Using a probe specific for all known members of the order Trichomonadida (OT) 100 of the 192 pigs were tested positive. Thereof, about 10% showed moderate to high-grade parasitic load with trichomonads invading the lamina propria. Partial 18S ribosomal RNA gene sequencing of six of those animals showed a 100% sequence identity with T. foetus sequences. The majority of these animals were also tested positive for other enteropathogenic agents, such as Brachyspira sp., Lawsonia intracellularis, Escherichia coli, and porcine circovirus type 2. All OT-positive samples were further examined with another probe complementary to all known Tritrichomonas species sequences including T. foetus, T. augusta, T. mobilensis and T. nonconforma resulting in only 48 positives. These results suggest that T. foetus may not only be considered as an intestinal commensal but rather a facultative pathogen of pigs with a tendency for tissue invasion in the presence of other agents. Furthermore, the existence of other - yet to be identified - trichomonad species in the colon of pigs was shown. PMID:21236578

Mostegl, Meike M; Richter, Barbara; Nedorost, Nora; Maderner, Anton; Dinhopl, Nora; Weissenböck, Herbert

2010-12-22

269

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...

270

Ultrahigh Resolution and Full-length Pilin Structures with Insights for Filament Assembly, Pathogenic Functions, and Vaccine Potential*  

PubMed Central

Pilin proteins assemble into Type IV pili (T4P), surface-displayed bacterial filaments with virulence functions including motility, attachment, transformation, immune escape, and colony formation. However, challenges in crystallizing full-length fiber-forming and membrane protein pilins leave unanswered questions regarding pilin structures, assembly, functions, and vaccine potential. Here we report pilin structures of full-length DnFimA from the sheep pathogen Dichelobacter nodosus and FtPilE from the human pathogen Francisella tularensis at 2.3 and 1 ? resolution, respectively. The DnFimA structure reveals an extended kinked N-terminal ?-helix, an unusual centrally located disulfide, conserved subdomains, and assembled epitopes informing serogroup vaccines. An interaction between the conserved Glu-5 carboxyl oxygen and the N-terminal amine of an adjacent subunit in the crystallographic dimer is consistent with the hypothesis of a salt bridge between these groups driving T4P assembly. The FtPilE structure identifies an authentic Type IV pilin and provides a framework for understanding the role of T4P in F. tularensis virulence. Combined results define a unified pilin architecture, specialized subdomain roles in pilus assembly and function, and potential therapeutic targets.

Hartung, Sophia; Arvai, Andrew S.; Wood, Timothy; Kolappan, Subramaniapillai; Shin, David S.; Craig, Lisa; Tainer, John A.

2011-01-01

271

Temporal and spatial distribution patterns of potentially pathogenic Vibrio spp. at recreational beaches of the German north sea.  

PubMed

The number of reported Vibrio-related wound infections associated with recreational bathing in Northern Europe has increased within the last decades. In order to study the health risk from potentially pathogenic Vibrio spp. in the central Wadden Sea, the seasonal and spatial distribution of Vibrio vulnificus, Vibrio parahaemolyticus, Vibrio alginolyticus and Vibrio cholerae were investigated at ten recreational beaches in this area over a 2-year period. V. alginolyticus and V. parahaemolyticus were found to be omnipresent all year round in the study area, while V. vulnificus occurrence was restricted to summer months in the estuaries of the rivers Ems and Weser. Multiple linear regression models revealed that water temperature is the most important determinant of Vibrio spp. occurrence in the area. Differentiated regression models showed a species-specific response to water temperature and revealed a particularly strong effect of even minor temperature increases on the probability of detecting V. vulnificus in summer. In sediments, Vibrio spp. concentrations were up to three orders of magnitude higher than in water. Also, V. alginolyticus and V. parahaemolyticus were found to be less susceptible towards winter temperatures in the benthic environment than in the water, indicating an important role of sediments for Vibrio ecology. While only a very small percentage of tested V. parahaemolyticus proved to be potentially pathogenic, the presence of V. vulnificus during the summer months should be regarded with care. PMID:23563708

Böer, Simone I; Heinemeyer, Ernst-August; Luden, Katrin; Erler, René; Gerdts, Gunnar; Janssen, Frank; Brennholt, Nicole

2013-04-07

272

A profile of amino acid and catecholamine levels during endotoxin-induced acute lung injury in sheep: Searching for potential markers of the acute respiratory distress syndrome  

Microsoft Academic Search

The identification of plasma markers of the course of the acute respiratory distress syndrome (ARDS) is needed to improve its treatment and to further advance the development of new therapeutic agents. The status of markers of lung injury in ARDS is reviewed and some new potential markers are proposed. This study focused on plasma amino acids, related amino compounds, and

James M. Hofford; Louis Milakofsky; Sidney Pell; Wolfgang Vogel

1996-01-01

273

Impact of Implementing 5 Potentially Better Respiratory Practices on Neonatal Outcomes and Costs  

PubMed Central

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.

Kalish, Leslie A.; LaPierre, Justine; Welch, Maureen; Porter, Virginia

2011-01-01

274

High frequency of potentially pathogenic SORL1 mutations in autosomal dominant early-onset Alzheimer disease.  

PubMed

Performing exome sequencing in 14 autosomal dominant early-onset Alzheimer disease (ADEOAD) index cases without mutation on known genes (amyloid precursor protein (APP), presenilin1 (PSEN1) and presenilin2 (PSEN2)), we found that in five patients, the SORL1 gene harbored unknown nonsense (n=1) or missense (n=4) mutations. These mutations were not retrieved in 1500 controls of same ethnic origin. In a replication sample, including 15 ADEOAD cases, 2 unknown non-synonymous mutations (1 missense, 1 nonsense) were retrieved, thus yielding to a total of 7/29 unknown mutations in the combined sample. Using in silico predictions, we conclude that these seven private mutations are likely to have a pathogenic effect. SORL1 encodes the Sortilin-related receptor LR11/SorLA, a protein involved in the control of amyloid beta peptide production. Our results suggest that besides the involvement of the APP and PSEN genes, further genetic heterogeneity, involving another gene of the same pathway is present in ADEOAD. PMID:22472873

Pottier, C; Hannequin, D; Coutant, S; Rovelet-Lecrux, A; Wallon, D; Rousseau, S; Legallic, S; Paquet, C; Bombois, S; Pariente, J; Thomas-Anterion, C; Michon, A; Croisile, B; Etcharry-Bouyx, F; Berr, C; Dartigues, J-F; Amouyel, P; Dauchel, H; Boutoleau-Bretonnière, C; Thauvin, C; Frebourg, T; Lambert, J-C; Campion, D

2012-04-03

275

Antimicrobial potential for the combination of bovine lactoferrin or its hydrolysate with lactoferrin-resistant probiotics against foodborne pathogens.  

PubMed

Previous reports have shown that several probiotic strains can resist the antibacterial activity of bovine lactoferrin (bLf), but the results are inconsistent. Moreover, a portion of orally administered apo-bLf is digested in vivo by pepsin to yield bLf hydrolysate, which produces stronger antibacterial activity than that observed with apo-bLf. However, whether bLf hydrolysate affects the growth of probiotic strains is unclear. Therefore, various probiotic strains in Taiwan were collected and evaluated for activity against apo-bLf and bLf hydrolysate in vitro. Thirteen probiotic strains were evaluated, and the growth of Lactobacillus acidophilus ATCC 4356, Lactobacillus salivarius ATCC 11741, Lactobacillus rhamnosus ATCC 53103, Bifidobacterium longum ATCC 15707, and Bifidobacterium lactis BCRC 17394 were inhibited by both apo-bLf and bLf hydrolysate. The growth of 8 strains were not affected by apo-bLf and bLf hydrolysate, including L. rhamnosus ATCC 7469, Lactobacillus reuteri ATCC 23272, Lactobacillus fermentum ATCC 11739, Lactobacillus coryniformis ATCC 25602, L. acidophilus BCRC 14065, Bifidobacterium infantis ATCC 15697, Bifidobacterium bifidum ATCC 29521, and Pediococcus acidilactici ATCC 8081. However, apo-bLf and its hydrolysate inhibited the growth of foodborne pathogens, including Escherichia coli, Salmonella typhimurium, Staphylococcus aureus, and Enterococcus faecalis. Moreover, the supernatants produced by L. fermentum, B. lactis, and B. longum inhibited the growth of most pathogens. Importantly, a combination of apo-bLf or bLf hydrolysate with the supernatants of cultures of the organisms described above showed synergistic or partially synergistic effects against the growth of most of the selected pathogens. In conclusion, several probiotic strains are resistant to apo-bLf and bLf hydrolysate, warranting clinical studies to evaluate the antimicrobial potential for the combination of apo-bLf or its hydrolysate with specific probiotics. PMID:23332852

Chen, P-W; Jheng, T T; Shyu, C-L; Mao, F C

2013-01-16

276

Comparison of pig and ferret models for evaluation of respiratory versus alimentary transmission of H5N1 high pathogenicity avian influenza virus  

Technology Transfer Automated Retrieval System (TEKTRAN)

Background: H5N1 high pathogenicity avian influenza viruses (HPAIV) have caused over 300 human infections and over 200 deaths since 2003. The majority of the cases have involved close direct or indirect contact with infected poultry but a few cases have incriminated consumption of uncooked poultry p...

277

The Australian bush fly (Musca vetustissima) as a potential vector in the transmission of foodborne pathogens at outdoor eateries.  

PubMed

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. PMID:19895260

Vriesekoop, Frank; Shaw, Rachel

2010-03-01

278

Fungal pathogens of Euphorbia heterophylla and E. hirta in Brazil and their potential as weed biocontrol agents.  

PubMed

A two-year survey of the fungi associated with two important congeneric pantropical weeds, Euphorbia heterophylla and E. hirta, was conducted in part of their native range in southern Brazil. Sampling was concentrated mainly in Rio de Janeiro State and ten species were identified as pathogens of these weeds. Two taxa, Botrytis ricini and Uromyces euphorbiae, were common to both weed hosts. Alternaria euphorbiicola, Bipolaris euphorbiae, Melampsora sp., Oidium sp. and Sphaceloma poinsettiae were recorded only from E. heterophylla, whereas Colletotrichum gloeosporioides, Sphaceloma sp. and Sphaerotheca fuliginea were restricted to E. hirta. Botrytis ricini and Colletotrichum gloeosporioides are new records for E. hirta, and Alternaria euphorbiicola and Sphaerotheca fuliginea are new host records for Brazil. Bipolaris euphorbiae, previously identified as Helminthosporium sp., is considered to be the correct name for the causal agent of a major disease of E. heterophyllum in Brazil. The potential of these pathogens as biocontrol agents is discussed and the mycobiota associated with both these weeds worldwide is reviewed. PMID:16284862

Barreto, R W; Evans, H C

1998-01-01

279

Mosquito species abundance and diversity in Malindi, Kenya and their potential implication in pathogen transmission.  

PubMed

Mosquitoes (Diptera: Culicidae) are important vectors of human disease-causing pathogens. Mosquitoes are found both in rural and urban areas. Deteriorating infrastructure, poor access to health, water and sanitation services, increasing population density, and widespread poverty contribute to conditions that modify the environment, which directly influences the risk of disease within the urban and peri-urban ecosystem. The objective of this study was to evaluate the mosquito vector abundance and diversity in urban, peri-urban, and rural strata in Malindi along the Kenya coast. The study was conducted in the coastal district of Malindi between January and December 2005. Three strata were selected which were described as urban, peri-urban, and rural. Sampling was done during the wet and dry seasons. Sampling in the wet season was done in the months of April and June to cover the long rainy season and in November and December to cover the short rainy season, while the dry season was between January and March and September and October. Adult mosquito collection was done using Pyrethrum Spray Collection (PSC) and Centers for Disease Control and Prevention (CDC) light traps inside houses and specimens were identified morphologically. In the three strata (urban, peri-urban, and rural), 78.5% of the total mosquito (n?=?7,775) were collected using PSC while 18.1% (n?=?1,795) were collected using the CDC light traps. Using oviposition traps, mosquito eggs were collected and reared in the insectary which yielded 329 adults of which 83.8% (n?=?276) were Aedes aegypti and 16.2% (n?=?53) were Culex quinquefasciatus. The mosquito distribution in the three sites varied significantly in each collection site. Anopheles gambiae, Anopheles funestus and Anopheles coustani were predominant in the rural stratum while C. quinquefasciatus was mostly found in urban and peri-urban strata. However, using PSC and CDC light trap collection techniques, A. aegypti was only found in urban strata. In the three strata, mosquitoes were mainly found in high numbers during the wet season. Further, A. gambiae, C. quinquefasciatus, and A. aegypti mosquitoes were found occurring together inside the houses. This in turn exposes the inhabitants to an array of mosquito-borne diseases including malaria, bancroftian filariasis, and arboviruses (dengue fever, Yellow fever, Rift Valley fever, Chikungunya fever, and West Nile Virus). In conclusion, our findings provide useful information for the design of integrated mosquito and disease control programs in East African environments. PMID:21626425

Mwangangi, Joseph M; Midega, Janet; Kahindi, Samuel; Njoroge, Laban; Nzovu, Joseph; Githure, John; Mbogo, Charles M; Beier, John C

2011-05-31

280

Immunization of Primates with a Newcastle Disease Virus-Vectored Vaccine via the Respiratory Tract Induces a High Titer of Serum Neutralizing Antibodies against Highly Pathogenic Avian Influenza Virus?  

PubMed Central

The ongoing outbreak of highly pathogenic avian influenza virus (HPAIV) in birds, the incidence of transmission to humans with a resulting high mortality rate, and the possibility of a human pandemic warrant the development of effective human vaccines against HPAIV. We developed an experimental live-attenuated vaccine for direct inoculation of the respiratory tract based on recombinant avian Newcastle disease virus (NDV) expressing the hemagglutinin (HA) glycoprotein of H5N1 HPAIV (NDV-HA). Expression of the HPAIV HA gene slightly reduced NDV virulence, as evidenced by the increased mean embryo death time and reduced replication in chickens. NDV-HA was administered to African green monkeys in two doses of 2 × 107 infectious units each with a 28-day interval to evaluate the systemic and local antibody responses specific to H5N1 HPAIV. The virus was shed only at low titers from the monkeys, indicative of safety. Two doses of NDV-HA induced a high titer of H5N1 HPAIV-neutralizing serum antibodies in all of the immunized monkeys. Moreover, a substantial mucosal immunoglobulin A response was induced in the respiratory tract after one and two doses. The titers of neutralizing antibodies achieved in this study suggest that the vaccine would be likely to prevent mortality and reduce morbidity caused by the H5N1 HPAIV. In addition, induction of a local immune response in the respiratory tract is an important advantage that is likely to reduce or prevent transmission of the virus during an outbreak or a pandemic. This vaccine is a candidate for clinical evaluation in humans.

DiNapoli, Joshua M.; Yang, Lijuan; Suguitan, Amorsolo; Elankumaran, Subbiah; Dorward, David W.; Murphy, Brian R.; Samal, Siba K.; Collins, Peter L.; Bukreyev, Alexander

2007-01-01

281

Exploration of antimicrobial potential of essential oils of Cinnamomum glanduliferum, Feronia elephantum, Bupleurum hamiltonii and Cyclospermum leptophyllum against foodborne pathogens.  

PubMed

Abstract Context: Cinnamomum glanduliferum (Wall.) Meissn. (Lauraceae), Feronia elephantum Correa (Rutaceae), Bupleurum hamiltonii Balak (Apiaceae) and Cyclospermum leptophyllum (Pers.) Sprague ex Britton & P. Wilson (Apiaceae) are common species found in Northwest Himalaya and are widely used as folk medicine. The study became more interesting because hitherto there are no reports on the antimicrobial screening of these species with specific chemical composition. Objective: The antimicrobial potential of the essential oils of C. glanduliferum, F. elephantum, B. hamiltonii and C. leptophyllum against some commonly occurring foodborne pathogenic and spoilage bacteria was explored in this study. Materials and methods: Antimicrobial screening studies of essential oils were performed against some Gram-positive and Gram-negative bacterial strains using broth-dilution methods. Each essential oil was prepared by serial double dilution method to get final concentrations ranging from 0.85--440.0?µg/ml in a 96 microtiter plate. Results: The in vitro studies revealed that C. glanduliferum oil was very active against Gram-negative bacteria, A. salmonicida (MIC 1.72?µg/ml), E. coli (MIC 3.43?µg/ml), and P. aeruginosa (MIC 3.43?µg/ml) as compared to the standards gentamicin and kanamicin. Oil of C. leptophyllum exhibited better inhibitory activity profile against Gram-positive S. aureus (MIC 3.43??g/ml) and Gram-negative E. herbicola (MIC 1.72??g/ml) and P. aeruginosa (MIC 3.43??g/ml) as compared to the standards. Discussion and conclusion: These results reveal that these essential oils may be used in the treatment of diseases caused by the foodborne pathogenic and spoilage bacteria. Their importance as potential medicinal agents is based on the antimicrobial findings. PMID:24033145

Singh, Charu; Singh, Shalini; Pande, Chitra; Tewari, Geeta; Pande, Veena; Sharma, Pratibha

2013-09-13

282

Profiles of Antibody Responses against Severe Acute Respiratory Syndrome Coronavirus Recombinant Proteins and Their Potential Use as Diagnostic Markers  

Microsoft Academic Search

A new coronavirus (severe acute respiratory syndrome coronavirus (SARS-CoV)) has been identified to be the etiological agent of severe acute respiratory syndrome. Given the highly contagious and acute nature of the disease, there is an urgent need for the development of diagnostic assays that can detect SARS-CoV infection. For determination of which of the viral proteins encoded by the SARS-CoV

Yee-Joo Tan; Phuay-Yee Goh; Burtram C. Fielding; Shuo Shen; Chih-Fong Chou; Jian-Lin Fu; Hoe Nam Leong; Yee Sin Leo; Eng Eong Ooi; Ai Ee Ling; Seng Gee Lim; Wanjin Hong

2004-01-01

283

The potential spread of highly pathogenic avian influenza virus via dynamic contacts between poultry premises in Great Britain  

PubMed Central

Background Highly pathogenic avian influenza (HPAI) viruses have had devastating effects on poultry industries worldwide, and there is concern about the potential for HPAI outbreaks in the poultry industry in Great Britain (GB). Critical to the potential for HPAI to spread between poultry premises are the connections made between farms by movements related to human activity. Movement records of catching teams and slaughterhouse vehicles were obtained from a large catching company, and these data were used in a simulation model of HPAI spread between farms serviced by the catching company, and surrounding (geographic) areas. The spread of HPAI through real-time movements was modelled, with the addition of spread via company personnel and local transmission. Results The model predicted that although large outbreaks are rare, they may occur, with long distances between infected premises. Final outbreak size was most sensitive to the probability of spread via slaughterhouse-linked movements whereas the probability of onward spread beyond an index premises was most sensitive to the frequency of company personnel movements. Conclusions Results obtained from this study show that, whilst there is the possibility that HPAI virus will jump from one cluster of farms to another, movements made by catching teams connected fewer poultry premises in an outbreak situation than slaughterhouses and company personnel. The potential connection of a large number of infected farms, however, highlights the importance of retaining up-to-date data on poultry premises so that control measures can be effectively prioritised in an outbreak situation.

