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Sample records for aureus causing invasive

  1. Geographic distribution of Staphylococcus aureus causing invasive infections in Europe: a molecular-epidemiological analysis.

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    Hajo Grundmann

    2010-01-01

    Full Text Available BACKGROUND: Staphylococcus aureus is one of the most important human pathogens and methicillin-resistant variants (MRSAs are a major cause of hospital and community-acquired infection. We aimed to map the geographic distribution of the dominant clones that cause invasive infections in Europe. METHODS AND FINDINGS: In each country, staphylococcal reference laboratories secured the participation of a sufficient number of hospital laboratories to achieve national geo-demographic representation. Participating laboratories collected successive methicillin-susceptible (MSSA and MRSA isolates from patients with invasive S. aureus infection using an agreed protocol. All isolates were sent to the respective national reference laboratories and characterised by quality-controlled sequence typing of the variable region of the staphylococcal spa gene (spa typing, and data were uploaded to a central database. Relevant genetic and phenotypic information was assembled for interactive interrogation by a purpose-built Web-based mapping application. Between September 2006 and February 2007, 357 laboratories serving 450 hospitals in 26 countries collected 2,890 MSSA and MRSA isolates from patients with invasive S. aureus infection. A wide geographical distribution of spa types was found with some prevalent in all European countries. MSSA were more diverse than MRSA. Genetic diversity of MRSA differed considerably between countries with dominant MRSA spa types forming distinctive geographical clusters. We provide evidence that a network approach consisting of decentralised typing and visualisation of aggregated data using an interactive mapping tool can provide important information on the dynamics of MRSA populations such as early signalling of emerging strains, cross border spread, and importation by travel. CONCLUSIONS: In contrast to MSSA, MRSA spa types have a predominantly regional distribution in Europe. This finding is indicative of the selection and spread

  2. Community-Associated Methicillin-Resistant Staphylococcus aureus Lacking PVL, as a Cause of Severe Invasive Infection Treated with Linezolid

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    Catarina Gouveia

    2013-01-01

    Full Text Available Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA is an emerging public health problem worldwide. Severe invasive infections have been described, mostly associated with the presence of Panton-Valentine leukocidin (PVL. In Portugal limited information exists regarding CA-MRSA infections. In this study we describe the case of a previously healthy 12-year-old female, sport athlete, who presented to the hospital with acetabulofemoral septic arthritis, myositis, fasciitis, acetabulum osteomyelitis, and pneumonia. The MRSA isolated from blood and synovial fluid was PVL negative and staphylococcal enterotoxin type P (SEP and type L (SEL positive, with a vancomycin MIC of 1.0 mg/L and resistant to clindamycin and ciprofloxacin. The patient was submitted to multiple surgical drainages and started on vancomycin, rifampicin, and gentamycin. Due to persistence of fever and no microbiological clearance, linezolid was started with improvement. This is one of the few reported cases of severe invasive infection caused by CA-MRSA in Portugal, which was successfully treated with linezolid. In spite of the severity of infection, the MRSA isolate did not produce PVL.

  3. Mechanism and consequences of invasion of endothelial cells by Staphylococcus aureus

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    Sinha, Bhanu; Herrmann, Mathias

    2005-01-01

    It has become clear that Staphylococcus aureus is a facultative intracellular microorganism. Adherence and invasion are a prerequisite for endovascular infections caused by S. aureus, such as infective endocarditis. These phenomena may also be involved in the pathogenesis of invasive and metastatic

  4. Systemic Staphylococcus aureus infection mediated by Candida albicans hyphal invasion of mucosal tissue

    NARCIS (Netherlands)

    L.M. Schlecht; B.M. Peters; B.P. Krom; J.A. Freiberg; G.M. Hänsch; S.G. Filler; M.A. Jabra-Rizk; M.E. Shirtliff

    2015-01-01

    Candida albicans and Staphylococcus aureus are often co-isolated in cases of biofilm-associated infections. C. albicans can cause systemic disease through morphological switch from the rounded yeast to the invasive hyphal form. Alternatively, systemic S. aureus infections arise from seeding through

  5. Antibody responses in patients with invasive Staphylococcus aureus infections

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    Jacobsson, G; Colque-Navarro, P.; Gustafsson, E.; Andersson, R.; Möllby, R

    2010-01-01

    Abstract Correlation between antibody response and clinical outcome in Staphylococcus aureus bacteremia has yielded conflicting results. Immunization schedules have failed in clinical trials. Is the humoral response toward S. aureus of protective nature? A prospective study was performed in patients with invasive S. aureus (ISA) infections during the period 2003?2005. The antibody levels were determined at the beginning and at the end of treatment and one month later (n?=?96, n?=?7...

  6. A Caenorhabditis elegans Host Model Correlates with Invasive Disease Caused by Staphylococcus aureus Recovered during an Outbreak in Neonatal Intensive Care

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    Kaiyu Wu

    2012-01-01

    Full Text Available BACKGROUND: Caenorhabditis elegans has previously been used as a host model to determine the virulence of clinical methicillin-resistant Staphylococcus aureus isolates. In the present study, methicillin-susceptible S aureus (MSSA strains associated with an outbreak in a neonatal intensive care unit (NICU were investigated using the C elegans model.

  7. Mapping the Distribution of Invasive Staphylococcus aureus across Europe

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    Grundmann, Hajo; Aanensen, David M.; van den Wijngaard, Cees C.; Brian G Spratt; Harmsen, Dag; Friedrich, Alexander W.; ,

    2010-01-01

    Editors' Summary Background The bacterium Staphylococcus aureus lives on the skin and in the nose of about a third of healthy people. Although S. aureus usually coexists peacefully with its human carriers, it is also an important disease-causing organism or pathogen. If it enters the body through a cut or during a surgical procedure, S. aureus can cause minor infections such as pimples and boils or more serious, life-threatening infections such as blood poisoning and pneumonia. Minor S. aureu...

  8. Prevalence of clonal complexes and virulence genes among commensal and invasive Staphylococcus aureus isolates in Sweden.

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    Gunlög Rasmussen

    Full Text Available Staphylococcus aureus encodes a remarkable number of virulence factors which may contribute to its pathogenicity and ability to cause invasive disease. The main objective of this study was to evaluate the association between S. aureus invasiveness and bacterial genotype, in terms of the presence of virulence genes and affiliation to clonal complexes. Also, the significance of different virulence genes, mainly adhesins, for the development of infective endocarditis was investigated. DNA microarray technology was used to analyze 134 S. aureus isolates, all methicillin-susceptible, derived from three groups of clinically well-characterized patients: nasal carriers (n=46, bacteremia (n=55, and bacteremia with infective endocarditis (n=33. Invasive isolates were dominant in four of the major clonal complexes: 5, 8, 15, and 25. Of the 170 virulence genes examined, those encoding accessory gene regulator group II (agr II, capsule polysaccharide serotype 5 (cap5, and adhesins such as S. aureus surface protein G (sasG and fibronectin-binding protein B (fnbB were found to be associated with invasive disease. The same was shown for the leukocidin genes lukD/lukE, as well as the genes encoding serine protease A and B (splA/splB, staphylococcal complement inhibitor (scn and the staphylococcal exotoxin-like protein (setC or selX. In addition, there was a trend of higher prevalence of certain genes or gene clusters (sasG, agr II, cap5 among isolates causing infective endocarditis compared to other invasive isolates. In most cases, the presence of virulence genes was linked to clonal complex affiliation. In conclusion, certain S. aureus clonal lineages harboring specific sets of virulence genes seem to be more successful in causing invasive disease.

  9. Ceftaroline Fosamil Use in 2 Pediatric Patients With Invasive Methicillin-Resistant Staphylococcus aureus Infections

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    Williams, Amanda W.; Newman, Patrick M; Ocheltree, Sara; Beaty, Rachel; Hassoun, Ali

    2015-01-01

    Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is one of the most common pathogens causing pediatric infections including skin and soft tissue infections, pyogenic arthritis, osteomyelitis, and septic shock. For decades, patients were treated with antibiotics such as vancomycin and clindamycin, but there is an increasing incidence of resistance to these traditional therapies. We describe 2 cases of patients with CA-MRSA invasive infections with bacteremia who exper...

  10. Heterologously expressed Staphylococcus aureus fibronectin-binding proteins are sufficient for invasion of host cells

    NARCIS (Netherlands)

    Sinha, B; Francois, P; Que, Y A; Hussain, M; Heilmann, C; Moreillon, P; Lew, D; Krause, K H; Peters, G; Herrmann, M

    2000-01-01

    Staphylococcus aureus invasion of mammalian cells, including epithelial, endothelial, and fibroblastic cells, critically depends on fibronectin bridging between S. aureus fibronectin-binding proteins (FnBPs) and the host fibronectin receptor integrin alpha(5)beta(1) (B. Sinha et al., Cell. Microbiol

  11. Staphylococcus aureus causing tropical pyomyositis, Amazon Basin, Peru.

    NARCIS (Netherlands)

    Garcia, C.; Hallin, M.; Deplano, A.; Denis, O.; Sihuincha, M.; Groot, R. de; Gotuzzo, E.; Jacobs, J.

    2013-01-01

    We studied 12 Staphylococcus aureus isolates causing tropical pyomyositis in the Amazon Basin of Peru. All isolates were methicillin-susceptible; 11 carried Panton-Valentine leukocidin-encoding genes, and 5 belonged to multilocus sequence type 25 and possessed an extensive set of enterotoxins. Our f

  12. Staphylococcus aureus sternal osteomyelitis: a rare cause of chest pain

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    Kaur M

    2015-10-01

    Full Text Available Chest pain is a common presenting symptom with a broad differential. Life-threatening cardiac and pulmonary etiologies of chest pain should be evaluated first. However, it is critical to perform a thorough assessment for other sources of chest pain in order to limit morbidity and mortality from less common causes. We present a rare case of a previously healthy 45 year old man who presented with focal, substernal, reproducible chest pain and Staphylococcus aureus bacteremia who was later found to have primary Staphylococcus aureus sternal osteomyelitis.

  13. Invasive Disease Caused by Nontypeable Haemophilus influenzae

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    de Jonge, Marien I.

    2015-01-01

    The incidence of severe Haemophilus influenza infections, such as sepsis and meningitis, has declined substantially since the introduction of the H. influenzae serotype b vaccine. However, the H. influenzae type b vaccine fails to protect against nontypeable H. influenzae strains, which have become increasingly frequent causes of invasive disease, especially among children and the elderly. We summarize recent literature supporting the emergence of invasive nontypeable H. influenzae and describe mechanisms that may explain its increasing prevalence over the past 2 decades. PMID:26407156

  14. Assessment of adhesion, invasion and cytotoxicity potential of oral Staphylococcus aureus strains.

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    Merghni, Abderrahmen; Ben Nejma, Mouna; Helali, Imen; Hentati, Hajer; Bongiovanni, Antonino; Lafont, Frank; Aouni, Mahjoub; Mastouri, Maha

    2015-09-01

    The oral cavity is regarded as a relevant site for Staphylococcus aureus colonization. However, characterization of virulence mechanisms of oral S. aureus remains to be uncovered. In this study, twenty one S. aureus strains isolated from the oral cavity of Tunisian patients were screened for adherence, invasion and cytotoxicity against HeLa cells. In addition, the presence of adhesins (icaA, icaD, can, fnbA and fnbB) and α-hemolysin (hla) genes in each strain was achieved by polymerase chain reaction (PCR). Our finding revealed that oral S. aureus strains were able to adhere and invade epithelial cells, with variable degrees (P toxin was found in 52.4% of the isolates. All these virulence factors give to S. aureus the right qualities to become a redoubtable pathogen associated to oral infections.

  15. Ceftaroline Fosamil Use in 2 Pediatric Patients With Invasive Methicillin-Resistant Staphylococcus aureus Infections.

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    Williams, Amanda W; Newman, Patrick M; Ocheltree, Sara; Beaty, Rachel; Hassoun, Ali

    2015-01-01

    Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is one of the most common pathogens causing pediatric infections including skin and soft tissue infections, pyogenic arthritis, osteomyelitis, and septic shock. For decades, patients were treated with antibiotics such as vancomycin and clindamycin, but there is an increasing incidence of resistance to these traditional therapies. We describe 2 cases of patients with CA-MRSA invasive infections with bacteremia who experienced vancomycin therapy failure but who were successfully treated with ceftaroline fosamil. Case 1 involves an 8-year-old Hispanic male who was diagnosed with CA-MRSA bacteremia, thigh abscess, and osteomyelitis. The patient was admitted to the pediatric intensive care unit in septic shock. Case 2 involves an 8-year-old Caucasian male who was diagnosed with CA-MRSA sepsis, right arm abscess, and osteomyelitis. We were able to successfully treat both patients with CA-MRSA sepsis and invasive infection-who failed vancomycin therapy-with ceftaroline fosamil with no adverse efiects. Despite the positive outcome in both pediatric patients, clinical trials with ceftaroline fosamil are needed to further support its use in pediatric patients. PMID:26766937

  16. Inhibiting platelets aggregation could aggravate the acute infection caused by Staphylococcus aureus.

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    Zhang, Xin; Liu, Yu; Gao, Yaping; Dong, Jie; Mu, Chunhua; Lu, Qiang; Shao, Ningsheng; Yang, Guang

    2011-01-01

    Several fibrinogen binding proteins (Fibs) play important roles in the pathogenesis of Staphylococcus aureus (S. aureus). Most Fibs can promote the aggregation of platelets during infection, but the extracellular fibrinogen-binding protein (Efb) is an exception. It is reported that Efb can specifically bind fibrinogen and inhibit the aggregation of platelet with its N terminal. However, the biological significance of platelet aggregation inhibition in the infection caused by S. aureus is unclear until now. Here, we demonstrated that the persistence and aggregation of platelets were important for killing S. aureus in whole blood. It was found that the N terminal of Efb (EfbN) and platelets inhibitors could increase the survival of S. aureus in whole blood. The study in vivo also showed that EfbN and platelets inhibitors could reduce the killing of S. aureus and increase the lethality rate of S. aureus in the acute infection mouse model.

  17. Juxtarenal Modular Aortic Stent Graft Infection Caused by Staphylococcus aureus

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    Róbert Novotný

    2016-01-01

    Full Text Available Introduction. We are presenting a case report of an infected modular abdominal stent graft. Case Presentation. A 67-year-old male patient three years after Cook’s modular abdominal aortic aneurysm (AAA graft implantation for juxtarenal AAA with an implantation of a stent extension into the right common iliac artery for type Ib endoleak. The patient was admitted into our center in severe condition with suspected retroperitoneal bleeding. Computed tomography angiography (CTAG confirmed retroperitoneal bleeding in the right common iliac artery. An urgent surgical revision was indicated; destructed arterial wall around the stent extension in the right common iliac artery was discovered. Due to the severe state of health of the patient, a resection of the infected stent and affected arterial wall was performed, followed by an iliac-femoral crossover bypass. The patient was transported to the intensive care unit with hepatic and renal failure, with maximal catecholamine support. Combined antibiotic treatment was started. The patient died five hours after the procedure. The cause of death was multiorgan failure caused by sepsis. Hemocultures and perioperative microbiological cultures showed the infection agent to be Staphylococcus aureus methicillin sensitive. Conclusion. Stent graft infection is a rare complication. Treatment is associated with high mortality and morbidity.

  18. Simvastatin inhibits Staphylococcus aureus host cell invasion through modulation of isoprenoid intermediates

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    Horn, Mary P.; Knecht, Sharmon M.; Rushing, Frances L.; Birdsong, Julie; Siddall, C. Parker; Johnson, Charron M.; Abraham, Terri N.; Brown, Amy; Volk, Catherine B.; Gammon, Kelly; Bishop, Derron L.; McKillip, John L.; McDowell, Susan A.

    2008-01-01

    Patients on a statin regimen are at a decreased risk of death due to bacterial sepsis. We have found that protection by simvastatin includes the inhibition of host cell invasion by Staphylococcus aureus, the most common etiologic agent of sepsis. Inhibition was due in part to depletion of isoprenoid intermediates within the cholesterol biosynthesis pathway and led to the cytosolic accumulation of the small-guanosine triphosphatases (GTPases) CDC42, Rac, and RhoB. Actin stress fiber disassembl...

  19. Staphylococcus aureus seroproteomes discriminate ruminant isolates causing mild or severe mastitis

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    Le Maréchal Caroline; Jardin Julien; Jan Gwenaël; Even Sergine; Pulido Coralie; Guibert Jean-Michel; Hernandez David; François Patrice; Schrenzel Jacques; Demon Dieter; Meyer Evelyne; Berkova Nadia; Thiéry Richard; Vautor Eric; Le Loir Yves

    2011-01-01

    Abstract Staphylococcus aureus is a major cause of mastitis in ruminants. In ewe mastitis, symptoms range from subclinical to gangrenous mastitis. S. aureus factors or host-factors contributing to the different outcomes are not completely elucidated. In this study, experimental mastitis was induced on primiparous ewes using two S. aureus strains, isolated from gangrenous (strain O11) or subclinical (strain O46) mastitis. Strains induced drastically distinct clinical symptoms when tested in ew...

  20. Host Physiologic Changes Induced by Influenza A Virus Lead to Staphylococcus aureus Biofilm Dispersion and Transition from Asymptomatic Colonization to Invasive Disease

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    Ryan M. Reddinger

    2016-08-01

    Full Text Available Staphylococcus aureus is a ubiquitous opportunistic human pathogen and a major health concern worldwide, causing a wide variety of diseases from mild skin infections to systemic disease. S. aureus is a major source of severe secondary bacterial pneumonia after influenza A virus infection, which causes widespread morbidity and mortality. While the phenomenon of secondary bacterial pneumonia is well established, the mechanisms behind the transition from asymptomatic colonization to invasive staphylococcal disease following viral infection remains unknown. In this report, we have shown that S. aureus biofilms, grown on an upper respiratory epithelial substratum, disperse in response to host physiologic changes related to viral infection, such as febrile range temperatures, exogenous ATP, norepinephrine, and increased glucose. Mice that were colonized with S. aureus and subsequently exposed to these physiologic stimuli or influenza A virus coinfection developed pronounced pneumonia. This study provides novel insight into the transition from colonization to invasive disease, providing a better understanding of the events involved in the pathogenesis of secondary staphylococcal pneumonia.

  1. Host Physiologic Changes Induced by Influenza A Virus Lead to Staphylococcus aureus Biofilm Dispersion and Transition from Asymptomatic Colonization to Invasive Disease

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    Reddinger, Ryan M.; Luke-Marshall, Nicole R.

    2016-01-01

    ABSTRACT Staphylococcus aureus is a ubiquitous opportunistic human pathogen and a major health concern worldwide, causing a wide variety of diseases from mild skin infections to systemic disease. S. aureus is a major source of severe secondary bacterial pneumonia after influenza A virus infection, which causes widespread morbidity and mortality. While the phenomenon of secondary bacterial pneumonia is well established, the mechanisms behind the transition from asymptomatic colonization to invasive staphylococcal disease following viral infection remains unknown. In this report, we have shown that S. aureus biofilms, grown on an upper respiratory epithelial substratum, disperse in response to host physiologic changes related to viral infection, such as febrile range temperatures, exogenous ATP, norepinephrine, and increased glucose. Mice that were colonized with S. aureus and subsequently exposed to these physiologic stimuli or influenza A virus coinfection developed pronounced pneumonia. This study provides novel insight into the transition from colonization to invasive disease, providing a better understanding of the events involved in the pathogenesis of secondary staphylococcal pneumonia. PMID:27507829

  2. Bdellovibrio bacteriovorus Inhibits Staphylococcus aureus Biofilm Formation and Invasion into Human Epithelial Cells

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    Monnappa, Ajay K.; Dwidar, Mohammed; Seo, Jeong Kon; Hur, Jin-Hoe; Mitchell, Robert J.

    2014-01-01

    Bdellovibrio bacteriovorus HD100 is a predatory bacterium that attacks many Gram-negative human pathogens. A serious drawback of this strain, however, is its ineffectiveness against Gram-positive strains, such as the human pathogen Staphylococcus aureus. Here we demonstrate that the extracellular proteases produced by a host-independent B. bacteriovorus (HIB) effectively degrade/inhibit the formation of S. aureus biofilms and reduce its virulence. A 10% addition of HIB supernatant caused a 75% or greater reduction in S. aureus biofilm formation as well as 75% dispersal of pre-formed biofilms. LC-MS-MS analyses identified various B. bacteriovorus proteases within the supernatant, including the serine proteases Bd2269 and Bd2321. Tests with AEBSF confirmed that serine proteases were active in the supernatant and that they impacted S. aureus biofilm formation. The supernatant also possessed a slight DNAse activity. Furthermore, treatment of planktonic S. aureus with the supernatant diminished its ability to invade MCF-10a epithelial cells by 5-fold but did not affect the MCF-10a viability. In conclusion, this study illustrates the hitherto unknown ability of B. bacteriovorus to disperse Gram-positive pathogenic biofilms and mitigate their virulence.

  3. Severe invasive methicillin-resistant S. aureus (USA300 clone infection in an Italian adolescent

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    Piero Valentini

    2009-12-01

    Full Text Available This report describes an uncommon presentation of invasive community-acquired methicillin-resistant S. aureus (CA-MRSA infection in an immunocompetent adolescent without any other risk factor, characterized by septicaemia, meningitis, necrotising pneumonia and deep venous thrombosis (DVT. Successful treatment was performed with linezolid, rifampicin and low-molecular-weight heparin (LMWH. MRSA molecular typing revealed the presence of Panton-Valentine leukocidin (PVL gene, and a genetic background identical to USA300 clone, an emerging aggressive CA-MRSA strain in USA and Europe.

  4. Impact of sub-inhibitory antibiotics on fibronectin-mediated host cell adhesion and invasion by Staphylococcus aureus

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    Rasigade Jean

    2011-12-01

    Full Text Available Abstract Background Staphylococcus aureus is a well-armed pathogen prevalent in severe infections such as endocarditis and osteomyelitis. Fibronectin-binding proteins A and B, encoded by fnbA/B, are major pathogenesis determinants in these infections through their involvement in S. aureus adhesion to and invasion of host cells. Sub-minimum inhibitory concentrations (sub-MICs of antibiotics, frequently occurring in vivo because of impaired drug diffusion at the infection site, can alter S. aureus phenotype. We therefore investigated their impact on S. aureus fibronectin-mediated adhesiveness and invasiveness. Methods After in vitro challenge of S. aureus 8325-4 and clinical isolates with sub-MICs of major anti-staphylococcal agents, we explored fnbA/B transcription levels, bacterial adhesiveness to immobilised human fibronectin and human osteoblasts in culture, and bacterial invasion of human osteoblasts. Results Oxacillin, moxifloxacin and linezolid led to the development of a hyper-adhesive phenotype in the fibronectin adhesion assay that was consistent with an increase in fnbA/B transcription. Conversely, rifampin treatment decreased fibronectin binding in all strains tested without affecting fnbA/B transcription. Gentamicin and vancomycin had no impact on fibronectin binding or fnbA/B transcription levels. Only oxacillin-treated S. aureus displayed a significantly increased adhesion to cultured osteoblasts, but its invasiveness did not differ from that of untreated controls. Conclusion Our findings demonstrate that several antibiotics at sub-MICs modulate fibronectin binding in S. aureus in a drug-specific fashion. However, hyper- and hypo- adhesive phenotypes observed in controlled in vitro conditions were not fully confirmed in whole cell infection assays. The relevance of adhesion modulation during in vivo infections is thus still uncertain and requires further investigations.

  5. Invasive Disease Caused by Nontypeable Haemophilus Influenzae

    Centers for Disease Control (CDC) Podcasts

    2015-11-12

    Dr. Elizabeth Briere discusses Nontypeable Haemophilus influenzae which causes a variety of infections in children and adults.  Created: 11/12/2015 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 11/17/2015.

  6. The Lytic SA Phage Demonstrate Bactericidal Activity against Mastitis Causing Staphylococcus aureus

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    Hamza Ameer

    2016-01-01

    Full Text Available Staphylococcus aureus is the major causative agent of mastitis among dairy animals as it causes intramammary gland infection. Due to antibiotic resistance and contamination of antibiotics in the milk of diseased animals; alternative therapeutic agents are required to cure mastitis. Lytic bacteriophages and their gene products can be potential therapeutic agents against bacteria as they are host specific and less harmful than antibiotics. In this study, Staphylococcus aureus were isolated from milk samples of the infected animals and identified biochemically. SA phage was isolated from sewage water showing lytic activity against Staphylococcus aureus isolates. The highest lytic activity of bacteriophages was observed at 37°C and pH 7, and the most suitable storage condition was at 4°C. SA phage efficiently reduced bacterial growth in the bacterial reduction assay. The characterization and bacterial growth reduction activity of the bacteriophages against Staphylococcus aureus signifies their underlying potential of phage therapy against mastitis.

  7. Occurrence of enterotoxin-encoding genes in Staphylococcus aureus causing mastitis in lactating goats

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    Daneelly H. Ferreira

    2014-07-01

    Full Text Available Staphylococcal enterotoxins are the leading cause of human food poisoning worldwide. Staphylococcus spp. are the main mastitis-causing agents in goats and frequently found in high counts in goat milk. This study aimed to investigate the occurrence of enterotoxin-encoding genes in Staphylococcus aureus associated with mastitis in lactating goats in Paraiba State, Brazil. Milk samples (n=2024 were collected from 393 farms. Staphylococcus aureus was isolated in 55 milk samples. Classical (sea, seb, sec, sed, see and novel (seg, seh, sei enterotoxin-encoding genes were investigated by means of polymerase chain reaction (PCR. From thirty-six tested isolates, enterotoxin-encoding genes were detected in 7 (19.5% S. aureus. The gene encoding enterotoxin C (seC was identified in six isolates, while seiwas observed in only one isolate. The genes sea, seb, sed, see, seg and seh were not observed amongst the S. aureus investigated in this study. In summary, S. aureus causing mastitis in goats can harbor enterotoxin-encoding genes and seC was the most frequent gene observed amongst the investigated isolates. This finding is important for surveillance purposes, since enterotoxin C should be investigated in human staphylococcal food poisoning outbreaks caused by consumption of goat milk and dairy products.

  8. Novel Clones of Streptococcus pneumoniae Causing Invasive Disease in Malaysia

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    Johanna M Jefferies; Mohd Yasim Mohd Yusof; Shamala Devi Sekaran; Clarke, Stuart C.

    2014-01-01

    Although Streptococcus pneumoniae is a leading cause of childhood disease in South East Asia, little has previously been reported regarding the epidemiology of invasive pneumococcal disease in Malaysia and very few studies have explored pneumococcal epidemiology using multilocus sequence typing (MLST). Here we describe serotype, multilocus sequence type (ST), and penicillin susceptibility of thirty pneumococcal invasive disease isolates received by the University of Malaya Medical Centre betw...

  9. An Outbreak of Community-Acquired Foodborne Illness Caused by Methicillin-Resistant Staphylococcus aureus

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    Jones, Timothy F.; Kellum, Molly E.; Porter, Susan S.; Bell, Michael; Schaffner, William

    2002-01-01

    Infections with methicillin-resistant Staphylococcus aureus (MRSA) are increasingly community acquired. We investigated an outbreak in which a food handler, food specimen, and three ill patrons were culture positive for the same toxin-producing strain of MRSA. This is the first report of an outbreak of gastrointestinal illness caused by community-acquired MRSA.

  10. Immunomodulation and Disease Tolerance to Staphylococcus aureus

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    Zhigang Li; Peres, Adam G.; Andreea C. Damian; Joaquín Madrenas

    2015-01-01

    The Gram-positive bacterium Staphylococcus aureus is one of the most frequent pathogens that causes severe morbidity and mortality throughout the world. S. aureus can infect skin and soft tissues or become invasive leading to diseases such as pneumonia, endocarditis, sepsis or toxic shock syndrome. In contrast, S. aureus is also a common commensal microbe and is often part of the human nasal microbiome without causing any apparent disease. In this review, we explore the immunomodulation and d...

  11. Staphylococcus aureus seroproteomes discriminate ruminant isolates causing mild or severe mastitis

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    Le Maréchal Caroline

    2011-02-01

    Full Text Available Abstract Staphylococcus aureus is a major cause of mastitis in ruminants. In ewe mastitis, symptoms range from subclinical to gangrenous mastitis. S. aureus factors or host-factors contributing to the different outcomes are not completely elucidated. In this study, experimental mastitis was induced on primiparous ewes using two S. aureus strains, isolated from gangrenous (strain O11 or subclinical (strain O46 mastitis. Strains induced drastically distinct clinical symptoms when tested in ewe and mice experimental mastitis. Notably, they reproduced mild (O46 or severe (O11 mastitis in ewes. Ewe sera were used to identify staphylococcal immunoreactive proteins commonly or differentially produced during infections of variable severity and to define core and accessory seroproteomes. Such SERological Proteome Analysis (SERPA allowed the identification of 89 immunoreactive proteins, of which only 52 (58.4% were previously identified as immunogenic proteins in other staphylococcal infections. Among the 89 proteins identified, 74 appear to constitute the core seroproteome. Among the 15 remaining proteins defining the accessory seroproteome, 12 were specific for strain O11, 3 were specific for O46. Distribution of one protein specific for each mastitis severity was investigated in ten other strains isolated from subclinical or clinical mastitis. We report here for the first time the identification of staphylococcal immunogenic proteins common or specific to S. aureus strains responsible for mild or severe mastitis. These findings open avenues in S. aureus mastitis studies as some of these proteins, expressed in vivo, are likely to account for the success of S. aureus as a pathogen of the ruminant mammary gland.

  12. Memory Th1 Cells Are Protective in Invasive Staphylococcus aureus Infection.

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    Aisling F Brown

    Full Text Available Mechanisms of protective immunity to Staphylococcus aureus infection in humans remain elusive. While the importance of cellular immunity has been shown in mice, T cell responses in humans have not been characterised. Using a murine model of recurrent S. aureus peritonitis, we demonstrated that prior exposure to S. aureus enhanced IFNγ responses upon subsequent infection, while adoptive transfer of S. aureus antigen-specific Th1 cells was protective in naïve mice. Translating these findings, we found that S. aureus antigen-specific Th1 cells were also significantly expanded during human S. aureus bloodstream infection (BSI. These Th1 cells were CD45RO+, indicative of a memory phenotype. Thus, exposure to S. aureus induces memory Th1 cells in mice and humans, identifying Th1 cells as potential S. aureus vaccine targets. Consequently, we developed a model vaccine comprising staphylococcal clumping factor A, which we demonstrate to be an effective human T cell antigen, combined with the Th1-driving adjuvant CpG. This novel Th1-inducing vaccine conferred significant protection during S. aureus infection in mice. This study notably advances our understanding of S. aureus cellular immunity, and demonstrates for the first time that a correlate of S. aureus protective immunity identified in mice may be relevant in humans.

  13. Memory Th1 Cells Are Protective in Invasive Staphylococcus aureus Infection.

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    Brown, Aisling F; Murphy, Alison G; Lalor, Stephen J; Leech, John M; O'Keeffe, Kate M; Mac Aogáin, Micheál; O'Halloran, Dara P; Lacey, Keenan A; Tavakol, Mehri; Hearnden, Claire H; Fitzgerald-Hughes, Deirdre; Humphreys, Hilary; Fennell, Jérôme P; van Wamel, Willem J; Foster, Timothy J; Geoghegan, Joan A; Lavelle, Ed C; Rogers, Thomas R; McLoughlin, Rachel M

    2015-01-01

    Mechanisms of protective immunity to Staphylococcus aureus infection in humans remain elusive. While the importance of cellular immunity has been shown in mice, T cell responses in humans have not been characterised. Using a murine model of recurrent S. aureus peritonitis, we demonstrated that prior exposure to S. aureus enhanced IFNγ responses upon subsequent infection, while adoptive transfer of S. aureus antigen-specific Th1 cells was protective in naïve mice. Translating these findings, we found that S. aureus antigen-specific Th1 cells were also significantly expanded during human S. aureus bloodstream infection (BSI). These Th1 cells were CD45RO+, indicative of a memory phenotype. Thus, exposure to S. aureus induces memory Th1 cells in mice and humans, identifying Th1 cells as potential S. aureus vaccine targets. Consequently, we developed a model vaccine comprising staphylococcal clumping factor A, which we demonstrate to be an effective human T cell antigen, combined with the Th1-driving adjuvant CpG. This novel Th1-inducing vaccine conferred significant protection during S. aureus infection in mice. This study notably advances our understanding of S. aureus cellular immunity, and demonstrates for the first time that a correlate of S. aureus protective immunity identified in mice may be relevant in humans. PMID:26539822

  14. Memory Th1 Cells Are Protective in Invasive Staphylococcus aureus Infection.

    LENUS (Irish Health Repository)

    Brown, Aisling F

    2015-01-01

    Mechanisms of protective immunity to Staphylococcus aureus infection in humans remain elusive. While the importance of cellular immunity has been shown in mice, T cell responses in humans have not been characterised. Using a murine model of recurrent S. aureus peritonitis, we demonstrated that prior exposure to S. aureus enhanced IFNγ responses upon subsequent infection, while adoptive transfer of S. aureus antigen-specific Th1 cells was protective in naïve mice. Translating these findings, we found that S. aureus antigen-specific Th1 cells were also significantly expanded during human S. aureus bloodstream infection (BSI). These Th1 cells were CD45RO+, indicative of a memory phenotype. Thus, exposure to S. aureus induces memory Th1 cells in mice and humans, identifying Th1 cells as potential S. aureus vaccine targets. Consequently, we developed a model vaccine comprising staphylococcal clumping factor A, which we demonstrate to be an effective human T cell antigen, combined with the Th1-driving adjuvant CpG. This novel Th1-inducing vaccine conferred significant protection during S. aureus infection in mice. This study notably advances our understanding of S. aureus cellular immunity, and demonstrates for the first time that a correlate of S. aureus protective immunity identified in mice may be relevant in humans.

  15. Novel clones of Streptococcus pneumoniae causing invasive disease in Malaysia.

    Directory of Open Access Journals (Sweden)

    Johanna M Jefferies

    Full Text Available Although Streptococcus pneumoniae is a leading cause of childhood disease in South East Asia, little has previously been reported regarding the epidemiology of invasive pneumococcal disease in Malaysia and very few studies have explored pneumococcal epidemiology using multilocus sequence typing (MLST. Here we describe serotype, multilocus sequence type (ST, and penicillin susceptibility of thirty pneumococcal invasive disease isolates received by the University of Malaya Medical Centre between February 2000 and January 2007 and relate this to the serotypes included in current pneumococcal conjugate vaccines. A high level of diversity was observed; fourteen serotypes and 26 sequence types (ST, (11 of which were not previously described were detected from 30 isolates. Penicillin non-susceptible pneumococci accounted for 33% of isolates. The extent of molecular heterogeneity within carried and disease-causing Malaysian pneumococci remains unknown. Larger surveillance and epidemiological studies are now required in this region to provide robust evidence on which to base future vaccine policy.

  16. Clonal Structure and Characterization of Staphylococcus aureus Strains from Invasive Infections in Paediatric Patients from South Poland: Association between Age, spa Types, Clonal Complexes, and Genetic Markers.

    Science.gov (United States)

    Ilczyszyn, Weronika M; Sabat, Artur J; Akkerboom, Viktoria; Szkarlat, Anna; Klepacka, Joanna; Sowa-Sierant, Iwona; Wasik, Barbara; Kosecka-Strojek, Maja; Buda, Aneta; Miedzobrodzki, Jacek; Friedrich, Alexander W

    2016-01-01

    The aim of current study was to examine clonal structure and genetic profile of invasive Staphylococcus aureus isolates recovered from infants and children treated at the Jagiellonian University Children's Hospital of Krakow, Poland. The 107 invasive S. aureus isolates, collected between February 2012 and August 2014, were analysed retrospectively. Antimicrobial susceptibility testing, spa typing and DNA microarray analysis were performed to determine clonal distribution, diversity and gene content in regard to patients characteristics. In total, 107 isolates were recovered from 88 patients with clinical symptoms of invasive bacterial infection. The final set of 92 non-duplicate samples included 38 MRSA isolates. Additionally, a set of 54 S. aureus isolates collected during epidemiological screening was genotyped and analysed. There were 72 healthcare-associated (HCA) and 20 community-onset (CO) infection events caused by 33 and 5 MRSA isolates, respectively. The majority of isolates were affiliated with the major European clonal complexes CC5 (t003, spa-CC 002), CC45 (spa-CC 015), CC7 or CC15 (t084, t091, spa-CC 084). Two epidemic clones (CC5-MRSA-II or CC45-MRSA-IV) dominated among MRSA isolates, while MSSA population contained 15 different CCs. The epidemiological screening isolates belonged to similar genetic lineages as those collected from invasive infection cases. The HCA infection events, spa types t003, t2642 or CC5 were significantly associated with infections occurring in neonates and children under 5 years of age. Moreover, carriage of several genetic markers, including erm(A), sea (N315), egc-cluster, chp was significantly higher in isolates obtained from children in this age group. The spa types t091 and t008 were underrepresented among patients aged 5 years or younger, whereas spa type t008, CC8 and presence of splE was associated with infection in children aged 10 years or older. The HCA-MRSA strains were most frequently found in children under 5

  17. Mastitis in Ettawa Crossbred Goat (Pe) Caused by Staphylococcus Aureus: Epidemiology, Clinical Signs, Pathogenesis, Diagnosis and Control

    OpenAIRE

    Widodo Suwito; Indarjulianto S

    2016-01-01

    Mastitis in Ettawa crossbred goat is commonly found and caused economic loss. Staphylococcus aureus is one of bacteria caused clinical mastitis or subclinical mastitis in Ettawa crossbred goat. The aim of this review was to provide an overview of clinical and subclinical mastitis in the Ettawa crossbred goat caused by S. aureus from epidemiological aspect, clinical symptoms, pathogenesis, diagnosis, treatment, prevention and control. Mastitis should be eliminated because it lead to death for ...

  18. 金黄色葡萄球菌医院感染的临床分析%Clinical Analysis of Nosocomial Infection Caused by Staphylococcus Aureus

    Institute of Scientific and Technical Information of China (English)

    杨榕源; 叶小玲

    2015-01-01

    目的:分析由金黄色葡萄球菌导致的医院感染的临床特点和耐药特征。方法分析导致该院67例患者发生医院感染的危险因素及耐药特点,采用全自动细菌鉴定仪对分离的金黄色葡萄球菌菌株进行鉴定,采用纸片扩散法(K-B法)进行药物敏感性试验。结果67例医院感染患者共分离出75株金黄色葡萄球菌,其中包括61株耐甲氧西林金黄色葡萄球菌和14株甲氧西林敏感金黄色葡萄球菌。耐甲氧西林金黄色葡萄球菌的耐药性明显高于甲氧西林敏感金黄色葡萄球菌(P<0.05)。67例患者均存在严重的基础疾病,其中59例患者临床治疗接受过侵入性操作,发生感染的部位主要为肺部。结论金黄色葡萄球菌医院感染的发病群体主要为病情严重,接受过侵入性操作治疗的患者,感染部位主要为肺部,耐甲氧西林金黄色葡萄球菌对对数抗菌药物具有高耐药性。%Objective To analyze the clinical characteristics of nosocomial infections caused by Staphylococcus aureus and the resistance characteristics of Staphylococcus aureus.Methods The resistance characteristics of Staphylococcus aureus and the risk factors that caused the nosocomial infections in 67 patients of our hospital were analyzed. The automated bacterial identification system was used to identify separated Staphylococcus aureus strains. Drug sensitivity test was conducted by disk diffusion technique (K-B method).Results 75 Staphylococcus aureus were separated from 67 patients with nosocomial infections, including 61 methicillin-resistant Staphylococcus aureus and 14 methicillin-sensitive Staphylococcus aureus. Resistance of methicillin-resistant Staphylococcus aureus was significantly higher than that of methicillin-sensitive Staphylococcus aureus (P <0.05). Underlying diseases were found in 67 patients , among them, 59 patients with Pulmonary infection had received invasive operation during clinical

  19. Staphylococcus aureus host cell invasion and virulence in sepsis is facilitated by the multiple repeats within FnBPA.

    Directory of Open Access Journals (Sweden)

    Andrew M Edwards

    Full Text Available Entry of Staphylococcus aureus into the bloodstream can lead to metastatic abscess formation and infective endocarditis. Crucial to the development of both these conditions is the interaction of S. aureus with endothelial cells. In vivo and in vitro studies have shown that the staphylococcal invasin FnBPA triggers bacterial invasion of endothelial cells via a process that involves fibronectin (Fn bridging to alpha(5beta(1 integrins. The Fn-binding region of FnBPA usually contains 11 non-identical repeats (FnBRs with differing affinities for Fn, which facilitate the binding of multiple Fn molecules and may promote integrin clustering. We thus hypothesized that multiple repeats are necessary to trigger the invasion of endothelial cells by S. aureus. To test this we constructed variants of fnbA containing various combinations of FnBRs. In vitro assays revealed that endothelial cell invasion can be facilitated by a single high-affinity, but not low-affinity FnBR. Studies using a nisin-inducible system that controlled surface expression of FnBPA revealed that variants encoding fewer FnBRs required higher levels of surface expression to mediate invasion. High expression levels of FnBPA bearing a single low affinity FnBR bound Fn but did not invade, suggesting that FnBPA affinity for Fn is crucial for triggering internalization. In addition, multiple FnBRs increased the speed of internalization, as did higher expression levels of FnBPA, without altering the uptake mechanism. The relevance of these findings to pathogenesis was demonstrated using a murine sepsis model, which showed that multiple FnBRs were required for virulence. In conclusion, multiple FnBRs within FnBPA facilitate efficient Fn adhesion, trigger rapid bacterial uptake and are required for pathogenesis.

  20. Memory Th1 Cells Are Protective in Invasive Staphylococcus aureus Infection

    NARCIS (Netherlands)

    A.F. Brown (Aisling F.); A.G. Murphy (Alison G.); S.J. Lalor (Stephen J.); J.M. Leech (John M.); K.M. O’Keeffe (Kate M.); M. Mac Aogáin (Micheál); D.P. O’Halloran (Dara P.); K.A. Lacey (Keenan A.); M. Tavakol (Mehri); C.H. Hearnden (Claire H.); D. Fitzgerald-Hughes (Deirdre); H. Humphreys (Hilary); J.P. Fennell (Jérôme P.); W.J.B. van Wamel (Willem); T.J. Foster (Timothy J.); J.A. Geoghegan (Joan A.); E.C. Lavelle (Ed C.); T.R. Rogers (Thomas R.); R.M. McLoughlin (Rachel M.)

    2015-01-01

    textabstractMechanisms of protective immunity to Staphylococcus aureus infection in humans remain elusive. While the importance of cellular immunity has been shown in mice, T cell responses in humans have not been characterised. Using a murine model of recurrent S. aureus peritonitis, we demonstrate

  1. Successful Daptomycin Use in a Pediatric Patient With Acute, Bilateral Osteomyelitis Caused by Methicillin-Resistant Staphylococcus aureus

    OpenAIRE

    Billups, Kelsey L.; Stultz, Jeremy S

    2015-01-01

    Staphylococcus aureus is the most common bacteria associated with the development of osteomyelitis in pediatric patients. Osteomyelitis caused by methicillin-resistant Staphylococcus aureus (MRSA) can be difficult to safely and effectively treat. Vancomycin, linezolid, and clindamycin are commonly used to treat osteomyelitis caused by MRSA. While adult studies suggest intravenous (IV) daptomycin may by beneficial for the treatment of MRSA osteomyelitis, it is not Food and Drug Administration ...

  2. Combination Therapy of LysGH15 and Apigenin as a New Strategy for Treating Pneumonia Caused by Staphylococcus aureus.

    Science.gov (United States)

    Xia, Feifei; Li, Xin; Wang, Bin; Gong, Pengjuan; Xiao, Feng; Yang, Mei; Zhang, Lei; Song, Jun; Hu, Liyuan; Cheng, Mengjun; Sun, Changjiang; Feng, Xin; Lei, Liancheng; Ouyang, Songying; Liu, Zhi-Jie; Li, Xinwei; Gu, Jingmin; Han, Wenyu

    2015-10-16

    Pneumonia is one of the most prevalent Staphylococcus aureus-mediated diseases, and the treatment of this infection is becoming challenging due to the emergence of multidrug-resistant S. aureus, especially methicillin-resistant S. aureus (MRSA) strains. It has been reported that LysGH15, the lysin derived from phage GH15, displays high efficiency and a broad lytic spectrum against MRSA and that apigenin can markedly diminish the alpha-hemolysin of S. aureus. In this study, the combination therapy of LysGH15 and apigenin was evaluated in vitro and in a mouse S. aureus pneumonia model. No mutual adverse influence was detected between LysGH15 and apigenin in vitro. In animal experiments, the combination therapy showed a more effective treatment effect than LysGH15 or apigenin monotherapy (P pneumonia caused by MRSA. This paper reports the combination therapy of lysin and natural products derived from traditional Chinese medicine.

  3. Immunomodulation and Disease Tolerance to Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Zhigang Li

    2015-11-01

    Full Text Available The Gram-positive bacterium Staphylococcus aureus is one of the most frequent pathogens that causes severe morbidity and mortality throughout the world. S. aureus can infect skin and soft tissues or become invasive leading to diseases such as pneumonia, endocarditis, sepsis or toxic shock syndrome. In contrast, S. aureus is also a common commensal microbe and is often part of the human nasal microbiome without causing any apparent disease. In this review, we explore the immunomodulation and disease tolerance mechanisms that promote commensalism to S. aureus.

  4. Central venous catheter-related bloodstream infection caused by Staphylococcus aureus: microbiology and risk factors

    Directory of Open Access Journals (Sweden)

    Geraldo Sadoyma

    2006-04-01

    Full Text Available Although central vascular catheters (CVC are indispensable in modern medicine, they are an important risk factor for primary bacteremias. We examined the incidence and risk factors associated with catheter-related bloodstream infection (CR-BSI caused by Staphylococcus aureus in surgical patients. A prospective study was carried out in the Hospital das Clínicas da Universidade Federal de Uberlândia (HC-UFU from September 2000 to December 2002. The skin insertion site, catheter tip, and blood were microbiologically analyzed. Demographics and risk factors were recorded for each patient, and cultures were identified phenotypically. Staphylococcus aureus was the most frequent pathogen, with an incidence rate of 4.9 episodes of CR-BSIs per 1,000 catheter/days. Based on logistic regression, the independent risk factors were: colonization on the insertion site =200 colony forming units (CFU/20 cm² (p=0.03; odds ratio (OR =6.89 and catheter tip (p=0.01; OR=7.95. The CR-BSI rate was high; it was mainly associated with S. aureus, and skin colonization at the insertion site and on the catheter tip were important risk factors for CR-BSI.

  5. Preliminary treatment of bovine mastitis caused by Staphylococcus aureus, with trx-SA1, recombinant endolysin of S. aureus bacteriophage IME-SA1.

    Science.gov (United States)

    Fan, Jindai; Zeng, Zhiliang; Mai, Kaijie; Yang, Yu; Feng, Jiaqi; Bai, Yang; Sun, Baoli; Xie, Qingmei; Tong, Yigang; Ma, Jingyun

    2016-08-15

    Methicillin-resistant Staphylococcus aureus (MRSA) has become a great threat to human and animal health and there is an urgent need to develop novel antibacterial agents to control this pathogen. The objective of this study was to obtain an active recombinant endolysin from the novel bacteriophage (IME-SA1), and conduct an efficacy trial of its effectiveness against bovine mastitis. We isolated a phage that was virulent and specific for S. aureus with an optimal multiplicity of infection of 0.01. Electron microscopy revealed that IME-SA1 was a member of the family Myoviridae, with an isometric head (98nm) and a long contractile tail (200nm). Experimental lysis experiments indicated the phage had an incubation period of 20min with a burst size of 80. When host bacteria were in early exponential growth stages, a multiplicity of infection of 0.01 resulted in a complete bacterial lysis after 9h. The endolysin gene (804bp) was cloned into the pET-32a bacterial expression vector and recombinant endolysin Trx-SA1 was successfully obtained with molecular size of about 47kDa. Preliminary results of therapeutic trials in cow udders showed that Trx-SA1 could effectively control mild clinical mastitis caused by S. aureus. The endolysin Trx-SA1 might be an alternative treatment strategy for infections caused by S. aureus, including MRSA. PMID:27374909

  6. Efficacy of oxacillin and ampicillin-sulbactam combination in experimental endocarditis caused by beta-lactamase-hyperproducing Staphylococcus aureus.

    OpenAIRE

    Thauvin-Eliopoulos, C; Rice, L B; Eliopoulos, G M; Moellering, R C

    1990-01-01

    Optimal therapy of infections caused by borderline oxacillin-susceptible, beta-lactamase-hyperproducing Staphylococcus aureus has not been established. We used a rat model of aortic valve endocarditis to examine efficacies of antibiotic regimens against a borderline oxacillin-susceptible strain as compared with a fully susceptible S. aureus strain. Animals were treated with oxacillin alone or in combination with sulbactam or with ampicillin-sulbactam combinations at two dose levels. Infection...