2011-01-01

284

Recent progress on phospholipases: different sources, assay methods, industrial potential and pathogenicity.  

PubMed

Significant studies on phospholipases optimization, characterization, physiological role and industrial potential have been conducted worldwide. Some of them have been directed for biotechnological advances such as gene discovery and functional enhancement by protein engineering. Others reported phospholipases as virulence factor and major cause of pathophysiological effects. A general overview on phospholipase is needed for the identification of new reliable and efficient phospholipase, which would be potentially used in number of industrial and medical applications. Phospholipases catalyse the hydrolysis of one or more ester and phosphodiester bonds of glycerophospholipids. They vary in site of action on phospholipid which can be used industrially for modification/production of new phospholipids. Catalytically active phospholipase mainly use phosphatidylcholine as major substrate, but they can also show specificity with other phospholipids. Several accurate phospholipase assay methods are known, but a rapid and reliable method for high-throughput screening is still a challenge for efficient supply of superior phospholipases and their practical applications. Major application of phospholipase is in industries like oil refinery, health food manufacturing, dairy, cosmetics etc. All types of phospholipases can be involved as virulence factor. They can also be used as diagnostic markers for microbial infection. The importance of phospholipase in virulence is proven and inhibitors of the enzyme can be used as candidate for preventing the associated disease. PMID:21302142

Ramrakhiani, Lata; Chand, Subhash

2011-02-08

285

Urine Metabolomic Analysis Identifies Potential Biomarkers and Pathogenic Pathways in Kidney Cancer  

PubMed Central

Abstract Kidney cancer is the seventh most common cancer in the Western world, its incidence is increasing, and it is frequently metastatic at presentation, at which stage patient survival statistics are grim. In addition, there are no useful biofluid markers for this disease, such that diagnosis is dependent on imaging techniques that are not generally used for screening. In the present study, we use metabolomics techniques to identify metabolites in kidney cancer patients' urine, which appear at different levels (when normalized to account for urine volume and concentration) from the same metabolites in nonkidney cancer patients. We found that quinolinate, 4-hydroxybenzoate, and gentisate are differentially expressed at a false discovery rate of 0.26, and these metabolites are involved in common pathways of specific amino acid and energetic metabolism, consistent with high tumor protein breakdown and utilization, and the Warburg effect. When added to four different (three kidney cancer-derived and one “normal”) cell lines, several of the significantly altered metabolites, quinolinate, ?-ketoglutarate, and gentisate, showed increased or unchanged cell proliferation that was cell line-dependent. Further evaluation of the global metabolomics analysis, as well as confirmation of the specific potential biomarkers using a larger sample size, will lead to new avenues of kidney cancer diagnosis and therapy.

Kim, Kyoungmi; Taylor, Sandra L.; Ganti, Sheila; Guo, Lining; Osier, Michael V.

2011-01-01

286

Occurrence of potentially pathogenic vibrios and related environmental factors in Songkhla Lake, Thailand.  

PubMed

Vibrios are halophilic bacteria that are ubiquitous in marine environments. Their occurrence in tropical lakes has rarely been investigated. In this study, the predominance and diversity of Vibrio spp. was investigated over a 12-month period in a coastal lagoon, Songkhla Lake, in southern Thailand. Water samples were collected at 2 stations in the estuary near Yor Island in Songkhla Lake. The predominant vibrios were detected by a culture-based method, using thiosulfate-citrate-bile salt-sucrose agar and CHROMagar Vibrio. The diversity of Vibrio spp. was evaluated using denaturant density gradient electrophoresis (DGGE). The highest numbers of total vibrios and Vibrio parahaemolyticus in both areas were observed during the summer. There was no significant correlation between the numbers of vibrios, including V. parahaemolyticus, and either the water temperature or plankton density. Variations in Vibrio species were observed with changes in salinity. Vibrio parahaemolyticus and V. cholerae non-O1/non-O139 were detected during the rainy season when the salinity dropped to nearly 0 parts per thousand. In both areas, V. alginolyticus was the most prominent species detected by the culture method, whereas Vibrio parahaemolyticus was detected by DGGE, every month. Other Vibrio spp. of potential public health concern were also detected by the culture method; they included V. vulnificus , V. fluvialis , and V. mimicus . PMID:22014235

Thongchankaew, Uraiwan; Mittraparp-arthorn, Pimonsri; Sukhumungoon, Pharanai; Tansila, Natta; Nuidate, Taiyeebah; Nishibuchi, Mitsuaki; Vuddhakul, Varaporn

2011-10-20

287

Caspase Dependent Programmed Cell Death in Developing Embryos: A Potential Target for Therapeutic Intervention against Pathogenic Nematodes  

PubMed Central

Background Successful embryogenesis is a critical rate limiting step for the survival and transmission of parasitic worms as well as pathology mediated by them. Hence, blockage of this important process through therapeutic induction of apoptosis in their embryonic stages offers promise for developing effective anti-parasitic measures against these extra cellular parasites. However, unlike in the case of protozoan parasites, induction of apoptosis as a therapeutic approach is yet to be explored against metazoan helminth parasites. Methodology/Principal Findings For the first time, here we developed and evaluated flow cytometry based assays to assess several conserved features of apoptosis in developing embryos of a pathogenic filarial nematode Setaria digitata, in-vitro as well as ex-vivo. We validated programmed cell death in developing embryos by using immuno-fluorescence microscopy and scoring expression profile of nematode specific proteins related to apoptosis [e.g. CED-3, CED-4 and CED-9]. Mechanistically, apoptotic death of embryonic stages was found to be a caspase dependent phenomenon mediated primarily through induction of intracellular ROS. The apoptogenicity of some pharmacological compounds viz. DEC, Chloroquine, Primaquine and Curcumin were also evaluated. Curcumin was found to be the most effective pharmacological agent followed by Primaquine while Chloroquine displayed minimal effect and DEC had no demonstrable effect. Further, demonstration of induction of apoptosis in embryonic stages by lipid peroxidation products [molecules commonly associated with inflammatory responses in filarial disease] and demonstration of in-situ apoptosis of developing embryos in adult parasites in a natural bovine model of filariasis have offered a framework to understand anti-fecundity host immunity operational against parasitic helminths. Conclusions/Significance Our observations have revealed for the first time, that induction of apoptosis in developing embryos can be a potential approach for therapeutic intervention against pathogenic nematodes and flow cytometry can be used to address different issues of biological importance during embryogenesis of parasitic worms.

Mohapatra, Alok Das; Kumar, Sunil; Satapathy, Ashok Kumar; Ravindran, Balachandran

2011-01-01

288

Loofah sponges as reservoirs and vehicles in the transmission of potentially pathogenic bacterial species to human skin.  

PubMed Central

Loofah sponges are natural products used as exfoliative beauty aids. As a consequence of tracing a case of Pseudomonas aeruginosa folliculitis to a contaminated loofah sponge, we assessed the role of loofah sponges in supporting the growth of a wide variety of bacterial species. Our data show growth enhancement of sterile loofah fragments for numerous gram-negative (Pseudomonas, Xanthomonas, and Klebsiella) and gram-positive (Enterococcus and group B Streptococcus) species of human and environmental origin. Furthermore, hydrated new, unused loofah sponges undergo a shift in bacterial flora from sparse colonies of Bacillus spp. and Staphylococcus epidermidis to a predominantly gram-negative flora. The growth-promoting potential of loofah sponges (and other exfoliatives) can be further augmented by desquamated epithelial cells entrapped in the loofah fibrous matrix. Therefore, as loofah sponges (and other exfoliatives) can serve as a reservoir and a vehicle for the transmission of potentially pathogenic species to the human skin, we recommend their decontamination with hypochlorite (10%) bleach at regular intervals. Images

Bottone, E J; Perez, A A; Oeser, J L

1994-01-01

289

Combining inferential and deductive approaches to estimate the potential geographical range of the invasive plant pathogen, Phytophthora ramorum.  

PubMed

Phytophthora ramorum, an invasive plant pathogen of unknown origin, causes considerable and widespread damage in plant industries and natural ecosystems of the USA and Europe. Estimating the potential geographical range of P. ramorum has been complicated by a lack of biological and geographical data with which to calibrate climatic models. Previous attempts to do so, using either invaded range data or surrogate species approaches, have delivered varying results. A simulation model was developed using CLIMEX to estimate the global climate suitability patterns for establishment of P. ramorum. Growth requirements and stress response parameters were derived from ecophysiological laboratory observations and site-level transmission and disease factors related to climate data in the field. Geographical distribution data from the USA (California and Oregon) and Norway were reserved from model-fitting and used to validate the models. The model suggests that the invasion of P. ramorum in both North America and Europe is still in its infancy and that it is presently occupying a small fraction of its potential range. Phytophthora ramorum appears to be climatically suited to large areas of Africa, Australasia and South America, where it could cause biodiversity and economic losses in plant industries and natural ecosystems with susceptible hosts if introduced. PMID:23667628

Ireland, Kylie B; Hardy, Giles E St J; Kriticos, Darren J

2013-05-07

290

The effect of activation of the lactoperoxidase system and souring on certain potential human pathogens in cows' milk.  

PubMed

Conventional methods of ensuring the safety and soundness of cows' milk for human consumption, such as pasteurisation, are not always practical in poor socioeconomic conditions or in rural communities that lack modern amenities. Activation of lactoperoxidase (LP) system and souring of milk were investigated as potential alternative methods to sustain the safety of milk by inhibiting certain microorganisms with known pathogenic potential. The activation of the LP-system inhibited the growth of Staphylococcus aureus and Escherichia coli by the order of 2 log values. The inhibition of Brucella abortus was negligible. The replication of Coxiella burnetti in milk was not disturbed even after 17 h of LP-system activation at 20 degrees C, but the outcome of the LP-system treatment on Mycobacterium bovis could not be determined as the conventional culturing technique used to grow this organism did not allow full recovery. Souring inhibited the growth of S. aureus and E. coli also by the order of 2 log values. From the results obtained in this investigation are concluded that the activation of the LP-system and souring can be used to inhibit the growth of S. aureus and E. coli in cows' milk, thereby increasing its safety. PMID:9561497

Kangumba, J G; Venter, E H; Coetzer, J A

1997-12-01

291

Stochastic simulation of live salmonid movement in England and Wales to predict potential spread of exotic pathogens.  

PubMed

The anthropogenic movement of live fish has been identified as the most important route for the transmission of disease between river catchments. To assist in contingency planning for exotic salmonid disease outbreaks, a stochastic model was developed to assess the potential geographic distribution of an introduced pathogen with time to first detection. The Live Fish Movement Database (a resource funded by the UK Department for Environment, Food and Rural Affairs [Defra] and managed by the Centre for Environment, Fisheries and Aquaculture Science [CEFAS] and the Environment Agency [EA]) was used to establish details of live fish movement in England and Wales. A contact network was created for farm to farm and farm to non-farm (fishery) movements of rainbow trout Oncorhynchus mykiss, brown trout Salmo trutta and Atlantic salmon Salmo salar, and probability functions were used to model the timing and destination of movements from farm sites, based on these trading activities. Monte Carlo simulations were run to track the progression of potential disease transmission from single index farm inputs through river catchments with time. Two hundred farms exported fish to 1653 destinations in 147 of the total 198 river catchments. The median number of catchments contacted after 3 and 12 mo were 3 and 6, respectively. In 5% of simulations 63 or more catchments were contacted, and in 1% of simulations 75 or more catchments were contacted after 12 mo. These results may be used to underpin the development of contingency plans for exotic disease outbreaks. PMID:17140134

Thrush, Mark; Peeler, Edmund

2006-10-17

292

Influenza Virus Respiratory Infection and Transmission Following Ocular Inoculation in Ferrets  

PubMed Central

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 entry for establishment of a respiratory infection. However, the properties which govern ocular tropism of influenza viruses, the mechanisms of virus spread from ocular to respiratory tissue, and the potential differences in respiratory disease initiated from different exposure routes are poorly understood. Here, we established a ferret model of ocular inoculation to explore the development of virus pathogenicity and transmissibility following influenza virus exposure by the ocular route. We found that multiple subtypes of human and avian influenza viruses mounted a productive virus infection in the upper respiratory tract of ferrets following ocular inoculation, and were additionally detected in ocular tissue during the acute phase of infection. H5N1 viruses maintained their ability for systemic spread and lethal infection following inoculation by the ocular route. Replication-independent deposition of virus inoculum from ocular to respiratory tissue was limited to the nares and upper trachea, unlike traditional intranasal inoculation which results in virus deposition in both upper and lower respiratory tract tissues. Despite high titers of replicating transmissible seasonal viruses in the upper respiratory tract of ferrets inoculated by the ocular route, virus transmissibility to naïve contacts by respiratory droplets was reduced following ocular inoculation. These data improve our understanding of the mechanisms of virus spread following ocular exposure and highlight differences in the establishment of respiratory disease and virus transmissibility following use of different inoculation volumes and routes.

Belser, Jessica A.; Gustin, Kortney M.; Maines, Taronna R.; Pantin-Jackwood, Mary J.; Katz, Jacqueline M.; Tumpey, Terrence M.

2012-01-01

293

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

Microsoft Academic Search

Ticks are often infected with more than one pathogen, and several field surveys have documented nonrandom levels of coinfection.\\u000a Levels of coinfection by pathogens in four tick species were analyzed using published infection data. Coinfection patterns\\u000a of pathogens in field-collected ticks include numerous cases of higher or lower levels of coinfection than would be expected\\u000a due to chance alone, but

Howard S. Ginsberg

2008-01-01

294

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

Microsoft Academic Search

Ticks are often infected with more than one pathogen, and several field surveys have documented nonrandom levels of coinfection.\\u000a Levels of coinfection by pathogens in four tick species were analyzed using published infection data. Coinfection patterns\\u000a of pathogens in field-collected ticks include numerous cases of higher or lower levels of coinfection than would be expected\\u000a due to chance alone, but

Howard S. Ginsberg

295

A two-centre study for the evaluation and validation of an animal model for the assessment of the potential of small molecular weight chemicals to cause respiratory allergy  

Microsoft Academic Search

This study evaluated a single intradermal injection model in the guinea pig with subsequent inhalation challenge and serological analysis as a method to predict the potential of chemicals to induce respiratory allergy. Four known respiratory allergens (trimellitic anhydride, diphenyl methane diisocyanate, phthalic anhydride and toluene diisocyanate (TDI)) were screened by two industrial research laboratories using this protocol. Dinitrochlorobenzene, a potent

L. Blaikie; T. Morrow; A. P. Wilson; P. Hext; P. J. Hartop; N. J. Rattray; D. Woodcock; P. A. Botham

1995-01-01

296

Isolation and Characterization of Potentially Pathogenic Antimicrobial-Resistant Escherichia coli Strains from Chicken and Pig Farms in Spain? †  

PubMed Central

To ascertain whether on animal farms there reside extended-spectrum ?-lactamase (ESBL) and plasmidic class C ?-lactamase-producing Escherichia coli isolates potentially pathogenic for humans, phylogenetic analyses, pulsed-field gel electrophoresis (PFGE) typing, serotyping, and virulence genotyping were performed for 86 isolates from poultry (57 isolates) and pig (29 isolates) farms. E. coli isolates from poultry farms carried genes encoding enzymes of the CTX-M-9 group as well as CMY-2, whereas those from pig farms mainly carried genes encoding CTX-M-1 enzymes. Poultry and pig isolates differed significantly in their phylogenetic group assignments, with phylogroup A predominating in pig isolates and phylogroup D predominating in avian isolates. Among the 86 farm isolates, 23 (26.7%) carried two or more virulence genes typical of extraintestinal pathogenic E. coli (ExPEC). Of these, 20 were isolated from poultry farms and only 3 from pig farms. Ten of the 23 isolates belonged to the classic human ExPEC serotypes O2:H6, O2:HNM, O2:H7, O15:H1, and O25:H4. Despite the high diversity of serotypes and pulsotypes detected among the 86 farm isolates, 13 PFGE clusters were identified. Four of these clusters contained isolates with two or more virulence genes, and two clusters exhibited the classic human ExPEC serotypes O2:HNM (ST10) and O2:H6 (ST115). Although O2:HNM and O2:H6 isolates of human and animal origins differed with respect to their virulence genes and PFGE pulsotypes, the O2:HNM isolates from pigs showed the same sequence type (ST10) as those from humans. The single avian O15:H1 isolate was compared with human clinical isolates of this serotype. Although all were found to belong to phylogroup D and shared the same virulence gene profile, they differed in their sequence types (ST362-avian and ST393-human) and PFGE pulsotypes. Noteworthy was the detection, for the first time, in poultry farms of the clonal groups O25b:H4-ST131-B2, producing CTX-M-9, and O25a-ST648-D, producing CTX-M-32. The virulence genes and PFGE profiles of these two groups were very similar to those of clinical human isolates. While further studies are required to determine the true zoonotic potential of these clonal groups, our results emphasize the zoonotic risk posed especially by poultry farms, but also by pig farms, as reservoirs of ESBL- and CMY-2-encoding E. coli.