  7. The Climate change caused by the land-plants invasion

    Science.gov (United States)

    Le Hir, G.; Godderis, Y.; Meyer-Berthaud, B.; Donnadieu, Y.; Ramstein, G.

    2009-04-01

    Land-plants invaded continents during the Mid-Paleozoic. Their spreading and diversification have been compared to the Cambrian explosion in terms of intensity and importance in the Earth life history. If prior studies were focused on the roots system development and its weathering impact, here we used a coupled climate/carbon/vegetation model to investigate impacts of their colonization on surface climate. The simulated climate predicts a significant CO2 drawdown due to an enhanced hydrological cycle which is paradoxically associated with a very small temperature change. Indeed the greenhouse reduction linked to CO2 is counter-acted by a large warming provided by the surface albedo reduction caused by the appearance of an extended plant-cover. If the CO2 is consensually assumed as the main driver of the Phanerozoic climate, this paper demonstrates that, during the land-plants invasion, the soil properties modifications have supplanted the carbon as the primary factor governing the climate.

  8. Improving Diagnosis and Treatment of Staphylococcus aureus Infections : Experimental Studies

    NARCIS (Netherlands)

    S. van den Berg (Sanne)

    2015-01-01

    markdownabstract__Abstract__ Staphylococcus aureus is an opportunistic pathogen that causes a variety of infections, ranging from mild skin infections like furuncles and impetigo, to severe, lifethreatening infections including endocarditis, osteomyelitis and pneumonia. Invasive infections are freq

  9. Risk factors assessment for nasal colonization of Staphylococcus aureus and its methicillin resistant strains among pre-clinical medical students of Nepal

    OpenAIRE

    Ansari, Shamshul; Gautam, Rajendra; Shrestha, Sony; Ansari, Safiur Rahman; Subedi, Shankar Nanda; Chhetri, Muni Raj

    2016-01-01

    Background Staphylococcus aureus (S. aureus), a normal flora of nasal cavity, can cause minor to life threatening invasive diseases and nosocomial infections. Methicillin resistant strains of S. aureus are causing a great challenge for treatment options. Therefore, the purpose of this study was to assess the nasal carriage rate of S. aureus, its methicillin resistant strains and risk factors in medical students prior to clinical exposure. Methods The bacterial growth of S. aureus from nasal s...

  10. Mastitis in Ettawa Crossbred Goat (Pe Caused by Staphylococcus Aureus: Epidemiology, Clinical Signs, Pathogenesis, Diagnosis and Control

    Directory of Open Access Journals (Sweden)

    Widodo Suwito

    2016-02-01

    Full Text Available Mastitis in Ettawa crossbred goat is commonly found and caused economic loss. Staphylococcus aureus is one of bacteria caused clinical mastitis or subclinical mastitis in Ettawa crossbred goat. The aim of this review was to provide an overview of clinical and subclinical mastitis in the Ettawa crossbred goat caused by S. aureus from epidemiological aspect, clinical symptoms, pathogenesis, diagnosis, treatment, prevention and control. Mastitis should be eliminated because it lead to death for the goats and lambs. In addition, S. aureus has greater risk for contamination in milk because it produces heat-stable toxin. Isolation and identification bacteria with total of somatic cell counts are important as a reference to determine the actions to decrease the occurrence of mastitis. Some preventive measures for mastitis include clean milking, dipping the teats with a disinfectant and antibiotic treatment during dry lactation.

  11. Serum antibodies against Staphylococcus aureus antigens in healthy individuals and patients with invasive infections

    OpenAIRE

    Colque-Navarro, Patricia

    2010-01-01

    The present work aims to study the antibody responses against Staphylococcus aureus in health and in deep infections and is composed of six papers. We developed a sandwich enzyme immuno assay (EIA) with a detection limit for alpha-toxin at nanograms levels. This method is applicable to measure alpha-toxin in culture supernatants and in human fluids. The assay is simple, reproducible and performed within 6 hours. We determined the presence of alpha-toxin in serum samples ...

  12. Invasive mole: a rare cause of postmenopausal bleeding

    Directory of Open Access Journals (Sweden)

    Mamour Guèye

    2013-06-01

    Full Text Available Gestational trophoblastic disease (GTD describes a number of gynaecological tumours that originate in the trophoblast layer, including hydatidiform mole (complete or partial, placental site trophoblastic tumour, choriocarcinoma and invasive mole. Invasive moles are responsible of most cases of localized gestational trophoblastic neoplasia (GTN. Invasive mole is a condition where a molar pregnancy, such as a partial hydatidiform mole or complete hydatidiform mole, invades the wall of the uterus. It is an extremely rare condition. As GTN is not considered in the differential diagnosis of postmenopausal uterine malignancies, its preoperative diagnosis is challenging. We report a case of invasive hydatidiform mole in a postmenopausal woman discovered in a context of postmenopausal bleeding. She underwent hysterectomy and followed up till her beta hCG levels were within normal limits. The patient is in complete remission in the first postoperative year. [Int J Reprod Contracept Obstet Gynecol 2013; 2(3.000: 451-453

  13. Outbreaks of Infection Caused by Community-Acquired Methicillin-Resistant Staphylococcus aureus in a Canadian Correctional Facility

    Directory of Open Access Journals (Sweden)

    Cheryl L Main

    2005-01-01

    Full Text Available BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA has been identified in prison settings in the United States. The present study investigated two clusters of skin and soft tissue infection caused by community-acquired (CA MRSA in a correctional facility in southern Ontario.

  14. Chimeric phage lysins act synergistically with lysostaphin to kill mastitis causing staphylococcus aureus in murine mammary glands

    Science.gov (United States)

    Staphylococci cause bovine mastitis with Staphylococcus aureus being responsible for the majority of the mastitis-based losses to the dairy industry (up to $2 billion/annum). Treatment is primarily with antibiotics that are often ineffective and potentially contribute to resistance development. Bac...

  15. Invasive pulmonary aspergillosis caused by Aspergillus versicolor in a patient on mechanical ventilation

    OpenAIRE

    MV Pravin Charles; M Ravishankar; Easow, Joshy M; Noyal Mariya Joseph

    2011-01-01

    Aspergillus spp. often colonise the respiratory tract of critically ill patients in intensive care units and subsequently cause invasive disease. The risk of developing invasive disease is more in immunocompromised patients. Here we report a case of fatal invasive pulmonary aspergillosis caused by Aspergillus versicolor in a post-operative patient on mechanical ventilation, who did not respond to intravenous itraconazole. We then discuss the challenges involved in the accurate diagnosis of th...

  16. Chorioamnionitis caused by Staphylococcus aureus with intact membranes in a term pregnancy: A case of maternal and fetal septic shock.

    Science.gov (United States)

    Sorano, Sumire; Goto, Maki; Matsuoka, Sakiko; Tohyama, Atsushi; Yamamoto, Hiroko; Nakamura, Sumie; Fukami, Tatsuya; Matsuoka, Ryoei; Tsujioka, Hiroshi; Eguchi, Fuyuki

    2016-04-01

    Chorioamnionitis is usually caused by migration of cervicovaginal flora through the cervical canal in women with ruptured membranes. Common causative pathogens are genital mycoplasmas, anaerobes, enteric gram-negative bacilli, and group B streptococcus. There have been only seven previous reports of chorioamnionitis due to Staphylococcus aureus and their clinical courses are characterized by rapid disease progression and poor prognosis. This case report describes a case of acute chorioamnionitis due to S. aureus, which was successfully managed with immediate cesarean section and postoperative intensive care. A 22-year-old woman presented at 39 weeks' gestation with a fever and acute lower abdominal pain. Fetal heart monitoring showed fetal distress. Immediate cesarean delivery was performed under general anesthesia. A male infant weighing 2450 g was born. He had Apgar scores of 3 and 7 at 1 and 5 min, respectively. He was immediately intubated and admitted to the neonatal intensive care unit. Maternal blood culture, vaginal culture, neonatal nares, and blood and gastric fluid culture all showed methicillin-sensitive S. aureus. Histopathology of the placenta demonstrated focal acute funisitis and acute chorioamnionitis. Interestingly, most of the patients in the previous reports developed chorioamnionitis due to S. aureus despite the presence of intact membranes, as in our case. Bacterial spread in the absence of membrane rupture and the presence of bacteremia suggests hematogenous, rather than ascending, etiology of S. aureus chorioamnionitis. PMID:26705749

  17. Invasive alien predator causes rapid declines of native European ladybirds

    DEFF Research Database (Denmark)

    Roy, Helen E.; Adriaens, Tim; Isaac, Nick J.B.;

    2012-01-01

    Aim Invasive alien species (IAS) are recognized as major drivers of biodiversity loss, but few causal relationships between IAS and species declines have been documented. In this study, we compare the distribution (Belgium and Britain) and abundance (Belgium, Britain and Switzerland) of formerly...

  18. Another cause of chest pain: Staphylococcus aureus sternal osteomyelitis in an otherwise healthy adult

    Directory of Open Access Journals (Sweden)

    Vacek TP

    2014-09-01

    Full Text Available Thomas P Vacek, Shahnaz Rehman, Shipeng Yu, Ankush Moza, Ragheb Assaly Department of Internal Medicine, The University of Toledo Medical Center, Toledo OH, USAAbstract: Chest pain requires a detailed differential diagnosis with good history-taking skills to differentiate between cardiogenic and noncardiogenic causes. Moreover, when other symptoms such as fever and elevated white blood cell count are involved, it may be necessary to consider causes that include infectious sources. A 53-year-old female with no significant past medical history returned to the hospital with recurrent complaints of chest pain that was constant, substernal, reproducible, and exacerbated with inspiration and expiration. The chest pain was thought to be noncardiogenic, as electrocardiography did not demonstrate changes, and cardiac enzymes were found to be negative for signs of ischemia. The patient's blood cultures were analyzed from a previous admission and were shown to be positive for Staphylococcus aureus. The patient was started empirically on vancomycin, which was later switched to ceftriaxone as the bacteria were more sensitive to this antibiotic. A transthoracic echocardiogram did not demonstrate any vegetation or signs of endocarditis. There was a small right pleural effusion discovered on X-ray. Therefore, computed tomography as well as magnetic resonance imaging of the chest were performed, and showed osteomyelitis of the chest. The patient was continued on intravenous ceftriaxone for a total of 6 weeks. Tests for HIV, hepatitis A, B, and C were all found to be negative. The patient had no history of childhood illness, recurrent infections, or previous trauma to the chest, and had had no recent respiratory infections, pneumonia, or any underlying lung condition. Hence, her condition was thought to be a case of primary sternal osteomyelitis without known cause.Keywords: substernal, pleuritic, myocardial infarction, differential

  19. Invasive alien predator causes rapid declines of native European ladybirds

    OpenAIRE

    Roy, Helen E; Adriaens, Tim; Isaac, Nick J. B.; Kenis, Marc; Onkelinx, Thierry; Martin, Gilles San; Brown, Peter M. J.; Hautier, Louis; Poland, Remy; Roy, David B.; Comont, Richard; Eschen, René; Frost, Robert; Zindel, Renate; Vlaenderen, Johan Van

    2012-01-01

    Aim  Invasive alien species (IAS) are recognized as major drivers of biodiversity loss, but few causal relationships between IAS and species declines have been documented. In this study, we compare the distribution (Belgium and Britain) and abundance (Belgium, Britain and Switzerland) of formerly common and widespread native ladybirds before and after the arrival of Harmonia axyridis, a globally rapidly expanding IAS.Location  EuropeMethods  We used generalized linear mixed-effects models (GL...

  20. Molecular Typing of Mastitis-Causing Staphylococcus aureus Isolated from Heifers and Cows

    Directory of Open Access Journals (Sweden)

    Juliana Rodrigues Pozzi Arcaro

    2013-02-01

    Full Text Available Staphylococcus aureus is among the main etiologic agents of bovine mastitis. A total of 83 isolates of S. aureus from mammary glands of primiparous heifers were collected in the prepartum, calving and during lactation. For lactating cows, a total of 27 isolates of S. aureus from mammary glands were collected during lactation. The samples were taken in two dairy farms located in Sao Paulo State, Brazil. The highest frequency of S. aureus isolation in heifers was at the end of lactation. Strains were typified through Pulsed-field gel electrophoresis (PFGE and grouped according to patterns of restriction enzyme SmaI. PFGE generated seven clonal profiles that were grouped into three different lineages, with the LA lineage being predominant and identified in heifers, as well as in the cows from the two regions studied. It was concluded that the cows showed a significant source of dispersion of S. aureus. At the first lactation the heifers were infected by the same clonal profiles of S. aureus which were isolated from multiparous lactating cows. The heifers were infected during milking over the months of lactation.

  1. Interleukin-33 facilitates neutrophil recruitment and bacterial clearance in S. aureus-caused peritonitis.

    Science.gov (United States)

    Lan, Fang; Yuan, Baohong; Liu, Tao; Luo, Xiaochun; Huang, Ping; Liu, Yunjun; Dai, Liangcheng; Yin, Hui

    2016-04-01

    Interleukin (IL)-33, a newly recognized member of IL-1 family of cytokines, plays an important role in polarizing Th2-associated immunity. Recently growing evidence indicates that IL-33 also represents a crucial mediator of antimicrobial infection. In this study, we investigated the effect of IL-33 on antibacterial response using an acute Staphylococcus aureus peritoneal infection model. Our results showed that IL-33 administration induced a rapid bacterial clearance and markedly reduced the S. aureus infection-related mortality. IL-33-treated mice displayed increased neutrophil influx into the focus of infection and higher concentrations of chemokine CXCL2 in the peritoneum than untreated mice. The beneficial effect of IL-33 priming was related to reversal of the S. aureus-induced reduction of CXCR2 expression on the surface of neutrophils. Furthermore, conditioning of neutrophils by IL-33 led to the enhancement of complement receptor 3 expression induced by S. aureus, which in turn facilitates the phagocytosis of opsonized S. aureus. Finally, neutrophils primed by IL-33 upregulated the production of reactive oxygen species and the subsequent killing activity for S. aureus. All together, these findings suggest that IL-33, through regulating multiple steps of neutrophil-mediated bactericidal function, provides a profound effect in host antimicrobial defense response.

  2. Identification of Infantile Diarrhea Caused by Breast Milk-Transmitted Staphylococcus aureus Infection.

    Science.gov (United States)

    Chen, Zhong; Pan, Wei-Guang; Xian, Wei-Yi; Cheng, Hang; Zheng, Jin-Xin; Hu, Qing-Hua; Yu, Zhi-Jian; Deng, Qi-Wen

    2016-10-01

    Staphylococcus aureus is a well-known organism which is responsible for a variety of human infectious diseases including skin infections, pneumonia, bacteremia, and endocarditis. Few of the microorganisms can be transmitted from mother to the newborn or infant by milk breastfeeding. This study aims to identify transmission of S. aureus from healthy, lactating mothers to their infants by breastfeeding. Stool specimens of diarrheal infants and breast milk of their mother (totally three pairs) were collected and six Staphylococcus aureus isolates were cultured positively. Homology and molecular characters of isolated strains were tested using pulsed-field gel electrophoresis (PFGE), spa typing, and multilocus sequence typing. Furthermore, toxin genes detection was also performed. Each pair of isolates has the same PFGE type and spa type. Four Sequence types (STs) were found among all the isolates; they are ST15, ST188, and ST59, respectively. Among the strains, seb, sec, and tst genes were found, and all were negative for pvl gene. The homology of the S. aureus strains isolated from the infants' stool and the mothers' milk was genetically demonstrated, which indicated that breastfeeding may be important in the transmission of S. aureus infection, and the character of S. aureus needed to be further evaluated. PMID:27344596

  3. Invasive Community-Acquired Methicillin-Resistant Staphylococcus aureus in a Japanese Girl with Disseminating Multiple Organ Infection: A Case Report and Review of Japanese Pediatric Cases

    OpenAIRE

    Ryuta Yonezawa; Tsukasa Kuwana; Kengo Kawamura; Yasuji Inamo

    2015-01-01

    Pediatric invasive community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) infection is very serious and occasionally fatal. This infectious disease is still a relatively rare and unfamiliar infectious disease in Japan. We report a positive outcome in a 23-month-old Japanese girl with meningitis, osteomyelitis, fasciitis, necrotizing pneumonia, urinary tract infection, and bacteremia due to CA-MRSA treated with linezolid. PCR testing of the CA-MRSA strain was positive for PVL...

  4. Host-specificity of Staphylococcus aureus causing intramammary infections in dairy animals assessed by genotyping and virulence genes.

    Science.gov (United States)

    Bar-Gal, G Kahila; Blum, S E; Hadas, L; Ehricht, R; Monecke, S; Leitner, G

    2015-03-23

    Staphylococcus aureus is one of the most relevant pathogens causing clinical and subclinical, chronic mastitis in dairy animals. Routinely, mastitis pathogens are isolated and classified to genus or species level, and regarded as single entities. However, S. aureus includes a broad range of genotypes with distinct pathogenic and epidemiologic characteristics. The objective of the present study was to assess the host-specificity of S. aureus causing mastitis in dairy animals, based on phylogenetic and genotypic characterization as well as the presence of virulence and antimicrobial resistance genes in the pathogen genome. S. aureus isolates from mastitis in cows, sheep and goats in Israel, and from cows in Germany, the USA and Italy, were compared by the following methods: a. Bayesian phylogenetic comparison of sequences of genes nuc, coa, lukF and clfA, b. genotyping by spa and agr typing, and assignment to MLST Clonal Complexes (MLST CC), and c. the presence of a broad array of virulence and antimicrobial resistance genes. Overall, phylogenetic, virulence and genotyping approaches agreed with each other. Cow isolates could be differentiated from sheep and goat isolates with all three methods, with different resolution. In two phylogenetic clusters, segregation was found also between cow isolates from Israel and abroad. Sheep and goats' isolates showed less variability than isolates from cows in all methods used. In conclusion, different S. aureus lineages are associated to cows in contrast to goats and sheep, suggesting co-evolution between pathogen and host species. Modern diagnostics approaches should aim to explore molecular data for a better understanding and cost-effective management of mastitis. PMID:25631254

  5. Whole-Genome Sequencing for Routine Pathogen Surveillance in Public Health: a Population Snapshot of Invasive Staphylococcus aureus in Europe

    Science.gov (United States)

    Aanensen, David M.; Feil, Edward J.; Holden, Matthew T. G.; Dordel, Janina; Yeats, Corin A.; Fedosejev, Artemij; Goater, Richard; Castillo-Ramírez, Santiago; Corander, Jukka; Colijn, Caroline; Chlebowicz, Monika A.; Schouls, Leo; Heck, Max; Pluister, Gerlinde; Ruimy, Raymond; Kahlmeter, Gunnar; Åhman, Jenny; Matuschek, Erika; Friedrich, Alexander W.; Bentley, Stephen D.; Spratt, Brian G.

    2016-01-01

    ABSTRACT The implementation of routine whole-genome sequencing (WGS) promises to transform our ability to monitor the emergence and spread of bacterial pathogens. Here we combined WGS data from 308 invasive Staphylococcus aureus isolates corresponding to a pan-European population snapshot, with epidemiological and resistance data. Geospatial visualization of the data is made possible by a generic software tool designed for public health purposes that is available at the project URL (http://www.microreact.org/project/EkUvg9uY?tt=rc). Our analysis demonstrates that high-risk clones can be identified on the basis of population level properties such as clonal relatedness, abundance, and spatial structuring and by inferring virulence and resistance properties on the basis of gene content. We also show that in silico predictions of antibiotic resistance profiles are at least as reliable as phenotypic testing. We argue that this work provides a comprehensive road map illustrating the three vital components for future molecular epidemiological surveillance: (i) large-scale structured surveys, (ii) WGS, and (iii) community-oriented database infrastructure and analysis tools. PMID:27150362

  6. Whole-Genome Sequencing for Routine Pathogen Surveillance in Public Health: a Population Snapshot of Invasive Staphylococcus aureus in Europe

    Directory of Open Access Journals (Sweden)

    David M. Aanensen

    2016-05-01

    Full Text Available The implementation of routine whole-genome sequencing (WGS promises to transform our ability to monitor the emergence and spread of bacterial pathogens. Here we combined WGS data from 308 invasive Staphylococcus aureus isolates corresponding to a pan-European population snapshot, with epidemiological and resistance data. Geospatial visualization of the data is made possible by a generic software tool designed for public health purposes that is available at the project URL (http://www.microreact.org/project/EkUvg9uY?tt=rc. Our analysis demonstrates that high-risk clones can be identified on the basis of population level properties such as clonal relatedness, abundance, and spatial structuring and by inferring virulence and resistance properties on the basis of gene content. We also show that in silico predictions of antibiotic resistance profiles are at least as reliable as phenotypic testing. We argue that this work provides a comprehensive road map illustrating the three vital components for future molecular epidemiological surveillance: (i large-scale structured surveys, (ii WGS, and (iii community-oriented database infrastructure and analysis tools.

  7. DNA microarray analysis of Staphylococcus aureus causing bloodstream infection: bacterial genes associated with mortality?

    Science.gov (United States)

    Blomfeldt, A; Aamot, H V; Eskesen, A N; Monecke, S; White, R A; Leegaard, T M; Bjørnholt, J V

    2016-08-01

    Providing evidence for microbial genetic determinants' impact on outcome in Staphylococcus aureus bloodstream infections (SABSI) is challenging due to the complex and dynamic microbe-host interaction. Our recent population-based prospective study reported an association between the S. aureus clonal complex (CC) 30 genotype and mortality in SABSI patients. This follow-up investigation aimed to examine the genetic profiles of the SABSI isolates and test the hypothesis that specific genetic characteristics in S. aureus are associated with mortality. SABSI isolates (n = 305) and S. aureus CC30 isolates from asymptomatic nasal carriers (n = 38) were characterised by DNA microarray analysis and spa typing. Fisher's exact test, least absolute shrinkage and selection operator (LASSO) and elastic net regressions were performed to discern within four groups defined by patient outcome and characteristics. No specific S. aureus genetic determinants were found to be associated with mortality in SABSI patients. By applying LASSO and elastic net regressions, we found evidence suggesting that agrIII and cna were positively and setC (=selX) and seh were negatively associated with S. aureus CC30 versus non-CC30 isolates. The genes chp and sak, encoding immune evasion molecules, were found in higher frequencies in CC30 SABSI isolates compared to CC30 carrier isolates, indicating a higher virulence potential. In conclusion, no specific S. aureus genes were found to be associated with mortality by DNA microarray analysis and state-of-the-art statistical analyses. The next natural step is to test the hypothesis in larger samples with higher resolution methods, like whole genome sequencing. PMID:27177754

  8. Evaluation of non-invasive biological samples to monitor Staphylococcus aureus colonization in great apes and lemurs.

    Directory of Open Access Journals (Sweden)

    Frieder Schaumburg

    Full Text Available INTRODUCTION: Reintroduction of endangered animals as part of conservational programs bears the risk of importing human pathogens from the sanctuary to the natural habitat. One bacterial pathogen that serves as a model organism to analyze this transmission is Staphylococcus aureus as it can colonize and infect both humans and animals. The aim of this study was to evaluate the utility of various biological samples to monitor S. aureus colonization in great apes and lemurs. METHODS: Mucosal swabs from wild lemurs (n=25, Kirindy, Madagascar, feces, oral and genital swabs from captive chimpanzees (n=58, Ngamba and Entebbe, Uganda and fruit wadges and feces from wild chimpanzees (n=21, Taï National Parc, Côte d'Ivoire were screened for S. aureus. Antimicrobial resistance and selected virulence factors were tested for each isolate. Sequence based genotyping (spa typing, multilocus sequence typing was applied to assess the population structure of S. aureus. RESULTS: Oro-pharyngeal carriage of S. aureus was high in lemurs (72%, n=18 and captive chimpanzees (69.2%, n=27 and 100%, n=6, respectively. Wild chimpanzees shed S. aureus through feces (43.8, n=7 and fruit wadges (54.5, n=12. Analysis of multiple sampling revealed that two samples are sufficient to detect those animals which shed S. aureus through feces or fruit wadges. Genotyping showed that captive animals are more frequently colonized with human-associated S. aureus lineages. CONCLUSION: Oro-pharyngeal swabs are useful to screen for S. aureus colonization in apes and lemurs before reintroduction. Duplicates of stool and fruit wadges reliably detect S. aureus shedding in wild chimpanzees. We propose to apply these sampling strategies in future reintroduction programs to screen for S. aureus colonization. They may also be useful to monitor S. aureus in wild populations.

  9. Prevalence and Characterization of Oxacillin Susceptible mecA-Positive Clinical Isolates of Staphylococcus aureus Causing Bovine Mastitis in India

    Science.gov (United States)

    Mistry, Hiral; Sharma, Paresh; Mahato, Sudipta; Saravanan, R.; Kumar, P. Anand; Bhandari, Vasundhra

    2016-01-01

    Bovine mastitis caused by multidrug resistant Staphylococcus aureus is a huge problem reported worldwide, resulting in prolonged antibiotic treatment and death of livestock. The current study is focused on surveillance of antibiotic susceptibility along with genotypic and phenotypic characterization of the pathogenic S. aureus strains causing mastitis in India. One hundred and sixty seven milk samples were collected from mastitis-affected cows from different farms in India resulting in thirty nine isolated S. aureus strains. Antibiotic sensitivity profiling revealed the majority of the strains (n = 24) to be multidrug resistant and eleven strains showed reduced susceptibility to vancomycin (MICs = 2μg/ml). All strains were oxacillin sensitive, but 19 strains were positive for the mecA gene, which revealed the occurrence of oxacillin susceptible mecA positive strains (OS-MRSA) for the first time from India. Additionally, 32 strains were positive for the pvl gene, a virulence determinant; of these 17 were also OS-MRSA strains. Molecular characterization based on multilocus sequence typing (MLST), spa typing, agr typing and SCCmec classification revealed strains belonging to different groups. Moreover, strains showed spa types (t2526, t9602) and MLST sequence types, ST-72, ST-88 and ST-239 which have been earlier reported in human infections. The prevalence of OS-MRSA strains indicates the importance of including both the genetic and phenotypic tests in characterizing S. aureus strains. Increased genotypic variability with strain related to human infections and pvl positive isolates indicates a worrisome situation with the possibility of bilateral transfer. PMID:27603123

  10. Vertebral osteomyelitis caused by vancomycin-tolerant methicillin-resistant Staphylococcus aureus bacteremia: Experience with teicoplanin plus fosfomycin combination therapy.

    Science.gov (United States)

    Lee, Wen-Sen; Chen, Yen-Chuo; Chen, Hung-Ping; Chen, Tso-Hsiao; Cheng, Chung-Yi

    2016-08-01

    An 85-year-old female presented with fever and consciousness disturbance for 3 days. The patient's blood culture subsequently revealed persistent methicillin-resistant Staphylococcus aureus (MRSA) bacteremia despite the administration of vancomycin or teicoplanin monotherapy. Gallium inflammation scan and magnetic resonance image of the spine disclosed osteomyelitis and discitis at the level of L4-5. Surgical debridement was not feasible in this debilitated patient. Because of the creeping minimal inhibitory concentration of vancomycin of the causative isolate (1.5 μg/mL) and clinical failure with glycopeptide monotherapy, we changed the antibiotic therapy to a fosfomycin and teicoplanin combination therapy. The patient showed improved clinical response in terms of her enhanced consciousness as well as subsidence of persisted bacteremia. Despite the potential side effects of fosfomycin (such as diarrhea and hypernatremia), it combined with a glycopeptide may be an alternative therapy for invasive refractory MRSA infections. PMID:24269007

  11. Long-term mortality and causes of death associated with Staphylococcus aureus bacteremia. A matched cohort study

    DEFF Research Database (Denmark)

    Gotland, Nanja; Uhre, Marie-Louise; Mejer, N;

    2016-01-01

    respiratory disease, nervous system disease, unknown causes, psychiatric disorders, cardiovascular disease and senility. Over time, rates of death decreased or were stable for all disease categories except for musculoskeletal and skin disease where a trend towards an increase was seen. CONCLUSION: Long......-term mortality after SAB was high but decreased over time. SAB cases were more likely to die of eight specific causes of death and less likely to die of five other causes of death compared to controls. Causes of death decreased for most disease categories. Risk factors associated with long-term mortality were......OBJECTIVES: Data describing long-term mortality in patients with Staphylococcus aureus bacteremia (SAB) is scarce. This study investigated risk factors, causes of death and temporal trends in long-term mortality associated with SAB. METHODS: Nationwide population-based matched cohort study...

  12. Successful treatment of an invasive fungal infection caused by Talaromyces sp. with voriconazole

    OpenAIRE

    Uluhan Sili; Huseyin Bilgin; Rikesh Masania; Emel Eryuksel; Nuri Cagatay Cimsit; Gulcicek Ayranci; Malcolm Richardson; Volkan Korten

    2015-01-01

    Invasive fungal infections (IFI) are on the rise due to increasing numbers of immunosuppressed and critically ill patients. A malignant-looking pulmonary nodule in an immunosuppressed patient may indeed be caused by a fungal organism. We report a patient, who was eventually diagnosed with an IFI caused by an agent of hyalohyphomycosis, Talaromyces sp. determined via molecular methods and succesfully treated with voriconazole.

  13. High-dose daptomycin and fosfomycin treatment of a patient with endocarditis caused by daptomycin-nonsusceptible Staphylococcus aureus: Case report

    Directory of Open Access Journals (Sweden)

    Hsiao Chen-Yuan

    2011-05-01

    Full Text Available Abstract Background Emergence of daptomycin-nonsusceptible (DNS Staphylococcus aureus is a dreadful problem in the treatment of endocarditis. Few current therapeutic agents are effective for treating infections caused by DNS S. aureus. Case presentation We describe the emergence of DNS S. aureus. in a patient with implantable cardioverter-defibrillator (ICD device -related endocarditis who was priorily treated with daptomycin. Metastatic dissemination as osteomyelitis further complicated the management of endocarditis. The dilemma was successfully managed by surgical removal of the ICD device and combination antimicrobial therapy with high-dose daptomycin and fosfomycin. Conclusions Surgical removal of intracardiac devices remains an important adjunctive measure in the treatment of endocarditis. Our case suggests that combination therapy is more favorable than single-agent therapy for infections caused by DNS S. aureus.

  14. MORPHOLOGICAL ALTERATIONS OF STAPHYLOCOCCUS AUREUS CAUSED BY ARYL ALIPHATIC AMINOALCOHOL DERIVATIVE

    Directory of Open Access Journals (Sweden)

    Dronova M.

    2015-05-01

    Full Text Available Increasing of antimicrobial resistance has created a critical need of the novel antimicrobial agents. One of the promising chemical classes for its development are aryl aliphatic aminoalcohols. New compounds of this class were synthesized at the Institute of organic chemistry (Kiev, Ukraine, by Y. Korotkiy. After the screening studies compound KVM-194 was selected as the potent antistaphylococcal agent. The aim of the study was to examine ultrastructural changes in the bacterial cells under the influence of the compound KVM-194. Materials and methods. Staphylococcus aureus ATCC 25923 was used in all experiments. The minimum inhibitory concentration was determined by serial macrodilution method in Mueller-Hinton broth. Bacteria were exposed to the 0,5 MIC and 5 MICs of the KVM- 194 for 1 h and 24 h. Ultrastructure of intact and treated Staphylococcus aureus cells was examined by transmission electron microscopy after contrasting by osmium tetraoxide and lead citrate. Results and Discussion. The compound KVM-194 possesses a distinct antibacterial activity against Staphylococcus aureus, the minimum inhibitory concentration is 1.25 μg/ml. We found that exposure to KVM-194 at a subinhibitory concentration resulted in alterations of the cell morphology even after 1 h of treatment. The roughness of the cell surface and emerging of the intracellular particles of different electron density were observed. Increase of the incubation time to 24 h led to detachment of membrane from cytoplasm, multimembrane structures within cells emergence and formation of nonpolar septum. 1 h exposition to suprainhibitory concentration of KVM-194 resulted in nucleoid fragmentation, septum abnormalities and necrosis of some cells. We found that increasing of the incubation period to 24 h led to exacerbation of alterations: cell wall rupture, leakage of cytoplasm and a large number of lysed cells were registered. Conclusion. Observed alterations, suggest the possible

  15. Spontaneous Bacterial Pericarditis and Coronary Sinus Endocarditis Caused by Oxacillin-Susceptible Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Maurício N. Machado

    2010-01-01

    Full Text Available This paper describes a case of a 44-year-old male patient previously healthy admitted with an unusual spontaneous acute bacterial pericarditis associated with coronary sinus mass. Two-dimensional echocardiography showed large loculated pericardial effusion with signs of diastolic restriction and an image suggesting vegetation in topography of the right atrium coronary sinus. Pericardial drainage, coronary sinus vegetation resection, and antibiotic therapy with Oxacillin were performed due to Oxacillin-susceptible Staphylococcus aureus identified on the pericardial effusion and blood culture. This is a rare condition and a unique combination of a spontaneous acute bacterial pericarditis with coronary sinus endocarditis without cardiac valve compromise.

  16. Colonic Perforation Caused by Methicillin-Resistant Staphylococcus aureus Enteritis After Total Gastrectomy: A Case Report.

    Science.gov (United States)

    Furukawa, Kenei; Tsutsumi, Jun; Takayama, Sumio; Mashiko, Hiroshi; Shiba, Hiroaki; Yanaga, Katsuhiko

    2015-03-01

    A 68-year-old man underwent total gastrectomy and splenectomy for adenocarcinoma and low anterior resection for carcinoma in tubulo-villous adenoma of the rectum. Broad-spectrum antibiotics were administered for postoperative pancreatic fistula. Methicillin-resistant Staphylococcus aureus enteritis occurred on the 50th postoperative day and cecal perforation followed. The patient underwent construction of cecostomy with peritoneal drainage, and vancomycin was administered orally and per cecostomy for 2 weeks. The patient recovered well and was discharged at 35 days after re-operation in good general condition.

  17. Invasive Community-Acquired Methicillin-Resistant Staphylococcus aureus in a Japanese Girl with Disseminating Multiple Organ Infection: A Case Report and Review of Japanese Pediatric Cases

    Directory of Open Access Journals (Sweden)

    Ryuta Yonezawa

    2015-01-01

    Full Text Available Pediatric invasive community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA infection is very serious and occasionally fatal. This infectious disease is still a relatively rare and unfamiliar infectious disease in Japan. We report a positive outcome in a 23-month-old Japanese girl with meningitis, osteomyelitis, fasciitis, necrotizing pneumonia, urinary tract infection, and bacteremia due to CA-MRSA treated with linezolid. PCR testing of the CA-MRSA strain was positive for PVL and staphylococcal enterotoxin b and negative for ACME. SCC mec was type IVa. This case underscores the selection of effective combinations of antimicrobial agents for its treatment. We need to be aware of invasive CA-MRSA infection, which rapidly progresses with a serious clinical course, because the incidence of the disease may be increasing in Japan.

  18. Catalase-negative, methicillin-resistant Staphylococcus aureus as a cause of septicemia Staphylococcus aureus catalase-negativo resistente a meticilina como causa de septicemia

    Directory of Open Access Journals (Sweden)

    Ana Lúcia Innaco de Carvalho

    2003-01-01

    Full Text Available A catalase-negative methicillin-resistant Staphylococcus aureus (MRSA was isolated from blood, venous catheter spike and bone marrow collected from an HIV-positive man with lobar pneumonia and sepsis after ten days of hospitalization. The isolate was resistant to oxacillin (positive for penicillin-binding protein 2', ceftriaxone, clindamycin and clarithromycin, and susceptible to vancomycin. This is the first case of septicemia due to a catalase-negative S. aureus reported in Brazil, and, to our knowledge, it is the first case of catalase-negative MRSA reported in the literature. We believe that the patient acquired the S. aureus infection within the hospital environment since it was isolated ten days after hospitalization, it was isolated in a venous catheter spike, and the antibiotic resistance profile is similar to other S. aureus isolates recovered from infections in our hospital.Em um paciente HIV-positivo, com pneumonia lobar e septicemia, foi isolada, após dez dias de internação, uma cepa de Staphylococcus aureus catalase-negativa, resistente a meticilina/oxacilina (MRSA, de culturas de sangue, cateter venoso central e medula óssea. A cepa era resistente a oxacilina (PBP 2' positivo, ceftriaxona, clindamicina e claritromicina, e sensível a vancomicina. Este é o primeiro caso, reportado no Brasil, de uma septicemia por S. aureus catalase-negativo e, em nosso conhecimento, o primeiro caso de um S. aureus catalase-negativo resistente a meticilina. Nós acreditamos que o paciente tenha adquirido a infecção no ambiente hospitalar, uma vez que esta cepa foi isolada aos dez dias de internação, foi isolada em cateter venoso central e o perfil de sensibilidade aos antimicrobianos é semelhante ao dos S. aureus de infecções nosocomiais que ocorrem em nosso hospital.

  19. Biotic Homogenization Caused by the Invasion of Solidago canadensis in China

    Institute of Scientific and Technical Information of China (English)

    CHEN Guo-qi; ZHANG Chao-bin; MA Ling; QIANG Sheng; John A Silander; Li Li Qi

    2013-01-01

    Although studies argue that invasive species can cause biotic differentiation, some cases show that biological invasions actually decrease biodiversity through biotic homogenization. The concept of biotic homogenization through the invasion of a certain serious invasive plant species merit more studies. Hence, we used field surveys to quantitatively compare invasive populations of Solidago canadensis (SC) in China with the control sites (adjacent sites to SC present sites yet without the species) and SC native populations in the USA. We found that plant communities in SC invaded habitats shared similarities with those in SC native ranges. Bray-Curtis similarity clearly showed that the composition of plant communities in SC invaded habitats were similar to those in SC native ranges. Both in the native and introduced range, plant communities with SC present were characterized by SC being dominant, significantly lower species richness,α-diversity andβ-diversity, as well as a decrease in the correlation coefficient between geographic distance and floristic similarities. SC favors fertile and moist loam habitat, while it dominated in various habitats in China, where more than 20 different dominants should have occurred. In conclusion, serious invasive species can quickly remodel and homogenize diverse communities by dominating them.

  20. [Infections caused by multi-resistant Gram-positive bacteria (Staphylococcus aureus and Enterococcus spp.)].

    Science.gov (United States)

    Cantón, Rafael; Ruiz-Garbajosa, Patricia

    2013-10-01

    Methicillin -resistant Staphylocccus aureus (MRSA) and multirresistant entorococci are still problematic in nosocomial infections and new challenges have emerged for their containment. MRSA has increased the multiresistant profile; it has been described vancomycin and linezolid resistant isolates and isolates with decreased daptomycin susceptibility. Moreover, new clones (ST398) have emerged, initially associated with piggeries, and new mec variants (mecC) with livestock origin that escape to the detection with current molecular methods based on mecA gene have been detected. In enterococci, linzeolid resistant isolates and isolates with deceased susceptibility to daptomycin have been described. Moreover, ampicillin resistant Enterococcus faecium due to β-lactamase production has been recently found in Europe. Control of MRSA isolates and multiresistant enteroccocci should combined antibiotic stewardship strategies and epidemiological measures, including detection of colonized patients in order to reduce colonization pressure and their transmission.

  1. Foliar Nutritional Quality Explains Patchy Browsing Damage Caused by an Invasive Mammal.

    Directory of Open Access Journals (Sweden)

    Hannah R Windley

    Full Text Available Introduced herbivores frequently inflict significant, yet patchy damage on native ecosystems through selective browsing. However, there are few instances where the underlying cause of this patchy damage has been revealed. We aimed to determine if the nutritional quality of foliage could predict the browsing preferences of an invasive mammalian herbivore, the common brushtail possum (Trichosurus vulpecula, in a temperate forest in New Zealand. We quantified the spatial and temporal variation in four key aspects of the foliar chemistry (total nitrogen, available nitrogen, in vitro dry matter digestibility and tannin effect of 275 trees representing five native tree species. Simultaneously, we assessed the severity of browsing damage caused by possums on those trees in order to relate selective browsing to foliar nutritional quality. We found significant spatial and temporal variation in nutritional quality among individuals of each tree species examined, as well as among tree species. There was a positive relationship between the available nitrogen concentration of foliage (a measure of in vitro digestible protein and the severity of damage caused by browsing by possums. This study highlights the importance of nutritional quality, specifically, the foliar available nitrogen concentration of individual trees, in predicting the impact of an invasive mammal. Revealing the underlying cause of patchy browsing by an invasive mammal provides new insights for conservation of native forests and targeted control of invasive herbivores in forest ecosystems.

  2. HUMAN INVASIVE DERMATOPHYTIC DISEASE IS CAUSED BY INBORN ERRORS OF CARD9

    OpenAIRE

    Lanternier, F.; Pathan, S.; Vincent, Q.; L. Liu; Cypowij, S.; Prando, C; Migaud, M.; TAIBI, L.; Ammar-Khodja, A.; Stambouli, O.; Boudghene; Guellil, B.; Jacobs, F.; Goffard, J.C; Shepers, K.

    2012-01-01

    Dermatophytic disease is an invasive, sometimes life-threatening, fungal infection caused by dermatophytes, in which there is extensive cutaneous and subcutaneous tissue involvement, frequent dissemination to the lymph nodes and occasionally to the central nervous system. This condition, which is different from banal superficial dermatophyte infection (dermatophytosis), has mostly been reported in North African consanguineous multiplex families, strongly suggesting a Mendelian genetic etiolog...

  3. Successful treatment of an invasive fungal infection caused by Talaromyces sp. with voriconazole

    Directory of Open Access Journals (Sweden)

    Uluhan Sili

    2015-06-01

    Full Text Available Invasive fungal infections (IFI are on the rise due to increasing numbers of immunosuppressed and critically ill patients. A malignant-looking pulmonary nodule in an immunosuppressed patient may indeed be caused by a fungal organism. We report a patient, who was eventually diagnosed with an IFI caused by an agent of hyalohyphomycosis, Talaromyces sp. determined via molecular methods and succesfully treated with voriconazole.

  4. Increased cytotoxicity and streptolysin O activity in group G streptococcal strains causing invasive tissue infections

    DEFF Research Database (Denmark)

    Siemens, Nikolai; Kittang, Bård R; Chakrakodi, Bhavya;

    2015-01-01

    Streptococcus dysgalactiae subsp. equisimilis (SDSE) has emerged as an important cause of severe skin and soft tissue infections, but little is known of the pathogenic mechanisms underlying tissue pathology. Patient samples and a collection of invasive and non-invasive group G SDSE strains (n = 69......) were analyzed with respect to virulence factor expression and cytotoxic or inflammatory effects on human cells and 3D skin tissue models. SDSE strains efficiently infected the 3D-skin model and severe tissue pathology, inflammatory responses and altered production of host structural framework proteins...

  5. Staphylococcus aureus vaccines: Deviating from the carol.

    Science.gov (United States)

    Missiakas, Dominique; Schneewind, Olaf

    2016-08-22

    Staphylococcus aureus, a commensal of the human nasopharynx and skin, also causes invasive disease, most frequently skin and soft tissue infections. Invasive disease caused by drug-resistant strains, designated MRSA (methicillin-resistant S. aureus), is associated with failure of antibiotic therapy and elevated mortality. Here we review polysaccharide-conjugate and subunit vaccines that were designed to prevent S. aureus infection in patients at risk of bacteremia or surgical wound infection but failed to reach their clinical endpoints. We also discuss vaccines with ongoing trials for combinations of polysaccharide-conjugates and subunits. S. aureus colonization and invasive disease are not associated with the development of protective immune responses, which is attributable to a large spectrum of immune evasion factors. Two evasive strategies, assembly of protective fibrin shields via coagulases and protein A-mediated B cell superantigen activity, are discussed as possible vaccine targets. Although correlates for protective immunity are not yet known, opsonophagocytic killing of staphylococci by phagocytic cells offers opportunities to establish such criteria. PMID:27526714

  6. Comparison of antimicrobial agents as therapy for experimental endocarditis: caused by methicillin-resistant Staphylococcus aureus.

    Science.gov (United States)

    Sacar, Mustafa; Sacar, Suzan; Cevahir, Nural; Onem, Gokhan; Teke, Zafer; Asan, Ali; Turgut, Huseyin; Adali, Fahri; Kaleli, Ilknur; Susam, Ibrahim; Yaylali, Yalin Tolga; Baltalarli, Ahmet

    2010-01-01

    We used an experimental rat model to compare the therapeutic efficacy of teicoplanin, linezolid, and quinupristin/dalfopristin with that of vancomycin as standard therapy for infective endocarditis.Aortic endocarditis was induced in rats by insertion of a polyethylene catheter into the left ventricle, followed by intravenous inoculation of 106 colony-forming units of methicillin-resistant Staphylococcus aureus 24 hours later. Forty-eight hours after bacterial challenge, intravenous antibiotic therapies were initiated. There were 6 groups of 8 rats each: uninfected control; infected, untreated control; vancomycin-treated (40 mg/kg twice daily); teicoplanin-treated (20 mg/kg twice daily after a loading dose of 40 mg/kg); linezolid-treated (75 mg/kg 3 times daily for 1 day, then 75 mg/kg twice daily); and quinupristin/dalfopristin-treated (30 mg/kg twice daily and an additional 10 mg/kg dalfopristin infusion over 6 to 12 hr daily). At the end of therapy, the aortic valve vegetations in the drug-treated rats were evaluated microbiologically.Compared with the infected, untreated group, all drug-treated groups had significantly reduced bacterial titers in the vegetations. Vancomycin, teicoplanin, and quinupristin/dalfopristin all effectively reduced the quantitative bacterial cultures of aortic valve vegetations. In addition, there was no significant difference in the comparative efficacy of teicoplanin, linezolid, and quinupristin/dalfopristin. Vancomycin significantly reduced bacterial counts in comparison with linezolid, which was nonetheless also effective.Our experimental model showed that each of the investigated antimicrobial agents was effective in the treatment of infective endocarditis. PMID:20844611

  7. Difference in virulence between Staphylococcus aureus isolates causing gangrenous mastitis versus subclinical mastitis in a dairy sheep flock.

    OpenAIRE

    Vautor, Eric; Cockfield, Joshua; Le Maréchal, Caroline; Le Loir, Yves; Chevalier, Marlène; Robinson, D. Ashley; Thiery, Richard; Lindsay, Jodi

    2009-01-01

    Staphylococcus aureus mastitis in dairy sheep ranges from subclinical mastitis to lethal gangrenous mastitis. Neither the S. aureus virulence factors nor the host-factors or the epidemiological events contributing to the different outcomes are known. In a field study in a dairy sheep farm over 21 months, 16 natural isolates of S. aureus were collected from six subclinical mastitis cases, one lethal gangrenous mastitis case, nasal carriage from eight ewes and one isolate from ambient air in th...

  8. Efficacy of Targeted 5-day Combined Parenteral and Intramammary Treatment of Clinical Mastitis Caused by Penicillin-Susceptible or Penicillin-Resistant Staphylococcus aureus

    Science.gov (United States)

    Taponen, S; Jantunen, A; Pyörälä, E; Pyörälä, S

    2003-01-01

    Combined parenteral and intramammary treatment of mastitis caused by Staphylococcus aureus was compared to parenteral treatment only. Cows with clinical mastitis (166 mastitic quarters) caused by S. aureus treated by veterinarians of the Ambulatory Clinic of the Faculty of Veterinary Medicine during routine farm calls were included. Treatment was based on in vitro susceptibility testing of the bacterial isolate. Procaine penicillin G (86 cases due to β-lactamase negative strains) or amoxycillin-clavulanic acid (24 cases due to β-lactamase positive strains) was administered parenterally and intramammarily for 5 days. Efficacy of treatments was assessed 2 and 4 weeks later by physical examination, bacteriological culture, determination of CMT, somatic cell count and NAGase activity in milk. Quarters with growth of S. aureus in at least one post-treatment sample were classified as non-cured. As controls we used 41 clinical mastitis cases caused by penicillin-susceptible S. aureus isolates treated with procaine penicillin G parenterally for 5 days and 15 cases due to penicillin-resistant isolates treated with spiramycin parenterally for 5 days from the same practice area. Bacteriological cure rate after the combination treatment was 75.6% for quarters infected with penicillin-susceptible S. aureus isolates, and 29.2% for quarters infected with penicillin-resistant isolates. Cure rate for quarters treated only parenterally with procaine penicillin G was 56.1% and that for quarters treated with spiramycin 33.3%. The difference in cure rates between mastitis due to penicillin-susceptible and penicillin-resistant S. aureus was highly significant. Combined treatment was superior over systemic treatment only in the β-lactamase negative group. PMID:14650544

  9. Nosocomial bloodstream infection in patients caused by Staphylococcus aureus: drug susceptibility, outcome, and risk factors for hospital mortality

    Institute of Scientific and Technical Information of China (English)

    CHEN Rong; YAN Zhong-qiang; FENG Dan; LUO Yan-ping; WANG Lei-li; SHEN Ding-xia

    2012-01-01

    Background Previous studies have different viewpoints about the clinical impact of methicillin resistance on mortality of hospital-acquired bloodstream infection (BSI) patients with Staphylococcus aureus (S.aureus).The objective of this study was to investigate the mortality of hospital-acquired BSI with S.aureus in a military hospital and analyze the risk factors for the hospital mortality.Methods A retrospective cohort study was performed in patients admitted to the biggest military tertiary teaching hospital in China between January 2006 and May 2011.All included patients had clinically significant nosocomial BSI with S.aureus.Multivariate Logistic regression analysis was used to identify the risk factors for hospital mortality of patients with S.aureus BSI.Results One hundred and eighteen patients of more than one year old were identified as clinically and microbiologically confirmed nosocomial bacteraemia due to S.aureus,and 75 out of 118 patients were infected with methicillin-resistant S.aureus (MRSA).The overall mortality of nosocomial S.aureus BSI was 28.0%.Methicillin resistance in S.aureus bacteremia was associated with significant increase in the length of hospitalization and high proportion of inappropriate empirical antibiotic treatment.After Logistic regression analysis,the severity of clinical manifestations (APACHE Ⅱ score) (odds ratio (OR) 1.22,95% confidence interval (CI) 1.12-1.34) and inadequacy of empirical antimicrobial therapy (OR 0.25,95% CI 0.09-0.69) remained as risk factors for hospital mortality.Conclusions Nosocomial S.aureus BSI was associated with high in-hospital mortality.Methicillin resistance in S.aureus has no significant impact on the outcome of patients with staphylococcal bacteremia.Proper empirical antimicrobial therapy is very important to the prognosis.

  10. Cost Comparison of Linezolid Versus Vancomycin for Treatment of Complicated Skin and Skin-Structure Infection Caused by Methicillin-Resistant Staphylococcus aureus in Quebec

    Directory of Open Access Journals (Sweden)

    Martine Pettigrew

    2012-01-01

    Full Text Available BACKGROUND: In Canada, complicated skin and skin-structure infection (cSSSI caused by methicillin-resistant Staphylococcus aureus (MRSA is usually treated with antibiotics in hospital, with a follow-up course at home for stable patients. The cost implications of using intravenous and oral linezolid instead of intravenous vancomycin in Canadian clinical practice have not been examined.

  11. Increasing Prevalence of Methicillin-Resistant Staphylococcus aureus Causing Nosocomial Infections at a University Hospital in Taiwan from 1986 to 2001

    OpenAIRE

    Hsueh, Po-Ren; Teng, Lee-Jene; Chen, Wen-Hwei; Pan, Huei-Ju; Chen, Mei-Lin; Chang, Shan-Chwen; Luh, Kwen-Tay; Lin, Fang-Yue

    2004-01-01

    A rapid emergence of nosocomial methicillin-resistant Staphylococcus aureus (MRSA) infection (from 26.3% in 1986 to 77% in 2001) was found. The susceptibility of 200 nonduplicate blood isolates of MRSA and 100 MRSA isolates causing refractory bacteremia to 22 antimicrobial agents disclosed that glycopeptides, quinupristin-dalfopristin, and linezolid remained the most active agents.

  12. A new lipase as a pharmaceutical target for battling infections caused by Staphylococcus aureus: Gene cloning and biochemical characterization.

    Science.gov (United States)

    Ünlü, Aişe; Tanriseven, Aziz; Sezen, I Yavuz; Çelik, Ayhan

    2015-01-01

    Staphylococcus aureus lipases along with other cell-wall-associated proteins and enzymes (i.e., catalase, coagulase, protease, hyaluronidase, and β-lactamase) play important roles in the pathogenesis of S. aureus and are important subject of drug targeting. The appearance of antibiotic-resistant types of pathogenic S. aureus (e.g., methicillin-resistant S. aureus, MRSA) is a worldwide medical problem. In the present work, a novel lipase from a newly isolated MRSA strain from a cow with subclinical mastitis was cloned and biochemically characterized. The mature part of the lipase was expressed in Escherichia coli and purified by nickel affinity chromatography. It displays a high lipase activity at pH 8.0 and 25 °C using p-nitrophenyl palmitate and has a preference for medium-long-chain substrates of p-nitrophenyl esters (pNPC10-C16). Furthermore, in search of inhibitors, the effect of farnesol on the growth of S. aureus and the lipase activity was also studied. Farnesol inhibits the growth of S. aureus and is a mixed-type inhibitor with Ki and Ki (') values of 0.2 and 1.2 mmol L(-1), respectively. A lipase with known properties could not only serve as a template for developing inhibitors for S. aureus but also a valuable addition to enzyme toolbox of biocatalysis. The discovery of this lipase can be potentially important and could provide a new target for pharmaceutical intervention against S. aureus infection. PMID:25385356

  13. Invasion of non-native grasses causes a drop in soil carbon storage in California grasslands

    Energy Technology Data Exchange (ETDEWEB)

    Koteen, Laura E; Harte, John [Energy and Resources Group, 310 Barrows Hall, University of California, Berkeley, CA 94720 (United States); Baldocchi, Dennis D, E-mail: lkoteen@berkeley.edu [Department of Environmental Science, Policy and Management, 137 Mulford Hall, University of California, Berkeley, CA 94720 (United States)

    2011-10-15

    Vegetation change can affect the magnitude and direction of global climate change via its effect on carbon cycling among plants, the soil and the atmosphere. The invasion of non-native plants is a major cause of land cover change, of biodiversity loss, and of other changes in ecosystem structure and function. In California, annual grasses from Mediterranean Europe have nearly displaced native perennial grasses across the coastal hillsides and terraces of the state. Our study examines the impact of this invasion on carbon cycling and storage at two sites in northern coastal California. The results suggest that annual grass invasion has caused an average drop in soil carbon storage of 40 Mg/ha in the top half meter of soil, although additional mechanisms may also contribute to soil carbon losses. We attribute the reduction in soil carbon storage to low rates of net primary production in non-native annuals relative to perennial grasses, a shift in rooting depth and water use to primarily shallow sources, and soil respiratory losses in non-native grass soils that exceed production rates. These results indicate that even seemingly subtle land cover changes can significantly impact ecosystem functions in general, and carbon storage in particular.

  14. Host growth can cause invasive spread of crops by soilborne pathogens.

    Directory of Open Access Journals (Sweden)

    Melen Leclerc

    Full Text Available Invasive soilborne plant pathogens cause substantial damage to crops and natural populations, but our understanding of how to prevent their epidemics or reduce their damage is limited. A key and experimentally-tested concept in the epidemiology of soilborne plant diseases is that of a threshold spacing between hosts below which epidemics (invasive spread can occur. We extend this paradigm by examining how plant-root growth may alter the conditions for occurrence of soilborne pathogen epidemics in plant populations. We hypothesise that host-root growth can 1 increase the probability of pathogen transmission between neighbouring plants and, consequently, 2 decrease the threshold spacing for epidemics to occur. We predict that, in systems initially below their threshold conditions, root growth can trigger soilborne pathogen epidemics through a switch from non-invasive to invasive behaviour, while in systems above threshold conditions root growth can enhance epidemic development. As an example pathosystem, we studied the fungus Rhizoctonia solani on sugar beet in field experiments. To address hypothesis 1, we recorded infections within inoculum-donor and host-recipient pairs of plants with differing spacing. We translated these observations into the individual-level concept of pathozone, a host-centred form of dispersal kernel. To test hypothesis 2 and our prediction, we used the pathozone to parameterise a stochastic model of pathogen spread in a host population, contrasting scenarios of spread with and without host growth. Our results support our hypotheses and prediction. We suggest that practitioners of agriculture and arboriculture account for root system expansion in order to reduce the risk of soilborne-disease epidemics. We discuss changes in crop design, including increasing plant spacing and using crop mixtures, for boosting crop resilience to invasion and damage by soilborne pathogens. We speculate that the disease-induced root growth

  15. Epidemiology and outcome of pneumonia caused by methicillin-resistant Staphylococcus aureus (MRSA in Canadian hospitals.

    Directory of Open Access Journals (Sweden)

    Manal Tadros

    Full Text Available BACKGROUND: MRSA remains a leading cause of hospital-acquired (HAP and healthcare-associated pneumonia (HCAP. We describe the epidemiology and outcome of MRSA pneumonia in Canadian hospitals, and identify factors contributing to mortality. METHODS: Prospective surveillance for MRSA pneumonia in adults was done for one year (2011 in 11 Canadian hospitals. Standard criteria for MRSA HAP, HCAP, ventilator-associated pneumonia (VAP, and community-acquired pneumonia (CAP were used to identify cases. MRSA isolates underwent antimicrobial susceptibility testing, and were characterized by pulsed-field gel electrophoresis (PFGE and Panton-Valentine leukocidin (PVL gene detection. The primary outcome was all-cause mortality at 30 days. A multivariable analysis was done to examine the association between various host and microbial factors and mortality. RESULTS: A total of 161 patients with MRSA pneumonia were identified: 90 (56% with HAP, 26 (16% HCAP, and 45 (28% CAP; 23 (14% patients had VAP. The mean (± SD incidence of MRSA HAP was 0.32 (± 0.26 per 10,000 patient-days, and of MRSA VAP was 0.30 (± 0.5 per 1,000 ventilator-days. The 30-day all-cause mortality was 28.0%. In multivariable analysis, variables associated with mortality were the presence of multiorgan failure (OR 8.1; 95% CI 2.5-26.0, and infection with an isolate with reduced susceptibility to vancomycin (OR 2.5, 95% CI 1.0-6.3. CONCLUSIONS: MRSA pneumonia is associated with significant mortality. Severity of disease at presentation, and infection caused by an isolate with elevated MIC to vancomcyin are associated with increased mortality. Additional studies are required to better understand the impact of host and microbial variables on outcome.

  16. The Novel Transcriptional Regulator SA1804 Is Involved in Mediating the Invasion and Cytotoxicity of Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    JUNSHU eYANG

    2015-03-01

    Full Text Available The two-component regulatory system, SaeRS, controls expression of important virulence factors, including toxins and invasins, which contribute to the pathogenicity of Staphylococcus aureus. Previously, we conducted a transcriptomics study for identification of SaeRS regulon and found that inactivation of SaeRS dramatically enhances the transcription of a novel transcriptional regulator (SA1804. This led us to question whether SA1804 is involved in bacterial pathogenicity by regulating the expression of virulence factors. To address this question, we created sa1804, saeRS, and sa1804/saeRS double deletion mutants in a USA300 community-acquired MRSA strain, 923, and determined their impact on the pathogenicity. The deletion of sa1804 dramatically increased the cytotoxicity and enhanced the capacity of bacteria to invade into the epithelial cells (A549, whereas the deletion of saeRS eliminated the cytotoxicity and abolished the bacterial ability to invade into the epithelial cells. Moreover, the double deletions of sa1804 and saeRS appeared a similar phenotype with the saeRS null mutation. Furthermore, we determined the regulatory mechanism of SA1804 using qPCR and gel-shift approaches. Our data indicate that the novel virulence repressor SA1804 is dependent on the regulation of SaeRS. This study sheds light on the regulatory mechanism of virulence factors and allows for us further elucidate the molecular pathogenesis of S. aureus.

  17. The Increasing Problem of Wound Bacterial Burden and Infection in Acute and Chronic Soft-Tissue Wounds Caused by Methicillin-Resistant Staphylococcus aureus

    OpenAIRE

    Demling, Robert H.; Waterhouse, Barbara

    2007-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) has become a leading cause of colonization and infection in both acute and chronic soft-tissue wounds. Objective: Our objective is to define this current epidemic problem caused by both community-acquired MRSA (CA-MRSA) and hospital-acquired MRSA (HA-MRSA), focusing on the similarities and differences between these 2 isolates as well as the impact on wound management decisions. Methods: Methods used include a literature review on the growth o...

  18. Staphylococcus aureus toxins.

    Science.gov (United States)

    Otto, Michael

    2014-02-01

    Staphylococcus aureus is a dangerous pathogen that causes a variety of severe diseases. The virulence of S. aureus is defined by a large repertoire of virulence factors, among which secreted toxins play a preeminent role. Many S. aureus toxins damage biological membranes, leading to cell death. In particular, S. aureus produces potent hemolysins and leukotoxins. Among the latter, some were recently identified to lyse neutrophils after ingestion, representing an especially powerful weapon against bacterial elimination by innate host defense. Furthermore, S. aureus secretes many factors that inhibit the complement cascade or prevent recognition by host defenses. Several further toxins add to this multi-faceted program of S. aureus to evade elimination in the host. This review will give an overview over S. aureus toxins focusing on recent advances in our understanding of how leukotoxins work in receptor-mediated or receptor-independent fashions.

  19. Infectious caused by community-acquired Methicillin-Resistant Staphylococcus aureus (CA-MRSA: three-years experience of an universitary hospital in Rome

    Directory of Open Access Journals (Sweden)

    Anna Altieri

    2010-06-01

    Full Text Available To date methicillin-resistant Staphylococcus aureus (MRSA is one of the most common pathogens causing nosocomial infections(1. In Europe the proportion of MRSA is increasing sharply and the distribution varies from country to country. In recent years there has, in various parts of the world, the emergence of infection with strains of S. aureus methicillin-resistant community-acquired (CA-MRSA than those circulating in hospitals(2. These strains contain a gene that confers resistance to methicillin (mec A SSC mec IV which is usually associated with the gene for Leukocidin Panton Valentine (PVL toxin responsible for necrosis of skin and soft tissue (3. In 2006-2008, at the Laboratory of Bacteriology PolyclinicTor Vergata,were isolated a total of 738 strains of S. aureus from biological samples of different nature (oral, vaginal secretions, wound swab, secreted headset, etc ... of patients related to our surgeries.The identification and study of drug sensitivity of strains were performed with the automatic VITEK2 (bioMérieux. Of the 738 strains of S. aureus identified 212 (28.7% were resistant to methicillin (MRSA, with an increasing trend over the years: 46 isolates, respectively, in 2006, 76 in 2007 and 90 in 2008. The highest frequency of MRSA (varying between 85% and 95% was detected in wound swabs from the dispensary and diabetes (diabetic foot.

  20. 金黄色葡萄球菌致肺部感染的耐药谱分析%Drug resistant spectrum of staphylococcus aureus causing pulmonary infection

    Institute of Scientific and Technical Information of China (English)

    王良兴; 杨乐和; 余方友; 刘莹; 李挺建; 姚丹; 徐永健

    2011-01-01

    OBJECTIVE To investigate the clinical characteristics and resistance of Staphylococcus aureus lung infections so as to guide the treatment of S. aureus lung infections. METHODS Clinical materials of S. aureus causing lung infections and sputum culture specimen were collected and the sensitivity of isolated strains to antibacterial agents. RESULTS Among 100 cases of S. aureus causing lung infections, 70. 0% were the elderly patients. One hundred strains of S. aureus were isolated, including 85 metieillin-resistant S. aureus(MRSA) and 15 meticillin-sensitive S. aureus (MSSA). S. aureus showed multi-drug resistance to many kinds of antibiotics,while all isolates of S. aureus were sensitive to vancomycin, linezolid, teicoplanin, quinupristin/dalfopristin and furadantin. And besides, only the resistant rate to compound sulfamethoxazole was lower than 20. 0%. The resistant rates of MRSA to erythromycin, clindamycin hydrochloride, rifampicin, gentamicin, tetracycline and levofloxacin were all significantly higher than those of MSSA(P<0.01). CONCLUSION S. aureus causing lung infections usually occur in the elderly patients. MRSA shows multi-resistant characteristics except for vancomycin, linezolid, teieoplanin, quinupristin/dalfopristin and furadantin with high sensitivity.%目的 调查引起肺部感染金黄色葡萄球菌的耐药谱.方法 收集确诊为金黄色葡萄球菌肺部感染病例的痰培养标本及临床资料,进行药敏试验.结果 100例由金黄色葡萄球菌引起的肺部感染患者中,70.0%为老年患者;85株为耐甲氧西林金黄色葡萄球菌(MRSA);金黄色葡萄球菌对多种抗菌药物呈普遍耐药,但所有分离株对万古霉素、利奈唑胺、替考拉宁、喹奴普汀/达福普汀及呋喃妥因均敏感,此外耐药率<20.0%的抗菌药物仅1种,匀磺胺甲噁唑/甲氧苄啶;MRSA对红霉素、克林霉素等药物的耐药率显著高于MSSA(P<0.01).结论 金黄色葡萄球菌引起的肺部感染易发

  1. Latent class analysis of the diagnostic characteristics of PCR and conventional bacteriological culture in diagnosing intramammary infections caused by Staphylococcus aureus in dairy cows at dry off

    DEFF Research Database (Denmark)

    Cederlöf, Sara Ellinor; Toft, Nils; Aalbæk, Bent;

    2012-01-01

    ABSTRACT: BACKGROUND: Staphylococcus aureus is one of the most common causes of intramammary infections in dairy cows at dry off. Reliable identification is important for disease management on herd level and for antimicrobial treatment of infected animals. Our objective was to evaluate the test...... characteristics of PathoProof TM Mastitis PCR Assay and bacteriological culture (BC) in diagnosing bovine intramammary infections caused by S. aureus at dry off at different PCR cycle threshold (Ct)-value cut-offs. METHODS: Sterile quarter samples and non-sterile composite samples from 140 animals in seven herds...... were collected in connection with the dairy herd improvement (DHI) milk recording. All quarter samples were analyzed using BC whereas all composite samples were analyzed with PathoProof TM Mastitis PCR Assay. Latent class analysis was used to estimate test properties for PCR and BC in the absence...

  2. Cost comparison of linezolid versus vancomycin for treatment of complicated skin and skin-structure infection caused by methicillin-resistant Staphylococcus aureus in Quebec

    OpenAIRE

    Martine Pettigrew; Daniel JG Thirion; Michael Libman; Giovanni Zanotti

    2012-01-01

    BACKGROUND: In Canada, complicated skin and skin-structure infection (cSSSI) caused by methicillin-resistant Staphylococcus aureus (MRSA) is usually treated with antibiotics in hospital, with a follow-up course at home for stable patients. The cost implications of using intravenous and oral linezolid instead of intravenous vancomycin in Canadian clinical practice have not been examined.OBJECTIVES: To evaluate the potential treatment cost impact for the Quebec health care system of linezolid v...

  3. Delta-toxin production deficiency in Staphylococcus aureus: a diagnostic marker of bone and joint infection chronicity linked with osteoblast invasion and biofilm formation.

    Science.gov (United States)

    Valour, F; Rasigade, J-P; Trouillet-Assant, S; Gagnaire, J; Bouaziz, A; Karsenty, J; Lacour, C; Bes, M; Lustig, S; Bénet, T; Chidiac, C; Etienne, J; Vandenesch, F; Ferry, T; Laurent, F

    2015-06-01

    Biofilm formation, intra-osteoblastic persistence, small-colony variants (SCVs) and the dysregulation of agr, the major virulence regulon, are possibly involved in staphylococcal bone and joint infection (BJI) pathogenesis. We aimed to investigate the contributions of these mechanisms among a collection of 95 Staphylococcus aureus clinical isolates from 64 acute (67.4%) and 31 chronic (32.6%) first episodes of BJI. The included isolates were compared for internalization rate, cell damage and SCV intracellular emergence using an ex vivo model of human osteoblast infection. Biofilm formation was assessed in a microbead immobilization assay (BioFilm Ring test). Virulence gene profiles were assessed by DNA microarray. Seventeen different clonal complexes were identified among the screened collection. The staphylococcal internalization rate in osteoblasts was significantly higher for chronic than acute BJI isolates, regardless of the genetic background. Conversely, no differences regarding cytotoxicity, SCV emergence, biofilm formation and virulence gene distribution were observed. Additionally, agr dysfunction, detected by the lack of delta-toxin production using whole-cell matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) analysis (n = 15; 15.8%), was significantly associated with BJI chronicity, osteoblast invasion and biofilm formation. These findings provide new insights into MSSA BJI pathogenesis, suggesting the correlation between chronicity and staphylococcal osteoblast invasion. This adaptive mechanism, along with biofilm formation, is associated with agr dysfunction, which can be routinely assessed by delta-toxin detection using MALDI-TOF spectrum analysis, possibly providing clinicians with a diagnostic marker of BJI chronicity at the time of diagnosis.

  4. Evolution of a fatal septic arthritis caused by a Panton-Valentine leukocidin (PVL)-producing Staphylococcus aureus strain.

    Science.gov (United States)

    Rafai, Mostafa; Abouelalaa, Khalil; Skhsoukh, Yassine; Balkhi, Hicham; Belyamani, Lahcen; Dimou, M'barek

    2013-10-01

    We report the observation of a septic arthritis of the knee complicated within first 36 hours by multiorgan failure including acute respiratory distress syndrome (ARDS), heart failure, acute renal failure and disseminated intravascular coagulation (DIC). A diagnosis of staphylococcal arthritis was suspected confirmed by direct examination, and culture showed a Staphylococcus aureus sensitive to methicillin. The sample sent to the National Reference Centre for Staphylococci (Lyon, France) for genetic analysis confirmed the isolate positive for the PVL gene expression. The fulminating evolution of a septic S. aureus arthritis in an otherwise healthy man should probably evoke the possibility of LPV strain. Anti-PLV antibiotics with anti-staphylococcal activity, such as clindamycin and linezolid should be started without waiting for typing of the S. aureus strain.

  5. Serotype distribution of Streptococcus pneumoniae causing invasive disease in the Republic of Ireland.

    LENUS (Irish Health Repository)

    Vickers, I

    2011-05-01

    The 7-valent pneumococcal conjugate vaccine (PCV7) was included in the routine infant immunization schedule in Ireland in September 2008. We determined the serotype of 977 S. pneumoniae isolates causing invasive disease between 2000-2002 and 2007-2008, assessed for the presence of the recently described serotype 6C and determined the susceptibility of isolates during 2007-2008 to penicillin and cefotaxime. Serotype 14 was the most common serotype during both periods and 7·7% of isolates previously typed as serotype 6A were serotype 6C. During 2000-2002 and 2007-2008, PCV7 could potentially have prevented 85% and 74% of invasive pneumococcal disease in the target population (i.e. children aged <2 years), respectively. The level of penicillin non-susceptibility was 17% in 2007-2008. Ongoing surveillance of serotypes is required to determine the impact of PCV7 in the Irish population and to assess the potential of new vaccines with expanded valency.

  6. The role of invasive ventilation in exacerbations of chronic obstructive pulmonary disease causing respiratory failure.

    Science.gov (United States)

    Kosky, Christopher; Turton, Charles

    2006-01-01

    Acute hypercapnic respiratory failure in chronic obstructive pulmonary disease can usually be managed initially with medical treatment and non- invasive ventilation. In circumstances where non- invasive ventilation cannot be used or has failed, intubation and invasive ventilation may be lifesaving. The outcome of patients with an exacerbation of COPD requiring invasive ventilation is better than often thought, with a hospital survival of 70-89%. Decisions regarding invasive ventilation made by physicians and patients with COPD are unpredictable and vary with the individual. This article reviews the role of invasive ventilation in exacerbations of COPD to assist decision making.

  7. Distinguishing Complicated from Uncomplicated Bacteremia Caused by Staphylococcus aureus: The Value of "New" and "Old" Serological Tests

    NARCIS (Netherlands)

    H.A. Verbrugh (Henri); W.H.F. Goessens (Wil); M.F. Michel; R. Peters (Roel)

    1986-01-01

    textabstractAntibody responses to staphylococcal α-toxin, cell wall teichoic acid, and cell wall peptodoglycan were measured in 259 serum samples from 74 consecutive patients with Staphylococcus aureus bacteremia. All patients with complicated bacteremia were seropositive in at least one of three te

  8. Molecular characterization of Staphylococcus aureus isolates causing skin and soft tissue infections in patients from Malakand, Pakistan.

    Science.gov (United States)

    Madzgalla, S; Syed, M A; Khan, M A; Rehman, S S; Müller, E; Reissig, A; Ehricht, R; Monecke, S

    2016-09-01

    Comparatively few studies have been published describing Staphylococcus aureus/MRSA epidemiology in Central Asia including Pakistan. Here, we report the genotyping of Staphylococcus aureus strains (that include both methicillin-susceptible and methicillin-resistant Staphylococcus aureus) from community- and hospital-acquired skin and soft-tissue infections in a tertiary care hospital in the Malakand district of the Khyber Pakhtunkhwa Province of Pakistan. Forty-five isolates of Staphylococcus aureus were characterized by microarray hybridization. Twenty isolates (44 %) were MRSA, whereas 22 (49 %) were PVL-positive. Fourteen isolates (31 %) harboured both mecA and PVL genes. The dominant clones were CC121-MSSA (n = 15, 33 %) and the PVL-positive "Bengal Bay Clone" (ST772-MRSA-V; n = 13, 29 %). The PVL-positive CC8-MRSA-IV strain "USA300" was found once. The pandemic ST239-MRSA-III strain was absent, although it has previously been observed in Pakistan. These observations require a re-assessment of schemes for initial antibiotic therapy to cover MRSA and they emphasise the need for a rapid and non-molecular test for PVL. PMID:27262852

  9. Molecular and bacteriological investigation of subclinical mastitis caused by Staphylococcus aureus and Streptococcus agalactiae in domestic bovids from Ismailia, Egypt.

    Science.gov (United States)

    Elhaig, Mahmoud Mohey; Selim, Abdelfattah

    2015-02-01

    A study was carried out to establish the prevalence of subclinical mastitis (SCM) in smallholder dairy farms in Ismailia, Egypt. A total of 340 milking cows and buffaloes were sampled from 60 farms, and 50 nasal swabs were collected from consenting farm workers. Milk samples were subjected to California mastitis test (CMT) and the positive samples were examined by bacterial culture and PCR to identify etiological agents. Based on CMT, the prevalence of SCM was 71.6 % in cattle and 43.5 % in buffaloes while the prevalence was 25.2 % at cow-quarter level and 21.7 % at buffaloes-quarter level. Bacteriological analysis showed that the most frequently identified bacteria were Staphylococcus (S.) aureus (38.3 %) and Streptococcus (Str.) agalactiae (20 %). The diagnostic sensitivity of PCR compared to bacterial culture was superior with S. aureus and Str. agalactiae detection being 41 and 22.6 %, respectively. Furthermore, methicillin-resistant S. aureus (MRSA) strains occurred in 52.2 and 45 % of isolates of animals and workers, respectively. Subclinical mastitis due to S. aureus and Str. agalactiae is endemic in smallholder dairy herds in Ismailia. The occurrence of MRSA in animals and workers highlights a need for wide epidemiological studies of MRSA and adopting control strategies. PMID:25374070

  10. Necrotizing Pneumonia Caused by Panton-Valentine Leucocidin-Producing Staphylococcus aureus Originating from a Bartholin's Abscess

    Directory of Open Access Journals (Sweden)

    N. Jung

    2008-01-01

    Full Text Available Background. Panton-Valentine leukocidin (PVL-producing Staphylococcus aureus is emerging as a serious problem worldwide. There has been an increase in the incidence of necrotizing lung infections in otherwise healthy young people with a very high mortality associated with these strains. Sporadic severe infectious complications after incision of Bartholin's abcesses have been described but involvement of S. aureus is rare. Case report. We present a 23-year-old apparently healthy female patient without any typical predisposing findings who developed severe sepsis with necrotizing pneumonia and multiple abscesses following incision of a Bartholin's abscess. Methicillin-sensitive S. aureus harbouring Panton-Valentine leucocidin genes were cultured from the abscess fluid, multiple blood cultures and a postoperative wound swab. Aggressive antibiotic therapy with flucloxacillin, rifampicin and clindamycin, drainage and intensive supportive care lead finally to recovery. Conclusions. S. aureus, in particular PVL-positive strains, should be considered when a young, immunocompetent person develops a fulminant necrotizing pneumonia. Minor infections—such as Bartholin's abscess—can precede this life-threating syndrome. Bactericidal antistaphylococcal antibiotics are recommended for treatment, and surgical procedures may become necessary.

  11. Livestock-associated methicillin-resistant Staphylococcus aureus (MRSA as causes of human infection and colonization in Germany.

    Directory of Open Access Journals (Sweden)

    Robin Köck

    Full Text Available Pigs, cattle and poultry are colonized with MRSA and the zoonotic transmission of such MRSA to humans via direct animal contact, environmental contaminations or meat are a matter of concern. Livestock-associated (LA MRSA are mostly belonging to clonal complex (CC 398 as defined by multilocus sequence typing. However, MRSA of other clonal lineages including CC5, CC9 and CC97 have also been detected in livestock animals in Germany. Within the framework of a Dutch-German network project (EUREGIO, 14,036 MRSA isolated from clinical and screening specimens (January 2008 - June 2012 derived from human patients in hospitals as well as general or specialized practices in a German region characterized by a high density of livestock production, were subjected to S. aureus protein A (spa sequence typing. The prevalence of putative LA-MRSA among the human MRSA isolates was determined by analyzing the detection of livestock-indicator (LI spa types which had already been reported in German livestock. Overall, 578 spa types were detected among the MRSA isolates. LI spa types t011, t034, t108, t1451, t2011, t571, t1456, t1250, t1255, t1580, t2970, t2346, t1344, t2576, t2330 and t2510 (all of which are indicative for LA-MRSA CC398 accounted for 18.6% of all human isolates. The LI spa types t1430 (CC9, t3992 (CC97, t002 (CC5 and t007 (CC30 were found in 0.14%, 0.01%, 1.01% and 0.04% of all human MRSA isolates, respectively. LI spa types associated with CC398 represented 23% of all MRSA from screening samples and a varying proportion among isolates from clinical specimens ranging between 0% in cerebrospinal fluid, 8% in blood cultures and 14% in deep respiratory fluids. Our findings indicate that LA-MRSA are a major cause for human infection and stress the need for close surveillance. Although LA-MRSA CC398 predominates, the occurrence of putative LA-MRSA from other clonal lineages should be monitored.

  12. Changing epidemiology of pediatric Staphylococcus aureus bacteremia in Denmark from 1971 through 2000

    DEFF Research Database (Denmark)

    Frederiksen, Marianne Sjølin; Espersen, Frank; Frimodt-Møller, Niels;

    2007-01-01

    BACKGROUND: Staphylococcus aureus is known to be a leading cause of bacteremia in childhood, and is associated with severe morbidity and increased mortality. To determine developments in incidence and mortality rates, as well as risk factors associated with outcome, we analyzed data from 1971...... through 2000. METHODS: Nationwide registration of S. aureus bacteremia (SAB) among children and adolescents from birth to 20 years of age was performed. Data on age, sex, source of bacteremia, comorbidity and outcome were extracted from discharge records. Rates were population adjusted and risk factors...... and improved treatment modalities. However, incidence rates have increased significantly in the same period, underscoring that S. aureus remains an important invasive pathogen....

  13. Possible healthcare-associated transmission as a cause of secondary infection and population structure of Staphylococcus aureus isolates from two wound treatment centres in Ghana.

    Science.gov (United States)

    Kpeli, G; Darko Otchere, I; Lamelas, A; Buultjens, A L; Bulach, D; Baines, S L; Seemann, T; Giulieri, S; Nakobu, Z; Aboagye, S Y; Owusu-Mireku, E; Pluschke, G; Stinear, T P; Yeboah-Manu, D

    2016-09-01

    We have previously shown that secondary infections of Buruli ulcer wounds were frequently caused by Staphylococcus aureus. To gain understanding into possible routes of secondary infection, we characterized S. aureus isolates from patient lesions and surrounding environments across two Ghanaian health centres. One hundred and one S. aureus isolates were isolated from wounds (n = 93, 92.1%) and the hospital environment (n = 8, 7.9%) and characterized by the spa gene, mecA and the Panton-Valentine leucocidin toxin followed by spa sequencing and whole genome sequencing of a subset of 49 isolates. Spa typing and sequencing of the spa gene from 91 isolates identified 29 different spa types with t355 (ST152), t186 (ST88), and t346 dominating. Although many distinct strains were isolated from both health centres, genotype clustering was identified within centres. In addition, we identified a cluster consisting of isolates from a healthcare worker, patients dressed that same day and forceps used for dressing, pointing to possible healthcare-associated transmission. These clusters were confirmed by phylogenomic analysis. Twenty-four (22.8%) isolates were identified as methicillin-resistant S. aureus and lukFS genes encoding Panton-Valentine leucocidin were identified in 67 (63.8%) of the isolates. Phenotype screening showed widespread resistance to tetracycline, erythromycin, rifampicin, amikacin and streptomycin. Genomics confirmed the widespread presence of antibiotic resistance genes to β-lactams, chloramphenicol, trimethoprim, quinolone, streptomycin and tetracycline. Our findings indicate that the healthcare environment probably contributes to the superinfection of Buruli ulcer wounds and calls for improved training in wound management and infection control techniques. PMID:27547406

  14. Meticillin-resistant Staphylococcus aureus CC398 is an increasing cause of disease in people with no livestock contact in Denmark, 1999 to 2011

    DEFF Research Database (Denmark)

    Larsen, J.; Petersen, A.; Sørum, M.;

    2015-01-01

    Livestock constitutes a potential reservoir of meticillin-resistant Staphylococcus aureus isolates belonging to a recently derived lineage within clonal complex 398 (MRSA CC398-IIa). Since its discovery in the early 2000s, this lineage has become a major cause of human disease in Europe, posing a...... serious public health challenge in countries with intensive livestock production. To retrace the history of human colonisation and infection with MRSA CC398-IIa in Denmark, we conducted a nationwide, retrospective study of MRSA isolates collected from 1999 to 2011. Among 7,429 MRSA isolates screened, we...

  15. Characterization of erythromycin-resistant Streptococcus pneumoniae isolates causing invasive diseases in Chinese children

    Institute of Scientific and Technical Information of China (English)

    MA Xiang; YAO Kai-hu; XIE Gui-lin; ZHENG YUE-jie; WANG Chuan-qing; SHANG Yun-xiao; WANG Hui-yun

    2013-01-01

    Background Erythromycin-resistant Streptococcus pneumoniae isolates that causing invasive pneumococcal diseases (IPD) in Chinese children remain uncharacterized.This study aims to identify the resistance genes associated with erythromycin resistance and to determine the genetic relationships of IPD isolates in Chinese children.Methods A total of 171 S.pneumoniae strains were isolated from 11 medical centers in China from 2006 to 2008.All the isolates were characterized via serotyping and antibiotic susceptibility determination.The erythromycin-resistant isolates were further characterized via ermB and mefA gene detection,multi-locus sequence typing analysis,and pulsed-field gel electrophoresis.Results A total of 164 (95.9%) isolates showed resistance to erythromycin,of which 162 strains with high high-level resistance (MIC ≥ 256 μg/ml).A total of 104 (63.4%) isolates carry the ermB gene alone,whereas 59 (36.0%) harbor both ermB and mefA genes.Of the 59 strains,54 were of serotypes 19A and 19F and were identified as highly clonal and related to the Taiwan19F-14 clone.Conclusions The erythromycin resistance rate in IPD isolates is significantly high and is predominantly mediated by the ermB gene.Isolates that carry both ermB and mefA genes are predominantly of serotypes 19A and 19F.

  16. Extracellular matrix formation enhances the ability of Streptococcus pneumoniae to cause invasive disease.

    Directory of Open Access Journals (Sweden)

    Claudia Trappetti

    Full Text Available During infection, pneumococci exist mainly in sessile biofilms rather than in planktonic form, except during sepsis. However, relatively little is known about how biofilms contribute to pneumococcal pathogenesis. Here, we carried out a biofilm assay on opaque and transparent variants of a clinical serotype 19F strain WCH159. After 4 days incubation, scanning electron microscopy revealed that opaque biofilm bacteria produced an extracellular matrix, whereas the transparent variant did not. The opaque biofilm-derived bacteria translocated from the nasopharynx to the lungs and brain of mice, and showed 100-fold greater in vitro adherence to A549 cells than transparent bacteria. Microarray analysis of planktonic and sessile bacteria from transparent and opaque variants showed differential gene expression in two operons: the lic operon, which is involved in choline uptake, and in the two-component system, ciaRH. Mutants of these genes did not form an extracellular matrix, could not translocate from the nasopharynx to the lungs or the brain, and adhered poorly to A549 cells. We conclude that only the opaque phenotype is able to form extracellular matrix, and that the lic operon and ciaRH contribute to this process. We propose that during infection, extracellular matrix formation enhances the ability of pneumococci to cause invasive disease.

  17. The climate change caused by the land plant invasion in the Devonian

    Science.gov (United States)

    Le Hir, Guillaume; Donnadieu, Yannick; Goddéris, Yves; Meyer-Berthaud, Brigitte; Ramstein, Gilles; Blakey, Ronald C.

    2011-10-01

    Land plants invaded continents during the Mid-Paleozoic. Their spreading and diversification have been compared to the Cambrian explosion in terms of intensity and impact on the diversification of life on Earth. Whereas prior studies were focused on the evolution of the root system and its weathering contribution, here we used a coupled climate/carbon/vegetation model to investigate the biophysical impacts of plant colonization on the surface climate through changes in continental albedo, roughness, thermal properties, and potential evaporation. From the Early to the Late Devonian, our model simulates a significant atmospheric CO 2 drop from 6300 to 2100 ppmv that is due to an increase in the consumption of CO 2 though continental silicate weathering. The continental drift and the climatic changes promoted by land plants explain this trend. The simulated CO 2 drawdown is paradoxically associated with unchanged temperatures. We show here that the CO 2 drop is counteracted by a large warming resulting from the surface albedo reduction caused by the appearance of an extended plant-cover. If CO 2 is consensually assumed as the main driver of the Phanerozoic climate, this paper demonstrates that, during land-plant invasion, the modifications of soil properties could have played in the opposite direction of the carbon dioxide fall, hence maintaining warm temperatures during part of the Devonian.

  18. Suppressing TGFβ signaling in regenerating epithelia in an inflammatory microenvironment is sufficient to cause invasive intestinal cancer.

    Science.gov (United States)

    Oshima, Hiroko; Nakayama, Mizuho; Han, Tae-Su; Naoi, Kuniko; Ju, Xiaoli; Maeda, Yusuke; Robine, Sylvie; Tsuchiya, Kiichiro; Sato, Toshiro; Sato, Hiroshi; Taketo, Makoto Mark; Oshima, Masanobu

    2015-02-15

    Genetic alterations in the TGFβ signaling pathway in combination with oncogenic alterations lead to cancer development in the intestines. However, the mechanisms of TGFβ signaling suppression in malignant progression of intestinal tumors have not yet been fully understood. We have examined Apc(Δ716) Tgfbr2(ΔIEC) compound mutant mice that carry mutations in Apc and Tgfbr2 genes in the intestinal epithelial cells. We found inflammatory microenvironment only in the invasive intestinal adenocarcinomas but not in noninvasive benign polyps of the same mice. We thus treated simple Tgfbr2(ΔIEC) mice with dextran sodium sulfate (DSS) that causes ulcerative colitis. Importantly, these Tgfbr2(ΔIEC) mice developed invasive colon cancer associated with chronic inflammation. We also found that TGFβ signaling is suppressed in human colitis-associated colon cancer cells. In the mouse invasive tumors, macrophages infiltrated and expressed MT1-MMP, causing MMP2 activation. These results suggest that inflammatory microenvironment contributes to submucosal invasion of TGFβ signaling-repressed epithelial cells through activation of MMP2. We further found that regeneration was impaired in Tgfbr2(ΔIEC) mice for intestinal mucosa damaged by DSS treatment or X-ray irradiation, resulting in the expansion of undifferentiated epithelial cell population. Moreover, organoids of intestinal epithelial cells cultured from irradiated Tgfbr2(ΔIEC) mice formed "long crypts" in Matrigel, suggesting acquisition of an invasive phenotype into the extracellular matrix. These results, taken together, indicate that a simple genetic alteration in the TGFβ signaling pathway in the inflamed and regenerating intestinal mucosa can cause invasive intestinal tumors. Such a mechanism may play a role in the colon carcinogenesis associated with inflammatory bowel disease in humans.

  19. Acute haematogenous community-acquired methicillin-resistant Staphylococcus aureus osteomyelitis in an adult: Case report and review of literature

    OpenAIRE

    Dhanoa Amreeta; Singh Vivek; Mansor Azura; Yusof Mohd; Lim King-Ting; Thong Kwai-Lin

    2012-01-01

    Abstract Background Methicillin-resistant Staphylococcus aureus (MRSA) has of late emerged as a cause of community-acquired infections among immunocompetent adults without risk factors. Skin and soft tissue infections represent the majority of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) clinical presentations, whilst invasive and life-threatening illness like necrotizing pneumonia, necrotizing fasciitis, pyomyositis, osteomyelitis and sepsis syndrome are less comm...

  20. Comparison of community-onset Staphylococcus argenteus and Staphylococcus aureus sepsis in Thailand: a prospective multicentre observational study

    OpenAIRE

    Chantratita, N.; Wikraiphat, C; Tandhavanant, S.; Wongsuvan, G; Ariyaprasert, P.; Suntornsut, P; Thaipadungpanit, J; Teerawattanasook, N.; Jutrakul, Y.; Srisurat, N; Chaimanee, P; Anukunananchai, J.; Phiphitaporn, S; Srisamang, P; Chetchotisakd, P

    2016-01-01

    Staphylococcus argenteus is a globally distributed cause of human infection, but diagnostic laboratories misidentify this as Staphylococcus aureus. We determined whether there is clinical utility in distinguishing between the two. A prospective cohort study of community-onset invasive staphylococcal sepsis was conducted in adults at four hospitals in northeast Thailand between 2010 and 2013. Of 311 patients analysed, 58 (19%) were infected with S. argenteus and 253 (81%) with S. aureus. Most ...

  1. Gene expression analysis of children with acute hematogenous osteomyelitis caused by Methicillin-resistant Staphylococcus aureus: correlation with clinical severity of illness.

    Directory of Open Access Journals (Sweden)

    Claudia Gaviria-Agudelo

    Full Text Available Children with acute hematogenous osteomyelitis (AHO demonstrate a broad spectrum of clinical manifestations, ranging from mild to severe. Several advances have been achieved in the study of host immune response to acute invasive Staphylococcus aureus infections through gene expression analysis. However, previous research has neither attempted to evaluate the response of children with AHO specific to Methicillin-resistant Staphylococcus aureus (MRSA nor to correlate gene expression with clinical phenotype. Study objective was to correlate gene expression of children with AHO due to MRSA with clinical severity of illness. Whole blood samples were obtained in Tempus tubes from 12 children with osteomyelitis once cultures obtained directly from the site of infection confirmed to be positive for MRSA. Using an Illumina platform and a systems-wide modular analysis, microarray findings from ten of these children were compared to that of nine healthy (age, ethnicity and gender matched controls and correlated with clinical severity of illness. Children with AHO from MRSA demonstrated over-expression of innate immunity with respect to neutrophil activity, coagulation, inflammatory response, and erythrocyte development. Concurrently, these children demonstrated under-expression of adaptive immunity with respect to lymphocyte activation and activity of T-cell, cytotoxic or NK cell, and B-cell lines. Three over-expressed genes, P2RX1, SORT1, and RETN, and two under-expressed genes, LOC641788 and STAT 4, were significantly correlated with severity of illness. STAT 4 showed the strongest correlation (R2 = -0.83. STAT4 downregulation could potentially explain under-expression of genes related to adaptive immunity in this cohort of patients with AHO. This study identified specific genes which correspond to disease severity during the early hospitalization of children with AHO from MRSA. Pattern recognition of this combination of genes could help to identify

  2. Unexplained exertional dyspnea caused by low ventricular filling pressures: results from clinical invasive cardiopulmonary exercise testing.

    Science.gov (United States)

    Oldham, William M; Lewis, Gregory D; Opotowsky, Alexander R; Waxman, Aaron B; Systrom, David M

    2016-03-01

    To determine whether low ventricular filling pressures are a clinically relevant etiology of unexplained dyspnea on exertion, a database of 619 consecutive, clinically indicated invasive cardiopulmonary exercise tests (iCPETs) was reviewed to identify patients with low maximum aerobic capacity (V̇o2max) due to inadequate peak cardiac output (Qtmax) with normal biventricular ejection fractions and without pulmonary hypertension (impaired: n = 49, V̇o2max = 53% predicted [interquartile range (IQR): 47%-64%], Qtmax = 72% predicted [62%-76%]). These were compared to patients with a normal exercise response (normal: n = 28, V̇o2max = 86% predicted [84%-97%], Qtmax = 108% predicted [97%-115%]). Before exercise, all patients received up to 2 L of intravenous normal saline to target an upright pulmonary capillary wedge pressure (PCWP) of ≥5 mmHg. Despite this treatment, biventricular filling pressures at peak exercise were lower in the impaired group than in the normal group (right atrial pressure [RAP]: 6 [IQR: 5-8] vs. 9 [7-10] mmHg, P = 0.004; PCWP: 12 [10-16] vs. 17 [14-19] mmHg, P volume (SV) augmentation with exercise (+13 ± 10 [standard deviation (SD)] vs. +18 ± 10 mL/m(2), P = 0.014). A review of hemodynamic data from 23 patients with low RAP on an initial iCPET who underwent a second iCPET after saline infusion (2.0 ± 0.5 L) demonstrated that 16 of 23 patients responded with increases in Qtmax ([+24% predicted [IQR: 14%-34%]), V̇o2max (+10% predicted [7%-12%]), and maximum SV (+26% ± 17% [SD]). These data suggest that inadequate ventricular filling related to low venous pressure is a clinically relevant cause of exercise intolerance. PMID:27162614

  3. Unexplained exertional dyspnea caused by low ventricular filling pressures: results from clinical invasive cardiopulmonary exercise testing

    Science.gov (United States)

    Lewis, Gregory D.; Opotowsky, Alexander R.; Waxman, Aaron B.; Systrom, David M.

    2016-01-01

    Abstract To determine whether low ventricular filling pressures are a clinically relevant etiology of unexplained dyspnea on exertion, a database of 619 consecutive, clinically indicated invasive cardiopulmonary exercise tests (iCPETs) was reviewed to identify patients with low maximum aerobic capacity (V̇o2max) due to inadequate peak cardiac output (Qtmax) with normal biventricular ejection fractions and without pulmonary hypertension (impaired: n = 49, V̇o2max = 53% predicted [interquartile range (IQR): 47%–64%], Qtmax = 72% predicted [62%–76%]). These were compared to patients with a normal exercise response (normal: n = 28, V̇o2max = 86% predicted [84%–97%], Qtmax = 108% predicted [97%–115%]). Before exercise, all patients received up to 2 L of intravenous normal saline to target an upright pulmonary capillary wedge pressure (PCWP) of ≥5 mmHg. Despite this treatment, biventricular filling pressures at peak exercise were lower in the impaired group than in the normal group (right atrial pressure [RAP]: 6 [IQR: 5–8] vs. 9 [7–10] mmHg, P = 0.004; PCWP: 12 [10–16] vs. 17 [14–19] mmHg, P < 0.001), associated with decreased stroke volume (SV) augmentation with exercise (+13 ± 10 [standard deviation (SD)] vs. +18 ± 10 mL/m2, P = 0.014). A review of hemodynamic data from 23 patients with low RAP on an initial iCPET who underwent a second iCPET after saline infusion (2.0 ± 0.5 L) demonstrated that 16 of 23 patients responded with increases in Qtmax ([+24% predicted [IQR: 14%–34%]), V̇o2max (+10% predicted [7%–12%]), and maximum SV (+26% ± 17% [SD]). These data suggest that inadequate ventricular filling related to low venous pressure is a clinically relevant cause of exercise intolerance. PMID:27162614

  4. Reduced Susceptibility to Penicillin among Pneumococci Causing Invasive Infection in Children - Canada, 1991-1998

    OpenAIRE

    Scheifele, David; Halperin, Scott; Pelletier, Louise; Talbot, James; Lovgren, Marguerite; Vaudry, Wendy; Jadavji, Taj; Law, Barbara; MacDonald, Noni; Gold, Ron; Wang, Elaine; Mills, Elaine; LeBel, Marc; Déry, Pierre; Morris, Rob

    2001-01-01

    OBJECTIVE: To determine, over time, the rate and serotypes of pneumococci with reduced penicillin susceptibility obtained from children with invasive infection.DESIGN: Active, hospital-based, multicentre surveillance spanning from 1991 to 1998.SETTING: Eleven Canadian tertiary care paediatric facilities located from coast to coast.POPULATION STUDIED: 1847 children with invasive pneumococcal infection whose isolates (from a normally sterile site) were available for serotyping and standardized ...

  5. Invasion strategies in clonal aquatic plants: Are phenotypic differences caused by phenotypic plasticity or local adaptation?