Cortes, Pilar; Blanc, Vanessa; Mora, Azucena; Dahbi, Ghizlane; Blanco, Jesus E.; Blanco, Miguel; Lopez, Cecilia; Andreu, Antonia; Navarro, Ferran; Alonso, Maria Pilar; Bou, German; Blanco, Jorge; Llagostera, Montserrat

2010-01-01

297

Effectiveness of serum megakaryocyte potentiating factor in evaluating the effects of chrysotile and its heated products on respiratory organs  

SciTech Connect

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.

Takata, Ayako [Department of Preventive Medicine, St. Marianna University School of Medicine, Kawasaki (Japan); Yamauchi, Hiroshi, E-mail: hyama@kitasato-u.ac.jp [Department of Public Health, School of Allied Health Science, Kitasato University, Sagamihara (Japan); Toya, Tadao [National Institute of Occupational Safety and Health, Kawasaki (Japan); Miyamoto-Kohno, Sayako; Iwatatsu, Yuka; Teranaka, Iroha [Department of Public Health, School of Allied Health Science, Kitasato University, Sagamihara (Japan); Aminaka, Masahito [Department of Preventive Medicine, St. Marianna University School of Medicine, Kawasaki (Japan); Yamashita, Kiyotsugu [Department of Public Health, School of Allied Health Science, Kitasato University, Sagamihara (Japan); Nozawa Corporation, Kobe (Japan); Kohyama, Norihiko [Natural Science Laboratory, Faculty of Economics, Toyo University, Tokyo (Japan)

2011-04-15

298

The impact of dosimetric optimization using respiratory gating and inhomogeneity corrections on potential therapeutic gain in patients with lung cancer  

NASA Astrophysics Data System (ADS)

Early stage lung cancer is found with increasing frequency by screening high risk patients. Recently, the use of Stereotactic Body Radiation Therapy (SBRT) has been found to be highly successful. The hypothesis being tested here is that the use of respiratory gating and tissue heterogeneity corrections are necessary to optimize tumor and normal tissue dose distributions for SBRT.

de La Fuente Herman, Tania

299

Respiratory tract lesions in guinea pigs exposed to sulfuric acid mist. [Mist is potential air pollutant from fossil fuel combustion  

Microsoft Academic Search

Guinea pigs were exposed in inhalation chambers to 25 mglm³ sulfuric acid mist 6 h\\/d for 2 d, and the acute respiratory effects were correlated by light and electron microscopy. This concentration of acid was selected since lower concentrations result in only slight effects while higher concentrations result in death. By light microscopy, the most prominent pulmonary lesion at 48

B. Y. Cockrell; W. M. Busey; F. L. Cavender

1978-01-01

300

A Study Quantifying the Hand-to-Face Contact Rate and Its Potential Application to Predicting Respiratory Tract Infection  

Microsoft Academic Search

A substantial portion of human respiratory tract infection is thought to be transmitted via contaminated hand contact with the mouth, eyes, and\\/or nostrils. Thus, a key risk factor for infection transmission should be the rate of hand contact with these areas termed target facial membranes. A study was conducted in which 10 subjects were each videotaped for 3 hr while

Mark Nicas; Daniel Best

2008-01-01

301

Addressing Potential Contaminants in Soil for the Study of Pathogenic E. coli O157 and O8 Strains  

Technology Transfer Automated Retrieval System (TEKTRAN)

Introduction: Foodborne illness associated with leafy greens has illustrated the need for information describing the transmission of pathogens via contaminated soil-amendments. A realistic means of studying the fate of pathogens simulating natural conditions proved difficult due to high levels of ba...

302

Pasteurella multocida and bovine respiratory disease.  

PubMed

Pasteurella multocida is a pathogenic Gram-negative bacterium that has been classified into three subspecies, five capsular serogroups and 16 serotypes. P. multocida serogroup A isolates are bovine nasopharyngeal commensals, bovine pathogens and common isolates from bovine respiratory disease (BRD), both enzootic calf pneumonia of young dairy calves and shipping fever of weaned, stressed beef cattle. P. multocida A:3 is the most common serotype isolated from BRD, and these isolates have limited heterogeneity based on outer membrane protein (OMP) profiles and ribotyping. Development of P. multocida-induced pneumonia is associated with environmental and stress factors such as shipping, co-mingling, and overcrowding as well as concurrent or predisposing viral or bacterial infections. Lung lesions consist of an acute to subacute bronchopneumonia that may or may not have an associated pleuritis. Numerous virulence or potential virulence factors have been described for bovine respiratory isolates including adherence and colonization factors, iron-regulated and acquisition proteins, extracellular enzymes such as neuraminidase, lipopolysaccharide, polysaccharide capsule and a variety of OMPs. Immunity of cattle against respiratory pasteurellosis is poorly understood; however, high serum antibodies to OMPs appear to be important for enhancing resistance to the bacterium. Currently available P. multocida vaccines for use in cattle are predominately traditional bacterins and a live streptomycin-dependent mutant. The field efficacy of these vaccines is not well documented in the literature. PMID:18218157

Dabo, S M; Taylor, J D; Confer, A W

2007-12-01

303

Associations Between Multidrug Resistance, Plasmid Content, and Virulence Potential Among Extraintestinal Pathogenic and Commensal Escherichia coli from Humans and Poultry  

PubMed Central

Abstract The emergence of plasmid-mediated multidrug resistance (MDR) among enteric bacteria presents a serious challenge to the treatment of bacterial infections in humans and animals. Recent studies suggest that avian Escherichia coli commonly possess the ability to resist multiple antimicrobial agents, and might serve as reservoirs of MDR for human extraintestinal pathogenic Escherichia coli (ExPEC) and commensal E. coli populations. We determined antimicrobial susceptibility profiles for 2202 human and avian E. coli isolates, then sought for associations among resistance profile, plasmid content, virulence factor profile, and phylogenetic group. Avian-source isolates harbored greater proportions of MDR than their human counterparts, and avian ExPEC had higher proportions of MDR than did avian commensal E. coli. MDR was significantly associated with possession of the IncA/C, IncP1-?, IncF, and IncI1 plasmid types. Overall, inferred virulence potential did not correlate with drug susceptibility phenotype. However, certain virulence genes were positively associated with MDR, including ireA, ibeA, fyuA, cvaC, iss, iutA, iha, and afa. According to the total dataset, isolates segregated significantly according to host species and clinical status, thus suggesting that avian and human ExPEC and commensal E. coli represent four distinct populations with limited overlap. These findings suggest that in extraintestinal E. coli, MDR is most commonly associated with plasmids, and that these plasmids are frequently found among avian-source E. coli from poultry production systems.

Johnson, Timothy J.; Logue, Catherine M.; Johnson, James R.; Kuskowski, Michael A.; Sherwood, Julie S.; Barnes, H. John; DebRoy, Chitrita; Wannemuehler, Yvonne M.; Obata-Yasuoka, Mana; Spanjaard, Lodewijk

2012-01-01

304

Identification of Common Biological Pathways and Drug Targets Across Multiple Respiratory Viruses Based on Human Host Gene Expression Analysis  

Microsoft Academic Search

BackgroundPandemic and seasonal respiratory viruses are a major global health concern. Given the genetic diversity of respiratory viruses and the emergence of drug resistant strains, the targeted disruption of human host-virus interactions is a potential therapeutic strategy for treating multi-viral infections. The availability of large-scale genomic datasets focused on host-pathogen interactions can be used to discover novel drug targets as

Steven B. Smith; William Dampier; Aydin Tozeren; James R. Brown; Michal Magid-Slav

2012-01-01

305

Plant extracts, spices, and essential oils inactivate E. coli O157:H7 pathogens and reduce formation of potentially carcinogenic heterocyclic amines in grilled beef patties  

Technology Transfer Automated Retrieval System (TEKTRAN)

Meats need to be sufficiently heated to inactivate foodborne pathogens such as Escherichia coli O157:H7. High-temperature heat treatment used to prepare well-done meats could, however, increase the formation of potentially carcinogenic heterocyclic amines (HCAs). The objective of this study was to ...

306

Emerging Respiratory Viruses: Challenges and Vaccine Strategies  

PubMed Central

The current threat of avian influenza to the human population, the potential for the reemergence of severe acute respiratory syndrome (SARS)-associated coronavirus, and the identification of multiple novel respiratory viruses underline the necessity for the development of therapeutic and preventive strategies to combat viral infection. Vaccine development is a key component in the prevention of widespread viral infection and in the reduction of morbidity and mortality associated with many viral infections. In this review we describe the different approaches currently being evaluated in the development of vaccines against SARS-associated coronavirus and avian influenza viruses and also highlight the many obstacles encountered in the development of these vaccines. Lessons learned from current vaccine studies, coupled with our increasing knowledge of the host and viral factors involved in viral pathogenesis, will help to increase the speed with which efficacious vaccines targeting newly emerging viral pathogens can be developed.

Gillim-Ross, Laura; Subbarao, Kanta

2006-01-01

307

Respiratory syncytial virus infection in high risk infants and the potential impact of prophylaxis in a United Kingdom cohort  

Microsoft Academic Search

BACKGROUNDBronchiolitis caused by respiratory syncytial virus (RSV) is an important cause of morbidity in ex-premature infants. In a randomised placebo controlled trial monoclonal antibody prophylaxis showed a 55% reduction in relative risk of hospital admission for these high risk infants, against a background incidence of 10.6 admissions per 100 high risk infants.AIMSTo follow a cohort of high risk infants in

Simon J Clark; Michael W Beresford; N V Subhedar; N J Shaw

2000-01-01

308

Phylogenetic identification of bacterial MazF toxin protein motifs among probiotic strains and foodborne pathogens and potential implications of engineered probiotic intervention in food  

PubMed Central

Background Toxin-antitoxin (TA) systems are commonly found in bacteria and Archaea, and it is the most common mechanism involved in bacterial programmed cell death or apoptosis. Recently, MazF, the toxin component of the toxin-antitoxin module, has been categorized as an endoribonuclease, or it may have a function similar to that of a RNA interference enzyme. Results In this paper, with comparative data and phylogenetic analyses, we are able to identify several potential MazF-conserved motifs in limited subsets of foodborne pathogens and probiotic strains and further provide a molecular basis for the development of engineered/synthetic probiotic strains for the mitigation of foodborne illnesses. Our findings also show that some probiotic strains, as fit as many bacterial foodborne pathogens, can be genetically categorized into three major groups based on phylogenetic analysis of MazF. In each group, potential functional motifs are conserved in phylogenetically distant species, including foodborne pathogens and probiotic strains. Conclusion These data provide important knowledge for the identification and computational prediction of functional motifs related to programmed cell death. Potential implications of these findings include the use of engineered probiotic interventions in food or use of a natural probiotic cocktail with specificity for controlling targeted foodborne pathogens.

2012-01-01

309

Annexin V Release and Transmembrane Mitochondrial Potential during Storage of Apheresis-Derived Platelets Treated for Pathogen Reduction  

PubMed Central

Summary Background In vitro function of stored platelet (PLT) con-centrates was analyzed after applying two different techniques of pathogen reduction technology (PRT) treatment, which could increase cellular injury during processing and storage. Methods Nine triple-dose PLT apheresis donations were split into 27 single units designated to riboflavin-UVB (M) or psoralen-UVA (I) treatment or remained untreated (C). Throughout 8 days of storage, samples were analyzed for annexin V release, the mitochondrial transmembrane potential (??) and some classical markers of PLT quality (pH, LDH release, hypotonic shock response (HSR)). Results PLT count and LDH release of all units maintained initial ranges. All units exhibited a decrease in pH and HSR and an increase in annexin V release and ?? disruption. Notably, throughout the entire storage period, annexin V release re-mained lowest in M units. Throughout 7 days of storage, M units remained comparable to C units (p > 0.05), whereas inferior values were observed with I units. Here, differences to C units reached significance by day 1 (pH: p < 0.0001), day 5 (annexin V release: p < 0.014), and day 7 (HSR, ??: p ? 0.003). After PRT treatment, annexin V release and ?? disruption were significantly (p < 0.001) correlated with pH and HSR. Conclusion During storage, all units showed a de-crease in HSR and an increase in acidity, annexin V release and ?? disruption. While M units remained comparable to C units, I units demonstrated significantly inferior values during terminal storage. This could have resulted from differences in PRT treatment or simply be due to differences in storage media and should be analyzed for clinical relevance in future investigations.

Picker, Susanne M.; Oustianskaia, Larissa; Schneider, Volker; Gathof, Birgit S.

2010-01-01

310

Uncoupling of photoreceptor peripherin/rds fusogenic activity from biosynthesis, subunit assembly, and targeting: a potential mechanism for pathogenic effects.  

PubMed

Inherited defects in the RDS gene cause a multiplicity of progressive retinal diseases in humans. The gene product, peripherin/rds (P/rds), is a member of the tetraspanin protein family required for normal vertebrate photoreceptor outer segment (OS) architecture. Although its molecular function remains uncertain, P/rds has been suggested to catalyze membrane fusion events required for the OS renewal process. This study investigates the importance of two charged residues within a predicted C-terminal helical region for protein biosynthesis, localization, and interaction with model membranes. Targeted mutagenesis was utilized to neutralize charges at Glu(321) and Lys(324) individually and in combination to generate three mutant variants. Studies were conducted on variants expressed as 1) full-length P/rds in COS-1 cells, 2) glutathione S-transferase fusion proteins in Escherichia coli, and 3) membrane-associated green fluorescent protein fusion proteins in transgenic Xenopus laevis. None of the mutations affected biosynthesis of full-length P/rds in COS-1 cells as assessed by Western blotting, sedimentation velocity, and immunofluorescence microscopy. Although all mutations reside within a recently identified localization signal, none altered the ability of this region to direct OS targeting in transgenic X. laevis retinas. In contrast, individual or simultaneous neutralization of the charged amino acids Glu(321) and Lys(324) abolished the ability of the C-terminal domain to promote model membrane fusion as assayed by lipid mixing. These results demonstrate that, although overlapping, C-terminal determinants responsible for OS targeting and fusogenicity are separable and that fusogenic activity has been uncoupled from other protein properties. The observation that subunit assembly and OS targeting can both proceed normally in the absence of fusogenic activity suggests that properly assembled and targeted yet functionally altered proteins could potentially generate pathogenic effects within the vertebrate photoreceptor. PMID:15252042

Ritter, Linda M; Boesze-Battaglia, Kathleen; Tam, Beatrice M; Moritz, Orson L; Khattree, Nidhi; Chen, Shu-Chu; Goldberg, Andrew F X

2004-07-13

311

Difference of genotypic and phenotypic characteristics and pathogenicity potential of Photobacterium damselae subsp. damselae between clinical and environmental isolates from Japan.  

PubMed

Photobacterium damselae subsp. damselae has been known as an opportunistic pathogen in fish and mammals. Human infectious cases are often very serious and occasionally fatal. We previously reportedtwo fatal cases caused by this subspecies where the patients developed multiple organ failure within 20-36 h after the onset of initial symptoms. Despite its ability to cause serious infections in humans, this subspecies has not been well studied because human infectious cases caused by this subspecies are very rare. However, this subspecies has been reported to be present in a wide range with high incidence rate in aquatic environments. Thus, we investigated the genotypic and phenotypic differences between clinical and environmental strains of Photobacterium damselae subsp. damselae. Using molecular typing methods, such as ribotyping, AFLP (Amplified Fragment Length Polymorphism), and PFGE (Pulsed-Field Gel Electrophoresis) and sequencing analysis, we determined that thetwo clinical strains were genetically similar yet distinguishable from environmental strains, but not significantly so. On the other hand, phenotypic differences were clear; moreover, mouse assay and hemolytic assay indicated strong pathogenicity of only clinical isolates. Based on these data, we concluded that there are differences in pathogenicity potential among isolates of this subspecies, and some environmental isolates have the potential to become highly pathogenic. PMID:18554860

Takahashi, Hajime; Miya, Satoko; Kimura, Bon; Yamane, Kunikazu; Arakawa, Yoshichika; Fujii, Tateo

2008-05-08

312

Comparative genomics of multiple strains of Pseudomonas cannabina pv. alisalensis, a potential model pathogen of both monocots and dicots.  

PubMed

Comparative genomics of closely related pathogens that differ in host range can provide insights into mechanisms of host-pathogen interactions and host adaptation. Furthermore, sequencing of multiple strains with the same host range reveals information concerning pathogen diversity and the molecular basis of virulence. Here we present a comparative analysis of draft genome sequences for four strains of Pseudomonas cannabina pathovar alisalensis (Pcal), which is pathogenic on a range of monocotyledonous and dicotyledonous plants. These draft genome sequences provide a foundation for understanding host range evolution across the monocot-dicot divide. Like other phytopathogenic pseudomonads, Pcal strains harboured a hrp/hrc gene cluster that codes for a type III secretion system. Phylogenetic analysis based on the hrp/hrc cluster genes/proteins, suggests localized recombination and functional divergence within the hrp/hrc cluster. Despite significant conservation of overall genetic content across Pcal genomes, comparison of type III effector repertoires reinforced previous molecular data suggesting the existence of two distinct lineages within this pathovar. Furthermore, all Pcal strains analyzed harbored two distinct genomic islands predicted to code for type VI secretion systems (T6SSs). While one of these systems was orthologous to known P. syringae T6SSs, the other more closely resembled a T6SS found within P. aeruginosa. In summary, our study provides a foundation to unravel Pcal adaptation to both monocot and dicot hosts and provides genetic insights into the mechanisms underlying pathogenicity. PMID:23555661

Sarris, Panagiotis F; Trantas, Emmanouil A; Baltrus, David A; Bull, Carolee T; Wechter, William Patrick; Yan, Shuangchun; Ververidis, Filippos; Almeida, Nalvo F; Jones, Corbin D; Dangl, Jeffery L; Panopoulos, Nickolas J; Vinatzer, Boris A; Goumas, Dimitrios E

2013-03-28

313

Chlamydia pneumoniae, Mycoplasma pneumoniae, and Legionella pneumophila in Elderly Patients With Stroke (C-PEPS, M-PEPS, L-PEPS) A Case-Control Study on the Infectious Burden of Atypical Respiratory Pathogens in Elderly Patients With Acute Cerebrovascular Disease  

Microsoft Academic Search

Background and Purpose—Multiple studies have suggested an association between Chlamydia pneumoniae and Mycoplasma pneumoniae infection and cardiovascular disease. We investigated whether the risk of cerebrovascular disease is associated with Legionella pneumophila infection and the aggregate number\\/infectious burden of these atypical respiratory pathogens. Methods—One hundred patients aged 65 years admitted with acute stroke or transient ischemic attack (TIA) and 87 control

Joseph Ngeh; Colin Goodbourn

314

What makes pathogens pathogenic  

PubMed Central

Metazoans contain multiple complex microbial ecosystems in which the balance between host and microbe can be tipped from commensalism to pathogenicity. This transition is likely to depend both on the prevailing environmental conditions and on specific gene-gene interactions placed within the context of the entire ecosystem.

Ehrlich, Garth D; Hiller, N Luisa; Hu, Fen Ze

2008-01-01

315

Urban Pigeons ( Columba livia ) as a Potential Source of Pathogenic Yeasts: A Focus on Antifungal Susceptibility of Cryptococcus Strains in Northeast Brazil  

Microsoft Academic Search

To investigate pigeons as a potential source of pathogenic yeast species, 47 samples of pigeon droppings and 322 samples from\\u000a pigeon cloacae were evaluated. The samples were also collected from trees located near the pigeon habitats, in the city of\\u000a Fortaleza, Ceará, Northeast Brazil. In addition, we evaluated the in vitro antifungal susceptibility of these environmental\\u000a Cryptococcus strains to amphotericin

Ana K. F. Costa; José J. C. Sidrim; Rossana A. Cordeiro; Raimunda S. N. Brilhante; André J. Monteiro; Marcos F. G. Rocha

2010-01-01

316

mRNA detection by reverse transcription-PCR for monitoring viability and potential virulence in a pathogenic strain of Vibrio parahaemolyticus in viable but nonculturable state  

Microsoft Academic Search

Aims: This work investigates the maintenance of viability and potential virulence of Vibrio parahaemolyticus in a viable but nonculturable population (VBNC) state by reverse transcription- polymerase chain reaction (RT-PCR). Methods and Results: Housekeeping genes, 16S-23S rDNA and rpoS, as well as virulence genes, tdh1 and tdh2, were selected and detected by PCR in a pathogenic strain of V. parahaemolyticus (Vp4).

F. Coutard; M. Pommepuy; S. Loaec; D. Hervio-Heath

2005-01-01

317

Misdiagnosis of spider bites: bacterial associates, mechanical pathogen transfer, and hemolytic potential of venom from the hobo spider, Tegenaria agrestis (Araneae: Agelenidae).  

PubMed

The European spider Tegenaria agrestis (Walckenaer) (hobo spider) has been implicated as a spider of medical importance in the Pacific Northwest since its introduction in the late 1980s. Studies have indicated that the hobo spider causes necrotic tissue lesions through hemolytic venom or through the transfer of pathogenic bacteria introduced by its bite. Bacterial infections are often diagnosed as spider bites, in particular the pathogenic bacteria methicillin-resistant Staphylococcus aureus (MRSA). This study examines three aspects of the potential medical importance of hobo spiders in part of its introduced range, Washington State. First, the bacterial diversity of the spider was surveyed using a polymerase chain reaction-based assay to determine whether the spider carries any pathogenic bacteria. Second, an experiment was conducted to determine the ability of the spiders to transfer MRSA. Third, the venom was evaluated to assess the hemolytic activity. We found 10 genera of ubiquitous bacteria on the exterior surface of the spiders. In addition, none of the spiders exposed to MRSA transferred this pathogen. Finally, the hemolytic venom assay corroborates previous studies that found hobo spider venom was not deleterious to vertebrate red blood cells. PMID:21485377

Gaver-Wainwright, Melissa M; Zack, Richard S; Foradori, Matthew J; Lavine, Laura Corley

2011-03-01

318

Evaluation of the potential of Trichoderma viride in the control of fungal pathogens of Roselle (Hibiscus sabdariffa L.) in vitro.  

PubMed

The potential of Trichoderma viride as a bio-control agent was evaluated in vitro against Roselle pathogens i.e. Phoma exigua, Fusarium nygamai and Rhizoctonia solani[1] using the dual culture technique. Volatile and non-volatile inhibitors of Trichoderma were also evaluated for this purpose. T. viride[2] was shown to have a marked inhibitory effect on the tested pathogens in vitro. Maximum inhibition occurred against P. exigua, with 71.76% reduction in mycelial radial growth. The three pathogens, P. exigua, F. nygamai and R. solani were also found to be susceptible to the volatile inhibitors produced by T. viride, giving rise to growth inhibition of about 68% in each case. When T. viride non-volatile metabolites were tested against the pathogens, maximum inhibition occurred against R. solani (73.95% mycelial growth inhibition), followed by P. exigua (37.17% inhibition). The inhibitory effect of the non-volatile metabolites on F. nygamai was, however, minimal. PMID:22261114

Eslaminejad Parizi, T; Ansaria, Mehdi; Elaminejad, Tahereh

2012-01-12

319

Antimicrobial susceptibility patterns and sensitivity to tulathromycin in goat respiratory bacterial isolates.  

PubMed

Bacterial pneumonia is a common and often life-threatening respiratory problem in both meat and dairy goats. Options for approved antibiotic therapy in goats to combat these bacterial infections are severely limited and frequently drugs must be used in an extra-label manner. Tulathromycin, a triamilide macrolide antimicrobial drug shown to be effective against swine and cattle respiratory bacterial agents, has been identified as a potentially useful drug in caprines. The present study was conducted to determine the susceptibility of recognized bacterial respiratory pathogens to commonly prescribed antimicrobials, with a particular emphasis on the efficacy of tulathromycin against these agents. Minimum inhibitory concentration (MIC) testing using microbroth dilution was performed on a collection of 45 Mannheimia haemolytica, 11 Pasteurella multocida, and 11 Bibersteinia trehalosi isolates from the lungs of goats with clinical pneumonia. To further characterize efficacy of tulathromycin against these pathogens, minimum bactericidal concentration (MBC) testing and kinetic killing assays were conducted. Most isolates were susceptible to the antimicrobials tested; however, increased resistance as demonstrated by higher MIC values was seen in all species to penicillin, in P. multocida to sulfadimethoxine, and in B. trehalosi to the tetracyclines. All isolates were susceptible to tulathromycin, which demonstrated a high killing efficiency in both bactericidal assays. Results of this study indicate that most goat pneumonic bacterial pathogens remain susceptible to commonly prescribed antibiotics, although some evidence of resistance was seen to certain drugs; and that tulathromycin is highly effective against goat respiratory pathogens which could make it a valuable medication in this species. PMID:22078276

Clothier, Kristin A; Kinyon, Joann M; Griffith, Ronald W

2011-10-25

320

Range-wide genetic population structure of common pochard (Aythya ferina): a potentially important vector of highly pathogenic avian influenza viruses  

PubMed Central

An understanding of the distribution and spatial structure of the natural vectors of zoonothic pathogens is of interest for effective disease control and prevention. Here, we investigate the range-wide population genetic structure of common pochard (Aythya ferina), a long-distance migratory duck and potential vector of highly pathogenic avian influenza. We collected several hundred samples from breeding and wintering grounds across Eurasia including some H5N1-positive individuals and generated partial sequences of the mitochondrial control region and multilocus microsatellite genotypes. Genetic differentiation among breeding populations was significant for both marker types but higher for maternally inherited mtDNA than for biparentally inherited nuclear markers. There was only weak genetic divergence between ducks sampled in Europe and East Asia, and genetic differentiation between populations was not generally associated with geographical distance. No evidence of genetic substructure was detected for ducks sampled on the European wintering grounds. Our results suggest limited breeding-site fidelity, especially in females, but extensive population admixture on the wintering grounds. The specific role of pochards as natural vectors of zoonotic pathogens and in particular H5N1 remains to be clarified but our results point to wintering grounds as potential hotspots for disease transmission.

Liu, Yang; Keller, Irene; Heckel, Gerald

2011-01-01

321

Identification and characterization of potential therapeutic candidates in emerging human pathogen Mycobacterium abscessus: a novel hierarchical in silico approach.  

PubMed

Mycobacterium abscessus, a non-tuberculous rapidly growing mycobacterium, is recognized as an emerging human pathogen causing a variety of infections ranging from skin and soft tissue infections to severe pulmonary infections. Lack of an optimal treatment regimen and emergence of multi-drug resistance in clinical isolates necessitate the development of better/new drugs against this pathogen. The present study aims at identification and qualitative characterization of promising drug targets in M. abscessus using a novel hierarchical in silico approach, encompassing three phases of analyses. In phase I, five sets of proteins were mined through chokepoint, plasmid, pathway, virulence factors, and resistance genes and protein network analysis. These were filtered in phase II, in order to find out promising drug target candidates through subtractive channel of analysis. The analysis resulted in 40 therapeutic candidates which are likely to be essential for the survival of the pathogen and non-homologous to host, human anti-targets, and gut flora. Many of the identified targets were found to be involved in different metabolisms (viz., amino acid, energy, carbohydrate, fatty acid, and nucleotide), xenobiotics degradation, and bacterial pathogenicity. Finally, in phase III, the candidate targets were qualitatively characterized through cellular localization, broad spectrum, interactome, functionality, and druggability analysis. The study explained their subcellular location identifying drug/vaccine targets, possibility of being broad spectrum target candidate, functional association with metabolically interacting proteins, cellular function (if hypothetical), and finally, druggable property. Outcome of the present study could facilitate the identification of novel antibacterial agents for better treatment of M. abscesses infections. PMID:23527108

Shanmugham, Buvaneswari; Pan, Archana

2013-03-19

322

The adaptive potential of a plant pathogenic fungus, Rhizoctonia solani AG3, under heat and fungicide stress  

Microsoft Academic Search

The ability to improve fitness via adaptive evolution may be affected by environmental change. We tested this hypothesis in\\u000a 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\\u000a optimal) and three fungicide concentrations (no fungicide, low and high concentration of a copper-based fungicide).

Yvonne Willi; Aline Frank; Renate Heinzelmann; Andrea Kälin; Lena Spalinger; Paulo C. Ceresini

2011-01-01

323

Potential Pathogenicity and Host Range of Extended-Spectrum ?-Lactamase-Producing Escherichia coli Isolates from Healthy Poultry ?  

PubMed Central

Thirty of 33 epidemiologically unrelated extended-spectrum ?-lactamase (ESBL)-producing Escherichia coli isolates from healthy poultry lacked the virulence genes commonly associated with human-pathogenic strains. The main zoonotic risk is associated with the broad host range of avian E. coli belonging to sequence type complex 10 and of IncN and IncI1 plasmids carrying blaCTX-M or blaSHV.

Bortolaia, Valeria; Larsen, Jesper; Damborg, Peter; Guardabassi, Luca

2011-01-01

324

Vermistabilization of sewage sludge (biosolids) by earthworms: converting a potential biohazard destined for landfill disposal into a pathogen-free, nutritive and safe biofertilizer for farms.  

PubMed

Earthworms feed readily upon sludge components, rapidly converting them into vermicompost, reduce the pathogens to safe levels and ingest the heavy metals. Volume is significantly reduced from 1 m³ of wet sludge (80% moisture) to 0.5 m³ of vermicompost (30% moisture). Earthworms have real potential both to increase the rate of aerobic decomposition and composting of organic matter and also to stabilize the organic residues in the sludge--removing the harmful pathogens (by devouring them and also by discharge of antibacterial coelomic fluid) and heavy metals (by bio-accumulation). They also mineralize the essential nutrients nitrogen, phosphorus and potassium from the sludge. It may not be possible to remove toxic substances completely, but at least change the 'chemical make-up' of the sludge to make it harmless to the soil and enable its use as a nutritive organic fertilizer. This method has been found to comply with grade A standards for sludge stabilization. PMID:19710116

Sinha, Rajiv K; Herat, Sunil; Bharambe, Gokul; Brahambhatt, Ashish

2009-08-26

325

The Challenge of Respiratory Virus Infections in Hematopoietic Cell Transplant Recipients  

PubMed Central

Respiratory virus infections in hematopoietic cell transplant (HCT) recipients are a major cause of morbidity and mortality. While respiratory syncytial virus (RSV), human metapneumonvirus, parainfluenzaviruses, and influenza viruses are well known for their potential to cause fatal pneumonia, information is emerging only recently on the significance of the newly discovered viruses such as human coronaviruses NL63 and HKU1, and human bocavirus. Lymphopenia seems to be the most recent risk factors for progression to lower respiratory tract disease. Airflow obstruction is another complication of respiratory virus infections after HCT, and data to date indicate this complication may occur following parainfluenza virus and RSV infection. Infection control procedures are key for prevention. Unfortunately, there are no randomized treatment studies, which make the interpretation of the literature on interventions difficult. This article reviews the spectrum of pathogens, epidemiology, risk factors and clinical manifestations of infection, as well as recent advances in diagnostic and clinical management.

Boeckh, Michael

2009-01-01

326

Cytotoxic responses and potential respiratory health effects of carbon and carbonaceous nanoparticulates in the Paso del Norte airshed environment.  

PubMed

We have utilized a range of manufactured or commercial nanoparticulate materials, including surrogate carbon nano-PM along with combustion-generated carbonaceous (soot) nano-PM characteristic of environmental nano- PM (both indoor and outdoor) to investigate and compare their cytotoxic response in vitro with an immortalized human epithelial (lung model) cell line (A549). These have included nano-Ag, Al2O3, TiO2, Fe2O3, ZrO2, Si3N4, chrysotile asbestos, BC, 2 types of MWCNT-aggregate PM (MWCNT-R and MWCNT-N), and high-volume glass fiber collected soots: candle, wood, diesel (truck), tire, and 3-types of natural gas kitchen burner-generated soots: yellow (fuel-rich) flame, low-flow blue flame, and normal flow blue flame soot PM. These carbonaceous nano-PM species can be found in either the indoor and outdoor environments or microenvironments. Two-day and two-week in-vitro cultures of A549 showed cell death (or decreased cell viability) for all nanoparticulate materials, but especially significant for all but the TiO2 and candle, wood, and diesel PM. The natural gas kitchen burner combustion PM cell death response was characteristic of BC and MWCNT PM. There was no correlation with total PAH content of the soot PM. Cytokine release (IL-6, IL-8) was detected for the Ag, Fe2 O3, asbestos, BC and the MWCNT PM. Reactive oxygen species (ROS) production was also detected for Ag, Fe2 O3, ZrO2, asbestos, BC, and the MWCNT aggregate PM, as well as the natural gas kitchen burner combustion PM. TEM, FESEM, and optical microscopy examination of these nanomaterials illustrate the wide range in PM morphologies and crystallinities as well as cell morphologies. Taken together, these results illustrate proinflammatory and related respiratory health issues in relation to environmental nanoparticulates. PMID:18441401

Soto, K F; Murr, L E; Garza, K M

2008-03-01

327

Pathogens: raft hijackers  

Microsoft Academic Search

Throughout evolution, organisms have developed immune-surveillance networks to protect themselves from potential pathogens. At the cellular level, the signalling events that regulate these defensive responses take place in membrane rafts — dynamic microdomains that are enriched in cholesterol and glycosphingolipids — that facilitate many protein–protein and lipid–protein interactions at the cell surface. Pathogens have evolved many strategies to ensure their

Santos Mañes; Gustavo del Real; Carlos Martínez-A

2003-01-01

328

Pathogenic Microorganisms in Water  

NSDL National Science Digital Library

Pathogenic Microorganisms in Water: Traditionally, groundwater has been used without treatment because the soil acts as a filter, removing pathogenic microorganisms. Some potential sources of pathogens (or disease causing organisms) in groundwater include septic tanks, leaking sewer lines, sewage sludge, intentional groundwater recharge with sewage, irrigation with sewage, direct injection of sewage, domestic solid waste disposal (landfills) and sewage oxidation ponds. The objective of the session is to introduce hydrogeologist to the types of microorganisms, sources of pathogens, and a simple exercise that can be incorporated into a hydrogeology class.