    DEFF Research Database (Denmark)

    Riis, Tenna; Lambertini, Carla; Olesen, Birgit;

    2010-01-01

    Background and Aims: The successful spread of invasive plants in new environments is often linked to multiple introductions and a diverse gene pool that facilitates local adaptation to variable environmental conditions. For clonal plants, however, phenotypic plasticity may be equally important...... conditions and plant morphological characteristics. Conclusions: The results indicate that at the current stage of spread into New Zealand, the primary adaptive strategy of these three invasive macrophytes is phenotypic plasticity. However, while limited, the possibility that genetic diversity between...... populations may facilitate ecotypic differentiation in the future cannot be excluded. These results thus indicate that invasive clonal aquatic plants adapt to new introduced areas by phenotypic plasticity. Inorganic carbon, nitrogen and phosphorous were important in controlling plant size of E. canadensis...

  6. Invasive aspergillosis causing small bowel infarction in a patient of carcinoma breast undergoing chemotherapy

    Directory of Open Access Journals (Sweden)

    Jain Vinod

    2006-01-01

    Full Text Available Abstract Background To report a 45 year old lady presenting with proximal jejunal gangrene due to invasive Aspergillosis. The patient was undergoing adjuvant chemotherapy for advance carcinoma of breast (Stage IV. Methods The patient was referred to our surgical emergency for acute abdominal symptoms for 6 hours. Histopathology revealed bowel wall necrosis and vascular invasion by Aspergillus Fumigatus. Postoperative recovery was uneventful and the patient received Amphotericin-B (1 mg/kg/day for invasive aspergillosis. Invasive pulmonary aspergillosis was confirmed by isolating Aspergillus Fumigatus from bronchoalveolar lavage and by a positive circulating galactomannan test (ELISA Assay. Results Detailed history revealed dry cough and two episodes of haemoptesis for 2 weeks. Haemogram and counts revealed anemia and neutropenia. Plain X – ray of the abdomen showed multiple air fluid levels and ultrasound of the abdomen revealed distended bowel loops. On exploration small bowel was found to be gangrenous. The patient was successfully managed by supportive treatment and conventional intravenous Amphotericin-B for 2 weeks. The lady was discharged one week after completion of antifungal therapy and one month later she underwent toilet mastectomy. The lady came to follow up for 1 year and she is currently under hormone therapy. Conclusion With the emergence of new and powerful immunosuppressive, anticancer drugs and potent antibiotics the survival of transplant and critically ill patients has remarkably increased but it has shown a significant rise in the incidence of invasive opportunistic fungal infections. We conclude hat the diagnosis of invasive gastrointestinal aspergillosis may be considered in a neutropenic patient with acute abdominal symptoms.

  7. Neutrophil-generated oxidative stress and protein damage in Staphylococcus aureus.

    Science.gov (United States)

    Beavers, William N; Skaar, Eric P

    2016-08-01

    Staphylococcus aureus is a ubiquitous, versatile and dangerous pathogen. It colonizes over 30% of the human population, and is one of the leading causes of death by an infectious agent. During S. aureus colonization and invasion, leukocytes are recruited to the site of infection. To combat S. aureus, leukocytes generate an arsenal of reactive species including superoxide, hydrogen peroxide, nitric oxide and hypohalous acids that modify and inactivate cellular macromolecules, resulting in growth defects or death. When S. aureus colonization cannot be cleared by the immune system, antibiotic treatment is necessary and can be effective. Yet, this organism quickly gains resistance to each new antibiotic it encounters. Therefore, it is in the interest of human health to acquire a deeper understanding of how S. aureus evades killing by the immune system. Advances in this field will have implications for the design of future S. aureus treatments that complement and assist the host immune response. In that regard, this review focuses on how S. aureus avoids host-generated oxidative stress, and discusses the mechanisms used by S. aureus to survive oxidative damage including antioxidants, direct repair of damaged proteins, sensing oxidant stress and transcriptional changes. This review will elucidate areas for studies to identify and validate future antimicrobial targets.

  8. Neutrophil-generated oxidative stress and protein damage in Staphylococcus aureus.

    Science.gov (United States)

    Beavers, William N; Skaar, Eric P

    2016-08-01

    Staphylococcus aureus is a ubiquitous, versatile and dangerous pathogen. It colonizes over 30% of the human population, and is one of the leading causes of death by an infectious agent. During S. aureus colonization and invasion, leukocytes are recruited to the site of infection. To combat S. aureus, leukocytes generate an arsenal of reactive species including superoxide, hydrogen peroxide, nitric oxide and hypohalous acids that modify and inactivate cellular macromolecules, resulting in growth defects or death. When S. aureus colonization cannot be cleared by the immune system, antibiotic treatment is necessary and can be effective. Yet, this organism quickly gains resistance to each new antibiotic it encounters. Therefore, it is in the interest of human health to acquire a deeper understanding of how S. aureus evades killing by the immune system. Advances in this field will have implications for the design of future S. aureus treatments that complement and assist the host immune response. In that regard, this review focuses on how S. aureus avoids host-generated oxidative stress, and discusses the mechanisms used by S. aureus to survive oxidative damage including antioxidants, direct repair of damaged proteins, sensing oxidant stress and transcriptional changes. This review will elucidate areas for studies to identify and validate future antimicrobial targets. PMID:27354296

  9. Efficacy of Linezolid and Fosfomycin in Catheter-Related Biofilm Infection Caused by Methicillin-Resistant Staphylococcus aureus.

    Science.gov (United States)

    Chai, Dong; Liu, Xu; Wang, Rui; Bai, Yan; Cai, Yun

    2016-01-01

    As long-standing clinical problems, catheter-related infections and other chronic biofilm infections are more difficult to treat due to the high antibiotic resistance of biofilm. Therefore, new treatments are needed for more effective bacteria clearance. In this study, we evaluated the antibacterial activities of several common antibiotics alone and their combinations against biofilm-embedded methicillin-resistant staphylococcus aureus (MRSA) infections, both in vitro and in vivo. In brief, fosfomycin, levofloxacin, and rifampin alone or in combination with linezolid were tested in vitro against planktonic and biofilm-embedded MRSA infection in three MRSA stains. The synergistic effects between linezolid and the other three antibiotics were assessed by fractional inhibitory concentration index (FICI) and time-kill curves, where the combination of linezolid plus fosfomycin showed the best synergistic effect in all strains. For further evaluation in vivo, we applied the combination of linezolid and fosfomycin in a catheter-related biofilm rat model and found that viable bacteria counts in biofilm were significantly reduced after treatment (P fosfomycin treatment had improved therapeutic effects on biofilm-embedded MRSA infection both in vitro and in vivo, which provided important basis for new clinical therapy development. PMID:27366751

  10. Efficacy of Linezolid and Fosfomycin in Catheter-Related Biofilm Infection Caused by Methicillin-Resistant Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Dong Chai

    2016-01-01

    Full Text Available As long-standing clinical problems, catheter-related infections and other chronic biofilm infections are more difficult to treat due to the high antibiotic resistance of biofilm. Therefore, new treatments are needed for more effective bacteria clearance. In this study, we evaluated the antibacterial activities of several common antibiotics alone and their combinations against biofilm-embedded methicillin-resistant staphylococcus aureus (MRSA infections, both in vitro and in vivo. In brief, fosfomycin, levofloxacin, and rifampin alone or in combination with linezolid were tested in vitro against planktonic and biofilm-embedded MRSA infection in three MRSA stains. The synergistic effects between linezolid and the other three antibiotics were assessed by fractional inhibitory concentration index (FICI and time-kill curves, where the combination of linezolid plus fosfomycin showed the best synergistic effect in all strains. For further evaluation in vivo, we applied the combination of linezolid and fosfomycin in a catheter-related biofilm rat model and found that viable bacteria counts in biofilm were significantly reduced after treatment (P<0.05. In summary, we have shown here that the combination of linezolid and fosfomycin treatment had improved therapeutic effects on biofilm-embedded MRSA infection both in vitro and in vivo, which provided important basis for new clinical therapy development.

  11. Spontaneous septic arthritis of the lumbar facet caused by methicillin-resistant Staphylococcus aureus in an otherwise healthy adolescent.

    Science.gov (United States)

    Papaliodis, Dean N; Roberts, Timothy T; Richardson, Nicholas G; Lawrence, James B

    2014-07-01

    We report the case of a 16-year-old boy with isolated septic arthritis of a lumbar facet. This rare presentation of an infection in a lumbar facet joint occurred after minor trauma sustained in a football game. Septic arthritis of the spinal facet joint is an uncommon phenomenon. Only 5 cases have been reported in immunocompromised pediatric patients. To our knowledge, no case of septic arthritis in an immunocompetent pediatric patient has been reported. An otherwise healthy 16-year-old boy presented with 4 weeks of escalating back pain after a minor athletics-related trauma. Evaluation showed incapacitating pain, lumbar musculature spasms, and the absence of fever, hemodynamic, or neurologic changes. Laboratory values were within normal limits. Magnetic resonance images showed a fluid collection within the L3-L4 facet and a localized abscess. Computed tomographic-guided aspiration showed methicillin-resistant Staphylococcus aureus infection, for which the patient received 6 weeks of vancomycin with complete resolution of symptoms. Refractory lumbago in an adolescent requires careful evaluation.

  12. Comparison of cefazolin versus oxacillin for treatment of complicated bacteremia caused by methicillin-susceptible Staphylococcus aureus.

    Science.gov (United States)

    Li, Julius; Echevarria, Kelly L; Hughes, Darrel W; Cadena, Jose A; Bowling, Jason E; Lewis, James S

    2014-09-01

    Contrary to prior case reports that described occasional clinical failures with cefazolin for methicillin-susceptible Staphylococcus aureus (MSSA) infections, recent studies have demonstrated no difference in outcomes between cefazolin and antistaphylococcal penicillins for the treatment of MSSA bacteremia. While promising, these studies described low frequencies of high-inoculum infections, such as endocarditis. This retrospective study compares clinical outcomes of cefazolin versus oxacillin for complicated MSSA bacteremia at two tertiary care hospitals between January 2008 and June 2012. Fifty-nine patients treated with cefazolin and 34 patients treated with oxacillin were included. Osteoarticular (41%) and endovascular (20%) sources were the predominant sites of infection. The rates of clinical cure at the end of therapy were similar between cefazolin and oxacillin (95% versus 88%; P=0.25), but overall failure at 90 days was higher in the oxacillin arm (47% versus 24%; P=0.04). Failures were more likely to have received surgical interventions (63% versus 40%; P=0.05) and to have an osteoarticular source (57% versus 33%; P=0.04). Failures also had a longer duration of bacteremia (7 versus 3 days; P=0.0002), which was the only predictor of failure. Antibiotic selection was not predictive of failure. Rates of adverse drug events were higher in the oxacillin arm (30% versus 3%; P=0.0006), and oxacillin was more frequently discontinued due to adverse drug events (21% versus 3%; P=0.01). Cefazolin appears similar to oxacillin for the treatment of complicated MSSA bacteremia but with significantly improved safety. The higher rates of failure with oxacillin may have been confounded by other patient factors and warrant further investigation. PMID:24936596

  13. Unexplained exertional dyspnea caused by low ventricular filling pressures: results from clinical invasive cardiopulmonary exercise testing

    OpenAIRE

    Oldham, William M.; Lewis, Gregory D.; Opotowsky, Alexander R.; Waxman, Aaron B.; Systrom, David M.

    2016-01-01

    To determine whether low ventricular filling pressures are a clinically relevant etiology of unexplained dyspnea on exertion, a database of 619 consecutive, clinically indicated invasive cardiopulmonary exercise tests (iCPETs) was reviewed to identify patients with low maximum aerobic capacity (V̇o2max) due to inadequate peak cardiac output (Qtmax) with normal biventricular ejection fractions and without pulmonary hypertension (impaired: n = 49, V̇o2max = 53% predicted [interquartile range (I...

  14. Invasion strategies in clonal aquatic plants: are phenotypic differences caused by phenotypic plasticity or local adaptation?

    Science.gov (United States)

    Riis, Tenna; Lambertini, Carla; Olesen, Birgit; Clayton, John S.; Brix, Hans; Sorrell, Brian K.

    2010-01-01

    Background and Aims The successful spread of invasive plants in new environments is often linked to multiple introductions and a diverse gene pool that facilitates local adaptation to variable environmental conditions. For clonal plants, however, phenotypic plasticity may be equally important. Here the primary adaptive strategy in three non-native, clonally reproducing macrophytes (Egeria densa, Elodea canadensis and Lagarosiphon major) in New Zealand freshwaters were examined and an attempt was made to link observed differences in plant morphology to local variation in habitat conditions. Methods Field populations with a large phenotypic variety were sampled in a range of lakes and streams with different chemical and physical properties. The phenotypic plasticity of the species before and after cultivation was studied in a common garden growth experiment, and the genetic diversity of these same populations was also quantified. Key Results For all three species, greater variation in plant characteristics was found before they were grown in standardized conditions. Moreover, field populations displayed remarkably little genetic variation and there was little interaction between habitat conditions and plant morphological characteristics. Conclusions The results indicate that at the current stage of spread into New Zealand, the primary adaptive strategy of these three invasive macrophytes is phenotypic plasticity. However, while limited, the possibility that genetic diversity between populations may facilitate ecotypic differentiation in the future cannot be excluded. These results thus indicate that invasive clonal aquatic plants adapt to new introduced areas by phenotypic plasticity. Inorganic carbon, nitrogen and phosphorous were important in controlling plant size of E. canadensis and L. major, but no other relationships between plant characteristics and habitat conditions were apparent. This implies that within-species differences in plant size can be explained

  15. Spontaneous gastric ulcer perforation and acute spleen infarction caused by invasive gastric and splenic mucormycosis

    Directory of Open Access Journals (Sweden)

    Mushira Abdulaziz Enani

    2014-01-01

    Full Text Available Mucormycosis is a rare life-threatening fungal infection mostly affecting immunocompromised hosts. The main categories of human disease with the Mucorales are sinusitis/rhinocerebral, pulmonary, cutaneous/subcutaneous, gastrointestinal and disseminated disease. Other disease states occur with a much lower frequency and include cystitis, vaginitis; external otitis and allergic disease. We report a diabetic patient with comorbidities, who developed gastric perforation clinically indistinguishable from perforated peptic ulcer due to invasive gastric mucormycosis complicated by spleen infarction.

  16. Spontaneous gastric ulcer perforation and acute spleen infarction caused by invasive gastric and splenic mucormycosis.

    Science.gov (United States)

    Enani, Mushira Abdulaziz; Alharthi, Bandar N; Dewanjee, Nancy; Bhat, Nadeem A; Fagih, Mosa

    2014-07-01

    Mucormycosis is a rare life-threatening fungal infection mostly affecting immunocompromised hosts. The main categories of human disease with the Mucorales are sinusitis/rhinocerebral, pulmonary, cutaneous/subcutaneous, gastrointestinal and disseminated disease. Other disease states occur with a much lower frequency and include cystitis, vaginitis; external otitis and allergic disease. We report a diabetic patient with comorbidities, who developed gastric perforation clinically indistinguishable from perforated peptic ulcer due to invasive gastric mucormycosis complicated by spleen infarction.

  17. Repositioning "old" drugs for new causes: identifying new inhibitors of prostate cancer cell migration and invasion.

    Science.gov (United States)

    Shah, Esha T; Upadhyaya, Akanksha; Philp, Lisa K; Tang, Tiffany; Skalamera, Dubravka; Gunter, Jennifer; Nelson, Colleen C; Williams, Elizabeth D; Hollier, Brett G

    2016-04-01

    The majority of prostate cancer (PCa) deaths occur due to the metastatic spread of tumor cells to distant organs. Currently, there is a lack of effective therapies once tumor cells have spread outside the prostate. It is therefore imperative to rapidly develop therapeutics to inhibit the metastatic spread of tumor cells. Gain of cell motility and invasive properties is the first step of metastasis and by inhibiting motility one can potentially inhibit metastasis. Using the drug repositioning strategy, we developed a cell-based multi-parameter primary screening assay to identify drugs that inhibit the migratory and invasive properties of metastatic PC-3 PCa cells. Following the completion of the primary screening assay, 33 drugs were identified from an FDA approved drug library that either inhibited migration or were cytotoxic to the PC-3 cells. Based on the data obtained from the subsequent validation studies, mitoxantrone hydrochloride, simvastatin, fluvastatin and vandetanib were identified as strong candidates that can inhibit both the migration and invasion of PC-3 cells without significantly affecting cell viability. By employing the drug repositioning strategy instead of a de novo drug discovery and development strategy, the identified drug candidates have the potential to be rapidly translated into the clinic for the management of men with aggressive forms of PCa.

  18. The importance of subcutaneous abscess infection by Pasteurella spp. and Staphylococcus aureus as a cause of meat condemnation in slaughtered commercial rabbits

    Directory of Open Access Journals (Sweden)

    A. Ferreira

    2014-12-01

    Full Text Available Subcutaneous abscesses are lesions frequently reported in commercial rabbits. Both at farm and slaughterhouse level, these lesions are responsible for economic losses and a potential decrease in meat quality. The present study was devised to identify the main causes of meat condemnation in slaughtered commercial rabbits and assess the importance of abscess lesions in this domain. For these purposes, 281423 rabbits were evaluated during meat inspection at the slaughterhouse. The results achieved showed that subcutaneous abscesses were the major cause of condemnation, being responsible for the rejection of 1355 (0.48% rabbit carcasses. The main affected area was the hind limbs (31.37%, followed by the cervical area (23.10%. Microbiological analyses of 27 abscess samples indicated Pasteurella spp. as the bacteria mostly isolated (59.3%, followed by Staphylococcus aureus (25.9%. These results enable us to advise the industry on the significance of abscesses as an important cause of economic losses, due to meat condemnation during post mortem inspection, and highlight the importance of implementing monitoring plans as a way to control this pathological problem.

  19. Adult-onset Invasive Haemophilus influenzae Type f Caused by Acute Lower Leg Cellulitis.

    Science.gov (United States)

    Usui, Yuko; Kakuta, Risako; Araki, Makoto; Sato, Taigo; Gu, Yoshiaki; Yano, Hisakazu; Taniuchi, Norihide

    2016-01-01

    In Japan, routine Haemophilus influenzae type b (Hib) vaccination began in 2013. Thus, similar to other countries, a strain shift is expected in the near future. We experienced a case of H. influenzae type f (Hif) bacteremia in a 66-year-old man. The primary focus of the infection was the soft tissue of the left lower leg, which is an extremely rare origin in adults. Subsequently, we conducted multilocus sequence typing and identified the strain as sequence type 124, which is the most common invasive strain of Hif worldwide. This case may mark the beginning of an Hif strain shift in Japan. PMID:27374690

  20. Promotion of cancer cell invasiveness and metastasis emergence caused by olfactory receptor stimulation.

    Directory of Open Access Journals (Sweden)

    Guenhaël Sanz

    Full Text Available Olfactory receptors (ORs are expressed in the olfactory epithelium, where they detect odorants, but also in other tissues with additional functions. Some ORs are even overexpressed in tumor cells. In this study, we identified ORs expressed in enterochromaffin tumor cells by RT-PCR, showing that single cells can co-express several ORs. Some of the receptors identified were already reported in other tumors, but they are orphan (without known ligand, as it is the case for most of the hundreds of human ORs. Thus, genes coding for human ORs with known ligands were transfected into these cells, expressing functional heterologous ORs. The in vitro stimulation of these cells by the corresponding OR odorant agonists promoted cell invasion of collagen gels. Using LNCaP prostate cancer cells, the stimulation of the PSGR (Prostate Specific G protein-coupled Receptor, an endogenously overexpressed OR, by β-ionone, its odorant agonist, resulted in the same phenotypic change. We also showed the involvement of a PI3 kinase γ dependent signaling pathway in this promotion of tumor cell invasiveness triggered by OR stimulation. Finally, after subcutaneous inoculation of LNCaP cells into NSG immunodeficient mice, the in vivo stimulation of these cells by the PSGR agonist β-ionone significantly enhanced metastasis emergence and spreading.

  1. Increase in IS256 transposition in invasive vancomycin heteroresistant Staphylococcus aureus isolate belonging to ST100 and its derived VISA mutants.

    Science.gov (United States)

    Di Gregorio, Sabrina; Fernandez, Silvina; Perazzi, Beatriz; Bello, Natalia; Famiglietti, Angela; Mollerach, Marta

    2016-09-01

    In Staphylococcus aureus, transposition of IS256 has been described to play an important role in biofilm formation and antibiotic resistance. This study describes the molecular characterization of two clinical heterogeneous vancomycin-intermediate S. aureus (hVISA) isolates recovered from the same patient (before and after antibiotic treatment) and two VISA derivatives obtained by serial passages in the presence of vancomycin. Our results showed that antibiotic treatment (in vivo and in vitro) could enhance IS256 transposition, being responsible for the eventual loss of agr function. As far as we know this is the first study that reports the increase of IS256 transposition in isogenic strains after antibiotic treatment in a clinical setting. PMID:27154328

  2. Cytokine and acute phase protein mRNA expression in liver tissue from pigs with severe sepsis caused by intravenous inoculation of Staphylococcus aureus

    DEFF Research Database (Denmark)

    Nielsen, Ole Lerberg; Olsen, Helle Gerda; Iburg, Tine;

    2010-01-01

    The aim was to substantiate previous findings of hepatic dysfunction in a porcine model of Staphylococcus aureus induced severe sepsis. Nine pigs were inoculated intravenously once or twice with 108S. aureus per kilogram body weight and killed 12, 24 and 48 h later. Three pigs served as controls...

  3. Stricture caused by a plastic vascular clip used during an operation of minimally invasive esophagectomy.

    Science.gov (United States)

    Wójcik, Janusz; Grodzki, Tomasz; Kubisa, Bartosz; Pieróg, Jaroslaw

    2011-10-01

    This article describes the case of a 62-year-old female who had had minimally invasive esophagectomy (Ivor-Lewis) for squamous cell carcinoma of the distal third of the esophagus. The anastomotic stenosis was accompanied by solid food dysphagia and the presence of a foreign body in the esophagus. The foreign body was fixed to the esophageal wall and could not be removed endoscopically. The patient was reoperated on through a 8 cm right thoracotomy. The anastomosis was reached via a gastrotomy, and the large-size plastic vascular clip was removed. The clip was primarily used to close the transsected azygos vein, it was then incorporated into the esophageal anastomotic region and subsequently partially protruded into the lumen of the gastrointestinal tract. After removal of the clip, backward dilatation of the anastomosis was performed by Savary-Gilliard dilators, with restoration of its proper diameter. PMID:21798890

  4. Host-adaptive evolution of Staphylococcus aureus

    OpenAIRE

    Lowder, Bethan Victoria

    2011-01-01

    Staphylococcus aureus is a notorious human pathogen associated with severe nosocomial and community-acquired infections. In addition, S. aureus is a major cause of animal diseases including skeletal infections of poultry and bovine and ovine mastitis, which are a large economic burden on the broiler chicken and dairy farming industries. The population structure of S. aureus associated with humans has been well studied. However, despite the prevalence of S. aureus infections in ...

  5. Intracellular persisting Staphylococcus aureus is the major pathogen in recurrent tonsillitis.

    Directory of Open Access Journals (Sweden)

    Andreas E Zautner

    Full Text Available BACKGROUND: The two major indications for tonsillectomy are recurrent tonsillitis (RT and peritonsillar abscess (PTA. Unlike PTAs, which are primarily treated surgically, RT is often cured by tonsillectomy only after a series of failed drug therapy attempts. Although the bacteriological background of RT has been studied, the reason for the lack of success of conservative therapeutic approaches is not well understood. METHODS: In a prospective study, tonsil specimens from 130 RT patients and 124 PTA patients were examined for the presence of extra- and intracellular bacteria using antibiotic protection assays. Staphylococcus aureus isolates from RT patients were characterized by pulsed-field gel electrophoresis (PFGE, spa-typing and MSCRAMM-gene-PCR. Their ability for biofilm formation was tested and their cell invasiveness was confirmed by a flow cytometric invasion assay (FACS, fluorescent in situ hybridization (FISH and immunohistochemistry. FINDINGS: S. aureus was the predominant species (57.7% in RT patients, whereas Streptococcus pyogenes was most prevalent (20.2% in PTA patients. Three different assays (FACS, FISH, antibiotic protection assay showed that nearly all RT-associated S. aureus strains were located inside tonsillar cells. Correspondingly, the results of the MSCRAMM-gene-PCRs confirmed that 87% of these S. aureus isolates were invasive strains and not mere colonizers. Based upon PFGE analyses of genomic DNA and on spa-gene typing the vast majority of the S. aureus isolates belonged to different clonal lineages. CONCLUSIONS: Our results demonstrate that intracellular residing S. aureus is the most common cause of RT and indicate that S. aureus uses this location to survive the effects of antibiotics and the host immune response. A German translation of the Abstract is provided as supplementary material (Abstract S1.

  6. Glycoproteins and Gal-GalNAc cause Cryptosporidium to switch from an invasive sporozoite to a replicative trophozoite.

    Science.gov (United States)

    Edwinson, Adam; Widmer, Giovanni; McEvoy, John

    2016-01-01

    The apicomplexan parasite Cryptosporidium causes cryptosporidiosis, a diarrheal disease that can become chronic and life threatening in immunocompromised and malnourished people. There is no effective drug treatment for those most at risk of severe cryptosporidiosis. The disease pathology is due to a repeated cycle of host cell invasion and parasite replication that amplifies parasite numbers and destroys the intestinal epithelium. This study aimed to better understand the Cryptosporidium replication cycle by identifying molecules that trigger the switch from invasive sporozoite to replicative trophozoite. Our approach was to treat sporozoites of Cryptosporidium parvum and Cryptosporidium hominis, the species causing most human cryptosporidiosis, with various media under axenic conditions and examine the parasites for rounding and nuclear division as markers of trophozoite development and replication, respectively. FBS had a concentration-dependent effect on trophozoite development in both species. Trophozoite development in C. parvum, but not C. hominis, was enhanced when RPMI supplemented with 10% FBS (RPMI-FBS) was conditioned by HCT-8 cells for 3h. The effect of non-conditioned and HCT-8 conditioned RPMI-FBS on trophozoite development was abrogated by proteinase K and sodium metaperiodate pretreatment, indicating a glycoprotein trigger. Cryptosporidium parvum and C. hominis trophozoite development also was triggered by Gal-GalNAc in a concentration-dependent manner. Cryptosporidium parvum replication was greatest following treatments with Gal-GalNAc, followed by conditioned RPMI-FBS and non-conditioned RPMI-FBS (PGalNAc (1mM).

  7. Pediatric invasive pneumococcal disease caused by vaccine serotypes following the introduction of conjugate vaccination in Denmark

    DEFF Research Database (Denmark)

    Valentiner-Branth, Palle; Rasmussen, Jeppe N; Andersen, Peter H S;

    2013-01-01

    A seven-valent pneumococcal conjugate vaccine (PCV7) was introduced in the Danish childhood immunization program (2+1 schedule) in October 2007, followed by PCV13 starting from April 2010. The nationwide incidence of IPD among children younger than 5 years nearly halved after the introduction...... of children suspected to present with a vaccine failure. The period between April 19 and December 31, 2010 was considered a PCV7/PCV13 transitional period, where both vaccines were offered. We identified 45 episodes of IPD caused by a PCV7 serotype (23% of the total number) and 105 (55%) caused by one...... of the 6 additional serotypes in PCV13. Ten children had received at least one PCV7 dose before the onset of IPD caused by a PCV7 serotype. Seven children were considered to be incompletely vaccinated before IPD, but only three cases fulfilled the criteria of vaccine failure (caused by serotypes 14, 19F...

  8. Toll-Like Receptor 9 Enhances Bacterial Clearance and Limits Lung Consolidation in Murine Pneumonia Caused by Methicillin-Resistant Staphylococcus aureus

    Science.gov (United States)

    van der Meer, Anne Jan; Achouiti, Achmed; van der Ende, Arie; Soussan, Aicha Ait; Florquin, Sandrine; de Vos, Alex; Zeerleder, Sacha S; van der Poll, Tom

    2016-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is an important pathogen in pneumonia associated with severe lung damage. Tissue injury causes release of damage-associated molecular patterns (DAMPs), which may perpetuate inflammation. DNA has been implicated as a DAMP that activates inflammation through Toll-like receptor 9 (TLR9). The aim of this study was to evaluate the role of TLR9 in MRSA pneumonia. Wild-type (Wt) and TLR9 knockout (tlr9−/−) mice were infected intranasally with MRSA USA300 (BK 11540) (5E7 CFU) and euthanized at 6, 24, 48 or 72 h for analyses. MRSA pneumonia was associated with profound release of cell-free host DNA in the airways, as reflected by increases in nucleosome and DNA levels in bronchoalveolar lavage fluid (BALF), accompanied by transient detection of pathogen DNA in MRSA-free BALF supernatants. In BALF, as compared with Wt mice, tlr9−/− mice showed reduced tumor necrosis factor α and IL-6 levels at 6 h and reduced bacterial clearance at 6 and 24 h postinfection. Furthermore, tlr9−/− mice exhibited a greater influx of neutrophils in BALF and increased lung consolidation at 24 and 48 h. This study demonstrates the release of host- and pathogen-derived TLR9 ligands (DNA) into the alveolar space after infection with MRSA via the airways and suggests that TLR9 has proinflammatory effects during MRSA pneumonia associated with enhanced bacterial clearance and limitation of lung consolidation. PMID:27508882

  9. Thoracic Spondylodiscitis Caused by Methicillin-resistant Staphylococcus aureus as a Superinfection of Pulmonary Tuberculous Granuloma in an Immunocompetent Patient: A Case Report.

    Science.gov (United States)

    Donnarumma, Pasquale; Tarantino, Roberto; Palmarini, Valeria; De Giacomo, Tiziano; Delfini, Roberto

    2015-04-01

    Study Design Case report. Objective To describe a very rare case of an immunocompetent man who underwent surgery for thoracic spondylodiscitis caused by methicillin-resistant Staphylococcus aureus (MRSA) that developed as a superinfection of a pulmonary tuberculous granuloma. Methods Posterior decompression and pedicle screw vertebral fixation were followed by T5-T6 anterior somatotomy with implant of an expandable mesh and lateral plating as symptoms worsened. During the anterior approach, an atypical resection of the left lower lobe was also performed. Results A tuberculous granuloma was detected on histology. Ziehl-Neelsen stain confirmed the diagnosis. Culture also detected MRSA. Conclusions Early medical management is the first choice for spondylodiscitis to eradicate the infection and alleviate pain. Immobilization of the affected spine segments can protect the patient from vertebral collapse and from the appearance of neurologic deficits. Surgery is suggested if there are compressive effects on the spinal cord, spinal epidural abscess, vertebral collapse, and deformity. We decided to remove the abscess and to restore the anterior column using an anterior approach. Moreover, in this case, an anterior approach allowed us to identify the etiology of the lesion and to determine the best chemotherapy regimen.

  10. Pediatric invasive pneumococcal disease caused by vaccine serotypes following the introduction of conjugate vaccination in Denmark.

    Directory of Open Access Journals (Sweden)

    Zitta B Harboe

    Full Text Available A seven-valent pneumococcal conjugate vaccine (PCV7 was introduced in the Danish childhood immunization program (2+1 schedule in October 2007, followed by PCV13 starting from April 2010. The nationwide incidence of IPD among children younger than 5 years nearly halved after the introduction of PCV7 in the program, mainly due to a decline in IPD caused by PCV7-serotypes. We report the results from a nationwide population-based cohort study of laboratory confirmed IPD cases in children younger than 5 years during October 1, 2007 to December 31, 2010 and describe the characteristics of children suspected to present with a vaccine failure. The period between April 19 and December 31, 2010 was considered a PCV7/PCV13 transitional period, where both vaccines were offered. We identified 45 episodes of IPD caused by a PCV7 serotype (23% of the total number and 105 (55% caused by one of the 6 additional serotypes in PCV13. Ten children had received at least one PCV7 dose before the onset of IPD caused by a PCV7 serotype. Seven children were considered to be incompletely vaccinated before IPD, but only three cases fulfilled the criteria of vaccine failure (caused by serotypes 14, 19F and 23F. One case of vaccine failure was observed in a severely immunosuppressed child following three PCV7 doses, and two cases were observed in immunocompetent children following two infant doses before they were eligible for their booster. None of the IPD cases caused by the additional PCV13 serotypes had been vaccinated by PCV13 and there were therefore no PCV13-vaccine failures in the first 8-months after PCV13 introduction in Denmark.

  11. 金黄色葡萄球菌血流感染的临床特征分析%Clinical features of bloodstream infection caused by staphylococcus aureus

    Institute of Scientific and Technical Information of China (English)

    路明; 姚婉贞; 王筱宏; 刘振英

    2011-01-01

    OBJECTIVE To study the clinical characteristics and antimicrobial resistance of bloodstream infections caused by Staphylococcus aureus (SAU). METHODS Patients with bloodstream infections of SAU in our hospital from 2004 to 2008 were retrospectively reviewed. RESULTS All 28 patients had fever and 60. 7% with rigor. 18 cases had metastatic infection and lung was the most common metastasizing site. 85.7% of the patients had variety of vulnerable factors. 39% complicated by septic shock and the total mortality rate was 32.0%. 6 episodes were community acquired and 50. 0% of the primary infection site were from skin or soft tissues. All the six community-acquired SAU isolates were methicillin sensitive S. aureus (MSSA). The other 22 episodes were nosocomial infections, 45. 5% were related with central venous catheters, and 72. 0% of the SAU isolates were methicillin resistant S. aureus (MRSA). All the SAU isolates acquired from community and hospital were resistant to penicillin. CONCLUSION High fever with rigor and metastatic infection are common features of SAU bloodstream infection. MRSA isolates increased gradually with high mortality rate.%目的 了解金黄色葡萄球菌血流感染的临床特征及细菌耐药情况.方法 回顾分析医院2004-2008年由金黄色葡萄球菌所致血流感染患者的临床和微生物学资料.结果 共28例患者入选,均有发热,60.7%伴寒颤,18例有迁徙灶,肺受累最常见;85.7%的患者存在易感因素,39.0%合并感染性休克,死亡率32.0%;社区感染6例,多以皮肤为原发感染灶(50.0%),均为甲氧西林敏感金黄色葡萄球菌;医院内感染22例,多与中心静脉导管相关(45.5%),72.0%为耐甲氧西林金黄色葡萄球菌(MRSA);社区和医院内感染金黄色葡萄球菌株对青霉素100.0%耐药.结论 金黄色葡萄球菌血流感染多有高热、寒颤伴有迁徙灶,MRSA逐渐增多,导致很高的死亡率.

  12. Comparison of genomic and antimicrobial resistance features of latex agglutination test-positive and latex agglutination test-negative Staphylococcus aureus isolates causing bovine mastitis

    OpenAIRE

    Moser, A.; Stephan, R.; Corti, S; Johler, S.

    2013-01-01

    The dairy industry suffers massive economic losses due to staphylococcal mastitis in cattle. The Staphaureux latex agglutination test (Oxoid, Basel, Switzerland) was reported to lead to negative results in 54% of bovine Staphylococcus aureus strains, and latex-negative strains are thought to be less virulent than Staphaurex latex-positive strains. However, comparative information on virulence and resistance profiles of these 2 groups of Staph. aureus is scarce. Our objective was to associate ...

  13. Destruction of the hepatocyte junction by intercellular invasion of Leptospira causes jaundice in a hamster model of Weil's disease.

    Science.gov (United States)

    Miyahara, Satoshi; Saito, Mitsumasa; Kanemaru, Takaaki; Villanueva, Sharon Y A M; Gloriani, Nina G; Yoshida, Shin-ichi

    2014-08-01

    Weil's disease, the most severe form of leptospirosis, is characterized by jaundice, haemorrhage and renal failure. The mechanisms of jaundice caused by pathogenic Leptospira remain unclear. We therefore aimed to elucidate the mechanisms by integrating histopathological changes with serum biochemical abnormalities during the development of jaundice in a hamster model of Weil's disease. In this work, we obtained three-dimensional images of infected hamster livers using scanning electron microscope together with freeze-cracking and cross-cutting methods for sample preparation. The images displayed the corkscrew-shaped bacteria, which infiltrated the Disse's space, migrated between hepatocytes, detached the intercellular junctions and disrupted the bile canaliculi. Destruction of bile canaliculi coincided with the elevation of conjugated bilirubin, aspartate transaminase and alkaline phosphatase levels in serum, whereas serum alanine transaminase and γ-glutamyl transpeptidase levels increased slightly, but not significantly. We also found in ex vivo experiments that pathogenic, but not non-pathogenic leptospires, tend to adhere to the perijunctional region of hepatocyte couplets isolated from hamsters and initiate invasion of the intercellular junction within 1 h after co-incubation. Our results suggest that pathogenic leptospires invade the intercellular junctions of host hepatocytes, and this invasion contributes in the disruption of the junction. Subsequently, bile leaks from bile canaliculi and jaundice occurs immediately. Our findings revealed not only a novel pathogenicity of leptospires, but also a novel mechanism of jaundice induced by bacterial infection. PMID:24945433

  14. Examination of hospital length of stay in Canada among patients with acute bacterial skin and skin structure infection caused by methicillin-resistant Staphylococcus aureus

    Science.gov (United States)

    Potashman, Michele H; Stokes, Michael; Liu, Jieruo; Lawrence, Robin; Harris, Linda

    2016-01-01

    Purpose Skin infections, particularly those caused by resistant pathogens, represent a clinical burden. Hospitalization associated with acute bacterial skin and skin structure infections (ABSSSI) caused by methicillin-resistant Staphylococcus aureus (MRSA) is a major contributor to the economic burden of the disease. This study was conducted to provide current, real-world data on hospitalization patterns for patients with ABSSSI caused by MRSA across multiple geographic regions in Canada. Patients and methods This retrospective cohort study evaluated length of stay (LOS) for hospitalized patients with ABSSSI due to MRSA diagnosis across four Canadian geographic regions using the Discharge Abstract Database. Patients with ICD-10-CA diagnosis consistent with ABSSSI caused by MRSA between January 2008 and December 2014 were selected and assigned a primary or secondary diagnosis based on a prespecified ICD-10-CA code algorithm. Results Among 6,719 patients, 3,273 (48.7%) and 3,446 (51.3%) had a primary and secondary diagnosis, respectively. Among patients with a primary or secondary diagnosis, the cellulitis/erysipelas subtype was most common. The majority of patients presented with 0 or 1 comorbid condition; the most common comorbidity was diabetes. The mean LOS over the study period varied by geographic region and year; in 2014 (the most recent year analyzed), LOS ranged from 7.7 days in Ontario to 13.4 days in the Canadian Prairie for a primary diagnosis and from 18.2 days in Ontario to 25.2 days in Atlantic Canada for a secondary diagnosis. A secondary diagnosis was associated with higher rates of continuing care compared with a primary diagnosis (10.6%–24.2% vs 4.6%–12.1%). Conclusion This study demonstrated that the mean LOS associated with ABSSSI due to MRSA in Canada was minimally 7 days. Clinical management strategies, including medication management, which might facilitate hospital discharge, have the potential to reduce hospital LOS and related economic

  15. Invasive Streptococcus pneumoniae infection causing hemolytic uremic syndrome in children: Two recent cases

    OpenAIRE

    Vanderkooi, Otto G; Kellner, James D; Wade, Andrew W.; Jadavji, Tajdin; Midgley, Julian P; Louie, Thomas; Tyrrell, Gregory J.

    2003-01-01

    INTRODUCTION: Streptococcus pneumoniae is an uncommon cause of hemolytic uremic syndrome (HUS) with a unique pathophysiology that differs from Shiga toxin-related HUS.METHODS: Case descriptions for each patient are provided. Each strain of S pneumoniae was subjected to a pulsed-field gel electrophoresis (PFGE) analysis, Shiga toxin assay and polymerase chain reaction to detect Shiga toxin genes. A review of the current literature was conducted.CASE PRESENTATIONS: Two patients with S pneumonia...

  16. Unique cell adhesion and invasion properties of Yersinia enterocolitica O:3, the most frequent cause of human Yersiniosis.

    Directory of Open Access Journals (Sweden)

    Frank Uliczka

    2011-07-01

    Full Text Available Many enteric pathogens are equipped with multiple cell adhesion factors which are important for host tissue colonization and virulence. Y. enterocolitica, a common food-borne pathogen with invasive properties, uses the surface proteins invasin and YadA for host cell binding and entry. In this study, we demonstrate unique cell adhesion and invasion properties of Y. enterocolitica serotype O:3 strains, the most frequent cause of human yersiniosis, and show that these differences are mainly attributable to variations affecting the function and expression of invasin in response to temperature. In contrast to other enteric Yersinia strains, invasin production in O:3 strains is constitutive and largely enhanced compared to other Y. enterocolitica serotypes, in which invA expression is temperature-regulated and significantly reduced at 37°C. Increase of invasin levels is caused by (i an IS1667 insertion into the invA promoter region, which includes an additional promoter and RovA and H-NS binding sites, and (ii a P98S substitution in the invA activator protein RovA rendering the regulator less susceptible to proteolysis. Both variations were shown to influence bacterial colonization in a murine infection model. Furthermore, we found that co-expression of YadA and down-regulation of the O-antigen at 37°C is required to allow efficient internalization by the InvA protein. We conclude that even small variations in the expression of virulence factors can provoke a major difference in the virulence properties of closely related pathogens which may confer better survival or a higher pathogenic potential in a certain host or host environment.

  17. Unique cell adhesion and invasion properties of Yersinia enterocolitica O:3, the most frequent cause of human Yersiniosis.

    Science.gov (United States)

    Uliczka, Frank; Pisano, Fabio; Schaake, Julia; Stolz, Tatjana; Rohde, Manfred; Fruth, Angelika; Strauch, Eckhard; Skurnik, Mikael; Batzilla, Julia; Rakin, Alexander; Heesemann, Jürgen; Dersch, Petra

    2011-07-01

    Many enteric pathogens are equipped with multiple cell adhesion factors which are important for host tissue colonization and virulence. Y. enterocolitica, a common food-borne pathogen with invasive properties, uses the surface proteins invasin and YadA for host cell binding and entry. In this study, we demonstrate unique cell adhesion and invasion properties of Y. enterocolitica serotype O:3 strains, the most frequent cause of human yersiniosis, and show that these differences are mainly attributable to variations affecting the function and expression of invasin in response to temperature. In contrast to other enteric Yersinia strains, invasin production in O:3 strains is constitutive and largely enhanced compared to other Y. enterocolitica serotypes, in which invA expression is temperature-regulated and significantly reduced at 37°C. Increase of invasin levels is caused by (i) an IS1667 insertion into the invA promoter region, which includes an additional promoter and RovA and H-NS binding sites, and (ii) a P98S substitution in the invA activator protein RovA rendering the regulator less susceptible to proteolysis. Both variations were shown to influence bacterial colonization in a murine infection model. Furthermore, we found that co-expression of YadA and down-regulation of the O-antigen at 37°C is required to allow efficient internalization by the InvA protein. We conclude that even small variations in the expression of virulence factors can provoke a major difference in the virulence properties of closely related pathogens which may confer better survival or a higher pathogenic potential in a certain host or host environment.

  18. Glycoproteins and Gal-GalNAc cause Cryptosporidium to switch from an invasive sporozoite to a replicative trophozoite.

    Science.gov (United States)

    Edwinson, Adam; Widmer, Giovanni; McEvoy, John

    2016-01-01

    The apicomplexan parasite Cryptosporidium causes cryptosporidiosis, a diarrheal disease that can become chronic and life threatening in immunocompromised and malnourished people. There is no effective drug treatment for those most at risk of severe cryptosporidiosis. The disease pathology is due to a repeated cycle of host cell invasion and parasite replication that amplifies parasite numbers and destroys the intestinal epithelium. This study aimed to better understand the Cryptosporidium replication cycle by identifying molecules that trigger the switch from invasive sporozoite to replicative trophozoite. Our approach was to treat sporozoites of Cryptosporidium parvum and Cryptosporidium hominis, the species causing most human cryptosporidiosis, with various media under axenic conditions and examine the parasites for rounding and nuclear division as markers of trophozoite development and replication, respectively. FBS had a concentration-dependent effect on trophozoite development in both species. Trophozoite development in C. parvum, but not C. hominis, was enhanced when RPMI supplemented with 10% FBS (RPMI-FBS) was conditioned by HCT-8 cells for 3h. The effect of non-conditioned and HCT-8 conditioned RPMI-FBS on trophozoite development was abrogated by proteinase K and sodium metaperiodate pretreatment, indicating a glycoprotein trigger. Cryptosporidium parvum and C. hominis trophozoite development also was triggered by Gal-GalNAc in a concentration-dependent manner. Cryptosporidium parvum replication was greatest following treatments with Gal-GalNAc, followed by conditioned RPMI-FBS and non-conditioned RPMI-FBS (Pparvum for all treatments (P<0.05), and was greatest at the highest tested concentration of Gal-GalNAc (1mM). PMID:26432292

  19. Serotypes and Clonal Diversity of Streptococcus pneumoniae Causing Invasive Disease in the Era of PCV13 in Catalonia, Spain.

    Directory of Open Access Journals (Sweden)

    Eva Del Amo

    Full Text Available The aim of this study was to study the serotypes and clonal diversity of pneumococci causing invasive pneumococcal disease in Catalonia, Spain, in the era of 13-valent pneumococcal conjugate vaccine (PCV13. In our region, this vaccine is only available in the private market and it is estimated a PCV13 vaccine coverage around 55% in children. A total of 1551 pneumococcal invasive isolates received between 2010 and 2013 in the Molecular Microbiology Department at Hospital Sant Joan de Déu, Barcelona, were included. Fifty-two serotypes and 249 clonal types-defined by MLST-were identified. The most common serotypes were serotype 1 (n = 182; 11.7%, 3 (n = 145; 9.3%, 19A (n = 137; 8.8% and 7F (n = 122; 7.9%. Serotype 14 was the third most frequent serotype in children < 2 years (15 of 159 isolates. PCV7 serotypes maintained their proportion along the period of study, 16.6% in 2010 to 13.4% in 2013, whereas there was a significant proportional decrease in PCV13 serotypes, 65.3% in 2010 to 48.9% in 2013 (p<0.01. This decrease was mainly attributable to serotypes 19A and 7F. Serotype 12F achieved the third position in 2013 (n = 22, 6.4%. The most frequent clonal types found were ST306 (n = 154, 9.9%, ST191 (n = 111, 7.2%, ST989 (n = 85, 5.5% and ST180 (n = 80, 5.2%. Despite their decrease, PCV13 serotypes continue to be a major cause of disease in Spain. These results emphasize the need for complete PCV13 vaccination.

  20. Serotypes and patterns of antibiotic resistance in strains causing invasive pneumococcal disease in children less than 5 years of age.

    Directory of Open Access Journals (Sweden)

    Chunfeng Liu

    Full Text Available OBJECTIVE: The serotypes and patterns of antibiotic resistance of Streptococcus pneumoniae (S. pneumoniae strains that cause invasive pneumococcal disease (IPD in infants were analyzed to provide guidance for clinical disease prevention and treatment. METHODS: The clinical features of confirmed IPD were evaluated in 61 patients, less than 5 years of age, who were admitted to our hospital between January 2009 and December 2011. The serotypes and antibiotic resistance of strains of S.pneumoniae were determined using the capsular swelling method and the E-test. RESULTS: A total of 61 invasive strains were isolated. The serotype distribution of those isolates were 19A (41.0%, 14 (19.7%, 19F (11.5%, 23F (9.8%, 8 (4.9%, 9V (4.9%, 1 (3.3%, and 4, 6B, and 20 (each 1.6%. The percentage of S. pneumoniae strains resistant to erythromycin, clindamycin, and cotrimoxazole were 100%, 86.9%, and 100%, respectively. The percentage of S. pneumoniae strains resistant to penicillin, amoxicillin/clavulanic acid, cefuroxime, ceftriaxone, cefotaxime, cefepime, and meropenem were 42.6%, 18.0%, 82.0%, 18.0%, 13.1%, 13.1%, and 36.1%, respectively. The percentage of multidrug-resistant strains was 95.6%. Strains of all serotypes isolated in this study were highly resistant to erythromycin, cotrimoxazole, and clindamycin. Strains with serotype 19A had the highest rates of resistance. CONCLUSIONS: Serotype 19A strains were most frequently isolated from children with IPD treated in our hospital. The strains causing IPD are highly resistant to antibiotics.

  1. An unusual gangrenous goat mastitis caused by Staphylococcus aureus, Clostridium perfringens and Escherichia coli co-infection Mastite gangrenosa caprina atípica causada por co-infecção por Staphylococcus aureus, Clostridium perfringens e Escherichia coli

    Directory of Open Access Journals (Sweden)

    M.G. Ribeiro

    2007-06-01

    Full Text Available Relata-se, pela primeira vez no Brasil, a ocorrência de mastite gangrenosa caprina atípica causada pela co-infecção por Staphylococcus aureus, Clostridium perfringens e Escherichia coli em uma cabra da raça Boer, na segunda semana de lactação. Descrevem-se os achados clínicos, os procedimentos de diagnóstico microbiológico e a conduta terapêutica.

  2. An unusual gangrenous goat mastitis caused by Staphylococcus aureus, Clostridium perfringens and Escherichia coli co-infection Mastite gangrenosa caprina atípica causada por co-infecção por Staphylococcus aureus, Clostridium perfringens e Escherichia coli

    OpenAIRE

    M.G. Ribeiro; G.H.B. Lara; S.D. Bicudo; A.V.G. Souza; T. Salerno; A.K. Siqueira; J.S. Geraldo

    2007-01-01

    Relata-se, pela primeira vez no Brasil, a ocorrência de mastite gangrenosa caprina atípica causada pela co-infecção por Staphylococcus aureus, Clostridium perfringens e Escherichia coli em uma cabra da raça Boer, na segunda semana de lactação. Descrevem-se os achados clínicos, os procedimentos de diagnóstico microbiológico e a conduta terapêutica.

  3. Review on Panton Valentine leukocidin toxin carriage among Staphylococcus aureus.

    Science.gov (United States)

    Shrestha, B

    2013-09-01

    Panton Valentine leukocidin is a toxin making pores in the polymorphonuclear cells which is a virulence factor of some strains of Staphylococcus aureus. Initially it was produced by methicillin susceptible Staphylococcus aureus only. Later with the acquisition of mecA gene has lead it to be PVL positive methicillin resistant Staphylococcus aureus. Since MRSA are resistant to many antibiotics and further they produce a toxin the infections by PVL positive MRSA has become a challenge. PVL positive MRSA a virulent strain of drug resistant superbug MRSA that has spread around the world, has claimed many lives in UK, Europe, USA and Australia. Some strains of superbug attack the healthy young people and kill within 24 hrs. PVL positive Staphylococcus aureus has been reported to be associated with skin and soft tissue infections however they also cause invasive infections and necrotizing pneumonia. These microorganisms known to be community associated have spread to hospitals. Hospital acquired infection by such microorganisms lead to an increase in mortality hence should be controlled before they become prevalent in hospitals. PMID:24908537

  4. Whole-Genome Sequence of Staphylococcus aureus Strain LCT-SA112

    OpenAIRE

    Wang, Junfeng; Liu, Yanhong; Wan, Daiwei; Fang, Xiangqun; Li, Tianzhi; Guo, Yinghua; Chang, De; Su, Longxiang; Wang, Yajuan; Zhao, Jiao; Liu, Changting

    2012-01-01

    Staphylococcus aureus is a facultative anaerobic Gram-positive coccal bacterium. S. aureus is the most common species of Staphylococcus to cause staphylococcal infections, which are very common in clinical medicine. Here we report the genome sequence of S. aureus strain LCT-SA112, which was isolated from S. aureus subsp. aureus CGMCC 1.230.

  5. Molecular epidemiology of methicillin-resistant Staphylococcus aureus in Switzerland: sampling only invasive isolates does not allow a representative description of the local diversity of clones.

    Science.gov (United States)

    Senn, L; Basset, P; Greub, G; Prod'hom, G; Frei, R; Zbinden, R; Gaia, V; Balmelli, C; Pfyffer, G E; Mühlemann, K; Zanetti, G; Blanc, D S

    2013-07-01

    We conducted a molecular study of MRSA isolated in Swiss hospitals, including the first five consecutive isolates recovered from blood cultures and the first ten isolates recovered from other sites in newly identified carriers. Among 73 MRSA isolates, 44 different double locus sequence typing (DLST) types and 32 spa types were observed. Most isolates belonged to the NewYork/Japan, the UK-EMRSA-15, the South German and the Berlin clones. In a country with a low to moderate MRSA incidence, inclusion of non-invasive isolates allowed a more accurate description of the diversity. PMID:23458418

  6. The Staphylococcus aureus “superbug”

    OpenAIRE

    FOSTER, TIMOTHY JAMES

    2004-01-01

    PUBLISHED There has been some debate about the disease-invoking potential of Staphylococcus aureus strains and whether invasive disease is associated with particularly virulent genotypes, or "superbugs." A study in this issue of the JCI describes the genotyping of a large collection of nonclinical, commensal S. aureus strains from healthy individuals in a Dutch population. Extensive study of their genetic relatedness by amplified restriction fragment typing and comparison with strains that...

  7. Current status of Staphylococcus aureus causing neonatal nosocomial infection and analysis of drug resistance%新生儿医院感染金黄色葡萄球菌的现状及耐药性分析

    Institute of Scientific and Technical Information of China (English)

    孙卫

    2011-01-01

    OBJECTIVE To investigate the neonatal hospital infection in our hospital, and the drug resistance of Staphylococcus aureus causing neonatal infection. METHODS In our hospital from Jan 2007 to Dec 2010 neonatal nosocomial infection in children with 138 cases of clinical data were analyzed retrospectively, and the pathogenic bacteria and drug sensitivity testing were performed for statistical analysis, analysis of the infection and drug resistance were performed. RESULTS Investigation of strain 118 lines, the number of drug sensitive test showed that detection of S. Aureus isolates from 61, occupy 51. 7%, neonatal nosocomial infection pathogen was S. Aureus, all for baby room of hospital infection caused by strains. The genus Staphylococcus to penicillin and norfloxacin was most sensitive and resistant to most severe for cotrimoxazole; followed by cephalexin, cefazolin. S. Aureus causes of neonatal nosocomial infection rate showed ascendant trend. CONCLUSION S. Aureus is a leading cause of neonatal nosocomial infection risk factors, main and clinical antibiotic abuse related, according to the disease, pathogenic bacteria and drug sensitivity results of rational use of drugs, can slow down the growth of bacterial drug resistance.%目的 调查新生儿医院感染情况并对金黄色葡萄球菌致新生儿感染的耐药性进行分析.方法 对医院2007年1月-2010年12月180例新生儿医院感染临床资料进行回顾性分析,并对病原菌及药敏结果进行统计,分析其感染及耐药性.结果 调查病原菌180株,检出金黄色葡萄球菌61株,占33.9%,新生儿医院感染的病原菌主要为金黄色葡萄球菌;金黄色葡萄球菌对青霉素和诺氟沙星最为敏感,耐药最严重的为磺胺甲噁唑/甲氧苄啶;其次为头孢氨苄、头孢唑林.结论 金黄色葡萄球菌是导致新生儿医院感染的主要病原菌,其与临床滥用抗菌药物有关,根据病情、病原菌及药敏结果合理选用抗菌药物,

  8. Divergent responses of different endothelial cell types to infection with Candida albicans and Staphylococcus aureus.

    Directory of Open Access Journals (Sweden)

    Kati Seidl

    Full Text Available Endothelial cells are important in the pathogenesis of bloodstream infections caused by Candida albicans and Staphylococcus aureus. Numerous investigations have used human umbilical vein endothelial cells (HUVECs to study microbial-endothelial cell interactions in vitro. However, the use of HUVECs requires a constant supply of umbilical cords, and there are significant donor-to-donor variations in these endothelial cells. The use of an immortalized endothelial cell line would obviate such difficulties. One candidate in this regard is HMEC-1, an immortalized human dermal microvascular endothelial cell line. To determine if HMEC-1 cells are suitable for studying the interactions of C. albicans and S. aureus with endothelial cells in vitro, we compared the interactions of these organisms with HMEC-1 cells and HUVECs. We found that wild-type C. albicans had significantly reduced adherence to and invasion of HMEC-1 cells as compared to HUVECs. Although wild-type S. aureus adhered to and invaded HMEC-1 cells similarly to HUVECs, an agr mutant strain had significantly reduced invasion of HMEC-1 cells, but not HUVECs. Furthermore, HMEC-1 cells were less susceptible to damage induced by C. albicans, but more susceptible to damage caused by S. aureus. In addition, HMEC-1 cells secreted very little IL-8 in response to infection with either organism, whereas infection of HUVECs induced substantial IL-8 secretion. This weak IL-8 response was likely due to the anatomic site from which HMEC-1 cells were obtained because infection of primary human dermal microvascular endothelial cells with C. albicans and S. aureus also induced little increase in IL-8 production above basal levels. Thus, C. albicans and S. aureus interact with HMEC-1 cells in a substantially different manner than with HUVECs, and data obtained with one type of endothelial cell cannot necessarily be extrapolated to other types.

  9. A pig model of acute Staphylococcus aureus induced pyemia

    DEFF Research Database (Denmark)

    Nielsen, O. L.; Iburg, T.; Aalbæk, B.;

    2009-01-01

    Background: Sepsis caused by Staphylococcus aureus constitutes an important cause of morbidity and mortality in humans, and the incidence of this disease-entity is increasing. In this paper we describe the initial microbial dynamics and lesions in pigs experimentally infected with S. aureus....... aureus isolated from man and an extension of the timeframe aiming at inducing sepsis, severe sepsis and septic shock....

  10. Investigation of resistant genes and encoding genes of capsular antigens in invasive Staphylococcus aureus%侵袭性感染金黄色葡萄球菌耐药基因与荚膜抗原基因研究

    Institute of Scientific and Technical Information of China (English)

    唐朝贵; 林涛; 陈滢; 李前辉; 张小云

    2016-01-01

    目的:调查金黄色葡萄球菌的耐药基因与荚膜抗原基因携带情况及毒力基因的亲缘性,为临床治疗提供参考依据。方法收集医院住院患者无菌部位体液分离出的金黄色葡萄球菌共15株,以金黄色葡萄球菌的 nuc看家基因PCR检测阳性判定为金黄色葡萄球菌,结合金黄色葡萄球菌的细胞毒素与侵袭毒素基因检测结果作样本聚类分析,数据采用SPSS 17.0软件进行统计分析。结果15株金黄色葡萄球菌共检出β‐内酰胺类耐药基因mecA 8株,阳性率为53.3%,氨基糖苷类耐药基因 aac(6′)/ap h(2″)5株,阳性率为33.3%、ap h(3′)‐Ⅲ2株,阳性率为13.3%,大环内酯类耐药基因ermB 2株,阳性率为13.3%;季胺类消毒剂耐药基因 qacA 2株,阳性率为13.3%,荚膜抗原基因cap57株,cap85株,阳性率分别为46.7%、33.3%。结论15株金黄色葡萄球菌β‐内酰胺类、氨基糖苷类、大环内酯类耐药基因和耐药表型相符,但这组菌侵袭性感染的结局不佳比率高。%OBJECTIVE To investigate resistant genes and encoding genes of capsular antigens in a group of invasive Staphylococcus aureus so as to provide references for clinical treatment .METHODS Totally 15 strains of S .au‐reus were collected from inpatients in Huan′an First Hospital ,Jiangsu Province ,China .Then ,nuc was used to i‐dentify S .aureus .Furthermore ,beta‐lactamase gene mecA ,aminoglycosides resistance gene :aac(6′)/aph(2″) , aph(3′)‐Ⅲ ,ant(3″)‐Ⅰ ,ant(4′,4″) ,macrolide resistant gene :ermA ,ermB ,ermC ,quaternary disinfetant re‐sistant gene qacA ,and encoding genes of capsular antigens cap5 ,cap8 were analyzed by PCR .Finally ,sample cluster analysis was performed depending on these genes and encoding genes of adhesins ,cytotoxins and invasive toxins detected before .SPSS 17 .0 was explored to make statistical analysis .RESULTS A total

  11. Mild Staphylococcus aureus Skin Infection Improves the Course of Subsequent Endogenous S. aureus Bacteremia in Mice.

    Directory of Open Access Journals (Sweden)

    Sanne van den Berg

    Full Text Available Staphylococcus aureus carriers with S. aureus bacteremia may have a reduced mortality risk compared to non-carriers. A role for the immune system is suggested. Here, we study in mice the effect of mild S. aureus skin infection prior to endogenous or exogenous S. aureus bacteremia, and evaluate protection in relation to anti-staphylococcal antibody levels. Skin infections once or twice by a clinical S. aureus isolate (isolate P or S. aureus strain 8325-4 were induced in mice free of S. aureus and anti-staphylococcal antibodies. Five weeks later, immunoglobulin G (IgG levels in blood against 25 S. aureus antigens were determined, and LD50 or LD100 bacteremia caused by S. aureus isolate P was induced. S. aureus skin infections led to elevated levels of anti-staphylococcal IgG in blood. One skin infection improved the course of subsequent severe endogenous bacteremia only. A second skin infection further improved animal survival rate, which was associated with increased pre-bacteremia IgG levels against Efb, IsaA, LukD, LukE, Nuc, PrsA and WTA. In conclusion, S. aureus isolate P skin infection in mice reduces the severity of subsequent endogenous S. aureus bacteremia only. Although cellular immune effects cannot be rules out, anti-staphylococcal IgG against specified antigens may contribute to this effect.

  12. Clinical and epidemiological differences between septic arthritis of the knee and hip caused by oxacillin-sensitive and -resistant s. aureus

    Directory of Open Access Journals (Sweden)

    Camilo Partezani Helito

    2015-01-01

    Full Text Available OBJECTIVE: To establish the risk factors for joint infection by oxacillin-resistant Staphylococcus aureus (MRSA using clinical and epidemiological data. METHODS: All septic arthritis cases of the knee and hip diagnosed and treated in our institution from 2006 to 2012 were evaluated retrospectively. Only patients with cultures identified as microbial agents were included in the study. The clinical and epidemiological characteristics of the patients were analyzed, seeking the differences between populations affected by MRSA and oxacillin-sensitive Staphylococcus aureus (MSSA. RESULTS: S. aureus was isolated in thirty-five patients (46.0% in our total sample, 25 in the knee and 10 in the hip. Of these 35 patients, 22 presented with MSSA and 13 presented with MRSA. Provenance from a health service-related environment, as described by the Centers for Disease Control and Prevention, was the only variable associated with oxacillin-resistant strains of this bacterium (p = 0.001. CONCLUSION: Provenance from a health service-related environment was associated with a higher incidence of MRSA-related septic arthritis, suggesting that this agent should be considered in the initial choice of antibiotic treatment. Previous surgeries of the knee or affected limb and the absence of leukocytes might also be related to infection with this agent.

  13. Combination of silver nanoparticles and Drosera binata extract as a possible alternative for antibiotic treatment of burn wound infections caused by resistant Staphylococcus aureus.

    Science.gov (United States)

    Krychowiak, Marta; Grinholc, Mariusz; Banasiuk, Rafal; Krauze-Baranowska, Miroslawa; Głód, Daniel; Kawiak, Anna; Królicka, Aleksandra

    2014-01-01

    Staphylococcus aureus is the most common infectious agent involved in the development of skin infections that are associated with antibiotic resistance, such as burn wounds. As drug resistance is a growing problem it is essential to establish novel antimicrobials. Currently, antibiotic resistance in bacteria is successfully controlled by multi-drug therapies. Here we demonstrate that secondary metabolites present in the extract obtained from Drosera binata in vitro cultures are effective antibacterial agents against S. aureus grown in planktonic culture and in biofilm. Moreover, this is the first report demonstrating the synergistic interaction between the D. binata extract and silver nanoparticles (AgNPs), which results in the spectacular enhancement of the observed bactericidal activity, while having no cytotoxic effects on human keratinocytes. Simultaneous use of these two agents in significantly reduced quantities produces the same effect, i.e. by killing 99.9% of bacteria in inoculum or eradicating the staphylococcal biofilm, as higher amounts of the agents used individually. Our data indicates that combining AgNPs with either the D. binata extract or with its pure compound (3-chloroplumbagin) may provide a safe and highly effective alternative to commonly used antibiotics, which are ineffective towards the antibiotic-resistant S. aureus. PMID:25551660

  14. Combination of silver nanoparticles and Drosera binata extract as a possible alternative for antibiotic treatment of burn wound infections caused by resistant Staphylococcus aureus.

    Directory of Open Access Journals (Sweden)

    Marta Krychowiak

    Full Text Available Staphylococcus aureus is the most common infectious agent involved in the development of skin infections that are associated with antibiotic resistance, such as burn wounds. As drug resistance is a growing problem it is essential to establish novel antimicrobials. Currently, antibiotic resistance in bacteria is successfully controlled by multi-drug therapies. Here we demonstrate that secondary metabolites present in the extract obtained from Drosera binata in vitro cultures are effective antibacterial agents against S. aureus grown in planktonic culture and in biofilm. Moreover, this is the first report demonstrating the synergistic interaction between the D. binata extract and silver nanoparticles (AgNPs, which results in the spectacular enhancement of the observed bactericidal activity, while having no cytotoxic effects on human keratinocytes. Simultaneous use of these two agents in significantly reduced quantities produces the same effect, i.e. by killing 99.9% of bacteria in inoculum or eradicating the staphylococcal biofilm, as higher amounts of the agents used individually. Our data indicates that combining AgNPs with either the D. binata extract or with its pure compound (3-chloroplumbagin may provide a safe and highly effective alternative to commonly used antibiotics, which are ineffective towards the antibiotic-resistant S. aureus.

  15. Oak forest exploitation and black-locust invasion caused severe shifts in epiphytic lichen communities in Northern Italy.

    Science.gov (United States)

    Nascimbene, Juri; Marini, Lorenzo

    2010-10-15

    In the last two centuries, native European oak forests have undergone a dramatic decline related to increasing human pressure for agriculture and urbanization. Oak forests were either completely eradicated and transformed into agricultural landscapes or replaced by second-growth formations. Intensive forest management and the replacement of native forests with production forests or arable lands are recognized amongst the main threats to many lichens in Europe. In this study, we used historical information on the epiphytic lichen biota which was hosted in a native oak-dominated forest of Northern Italy to identify shifts of lichen communities due to the changes in land use which occurred during the last two centuries. We also compared the epiphytic lichen communities inhabiting remnant oak forests with those found in the habitats that have replaced native forests: black-locust forests and agrarian landscapes. Almost all the species sampled during the 19th century are now extinct. The loss of native habitat and the subsequent invasion by black locust were probably the most influential factors which affected the composition of lichen communities, causing the local extinction of most of the species historically recorded. Despite the fact that oak remnants host only a few species which were historically recorded, and that they currently are the lichen poorest habitat in the study region, they host lichen assemblages differing from those of black-locust forests and agrarian stands. In these habitats lichen assemblages are mainly composed of species adapted to well-lit, dry conditions and tolerating air pollution and eutrophication. This pattern is likely to be common also in other lowland and hilly regions throughout Northern Italy where oak forests are targeted among the habitats of conservation concern at the European level. For this reason, a national strategy for biodiversity conservation and monitoring of lowlands forests should provide the framework for local

  16. The cell surface proteome of Staphylococcus aureus

    NARCIS (Netherlands)

    Dreisbach, Annette; van Dijl, Jan Maarten; Buist, Girbe

    2011-01-01

    The Gram-positive bacterium Staphylococcus aureus is a wide spread opportunistic pathogen that can cause a range of life-threatening diseases. To obtain a better understanding of the global mechanisms for pathogenesis and to identify novel targets for therapeutic interventions, the S. aureus proteom

  17. Minimally Invasive Treatment of Biventricular Hydrocephalus Caused by a Giant Basilar Apex Aneurysm via a Staged Combination of Endoscopy and Endovascular Embolization: A Case Report.

    Science.gov (United States)

    Setty, Pradeep; Volkov, Andrey; Richards, Boyd; Barrett, Ryan

    2015-01-01

    Biventricular hydrocephalus caused by a Giant Basilar Apex Aneurysm (GBAA) is a rare finding that presents unique and challenging treatment decisions. We report a case of GBAA causing a life-threatening biventricular hydrocephalus in which both the aneurysm and hydrocephalus were given definitive treatment through a staged, minimally invasive approach. An obtunded 82-year-old male was found to have biventricular hydrocephalus caused by an unruptured GBAA obstructing the foramina of Monro. The patient was treated via staged, minimally invasive technique that first involved endoscopic fenestration of the septum pellucidum to create communication between the lateral ventricles. A programmable ventriculo-peritoneal shunt was then placed with a high-pressure setting. The patient was then loaded with dual anti-platelet therapy prior to undergoing endovascular coiling of the GBAA with adjacent stenting of the Posterior Cerebral Artery. He remained on dual anti-platelet therapy and the shunt setting was lowered at the bedside to treat the hydrocephalus. At 6-month follow up, the patient had returned to his cognitive baseline, speaking fluently and appropriately. Biventricular hydrocephalus caused by a GBAA can successfully be treated in a minimally invasive fashion utilizing a combination of endoscopy and endovascular therapy, even when a stent-assisted coiling is needed.

  18. Vaccination with a recombinant fragment of collagen adhesin provides protection against Staphylococcus aureus-mediated septic death.

    Science.gov (United States)

    Nilsson, I M; Patti, J M; Bremell, T; Höök, M; Tarkowski, A

    1998-06-15

    Staphylococcus aureus is a major cause of nosocomial and community-acquired infections. Morbidity and mortality due to infections such as sepsis, osteomyelitis, septic arthritis, and invasive endocarditis remain high despite the use of antibiotics. The emergence of antibiotic resistant super bugs mandates that alternative strategies for the prevention and treatment of S. aureus infections are developed. We investigated the ability of vaccination with a recombinant fragment of the S. aureus collagen adhesin to protect mice against sepsis-induced death. Actively immunized NMRI mice were intravenously inoculated with the S. aureus clinical isolate strain Phillips. 14 d after inoculation, mortality in the collagen adhesin-vaccinated group was only 13%, compared with 87% in the control antigen immunized group (P < 0.001). To determine if the protective effect was antibody mediated, we passively immunized naive mice with collagen adhesin-specific antibodies. Similar to the active immunization strategy, passive transfer of collagen adhesin-specific antibodies protected mice against sepsis-induced death. In vitro experiments indicated that S. aureus opsonized with sera from collagen adhesin immunized mice promoted phagocytic uptake and enhanced intracellular killing compared with bacteria opsonized with sera from control animals. These results indicate that the collagen adhesin is a viable target in the development of immunotherapeutics against S. aureus.

  19. Comparison of genomic and antimicrobial resistance features of latex agglutination test-positive and latex agglutination test-negative Staphylococcus aureus isolates causing bovine mastitis.

    Science.gov (United States)

    Moser, A; Stephan, R; Corti, S; Johler, S

    2013-01-01

    The dairy industry suffers massive economic losses due to staphylococcal mastitis in cattle. The Staphaureux latex agglutination test (Oxoid, Basel, Switzerland) was reported to lead to negative results in 54% of bovine Staphylococcus aureus strains, and latex-negative strains are thought to be less virulent than Staphaurex latex-positive strains. However, comparative information on virulence and resistance profiles of these 2 groups of Staph. aureus is scarce. Our objective was to associate the latex agglutination phenotype of Staph. aureus strains isolated from bovine mastitis milk with data on clonal complexes, virulence genes, and antibiotic resistance to (1) determine the virulence profiles of the Staphaureux test positive and Staphaurex test negative groups, and (2) provide data needed to improve treatment of bovine mastitis and to identify potential vaccine targets. Seventy-eight Staph. aureus strains isolated from 78 cows on 57 Swiss farms were characterized. Latex agglutination was tested by Staphaureux kit, and resistance profiles were generated by disk diffusion. A DNA microarray was used to assign clonal complexes (CC) and to determine virulence and resistance gene profiles. By the Staphaureux test, 49% of the isolates were latex-positive and 51% were latex-negative. All latex-negative strains were assigned to CC151, whereas latex-positive strains were assigned to various clonal complexes, including CC97 (n=16), CC8 (n=10), CC479 (n=5), CC20 (n=4), CC7 (n=1), CC9 (n=1), and CC45 (n=1). Although the latex-negative isolates were susceptible to all antimicrobial agents tested, 24% of latex-positive isolates were classified as intermediate with regard to cefalexin-kanamycin and 13% were resistant to both ampicillin and penicillin. Microarray profiles of latex-negative isolates were highly similar, but differed largely from those of latex-positive isolates. Although the latex-negative group lacked several enterotoxin genes and sak, it exhibited significantly

  20. Effects of vancomycin versus nafcillin in enhancing killing of methicillin-susceptible Staphylococcus aureus causing bacteremia by human cathelicidin LL-37.

    Science.gov (United States)

    Le, J; Dam, Q; Schweizer, M; Thienphrapa, W; Nizet, V; Sakoulas, G

    2016-09-01

    Recent studies have demonstrated that anti-staphylococcal beta-lactam antibiotics, like nafcillin, render methicillin-resistant Staphylococcus aureus (MRSA) more susceptible to killing by innate host defense peptides (HDPs), such as cathelicidin LL-37. We compared the effects of growth in 1/4 minimum inhibitory concentration (MIC) of nafcillin or vancomycin on the LL-37 killing of 92 methicillin-susceptible S. aureus (MSSA) isolates. For three randomly selected strains among these, we examined the effects of nafcillin, vancomycin, daptomycin, or linezolid on LL-37 killing and autolysis. Growth in the presence of subinhibitory nafcillin significantly enhanced LL-37 killing of MSSA compared to vancomycin and antibiotic-free controls. Nafcillin also reduced MSSA production of the golden staphylococcal pigment staphyloxanthin in 39 % of pigmented strains vs. 14 % for vancomycin. Among the antibiotics tested, only nafcillin resulted in significantly increased MSSA autolysis. These studies point to additional mechanisms of anti-staphylococcal activity of nafcillin beyond direct bactericidal activity, properties that vancomycin and other antibiotic classes do not exhibit. The ability of nafcillin to enhance sensitivity to innate HDPs may contribute to its superior effectiveness against MSSA, as suggested by studies comparing clinical outcomes to vancomycin treatment. PMID:27234592

  1. 医院感染金黄色葡萄球菌耐药表型与耐药基因研究%Drug resistance phenotypes and drug resistance genes in Staphylococcus aureus causing nosocomial infections

    Institute of Scientific and Technical Information of China (English)

    张志军; 曹海燕; 刘延媛; 刘春来

    2015-01-01

    OBJECTIVE To study the drug resistance phenotypes and drug resistance genes in Staphylococcus au‐reus causing nosocomial infections so as to provide guidance for clinical prevention and treatment of the nosocomial infections .METHODS From Jan 2011 to Jan 2013 ,totally 120 strains of S .aureus were isolated from the submitted specimens that were obtained from the patients with nosocomial infections .According to the standard operation procedures of clinical laboratory standard institute ,the drug resistance phenotypes and drug resistance genes in the S .aureus strains were analyzed by using polymerase‐chain‐reaction (PCR) .RESULTS The drug resistance rates of the S .aureus strains to penicillin ,erythromycin ,gentamicin ,clindamycin ,tetracycline ,and ciprofloxacin were 100 .00% ,98 .83% ,80 .00% ,76 .67% ,76 .67% ,and 75 .83% ,respectively ;the strains were highly susceptible to vancomycin and linezolid .Among the different drug resistance phenotypes of S .aureus ,the drug resistance rate of the type Ⅵ S .aureus was the highest (97 .50% ) , followed by the type Ⅴ (67 .50% ) and the type Ⅳ(60 .00% ) .Among the S .aureus strains harboring different drug resistance genes ,the drug resistance rate of the S .aureus strains harboring mecA was the highest (98 .83% ) ,and the drug resistance of the drug resistance genes in the S .aureus strains was in accordance with the drug resistance of the S .aureus strains .CONCLUSION The S .aureus strains causing nosocomial infections are highly resistant to most of the antibiotics and highly susceptible to vancomycin .The type Ⅵ ,type Ⅴ ,and type Ⅳ are the major drug resistance phenotypes;the tetK and mecA are the predominant drug resistance genes .%目的:研究医院感染耐药金黄色葡萄球菌的耐药表型及耐药基因,以期为临床防治医院感染提供参考。方法选取2011年1月-2013年1月医院感染患者送检标本中分离的120株金黄色葡萄球菌,根据美国临床实验

  2. Stress Responses in Staphylococcus aureus

    DEFF Research Database (Denmark)

    Frees, Dorte; Ingmer, Hanne

    2016-01-01

    Staphylococcus aures are prominent members of the normal flora of humans and animals, but are also a major cause of mild and severe infections. To persist and disseminate in the human host, and to survive in environmental settings, such as hospitals, S. aureus have developed a plethora of cellular...

  3. Recent emergence of Staphylococcus aureus clonal complex 398 in human blood cultures.

    Directory of Open Access Journals (Sweden)

    Erwin Verkade

    Full Text Available BACKGROUND: Recently, a clone of MRSA with clonal complex 398 (CC398 has emerged that is related to an extensive reservoir in animals, especially pigs and veal calves. It has been reported previously that methicillin-susceptible variants of CC398 circulate among humans at low frequency, and these have been isolated in a few cases of bloodstream infections (BSI. The purpose of this study was to determine the prevalence of S. aureus CC398 in blood cultures taken from patients in a geographic area with a high density of pigs. METHODOLOGY/PRINCIPAL FINDINGS: In total, 612 consecutive episodes of S. aureus BSI diagnosed before and during the emergence of CC398 were included. Three strains (2 MSSA and 1 MRSA that were isolated from bacteremic patients between 2010-2011 were positive in a CC398 specific PCR. There was a marked increase in prevalence of S. aureus CC398 BSI isolated between 2010-2011 compared to the combined collections that were isolated between 1996-1998 and 2002-2005 (3/157, 1.9% vs. 0/455, 0.0%; p = 0.017. CONCLUSIONS/SIGNIFICANCE: In conclusion, in an area with a relative high density of pigs, S. aureus CC398 was found as a cause of BSI in humans only recently. This indicates that S. aureus CC398 is able to cause invasive infections in humans and that the prevalence is rising. Careful monitoring of the evolution and epidemiology of S. aureus CC398 in animals and humans is therefore important.

  4. Enhanced Biofilm Formation and Increased Resistance to Antimicrobial Agents and Bacterial Invasion Are Caused by Synergistic Interactions in Multispecies Biofilms

    DEFF Research Database (Denmark)

    Burmølle, Mette; Webb, J.S.; Rao, D.;

    2006-01-01

    Most biofilms in their natural environments are likely to consist of consortia of species that influence each other in synergistic and antagonistic manners. However, few reports specifically address interactions within multispecies biofilms. In this study, 17 epiphytic bacterial strains, isolated...... specific interactions. In summary, our data strongly indicate that synergistic effects promote biofilm biomass and resistance of the biofilm to antimicrobial agents and bacterial invasion in multispecies biofilms.......Most biofilms in their natural environments are likely to consist of consortia of species that influence each other in synergistic and antagonistic manners. However, few reports specifically address interactions within multispecies biofilms. In this study, 17 epiphytic bacterial strains, isolated......-species biofilms resisted invasion to a greater extent than did the biofilms formed by the single species. Replacement of each strain by its cell-free culture supernatant suggested that synergy was dependent both on species-specific physical interactions between cells and on extracellular secreted factors or less...

  5. Massive Intrabile Duct Invasion Caused by a Fatal Progression of Colonic Adenocarcinoma: Abdominal Computed Tomography Findings and Cholangiography Correlation

    OpenAIRE

    Rodriguez-Pascual, Jesus; Abbitt, Michael Tyler B; Fernádez, Marisol; Camuñez, Fernando; Pérez-Rodríguez, Francisco José

    2016-01-01

    In this report, we present an unusual case of jaundice in a patient with advanced colorectal cancer due to intraductal tumour invasion of the intra- and extrahepatic biliary tree. This complication proved to be fatal despite aggressive therapeutic management. A correct diagnosis of this type of involvement was achieved by a combination of diagnostic and therapeutic cholangiography. Despite adequate biliary decompression, the patient died from liver failure and biliary sepsis.

  6. Genomic Analysis of Companion Rabbit Staphylococcus aureus.

    Science.gov (United States)

    Holmes, Mark A; Harrison, Ewan M; Fisher, Elizabeth A; Graham, Elizabeth M; Parkhill, Julian; Foster, Geoffrey; Paterson, Gavin K

    2016-01-01

    In addition to being an important human pathogen, Staphylococcus aureus is able to cause a variety of infections in numerous other host species. While the S. aureus strains causing infection in several of these hosts have been well characterised, this is not the case for companion rabbits (Oryctolagus cuniculus), where little data are available on S. aureus strains from this host. To address this deficiency we have performed antimicrobial susceptibility testing and genome sequencing on a collection of S. aureus isolates from companion rabbits. The findings show a diverse S. aureus population is able to cause infection in this host, and while antimicrobial resistance was uncommon, the isolates possess a range of known and putative virulence factors consistent with a diverse clinical presentation in companion rabbits including severe abscesses. We additionally show that companion rabbit isolates carry polymorphisms within dltB as described as underlying host-adaption of S. aureus to farmed rabbits. The availability of S. aureus genome sequences from companion rabbits provides an important aid to understanding the pathogenesis of disease in this host and in the clinical management and surveillance of these infections. PMID:26963381

  7. Staphylococcus aureus and Pregnancy

    Science.gov (United States)

    Staphylococcus aureus and Pregnancy In every pregnancy, a woman starts out with a 3-5% chance of ... risk. This sheet talks about whether exposure to staphylococcus aureus may increase the risk for birth defects ...

  8. The first report in Brazil of severe infection caused by community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA

    Directory of Open Access Journals (Sweden)

    R. Rozenbaum

    2009-08-01

    Full Text Available Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA is an emergent pathogen in Brazil. However, there are no data on the prevalence of CA-MRSA. We report here the first well-characterized case of severe life-threatening CA-MRSA infection in a child living in Rio de Janeiro city. The patient had many complications including hematogenous osteomyelitis and involvement of multiple sites requiring drainage of soft-tissue abscess, and pleural and pericardial empyema. The MRSA isolates recovered were genotyped using PFGE, SCCmec typing and multilocus sequence typing. Disk diffusion tests were performed following Clinical and Laboratory Standards Institute recommendations. In addition, the presence of Panton-Valentine leukocidin (PVL was assessed by PCR amplification, using specific primers for lukF-pv (encoding for the F subunit of the PVL. The bacterial isolates were related to the ST30-SCCmecIV lineage (Oceania Southwest Pacific clone, a PVL producer CA-MRSA previously detected in Porto Alegre, RS, Brazil. Also, the isolates analyzed were susceptible to all non-β-lactam antibiotics tested. The present report demonstrates that disseminated CA-MRSA disease is also occurring in Rio de Janeiro. Thus, the empirical treatment of moderate or severe infections suspected of being associated with CA-MRSA needs to be reviewed in order to allow prompt initiation of an effective therapy that also covers these microorganisms.

  9. 金黄色葡萄球菌性奶牛乳房炎研究的知识图谱分析%Knowledge Maps of Research on Bovine Mastitis Caused by Staphylococcus aureus

    Institute of Scientific and Technical Information of China (English)

    杨峰; 王玲; 王旭荣; 李新圃; 罗金印; 张世栋; 李宏胜

    2016-01-01

    Based on citespace Ⅲ,knowledge maps of countries,institutions,authors,cite journals,cite references,key words and year distributions of publications on research of bovine mastitis caused by Staphylococcus aureus are studied,which is conducted on 1 797 international scientific literatures down-loaded from Web of ScienceTM core collection (1 995-2015).The analyzed results showed,in research field of bovine mastitis caused by Staphylococcus aureus ,the number of published papers increased from 1 995-2012,but it began to decrease in 2013;countries and institutions involved in the research were mainly dis-tributed in America and Europe,and universities play important roles in this field.In addition,the re-search field are mainly focus on isolation and identification of pathogens,detection of drug susceptibility and pathogenesis exploration.And in future time,studies will pay more attention to research of Staphylo-coccus aureus biofilm.%基于 CitespaceⅢ研究了1995年-2015年 Web of ScienceTM 核心合集数据库所收录的金黄色葡萄球菌性奶牛乳房炎相关的1797条科技文献,分析了年度发文量,绘制了国家、机构、作者、被引期刊、被引文献及关键词的知识图谱。全世界金黄色葡萄球菌性奶牛乳房炎研究领域的发文量从1995年-2012年持续上升,2013年发文量开始呈下滑的趋势;研究金黄色葡萄球菌性奶牛乳房炎的国家和机构主要分布在美洲和欧洲,大学是该研究领域的主要研究机构;金黄色葡萄球菌性奶牛乳房炎的研究热点集中于病原菌的分离鉴定、药物敏感性检测和致病机理探究,该领域未来一段时间的研究方向将侧重于金黄色葡萄球菌生物被膜相关的研究。

  10. [Muco-cutaneous colonization and nosocomial infections caused by methicillin-resistant Staphylococcus aureus and Acinetobacter baumanii in intensive care patients].

    Science.gov (United States)

    Pasdeloup, T; Caron, F; Soyer, S; Castel, O; Aubenneau, C; Fauchere, J L; Robert, R

    2000-07-01

    This study was designed to assess the frequency and risk factors for colonization with MRSA and A. baumanii in the intensive care unit, and to analyse the relationship between colonization and infection with MRSA or A. baumanii. During a 24-day survey period, colonization was studied weekly with nasal, throat and digit skin swabs; nosocomial infections were routinely monitored according to CDC recommendations. Clinical data and invasive procedures were registered during a one-year non-epidemic period; 103 ICU patients hospitalized for more than 7 days were prospectively included. We investigated acquired colonization and nosocomial infection with SAMR or A. baumanii for 87 patients not colonized by SAMR or A. baumanii on admission. The colonization acquisition rate was 56% for MRSA and 27% for A. baumanii. Infection incidence (cases per 1,000 patient-days) was 6.46 for MRSA and 1.61 for A. baumanii. On univariate analysis, acquired MRSA colonization was associated with longer ICU stays, longer mechanical ventilation and longer central venous catheterization. Multivariate analysis only showed an association with longer ICU stay. Acquired A. baumanii colonization was associated with SAPSII, longer mechanical ventilation, and longer central venous catheterization in univariate analysis. Multivariate analysis only showed an association with SAPSII and longer mechanical ventilation. In this study, SAMR or A. baumanii infections were not associated with colonization or clinical setting or invasive procedures. PMID:10965530

  11. A non-coding RNA promotes bacterial persistence and decreases virulence by regulating a regulator in Staphylococcus aureus.

    Directory of Open Access Journals (Sweden)

    Cédric Romilly

    2014-03-01

    Full Text Available Staphylococcus aureus produces a high number of RNAs for which the functions are poorly understood. Several non-coding RNAs carry a C-rich sequence suggesting that they regulate mRNAs at the post-transcriptional level. We demonstrate that the Sigma B-dependent RsaA RNA represses the synthesis of the global transcriptional regulator MgrA by forming an imperfect duplex with the Shine and Dalgarno sequence and a loop-loop interaction within the coding region of the target mRNA. These two recognition sites are required for translation repression. Consequently, RsaA causes enhanced production of biofilm and a decreased synthesis of capsule formation in several strain backgrounds. These phenotypes led to a decreased protection of S. aureus against opsonophagocytic killing by polymorphonuclear leukocytes compared to the mutant strains lacking RsaA. Mice animal models showed that RsaA attenuates the severity of acute systemic infections and enhances chronic catheter infection. RsaA takes part in a regulatory network that contributes to the complex interactions of S. aureus with the host immune system to moderate invasiveness and favour chronic infections. It is the first example of a conserved small RNA in S. aureus functioning as a virulence suppressor of acute infections. Because S. aureus is essentially a human commensal, we propose that RsaA has been positively selected through evolution to support commensalism and saprophytic interactions with the host.

  12. Matrix-assisted laser desorption ionization-time of flight Mass spectrometry can detect Staphylococcus aureus clonal complex 398.

    Science.gov (United States)

    Sauget, Marlène; van der Mee-Marquet, Nathalie; Bertrand, Xavier; Hocquet, Didier

    2016-08-01

    Within the last decade methicillin-resistant Staphylococcus aureus belonging to CC398 has become a worldwide threat associated with livestock. More recently, methicillin-susceptible S. aureus (MSSA) belonging to CC398 have been increasingly reported as a cause of invasive infections in patients without livestock contact. It appears therefore necessary to implement a convenient tool for the surveillance this emerging pathogen. We evaluated the MALDI-TOF MS as a tool for rapid detection of S. aureus CC398. We used 626 S. aureus isolates characterized by a CC398-specific PCR, to constitute independent training (300 isolates including 60 isolates CC398) and validation sets (326 isolates including 82 isolates CC398). Fifteen peak biomarkers of CC398 were identified from the mass spectra of the training set. Ninety four % (307 of 326) of strains of the validation set were well assigned with an overall sensitivity of 93% and a specificity of 95%. Six CC398 and 13 non-CC398 isolates were misclassified. With MALDI-TOF MS, clinical laboratories could rapidly detect S. aureus CC398 associated with a higher mortality in hospitalized patients. PMID:27192668

  13. Impact of the High-Affinity Proline Permease Gene (putP) on the Virulence of Staphylococcus aureus in Experimental Endocarditis

    OpenAIRE

    Bayer, Arnold S.; Coulter, Silvija N.; Stover, C. Kendall; Schwan, William R.

    1999-01-01

    Staphylococcus aureus causes a wide variety of invasive human infections. However, delineation of the genes which are essential for the in vivo survival of this pathogen has not been accomplished to date. Using signature tag mutagenesis techniques and large mutant pool screens, previous investigators identified several major gene classes as candidate essential gene loci for in vivo survival; these include genes for amino acid transporters, oligopeptide transporters, and lantibiotic synthesis ...

  14. Staphylococcus aureus Aggregation and Coagulation Mechanisms, and Their Function in Host-Pathogen Interactions.

    Science.gov (United States)

    Crosby, H A; Kwiecinski, J; Horswill, A R

    2016-01-01

    The human commensal bacterium Staphylococcus aureus can cause a wide range of infections ranging from skin and soft tissue infections to invasive diseases like septicemia, endocarditis, and pneumonia. Muticellular organization almost certainly contributes to S. aureus pathogenesis mechanisms. While there has been considerable focus on biofilm formation and its role in colonizing prosthetic joints and indwelling devices, less attention has been paid to nonsurface-attached group behavior like aggregation and clumping. S. aureus is unique in its ability to coagulate blood, and it also produces multiple fibrinogen-binding proteins that facilitate clumping. Formation of clumps, which are large, tightly packed groups of cells held together by fibrin(ogen), has been demonstrated to be important for S. aureus virulence and immune evasion. Clumps of cells are able to avoid detection by the host's immune system due to a fibrin(ogen) coat that acts as a shield, and the size of the clumps facilitates evasion of phagocytosis. In addition, clumping could be an important early step in establishing infections that involve tight clusters of cells embedded in host matrix proteins, such as soft tissue abscesses and endocarditis. In this review, we discuss clumping mechanisms and regulation, as well as what is known about how clumping contributes to immune evasion. PMID:27565579

  15. Fusarium solani causing quasi-invasive infection of the foot in an immunocompetent middle-aged man from South India

    Directory of Open Access Journals (Sweden)

    Mohan H Kudur

    2013-01-01

    Full Text Available Fusarium solani is commonly found in soil, and it is associated with infections in immunocompromised individuals. Fusaroium solani causing infection in immunocompetent adult male is rare and usually overlooked. We report a case of mycetoma caused by Fusariom solani in an immunocompetent adult male from South India.

  16. High-level aminoglycoside resistance in Enterococcus faecalis and Enterococcus faecium causing invasive infection: Twelve-year surveillance in the Minami Ibaraki Area.

    Science.gov (United States)

    Osuka, Hanako; Nakajima, Jun; Oishi, Tsuyoshi; Funayama, Yasunori; Ebihara, Tsugio; Ishikawa, Hiroichi; Saito, Kazuto; Koganemaru, Hiroshi; Hitomi, Shigemi

    2016-01-01

    We examined prevalence of high-level aminoglycoside resistance (HLAR) in Enterococcus faecalis and Enterococcus faecium causing invasive infection in the Minami Ibaraki Area. Ten strains of both species each, recovered from the blood or the cerebrospinal fluid between 2003 and 2014, were randomly selected every year. High-level resistance to gentamicin (HLR-GM) and streptomycin (HLR-SM) was detected in 34% (41 of 120 strains) and 18% (21) of E. faecalis and 9% (11) and 39% (48) of E. faecium, respectively. In comparisons of the proportions among three four-year periods, HLR-SM among E. faecium was significantly lower in the 2011-2014 period. All strains with HLR-GM were positive for the aac(6')-Ie-aph(2″)-Ia gene. The ant(6')-Ia gene was detected in all with HLR-SM except for one E. faecalis strain. The present study showed that prevalence of HLR-GM among E. faecalis and E. faecium causing invasive infection in this area was nearly equivalent to that described in previous studies in Japan and that proportions of strains with HLAR did not vary during the study period except for that of HLR-SM among E. faecium.

  17. Alternatives to vancomycin for the treatment of methicillin-resistant Staphylococcus aureus infections.

    Science.gov (United States)

    Micek, Scott T

    2007-09-15

    Vancomycin remains the reference standard for the treatment of systemic infection caused by methicillin-resistant Staphylococcus aureus (MRSA). However, as a result of limited tissue distribution, as well as the emergence of isolates with reduced susceptibility and in vitro resistance to vancomycin, the need for alternative therapies that target MRSA has become apparent. New treatment options for invasive MRSA infections include linezolid, daptomycin, tigecycline, and quinupristin/dalfopristin. Additionally, a number of new anti-MRSA compounds are in development, including novel glycopeptides (dalbavancin, telavancin, and oritavancin), ceftobiprole, and iclaprim. The present article will review clinical issues surrounding the newly marketed and investigational agents with activity against MRSA. PMID:17712745

  18. The health and economic burden of bloodstream infections caused by antimicrobial-susceptible and non-susceptible Enterobacteriaceae and Staphylococcus aureus in European hospitals, 2010 and 2011: a multicentre retrospective cohort study.

    Science.gov (United States)

    Stewardson, Andrew J; Allignol, Arthur; Beyersmann, Jan; Graves, Nicholas; Schumacher, Martin; Meyer, Rodolphe; Tacconelli, Evelina; De Angelis, Giulia; Farina, Claudio; Pezzoli, Fabio; Bertrand, Xavier; Gbaguidi-Haore, Houssein; Edgeworth, Jonathan; Tosas, Olga; Martinez, Jose A; Ayala-Blanco, M Pilar; Pan, Angelo; Zoncada, Alessia; Marwick, Charis A; Nathwani, Dilip; Seifert, Harald; Hos, Nina; Hagel, Stefan; Pletz, Mathias; Harbarth, Stephan

    2016-08-18

    We performed a multicentre retrospective cohort study including 606,649 acute inpatient episodes at 10 European hospitals in 2010 and 2011 to estimate the impact of antimicrobial resistance on hospital mortality, excess length of stay (LOS) and cost. Bloodstream infections (BSI) caused by third-generation cephalosporin-resistant Enterobacteriaceae (3GCRE), meticillin-susceptible (MSSA) and -resistant Staphylococcus aureus (MRSA) increased the daily risk of hospital death (adjusted hazard ratio (HR) = 1.80; 95% confidence interval (CI): 1.34-2.42, HR = 1.81; 95% CI: 1.49-2.20 and HR = 2.42; 95% CI: 1.66-3.51, respectively) and prolonged LOS (9.3 days; 95% CI: 9.2-9.4, 11.5 days; 95% CI: 11.5-11.6 and 13.3 days; 95% CI: 13.2-13.4, respectively). BSI with third-generation cephalosporin-susceptible Enterobacteriaceae (3GCSE) significantly increased LOS (5.9 days; 95% CI: 5.8-5.9) but not hazard of death (1.16; 95% CI: 0.98-1.36). 3GCRE significantly increased the hazard of death (1.63; 95% CI: 1.13-2.35), excess LOS (4.9 days; 95% CI: 1.1-8.7) and cost compared with susceptible strains, whereas meticillin resistance did not. The annual cost of 3GCRE BSI was higher than of MRSA BSI. While BSI with S. aureus had greater impact on mortality, excess LOS and cost than Enterobacteriaceae per infection, the impact of antimicrobial resistance was greater for Enterobacteriaceae. PMID:27562950

  19. Emergence of Panton-Valentine leucocidin-positive ST8-methicillin-resistant Staphylococcus aureus (USA300 clone) in Korea causing healthcare-associated and hospital-acquired bacteraemia.