Lenczewski, Melissa

329

Respiratory Therapists  

MedlinePLUS

... or emphysema. They also provide emergency care to patients suffering from heart attacks, stroke, drowning, or shock. Work Environment Most respiratory therapists work in hospitals. Others may work in nursing care facilities or travel to patients’ homes. How to ...

330

Respiratory System  

NSDL National Science Digital Library

The purpose, components, and functions of the respiratory system are presented in this learning through disussion and visualizations. Participants learn about the nasal cavity, pharynx, larynx, trachea, bronchi, bronchioles, and alveoli.

Bidlack, Jim

331

Waterborne human pathogenic viruses of public health concern.  

PubMed

In recent years, the impending impact of waterborne pathogens on human health has become a growing concern. Drinking water and recreational exposure to polluted water have shown to be linked to viral infections, since viruses are shed in extremely high numbers in the faeces and vomit of infected individuals and are routinely introduced into the water environment. All of the identified pathogenic viruses that pose a significant public health threat in the water environment are transmitted via the faecal-oral route. This group, are collectively known as enteric viruses, and their possible health effects include gastroenteritis, paralysis, meningitis, hepatitis, respiratory illness and diarrhoea. This review addresses both past and recent investigations into viral contamination of surface waters, with emphasis on six types of potential waterborne human pathogenic viruses. In addition, the viral associated illnesses are outlined with reference to their pathogenesis and routes of transmission. PMID:23432800

Ganesh, Atheesha; Lin, Johnson

2013-02-22

332

Transplantation-associated long-term immunosuppression promotes oral colonization by potentially opportunistic pathogens without impacting other members of the salivary bacteriome.  

PubMed

Solid-organ transplant recipients rely on pharmacological immunosuppression to prevent allograft rejection. The effect of such chronic immunosuppression on the microflora at mucosal surfaces is not known. We evaluated the salivary bacterial microbiome of 20 transplant recipients and 19 nonimmunosuppressed controls via 454 pyrosequencing of 16S rRNA gene amplicons. Alpha-diversity and global community structure did not differ between transplant and control subjects. However, principal coordinate analysis showed differences in community membership. Taxa more prevalent in transplant subjects included operational taxonomic units (OTUs) of potentially opportunistic Gammaproteobacteria such as Klebsiella pneumoniae, Pseudomonas fluorescens, Acinetobacter species, Vibrio species, Enterobacteriaceae species, and the genera Acinetobacter and Klebsiella. Transplant subjects also had increased proportions of Pseudomonas aeruginosa, Acinetobacter species, Enterobacteriaceae species, and Enterococcus faecalis, among other OTUs, while genera with increased proportions included Klebsiella, Acinetobacter, Staphylococcus, and Enterococcus. Furthermore, in transplant subjects, the dose of the immunosuppressant prednisone positively correlated with bacterial richness, while prednisone and mycophenolate mofetil doses positively correlated with the prevalence and proportions of transplant-associated taxa. Correlation network analysis of OTU relative abundance revealed a cluster containing potentially opportunistic pathogens as transplant associated. This cluster positively correlated with serum levels of C-reactive protein, suggesting a link between the resident flora at mucosal compartments and systemic inflammation. Network connectivity analysis revealed opportunistic pathogens as highly connected to each other and to common oral commensals, pointing to bacterial interactions that may influence colonization. This work demonstrates that immunosuppression aimed at limiting T-cell-mediated responses creates a more permissive oral environment for potentially opportunistic pathogens without affecting other members of the salivary bacteriome. PMID:23616410

Diaz, Patricia I; Hong, Bo-Young; Frias-Lopez, Jorge; Dupuy, Amanda K; Angeloni, Mark; Abusleme, Loreto; Terzi, Evimaria; Ioannidou, Effie; Strausbaugh, Linda D; Dongari-Bagtzoglou, Anna

2013-04-24

333

Botryosphaeriaceae as potential pathogens of prunus species in South Africa, with descriptions of Diplodia africana and Lasiodiplodia plurivora sp. nov.  

PubMed

Botryosphaeriaceae are common dieback and canker pathogens of woody host plants, including stone fruit trees. In the present study the diversity of members of the Botryosphaeriaceae isolated from symptomatic wood of Prunus species (plum, peach, nectarine and apricot) was determined in stone fruit-growing areas in South Africa. Morphological and cultural characteristics as well as DNA sequence data (5.8S rDNA, ITS-1, ITS-2 and EF-1a) were used to identify known members and describe novel members of Botryosphaeriaceae. From the total number of wood samples collected (258) 67 isolates of Botryosphaeriaceae were obtained, from which eight species were identified. All species were associated with wood necrosis. Diplodia seriata (= "Botryosphaeria" obtusa) was dominant, and present on all four Prunus species sampled, followed by Neofusicoccum vitifusiforme and N. australe. First reports from Prunus spp. include N. vitifusiforme, Dothiorella viticola and Diplodia pinea. This is also the first report of D. mutila from South Africa. Two species are newly described, namely Lasiodiplodia plurivora sp. nov. from P. salicina and Diplodia africana sp. nov. from P. persica. All species, except Dothiorella viticola, caused lesions on green nectarine and/or plum shoots in a detached shoot pathogenicity assay. PMID:18268901

Damm, Ulrike; Crous, Pedro W; Fourie, Paul H

334

METHODOLOGY TO APPORTION AMBIENT AIR MEASUREMENTS TO INVESTIGATE POTENTIAL SHORT-TERM RESPIRATORY EFFECTS NEAR WASTE INCINERATORS  

EPA Science Inventory

Ambient air samples at four sites located near two incinerators (a biomedical waste and a municipal incinerator) in the vicinity of Charlotte, North Carolina were acquired as part of a health effects study that is examining potential, short-term, lung dysfunctions associated with...

335

An endophytic/pathogenic Phoma sp. from creosote bush producing biologically active volatile compounds having fuel potential.  

PubMed

A Phoma sp. was isolated and characterized as endophytic and as a pathogen of Larrea tridentata (creosote bush) growing in the desert region of southern Utah, USA. This fungus produces a unique mixture of volatile organic compounds (VOCs), including a series of sesquiterpenoids, some alcohols and several reduced naphthalene derivatives. Trans-caryophyllene, a product in the fungal VOCs, was also noted in the VOCs of this pungent plant. The gases of Phoma sp. possess antifungal properties and is markedly similar to that of a methanolic extract of the host plant. Some of the test organisms with the greatest sensitivity to the Phoma sp. VOCs were Verticillium, Ceratocystis, Cercospora and Sclerotinia while those being the least sensitive were Trichoderma, Colletotrichum and Aspergillus. We discuss the possible involvement of VOC production by the fungus and its role in the biology/ecology of the fungus/plant/environmental relationship with implications for utilization as an energy source. PMID:21535100

Strobel, Gary; Singh, Sanjay K; Riyaz-Ul-Hassan, Syed; Mitchell, Angela M; Geary, Brad; Sears, Joe

2011-05-20

336

Basic microbiologic and infection control information to reduce the potential transmission of pathogens to patients via computer hardware.  

PubMed

Computer technology from the management of individual patient medical records to the tracking of epidemiologic trends has become an essential part of all aspects of modern medicine. Consequently, computers, including bedside components, point-of-care testing equipment, and handheld computer devices, are increasingly present in patients' rooms. Recent articles have indicated that computer hardware, just as other medical equipment, may act as a reservoir for microorganisms and contribute to the transfer of pathogens to patients. This article presents basic microbiological concepts relative to infection, reviews the present literature concerning possible links between computer contamination and nosocomial colonizations and infections, discusses basic principles for the control of contamination, and provides guidelines for reducing the risk of transfer of microorganisms to susceptible patient populations. PMID:12223502

Neely, Alice N; Sittig, Dean F

337

Population Abundance of Potentially Pathogenic Organisms in Intestinal Microbiome of Jungle Crow (Corvus macrorhynchos) Shown with 16S rRNA Gene-Based Microbial Community Analysis  

PubMed Central

Jungle Crows (Corvus macrorhynchos) prefer human habitats because of their versatility in feeding accompanied with human food consumption. Therefore, it is important from a public health viewpoint to characterize their intestinal microbiota. However, no studies have been involved in molecular characterization of the microbiota based on huge and reliable number of data acquisition. In this study, 16S rRNA gene-based microbial community analysis coupled with the next-generation DNA sequencing techniques was applied to the taxonomic classification of intestinal microbiome for three jungle crows. Clustering of the reads into 130 operational taxonomic units showed that at least 70% of analyzed sequences for each crow were highly homologous to Eimeria sp., which belongs to the protozoan phylum Apicomplexa. The microbiotas of three crows also contained potentially pathogenic bacteria with significant percentages, such as the genera Campylobacter and Brachyspira. Thus, the profiling of a large number of 16S rRNA gene sequences in crow intestinal microbiomes revealed the high-frequency existence or vestige of potentially pathogenic microorganisms.

Maeda, Isamu; Siddiki, Mohammad Shohel Rana; Nozawa-Takeda, Tsutomu; Tsukahara, Naoki; Tani, Yuri; Naito, Taki; Sugita, Shoei

2013-01-01

338

Respiratory Hydrogen Use by Salmonella enterica Serovar Typhimurium Is Essential for Virulence  

Microsoft Academic Search

Based on available annotated gene sequence information, the enteric pathogen salmonella, like other enteric bacteria, contains three putative membrane-associated H2-using hydrogenase enzymes. These enzymes split molecular H2, releasing low-potential electrons that are used to reduce quinone or heme-containing compo- nents of the respiratory chain. Here we show that each of the three distinct membrane-associated hydrogenases of Salmonella enterica serovar Typhimurium

R. J. Maier; A. Olczak; S. Maier; S. Soni; J. Gunn

2004-01-01

339

High rate of Simkania negevensis among Canadian inuit infants hospitalized with lower respiratory tract infections.  

PubMed

To determine the prevalence of Simkania negevensis in causing pulmonary infections in children, nasopharyngeal washes were obtained from 22 infants hospitalized with acute bronchiolitis in the Baffin Island, Canada. 14 (63.6%) were positive for S. negevensis. Mixed infections with other respiratory viruses were common. All patients recovered without specific antibiotic treatment. Even though a high prevalence of S. negevensis was found, this organism may potentially well be an opportunistic agent rather than a true pathogen. PMID:14514154

Greenberg, David; Banerji, Anna; Friedman, Maureen G; Chiu, Cheng-Hsun; Kahane, Simona

2003-01-01

340

Investigation into sampling strategies in response to potential outbreaks of low pathogenicity notifiable avian influenza initiated in commercial duck holdings in Great Britain.  

PubMed

The aim of this study was to evaluate potential sampling strategies for detection of infected flocks that could be applied during an outbreak of low pathogenicity notifiable avian influenza (LPNAI) initiated in duck holdings, following initial detection. A simulation model of avian influenza virus transmission and spread within and between holdings, respectively, was used to predict the impact on the size and duration of an outbreak of (i) changing the tracing window within which premises that might be the source of infection or that may have been infected by the index premises were sampled and (ii) changing the number of birds sampled in the flock being tested. It has shown that there is potential benefit in increasing the tracing window in terms of reducing the likelihood of a large outbreak. It has also shown that there is comparatively little benefit from increasing the number of birds sampled per flock. PMID:22793646

Arnold, M E; Irvine, R M; Tearne, O; Rae, D; Cook, A J C; Breed, A C

2012-07-16

341

Neurogenic respiratory failure.  

PubMed

It is uncommon for the lungs to be primarily involved in neurological conditions but severe respiratory problems can arise indirectly. These are usually the result of disorders of central ventilatory control, respiratory muscle weakness, or bulbar involvement. The effects of those disorders can be predicted by an understanding of the nervous control mechanisms and mechanical factors that determine effective ventilation. Awareness of these potential complications, and the increased availability of more advanced diagnostic and monitoring techniques in everyday clinical practice, has resulted in the introduction of specific treatments to try to reduce consequent morbidity and mortality. PMID:23312649

Hind, Charles R K

2013-01-01

342

History of U.S. military contributions to the study of respiratory infections.  

PubMed

History reveals a tremendous impact of respiratory pathogens on the U.S. military, dating back to the time of the Revolutionary and Civil Wars, during which 90% of casualties were for nonbattle injury, including several respiratory illnesses such as measles, whooping cough, and complicated pneumonia. The devastating impact of the influenza pandemic at the end of World War I led to a more proactive approach to research into the etiologies and potential preventive measures for such diseases. The development of the Armed Forces Epidemiological Board, with its subordinate commissions, coincided with the massive mobilization for World War II. Efforts of the board during and after the war led to significant progress against many common pathogens, such as the landmark studies of group A Streptococcus among young trainees at Warren Air Force Base, which led to the development of highly effective prophylactic and therapeutic strategies to prevent rheumatic fever. Military pediatricians contributed greatly to this work, as well as subsequent investigations into both the pathogenesis of and prophylactic therapy for a variety respiratory pathogens, including pertussis and respiratory syncytial virus. The momentum of this work continues to this day, among researchers from all three military branches. PMID:15916285

Ottolini, Martin G; Burnett, Mark W

2005-04-01

343

Evaluation of potential reference genes for use in gene expression studies in the conifer pathogen (Heterobasidion annosum).  

PubMed

The basidiomycete Heterobasidion annosum is the causative agent of butt and root rot disease of conifer trees and it's one of the most destructive conifer pathogen in the northern hemisphere. Because of the intrinsic difficulties in genome manipulation in this fungus, most studies have been focused on gene expression analysis using quantitative real time polymerase chain reaction (qPCR). qPCR is a powerful technique but its reliability resides in the correct selection of a set of reference genes used in the data normalization. In this study, we determined the expression stability of 11 selected reference genes in H. annosum. Almost nothing has so far been published about validation of a set of reference genes to be used in gene expression experiments in this fungus. Eleven reference genes were validated in H. annosum which was grown on three different substrates: pine bark, pine heartwood, and pine sapwood. Bestkeeper and NormFinder Excel-based software were used to evaluate the reference gene transcripts' stability. The results from these two programs indicated that three reference genes namely Tryp metab, RNA Pol3 TF, and Actin were stable in H. annosum in the conditions studied. Interestingly, the GAPDH transcript which has been extensively used in qPCR data normalization is not the best choice when a wide reference gene selection is available. This work represents the first extensive validation of reference genes in H. annosum providing support for gene expression studies and benefits for the wider forest pathology community. PMID:23645035

Raffaello, Tommaso; Asiegbu, Fred O

2013-05-05

344

Potential pathogenic properties of members of the "Streptococcus milleri" group in relation to the production of endocarditis and abscesses.  

PubMed

The "Streptococcus milleri" (SMG) group have been shown to possess factors in vitro that may be involved in pathogenesis. All SMG strains are able to bind fibronectin via a cell-surface protein; the binding ranged from 12 to 198 mol/cell. Strains also bound to platelet-fibrin or fibrin clots and fibrinogen, giving maximum adhesion values of 16.5%, 21.8% and 151 mol/cell respectively. Members of the species S. constellatus produced thrombin-like activity. Lancefield group C SMG aggregated rat platelets, a bacterial cell-surface protein acting as mediator in the reaction. Most of the in-vitro factors did not correlate with each other, an indication that SMG strains possess a wide variety of pathogenic properties that may be involved in the production of abscesses or endocarditis. However, there was a correlation between the binding of large amounts of fibrinogen ( > 100 mol/cell) and the ability to aggregate platelets. This suggests that fibrinogen binding may aid in platelet aggregation. PMID:7473673

Willcox, M D

1995-12-01

345

Use of Zebrafish to Probe the Divergent Virulence Potentials and Toxin Requirements of Extraintestinal Pathogenic Escherichia coli  

PubMed Central

Extraintestinal pathogenic E. coli (ExPEC) cause an array of diseases, including sepsis, neonatal meningitis, and urinary tract infections. Many putative virulence factors that might modulate ExPEC pathogenesis have been identified through sequencing efforts, epidemiology, and gene expression profiling, but few of these genes have been assigned clearly defined functional roles during infection. Using zebrafish embryos as surrogate hosts, we have developed a model system with the ability to resolve diverse virulence phenotypes and niche-specific restrictions among closely related ExPEC isolates during either localized or systemic infections. In side-by-side comparisons of prototypic ExPEC isolates, we observed an unexpectedly high degree of phenotypic diversity that is not readily apparent using more traditional animal hosts. In particular, the capacity of different ExPEC isolates to persist and multiply within the zebrafish host and cause disease was shown to be variably dependent upon two secreted toxins, ?-hemolysin and cytotoxic necrotizing factor. Both of these toxins appear to function primarily in the neutralization of phagocytes, which are recruited in high numbers to sites of infection where they act as an essential host defense against ExPEC as well as less virulent E. coli strains. These results establish zebrafish as a valuable tool for the elucidation and functional analysis of both ExPEC virulence factors and host defense mechanisms.

Wiles, Travis J.; Bower, Jean M.; Redd, Michael J.; Mulvey, Matthew A.

2009-01-01

346

Elaboration of highly hydrophobic polymeric surface--a potential strategy to reduce the adhesion of pathogenic bacteria?  

PubMed

Different polymeric surfaces have been modified in order to reach a high hydrophobic character, indeed the superhydrophobicity property. For this purpose, polypropylene and polystyrene have been treated by RF or ?waves CF4 plasma with different volumes, the results were compared according to the density of injected power. The effect of pretreatment such as mechanical abrasion or plasma activation was also studied. The modified surfaces were shown as hydrophobic, or even superhydrophobic depending of defects density. They were characterized by measurement of wettability and roughness at different scales, i.e. macroscopic, mesoscopic and atomic. It has been shown that a homogeneous surface at the macroscopic scale could be heterogeneous at lower mesoscopic scale. This was associated with the crystallinity of the material. The bioadhesion tests were performed with Gram positive and negative pathogenic strains: Listeria monocytogenes, Pseudomonas aeruginosa and Hafnia alvei. They have demonstrated an antibacterial efficiency of very hydrophobic and amorphous PS treated for all strains tested and a strain-dependent efficiency with modified PP surface being very heterogeneous at the mesoscopic scale. Thus, these biological results pointed out not only the respective role of the surface chemistry and topography in bacterial adhesion, but also the dependence on the peaks and valley distribution at bacteria dimension scale. PMID:23827554

Poncin-Epaillard, F; Herry, J M; Marmey, P; Legeay, G; Debarnot, D; Bellon-Fontaine, M N

2012-12-11

347

Chinchilla and Murine Models of Upper Respiratory Tract Infections with Respiratory Syncytial Virus  

PubMed Central

Respiratory syncytial virus (RSV) is a major cause of lower respiratory tract infections in infants and the elderly. While the primary infection is the most serious, reinfection of the upper airway throughout life is the rule. Although relatively little is known about either RSV infection of the upper respiratory tract or host mucosal immunity to RSV, recent literature suggests that RSV is the predominant viral pathogen predisposing to bacterial otitis media (OM). Herein, we describe mouse and chinchilla models of RSV infection of the nasopharynx and Eustachian tube. Both rodent hosts were susceptible to RSV infection of the upper airway following intranasal challenge; however, the chinchilla proved to be more permissive than the mouse. The chinchilla model will likely be extremely useful to test the role of RSV in bacterial OM and the efficacy of RSV vaccine candidates designed to provide mucosal and cytotoxic T-lymphocyte immunity. Ultimately, we hope to investigate the relative ability of these candidates to potentially protect against viral predisposal to bacterial OM.

Gitiban, Negin; Jurcisek, Joseph A.; Harris, Randall H.; Mertz, Sara E.; Durbin, Russell K.; Bakaletz, Lauren O.; Durbin, Joan E.

2005-01-01

348

Attenuated and replication-competent vaccinia virus strains M65 and M101 with distinct biology and immunogenicity as potential vaccine candidates against pathogens.  

PubMed

Replication-competent poxvirus vectors with an attenuation phenotype and with a high immunogenic capacity of the foreign expressed antigen are being pursued as novel vaccine vectors against different pathogens. In this investigation, we have examined the replication and immunogenic characteristics of two vaccinia virus (VACV) mutants, M65 and M101. These mutants were generated after 65 and 101 serial passages of persistently infected Friend erythroleukemia (FEL) cells. In cultured cells of different origins, the mutants are replication competent and have growth kinetics similar to or slightly reduced in comparison with those of the parental Western Reserve (WR) virus strain. In normal and immune-suppressed infected mice, the mutants showed different levels of attenuation and pathogenicity in comparison with WR and modified vaccinia Ankara (MVA) strains. Wide genome analysis after deep sequencing revealed selected genomic deletions and mutations in a number of viral open reading frames (ORFs). Mice immunized in a DNA prime/mutant boost regimen with viral vectors expressing the LACK (Leishmania homologue for receptors of activated C kinase) antigen of Leishmania infantum showed protection or a delay in the onset of cutaneous leishmaniasis. Protection was similar to that triggered by MVA-LACK. In immunized mice, both polyfunctional CD4(+) and CD8(+) T cells with an effector memory phenotype were activated by the two mutants, but the DNA-LACK/M65-LACK protocol preferentially induced CD4(+) whereas DNA-LACK/M101-LACK preferentially induced CD8(+) T cell responses. Altogether, our findings showed the adaptive changes of the WR genome during long-term virus-host cell interaction and how the replication competency of M65 and M101 mutants confers distinct biological properties and immunogenicity in mice compared to those of the MVA strain. These mutants could have applicability for understanding VACV biology and as potential vaccine vectors against pathogens and tumors. PMID:23596295

Sánchez-Sampedro, Lucas; Gómez, Carmen Elena; Mejías-Pérez, Ernesto; Pérez-Jiménez, Eva; Oliveros, Juan Carlos; Esteban, Mariano

2013-04-17

349

Respiratory System  

MedlinePLUS

... Search Form Advanced Search Search the NHLBI, use radio buttons below to select whole site or Disease and Conditions Index only NHLBI Entire ... Information for the Public » Health Topics » How the Lungs Work » The Respiratory System How the Lungs Work Explore ...

350

Cytokine Production from Peripheral Blood Mononuclear Cells of Mite Allergen-Sensitized Atopic Adults Stimulated with Respiratory Syncytial Virus and Mite Allergen  

Microsoft Academic Search

Background: The interaction between viral respiratory tract infection and allergen sensitization in allergic asthma is unclear. Respiratory syncytial virus (RSV) has attracted attention as an important lower respiratory pathogen during childhood, while recent evidence indicates that RSV is also an important lower respiratory pathogen for adults. Immunity against RSV differs between children and adults. Several reports suggest that RSV infection

Hiroko Hirose; Hiroto Matsuse; Tomoko Tsuchida; Susumu Fukahori; Chizu Fukushima; Yohei Mizuta; Shigeru Kohno

2008-01-01

351

Effect of Ethanol on Differential Protein Production and Expression of Potential Virulence Functions in the Opportunistic Pathogen Acinetobacter baumannii  

PubMed Central

Acinetobacter baumannii persists in the medical environment and causes severe human nosocomial infections. Previous studies showed that low-level ethanol exposure increases the virulence of A. baumannii ATCC 17978. To better understand the mechanisms involved in this response, 2-D gel electrophoresis combined with mass spectrometry was used to investigate differential protein production in bacteria cultured in the presence or absence of ethanol. This approach showed that the presence of ethanol significantly induces and represses the production of 22 and 12 proteins, respectively. Although over 25% of the ethanol-induced proteins were stress-response related, the overall bacterial viability was uncompromised when cultured under these conditions. Production of proteins involved in lipid and carbohydrate anabolism was increased in the presence of ethanol, a response that correlates with increased carbohydrate biofilm content, enhanced biofilm formation on abiotic surfaces and decrease bacterial motility on semi-solid surfaces. The presence of ethanol also induced the acidification of bacterial cultures and the production of indole-3-acetic acid (IAA), a ubiquitous plant hormone that signals bacterial stress-tolerance and promotes plant-bacteria interactions. These responses could be responsible for the significantly enhanced virulence of A. baumannii ATCC 17978 cells cultured in the presence of ethanol when tested with the Galleria mellonella experimental infection model. Taken together, these observations provide new insights into the effect of ethanol in bacterial virulence. This alcohol predisposes the human host to infections by A. baumannii and could favor the survival and adaptation of this pathogen to medical settings and adverse host environments.

Nwugo, Chika C.; Arivett, Brock A.; Zimbler, Daniel L.; Gaddy, Jennifer A.; Richards, Ashley M.; Actis, Luis A.

2012-01-01

352

Chlorophyll a might structure a community of potentially pathogenic culturable Vibrionaceae. Insights from a one-year study of water and mussels surveyed on the French Atlantic coast.  

PubMed

The present study focused on the isolation of culturable bacteria from mussels and sea water to identify Vibrionaceae potentially pathogenic for humans. Three sites located on the French Atlantic coast were monitored monthly (twice each month during summer) for 1 year. Environmental parameters were surveyed (water temperature, salinity, turbidity, chlorophyll a) and bacteria were detected by culture and identified by API 20E(®) systems (BioMérieux) and PCR. A total of seven species were detected (Grimontia hollisae, Photobacterium damselae, Vibrio alginolyticus, V. cholerae, V. fluvialis, V. vulnificus and V. parahaemolyticus) and species diversity was higher at the end of summer. Surprisingly, V. cholerae non-O1/non-O139 was detected in spring. No site effect was detected. Using Sørensen similarity indices and statistical analyses, we showed that chlorophyll a had a significant influence on the bacterial community detected in mussels and assemblages were more similar to one another when chlorophyll a values were above 20?µg?l(-1) . No significant effect of any parameter was found on the community detected in water samples. Such surveys are essential for the understanding of sanitary crises and detection of emerging pathogens. PMID:23766015

Deter, J; Lozach, S; Derrien, A; Véron, A; Chollet, J; Hervio-Heath, D

2010-02-01

353

Vitamin D and respiratory health  

PubMed Central

Vitamin D is now known to be of physiological importance outside of bone health and calcium homeostasis, and there is mounting evidence that it plays a beneficial role in the prevention and/or treatment of a wide range of diseases. In this brief review the known effects of vitamin D on immune function are described in relation to respiratory health. Vitamin D appears capable of inhibiting pulmonary inflammatory responses while enhancing innate defence mechanisms against respiratory pathogens. Population-based studies showing an association between circulating vitamin D levels and lung function provide strong justification for randomized controlled clinical trials of vitamin D supplementation in patients with respiratory diseases to assess both efficacy and optimal dosage.

Hughes, D A; Norton, R

2009-01-01

354

Potential spread of highly pathogenic avian influenza H5N1 by wildfowl: dispersal ranges and rates determined from large-scale satellite telemetry  

USGS Publications Warehouse

1. Migratory birds are major candidates for long-distance dispersal of zoonotic pathogens. In recent years, wildfowl have been suspected of contributing to the rapid geographic spread of the highly pathogenic avian influenza (HPAI) H5N1 virus. Experimental infection studies reveal that some wild ducks, geese and swans shed this virus asymptomatically and hence have the potential to spread it as they move. 2. We evaluate the dispersive potential of HPAI H5N1 viruses by wildfowl through an analysis of the movement range and movement rate of birds monitored by satellite telemetry in relation to the apparent asymptomatic infection duration (AID) measured in experimental studies. We analysed the first large-scale data set of wildfowl movements, including 228 birds from 19 species monitored by satellite telemetry in 2006–2009, over HPAI H5N1 affected regions of Asia, Europe and Africa. 3. Our results indicate that individual migratory wildfowl have the potential to disperse HPAI H5N1 over extensive distances, being able to perform movements of up to 2900 km within timeframes compatible with the duration of asymptomatic infection. 4. However, the likelihood of such virus dispersal over long distances by individual wildfowl is low: we estimate that for an individual migratory bird there are, on average, only 5–15 days per year when infection could result in the dispersal of HPAI H5N1 virus over 500 km. 5. Staging at stopover sites during migration is typically longer than the period of infection and viral shedding, preventing birds from dispersing a virus over several consecutive but interrupted long-distance movements. Intercontinental virus dispersion would therefore probably require relay transmission between a series of successively infected migratory birds. 6. Synthesis and applications. Our results provide a detailed quantitative assessment of the dispersive potential of HPAI H5N1 virus by selected migratory birds. Such dispersive potential rests on the assumption that free-living wildfowl will respond analogously to captive, experimentally-infected birds, and that asymptomatic infection will not alter their movement abilities. Our approach of combining experimental exposure data and telemetry information provides an analytical framework for quantifying the risk of spread of avian-borne diseases.

Gaidet, Nicolas; Cappelle, Julien; Takekawa, John Y.; Prosser, Diann J.; Iverson, Samuel A.; Douglas, David C.; Perry, William M.; Mundkur, Taej; Newman, Scott H.

2010-01-01

355

[Respiratory failure].  

PubMed

The aged patients are susceptible to respiratory failure, especially acute lung injury (ALI) or acute respiratory distress syndrome (ARDS). The mortality rate for ARDS ranges from 40-70% despite of intensive care using currently available drugs. However, its mechanism still remains to be elucidated. Platelet-activating factor (PAF) and metabolites of arachidonic acid, i.e., eicosanoids, are lipid mediators that have various biological effects including cell adhesion, endothelial cell activation and the production of cytokines. Recent studies using genetically-engineered mice have shown that PAF and cytosolic PLA2 (cPLA2) play an important role in the pathogenesis of ALI. The inhibition of these pathways, PAF and cPLA2, might provide a novel therapeutic approach to ALI. PMID:23855209

Nagase, Takahide

2013-06-01

356

Respiratory allergy  

Microsoft Academic Search

Allergic rhinitis (AR) and asthma are common respiratory allergic disorders which are increasing globally more in developed\\u000a countries. Although much has been written about childhood asthma and guidelines published by various international and national\\u000a fora, not much information is available on AR. This is most common in children, is a significant risk factor for developing\\u000a asthma, is a common comorbidity

Lata Kumar; Meenu Singh

2002-01-01

357

IgA and Respiratory Immunity  

Microsoft Academic Search

\\u000a Large numbers of microbes and microparticles enter the airways with every breath and the respiratory tract thus represents\\u000a a major portal of entry for various viral and bacterial pathogens. In addition to mechanical defenses such as coughing, sneezing,\\u000a and the action of ciliated epithelia, mucosal-associated lymphoid tissue (MALT) plays a critical role in protection of the\\u000a upper and lower respiratory

Dennis W. Metzger

358

Role of surface layer collagen binding protein from indigenous Lactobacillus plantarum 91 in adhesion and its anti-adhesion potential against gut pathogen.  

PubMed

Human feacal isolates were ascertain as genus Lactobacillus using specific primer LbLMA1/R16-1 and further identified as Lactobacillus plantarum with species specific primers Lpl-3/Lpl-2. 25 L. plantarum strains were further assessed for hydrophobicity following the microbial adhesion to hydrocarbons (MATH) method and colonization potentials based on their adherence to immobilized human collagen type-1. Surface proteins were isolated from selected L. plantarum 91(Lp91) strain. The purified collagen binding protein (Cbp) protein was assessed for its anti-adhesion activity against enteric Escherichia coli 0157:H7 pathogen on immobilized collagen. Four L. plantarum strains displayed high degree of hydrophobicity and significant adhesion to collagen. A 72kDa protein was purified which reduced 59.71% adhesion of E. coli 0157:H7 on immobilized collagen as compared to control well during adhesion assay. Cbp protein is the major influencing factor in inhibition of E. coli 0157:H7 adhesion with extracellular matrix (ECM) components. Hydrophobicity and adhesion potential are closely linked attributes precipitating in better colonization potential of the lactobacillus strains. Cbp is substantiated as a crucial surface protein contributing in adhesion of lactobacillus strains. The study can very well be the platform for commercialization of indigenous probiotic strain once their functional attributes are clinically explored. PMID:23890721

Yadav, Ashok Kumar; Tyagi, Ashish; Kaushik, Jai Kumar; Saklani, Asha Chandola; Grover, Sunita; Batish, Virender Kumar

2013-07-26

359

Post-genomic analyses of fungal lignocellulosic biomass degradation reveal the unexpected potential of the plant pathogen Ustilago maydis  

PubMed Central

Background Filamentous fungi are potent biomass degraders due to their ability to thrive in ligno(hemi)cellulose-rich environments. During the last decade, fungal genome sequencing initiatives have yielded abundant information on the genes that are putatively involved in lignocellulose degradation. At present, additional experimental studies are essential to provide insights into the fungal secreted enzymatic pools involved in lignocellulose degradation. Results In this study, we performed a wide analysis of 20 filamentous fungi for which genomic data are available to investigate their biomass-hydrolysis potential. A comparison of fungal genomes and secretomes using enzyme activity profiling revealed discrepancies in carbohydrate active enzymes (CAZymes) sets dedicated to plant cell wall. Investigation of the contribution made by each secretome to the saccharification of wheat straw demonstrated that most of them individually supplemented the industrial Trichoderma reesei CL847 enzymatic cocktail. Unexpectedly, the most striking effect was obtained with the phytopathogen Ustilago maydis that improved the release of total sugars by 57% and of glucose by 22%. Proteomic analyses of the best-performing secretomes indicated a specific enzymatic mechanism of U. maydis that is likely to involve oxido-reductases and hemicellulases. Conclusion This study provides insight into the lignocellulose-degradation mechanisms by filamentous fungi and allows for the identification of a number of enzymes that are potentially useful to further improve the industrial lignocellulose bioconversion process.