    Science.gov (United States)

    Jung, J; Song, E H; Park, S Y; Lee, S-R; Park, S-J; Sung, H; Kim, M-N; Kim, S-H; Lee, S-O; Choi, S-H; Woo, J H; Kim, Y S; Chong, Y P

    2016-08-01

    Panton-Valentine leucocidin (PVL)-positive sequence type (ST)8-MRSA-SCCmec IVa (USA300) is the epidemic strain of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) in North America. USA300 is extremely rare in South Korea, and PVL-negative ST72 SCCmec type IVc is the predominant CA-MRSA clone. In a multicentre, prospective cohort study of S. aureus bacteraemia, we identified PVL-positive ST8-MRSA isolates by performing multilocus sequence typing and PCR for PVL. We analyzed the clinical characteristics of patients with PVL-positive ST8-MRSA bacteraemia, and performed SCCmec, spa, and agr typing, PCR for arginine catabolic mobile element (ACME), virulence gene profiling, and pulsed-field gel electrophoresis (PFGE). Among a total of 818 MRSA isolates, we identified ten isolates of PVL-positive ST8-MRSA (USA300) (3 from Hospital D, 4 from Hospital G, and 3 from Hospital A), all of which involved exclusively healthcare-associated (5 isolates) and hospital-acquired bacteraemia (5 isolates). This strain accounted for 8~10 % of the hospital-acquired MRSA bacteraemia in Hospitals D and G. Bacteraemia of unknown origin was the most common type of infection followed by pneumonia. All the isolates were SCCmec type IVa, spa type t008, and agr group I. Eight of the isolates harboured ACME. In a PFGE analysis, four isolates were identical to the USA300 control strain, five differed by a single band, and the remaining one differed by two bands. All the isolates were pulsed-field type USA300. This is the first report of healthcare-associated and hospital-acquired bacteraemia caused by USA300 in South Korea. USA300 seems to be an emerging hospital clone in this country. PMID:27209287

  20. The health and economic burden of bloodstream infections caused by antimicrobial-susceptible and non-susceptible Enterobacteriaceae and Staphylococcus aureus in European hospitals, 2010 and 2011: a multicentre retrospective cohort study

    Science.gov (United States)

    Stewardson, Andrew J; Allignol, Arthur; Beyersmann, Jan; Graves, Nicholas; Schumacher, Martin; Meyer, Rodolphe; Tacconelli, Evelina; De Angelis, Giulia; Farina, Claudio; Pezzoli, Fabio; Bertrand, Xavier; Gbaguidi-Haore, Houssein; Edgeworth, Jonathan; Tosas, Olga; Martinez, Jose A; Ayala-Blanco, M Pilar; Pan, Angelo; Zoncada, Alessia; Marwick, Charis A; Nathwani, Dilip; Seifert, Harald; Hos, Nina; Hagel, Stefan; Pletz, Mathias; Harbarth, Stephan

    2016-01-01

    We performed a multicentre retrospective cohort study including 606,649 acute inpatient episodes at 10 European hospitals in 2010 and 2011 to estimate the impact of antimicrobial resistance on hospital mortality, excess length of stay (LOS) and cost. Bloodstream infections (BSI) caused by third-generation cephalosporin-resistant Enterobacteriaceae (3GCRE), meticillin-susceptible (MSSA) and -resistant Staphylococcus aureus (MRSA) increased the daily risk of hospital death (adjusted hazard ratio (HR) = 1.80; 95% confidence interval (CI): 1.34–2.42, HR = 1.81; 95% CI: 1.49–2.20 and HR = 2.42; 95% CI: 1.66–3.51, respectively) and prolonged LOS (9.3 days; 95% CI: 9.2–9.4, 11.5 days; 95% CI: 11.5–11.6 and 13.3 days; 95% CI: 13.2–13.4, respectively). BSI with third-generation cephalosporin-susceptible Enterobacteriaceae (3GCSE) significantly increased LOS (5.9 days; 95% CI: 5.8–5.9) but not hazard of death (1.16; 95% CI: 0.98–1.36). 3GCRE significantly increased the hazard of death (1.63; 95% CI: 1.13–2.35), excess LOS (4.9 days; 95% CI: 1.1–8.7) and cost compared with susceptible strains, whereas meticillin resistance did not. The annual cost of 3GCRE BSI was higher than of MRSA BSI. While BSI with S. aureus had greater impact on mortality, excess LOS and cost than Enterobacteriaceae per infection, the impact of antimicrobial resistance was greater for Enterobacteriaceae. PMID:27562950

  1. Concentrations of tilmicosin in mammary gland secretions of dairy cows following subcutaneous administration of one or two doses of an experimental preparation of tilmicosin and its efficacy against intramammary infections caused by Staphylococcus aureus.

    Science.gov (United States)

    Mendoza, Jesus; Martínez-Cortés, Ismael; López-Ordaz, Reyes; Gutiérrez, Lilia; Sumano, Hector

    2016-09-01

    OBJECTIVE To determine the concentration of tilmicosin in mammary gland secretions of dairy cows following administration of an experimental preparation once or twice during the dry period (45-day period immediately prior to calving during which cows are not milked) and to evaluate its efficacy for the treatment of cows with intramammary infections (IMIs) caused by Staphylococcus aureus at dry off (cessation of milking; first day of dry period), compared with that of an intramammary infusion of ceftiofur. ANIMALS 172 cows. PROCEDURES Milk samples were collected for microbiological culture 5 days before dry off and at calving and 15 and 30 days after calving. Cows with Staphylococcus IMIs were randomly assigned to receive an experimental preparation of tilmicosin (20 mg/kg, SC) once at dry off (n = 58) or at dry off and again 20 days later (56) or receive a long-acting intramammary preparation of ceftiofur (500 mg/mammary gland; 56) at dry off. Mammary gland secretions were collected from 5 cows in the tilmicosin-treated groups every 5 days after dry off until calving for determination of tilmicosin concentration. RESULTS Mean maximum concentration of tilmicosin in mammary gland secretions ranged from 14.4 to 20.9 μg/mL after the first dose and was 17.1 μg/mL after the second dose. The bacteriologic cure rate was 100% for all 3 treatments. Tilmicosin was detectable for 0 and 18 days after calving in the milk of cows treated with 1 and 2 doses of tilmicosin, respectively. CONCLUSIONS AND CLINICAL RELEVANCE Administration of an experimental preparation of tilmicosin (20 mg/kg, SC) once to dairy cows at dry off might be useful for the treatment of S aureus IMIs. PMID:27580103

  2. The prevalence of methicillin-resistant Staph. aureus strains producing enterotoxin A and B

    Directory of Open Access Journals (Sweden)

    Safiyeh Abbasi

    2016-02-01

    Full Text Available Background: Staphylococcus aureus is a gram positive coccus which is able to cause different kinds of infection in certain condition. The function of this bacteria is to provide the conditions for the invasion of it to the host with the secretion of different sorts of toxins such as Staphylococcus aureus enterotoxin, including important virulence factors that super antigens are all factors digestive inconvenience. Staphylococcus aureus enterotoxin-secreting toxins such conditions provides invasion of host genes. There are different types of SE, but type A enterotoxin (SEA and type B enterotoxin (SEB are the most important types. Therefore, in this study, the prevalence of Staphylococcus aureus toxin-producing enterotoxin genes (SEB, SEA in clinical strains isolated from patients in teaching hospitals of Shahrekord city, Iran, were studied. Methods: This cross-sectional and descriptive study, which was conducted from May 2014 to December 2014. A hundred and ten isolates of Staphylococcus aureus from patients collected over a period of 8 months and were first identified using standard biochemical methods and laboratory. Using standard methods and laboratory tests were identified and compared with the antibiotic oxacillin minimum inhibitory concentration were determined by broth micro dilution, and then they were assessed by polymerase chain reaction (PCR technique. Results: The results indicated that, 110 samples of dairy products infected by Staphylococcus aureus were detected. Two cases (1.8% of these infected samples were carrying both enterotoxin A and enterotoxin B genes. The frequencies of enterotoxin A genes were twenty-six cases (23/6% and The frequencies of enterotoxin B genes were two cases (1/8%, respectively. Conclusion: The detection of enterotoxin A and enterotoxin B genes, shows the most important role they have in bringing about superinfection. The detection of enterotoxin A and B genes, shows the most important role they have in

  3. Prevalence and resistance of commensal Staphylococcus aureus, including meticillin-resistant S aureus, in nine European countries: a cross-sectional study.

    NARCIS (Netherlands)

    Heijer, C.D.J. den; Bijnen, E.M.E. van; Paget, W.J.; Pringle, M.; Goossen, H.; Bruggeman, C.A.; Schellevis, F.G.; Stobberingh, E.E.

    2013-01-01

    Background: Information about the prevalence of Staphylococcus aureus resistance to antimicrobial drugs has mainly been obtained from invasive strains, although the commensal microbiota is thought to be an important reservoir of resistance. We aimed to compare the prevalence of nasal S aureus carria

  4. Prevalence and resistance of commensal Staphylococcus aureus, including meticillin-resistant S aureus, in nine European countries: a cross-sectional study

    NARCIS (Netherlands)

    Heijer, C.D. den; Bijnen, E.M. van; Paget, W.J.; Pringle, M.; Goossens, H.; Bruggeman, C.A.; Schellevis, F.G.; Stobberingh, E.E.

    2013-01-01

    BACKGROUND: Information about the prevalence of Staphylococcus aureus resistance to antimicrobial drugs has mainly been obtained from invasive strains, although the commensal microbiota is thought to be an important reservoir of resistance. We aimed to compare the prevalence of nasal S aureus carria

  5. ICU耐甲氧西林金黄色葡萄球菌感染暴发原因分析及对策%Causes for methicillin-resistant Staphylococcus aureus infection in ICU and its countermeasures

    Institute of Scientific and Technical Information of China (English)

    车红英; 庞晓军; 王小平

    2012-01-01

    目的 分析ICU耐甲氧西林金黄色葡萄球菌(MRSA)感染暴发的原因,探讨预防控制的有效措施.方法 对ICU 2011年1月29日-2月10 日相继发生的4例MRSA肺部感染患者开展流行病学调查,并采取干顶措施控制感染流行.结果 入住ICU<14 d相继有4例患者发生MRSA肺部感染,痰标本中分离到相同药敏谱的MRSA,是一起医院感染暴发;ICU环境取样检测,采集标本116份,其中阳性标本26份,阳性率22.4%;医务人员手、写字台、床间隔离布帘、床栏、床垫等标本分离到相同约敏谱MRSA;采取干预措施,将MRSA感染患者集中隔离,加强工作人员手卫生及医疗环境的清洁、消毒,有效地控制了感染流行.结论 在节假日期间 ICU管理存在疏漏,医疗环境污染严重及医护人员手卫生依从性较差,是造成感染暴发的主要原因.%OBJECTIVE To analyze the causes for outbreak of methicillin-resistant Staphylococcus aureus infection in ICU, and discuss the effective measures for prevention an control. METHODS Totally 4 cases of pulmonary infections caused by methicillin-resistant Staphylococcus aureus from Jan 29 to Feb 10 2011 were developed for epidemiological study, and intervention countermeasures were taken for the control of the prevalence of infection. RESULTS Totally 4 cases with less than 14 days were occurred with methicillin-resistant S. aureus pulmonary infections,MRSA isolated from the sputum samples had the same susceptibility spectrum, and it was an outbreak of nosocomial infection; 116 samples were collected from the environment in ICU, among which 26 were positive samples with the positive rate of 22. 4 % ; the susceptibility spectrum of MRSA isolated from the hands of medical personnel,the desk,isolation bed curtains, bed rails and mattress was same; to take the intervention measures, separate the patients with MRSA infections, and strengthen hand hygiene compliance,cleaning and disinfection of medical

  6. 表皮葡萄球菌与金黄色葡萄球菌感染分布及耐药性分析%Distribution and drug resistance of Staphylococcus epidermidis and St ap hy lococcus aureus causing infections

    Institute of Scientific and Technical Information of China (English)

    谢朝云; 熊芸; 孙静; 杨忠玲

    2015-01-01

    目的:研究临床感染表皮葡萄球菌与金黄色葡萄球菌的药敏差异,为临床合理选用抗菌药物提供科学依据。方法对医院2010年6月-2013年12月临床标本中分离出的表皮葡萄球菌与金黄色葡萄球菌,按照《全国临床检验操作规程》进行病原菌鉴定,药敏试验采用 K‐B纸片法,应用SPSS19.0软件对数据进行统计分析。结果临床共分离表皮葡萄球菌183株占51.12%,金黄色葡萄球菌175株占48.88%,表皮葡萄球菌与金黄色葡萄球菌对常用抗菌药物耐药率均较高,对万古霉素、呋喃妥因、替考拉宁、利奈唑胺、米诺环素耐药率均较低<10.00%,表皮葡萄球菌与金黄色葡萄球菌对苯唑西林、阿莫西林/克拉维酸、克林霉素、红霉素、阿奇霉素、庆大霉素耐药率分别为68.85%与45.71%、20.77%与12%、49.18%与26.86%、73.22%与46.86%、68.85%与48.57%、50.27%与29.14%,差异有统计学意义( P<0.05)。结论表皮葡萄球菌耐药率高于金黄色葡萄球菌应引起重视,合理选用抗菌药物,减少耐药菌株产生。%OBJECTIVE To observe the difference in the drug susceptibility between the Staphylococcus epidermi‐dis and Staphylococcus aureus causing clinical infections so as to provide scientific basis for reasonable clinical use of antibiotics .METHODS From Jun 2010 to Dec 2013 ,the S .epidermidis and S .aureus strains were isolated from the clinical specimens ,then the microbial identification was carried out according to National Clinical Laboratory Operation Procedures ,the drug susceptibility testing was conducted by using K‐B method ,and the statistical anal‐ysis was performed with the use of SPSS19 .0 software .RESULTS A total of 183 strains of S .epidermidis were i‐solated from the clinical specimens ,accounting for 51 .12% ,and 175 strains of S .aureus were isolated ,accounting for 48

  7. Neighborhood socioeconomic deprivation, tumor subtypes, and causes of death after non-metastatic invasive breast cancer diagnosis: a multilevel competing-risk analysis.

    Science.gov (United States)

    Lian, Min; Pérez, Maria; Liu, Ying; Schootman, Mario; Frisse, Ann; Foldes, Ellen; Jeffe, Donna B

    2014-10-01

    The purpose of this study is to examine the associations of neighborhood socioeconomic deprivation and triple-negative breast cancer (TNBC) subtype with causes of death [breast cancer (BC)-specific and non-BC-specific] among non-metastatic invasive BC patients. We identified 3,312 patients younger than 75 years (mean age 53.5 years; 621 [18.8 %] TNBC) with first primary BC treated at an academic medical center from 1999 to 2010. We constructed a census-tract-level socioeconomic deprivation index using the 2000 U.S. Census data and performed a multilevel competing-risk analysis to estimate the hazard ratios (HR) and 95 % confidence intervals (CI) of BC-specific and non-BC-specific mortality associated with neighborhood socioeconomic deprivation and TNBC subtype. The adjusted models controlled for patient sociodemographics, health behaviors, tumor characteristics, comorbidity, and cancer treatment. With a median 62-month follow-up, 349 (10.5 %) patients died; 233 died from BC. In the multivariate models, neighborhood socioeconomic deprivation was independently associated with non-BC-specific mortality (the most- vs. the least-deprived quartile: HR = 2.98, 95 % CI = 1.33-6.66); in contrast, its association with BC-specific mortality was explained by the aforementioned patient-level covariates, particularly sociodemographic factors (HR = 1.15, 95 % CI = 0.71-1.87). TNBC subtype was independently associated with non-BC-specific mortality (HR = 2.15; 95 % CI = 1.20-3.84), while the association between TNBC and BC-specific mortality approached significance (HR = 1.42; 95 % CI = 0.99-2.03, P = 0.057). Non-metastatic invasive BC patients who lived in more socioeconomically deprived neighborhoods were more likely to die as a result of causes other than BC compared with those living in the least socioeconomically deprived neighborhoods. TNBC was associated with non-BC-specific mortality but not BC-specific mortality.

  8. Surgimiento y diseminación de Staphylococcus aureus meticilinorresistente Staphylococcus aureus methicillin-resistant: emergence and dissemination

    Directory of Open Access Journals (Sweden)

    Maria Elena Velázquez-Meza

    2005-10-01

    Full Text Available Las infecciones nosocomiales ocasionadas por cepas de Staphylococcus aureus meticilinorresistentes (SAMR son un problema de salud importante en todo el mundo. Este microorganismo produce una gran variedad de infecciones incluyendo osteomielitis, endocarditis invasora, artritis séptica y septicemia. La multirresistencia es un factor que influye en la persistencia de los SAMR dentro del ámbito hospitalario. La introducción de técnicas de tipificación molecular dentro de las investigaciones epidemiológicas ha provisto nuevas herramientas para conocer el origen y las vías de diseminación de este microorganismo. Una de las conclusiones importantes que han surgido de este tipo de estudios es que un número pequeño de clonas son las responsables de las infecciones estafilocócicas en todo el mundo.Nosocomial infections due to methicillin-resistant Staphylococcus aureus (MRSA is an important health problem worldwide. This microorganism causes a variety of clinical infections, including osteomyelitis, invasive endocarditis, septic arthritis and septicemia. Antimicrobial resistance is a factor that influences the persistence of MRSA in the hospital environment. The introduction of molecular typing techniques in epidemiological investigations has provided new tools for identifying the microorganism's origin and routes of dissemination. One of the most important conclusions that have resulted from these types of studies is that a small number of clones are responsible for most of the staphylococcal infections throughout the world.

  9. Risk factors for Staphylococcus aureus nasal colonization in Danish middle-aged and elderly twins

    DEFF Research Database (Denmark)

    Andersen, P S; Larsen, Lisbeth Aagaard; Fowler, V G;

    2013-01-01

    Staphylococcus aureus is a human commensal bacterium found in the nasal cavity and other body sites. Identifying risk factors for S. aureus nasal carriage is of interest, as nasal carriage is a risk factor for subsequent invasive infection. We recently investigated the influence of host genetics ......, male gender, psoriasis, and atopic diseases. Also, present living on a farm is clearly associated with S. aureus colonization, while smoking had a borderline statistically significant protective effect....

  10. Staphylococcus aureus recruits Cdc42GAP through recycling endosomes and the exocyst to invade human endothelial cells.

    Science.gov (United States)

    Rauch, Liane; Hennings, Kirsten; Trasak, Claudia; Röder, Anja; Schröder, Barbara; Koch-Nolte, Friedrich; Rivera-Molina, Felix; Toomre, Derek; Aepfelbacher, Martin

    2016-08-01

    Activation and invasion of the vascular endothelium by Staphylococcus aureus is a major cause of sepsis and endocarditis. For endothelial cell invasion, S. aureus triggers actin polymerization through Cdc42, N-WASp (also known as WASL) and the Arp2/3 complex to assemble a phagocytic cup-like structure. Here, we show that after stimulating actin polymerization staphylococci recruit Cdc42GAP (also known as ARHGAP1) which deactivates Cdc42 and terminates actin polymerization in the phagocytic cups. Cdc42GAP is delivered to the invading bacteria on recycling endocytic vesicles in concert with the exocyst complex. When Cdc42GAP recruitment by staphylococci was prevented by blocking recycling endocytic vesicles or the exocyst complex, or when Cdc42 was constitutively activated, phagocytic cup closure was impaired and endothelial cell invasion was inhibited. Thus, to complete invasion of the endothelium, staphylococci reorient recycling endocytic vesicles to recruit Cdc42GAP, which terminates Cdc42-induced actin polymerization in phagocytic cups. Analogous mechanisms might govern other Cdc42-dependent cell functions.

  11. Three cases of severely disseminated Staphylococcus aureus infection in patients treated with tocilizumab

    DEFF Research Database (Denmark)

    Nguyen, Mai; Pødenphant, Jan; Ravn, Pernille

    2013-01-01

    -intensive diagnostic work-up and early treatment should be performed. Systematic postmarketing studies are needed to clarify if there is a true increased risk of disseminated S aureus infections. We suggest caution when prescribing tocilizumab to patients with prosthetic joints and/or prior invasive S aureus...

  12. Pneumonia and new methicillin-resistant Staphylococcus aureus clone.

    NARCIS (Netherlands)

    Garnier, Fabien; Tristan, Anne; François, Bruno; Etienne, Jerome; Delage-Corre, Manuella; Martin, Christian; Liassine, Nadia; Wannet, Wim; Denis, François; Ploy, Marie-Cécile

    2006-01-01

    Necrotizing pneumonia caused by Staphylococcus aureus strains carrying the Panton-Valentin leukocidin gene is a newly described disease entity. We report a new fatal case of necrotizing pneumonia. An S. aureus strain with an agr1 allele and of a new sequence type 377 was recovered, representing a ne

  13. Bap, a biofilm matrix protein of Staphylococcus aureus prevents cellular internalization through binding to GP96 host receptor.

    Science.gov (United States)

    Valle, Jaione; Latasa, Cristina; Gil, Carmen; Toledo-Arana, Alejandro; Solano, Cristina; Penadés, José R; Lasa, Iñigo

    2012-01-01

    The biofilm matrix, composed of exopolysaccharides, proteins, nucleic acids and lipids, plays a well-known role as a defence structure, protecting bacteria from the host immune system and antimicrobial therapy. However, little is known about its responsibility in the interaction of biofilm cells with host tissues. Staphylococcus aureus, a leading cause of biofilm-associated chronic infections, is able to develop a biofilm built on a proteinaceous Bap-mediated matrix. Here, we used the Bap protein as a model to investigate the role that components of the biofilm matrix play in the interaction of S. aureus with host cells. The results show that Bap promotes the adhesion but prevents the entry of S. aureus into epithelial cells. A broad analysis of potential interaction partners for Bap using ligand overlayer immunoblotting, immunoprecipitation with purified Bap and pull down with intact bacteria, identified a direct binding between Bap and Gp96/GRP94/Hsp90 protein. The interaction of Bap with Gp96 provokes a significant reduction in the capacity of S. aureus to invade epithelial cells by interfering with the fibronectin binding protein invasion pathway. Consistent with these results, Bap deficient bacteria displayed an enhanced capacity to invade mammary gland epithelial cells in a lactating mice mastitis model. Our observations begin to elucidate the mechanisms by which components of the biofilm matrix can facilitate the colonization of host tissues and the establishment of persistent infections.

  14. Bap, a biofilm matrix protein of Staphylococcus aureus prevents cellular internalization through binding to GP96 host receptor.

    Directory of Open Access Journals (Sweden)

    Jaione Valle

    Full Text Available The biofilm matrix, composed of exopolysaccharides, proteins, nucleic acids and lipids, plays a well-known role as a defence structure, protecting bacteria from the host immune system and antimicrobial therapy. However, little is known about its responsibility in the interaction of biofilm cells with host tissues. Staphylococcus aureus, a leading cause of biofilm-associated chronic infections, is able to develop a biofilm built on a proteinaceous Bap-mediated matrix. Here, we used the Bap protein as a model to investigate the role that components of the biofilm matrix play in the interaction of S. aureus with host cells. The results show that Bap promotes the adhesion but prevents the entry of S. aureus into epithelial cells. A broad analysis of potential interaction partners for Bap using ligand overlayer immunoblotting, immunoprecipitation with purified Bap and pull down with intact bacteria, identified a direct binding between Bap and Gp96/GRP94/Hsp90 protein. The interaction of Bap with Gp96 provokes a significant reduction in the capacity of S. aureus to invade epithelial cells by interfering with the fibronectin binding protein invasion pathway. Consistent with these results, Bap deficient bacteria displayed an enhanced capacity to invade mammary gland epithelial cells in a lactating mice mastitis model. Our observations begin to elucidate the mechanisms by which components of the biofilm matrix can facilitate the colonization of host tissues and the establishment of persistent infections.

  15. 泌乳期乳腺炎患者金黄色葡萄球菌感染毒素及荚膜抗原基因研究%Investigation of encoding genes of cytotoxins,invasive toxins and capsular antigens in Staphylococcus aureus isolated from lactation mastitis patients

    Institute of Scientific and Technical Information of China (English)

    王振勇; 许小敏; 李刚; 沈国松; 方强; 杨胜; 姚丽惠

    2014-01-01

    目的:研究分析泌乳期乳腺炎患者感染金黄色葡萄球菌中的细胞毒素、侵袭毒素及荚膜抗原基因携带状况,为临床治疗提供参考依据。方法收集2013年1-10月医院乳期乳腺炎患者病灶部体液中分离的金黄色葡萄球菌共20株,用 spa基因PCR检测用作金黄色葡萄球菌的分子鉴定,再采用聚合酶链反应(PCR)的方法分析10种细胞毒素基因、6种侵袭毒素基因及2种荚膜抗原基因。结果20株金黄色葡萄球菌每一株均有细胞毒素基因和侵袭毒素基因检出,共检出5种细胞毒素基因:hla、hlb、hlg‐2、pvl、lukE;3种侵袭毒素基因:splB、lip、nuc;2种荚膜抗原基因:cap5基因阳性8株阳性率为40.0%,cap8基因阳性11株阳性率为55.0%,14号株cap5、cap8基因检测均为阴性。结论金黄色葡萄球菌中毒力因子的较高检出率是导致乳腺炎症的病理基础;对泌乳期乳腺炎金黄色葡萄球菌进行10种细胞毒素基因、6种侵袭毒素基因及2种荚膜抗原基因检测尚为国内首次报道。%OBJECTIVE To investigate the distribution of encoding genes of cytotoxins ,invasive toxins ,and capsu‐lar antigens in Staphylococcus aureus isolated from lactation mastitis patients so as to provide guidance for the clin‐ical treatment .METHODS From Jan 2013 to Oct 2013 ,totally 20 strains of S .aureus isolated from lactation mas‐titis patients were collected ,then ,the spa gene was used for molecular identification of S .aureus .Furthermore , encoding genes of 10 kinds of cytotoxins ,6 kinds of invasive toxins ,and 2 kinds of capsular antigens were ana‐lyzed by polymerase‐chain‐reaction (PCR) .RESULTS The encoding genes of cytotoxins and invasive toxins were tested positive in each of the 20 S .aureus strains .Totally 5 kinds of cytotoxins(hla ,hlb ,hlg‐2 ,pvl ,lukE) and 3 kinds of invasive toxins (splB ,lip ,nuc) were tested positive .As for the 2 capsular

  16. Nosocomial Infections and Drug Susceptibility Patterns in Methicillin Sensitive and Methicillin Resistant Staphylococcus aureus

    OpenAIRE

    Sharma, Nitish Kumar; Garg, Raina; Baliga, Shrikala; Bhat K., Gopalkrishna

    2013-01-01

    Aim: Staphylococcus aureus is one of the leading causes of nosocomial infections and is known for its ability to develop resistance to antibiotics. The drug susceptibility pattern of Methicillin Sensitive S. aureus (MSSA) and Methicillin Resistant S. aureus (MRSA) may vary.

  17. Genome Sequences of Four Staphylococcus aureus Strains Isolated from Bovine Mastitis

    OpenAIRE

    Kant, Ravi; Taponen, Suvi; Koort, Joanna; Paulin, Lars; Åvall-Jääskeläinen, Silja; Palva, Airi

    2015-01-01

    Staphylococcus aureus is a major causative agent of mastitis in dairy cows. The pathogenicity of S. aureus may vary; it is able to cause severe clinical mastitis, but most often it is associated with chronic subclinical mastitis. Here, we present the genome assemblies of four S. aureus strains from bovine mastitis.

  18. Genome Sequences of Four Staphylococcus aureus Strains Isolated from Bovine Mastitis.

    Science.gov (United States)

    Kant, Ravi; Taponen, Suvi; Koort, Joanna; Paulin, Lars; Åvall-Jääskeläinen, Silja; Palva, Airi

    2015-01-01

    Staphylococcus aureus is a major causative agent of mastitis in dairy cows. The pathogenicity of S. aureus may vary; it is able to cause severe clinical mastitis, but most often it is associated with chronic subclinical mastitis. Here, we present the genome assemblies of four S. aureus strains from bovine mastitis. PMID:25908141

  19. Minimum inhibitory concentration of ciprofloxacin in combination with hexahydroquinoline derivatives against Staphylococcus aureus

    OpenAIRE

    F Amin Harati; Amini, M; AR Shahverdi; Pourmand MR; Yousefi, M

    2012-01-01

    Background: Staphylococcus aureus is the most common pathogen responsible for skin and soft tissue infections worldwide. Methicillin-resistant S. aureus is a major cause of both nosocomial and community acquired infections. The emergence of antimicrobial-resistant S. aureus is of global concern. Fluoroquinolone antimicrobials including ciprofloxacin, levofloxacin, and moxifloxacin are used to treat skin and soft tissue infections due to S. aureus. Emergence of ciprofloxacin resistance has inc...

  20. A porcine model of haematogenous brain infectionwith staphylococcus aureus

    DEFF Research Database (Denmark)

    Astrup, Lærke Boye; Agerholm, Jørgen Steen; Nielsen, Ole Lerberg;

    2012-01-01

    A PORCINE MODEL OF HAEMATOGENOUS BRAIN INFECTION WITH STAPHYLOCOCCUS AUREUS Astrup Lærke1, Agerholm Jørgen1, Nielsen Ole1, Jensen Henrik1, Leifsson Páll1, Iburg Tine2. 1: Faculty of Health and Medical Sciences, University of Copenhagen, Denmark boye@life.ku.dk 2: National Veterinary Institute......, Uppsala, Sweden Introduction Staphylococcus aureus (S.aureus) is a common cause of sepsis and brain abscesses in man and a frequent cause of porcine pyaemia. Here we present a porcine model of haematogenous S. aureus-induced brain infection. Materials and Methods Four pigs had two intravenous catheters...... inserted surgically, one in a. carotis communis and one in v. jugularis externa. All pigs received 106 CFU/kg body weight S. aureus through the arterial catheter. Bacteria were either suspended in isotonic saline infused at constant flow for 60 minutes (two pigs) or given as a bolus injection of autologoue...

  1. Staphylococcus aureus and Staphylococcus epidermidis Virulence Strains as Causative Agents of Persistent Infections in Breast Implants.

    Directory of Open Access Journals (Sweden)

    Daniela Chessa

    Full Text Available Staphylococcus epidermidis and Staphylococcus aureus are currently considered two of the most important pathogens in nosocomial infections associated with catheters and other medical implants and are also the main contaminants of medical instruments. However because these species of Staphylococcus are part of the normal bacterial flora of human skin and mucosal surfaces, it is difficult to discern when a microbial isolate is the cause of infection or is detected on samples as a consequence of contamination. Rapid identification of invasive strains of Staphylococcus infections is crucial for correctly diagnosing and treating infections. The aim of the present study was to identify specific genes to distinguish between invasive and contaminating S. epidermidis and S. aureus strains isolated on medical devices; the majority of our samples were collected from breast prostheses. As a first step, we compared the adhesion ability of these samples with their efficacy in forming biofilms; second, we explored whether it is possible to determine if isolated pathogens were more virulent compared with international controls. In addition, this work may provide additional information on these pathogens, which are traditionally considered harmful bacteria in humans, and may increase our knowledge of virulence factors for these types of infections.

  2. Methicillin-resistant Staphylococcus aureus transmission

    DEFF Research Database (Denmark)

    Andersen, Leif Percival; Nielsen, Xiaohui

    2015-01-01

    INTRODUCTION: Even though methicillin-resistant Staphylococcus aureus (MRSA) is a common cause of nosocomial infections, it may often be difficult to evaluate the exact route of transmission. METHODS: In this study, we describe four cases of nosocomial transmission of MRSA in a hospital with a low...

  3. Phenotypes and Virulence among Staphylococcus aureus USA100, USA200, USA300, USA400, and USA600 Clonal Lineages.

    Science.gov (United States)

    King, Jessica M; Kulhankova, Katarina; Stach, Christopher S; Vu, Bao G; Salgado-Pabón, Wilmara

    2016-01-01

    Staphylococcus aureus diseases affect ~500,000 individuals per year in the United States. Worldwide, the USA100, USA200, USA400, and USA600 lineages cause many of the life-threatening S. aureus infections, such as bacteremia, infective endocarditis, pneumonia, toxic shock syndrome, and surgical site infections. However, the virulence mechanisms associated with these clonal lineages, in particular the USA100 and USA600 isolates, have been severely understudied. We investigated the virulence of these strains, in addition to strains in the USA200, USA300, and USA400 types, in well-established in vitro assays and in vivo in the rabbit model of infective endocarditis and sepsis. We show in the infective endocarditis and sepsis model that strains in the USA100 and USA600 lineages cause high lethality and are proficient in causing native valve infective endocarditis. Strains with high cytolytic activity or producing toxic shock syndrome toxin 1 (TSST-1) or staphylococcal enterotoxin C (SEC) caused lethal sepsis, even with low cytolytic activity. Strains in the USA100, USA200, USA400, and USA600 lineages consistently contained genes that encode for the enterotoxin gene cluster proteins, SEC, or TSST-1 and were proficient at causing infective endocarditis, while the USA300 strains lacked these toxins and were deficient in promoting vegetation growth. The USA100, USA200, and USA400 strains in our collection formed strong biofilms in vitro, whereas the USA200 and USA600 strains exhibited increased blood survival. Hence, infective endocarditis and lethal sepsis are multifactorial and not intrinsic to any one individual clonal group, further highlighting the importance of expanding our knowledge of S. aureus pathogenesis to clonal lineages causative of invasive disease. IMPORTANCE S. aureus is the leading cause of infective endocarditis in the developed world, affecting ~40,000 individuals each year in the United States, and the second leading cause of bacteremia (D. R

  4. Potassium Uptake Modulates Staphylococcus aureus Metabolism.

    Science.gov (United States)

    Gries, Casey M; Sadykov, Marat R; Bulock, Logan L; Chaudhari, Sujata S; Thomas, Vinai C; Bose, Jeffrey L; Bayles, Kenneth W

    2016-01-01

    As a leading cause of community-associated and nosocomial infections, Staphylococcus aureus requires sophisticated mechanisms that function to maintain cellular homeostasis in response to its exposure to changing environmental conditions. The adaptation to stress and maintenance of homeostasis depend largely on membrane activity, including supporting electrochemical gradients and synthesis of ATP. This is largely achieved through potassium (K(+)) transport, which plays an essential role in maintaining chemiosmotic homeostasis, affects antimicrobial resistance, and contributes to fitness in vivo. Here, we report that S. aureus Ktr-mediated K(+) uptake is necessary for maintaining cytoplasmic pH and the establishment of a proton motive force. Metabolite analyses revealed that K(+) deficiency affects both metabolic and energy states of S. aureus by impairing oxidative phosphorylation and directing carbon flux toward substrate-level phosphorylation. Taken together, these results underline the importance of K(+) uptake in maintaining essential components of S. aureus metabolism. IMPORTANCE Previous studies describing mechanisms for K(+) uptake in S. aureus revealed that the Ktr-mediated K(+) transport system was required for normal growth under alkaline conditions but not under neutral or acidic conditions. This work focuses on the effect of K(+) uptake on S. aureus metabolism, including intracellular pH and carbon flux, and is the first to utilize a pH-dependent green fluorescent protein (GFP) to measure S. aureus cytoplasmic pH. These studies highlight the role of K(+) uptake in supporting proton efflux under alkaline conditions and uncover a critical role for K(+) uptake in establishing efficient carbon utilization. PMID:27340697

  5. The use of nasal mupirocin ointment to prevent Staphylococcus aureus bacteraemias in haemodialysis patients: an analysis of cost- effectiveness

    NARCIS (Netherlands)

    J.R. Boelaert; M. A. Geernaert; C.A. Godard (Claudine); H.W. van Landuyt; Y.A. de Baere

    1991-01-01

    textabstractNasal carriage of Staphylococcus aureus is a risk factor for the development of infections caused by S. aureus in haemodialysis patients. This study compared the incidence of bacteraemia caused by S. aureus during 6 months of use of nasal 2% calcium mupirocin ('Nasal Bactroban') 3-times

  6. Genomics of Natural Populations of Staphylococcus aureus.

    Science.gov (United States)

    Fitzgerald, J Ross; Holden, Matthew T G

    2016-09-01

    Staphylococcus aureus is a major human pathogen and an important cause of livestock infections. The first S. aureus genomes to be published, 15 years ago, provided the first view of genome structure and gene content. Since then, thousands of genomes from a wide array of strains from different sources have been sequenced. Comparison of these sequences has resulted in broad insights into population structure, bacterial evolution, clone emergence and expansion, and the molecular basis of niche adaptation. Furthermore, this information is now being applied clinically in outbreak investigations to inform infection control measures and to determine appropriate treatment regimens. In this review, we summarize some of the broad insights into S. aureus biology gained from the analysis of genomes and discuss future directions and opportunities in this dynamic field of research. PMID:27482738

  7. Genomics of Natural Populations of Staphylococcus aureus.

    Science.gov (United States)

    Fitzgerald, J Ross; Holden, Matthew T G

    2016-09-01

    Staphylococcus aureus is a major human pathogen and an important cause of livestock infections. The first S. aureus genomes to be published, 15 years ago, provided the first view of genome structure and gene content. Since then, thousands of genomes from a wide array of strains from different sources have been sequenced. Comparison of these sequences has resulted in broad insights into population structure, bacterial evolution, clone emergence and expansion, and the molecular basis of niche adaptation. Furthermore, this information is now being applied clinically in outbreak investigations to inform infection control measures and to determine appropriate treatment regimens. In this review, we summarize some of the broad insights into S. aureus biology gained from the analysis of genomes and discuss future directions and opportunities in this dynamic field of research.

  8. The Effect of Essential Oils on Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Seda Ozdikmenli

    2014-05-01

    Full Text Available Diseases caused by Staphylococcus aureus are widespread through the world in spite of developing technology. S. aureus is an important pathogen causing food intoxications besides hospital infections by its antibiotic resistant strains. Nowadays, there has been worldwide increasing concern on usage of natural products to control microorganisms. One of these natural products is essential oils. They are produced from plants especially from spices and composed of many components and volatiles. This review summarizes informative literature on essential oils and their mode of antimicrobial action. In addition, current knowledge on in vitro researches on antibacterial activity of essential oils and food applications to control S. aureus has been discussed.

  9. Use of Dithiothreitol to Dislodge Bacteria From the Biofilm on an Aortic Valve in the Operating Theatre: A Case of Infective Endocarditis Caused by Staphylococcus aureus and Proteus mirabilis.

    Science.gov (United States)

    Rimoldi, Sara G; De Vecchi, Elena; Pagani, Cristina; Zambelli, Agostino; Di Gregorio, Annamaria; Bosisio, Enrica; Vanelli, Paolo; Scrofani, Roberto; Gismondo, Maria R; Cagnoni, Giovanni; Antona, Carlo

    2016-10-01

    This is the first reported case of 2 biofilm-producing bacteria, Staphylococcus aureus and Proteus mirabilis, identified from an aortic valve using an innovative device with dithiothreitol solution, able to dislodge bacterial biofilm. The method is usable in the operating theatre and recommended in infective endocarditis nonresponders to empiric therapy. PMID:27645982

  10. Population Structure of Streptococcus pneumoniae Causing Invasive Disease in Adults in Portugal before PCV13 Availability for Adults: 2008-2011

    Science.gov (United States)

    Horácio, Andreia N.; Silva-Costa, Catarina; Diamantino-Miranda, Jorge; Lopes, Joana P.; Ramirez, Mario; Melo-Cristino, José

    2016-01-01

    Among the 1660 isolates recovered from invasive pneumococcal disease (IPD) in adults (> = 18 yrs) in 2008–2011, a random sample of ≥50% of each serotype (n = 871) was chosen for MLST analysis and evaluation for the presence and type of pilus islands (PIs). The genetic diversity was high with 206 different sequence types (STs) detected, but it varied significantly between serotypes. The different STs represented 80 clonal complexes (CCs) according to goeBURST with the six more frequent accounting for more than half (50.6%) of the isolates—CC156 (serotypes 14, 9V and 23F), CC191 (serotype 7F), CC180 (serotype 3), CC306 (serotype 1), CC62 (serotypes 8 and 11A) and CC230 (serotype 19A). Most of the isolates (n = 587, 67.3%) were related to 29 Pneumococcal Molecular Epidemiology Network recognized clones. The overall proportion of isolates positive for any of the PIs was small (31.9%) and declined gradually during the study period (26.6% in 2011), mostly due to the significant decline of serotype 1 which is associated with PI-2. The changes in serotypes that occurred in adult IPD after the introduction of the seven-valent pneumococcal conjugate vaccine (PCV7) for children were mostly due to the expansion of previously circulating clones, while capsular switching was infrequent and not related to vaccine use. The reduction of IPD caused by PCV7 serotypes in the years following PCV7 implementation did not result in a decline of antimicrobial resistance in part due to the selection of resistant genotypes among serotypes 14 and 19A. PMID:27168156

  11. Investigating Invasives

    Science.gov (United States)

    Lightbody, Mary

    2008-01-01

    Invasive species, commonly known as "invasives," are nonnative plants, animals, and microbes that completely take over and change an established ecosystem. The consequences of invasives' spread are significant. In fact, many of the species that appear on the Endangered Species list are threatened by invasives. Therefore, the topic of invasive…

  12. Omics Approaches for the Study of Adaptive Immunity to Staphylococcus aureus and the Selection of Vaccine Candidates

    OpenAIRE

    Silva Holtfreter; Julia Kolata; Sebastian Stentzel; Stephanie Bauerfeind; Frank Schmidt; Nandakumar Sundaramoorthy; Bröker, Barbara M.

    2016-01-01

    Staphylococcus aureus is a dangerous pathogen both in hospitals and in the community. Due to the crisis of antibiotic resistance, there is an urgent need for new strategies to combat S. aureus infections, such as vaccination. Increasing our knowledge about the mechanisms of protection will be key for the successful prevention or treatment of S. aureus invasion. Omics technologies generate a comprehensive picture of the physiological and pathophysiological processes within cells, tissues, orga...

  13. Characterization of methicillin-resistant Staphylococcus aureus Sequence Type 398

    DEFF Research Database (Denmark)

    Christiansen, Mette Theilgaard

    Staphylococcus aureus is an opportunistic pathogen that colonizes the nares and skin surfaces of several animal species, including man. S. aureus can cause a wide variety of infections ranging from superficial soft tissue and skin infections to severe and deadly systemic infections. Traditionally S....... aureus and methicillin-resistant Staphylococcus aureus (MRSA) have been associated with hospitals, but during the past decades MRSA has emerged in the community and now a new branch of MRSA has been found in association with livestock (LA-MRSA). A specific lineage (multilocus sequence type 398 (ST398...... for LA-MRSA ST398 survival on porcine skin and nasal epithelium ex vivo were identified. These genes could represent targets for de-colonization, which could help prevent further spread and adaption of LA-MRSA ST398. Manuscript III describes the construction of the S. aureus VirulenceFinder database...

  14. Intravenous inoculation of a bat-associated rabies virus causes lethal encephalopathy in mice through invasion of the brain via neurosecretory hypothalamic fibers.

    Directory of Open Access Journals (Sweden)

    Mirjam A R Preuss

    2009-06-01

    Full Text Available The majority of rabies virus (RV infections are caused by bites or scratches from rabid carnivores or bats. Usually, RV utilizes the retrograde transport within the neuronal network to spread from the infection site to the central nervous system (CNS where it replicates in neuronal somata and infects other neurons via trans-synaptic spread. We speculate that in addition to the neuronal transport of the virus, hematogenous spread from the site of infection directly to the brain after accidental spill over into the vascular system might represent an alternative way for RV to invade the CNS. So far, it is unknown whether hematogenous spread has any relevance in RV pathogenesis. To determine whether certain RV variants might have the capacity to invade the CNS from the periphery via hematogenous spread, we infected mice either intramuscularly (i.m. or intravenously (i.v. with the dog-associated RV DOG4 or the silver-haired bat-associated RV SB. In addition to monitoring the progression of clinical signs of rabies we used immunohistochemistry and quantitative reverse transcription polymerase chain reaction (qRT-PCR to follow the spread of the virus from the infection site to the brain. In contrast to i.m. infection where both variants caused a lethal encephalopathy, only i.v. infection with SB resulted in the development of a lethal infection. While qRT-PCR did not reveal major differences in virus loads in spinal cord or brain at different times after i.m. or i.v. infection of SB, immunohistochemical analysis showed that only i.v. administered SB directly infected the forebrain. The earliest affected regions were those hypothalamic nuclei, which are connected by neurosecretory fibers to the circumventricular organs neurohypophysis and median eminence. Our data suggest that hematogenous spread of SB can lead to a fatal encephalopathy through direct retrograde invasion of the CNS at the neurovascular interface of the hypothalamus-hypophysis system

  15. Staphylococcus aureus Transcriptome Architecture

    DEFF Research Database (Denmark)

    Mäder, Ulrike; Nicolas, Pierre; Depke, Maren;

    2016-01-01

    Staphylococcus aureus is a major pathogen that colonizes about 20% of the human population. Intriguingly, this Gram-positive bacterium can survive and thrive under a wide range of different conditions, both inside and outside the human body. Here, we investigated the transcriptional adaptation of S....... aureus HG001, a derivative of strain NCTC 8325, across experimental conditions ranging from optimal growth in vitro to intracellular growth in host cells. These data establish an extensive repertoire of transcription units and non-coding RNAs, a classification of 1412 promoters according...... to their dependence on the RNA polymerase sigma factors SigA or SigB, and allow identification of new potential targets for several known transcription factors. In particular, this study revealed a relatively low abundance of antisense RNAs in S. aureus, where they overlap only 6% of the coding genes, and only 19...

  16. Antibiotic-mediated selection of quorum-sensing-negative Staphylococcus aureus

    DEFF Research Database (Denmark)

    Paulander, Wilhelm Erik Axel; Varming, Anders Nissen; Bæk, Kristoffer Torbjørn;

    2012-01-01

    -acquired S. aureus infections and suggest that the adaptability of S. aureus to antibiotics involves the agr locus. IMPORTANCE: Staphylococcus aureus is the most frequently isolated pathogen in intensive care units and a common cause of nosocomial infections, resulting in a high degree of morbidity......Staphylococcus aureus is a human commensal that at times turns into a serious bacterial pathogen causing life-threatening infections. For the delicate control of virulence, S. aureus employs the agr quorum-sensing system that, via the intracellular effector molecule RNAIII, regulates virulence gene...... increases the agr-mediated fitness cost by inducing the expression of RNAIII. Thus, the extensive use of antibiotics in hospitals may explain why agr-negative variants are frequently isolated from hospital-acquired S. aureus infections but rarely found among community-acquired S. aureus strains. Importantly...

  17. EARSS: European Antimicrobial Resistance Surveillance System; data from the Netherlands .Incidence and resistance rates for Streptococcus pneumoniae and Staphylococcus aureus

    NARCIS (Netherlands)

    Goettsch WG; Neeling AJ de; CIE; LIO

    2001-01-01

    In a porspective prevalence and incidence survey in The Netherlands in 1999 antimicrobial susceptibility data on invasive Streptococcus pneumoniae and Staphylococcus aureus infections were collected sithin the framework of European Antomicrobial Resistance Surveillance System (EARSS). The EARSS proj

  18. Fibronectin-binding protein acts as Staphylococcus aureus invasin via fibronectin bridging to integrin alpha5beta1

    NARCIS (Netherlands)

    Sinha, B; François, P P; Nüsse, O; Foti, M; Hartford, O M; Vaudaux, P; Foster, T J; Lew, D P; Herrmann, M; Krause, K H

    1999-01-01

    The ability of Staphylococcus aureus to invade mammalian cells may explain its capacity to colonize mucosa and to persist in tissues after bacteraemia. To date, the underlying molecular mechanisms of cellular invasion by S. aureus are unknown, despite its high prevalence and difficulties in treatmen

  19. Duplex Identification of Staphylococcus aureus by Aptamer and Gold Nanoparticles.

    Science.gov (United States)

    Chang, Tianjun; Wang, Libo; Zhao, Kexu; Ge, Yu; He, Meng; Li, Gang

    2016-06-01

    Staphylococcus aureus is the top common pathogen causing infections and food poisoning. Identification of S. aureus is crucial for the disease diagnosis and regulation of food hygiene. Herein, we report an aptamer-AuNPs based method for duplex identification of S. aureus. Using AuNPs as an indicator, SA23, an aptamer against S. aureus, can well identify its target from Escherichia coli, Listeria monocytogenes and Pseudomonas aeruginosa. Furthermore, we find citrate-coated AuNPs can strongly bind to S. aureus, but not bind to Salmonella enterica and Proteus mirabilis, which leads to different color changes in salt solution. This colorimetric response is capable of distinguishing S. aureus from S. enteritidis and P. mirabilis. Thus, using the aptasensor and AuNPs together, S. aureus can be accurately identified from the common pathogens. This duplex identification system is a promising platform for simple visual identification of S. aureus. Additionally, in the aptasensing process, bacteria are incubated with aptamers and then be removed before the aptamers adding to AuNPs, which may avoid the interactions between bacteria and AuNPs. This strategy can be potentially applied in principle to detect other cells by AuNPs-based aptasensors. PMID:27427591

  20. Duplex Identification of Staphylococcus aureus by Aptamer and Gold Nanoparticles.

    Science.gov (United States)

    Chang, Tianjun; Wang, Libo; Zhao, Kexu; Ge, Yu; He, Meng; Li, Gang

    2016-06-01

    Staphylococcus aureus is the top common pathogen causing infections and food poisoning. Identification of S. aureus is crucial for the disease diagnosis and regulation of food hygiene. Herein, we report an aptamer-AuNPs based method for duplex identification of S. aureus. Using AuNPs as an indicator, SA23, an aptamer against S. aureus, can well identify its target from Escherichia coli, Listeria monocytogenes and Pseudomonas aeruginosa. Furthermore, we find citrate-coated AuNPs can strongly bind to S. aureus, but not bind to Salmonella enterica and Proteus mirabilis, which leads to different color changes in salt solution. This colorimetric response is capable of distinguishing S. aureus from S. enteritidis and P. mirabilis. Thus, using the aptasensor and AuNPs together, S. aureus can be accurately identified from the common pathogens. This duplex identification system is a promising platform for simple visual identification of S. aureus. Additionally, in the aptasensing process, bacteria are incubated with aptamers and then be removed before the aptamers adding to AuNPs, which may avoid the interactions between bacteria and AuNPs. This strategy can be potentially applied in principle to detect other cells by AuNPs-based aptasensors.