2012-01-01

360

Food scarcity, neuroadaptations, and the pathogenic potential of dieting in an unnatural ecology: binge eating and drug abuse.  

PubMed

In the laboratory, food restriction has been shown to induce neuroadaptations in brain reward circuitry which are likely to be among those that facilitate survival during periods of food scarcity in the wild. However, the upregulation of mechanisms that promote foraging and reward-related learning may pose a hazard when food restriction is self-imposed in an ecology of abundant appetitive rewards. For example, episodes of loss of control during weight-loss dieting, use of drugs with addictive potential as diet aids, and alternating fasting with alcohol consumption in order to avoid weight gain, may induce synaptic plasticity that increases the risk of enduring maladaptive reward-directed behavior. In the present mini-review, representative basic research findings are outlined which indicate that food restriction alters the function of mesoaccumbens dopamine neurons, potentiates cellular and behavioral responses to D-1 and D-2 dopamine receptor stimulation, and increases stimulus-induced synaptic insertion of AMPA receptors in nucleus accumbens. Possible mechanistic underpinnings of increased drug reward magnitude, drug-seeking, and binge intake of sucrose in food-restricted animal subjects are discussed and possible implications for human weight-loss dieting are considered. PMID:21530562

Carr, Kenneth D

2011-04-28

361

Food Scarcity, Neuroadaptations, and the Pathogenic Potential of Dieting in an Unnatural Ecology: Binge Eating and Drug Abuse  

PubMed Central

In the laboratory, food restriction has been shown to induce neuroadaptations in brain reward circuitry which are likely to be among those that facilitate survival during periods of food scarcity in the wild. However, the upregulation of mechanisms that promote foraging and reward-related learning may pose a hazard when food restriction is self-imposed in an ecology of abundant appetitive rewards. For example, episodes of loss of control during weight-loss dieting, use of drugs with addictive potential as diet aids, and alternating fasting with alcohol consumption in order to avoid weight gain, may induce synaptic plasticity that increases the risk of enduring maladaptive reward-directed behavior. In the present mini-review, representative basic research findings are outlined which indicate that food restriction alters the function of mesoaccumbens dopamine neurons, potentiates cellular and behavioral responses to D-1 and D-2 dopamine receptor stimulation, and increases stimulus-induced synaptic insertion of AMPA receptors in nucleus accumbens. Possible mechanistic underpinnings of increased drug reward magnitude, drug-seeking, and binge intake of sucrose in food-restricted animal subjects are discussed and possible implications for human weight-loss dieting are considered.

Carr, Kenneth D.

2011-01-01

362

Respiratory tract pathogens isolated from patients hospitalized with suspected pneumonia in Latin America: frequency of occurrence and antimicrobial susceptibility profile: results from the SENTRY Antimicrobial Surveillance Program (1997-2000)  

Microsoft Academic Search

In spite of the recent medical advances, lower respiratory tract infections are still the most frequent infectious causes of mortality worldwide. The objective of this study was to determine the frequency of occurrence and antimicrobial susceptibility of bacterial isolates collected from hospitalized patients with pneumonia in Latin American medical centers during the first four years of the SENTRY Program. The

Ana C Gales; H. élio S Sader; Ronald N Jones

2002-01-01

363

The Impact of Respiratory Viral Infection on Wheezing Illnesses and Asthma Exacerbations  

PubMed Central

The etiology and morbidity associated with asthma are thought to stem from both genetic factors and potentially modifiable environmental factors, such as viral infections.[1-7] Although it is unclear whether respiratory viral infections cause asthma, observational studies have demonstrated a high rate of asthma in children with a history of severe viral lower respiratory tract infections during infancy, and viruses are the associated with the majority of asthma exacerbations among both children and adults. This review will discuss the pathogens associated with virus-induced wheezing illnesses during infancy and early childhood, the association of bronchiolitis during infancy with an increased risk of childhood asthma, and the association of respiratory viruses with asthma exacerbations in older children and adults.

Carroll, Kecia N.; Hartert, Tina V.

2008-01-01

364

Respiratory muscle injury in animal models and humans  

Microsoft Academic Search

Respiratory muscle injury may result from excessive loading due to a decrease in respiratory muscle strength, an increase in the work of breathing, or an increase in the rate of ventilation. Other conditions such as hypoxemia, hypercapnia, aging, decreased nutrition, and immobilization may potentiate respiratory muscle injury. Respiratory muscle injury has been shown in animal models using direct muscle or

W. Darlene Reid; Nori A. MacGowan

1998-01-01

365

Nickel subsulfide is genotoxic in vitro but shows no mutagenic potential in respiratory tract tissues of BigBlue rats and Muta Mouse mice in vivo after inhalation.  

PubMed

Carcinogenic nickel compounds are known to induce promutagenic DNA lesions such as DNA strand breaks and DNA adducts in cultured mammalian cells. In standard mutation assays, in contrast, they were found to be either inactive or weakly active. In our in vitro mutation studies in a lacI transgenic embryonic fibroblast cell line, nickel subsulfide (Ni3S2) increased mutation frequency up to 4. 5-fold. We subsequently applied the comet assay and transgenic rodent mutation assays to investigate the DNA damaging effect and mutagenic potential of nickel subsulfide in target cells of carcinogenesis. A 2-h in vitro treatment of freshly isolated mouse nasal mucosa and lung cells with nickel subsulfide clearly induced DNA fragmentation in a concentration dependent manner. The strong effect was not seen in the same cell types following inhalative treatment of mice and rats, leading only in the mouse nasal mucosa to high DNA damage. When the same inhalative treatment was applied to lacZ and lacI transgenic mice and rats, the spontaneous mutation frequency of these target genes in the respiratory tissues was not increased. These results support a recently proposed non-genotoxic model of nickel carcinogenesis, which acts through gene silencing via DNA methylation and chromatin condensation. This model may also explain our in vitro mutation data in the lacI transgenic cell line, in which nickel subsulfide increased mutation frequency, but in about one-third of the mutants, molecular analysis did not reveal any DNA sequence change in the coding region of the lacI gene despite of the phenotypic loss of its function. PMID:9838057

Mayer, C; Klein, R G; Wesch, H; Schmezer, P

1998-12-01

366

Advances in Diagnosis of Respiratory Virus Infections  

PubMed Central

The diagnosis of respiratory virus infections has evolved substantially in recent years, with the emergence of new pathogens and the development of novel detection methods. While recent advances have improved the sensitivity and turn-around time of diagnostic tests for respiratory viruses, they have also raised important issues such as cost, and the clinical significance of detecting multiple viruses in a single specimen by molecular methods. This article reviews recent advances in specimen collection and detection methods for diagnosis of respiratory virus infections, and discusses the performance characteristics and limitations of these methods.

Loeffelholz, Michael; Chonmaitree, Tasnee

2010-01-01

367

Pathogenic rare copy number variants in community-based schizophrenia suggest a potential role for clinical microarrays.  

PubMed

Individually rare, large copy number variants (CNVs) contribute to genetic vulnerability for schizophrenia. Unresolved questions remain, however, regarding the anticipated yield of clinical microarray testing in schizophrenia. Using high-resolution genome-wide microarrays and rigorous methods, we investigated rare CNVs in a prospectively recruited community-based cohort of 459 unrelated adults with schizophrenia and estimated the minimum prevalence of clinically significant CNVs that would be detectable on a clinical microarray. A blinded review by two independent clinical cytogenetic laboratory directors of all large (>500 kb) rare CNVs in cases and well-matched controls showed that those deemed to be clinically significant were highly enriched in schizophrenia (16.4-fold increase, P < 0.0001). In a single community catchment area, the prevalence of individuals with these CNVs was 8.1%. Rare 1.7 Mb CNVs at 2q13 were found to be significantly associated with schizophrenia for the first time, compared with the prevalence in 23 838 population-based controls (42.9-fold increase, P = 0.0002). Additional novel findings that will facilitate the future clinical interpretation of smaller CNVs in schizophrenia include: (i) a greater proportion of individuals with two or more rare exonic CNVs >10 kb in size (1.5-fold increase, P = 0.0109) in schizophrenia; (ii) the systematic discovery of new candidate genes for schizophrenia; and, (iii) functional gene enrichment mapping highlighting a differential impact in schizophrenia of rare exonic deletions involving diverse functions, including neurodevelopmental and synaptic processes (4.7-fold increase, P = 0.0060). These findings suggest consideration of a potential role for clinical microarray testing in schizophrenia, as is now the suggested standard of care for related developmental disorders like autism. PMID:23813976

Costain, Gregory; Lionel, Anath C; Merico, Daniele; Forsythe, Pamela; Russell, Kathryn; Lowther, Chelsea; Yuen, Tracy; Husted, Janice; Stavropoulos, Dimitri J; Speevak, Marsha; Chow, Eva W C; Marshall, Christian R; Scherer, Stephen W; Bassett, Anne S

2013-06-27

368

EXPERIMENTAL INFECTION OF THE RESPIRATORY TRACT WITH MYCOPLASMA PNEUMONIAE  

EPA Science Inventory

Mycoplasma pneumoniae, a common human respiratory pathogen, has been studied experimentally for years using intranasal inoculation of the golden Sytrian hamster. Because of recent evidence outlining the role in pulmonary immune development of particle size and depth of mycoplasma...

369

Propagation of respiratory aerosols by the vuvuzela.  

PubMed

Vuvuzelas, the plastic blowing horns used by sports fans, recently achieved international recognition during the FIFA World Cup soccer tournament in South Africa. We hypothesised that vuvuzelas might facilitate the generation and dissemination of respiratory aerosols. To investigate the quantity and size of aerosols emitted when the instrument is played, eight healthy volunteers were asked to blow a vuvuzela. For each individual the concentration of particles in expelled air was measured using a six channel laser particle counter and the duration of blowing and velocity of air leaving the vuvuzela were recorded. To allow comparison with other activities undertaken at sports events each individual was also asked to shout and the measurements were repeated while using a paper cone to confine the exhaled air. Triplicate measurements were taken for each individual. The mean peak particle counts were 658 × 10(3) per litre for the vuvuzela and 3.7 × 10(3) per litre for shouting, representing a mean log(10) difference of 2.20 (95% CI: 2.03,2.36; p < 0.001). The majority (>97%) of particles captured from either the vuvuzela or shouting were between 0.5 and 5 microns in diameter. Mean peak airflows recorded for the vuvuzela and shouting were 6.1 and 1.8 litres per second respectively. We conclude that plastic blowing horns (vuvuzelas) have the capacity to propel extremely large numbers of aerosols into the atmosphere of a size able to penetrate the lower lung. Some respiratory pathogens are spread via contaminated aerosols emitted by infected persons. Further investigation is required to assess the potential of the vuvuzela to contribute to the transmission of aerosol borne diseases. We recommend, as a precautionary measure, that people with respiratory infections should be advised not to blow their vuvuzela in enclosed spaces and where there is a risk of infecting others. PMID:21629778

Lai, Ka-Man; Bottomley, Christian; McNerney, Ruth

2011-05-23

370

Propagation of Respiratory Aerosols by the Vuvuzela  

PubMed Central

Vuvuzelas, the plastic blowing horns used by sports fans, recently achieved international recognition during the FIFA World Cup soccer tournament in South Africa. We hypothesised that vuvuzelas might facilitate the generation and dissemination of respiratory aerosols. To investigate the quantity and size of aerosols emitted when the instrument is played, eight healthy volunteers were asked to blow a vuvuzela. For each individual the concentration of particles in expelled air was measured using a six channel laser particle counter and the duration of blowing and velocity of air leaving the vuvuzela were recorded. To allow comparison with other activities undertaken at sports events each individual was also asked to shout and the measurements were repeated while using a paper cone to confine the exhaled air. Triplicate measurements were taken for each individual. The mean peak particle counts were 658×103 per litre for the vuvuzela and 3.7×103 per litre for shouting, representing a mean log10 difference of 2.20 (95% CI: 2.03,2.36; p<0.001). The majority (>97%) of particles captured from either the vuvuzela or shouting were between 0.5 and 5 microns in diameter. Mean peak airflows recorded for the vuvuzela and shouting were 6.1 and 1.8 litres per second respectively. We conclude that plastic blowing horns (vuvuzelas) have the capacity to propel extremely large numbers of aerosols into the atmosphere of a size able to penetrate the lower lung. Some respiratory pathogens are spread via contaminated aerosols emitted by infected persons. Further investigation is required to assess the potential of the vuvuzela to contribute to the transmission of aerosol borne diseases. We recommend, as a precautionary measure, that people with respiratory infections should be advised not to blow their vuvuzela in enclosed spaces and where there is a risk of infecting others.

Lai, Ka-Man; Bottomley, Christian; McNerney, Ruth

2011-01-01

371

Characterization of severe acute respiratory syndrome-associated coronavirus (SARS-CoV) spike glycoprotein-mediated viral entry  

Microsoft Academic Search

Severe acute respiratory syndrome-associated coronavirus (SARS-CoV) is a rapidly emerging pathogen with potentially serious consequences for public health. Here we describe conditions that result not only in the efficient expression of the SARS-CoV spike (S) protein on the surface of cells, but in its incorporation into lentiviral particles that can be used to transduce cells in an S glycoprotein-dependent manner.

Graham Simmons; Jacqueline D. Reeves; Andrew J. Rennekamp; Sean M. Amberg; Andrew J. Piefer; Paul Bates

2004-01-01

372

Mechanistic links between acute respiratory tract infections and acute coronary syndromes.  

PubMed

Cardiovascular disease has emerged as the leading cause of mortality worldwide. Acute coronary syndromes occur as a result of thrombotic complications at the site of atherosclerotic plaques, often following rupture of the fibrous cap of vulnerable plaques. A growing body of evidence from clinical and experimental studies suggests that acute respiratory tract infections can act as a trigger for acute coronary syndromes. The mechanism underlying this association has yet to be established. We explore the mechanistic links between acute respiratory tract infection and acute coronary syndromes, with a particular focus on the host response to infection and its potential interaction with pathogenic processes involved in atherosclerosis and atherosclerotic plaque rupture. The prothrombotic and haemodynamic effects of acute respiratory infection are also discussed. We review mechanistic studies as well as clinical trial data to investigate potential links between acute coronary syndromes and acute respiratory infection. Understanding the link between acute respiratory infections and acute coronary syndromes should help improve the outcome of acute coronary syndromes. PMID:23046969

Bazaz, Rohit; Marriott, Helen M; Francis, Sheila E; Dockrell, David H

2012-10-06

373

Characterization of the mitochondrial respiratory pathways in Candida albicans  

Microsoft Academic Search

Candida albicans is an opportunistic oral pathogen. The flexibility of this microorganism in response to environmental changes includes the expression of a cyanide-resistant alternative respiratory pathway. In the present study, we characterized both conventional and alternative respiratory pathways and determined their ADP\\/O ratios, inhibitor sensitivity profiles and the impact of the utilization of either pathway on susceptibility to commonly used

Eva J Helmerhorst; Michael P Murphy; Robert F Troxler; Frank G Oppenheim

2002-01-01

374

[Respiratory allergies].  

PubMed

Respiratory allergies represent a global and public health problem, due to their prevalence (still increasing), morbidity, impact on the quality of life and costs for the society. They mainly concern rhinitis (or rhinoconjunctivitis) and asthma. The diagnosis of allergy is dependent on a history of symptoms on exposure to an allergen together with the detection of allergen-specific IgE. Accurate diagnosis of allergies opens up therapeutic options that are otherwise not appropriate, such as allergen immunotherapy and allergen avoidance, that are prescribed following a stepwise approach. It has been a century since the first trial in specific immunotherapy was performed and this still remains the only disease modifying treatment for allergic individuals. In terms of route of administration, sublingual immunotherapy represents a good alternative to subcutaneous immunotherapy, considering its proven efficacy and better safety profile. PMID:22884514

Chiriac, Anca Mirela; Demoly, Pascal

2012-08-09

375

Protein Chip Array Profiling Analysis in Patients with Severe Acute Respiratory Syndrome Identified Serum Amyloid A Protein as a Biomarker Potentially Useful in Monitoring the Extent of Pneumonia  

Microsoft Academic Search

Background: A new strain of coronavirus (CoV) has caused an outbreak of severe acute respiratory syn- drome (SARS), with 8098 individuals being infected and 774 deaths worldwide. We carried out protein chip array profiling analysis in an attempt to identify biomarkers that might be useful in monitoring the clinical course of SARS patients. Methods: We performed surface-enhanced laser desorp- tion

Timothy T. C. Yip; Johnny W. M. Chan; William C. S. Cho; Tai-Tung Yip; Zheng Wang; Ting-Lok Kwan; Stephen C. K. Law; Dominic N. C. Tsang; John K. C. Chan; King-Chung Lee; Wai-Wai Cheng; Victor W. S. Ma; Christine Yip; Cadmon K. P. Lim; Roger K. C. Ngan; Joseph S. K. Au; Angel Chan; Wilina W. L. Lim

376

Characterization of antibiotic-resistant and potentially pathogenic Escherichia coli from soil fertilized with litter of broiler chickens fed antimicrobial-supplemented diets.  