  1. [Pathogenesis of invasive fungal infections].

    Science.gov (United States)

    Garcia-Vidal, Carolina; Carratalà, Jordi

    2012-03-01

    Invasive fungal infections remain a life-threatening disease. The development of invasive fungal disease is dependent on multiple factors, such us colonization and efficient host immune response. We aimed to review the pathogenesis of invasive fungal infections, in particular, those caused by Candida and Aspergillus. For this we propose, to describe the fungal characteristics, to detail the host defence mechanisms against fungus and to analyse the host risk factors for invasive fungal infection.

  2. Identification of the ClpX Regulon in Staphylococcus aureus

    DEFF Research Database (Denmark)

    Jelsbak, Lotte; Thomsen, Line Elnif; Ingmer, Hanne;

    Staphyloccous aureus is a major human pathogen capable of causing a wide spectrum of infections ranging from superficial wound infections to life-threatening endocarditis and toxic shock syndrome. Essential for S. aureus virulence is a large number of cell-surface-associated proteins and secreted...... we show here that almost 400 genes (15%) are influenced by the clpX deletion. Furthermore, ClpX not only regulates many virulence factors, but rather serves as a global regulator of central functions for S. aureus lifestyle and pathogenicity....

  3. Erythromycin resistance caused by erm(A) subclass erm(TR) in a Danish invasive pneumococcal isolate: Are erm(A) pneumococcal isolates overlooked?

    DEFF Research Database (Denmark)

    Lambertsen, L.; Ekelund, K.; Hansen, D.S.;

    2008-01-01

    Erm(A) is rarely reported as erythromycin resistance determinant in pneumococci. One invasive erm(A) isolate was initially tested intermediate erythromycin resistant using E-test. However, upon re-testing it was resistant, thus close to the breakpoint value. This may be a reason why erm(A) only...

  4. Expression and inducibility in Staphylococcus aureus of the mecA gene, which encodes a methicillin-resistant S. aureus-specific penicillin-binding protein.

    OpenAIRE

    Ubukata, K; Nonoguchi, R; Matsuhashi, M; Konno, M

    1989-01-01

    A beta-lactam-sensitive strain of Staphylococcus aureus could be converted to methicillin resistance by the introduction of a plasmid carrying the 4.3-kilobase HindIII chromosomal DNA fragment which encoded the mecA gene from a methicillin-resistant S. aureus. Transformant cells produced methicillin-resistant S. aureus-specific penicillin-binding protein constitutively, and additional insertion of an inducible penicillinase plasmid caused production of the pencillin-binding protein to become ...

  5. Les espèces exotiques envahissantes, pour une remise en cause des paradigmes écologiques Invasive species: challenging the ecological paradigms

    Directory of Open Access Journals (Sweden)

    LEVEQUE, Christian, TABACCHI, Eric, MENOZZI, Marie-Jo

    2012-02-01

    Full Text Available Les espèces exotiques font couler beaucoup d'encre et sont souvent présentées de manière négative. On les accuse de devenir envahissantes, d'entrer en concurrence avec les espèces autochtones, d'entraîner un dysfonctionnement des écosystèmes, et d'avoir un coût élevé pour l'économie. Cet article propose de dépasser ces points de vue parfois simplistes et réducteurs, en étudiant l'aspect sémantique et les définitions données à ces espèces, pour ensuite élaborer des pistes de réflexion sur la façon de composer avec elles.As a result of the high human pressure on aquatic and semiaquatic ecosystems, new species introduced from several parts of the World are increasingly observed. Some of these species become invasive and are expected to threaten biodiversity and ecosystem functioning. This paper is an attempt to disentangle scientific facts or theories from conventional wisdom based on subjective perception or cultural pictures. Especially, we point out that in face of a real threat for biodiversity and ecosystem functioning, invasive species may have positive effects or uses. Several issues in invasion management are examined. While characteristics of invasive species cannot easily be predicted, many invasions take place in previously modified ecosystems. Furthermore, invaders eradication is not always the best answer for targeting self-sustainable healthy ecosystems. Since exotic species will irrevocably increase in proportion within our ecological communities in the next future, one may be ready to adapt to this novel biodiversity by accepting or managing the presence of some invaders.

  6. Exfoliative Toxins of Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Michal Bukowski

    2010-05-01

    Full Text Available Staphylococcus aureus is an important pathogen of humans and livestock. It causes a diverse array of diseases, ranging from relatively harmless localized skin infections to life-threatening systemic conditions. Among multiple virulence factors, staphylococci secrete several exotoxins directly associated with particular disease symptoms. These include toxic shock syndrome toxin 1 (TSST-1, enterotoxins, and exfoliative toxins (ETs. The latter are particularly interesting as the sole agents responsible for staphylococcal scalded skin syndrome (SSSS, a disease predominantly affecting infants and characterized by the loss of superficial skin layers, dehydration, and secondary infections. The molecular basis of the clinical symptoms of SSSS is well understood. ETs are serine proteases with high substrate specificity, which selectively recognize and hydrolyze desmosomal proteins in the skin. The fascinating road leading to the discovery of ETs as the agents responsible for SSSS and the characterization of the molecular mechanism of their action, including recent advances in the field, are reviewed in this article.

  7. [Staphylococcus aureus and antibiotic resistance].

    Science.gov (United States)

    Sancak, Banu

    2011-07-01

    After the report of first case of methicillin-resistant Staphylococcus aureus (MRSA) in 1961, MRSA become a major problem worldwide. Over the last decade MRSA strains have emerged as serious pathogens in nosocomial and community settings. Glycopeptides (vancomycin and teicoplanin) are still the current mainstay of therapy for infections caused by MRSA. In the last decade dramatic changes have occurred in the epidemiology of MRSA infections. The isolates with reduced susceptibility and in vitro resistance to vancomycin have emerged. Recently, therapeutic alternatives such as quinupristin/dalfopristin, linezolid, tigecycline and daptomycin have been introduced into clinical practice for treating MRSA infections. Nevertheless, these drugs are only approved for certain indication and resistance has already been reported. In this review, the new information on novel drugs for treating MRSA infections and the resistance mechanisms of these drugs were discussed. PMID:21935792

  8. Methicillin-Resistant Staphylococcus aureus Ocular Infection in Taiwan

    OpenAIRE

    Kang, Yu-Chuan; Hsiao, Ching-Hsi; Yeh, Lung-Kun; Ma, David H. K.; Chen, Phil Y. F.; Lin, Hsin-Chiung; Tan, Hsin-Yuan; Chen, Hung-Chi; Chen, Shin-Yi; Huang, Yhu-Chering

    2015-01-01

    Abstract Methicillin-resistant Staphylococcus aureus (MRSA) infection is an important public health issue. This observational study aimed to characterize clinical features, antibiotic susceptibility, and genotypes of ocular infections caused by MRSA based on the clinical and molecular definitions of community-associated (CA) and healthcare-associated (HA) strains. Fifty-nine patients with culture-proven S aureus ocular infection were enrolled from January 1, 2010 to December 31, 2011 at Chang...

  9. Antimicrobial peptide exposure selects for Staphylococcus aureus resistance to human defence peptides

    DEFF Research Database (Denmark)

    Kubicek-Sutherland, Jessica Z.; Lofton, Hava; Vestergaard, Martin;

    2016-01-01

    Background: The clinical development of antimicrobial peptides (AMPs) is currently under evaluation to combat the rapid increase in MDR bacterial pathogens. However, many AMPs closely resemble components of the human innate immune system and the ramifications of prolonged bacterial exposure to AMPs...... suggest that therapeutic use of AMPs could select for virulent mutants with crossresistance to human innate immunity as well as antibiotic therapy. Thus, therapeutic use of AMPs and the implications of cross-resistance need to be carefully monitored and evaluated....... of sepsis. Results: AMP-resistant Staphylococcus aureus mutants often displayed little to no fitness cost and caused invasive disease in mice. Further, this phenotype coincided with diminished susceptibility to both clinically prescribed antibiotics and human defence peptides. Conclusions: These findings...

  10. mecA 基因与金黄色葡萄球菌感染患者的耐药性研究%Research of mecA gene and drug resistance of Staphy lococcus aureus causing infections

    Institute of Scientific and Technical Information of China (English)

    王欢; 沙栋杰; 邱莲女; 费鲜明; 周永列

    2015-01-01

    目的:检测mecA基因在金黄色葡萄球菌(SAU)中的分布,探讨mecA基因与SAU耐药性的关系。方法用琼脂扩散法检测临床分离的112株SAU对常用抗菌药物的耐药性,采用 PCR方法检测SAU中的 mecA基因,并分析 mecA基因和SAU耐药性的关系。结果耐甲氧西林金黄色葡萄球菌(MRSA)59株占52.68%,甲氧西林敏感金黄色葡萄球菌(MSSA)53株占47.32%;MRSA对青霉素G耐药率为100.00%,对红霉素和四环素耐药率分别为69.49%和47.46%,对万古霉素和替考拉宁敏感;MSSA对青霉素G耐药率最高,为88.68%,其次为红霉素和克林霉素,耐药率分别为60.38%和28.30%,对苯唑西林、利福平、万古霉素和替考拉宁敏感;SAU 耐药株主要从痰液中分离,神经外科分布最多;mecA基因总阳性率为51.79%,其中M RSA 中阳性率为88.14%, MSSA中阳性率为11.32%,mecA 基因阳性的 MSSA 比 mecA 基因阴性有更高的耐药性。结论 MRSA 中mecA基因阳性率极高,在金黄色葡萄球菌的耐药中发挥重要作用。%OBJECTIVE To explore the distribution of mecA gene in Staphylococcus aureus and study the relation‐ship between the mecA gene and the drug resistance of S .aureus .METHODS The drug resistance rates of 112 clini‐cal isolates of S .aureus to commonly used antibiotics were determined by using agar diffusion method ,the mecA gene in the S .aureus strains was detected with the use of PCR ,and the relationship between the mecA gene and the drug resistance of the S .aureus strains was observed .RESULTS The methicillin‐resistant S .aureus (MRSA) accounted for 52 .68% (59 strains) ,and the methicillin‐susceptible S .aureus (MSSA) accounted for 47 .32% (53 strains) .The drug resistance rate of MRSA to penicillin G was 100 .00% ,the drug resistance rates to erythromy‐cin and tetracycline were 69 .49% and 47 .46% ,respectively ,and the MRSA strains

  11. Simulation study of contamination caused by Staphylococcus aureus during yogurt fermentation%酸奶制作中金黄色葡萄球菌污染的模拟实验研究

    Institute of Scientific and Technical Information of China (English)

    曾娟; 赖熙梅; 吴正云

    2011-01-01

    Staphylococcus aureus is a food-borne pathogen which has a high detection rate in dairy products. In this paper, dynamic behavior of lactic acid bacteria and S. Aureus during yogurt fermentation was investigated by means of simulation experiments, and staphylococcal enterotoxtn A (SEA) level in contaminated yoghurt was estimated, as well. Results showed that, growth rate and the maximum amount of S. Aureus increased significantly under the conditions of lower fermentation temperature, higher milk powder addition, or higher contamination level of S. Aureus. Calculated according to literatures, consumption less than 1300ml of this contaminated yogurt had little risk for an adult has weight of 61kg, but the product might be dangerous for an infant This study provided a reference for process control of yogurt fermentation as well as safely consumption of yogurt.%金黄色葡萄球菌是乳制品中检出率较高的食源性致病菌.该论文采用模拟实验的方式,探讨了在金黄色葡萄球菌污染的情况下,酸奶制作过程中乳酸菌和金黄色葡萄球菌消长的动态规律,并初步估计了被污染酸奶中金黄色葡萄球菌耐热肠毒素的危害水平.研究结果显示,当发酵温度偏低、奶粉添加量偏高和金葡菌污染程度较高时,金黄色葡萄球菌生长速率和最大菌数明显提高.参考有关文献进行估算,对于一个体重为61kg的成人来说,如果酸奶食用量少于1300mL,一般不会有酸奶金黄色葡萄球菌耐热肠毒素中毒的危险;但对于儿童来说则有一定风险.本研究对于酸奶制作工艺控制及酸奶的安全消费具有参考意义.

  12. Salinomycin causes migration and invasion of human fibrosarcoma cells by inducing MMP-2 expression via PI3-kinase, ERK-1/2 and p38 kinase pathways.

    Science.gov (United States)

    Yu, Seon-Mi; Kim, Song Ja

    2016-06-01

    Salinomycin (SAL) is a polyether ionophore antibiotic that has recently been shown to regulate a variety of cellular responses in various human cancer cells. However, the effects of SAL on metastatic capacity of HT1080 human fibrosarcoma cells have not been elucidated. We investigated the effect of SAL on migration and invasion, with emphasis on the expression and activation of matrix metalloproteinase (MMP)-2 in HT1080 human fibrosarcoma cells. Treatment of SAL promoted the expression and activation of MMP-2 in a dose- and time-dependent manner, as detected by western blot analysis, gelatin zymography, and real-time polymerase chain reaction. SAL also increased metastatic capacities, as determined by an increase in the migration and invasion of cells using the wound healing assay and the invasion assay, respectively. To confirm the detailed molecular mechanisms of these effects, we measured the activation of phosphoinositide 3 kinase (PI3-kinase) and mitogen-activated protein kinase (MAPK)s (ERK-1/2 and p38 kinase), as detected by the phosphorylated proteins through western blot analysis. SAL treatment increased the phosphorylation of Akt and MAPKs. Inhibition of PI3-kinase, ERK-1/2, and p38 kinase with LY294002, PD98059, and SB203580, respectively, in the presence of SAL suppressed the metastatic capacity by reducing MMP-2 expression, as determined by gelatin zymography. Our results indicate that the PI3-kinase and MAPK signaling pathways are involved in migration and invasion of HT1080 through induction of MMP-2 expression and activation. In conclusion, SAL significantly increases the metastatic capacity of HT1080 cells by inducing MMP-2 expression via PI3-kinase and MAPK pathways. Our results suggest that SAL may be a potential agent for the study of cancer metastatic capacities. PMID:27035160

  13. Community-Based Outbreaks in Vulnerable Populations of Invasive Infections Caused by Streptococcus pneumoniae Serotypes 5 and 8 in Calgary, Canada

    OpenAIRE

    Otto G Vanderkooi; Church, Deirdre L.; MacDonald, Judy; Zucol, Franziska; Kellner, James D

    2011-01-01

    Background Outbreaks of invasive pneumococcal disease (IPD) typically occur within institutions. Beginning in 2005, we detected an increase in serotype (ST) 5 and ST8 IPD cases, predominantly in homeless persons living in an open community. Methodology/Principal Findings CASPER (Calgary Area S. pneumoniae Epidemiology Research) surveillance study of all IPD (sterile site isolates) in our region (pop ∼1,100,000). Interviews and chart reviews of all cases and all isolates phenotypically analyze...

  14. Salinomycin causes migration and invasion of human fibrosarcoma cells by inducing MMP-2 expression via PI3-kinase, ERK-1/2 and p38 kinase pathways.

    Science.gov (United States)

    Yu, Seon-Mi; Kim, Song Ja

    2016-06-01

    Salinomycin (SAL) is a polyether ionophore antibiotic that has recently been shown to regulate a variety of cellular responses in various human cancer cells. However, the effects of SAL on metastatic capacity of HT1080 human fibrosarcoma cells have not been elucidated. We investigated the effect of SAL on migration and invasion, with emphasis on the expression and activation of matrix metalloproteinase (MMP)-2 in HT1080 human fibrosarcoma cells. Treatment of SAL promoted the expression and activation of MMP-2 in a dose- and time-dependent manner, as detected by western blot analysis, gelatin zymography, and real-time polymerase chain reaction. SAL also increased metastatic capacities, as determined by an increase in the migration and invasion of cells using the wound healing assay and the invasion assay, respectively. To confirm the detailed molecular mechanisms of these effects, we measured the activation of phosphoinositide 3 kinase (PI3-kinase) and mitogen-activated protein kinase (MAPK)s (ERK-1/2 and p38 kinase), as detected by the phosphorylated proteins through western blot analysis. SAL treatment increased the phosphorylation of Akt and MAPKs. Inhibition of PI3-kinase, ERK-1/2, and p38 kinase with LY294002, PD98059, and SB203580, respectively, in the presence of SAL suppressed the metastatic capacity by reducing MMP-2 expression, as determined by gelatin zymography. Our results indicate that the PI3-kinase and MAPK signaling pathways are involved in migration and invasion of HT1080 through induction of MMP-2 expression and activation. In conclusion, SAL significantly increases the metastatic capacity of HT1080 cells by inducing MMP-2 expression via PI3-kinase and MAPK pathways. Our results suggest that SAL may be a potential agent for the study of cancer metastatic capacities.

  15. Indole and 7-benzyloxyindole attenuate the virulence of Staphylococcus aureus.

    Science.gov (United States)

    Lee, Jin-Hyung; Cho, Hyun Seob; Kim, Younghoon; Kim, Jung-Ae; Banskota, Suhrid; Cho, Moo Hwan; Lee, Jintae

    2013-05-01

    Human pathogens can readily develop drug resistance due to the long-term use of antibiotics that mostly inhibit bacterial growth. Unlike antibiotics, antivirulence compounds diminish bacterial virulence without affecting cell viability and thus, may not lead to drug resistance. Staphylococcus aureus is a major agent of nosocomial infections and produces diverse virulence factors, such as the yellow carotenoid staphyloxanthin, which promotes resistance to reactive oxygen species (ROS) and the host immune system. To identify novel antivirulence compounds, bacterial signal indole present in animal gut and diverse indole derivatives were investigated with respect to reducing staphyloxanthin production and the hemolytic activity of S. aureus. Treatment with indole or its derivative 7-benzyloxyindole (7BOI) caused S. aureus to become colorless and inhibited its hemolytic ability without affecting bacterial growth. As a result, S. aureus was more easily killed by hydrogen peroxide (H₂O₂) and by human whole blood in the presence of indole or 7BOI. In addition, 7BOI attenuated S. aureus virulence in an in vivo model of nematode Caenorhabditis elegans, which is readily infected and killed by S. aureus. Transcriptional analyses showed that both indole and 7BOI repressed the expressions of several virulence genes such as α-hemolysin gene hla, enterotoxin seb, and the protease genes splA and sspA and modulated the expressions of the important regulatory genes agrA and sarA. These findings show that indole derivatives are potential candidates for use in antivirulence strategies against persistent S. aureus infection. PMID:23318836

  16. Future challenges and treatment of Staphylococcus aureus bacteremia with emphasis on MRSA

    DEFF Research Database (Denmark)

    Rasmussen, Rasmus V; Fowler, Vance G; Skov, Robert;

    2011-01-01

    . Compounding this problem is the growing prevalence of methicillin-resistant S. aureus (MRSA) and the dwindling efficacy of vancomycin, long the treatment of choice for this pathogen. Despite the recent availability of several new antibiotics for S. aureus, new strategies for treatment and prevention......Staphylococcus aureus bacteremia (SAB) is an urgent medical problem due to its growing frequency and its poor associated outcome. As healthcare delivery increasingly involves invasive procedures and implantable devices, the number of patients at risk for SAB and its complications is likely to grow...

  17. Role of GapC in the pathogenesis of Staphylococcus aureus.

    Science.gov (United States)

    Kerro-Dego, Oudessa; Prysliak, Tracy; Perez-Casal, Jose; Potter, Andrew A

    2012-05-01

    Staphylococcus aureus is recognized worldwide as a major pathogen causing clinical or subclinical intramammary infections in lactating cows, sheep and goats. S. aureus produces a wide arsenal of cell surface and extracellular proteins involved in virulence. Among these are two conserved proteins with glyceraldehyde-3-phosphate dehydrogenase (GAPDH) activity named glyceraldehyde-3-phosphate dehydrogenase-B (GapB) and -C (GapC). In this study, we used the S. aureus wild type strain RN6390 and its isogenic gapC mutant H330 in in vitro and in vivo studies and determined that the S. aureus GapC protein plays a role on adherence to and internalization into bovine mammary epithelial (MAC-T) cells. In addition, we found that S. aureus H330 did not caused mastitis after an experimental infection of ovine mammary glands. Together, these results show that GapC is important in the pathogenesis of S. aureus mastitis. PMID:22176759

  18. Mastitis Bovina: Resistencia a antibióticos de cepas de Staphylococcus aureus asiladas de leche (Bovine Mastitis: Antimicrobial resistance of Staphylococcus aureus strains isolated from milk

    Directory of Open Access Journals (Sweden)

    Pellegrino, MS

    2011-07-01

    Full Text Available ResumenLa mastitis bovina es considerada la enfermedad infecciosa del ganado lechero de mayor impacto económico mundial, siendo Staphylococcus aureus el principal agente patógeno en muchos países.SummaryBovine mastitis is a frequent cause of economic loss in worldwide dairy herds, being Staphylococcus aureus the main etiological agent in many countries.

  19. Mastitis Bovina: Resistencia a antibióticos de cepas de Staphylococcus aureus asiladas de leche (Bovine Mastitis: Antimicrobial resistance of Staphylococcus aureus strains isolated from milk)

    OpenAIRE

    Pellegrino, MS; Frola, ID; Odierno, LM; Bogni, CI

    2011-01-01

    ResumenLa mastitis bovina es considerada la enfermedad infecciosa del ganado lechero de mayor impacto económico mundial, siendo Staphylococcus aureus el principal agente patógeno en muchos países.SummaryBovine mastitis is a frequent cause of economic loss in worldwide dairy herds, being Staphylococcus aureus the main etiological agent in many countries.

  20. Evaluation of aptamers labelled with 99mTc for identification of Staphylococcus aureus bacteria

    International Nuclear Information System (INIS)

    Staphylococcus aureus is specie of great medical importance because it is often associated with many infections in humans. This bacterium can cause diseases ranging from simple infections to life-threatening infections such as endocarditis, pneumonia, meningitis, toxic shock syndrome, septicemia, osteomyelitis, among others. S. aureus is the most commonly agent found in infections of the skin and soft tissues, bone infections and bone prostheses. The difficulty in early detection of specific foci caused by bacteria has raised the need to search for new techniques for this purpose. Diagnosis by scintigraphy has advantages over other methods because it is able to identify damage tissues without the need of invasive procedures and is able to perform an early diagnosis even before anatomic changes. Thus, nuclear medicine could contribute to an accurate diagnosis of bacterial infections, since specific radiopharmaceuticals were developed. Aptamers are oligonucleotides that have high affinity and specificity for their molecular targets and are emerging as a new class of molecules for radiopharmaceuticals development. Radiolabeled aptamers specific to the infectious agents, could give a significant contribution to the infection diagnosis by scintigraphy. In this study, aptamers selected to S. aureus were labeled with 99mTc and used for the bacteria identification in vitro and in vivo. The aptamers labeled with 32P and incubated in vitro with S. aureus cells showed high affinity for the bacterial cells when compared with the library of oligonucleotides with random sequences used as control. The aptamers labeled with 99mTc also showed affinity for S. aureus cells when compared with the library, but unspecific binding was also verified. The 99mTc labelled aptamers were stable in 0.9% saline, plasma of Swiss mice and in excess of cysteine. The in vivo biodistribution studies using Swiss mice with intramuscular infection in the right thigh showed that the aptamers labeled with

  1. SDS interferes with SaeS signaling of Staphylococcus aureus independently of SaePQ.

    Directory of Open Access Journals (Sweden)

    Phuti E Makgotlho

    Full Text Available The Staphylococcus aureus regulatory saePQRS system controls the expression of numerous virulence factors, including extracellular adherence protein (Eap, which amongst others facilitates invasion of host cells. The saePQRS operon codes for 4 proteins: the histidine kinase SaeS, the response regulator SaeR, the lipoprotein SaeP and the transmembrane protein SaeQ. S. aureus strain Newman has a single amino acid substitution in the transmembrane domain of SaeS (L18P which results in constitutive kinase activity. SDS was shown to be one of the signals interfering with SaeS activity leading to inhibition of the sae target gene eap in strains with SaeS(L but causing activation in strains containing SaeS(P. Here, we analyzed the possible involvement of the SaeP protein and saePQ region in SDS-mediated sae/eap expression. We found that SaePQ is not needed for SDS-mediated SaeS signaling. Furthermore, we could show that SaeS activity is closely linked to the expression of Eap and the capacity to invade host cells in a number of clinical isolates. This suggests that SaeS activity might be directly modulated by structurally non-complex environmental signals, as SDS, which possibly altering its kinase/phosphatase activity.

  2. Expression of arthritis-causing HLA-B27 on Hela cells promotes induction of c-fos in response to in vitro invasion by Salmonella typhimurium.

    OpenAIRE

    Ikawa, T; Ikeda, M; Yamaguchi, A; Tsai, W.C.; Tamura, N; Seta, N; Trucksess, M; Raybourne, R B; Yu, D T

    1998-01-01

    HLA-B27 confers a very strong genetic predisposition to development of a reactive arthritis after infection by bacteria such as Salmonella typhimurium. This study examines the role of HLA-B27 in the initiation of the earliest host activities after exposure to Salmonella, namely activation of the immediate early genes in the epithelial cells. Our major finding is that in Hela cells, the expression of c-fos was induced by Salmonella invasion only when the cells expressed the transfected HLA-B27...

  3. Infertility as a Consequence of Spermagglutinating Staphylococcus aureus Colonization in Genital Tract of Female Mice

    OpenAIRE

    Siftjit Kaur; Vijay Prabha

    2012-01-01

    Various studies have shown Staphylococcus aureus to be one of the most prevalent organism in male and female genital tract but most practitioners dismiss it as mere contamination which is assumed to be of no significance. However, it is now suggested that the presence of this organism should not be ignored, as incubation of spermatozoa with S. aureus results in reduced sperm motility. Although S. aureus has been reported to cause immobilization of spermatozoa, however, its role in infertility...

  4. A rare case of acute epiglottitis due to Staphylococcus aureus in an adult

    Directory of Open Access Journals (Sweden)

    Clare Harris

    2012-01-01

    Full Text Available Epiglottitis has been mainly associated with childhood infection with Haemophilis influenzae type B but cases of adult epiglottitis are increasing. We report here a case of adult epiglottitis and present evidence that it was caused by S. aureus. A 48-year old patient with clinical symptoms of epiglottitis grew Staphylococcus aureus in pure culture from an epiglottal swab. Staphylococcus aureus should be considered as a potential pathogen in adult epiglottitis.

  5. Methicillin-Resistant Staphylococcus aureus nosocomial infection trends in Hospital universiti sains Malasia during 2002-2007

    International Nuclear Information System (INIS)

    Methicillin-resistant staphylococcus aureus (MRSA) is a major nosocomial pathogen that causes severe morbidity and mortality in many hospitals worldwide.The aim of the present study was to assess the burden of MRSA nosocomial infection,its association with factors of interest, and its antimicrobial susceptibility.This was a retrospective analysis of a database of all s aureus that were cultured from patients admitted to the defferent wards of hospital universiti sains malasia(HUSM) over a aperiod of 6 years.The MRSA infections rate was 10.0 Per 1000 hospital admissions.The incidence density rate of MRSA infections during the study period was 1.8 per 1000 patient-days,with annual rates ranging from 0.95 to 3.47 per 1000 patients-days.Duration of hospitalization,previous antibiotic use,and bedside invasive proceures of MRSa infections were found in orthopedic wards (25.3%) followed by surgical wards (18.2%) amd omtensive care units(ICU) (16.4%).All MRSA isolates were resistant to erythromycin (98.0%),co-trimoxazole (94.0%)and gentamicin (92.0%)clindamycin was the best antibiotic with only 6% resistance.All MRSA isolates were sensitive to vancomycin.The rate of the noscomial MRSA infection per 1000 admissions was higher than that in other studies.The three factors associated most signaficantly with acquired MRSA infections included duration of hospitalization,antibiotic use,and bedside invasive procedures.This study confirmed that vancomycin-resistant s aureus has not yet been established in HUSM (Author).

  6. Study on hospital-acquired infections caused by invasive yeast in cancer patients%肿瘤患者医院内侵袭性酵母菌感染的研究

    Institute of Scientific and Technical Information of China (English)

    李丁; 张文芳; 郑珊; 张鹏

    2010-01-01

    Objective To investigate the clinical distribution and drug-susceptibility characteristics of yeast speeies in tumor patients with invasive yeast infections in order to provide the gist for clinical therapy.Methods The medical records of 70 tumor patients with invasive yeast infections from January 2006 to December 2008 were collected.retrospectively.The relationship between different tumor types and invasive yeast infections was analyzed.The clinical distribution and drug-susceptibility characteristics of 70 isolates of yeast were investigated.Results The sites of invasive yeast infections were abdominal(32 cases),blood(18 cases),biliary(9 cases),central nervous system(6 cases)and chest infection(5 cases).respectively.The most common species causing the above infections was Candida albicans(34 isolates,48.6%).The mortality of invasive yeast infection was 15.7%.The main types of tumor in 70 patients with invasive yeast infections were pancreatic carcinoma(12 cases),stomach carcinoma(11 cases)and hepatocellular carcinoma(7 cases).No relationship was found between tumor types and yeast infections with different species(P=0.804,P>0.05).There were 18 patients with tumor metastasis.Among them.9 patients had yeast bloodstream infections and 6 with yeast abdominal infections.Yeast bloodstream infections were more likely to be found in patients with tumor metastasis(χ~2=5.357,P0.05).18例肿瘤远处脏器转移的患者中发生酵母菌性血流感染者9例、腹腔酵母菌感染者6例肿瘤转移患者更易发生酵母菌性血流感染(χ~2=5.357,P<0.05).70株酵母菌对三唑类均敏感,但其中6株念珠菌及2株罗伦特隐球菌对两性霉素B的MIC值为2μg/ml.结论 应警惕肿瘤转移患者发生酵母菌感染,三唑类药物对酵母菌保持较高的抗菌活性.

  7. [Consensus document for the treatment of bacteremia and endocarditis caused by methicillin-resistent Staphylococcus aureus. Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica].

    Science.gov (United States)

    Gudiol, Francisco; Aguado, José María; Pascual, Alvaro; Pujol, Miquel; Almirante, Benito; Miró, José María; Cercenado, Emilia; Domínguez, María de Los Angeles; Soriano, Alex; Rodríguez-Baño, Jesús; Vallés, Jordi; Palomar, Mercedes; Tornos, Pilar; Bouza, Emilio

    2009-02-01

    Bacteremia and endocarditis due to methicillin-resistant Staphylococcus aureus (MRSA) are prevalent and clinically important. The rise in MRSA bacteremia and endocarditis is related with the increasing use of venous catheters and other vascular procedures. Glycopeptides have been the reference drugs for treating these infections. Unfortunately their activity is not completely satisfactory, particularly against MRSA strains with MICs > 1 microg/mL. The development of new antibiotics, such as linezolid and daptomycin, and the promise of future compounds (dalvabancin, ceftobiprole and telavancin) may change the expectatives in this field.The principal aim of this consensus document was to formulate several recommendations to improve the outcome of MRSA bacteremia and endocarditis, based on the latest reported scientific evidence. This document specifically analyzes the approach for three clinical situations: venous catheter-related bacteremia, persistent bacteremia, and infective endocarditis due to MRSA.

  8. Where does a Staphylococcus aureus vaccine stand?

    Science.gov (United States)

    Fowler, V G; Proctor, R A

    2014-05-01

    In this review, we examine the current status of Staphylococcus aureus vaccine development and the prospects for future vaccines. Examination of the clinical trials to date show that murine models have not predicted success in humans for active or passive immunization. A key factor in the failure to develop a vaccine to prevent S. aureus infections comes from our relatively limited knowledge of human protective immunity. More recent reports on the elements of the human immune response to staphylococci are analysed. In addition, there is some controversy concerning the role of antibodies for protecting humans, and these data are reviewed. From a review of the current state of understanding of staphylococcal immunity, a working model is proposed. Some new work has provided some initial candidate biomarker(s) to predict outcomes of invasive infections and to predict the efficacy of antibiotic therapy in humans. We conclude by looking to the future through the perspective of lessons gleaned from the clinical vaccine trials. PMID:24476315

  9. The role of staphylothrombin-mediated fibrin deposition in catheter-related Staphylococcus aureus infections.

    Science.gov (United States)

    Vanassche, Thomas; Peetermans, Marijke; Van Aelst, Lucas N L; Peetermans, Willy E; Verhaegen, Jan; Missiakas, Dominique M; Schneewind, Olaf; Hoylaerts, Marc F; Verhamme, Peter

    2013-07-01

    Staphylococcus aureus (S. aureus) is a frequent cause of catheter-related infections. S. aureus secretes the coagulases staphylocoagulase and von Willebrand factor-binding protein, both of which form a staphylothrombin complex upon binding to prothrombin. Although fibrinogen and fibrin facilitate the adhesion of S. aureus to catheters, the contribution of staphylothrombin-mediated fibrin has not been examined. In this study, we use a S. aureus mutant lacking both coagulases (Δcoa/vwb) and dabigatran, a pharmacological inhibitor of both staphylothrombin and thrombin, to address this question. Genetic absence or chemical inhibition of pathogen-driven coagulation reduced both fibrin deposition and the retention of S. aureus on catheters in vitro. In a mouse model of jugular vein catheter infection, dabigatran reduced bacterial load on jugular vein catheters, as well as metastatic kidney infection. Importantly, inhibition of staphylothrombin improved the efficacy of vancomycin treatment both in vitro and in the mouse model. PMID:23532100

  10. Molecular Characterization of Staphylococcus aureus Isolates Transmitted between Patients with Buruli Ulcer.

    Directory of Open Access Journals (Sweden)

    Nana Ama Amissah

    Full Text Available Buruli ulcer (BU is a skin infection caused by Mycobacterium ulcerans. The wounds of most BU patients are colonized with different microorganisms, including Staphylococcus aureus.This study investigated possible patient-to-patient transmission events of S. aureus during wound care in a health care center. S. aureus isolates from different BU patients with overlapping visits to the clinic were whole-genome sequenced and analyzed by a gene-by-gene approach using SeqSphere(+ software. In addition, sequence data were screened for the presence of genes that conferred antibiotic resistance.SeqSphere(+ analysis of whole-genome sequence data confirmed transmission of methicillin resistant S. aureus (MRSA and methicillin susceptible S. aureus among patients that took place during wound care. Interestingly, our sequence data show that the investigated MRSA isolates carry a novel allele of the fexB gene conferring chloramphenicol resistance, which had thus far not been observed in S. aureus.

  11. Brain infection following experimental Staphylococcus aureus sepsis in pigs

    DEFF Research Database (Denmark)

    Astrup, Lærke Boye; Iburg, Tine Moesgaard; Nielsen, Ole Lerberg;

    2010-01-01

    Introduction: Sepsis is a major problem in humans and both the incidence and mortality is increasing. Multiple microabcesses can be found in the brain of septic patients. Staphylococcus aureus is one of the most common causes of sepsis and brain abscesses. S. aureus is also a frequent cause...... pigs were kept as controls. The pigs were euthanized in groups of four at either 6, 12, 24 or 48 h post infection. The brain was collected from all the animals and examined histologically. Results: All the inoculated pigs developed sepsis and 7 out of 12 animals had microabscesses in the prosencephalon...

  12. Multilocus Sequence Typing And Antibiotic Resistance Of Staphylococcus Aureus Isolated From The Brazilian Dairy Industry

    DEFF Research Database (Denmark)

    Dittmann, Karen Kiesbye; Chaul, Luiza; Lee, Sarah;

    2015-01-01

    Staphylococcus aureus is a common cause of food poisoning due to enterotoxin production. This is particularly an issue in the dairy industry, where S. aureus can contaminate the product e.g. from raw milk or the handlers. In Brazil, soft cheese is mainly produced in small dairy plants where good...

  13. Community-Acquired Methicillin-Resistant "Staphylococcus aureus": Considerations for School Nurses

    Science.gov (United States)

    Alex, Aniltta; Letizia, MariJo

    2007-01-01

    Methicillin-resistant "Staphylococcus aureus" (MRSA) is a disease-causing organism that has been present in hospital settings since the 1960s. However, a genetically distinct strain of MRSA, called community-acquired methicillin-resistant "Staphylococcus aureus" (CA-MRSA), has emerged in recent years in community settings among healthy…

  14. Host adaptation of bovine Staphylococcus aureus seems associated with bacteriological cure after lactational antimicrobial treatment

    NARCIS (Netherlands)

    Borne, van den B.H.P.; Nielen, M.; Schaik, van G.; Melchior, M.B.; Lam, T.J.G.M.; Zadoks, R.N.

    2010-01-01

    Staphylococcus aureus causes a wide range of diseases in multiple species. Some sequence types (ST) are observed in a variety of hosts, whereas other strains are mainly associated with bovine mastitis, suggesting host adaptation. We propose that host adaptation of Staph. aureus may influence bacteri

  15. AVALIAÇÃO FENOTÍPICA E GENOTÍPICA DO PERFIL DE RESISTÊNCIA DE AMOSTRAS DE Staphylococcus aureus ISOLADAS DE CULTURAS CLÍNICAS E DE VIGILÂNCIA DE UM HOSPITAL DE ENSINO BRASILEIRO

    Directory of Open Access Journals (Sweden)

    Lívia Cafundó Almeida

    2012-12-01

    Full Text Available Staphylococcus aureus can cause a variety of infections, especially nosocomial. Its importance lies in the combination of virulence, invasiveness and antibiotic resistance constituting therapeutic challenges. This study aimed to assess the genotype and phenotypic resistance profiles of samples of S. aureus isolated from hospitalized patients in a Brazilian teaching hospital. We evaluated 1078 samples obtained from surveillance cultures and clinical S. aureus in hospitalized patients. To assess the phenotypic resistance profile was used disk diffusion method according to CLSI criteria, 2011. For the determination of genotypic resistance was the presence of the mecA gene by polymerase chain reaction - PCR. Of the 1078 samples tested phenotypically, it was observed that 75.1% of the samples were Methicillin Resistant Staphylococcus aureus (MRSA, and of these, 98.4% were resistant to oxacillin and 100%, cefoxitin. To determine genotype was performed for the PCR amplification of the mecA gene. Of the 443 samples tested for the mecA 336 samples were positive (75.8%. Of these samples, 85.7% showed resistance phenotype oxacillin and cefoxitin 88.4%. Due to the high rate of MRSA, concludes the need for investment in research, rational use of antimicrobials and creation of reference laboratories for verification of antimicrobial resistance.

  16. A combination of positive dielectrophoresis driven on-line enrichment and aptamer-fluorescent silica nanoparticle label for rapid and sensitive detection of Staphylococcus aureus.

    Science.gov (United States)

    Shangguan, Jingfang; Li, Yuhong; He, Dinggeng; He, Xiaoxiao; Wang, Kemin; Zou, Zhen; Shi, Hui

    2015-07-01

    Staphylococcus aureus (S. aureus) is an important human pathogen that causes several diseases ranging from superficial skin infections to life-threatening diseases. Here, a method combining positive dielectrophoresis (pDEP) driven on-line enrichment and aptamer-fluorescent silica nanoparticle label has been developed for the rapid and sensitive detection of S. aureus in microfluidic channels. An aptamer, having high affinity to S. aureus, is used as the molecular recognition tool and immobilized onto chloropropyl functionalized fluorescent silica nanoparticles through a click chemistry approach to obtain S. aureus aptamer-nanoparticle bioconjugates (Apt(S.aureus)/FNPs). The pDEP driven on-line enrichment technology was used for accumulating the Apt(S.aureus)/FNP labeled S. aureus. After incubating with S. aureus, the mixture of Apt(S.aureus)/FNP labeled S. aureus and Apt(S.aureus)/FNPs was directly introduced into the pDEP-based microfluidic system. By applying an AC voltage in a pDEP frequency region, the Apt(S.aureus)/FNP labelled S. aureus moved to the electrodes and accumulated in the electrode gap, while the free Apt(S.aureus)/FNPs flowed away. The signal that came from the Apt(S.aureus)/FNP labelled S. aureus in the focused detection areas was then detected. Profiting from the specificity of aptamer, signal amplification of FNP label and pDEP on-line enrichment, this assay can detect as low as 93 and 270 cfu mL(-1)S. aureus in deionized water and spiked water samples, respectively, with higher sensitivities than our previously reported Apt(S.aureus)/FNP based flow cytometry. Moreover, without the need for separation and washing steps usually required for FNP label involved bioassays, the total assay time including sample pretreatment was within 2 h.

  17. Surveillance of invasive diseases caused by Streptococcus pneumoniae in Italy: evolution of serotypes and antibiotic resistance in different age groups before and after implementation of PCV7

    Directory of Open Access Journals (Sweden)

    Fabio D’Ambrosio

    2013-04-01

    Full Text Available Background: PCV7 has been available in Italy since 2001, however only in 2005 national recommendations were issued and vaccination was implemented with different modalities by the Regions. Objectives: Aim of this study was to describe changes in serotype distribution and antibiotic susceptibility of S. pneumoniae from invasive pneumococcal diseases (IPD in the last decade. Study Design: S. pneumoniae isolates from IPD, collected through a national surveillance system, were serotyped and antibiotic susceptibility was determined by E-test. Data were analyzed according to age groups (5 years, >5-64 years, 65 years and to 3 time periods: prior, during and after PCV7 implementation (2001- 2003, 2006-2008 and 2009-2011. Results: The percentage of PCV7 serotypes (vaccine serotypes, VS decreased over the years not only in children (from 60% to 26% but also in the other age groups. Penicillin resistance was rather low in 2001-2003 (7-12%, but peaked in children in 2006-2008 (24%, and decreased in 2009-2011, while erythromycin resistance slightly decreased over the 3 periods. Conclusions: PCV7 use has largely impacted the epidemiology of S. pneumoniae in Italy, with a decrease in VS in all age groups.The impact of PCV 13, available in Italy since the end of 2010, requires future evaluations.

  18. Community-based outbreaks in vulnerable populations of invasive infections caused by Streptococcus pneumoniae serotypes 5 and 8 in Calgary, Canada.

    Directory of Open Access Journals (Sweden)

    Otto G Vanderkooi

    Full Text Available BACKGROUND: Outbreaks of invasive pneumococcal disease (IPD typically occur within institutions. Beginning in 2005, we detected an increase in serotype (ST 5 and ST8 IPD cases, predominantly in homeless persons living in an open community. METHODOLOGY/PRINCIPAL FINDINGS: CASPER (Calgary Area S. pneumoniae Epidemiology Research surveillance study of all IPD (sterile site isolates in our region (pop ~1,100,000. Interviews and chart reviews of all cases and all isolates phenotypically analyzed and selected isolated tested by multi-locus sequence typing (MLST. CONCLUSIONS/SIGNIFICANCE: During 2005-2007, 162 cases of ST5 IPD and 45 cases of ST8 IPD were identified. The isolates demonstrated phenotypic and genotypic clonality. The ST5 isolates were sequence type (ST 289 and demonstrated intermediate susceptibility to TMP-SMX. The ST8 isolates were predominantly ST1268, with a susceptible antimicrobial susceptibility profile. Individuals with ST5 IPD were more likely to be middle aged (OR 2.6, homeless (OR 4.4, using illicit drugs(OR 4.8, and asthmatic(OR 2.6. Those with ST8 were more likely to be male (OR 4.4, homeless (OR 2.6, aboriginal (OR7.3, and a current smoker (OR 2.5. Overlapping outbreaks of ST5 and ST8 IPD occurred in an open community in Calgary, Canada and homelessness was a predominant risk factor. Homelessness represents a unique community in which pneumococcal outbreaks can occur.

  19. [Guidelines for prevention, control and treatment of infections caused by methicillin-resistant Staphylococcus aureus (MRSA): changes and updates of chapter 7.0: treatment of patients with MRSA infection].

    Science.gov (United States)

    Kalenić, Smilja; Pal, Marina Payerl; Palcevski, Vera Vlahović; Horvatić, Jasminka; Mestrović, Tomislav; Barsić, Bruno; Stamenić, Valerija; Burcar, Ivan; Korusić, Andelko; Vucić, Marinko; Civljak, Rok; Stancić, Marin; Budimir, Ana

    2010-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is an important pathogen throughout the world, and as well in Croatia. Therefore it was decided to develop guidelines with the aim to reduce the number of patients infected/colonized with MRSA in healthcare facilities and in nursing homes in Croatia, consequently reducing MRSA-related morbidity and mortality. An interdisciplinary team of experts developed these guidelines using existing international guidelines from different countries, and literature reviews about prevention, control, treatment and laboratory diagnosis of MRSA infections. Grades of evidence for specific recommendations were determined using CDC/HICPAC grading system. Categorization is based on existing data, theoretical basis, applicability and economic impact. After a broad discussion in different professional societies, Guidelines were accepted. In the meantime, several new possibilities appeared in the treatment of patients with MRSA infections in Croatia, so the Chapter 7.0 Treatment of patients with MRSA infections is changed and updated according to the new treatment possibilities. The rest of the Guidelines was not changed. PMID:21294322

  20. Linezolid resistant Staphylococcus aureus

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    Pavani Gandham

    2014-08-01

    Full Text Available Linezolid is the only antibiotic available as an oral formulation for resistant staphylococcal infections. It is effective in skin and soft tissue infections, nosocomial pneumonias including VAP, infective endocarditis and MRSA meningitis. It is also effective in the eradication of both nasal and throat colonization of MRSA. Its high bioavailability and post antibiotic effect, ease of switching to oral therapy during its use and the fact that it can be used in patients of all ages, also in patients with liver disease and poor kidney function and its increased effectiveness over glycopeptides makes this drug a precious drug in the treatment of resistant staphylococcal infections. Linezolid resistance in staphylococcus is defined as a linezolid MIC of and #8805;8 mg/L. Reported Linezolid resistance in India and elsewhere is 2-20%. There is clonal dissemination of Linezolid Resistant Staphylococcus aureus (LRSA within or across health care settings which demands continuous surveillance to determine the emergent risk of resistance strains and to establish guidelines for appropriate use. Clinical laboratories should confirm any LRSA preferably by a second method, prior to using linezolid for serious infections. Effective surveillance, more judicious use of this antibiotic, avoiding linezolid usage for empiric therapy in hospital acquired staphylococcus infections, optimization of the pharmacological parameters of the antibiotics in specific clinical situation, decreasing bacterial load by timely surgical debridement or drainage of collections, use of combination therapies would prevent the emergence of resistance to linezolid in staphylococcus aureus. [Int J Res Med Sci 2014; 2(4.000: 1253-1256

  1. Invasive species

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a summary of management activities and research related to invasive species on Neal Smith National Wildlife Refuge between 1992 and 2009. As part of the...

  2. Staphylococcus aureus small colony variants in diabetic foot infections

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    Estrella Cervantes-García

    2015-03-01

    Full Text Available Background: Staphylococcus aureus (S. aureus is one of the major pathogens causing chronic infections. The ability of S. aureus to acquire resistance to a diverse range of antimicrobial compounds results in limited treatment options, particularly in methicillin-resistant S. aureus (MRSA. A mechanism by which S. aureus develops reduced susceptibility to antimicrobials is through the formation of small colony variants (SCVs. Infections by SCVs of S. aureus are an upcoming problem due to difficulties in laboratory diagnosis and resistance to antimicrobial therapy. Methods: A prospective study was performed on 120 patients diagnosed with both type 2 diabetes mellitus and infected diabetic foot ulcers. The study was carried out from July 2012 to December 2013 in Hospital General de Mexico. The samples were cultured in blood agar, mannitol salt agar, and MacConkey agar media, and incubated at 37°C in aerobic conditions. Results: We describe the first known cases of diabetic foot infections caused by MRSA-SCVs in patients diagnosed with type 2 diabetes mellitus and infected diabetic foot ulcers. In all of our cases, the patients had not received any form of gentamicin therapy. Conclusions: The antibiotic therapy commonly used in diabetic patients with infected diabetic foot ulcers fails in the case of MRSA-SCVs because the intracellular location protects S. aureus-SCVs from the host's defenses and also helps them resist antibiotics. The cases studied in this article add to the spectrum of persistent and relapsing infections attributed to MRSA-SCVs and emphasizes that these variants may also play a relevant role in diabetic foot infections.