PubMed

The objective of this study was to characterize antimicrobial resistance and virulence determinants of Escherichia coli from soil amended with litter from 36-day-old broiler chickens ( Gallus gallus domesticus ) fed with diets supplemented with a variety of antimicrobial agents. Soil samples were collected from plots before and periodically after litter application in August to measure E. coli numbers. A total of 295 E. coli were isolated from fertilized soil samples between August and March. Antibiotic susceptibility was determined by Sensititre, and polymerase chain reaction was performed to detect the presence of resistance and virulence genes. The results confirmed that E. coli survived and could be quantified by direct plate count for at least 7 months in soil following litter application in August. The effects of feed supplementation were observed on E. coli numbers in November and January. Among the 295 E. coli, the highest antibiotic resistance level was observed against tetracycline and ?-lactams associated mainly with the resistance genes tetB and bla(CMY-2), respectively. Significant treatment effects were observed for phylogenetic groups, antibiotic resistance profiles, and virulence gene frequencies. Serotyping, phylogenetic grouping, and pulsed-field gel electrophoresis confirmed that multiple-antibiotic-resistant and potentially pathogenic E. coli can survive in soil fertilized with litter for several months regardless of antimicrobials used in the feed. PMID:22906311

Merchant, Laura E; Rempel, Heidi; Forge, Tom; Kannangara, Tissa; Bittman, Shabtai; Delaquis, Pascal; Topp, Edward; Ziebell, Kim A; Diarra, Moussa S

2012-08-20

377

Recovery and screening for antibiotic susceptibility of potential bacterial pathogens from the oral cavity of shark species involved in attacks on humans in Recife, Brazil.  

PubMed

The number of incidents involving sharks and humans at beaches in Recife, on the north-eastern Brazilian coast, is among the highest worldwide. In addition, wound infections in survivors are common; but the nature and risk of the aetiological agents is unknown. In the present study, 81 potential bacterial pathogens were identified in the oral cavity of sharks involved in attacks in Recife, and were subjected to antibiotic susceptibility tests using the standardized disc-diffusion method. The majority were enterobacteria such as Enterobacter spp., Citrobacter spp., Proteus spp., Providencia alcalifaciens, Escherichia coli, Moellerella wisconcensis and Leclercia adecarboxylata. Other Gram-negative bacteria included Vibrio spp., Burkholderia cepacia, Acinetobacter spp. and Pseudomonas spp. In addition, coagulase-positive and coagulase-negative Staphylococcus spp., Enterococcus spp. and Micrococcus spp. were identified, besides Streptococcus spp. from the viridans group. Resistance was especially found in the Proteus mirabilis and Citrobacter freundii, and ranged from 4 to 6 antibiotics out of the 13 tested. Gentamicin and vancomycin were the most effective against Gram-positive cocci strains, whereas levofloxacin was fully inhibitory against Gram-positive and Gram-negative bacteria. These data are discussed in light of a retrospective evaluation of the medical records of three shark victims treated at Restauração Hospital in Recife. PMID:20413619

Interaminense, J A; Nascimento, D C O; Ventura, R F; Batista, J E C; Souza, M M C; Hazin, F H V; Pontes-Filho, N T; Lima-Filho, J V

2010-04-22

378

Roles of oxidation-reduction potential in electrolyzed oxidizing and chemically modified water for the inactivation of food-related pathogens.  

PubMed

This study investigates the properties of electrolyzed oxidizing (EO) water for the inactivation of pathogen and to evaluate the chemically modified solutions possessing properties similar to EO water in killing Escherichia coli O157:H7. A five-strain cocktail (10(10) CFU/ml) of E. coli O157:H7 was subjected to deionized water (control), EO water with 10 mg/liter residual chlorine (J.A.W-EO water), EO water with 56 mg/liter residual chlorine (ROX-EO water), and chemically modified solutions. Inactivation (8.88 log10 CFU/ml reduction) of E. coli O157:H7 occurred within 30 s after application of EO water and chemically modified solutions containing chlorine and 1% bromine. Iron was added to EO or chemically modified solutions to reduce oxidation-reduction potential (ORP) readings and neutralizing buffer was added to neutralize chlorine. J.A.W-EO water with 100 mg/liter iron, acetic acid solution, and chemically modified solutions containing neutralizing buffer or 100 mg/liter iron were ineffective in reducing the bacteria population. ROX-EO water with 100 mg/liter iron was the only solution still effective in inactivation of E. coli O157:H7 and having high ORP readings regardless of residual chlorine. These results suggest that it is possible to simulate EO water by chemically modifying deionized water and ORP of the solution may be the primary factor affecting microbial inactivation. PMID:10643764

Kim, C; Hung, Y C; Brackett, R E

2000-01-01

379

Methicillin-resistant staphylococci (MRS) and extended-spectrum beta-lactamases (ESBL)-producing Enterobacteriaceae in companion animals: Nosocomial infections as one reason for the rising prevalence of these potential zoonotic pathogens in clinical samples  

Microsoft Academic Search

The ongoing change in the relationship between humans and companion animals is hallmarked by the increasing intensive care provided to companion animals in veterinary medicine, resulting in growing numbers of high-risk animal patients. The emergence of nosocomial infections in small animal clinics is one of the major drawbacks of this development, especially in terms of multidrug-resistance and potentially zoonotic pathogens.

Lothar H. Wieler; Christa Ewers; Sebastian Guenther; Birgit Walther; Antina Lübke-Becker

2011-01-01

380

FOODBORNE PATHOGENS IN DAIRY ENVIRONMENTS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Outbreaks of foodborne illnesses caused by pathogenic bacteria are increasingly being linked to fresh produce. Animal manure is a potential pathogen reservoir, and the close proximity of dairy operations and croplands in California cannot be ignored. We have worked on developing improved detection m...

381

A Legacy of Low-Impact Logging does not Elevate Prevalence of Potentially Pathogenic Protozoa in Free-Ranging Gorillas and Chimpanzees in the Republic of Congo: Logging and Parasitism in African Apes  

PubMed Central

Many studies have examined the long-term effects of selective logging on the abundance and diversity of free-ranging primates. Logging is known to reduce the abundance of some primate species through associated hunting and the loss of food trees for frugivores; however, the potential role of pathogens in such primate population declines is largely unexplored. Selective logging results in a suite of alterations in host ecology and forest structure that may alter pathogen dynamics in resident wildlife populations. In addition, environmental pollution with human fecal material may present a risk for wildlife infections with zoonotic protozoa, such as Cryptosporidium and Giardia. To better understand this interplay, we compared patterns of infection with these potentially pathogenic protozoa in sympatric western lowland gorillas (Gorilla gorilla gorilla) and chimpanzees (Pan troglodytes troglodytes) in the undisturbed Goualougo Triangle of Nouabalé-Ndoki National Park and the adjacent previously logged Kabo Concession in northern Republic of Congo. No Cryptosporidium infections were detected in any of the apes examined and prevalence of infection with Giardia was low (3.73% overall) and did not differ between logged and undisturbed forest for chimpanzees or gorillas. These results provide a baseline for prevalence of these protozoa in forest-dwelling African apes and suggest that low-intensity logging may not result in long-term elevated prevalence of potentially pathogenic protozoa.

Morgan, David; Deutsch, J. Charlie; Kuhlenschmidt, Mark S.; Salzer, Johanna S.; Cameron, Kenneth; Reed, Trish; Sanz, Crickette

2010-01-01

382

A legacy of low-impact logging does not elevate prevalence of potentially pathogenic protozoa in free-ranging gorillas and chimpanzees in the Republic of Congo: logging and parasitism in African apes.  

PubMed

Many studies have examined the long-term effects of selective logging on the abundance and diversity of free-ranging primates. Logging is known to reduce the abundance of some primate species through associated hunting and the loss of food trees for frugivores; however, the potential role of pathogens in such primate population declines is largely unexplored. Selective logging results in a suite of alterations in host ecology and forest structure that may alter pathogen dynamics in resident wildlife populations. In addition, environmental pollution with human fecal material may present a risk for wildlife infections with zoonotic protozoa, such as Cryptosporidium and Giardia. To better understand this interplay, we compared patterns of infection with these potentially pathogenic protozoa in sympatric western lowland gorillas (Gorilla gorilla gorilla) and chimpanzees (Pan troglodytes troglodytes) in the undisturbed Goualougo Triangle of Nouabalé-Ndoki National Park and the adjacent previously logged Kabo Concession in northern Republic of Congo. No Cryptosporidium infections were detected in any of the apes examined and prevalence of infection with Giardia was low (3.73% overall) and did not differ between logged and undisturbed forest for chimpanzees or gorillas. These results provide a baseline for prevalence of these protozoa in forest-dwelling African apes and suggest that low-intensity logging may not result in long-term elevated prevalence of potentially pathogenic protozoa. PMID:20238141

Gillespie, Thomas R; Morgan, David; Deutsch, J Charlie; Kuhlenschmidt, Mark S; Salzer, Johanna S; Cameron, Kenneth; Reed, Trish; Sanz, Crickette

2010-03-18

383

[New strategy for treatment of respiratory infection and the predominance of traditional Chinese medicine].  

PubMed

Respiratory infection is a common illness. Antibiotic therapy is an essential treatment in clinical practices, but it is challenged by drug-resistant pathogenic microbes. Nowadays, there are many great improvements in some novel non-antimicrobial therapies for preventing and treating respiratory infection, such as enhancing the secretion of endogenous antibiotic peptides to improve innate immune defense of mucous membrane, attaching importance to research and application of vaccine over again, reducing the adhesion and attachment of microbes to block their invasion, and treating systemic inflammatory response syndrome resulting from severe infection. In Chinese herbal pharmacological studies, we found some herbs have antimicrobial function, and furthermore, these herbs have potential effects of immunoregulation. Chinese herbs are worthy of tapping potentialities of research and exploiture. PMID:15339434

Wang, Yi-Yu

2004-05-01

384

Quantification of the respiratory burst response as an indicator of innate immune health in zebrafish.  

PubMed

The phagocyte respiratory burst is part of the innate immune response to pathogen infection and involves the production of reactive oxygen species (ROS). ROS are toxic and function to kill phagocytized microorganisms. In vivo quantification of phagocyte-derived ROS provides information regarding an organism's ability to mount a robust innate immune response. Here we describe a protocol to quantify and compare ROS in whole zebrafish embryos upon chemical induction of the phagocyte respiratory burst. This method makes use of a non-fluorescent compound that becomes fluorescent upon oxidation by ROS. Individual zebrafish embryos are pipetted into the wells of a microplate and incubated in this fluorogenic substrate with or without a chemical inducer of the respiratory burst. Fluorescence in each well is quantified at desired time points using a microplate reader. Fluorescence readings are adjusted to eliminate background fluorescence and then compared using an unpaired t-test. This method allows for comparison of the respiratory burst potential of zebrafish embryos at different developmental stages and in response to experimental manipulations such as protein knockdown, overexpression, or treatment with pharmacological agents. This method can also be used to monitor the respiratory burst response in whole dissected kidneys or cell preparations from kidneys of adult zebrafish and some other fish species. We believe that the relative simplicity and adaptability of this protocol will complement existing protocols and will be of interest to researchers who seek to better understand the innate immune response. PMID:24056405

Goody, Michelle F; Peterman, Eric; Sullivan, Con; Kim, Carol H

2013-09-12

385

Topical curcumin can inhibit deleterious effects of upper respiratory tract bacteria on human oropharyngeal cells in vitro: potential role for patients with cancer therapy induced mucositis?  

Microsoft Academic Search

Purpose  Curcumin exerts its anti-inflammatory activity via inhibition of nuclear factor ?B. Oropharyngeal epithelia and residing bacteria\\u000a closely interact in inflammation and infection. This in vitro model investigated the effects of curcumin on bacterial survival,\\u000a adherence to, and invasion of upper respiratory tract epithelia, and studied its anti-inflammatory effect. We aimed to establish\\u000a a model, which could offer insights into the

Sonja Lüer; Rolf Troller; Marion Jetter; Violeta Spaniol; Christoph Aebi

2011-01-01

386

Signal transduction pathways involved in low intensity He-Ne laser-induced respiratory burst in bovine neutrophils: A potential mechanism of low intensity laser biostimulation  

Microsoft Academic Search

Background and Objective: Low intensity He-Ne laser irradiation has been reported to induce respiratory burst of neutrophils for a long time, but the mechanism remains obscure. We speculated that it is mediated by some signal transduction pathways. Study Design\\/Materials and Methods: The protein tyrosine kinases (PTKs) inhibitor, genistein, the phospho- lipase C (PLC) inhibitor, U-73122, and the protein kinase C

Rui Duan; Timon Cheng-Yi Liu; Yan Li; Hong Guo; Li-Bo Yao

2001-01-01

387

Activation of the Human Mitochondrial Transcription Factor A Gene by Nuclear Respiratory Factors: A Potential Regulatory Link Between Nuclear and Mitochondrial Gene Expression in Organelle Biogenesis  

Microsoft Academic Search

Mitochondrial transcription factor A (mtTFA), the product of a nuclear gene, stimulates transcription from the two divergent mitochondrial promoters and is likely the principal activator of mitochondrial gene expression in vertebrates. Here we establish that the proximal promoter of the human mtTFA gene is highly dependent upon recognition sites for the nuclear respiratory factors, NRF-1 and NRF-2, for activity. These

Joseph V. Virbasius; Richard C. Scarpulla

1994-01-01

388

Satellite Tracking on the Flyways of Brown-Headed Gulls and Their Potential Role in the Spread of Highly Pathogenic Avian Influenza H5N1 Virus  

PubMed Central

Brown-headed gulls (Larus brunnicephalus), winter visitors of Thailand, were tracked by satellite telemetry during 2008–2011 for investigating their roles in the highly pathogenic avian influenza (HPAI) H5N1 virus spread. Eight gulls negative for influenza virus infection were marked with solar-powered satellite platform transmitters at Bang Poo study site in Samut Prakarn province, Thailand; their movements were monitored by the Argos satellite tracking system, and locations were mapped. Five gulls completed their migratory cycles, which spanned 7 countries (China, Bangladesh, India, Myanmar, Thailand, Cambodia, and Vietnam) affected by the HPAI H5N1 virus. Gulls migrated from their breeding grounds in China to stay overwinter in Thailand and Cambodia; while Bangladesh, India, Myanmar, and Vietnam were the places of stopovers during migration. Gulls traveled an average distance of about 2400 km between Thailand and China and spent 1–2 weeks on migration. Although AI surveillance among gulls was conducted at the study site, no AI virus was isolated and no H5N1 viral genome or specific antibody was detected in the 75 gulls tested, but 6.6% of blood samples were positive for pan-influenza A antibody. No AI outbreaks were reported in areas along flyways of gulls in Thailand during the study period. Distance and duration of migration, tolerability of the captive gulls to survive the HPAI H5N1 virus challenge and days at viral shedding after the virus challenging suggested that the Brown-headed gull could be a potential species for AI spread, especially among Southeast Asian countries, the epicenter of H5N1 AI outbreak.

Ratanakorn, Parntep; Wiratsudakul, Anuwat; Wiriyarat, Witthawat; Eiamampai, Krairat; Farmer, Adrian H.; Webster, Robert G.; Chaichoune, Kridsada; Suwanpakdee, Sarin; Pothieng, Duangrat; Puthavathana, Pilaipan

2012-01-01

389

Satellite tracking on the flyways of brown-headed gulls and their potential role in the spread of highly pathogenic avian influenza H5N1 virus.  

PubMed

Brown-headed gulls (Larus brunnicephalus), winter visitors of Thailand, were tracked by satellite telemetry during 2008-2011 for investigating their roles in the highly pathogenic avian influenza (HPAI) H5N1 virus spread. Eight gulls negative for influenza virus infection were marked with solar-powered satellite platform transmitters at Bang Poo study site in Samut Prakarn province, Thailand; their movements were monitored by the Argos satellite tracking system, and locations were mapped. Five gulls completed their migratory cycles, which spanned 7 countries (China, Bangladesh, India, Myanmar, Thailand, Cambodia, and Vietnam) affected by the HPAI H5N1 virus. Gulls migrated from their breeding grounds in China to stay overwinter in Thailand and Cambodia; while Bangladesh, India, Myanmar, and Vietnam were the places of stopovers during migration. Gulls traveled an average distance of about 2400 km between Thailand and China and spent 1-2 weeks on migration. Although AI surveillance among gulls was conducted at the study site, no AI virus was isolated and no H5N1 viral genome or specific antibody was detected in the 75 gulls tested, but 6.6% of blood samples were positive for pan-influenza A antibody. No AI outbreaks were reported in areas along flyways of gulls in Thailand during the study period. Distance and duration of migration, tolerability of the captive gulls to survive the HPAI H5N1 virus challenge and days at viral shedding after the virus challenging suggested that the Brown-headed gull could be a potential species for AI spread, especially among Southeast Asian countries, the epicenter of H5N1 AI outbreak. PMID:23209623

Ratanakorn, Parntep; Wiratsudakul, Anuwat; Wiriyarat, Witthawat; Eiamampai, Krairat; Farmer, Adrian H; Webster, Robert G; Chaichoune, Kridsada; Suwanpakdee, Sarin; Pothieng, Duangrat; Puthavathana, Pilaipan

2012-11-28

390

Candida albicans pathogenicity mechanisms  

PubMed Central

The polymorphic fungus Candida albicans is a member of the normal human microbiome. In most individuals, C. albicans resides as a lifelong, harmless commensal. Under certain circumstances, however, C. albicans can cause infections that range from superficial infections of the skin to life-threatening systemic infections. Several factors and activities have been identified which contribute to the pathoge