  3. SAMMD: Staphylococcus aureus Microarray Meta-Database

    Directory of Open Access Journals (Sweden)

    Elasri Mohamed O

    2007-10-01

    Full Text Available Abstract Background Staphylococcus aureus is an important human pathogen, causing a wide variety of diseases ranging from superficial skin infections to severe life threatening infections. S. aureus is one of the leading causes of nosocomial infections. Its ability to resist multiple antibiotics poses a growing public health problem. In order to understand the mechanism of pathogenesis of S. aureus, several global expression profiles have been developed. These transcriptional profiles included regulatory mutants of S. aureus and growth of wild type under different growth conditions. The abundance of these profiles has generated a large amount of data without a uniform annotation system to comprehensively examine them. We report the development of the Staphylococcus aureus Microarray meta-database (SAMMD which includes data from all the published transcriptional profiles. SAMMD is a web-accessible database that helps users to perform a variety of analysis against and within the existing transcriptional profiles. Description SAMMD is a relational database that uses MySQL as the back end and PHP/JavaScript/DHTML as the front end. The database is normalized and consists of five tables, which holds information about gene annotations, regulated gene lists, experimental details, references, and other details. SAMMD data is collected from the peer-reviewed published articles. Data extraction and conversion was done using perl scripts while data entry was done through phpMyAdmin tool. The database is accessible via a web interface that contains several features such as a simple search by ORF ID, gene name, gene product name, advanced search using gene lists, comparing among datasets, browsing, downloading, statistics, and help. The database is licensed under General Public License (GPL. Conclusion SAMMD is hosted and available at http://www.bioinformatics.org/sammd/. Currently there are over 9500 entries for regulated genes, from 67 microarray

  4. Biofilm formation and genotyping of Staphylococcus aureus bovine mastitis isolates: Evidence for lack of penicillin-resistance in Agr-type II strains

    NARCIS (Netherlands)

    Melchior, M.B.; Osch, M.H.J.; Graat, R.; Duijkeren, van E.; Mevius, D.J.; Nielen, M.; Gaastra, W.; Fink, J.

    2009-01-01

    The increasing evidence for a role of biofilm formation in bovine mastitis caused by Staphylococcus aureus led to further investigations on biofilm formation by S. aureus isolates from mastitis in two growth media (TSBg and bovine milk serum). The ability of 99 S. aureus strains that were recently i

  5. Biofilm formation and genotyping of Staphylococcus aureus bovine mastitis isolates: evidence for lack of penicillin-resistance in Agr-type II strains.

    NARCIS (Netherlands)

    Melchior, M.B.; van Osch, M.H.J.; Graat, R.M.; van Duijkeren, E.; Mevius, D.J.; Nielen, M.; Gaastra, W.; Fink-Gremmels, J.

    2009-01-01

    The increasing evidence for a role of biofilm formation in bovine mastitis caused by Staphylococcus aureus led to further investigations on biofilm formation by S. aureus isolates from mastitis in two growth media (TSBg and bovine milk serum). The ability of 99 S. aureus strains that were recently i

  6. Biological invasion of phytophagous insects and spin-off for italian landscape: two cases caused by rhynchophorus ferrugineus and matsucoccus feytaudi

    Directory of Open Access Journals (Sweden)

    Stella Agostini

    2011-02-01

    Full Text Available Trees mark the environment, colours and structure of Italian landscapes. In the last decades they are often infested of attack by several infestions which is changing the context perception. Paper analyses the effect on the landscape caused in the palms (Phoenix canariensis attacked by the Rhynchophorus ferrugineus and in the Pinus pinaster by Matsucoccus feytaudi Ducasse.

  7. Biological invasion of phytophagous insects and spin-off for italian landscape: two cases caused by rhynchophorus ferrugineus and matsucoccus feytaudi

    Directory of Open Access Journals (Sweden)

    Santi Longo

    Full Text Available Trees mark the environment, colours and structure of Italian landscapes. In the last decades they are often infested of attack by several infestions which is changing the context perception. Paper analyses the effect on the landscape caused in the palms (Phoenix canariensis attacked by the Rhynchophorus ferrugineus and in the Pinus pinaster by Matsucoccus feytaudi Ducasse.

  8. Distinctive Cytokines as Biomarkers Predicting Fatal Outcome of Severe Staphylococcus aureus Bacteremia in Mice

    NARCIS (Netherlands)

    S. van den Berg (Sanne); J.D. Laman (Jon); L. Boon (Louis); M.T. ten Kate (Marian); G.J. de Knegt (Gerjo); R.M. Verdijk (Robert); H.A. Verbrugh (Henri); J.L. Nouwen (Jan); I.A.J.M. Bakker-Woudenberg (Irma)

    2013-01-01

    textabstractInvasive Staphylococcus aureus infections are frequently associated with bacteraemia. To support clinical decisions on antibiotic therapy, there is an urgent need for reliable markers as predictors of infection outcome. In the present study in mice, bacteraemia was established by intrave

  9. Population structure and antimicrobial profile of Staphylococcus aureus strains associated with bovine mastitis in China.

    Science.gov (United States)

    Zhang, Lili; Li, Yuchen; Bao, Hongduo; Wei, Ruicheng; Zhou, Yan; Zhang, Hui; Wang, Ran

    2016-08-01

    Staphylococcus aureus is a significant bacterial pathogen associated with bovine mastitis. The aim of the present study was to investigate and characterize of S. aureus strains isolated from the milk of cows suffering from mastitis in the mid-east of China. Among the 200 milk samples analyzed, 58 were positive for S. aureus, of these isolates, 11 isolates were methicillin-resistant Staphylococcus aureus (MRSA). All of the 58 S. aureus strains were classified in agr group I, while seven different sequence type (ST) patterns were identified and among them the most common was ST630 followed by ST188. All of the S. aureus isolates belonging to ST630 were resistant to more than four antimicrobials, and 22.2% of isolates belonging to ST188 were resistant to eight antimicrobials. Interestingly, while strong biofilm producers demonstrated higher resistance to multiple antimicrobials, they exhibited lower intracellular survival rates. The results of this study illustrated the distribution, antimicrobial susceptibility profiles, genotype, and the ability of biofilm production and mammary epithelial cells invasion of these S. aureus isolates. This study can provide the basis for the development of a disease prevention program in dairy farms to reduce the potential risk in both animal and human health.

  10. Population structure and antimicrobial profile of Staphylococcus aureus strains associated with bovine mastitis in China.

    Science.gov (United States)

    Zhang, Lili; Li, Yuchen; Bao, Hongduo; Wei, Ruicheng; Zhou, Yan; Zhang, Hui; Wang, Ran

    2016-08-01

    Staphylococcus aureus is a significant bacterial pathogen associated with bovine mastitis. The aim of the present study was to investigate and characterize of S. aureus strains isolated from the milk of cows suffering from mastitis in the mid-east of China. Among the 200 milk samples analyzed, 58 were positive for S. aureus, of these isolates, 11 isolates were methicillin-resistant Staphylococcus aureus (MRSA). All of the 58 S. aureus strains were classified in agr group I, while seven different sequence type (ST) patterns were identified and among them the most common was ST630 followed by ST188. All of the S. aureus isolates belonging to ST630 were resistant to more than four antimicrobials, and 22.2% of isolates belonging to ST188 were resistant to eight antimicrobials. Interestingly, while strong biofilm producers demonstrated higher resistance to multiple antimicrobials, they exhibited lower intracellular survival rates. The results of this study illustrated the distribution, antimicrobial susceptibility profiles, genotype, and the ability of biofilm production and mammary epithelial cells invasion of these S. aureus isolates. This study can provide the basis for the development of a disease prevention program in dairy farms to reduce the potential risk in both animal and human health. PMID:27265679

  11. Efficacy of norvancomycin in treatment of ventilator-associated pneumonia caused by methicillin-resistant Staphylococcus aureus in ICU%去甲万古霉素对ICU呼吸机相关性肺炎MRSA的治疗作用

    Institute of Scientific and Technical Information of China (English)

    鲍滨

    2011-01-01

    OBJECTIVE To analyze the pathogenic characteristics of intensive care unit ventilator-associated pneumonia (VAP) and the effect of vancomycin treatment of methicillin-resistant Staphylococcus aureus infection. METHODS A retrospective analysis of 235 cases medical data of VAP was performed by VITEK-32 system identificat the type of pathogenic bacteria. By disk diffusion method detection of methicillin resistant Staphylococcus aureus (MRSA), MRSA vancomycin or vancomycin therapy for patients with infected with MRSA, observed and compared the clinical efficacy and bacteriological efficacy of two drugs. RESULTS The isolated 235 pathogens, among Gram-negative bacteria 177, accounting for 75. 32%, Gram-positive "bacteria 53 strains, accounting for 22. 55%, fungi 5 strains, accounting for 2. 13%, The most distribution 3 pathogens were Pseudomonas aerugino-sa , Klebsiella pneumoniae and S. Aureus, accounting for 30. 21% , 22. 13% and 21. 70%. 43 strains, MRSA the detection rate was 84. 31%,43 MRSA to vancomycin therapy in patients with 23 cases, 20 cases of vancomycin treatment. Norvancomycin group 5 patients died, mortality rate was 21. 74%, total effective rate was 60. 87%, vancomycin group 4 died, the mortality rate was 20. 00%, total effective rate was 60. 00%, Bacteriological efficacy to vancomycin showed vancomycin group and the clearance rate was 88. 89% and 87. 50%. CONCLUSION The patients with ventilator-associated pneumonia MRSA in ICU infection rate is higher, vancomycin efficacy against MRSA and vancomycin a. The efficacy of Vancomycin treatment for MRSA is almost the same as vancomycin.%目的 分析ICU呼吸机相关性肺炎(VAP)的病原菌特点及去甲万古霉素对耐甲氧西林金黄色葡萄球菌(MRSA)的治疗作用.方法 回顾性分析235份VAP的病历资料,采用VITEK-32系统鉴定病原菌种类,用纸片扩散法检测MRSA,对感染MRSA的患者用去甲万古霉素或万古霉素治疗,观察并比较两种药物的临床

  12. Methicillin-resistant Staphylococcus aureus laryngitis.

    Science.gov (United States)

    Liakos, Tracey; Kaye, Keith; Rubin, Adam D

    2010-09-01

    Infections due to methicillin-resistant Staphylococcus aureus (MRSA) have become more prevalent, in part because of the emergence and spread of community-acquired MRSA. This trend is particularly concerning because of the significant rates of morbidity and mortality associated with MRSA infections, and because MRSA strains are often resistant to many classes of antibiotics. Reports of infections of the head and neck, including wound infections, cellulitis, sinusitis, otitis media, and otitis externa, are well documented. However, to our knowledge, there have been no reports of bacterial laryngitis due to MRSA. We report the first published case of bacterial laryngitis caused by MRSA.

  13. Staphylococcus aureus triggered reactive arthritis.

    OpenAIRE

    Siam, A R; M. Hammoudeh

    1995-01-01

    OBJECTIVES--To report two patients who developed reactive arthritis in association with Staphylococcus aureus infection. METHODS--A review of the case notes of two patients. RESULTS--Two adult female patients have developed sterile arthritis in association with Staph aureus infection. The first patient has had two episodes of arthritis; the first followed olecranon bursitis, the second followed infection of a central venous catheter used for dialysis. The second patient developed sterile arth...

  14. Characterization of Haemolysin of Staphylococcus aureus Isolated from Food of Animal Origin

    Directory of Open Access Journals (Sweden)

    Dwi Ariyanti

    2015-11-01

    Full Text Available Staphylococcus aureus is an important pathogen bacteria causing food poisoning and various infection in animals and humans. Haemolysin is one of the virulence factors of Staphylococcus aureus. The aims of the research were to characterize haemolysins of Staphylococcus aureus isolated from various food of animal origin, phenotypic- and genotypically. In the present study, eleven Staphylococcus aureus isolated from various food of animal origins from traditional markets and supermarkets in Yogyakarta, Sidoarjo, Jakarta, and Bandung were characterized for haemolysin, pheno- and genotypically. Characterization of haemolysin phenotypically based on haemolysis pattern of Staphylococcus aureus on sheep blood agar plate. Genes encoding hemolysin were amplified with specific primers by using polymerase chain reaction (PCR technique. The results of the studies showed that Staphylococcus aureus on sheep blood agar plates revealed an alpha haemolysis pattern (18,18%, beta haemolysis (27,27% and gamma haemolysis (54,55%. Based on amplification of the gene encoding haemolysin of Staphylococcus aureus with specific primers showed hla genes (81,81%, and hla combined with hlb genes (18,18%. The amplification of gene hla and hlb had a single amplicon with a size of approximately 534 bp and 833 bp, respectively. The haemolysin characteristics of Staphylococcus aureus from various food of animal origin could be used as important information to control staphylococcal food poisoning.Keywords : Staphylococcus aureus, haemolysin, PCR, food of animal origins

  15. Genetic Diversity of Staphylococcus aureus in Buruli Ulcer

    NARCIS (Netherlands)

    Amissah, Nana Ama; Glasner, Corinna; Ablordey, Anthony; Tetteh, Caitlin S.; Kotey, Nana Konama; Prah, Isaac; van der Werf, Tjip; Rossen, John W.; van Dijl, Jan Maarten; Stienstra, Ymkje

    2015-01-01

    Background Buruli ulcer (BU) is a necrotizing skin disease caused by Mycobacterium ulcerans. Previous studies have shown that wounds of BU patients are colonized with M. ulcerans and several other microorganisms, including Staphylococcus aureus, which may interfere with wound healing. The present st

  16. Natural Population Dynamics and Carriage of Staphylococcus aureus

    NARCIS (Netherlands)

    D.C. Melles (Damian)

    2008-01-01

    textabstractStaphylococcus aureus is a major human pathogen capable of causing a wide range of infections, from relatively mild skin infections such as folliculitis and furunculosis to life-threatening conditions, including sepsis, deep abscesses, pneumonia, osteomyelitis, and infective endocarditis

  17. New insights into molecular typing methods for Staphylococcus aureus

    NARCIS (Netherlands)

    Ikawaty, R.

    2009-01-01

    Staphylococcus aureus (SA) remains a significant problem causing infections in both hospital and community settings. Methicillin-resistant SA (MRSA) continues to evolve and pose a great challenge through outbreaks and pandemic spread. Humans are no longer the only and the most important reservoir of

  18. Pathogenic Staphylococcus aureus Isolates from Postoperative Wounds of Hospitalized Patients

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    Smritikana Biswas

    2010-07-01

    Full Text Available Staphylococcus sp., gram positive pyogenic bacteria located on skin, nose etc, secretes toxin that causes toxic shock syndrome, abscess, food poisoning and other infectious diseases. This study was carried out to identify and characterize the type of Staphylococcus sp. bacteria especially Staphylococcus aureus in the pus from postoperative wounds of hospitalized patients. From pus samples collected from twenty-four patients from Kharagpur Hospital, Paschim Medinipur, West Bengal, twenty-eight bacterial isolates were obtained. Among them twenty-five (89.2% were appeared with golden yellow colonies which is usually formed by Staphylococcus aureus. Twenty-three (82.14% of the bacterial isolates were Gram positive. Among them twenty isolates (86.9% were further confirmed to be Staphylococcus aureus by their ability to produce Catalase enzyme (positive in Catalase test and Coagulase enzyme (positive in Coagulase Test. Eighteen (90.00% of these Staphylococcus aureus were found to liquefy gelatin (Gelatin hydrolysis test, were able to hydrolyze urea (Urea hydrolysis test and were also l positive in Mannitol Fermentation Test. But there was no growth found of these isolates on MacConkey Agar, while sixteen isolates (80.00% of Staphylococcus aureus were resistant to penicillin (50µg/ml. Moreover eighteen (90.00% Staphylococcus aureus isolates were able to elaborate Hemolysin (Hemolysis test on Blood Agar media. Hence the bacterial isolates obtained from pus of postoperative wounds were predominantly pathogenic Staphylococcus aureus. So it can be concluded that careful treatment and postoperative measures to be taken to avoid serious health problem that may often be life threatening.

  19. Species-Level Identification of Actinomyces Isolates Causing Invasive Infections: Multiyear Comparison of Vitek MS (Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry) to Partial Sequencing of the 16S rRNA Gene.

    Science.gov (United States)

    Lynch, T; Gregson, D; Church, D L

    2016-03-01

    Actinomyces species are uncommon but important causes of invasive infections. The ability of our regional clinical microbiology laboratory to report species-level identification of Actinomyces relied on molecular identification by partial sequencing of the 16S ribosomal gene prior to the implementation of the Vitek MS (matrix-assisted laser desorption ionization-time of flight mass spectrometry [MALDI-TOF MS]) system. We compared the use of the Vitek MS to that of 16S rRNA gene sequencing for reliable species-level identification of invasive infections caused by Actinomyces spp. because limited data had been published for this important genera. A total of 115 cases of Actinomyces spp., either alone or as part of a polymicrobial infection, were diagnosed between 2011 and 2014. Actinomyces spp. were considered the principal pathogen in bloodstream infections (n = 17, 15%), in skin and soft tissue abscesses (n = 25, 22%), and in pulmonary (n = 26, 23%), bone (n = 27, 23%), intraabdominal (n = 16, 14%), and central nervous system (n = 4, 3%) infections. Compared to sequencing and identification from the SmartGene Integrated Database Network System (IDNS), Vitek MS identified 47/115 (41%) isolates to the correct species and 10 (9%) isolates to the correct genus. However, the Vitek MS was unable to provide identification for 43 (37%) isolates while 15 (13%) had discordant results. Phylogenetic analyses of the 16S rRNA sequences demonstrate high diversity in recovered Actinomyces spp. and provide additional information to compare/confirm discordant identifications between MALDI-TOF and 16S rRNA gene sequences. This study highlights the diversity of clinically relevant Actinomyces spp. and provides an important typing comparison. Based on our analysis, 16S rRNA gene sequencing should be used to rapidly identify Actinomyces spp. until MALDI-TOF databases are optimized.

  20. Nonviable Staphylococcus aureus and its peptidoglycan stimulate macrophage recruitment, angiogenesis, fibroplasia, and collagen accumulation in wounded rats.

    Science.gov (United States)

    Kilcullen, J K; Ly, Q P; Chang, T H; Levenson, S M; Steinberg, J J

    1998-01-01

    We have previously shown that local application at the time of operation of Staphylococcus aureus, nonviable S. aureus, its cell wall, or S. aureus peptidoglycan accelerates wound healing. We hypothesized that this effect is due to both direct and indirect mechanisms, among which is an increase in the inflammatory response to wounding, resulting in an increase in macrophages, angiogenesis, and fibroblasts. Twenty-seven Sprague-Dawley male rats were anesthetized, and two 7-cm paravertebral skin incisions were made. Four polyvinyl alcohol sponges, two on each side, containing either 100 microliter of isotonic saline or 0.5 mg of nonviable S. aureus or S. aureus peptidoglycan in 100-microliter saline were implanted subcutaneously. Nonviable S. aureus or S. aureus peptidoglycan (860 microgram/cm incision) in 200-microliter saline were inoculated into the incisions at closure. The rats ate a commercial rat chow and drank tap water ad libitum throughout. After days 3 and 7 postwounding, rats were euthanized, and tissues were examined for immunohistochemical features of reparative tissue using ED-1, Factor VIII, and vimentin antibodies, markers for monocyte/macrophages, endothelial cells, and mesenchymal cells (including fibroblasts), respectively. Incisions treated with nonviable S. aureus or S. aureus peptidoglycan showed more macrophages along and deep in the wound tract 7 days postoperatively. Nonviable S. aureus or S. aureus peptidoglycan-treated sponges were surrounded and penetrated by much larger capsules of reparative tissue than saline-treated sponges at both 3 and 7 days. Neutrophil influx was much greater in nonviable S. aureus or S. aureus peptidoglycan-treated sponges, especially in central regions, and there were many more ED-1-stained macrophages in distinct geographic locations, specifically, the more peripheral-cortical areas. Some clustering of macrophages occurred around areas of invasion by reparative tissue into the surrounding subcutaneous fat and

  1. Staphylococcus aureus Bacteraemia

    Directory of Open Access Journals (Sweden)

    James Price

    2010-01-01

    Full Text Available Staphylococcus aureus bacteraemia (SAB is commonly complicated by metastatic infection or relapse after treatment. Objectives. The study aim was to determine the role of bacterial, host, and management factors in development of complicated SAB. Methods. A prospectively-conducted observational study gathered data on predisposition, management and outcome of 100 consecutive SAB cases. Antibiotic susceptibilities and genetic lineage of bacterial isolates were determined. Further clinical and microbiological data were gathered on two retrospective series from 1999–2000 (n=57 and 2004 (n=116. Results. In the prospective cases, 27% met our definition of complicated disease. Expressed as RR and 95% CI, complicated disease was associated with diabetes (1.58, 1.00–2.48, injecting-drug use (5.48, 0.88–33.49, community-onset of symptoms (1.4, 1.02–1.92, and symptom duration ≥48 hours prior to starting effective antibiotic therapy (2.10, 1.22–3.61. Uncomplicated disease was associated with the presence of a central line (0.69, 0.55–0.88 and prompt removal of a primary focus (0.71, 0.57–0.90. Neither methicillin resistance nor genetic lineage was associated with complicated disease, but methicillin resistance was associated with higher mortality. Conclusions. This study demonstrates that clinical rather than microbial factors are the major determinants of SAB outcome and underscores the importance of early treatment.

  2. Evaluation of aptamers labelled with {sup 99m}Tc for identification of Staphylococcus aureus bacteria; Avaliacao de aptameros marcados com {sup 99m}Tc para identificacao de focos infecciosos de Staphylococcus aureus

    Energy Technology Data Exchange (ETDEWEB)

    dos Santos, Sara Roberta

    2014-06-01

    Staphylococcus aureus is specie of great medical importance because it is often associated with many infections in humans. This bacterium can cause diseases ranging from simple infections to life-threatening infections such as endocarditis, pneumonia, meningitis, toxic shock syndrome, septicemia, osteomyelitis, among others. S. aureus is the most commonly agent found in infections of the skin and soft tissues, bone infections and bone prostheses. The difficulty in early detection of specific foci caused by bacteria has raised the need to search for new techniques for this purpose. Diagnosis by scintigraphy has advantages over other methods because it is able to identify damage tissues without the need of invasive procedures and is able to perform an early diagnosis even before anatomic changes. Thus, nuclear medicine could contribute to an accurate diagnosis of bacterial infections, since specific radiopharmaceuticals were developed. Aptamers are oligonucleotides that have high affinity and specificity for their molecular targets and are emerging as a new class of molecules for radiopharmaceuticals development. Radiolabeled aptamers specific to the infectious agents, could give a significant contribution to the infection diagnosis by scintigraphy. In this study, aptamers selected to S. aureus were labeled with {sup 99m}Tc and used for the bacteria identification in vitro and in vivo. The aptamers labeled with {sup 32}P and incubated in vitro with S. aureus cells showed high affinity for the bacterial cells when compared with the library of oligonucleotides with random sequences used as control. The aptamers labeled with {sup 99m}Tc also showed affinity for S. aureus cells when compared with the library, but unspecific binding was also verified. The {sup 99m}Tc labelled aptamers were stable in 0.9% saline, plasma of Swiss mice and in excess of cysteine. The in vivo biodistribution studies using Swiss mice with intramuscular infection in the right thigh showed that

  3. A 220-kilodalton glycoprotein in yeast extract inhibits Staphylococcus aureus adherence to human endothelial cells.

    OpenAIRE

    Elliott, D.A.; Hatcher, V B; Lowy, F D

    1991-01-01

    A 220-kDa glycoprotein from yeast extract causes a twofold decrease in S. aureus adherence to human endothelial cells in vitro. Medium constituents can have a significant effect on bacterial adherence interactions.

  4. Transmission of methicillin-resistant Staphylococcus aureus from food production animals to humans: a review

    NARCIS (Netherlands)

    Broens, E.M.; Cleef, van B.A.G.L.; Graat, E.A.M.; Kluytmans, J.A.J.W.

    2008-01-01

    International surveillance of antimicrobial use in food animal production shows that methicillinresistant Staphylococcus aureus (MRSA), traditionally a human pathogen associated with hospitals, has emerged in the community and animals. Since 1961, MRSA has been causing human infections in hospitals

  5. Staphylococcus aureus biofilms: recent developments in biofilm dispersal.

    Science.gov (United States)

    Lister, Jessica L; Horswill, Alexander R

    2014-01-01

    Staphylococcus aureus is a major cause of nosocomial and community-acquired infections and represents a significant burden on the healthcare system. S. aureus attachment to medical implants and host tissue, and the establishment of a mature biofilm, play an important role in the persistence of chronic infections. The formation of a biofilm, and encasement of cells in a polymer-based matrix, decreases the susceptibility to antimicrobials and immune defenses, making these infections difficult to eradicate. During infection, dispersal of cells from the biofilm can result in spread to secondary sites and worsening of the infection. In this review, we discuss the current understanding of the pathways behind biofilm dispersal in S. aureus, with a focus on enzymatic and newly described broad-spectrum dispersal mechanisms. Additionally, we explore potential applications of dispersal in the treatment of biofilm-mediated infections.

  6. Prevalence of Staphylococcus aureus in Shrimps in Tehran during 2013

    Directory of Open Access Journals (Sweden)

    Mohammad Mehdi Soltan Dallal

    2015-12-01

    Full Text Available Background During fishing and transport, preservation and quality of fish products are importantas well as storage to prevent the growth of pathogenic and toxin producing bacteria.Staphylococcus aureus is one of the most common causes of sea food-borne diseases worldwidedue to contamination of food by preformed enterotoxins. The aim of this study was to compare theprevalence and contamination of S. aureus in marine and farmed shrimps in Tehran fishery center.Methods: A total of 300 samples, including 150 marine, 150 farmed shrimps were selected duringSeptember 2013 to December 2013. Isolation and identification of S. aureus from isolated sampleswere carried out according to conventional methods, and antibiotic susceptibility test wasperformed by modified Kirby-Bauer disc diffusion methodResults: The results of this study showed that 30% of marine and 20% off armed shrimps werecontaminated with S. aureus. The highest resistance was observed with penicillin and ampicillin,whereas 100% were sensitive to vancomycin, clindamycin, ciprofloxacin, and rifampin.Conclusions: Due to relatively high contamination of shrimp by S. aureus more attention shouldbe given during processing and manufacturing.

  7. High throughput multiple locus variable number of tandem repeat analysis (MLVA) of Staphylococcus aureus from human, animal and food sources

    OpenAIRE

    Daniel Sobral; Stefan Schwarz; Dominique Bergonier; Anne Brisabois; Andrea T Feßler; Gilbert, Florence B.; Kristina Kadlec; Benoit Lebeau; Fabienne Loisy-Hamon; Michaël Treilles; Christine Pourcel; Gilles Vergnaud

    2012-01-01

    Staphylococcus aureus is a major human pathogen, a relevant pathogen in veterinary medicine, and a major cause of food poisoning. Epidemiological investigation tools are needed to establish surveillance of S. aureus strains in humans, animals and food. In this study, we investigated 145 S. aureus isolates recovered from various animal species, disease conditions, food products and food poisoning events. Multiple Locus Variable Number of Tandem Repeat (VNTR) analysis (MLVA), known to be highly...

  8. In-vitro and In-vivo Evaluation of Silymarin Nanoliposomes against Isolated Methicillin-resistant Staphylococcus aureus

    OpenAIRE

    Faezizadeh, Zohreh; Gharib, Amir; Godarzee, Masoud

    2015-01-01

    Staphylococcus aureus is an opportunistic pathogen and remains a common cause of burn wound infections. Different studies have shown that entrapment of plant-derived compounds into liposomes could increase their anti-Staphylococcus aureus activity. Silymarin is the bioactive extract from the known plant Silybum marianum L. The objective of this study was to evaluate efficacy of silymarin in free and nanoliposomal forms against isolated methicillin-resistant Staphylococcus aureus (MRSA) strain...

  9. Effect of Staphylococcus aureus and Streptococcus uberis on apoptosis of bovine mammary gland lymphocytes.

    Science.gov (United States)

    Slama, Petr; Sladek, Zbysek; Rysanek, Dusan; Langrova, Tereza

    2009-10-01

    The aim of this study was to determine whether lymphocyte apoptosis is modulated by infections caused by Staphylococcus aureus and Streptococcus uberis. Samples of cell populations were obtained by lavage of the mammary glands at 4 intervals (24, 48, 72 and 168 h) following infection. The percentage of apoptotic lymphocytes peaked at 168 h after challenge with S. aureus or S. uberis. Subsequent experiments focused on in vitro cultivation of mammary gland lymphocytes with S. aureus and S. uberis. These experiments showed a lower percentage of apoptotic lymphocytes following 3h of cultivating cells with bacteria than after cultivation without bacteria. The results demonstrate that during both experimental infection of bovine mammary glands with S. aureus or S. uberis and during in vitro cultivation of lymphocytes with S. aureus or S. uberis, apoptosis of lymphocytes is delayed.

  10. MF59- and Al(OH3-adjuvanted Staphylococcus aureus (4C-Staph vaccines induce sustained protective humoral and cellular immune responses, with a critical role for effector CD4 T cells at low antibody titers.

    Directory of Open Access Journals (Sweden)

    Elisabetta eMonaci

    2015-09-01

    Full Text Available Staphylococcus aureus (S. aureus is an important opportunistic pathogen that may cause invasive life-threatening infections like sepsis and pneumonia. Due to increasing antibiotic-resistance, the development of an effective vaccine against S. aureus is needed. Although a correlate of protection against staphylococcal diseases is not yet established, several findings suggest that both antibodies and CD4 T cells might contribute to optimal immunity. In this study, we show that adjuvanting a multivalent vaccine (4C-Staph with MF59, an oil-in-water emulsion licensed in human vaccines, further potentiated antigen-specific IgG titers and CD4 T cell responses compared to alum and conferred protection in the peritonitis model of S. aureus infection. Moreover, we showed that MF59- and alum-adjuvanted 4C-Staph vaccines induced persistent antigen-specific humoral and T cell responses, and protected mice from infection up to 4 months after immunization. Furthermore, 4C-Staph formulated with MF59 was used to investigate which immune compartment is involved in vaccine-induced protection. Using CD4 T cell-depleted mice or B cell deficient mice, we demonstrated that both T and B cell responses contributed to 4C-Staph vaccine-mediated protective immunity. However, the role of CD4 T cells seemed more evident in the presence of low antibody responses. This study provides preclinical data further supporting the use of the adjuvanted 4C-Staph vaccines against S. aureus diseases, and provides critical insights on the correlates of protective immunity necessary to combat this pathogen.

  11. Mild Staphylococcus aureus skin infection improves the course of subsequent endogenous S. aureus bacteremia in mice

    NARCIS (Netherlands)

    S. van den Berg (Sanne); C.P. de Vogel (Corné); A.F. van Belkum (Alex); I.A.J.M. Bakker-Woudenberg (Irma)

    2015-01-01

    textabstractStaphylococcus aureus carriers with S. aureus bacteremia may have a reduced mortality risk compared to non-carriers. A role for the immune system is suggested. Here, we study in mice the effect of mild S. aureus skin infection prior to endogenous or exogenous S. aureus bacteremia, and ev

  12. Staphylococcus aureus: resistance pattern and risk factors

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    Mohammad Naghavi-Behzad

    2015-03-01

    Full Text Available Introduction: Methicillin resistant Staphylococcus aureus (MRSA has emerged as a nosocomial pathogen of major worldwide importance and is an increasingly frequent cause of community-acquired infections. In this study, different risk factors and MRSA resistance pattern were investigated. Methods: In a 24 months period, all of the patients who were confined to bed in the surgery ward were included in the study. Then they were assessed to find out as if they had MRSA infection when hospitalized and once when they were discharged. Almost 48 h after admission, when patients were discharged, social and medical histories were acquired. Acquired samples were examined. Results: During the present study of 475 patients, 108 patients (22.8% had S. aureus. About frequency of antibiotic resistance among collected S. aureus colonies, erythromycin resistance, was the most frequent antibiotic resistance, also resistance to vancomycin was 0.4% that was the least. Only hospitalization duration had statistically significant correlation with antibiotic resistance, also resistance to erythromycin had statistically significant relation with history of surgery and alcohol consumption. Of all 34 MRSA species, 22 (64.7% samples were resistant to erythromycin, 17 (50.0% resistant to cefoxitin, 5 (14.7% resistant to mupirocin, 1 (2.9% resistant to vancomycin and 1 (2.9% resistant to linezolid. Conclusion: The results of the current study show that among hospitalized patients, there is resistance against methicillin. Since based on results of the study there is resistance against oxacillin and erythromycin in most cases, administering appropriate antibiotics have an important role in minimizing the resistance burden among bacterial species.

  13. Minimally Invasive Dentistry

    Science.gov (United States)

    ... to your desktop! more... What Is Minimally Invasive Dentistry? Article Chapters What Is Minimally Invasive Dentistry? Minimally ... techniques. Reviewed: January 2012 Related Articles: Minimally Invasive Dentistry Minimally Invasive Veneers Dramatically Change Smiles What Patients ...

  14. [Protein toxins of Staphylococcus aureus].

    Science.gov (United States)

    Shamsutdinov, A F; Tiurin, Iu A

    2014-01-01

    Main scientific-research studies regarding protein bacterial toxins of the most widespread bacteria that belong to Staphylococcus spp. genus and in particular the most pathogenic species for humans--Staphylococcus aureus, are analyzed. Structural and biological properties of protein toxins that have received the name of staphylococcus pyrogenic toxins (PTSAg) are presented. Data regarding genetic regulation of secretion and synthesis of these toxins and 3 main regulatory genetic systems (agr--accessory gene regulator, xpr--extracellular protein regulator, sar--staphylococcal accessory regulator) that coordinate synthesis of the most important protein toxins and enzymes for virulence of S. aureus, are presented.

  15. Prevention of Healthcare Associated Staphylococcus aureus Infections

    NARCIS (Netherlands)

    L.G.M. Bode (Lonneke)

    2014-01-01

    markdownabstract__Abstract__ S. aureus colonizes the skin and mucosae of a proportion of the human population. Carriers of S. aureus are at increased risk of developing infections with this pathogen. The aim of this thesis was to add to the prevention of healthcare associated S. aureus infections.

  16. Isolation of invasive Plasmodium yoelii merozoites with a long half-life to evaluate invasion dynamics and potential invasion inhibitors.

    Science.gov (United States)

    Mutungi, Joe Kimanthi; Yahata, Kazuhide; Sakaguchi, Miako; Kaneko, Osamu

    2015-11-01

    Malaria symptoms and pathogenesis are caused by blood stage parasite burdens of Plasmodium spp., for which invasion of red blood cells (RBCs) by merozoites is essential. Successful targeting by either drugs or vaccines directed against the whole merozoite or its antigens during its transient extracellular status would contribute to malaria control by impeding RBC invasion. To understand merozoite invasion biology and mechanisms, it is desired to obtain merozoites that retain their invasion activity in vitro. Accordingly, methods have been developed to isolate invasive Plasmodium knowlesi and Plasmodium falciparum merozoites. Rodent malaria parasite models offer ease in laboratory maintenance and experimental genetic modifications; however, no methods have been reported regarding isolation of high numbers of invasive rodent malaria merozoites. In this study, Plasmodium yoelii-infected RBCs were obtained from infected mice, and mature schizont-infected RBCs enriched via Histodenz™ density gradients. Merozoites retaining invasion activity were then isolated by passing the preparations through a filter membrane. RBC-invaded parasites developed to mature stages in vitro in a synchronous manner. Isolated merozoites were evaluated for retention of invasion activity following storage at different temperatures prior to incubation with uninfected mouse RBCs. Isolated merozoites retained their invasion activity 4h after isolation at 10 or 15 °C, whereas their invasion activity reduced to 0-10% within 30 min when incubated on ice or at 37 °C prior to RBC invasion assay. Images of merozoites at successive steps during RBC invasion were captured by light and transmission electron microscopy. Synthetic peptides derived from the amino acid sequence of the P. yoelii invasion protein RON2 efficiently inhibited RBC invasion. The developed method to isolate and keep invasive P. yoelii merozoites for up to 4h is a powerful tool to study the RBC invasion biology of this parasite

  17. Highly sensitive detection of Staphylococcus aureus directly from patient blood.

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    Padmapriya P Banada

    Full Text Available BACKGROUND: Rapid detection of bloodstream infections (BSIs can be lifesaving. We investigated the sample processing and assay parameters necessary for highly-sensitive detection of bloodstream bacteria, using Staphylococcus aureus as a model pathogen and an automated fluidic sample processing-polymerase chain reaction (PCR platform as a model diagnostic system. METHODOLOGY/PRINCIPAL FINDINGS: We compared a short 128 bp amplicon hemi-nested PCR and a relatively shorter 79 bp amplicon nested PCR targeting the S. aureus nuc and sodA genes, respectively. The sodA nested assay showed an enhanced limit of detection (LOD of 5 genomic copies per reaction or 10 colony forming units (CFU per ml blood over 50 copies per reaction or 50 CFU/ml for the nuc assay. To establish optimal extraction protocols, we investigated the relative abundance of the bacteria in different components of the blood (white blood cells (WBCs, plasma or whole blood, using the above assays. The blood samples were obtained from the patients who were culture positive for S. aureus. Whole blood resulted in maximum PCR positives with sodA assay (90% positive as opposed to cell-associated bacteria (in WBCs (71% samples positive or free bacterial DNA in plasma (62.5% samples positive. Both the assays were further tested for direct detection of S. aureus in patient whole blood samples that were contemporaneous culture positive. S. aureus was detected in 40/45 of culture-positive patients (sensitivity 89%, 95% CI 0.75-0.96 and 0/59 negative controls with the sodA assay (specificity 100%, 95% CI 0.92-1. CONCLUSIONS: We have demonstrated a highly sensitive two-hour assay for detection of sepsis causing bacteria like S. aureus directly in 1 ml of whole blood, without the need for blood culture.

  18. Invasive Salmonellosis in Kilifi, Kenya.

    OpenAIRE

    Muthumbi, E; Morpeth, SC; Ooko, M; Mwanzu, A; Mwarumba, S; Mturi, N.; Etyang, AO; Berkley, JA; Williams, TN; Kariuki, S.; Scott, JA

    2015-01-01

    Background.  Invasive salmonelloses are a major cause of morbidity and mortality in Africa, but the incidence and case fatality of each disease vary markedly by region. We aimed to describe the incidence, clinical characteristics, and antimicrobial susceptibility patterns of invasive salmonelloses among children and adults in Kilifi, Kenya. Methods.  We analyzed integrated clinical and laboratory records for patients presenting to the Kilifi County Hospital between 1998 and 2014. We calculate...

  19. Invasive Salmonellosis in Kilifi, Kenya.

    OpenAIRE

    Muthumbi, E; Morpeth, SC; Ooko, M; Mwanzu, A; Mwarumba, S; Mturi, N.; Etyang, AO; Berkley, JA; Williams, TN; Kariuki, S.; Scott, JA

    2015-01-01

    Invasive salmonelloses are a major cause of morbidity and mortality in Africa, but the incidence and case fatality of each disease vary markedly by region. We aimed to describe the incidence, clinical characteristics, and antimicrobial susceptibility patterns of invasive salmonelloses among children and adults in Kilifi, Kenya.We analyzed integrated clinical and laboratory records for patients presenting to the Kilifi County Hospital between 1998 and 2014. We calculated incidence, and summari...

  20. Methicillin resistant S. aureus in human and bovine mastitis.

    Science.gov (United States)

    Holmes, Mark A; Zadoks, Ruth N

    2011-12-01

    Staphylococcus aureus is a ubiquitous organism that causes a variety of diseases including mastitis in cattle and humans. High-level resistance of S. aureus to β-lactams conferred by a mecA gene encoding a modified penicillin binding protein (PBP2a) was first observed in the early 1960's. These methicillin resistant S. aureus (MRSA) have been responsible for both hospital acquired infections (HA-MRSA) and, more recently, community acquired MRSA (CA-MRSA). A small number of human MRSA mastitis cases and outbreaks in maternity or neonatal units have been reported which are generally the result of CA-MRSA. The establishment of the sequence type 398 (ST398) in farm animals, primarily pigs, in the early 2000's has provided a reservoir of infection for humans and dairy cattle, particularly in continental Europe, described as livestock-associated MRSA (LA-MRSA). Prior to the emergence of ST398 there were sporadic reports of MRSA in bovine milk and cases of mastitis, often caused by strains from human associated lineages. Subsequently, there have been several reports describing bovine udder infections caused by ST-398 MRSA. Recently, another group of LA-MRSA strains was discovered in humans and dairy cattle in Europe. This group carries a divergent mecA gene and includes a number of S. aureus lineages (CC130, ST425, and CC1943) that were hitherto thought to be bovine-specific but are now also found as carriage or clinical isolates in humans. The emergence of MRSA in dairy cattle may be associated with contact with other host species, as in the case of ST398, or with the exchange of genetic material between S. aureus and coagulase negative Staphylococcus species, which are the most common species associated with bovine intramammary infections and commonly carry antimicrobial resistance determinants.

  1. Invasive cranial mycosis our experiences

    Directory of Open Access Journals (Sweden)

    Tapas Kumbhkar

    2013-01-01

    Full Text Available Fungi can cause serious cranial infections in immunocompromised and diabetic patients. Common pathogens mainly include Aspergillus and Mucor. These organisms cause tissue invasion and destruction of adjacent structures (e.g. orbit, ethmoid, sphenoid, maxillary & cavernous sinuses. Mortality and morbidity rate is high despite combined surgical, antifungal and antidiabetic treatment. We present our experience of six cases with such infection.

  2. Risk and prognosis of Staphylococcus aureus bacteremia among individuals with and without end-stage renal disease

    DEFF Research Database (Denmark)

    Nielsen, Lise H; Jensen-Fangel, Søren; Benfield, Thomas;

    2015-01-01

    BACKGROUND: Staphylococcus aureus is a leading cause of bloodstream infections among hemodialysis patients and of exit-site infections among peritoneal dialysis patients. However, the risk and prognosis of Staphylococcus aureus bacteremia among end-stage renal disease patients have not been delin...

  3. Modeling the effect of water activity, pH, and temperature on the probability of enterotoxin production by Staphylococcus aureus

    Science.gov (United States)

    Staphylococcus aureus is a foodborne pathogen widespread in the environment and found in various food products. This pathogen can produce enterotoxins that cause illnesses in humans. The objectives of this study were to develop a probability model of S. aureus enterotoxin production as affected by w...

  4. Plant invasions in China: an emerging hot topic in invasion science

    OpenAIRE

    Jian Liu; Hua Chen; Ingo Kowarik; Yiran Zhang; Renqing Wang

    2012-01-01

    China has shown a rapid economic development in recent decades, and several drivers of this change are known to enhance biological invasions, a major cause of biodiversity loss. Here we review the current state of research on plant invasions in China by analyzing papers referenced in the ISI Web of Knowledge. Since 2001, the number of papers has increased exponentially, indicating that plant invasions in China are an emerging hot topic in invasion science. The analyzed papers cover a broad ra...

  5. 医院耐甲氧西林金黄色葡萄球菌感染的系统评价%Systematic evaluation of hospital-acquired infections caused by methicillin-resistant St ap hy lococcus aureus

    Institute of Scientific and Technical Information of China (English)

    徐小玲; 李爱玲; 贾红

    2015-01-01

    OBJECTIVE To understand the prevalence and distribution of methicillin‐resistant Staphylococcus au‐reus (MRSA) infections through the research of literatures of MRSA infection in China .METHODS From Jan 2005 to Dec 2012 ,the relevant literatures were retrieved from three Chinese databases :WanFang database ,Chinese bi‐omedical literature database (CBM ) ,and China National Knowledge Internet (CNKI) ,and three English databas‐es :Pubmed ,EBSCOP ,and Ovid;totally 34 literatures were included according to strict inclusion and exclusion criteria ,and the statistical analysis was performed .RESULTS The incidence of MRSA infections was 33 .50% (the lowest ) ,92 .61% (the highest ) ,with the median infection rate of 59 .92% .The sputum specimens was the major species source ,and the incidence of respiratory system infections was the highest ,with the median infection rate of 69 .23% ,and the respiratory system infections mainly occurred in the ICU and neurosurgery department where multiple invasive operations were performed ,or the underlying diseases were severe ,or time of use of antibiotics was long .All the MRSA strains were resistant to theβ‐lactams including penicillin G ,cefazolin ,ampicillin ,cefox‐itin ,and amoxicillin , and the strains resistant to vancomycin , teicoplanin , or linezolid have been found . CONCLUSION The isolation rate of the MRSA strains shows an increasingly upward trend ,and the strains are multidrug‐resistant ;the strains resistant to vancomycin have been found .It is necessary to screen according to the common M RSA infection sites ,high‐risk departments ,and high‐risk populations so as to raise the isolation rate of M RSA and the cure rate and reduce the mortality rate .%目的:通过对国内医院耐甲氧西林金黄色葡萄球菌(M RS A )感染文献的研究,了解国内M RS A感染的基本情况及分布。方法在万方、中国生物医学文献数据库(CBM )、中国知网(CNKI)3

  6. Solonamide B Inhibits Quorum Sensing and Reduces Staphylococcus aureus Mediated Killing of Human Neutrophils

    DEFF Research Database (Denmark)

    Nielsen, Anita; Månsson, Maria; Bojer, Martin S.;

    2014-01-01

    that a cyclodepsipeptide termed Solonamide B isolated from the marine bacterium, Photobacterium halotolerans strongly reduces expression of RNAIII, the effector molecule of the agr quorum sensing system. Here we show that Solonamide B interferes with the binding of S. aureus autoinducing peptides (AIPs) to sensor......A controlled virulence gene expression in S. aureus.......Methicillin-resistant Staphylococcus aureus (MRSA) continues to be a serious human pathogen, and particularly the spread of community associated (CA)-MRSA strains such as USA300 is a concern, as these strains can cause severe infections in otherwise healthy adults. Recently, we reported...

  7. Staphylococcus aureus and hand eczema severity

    DEFF Research Database (Denmark)

    Haslund, P; Bangsgaard, N; Jarløv, J O;

    2009-01-01

    BACKGROUND: The role of bacterial infections in hand eczema (HE) remains to be assessed. OBJECTIVES: To determine the prevalence of Staphylococcus aureus in patients with HE compared with controls, and to relate presence of S. aureus, subtypes and toxin production to severity of HE. METHODS......: Bacterial swabs were taken at three different visits from the hand and nose in 50 patients with HE and 50 controls. Staphylococcus aureus was subtyped by spa typing and assigned to clonal complexes (CCs), and isolates were tested for exotoxin-producing S. aureus strains. The Hand Eczema Severity Index...... was used for severity assessment. RESULTS: Staphylococcus aureus was found on the hands in 24 patients with HE and four controls (P aureus was found to be related to increased severity of the eczema (P aureus types on the hands...

  8. Defining invasiveness and invasibility in ecological networks

    OpenAIRE

    C. Hui; Richardson, D. M.; Landi, P; H.O. Minoarivelo; Garnas, J.; Roy, H.E.

    2016-01-01

    The success of a biological invasion is context dependent, and yet two key concepts—the invasiveness of species and the invasibility of recipient ecosystems—are often defined and considered separately. We propose a framework that can elucidate the complex relationship between invasibility and invasiveness. It is based on trait-mediated interactions between species and depicts the response of an ecological network to the intrusion of an alien species, drawing on the concept of community satura...

  9. Contamination during production of heater-cooler units by Mycobacterium chimaera potential cause for invasive cardiovascular infections: results of an outbreak investigation in Germany, April 2015 to February 2016.

    Science.gov (United States)

    Haller, Sebastian; Höller, Christiane; Jacobshagen, Anja; Hamouda, Osamah; Abu Sin, Muna; Monnet, Dominique L; Plachouras, Diamantis; Eckmanns, Tim

    2016-04-28

    Invasive infections with Mycobacterium chimaera were reported in patients with previous open chest surgery and exposure to contaminated heater-cooler units (HCUs). We present results of the surveillance of clinical cases and of contaminated HCUs as well as environmental investigations in Germany up until February 2016. Clinical infections occurred in five male German cases over 50 years of age (range 53-80). Cases had been exposed to HCUs from one single manufacturer during open chest surgery up to five years prior to onset of symptoms. During environmental investigations, M. chimaera was detected in samples from used HCUs from three different countries and samples from new HCUs as well as in the environment at the manufacturing site of one manufacturer in Germany. Our investigation suggests that at least some of the M. chimaera infections may have been caused by contamination of HCUs at manufacturing site. We recommend that until sustainable measures for safe use of HCUs in operation theatres are implemented, users continue to adhere to instructions for use of HCUs and Field Safety Notices issued by the manufacturer, implement local monitoring for bacterial contamination and continuously check the websites of national and European authorities for current recommendations for the safe operation of HCUs.

  10. Contamination during production of heater-cooler units by Mycobacterium chimaera potential cause for invasive cardiovascular infections: results of an outbreak investigation in Germany, April 2015 to February 2016.

    Science.gov (United States)

    Haller, Sebastian; Höller, Christiane; Jacobshagen, Anja; Hamouda, Osamah; Abu Sin, Muna; Monnet, Dominique L; Plachouras, Diamantis; Eckmanns, Tim

    2016-04-28

    Invasive infections with Mycobacterium chimaera were reported in patients with previous open chest surgery and exposure to contaminated heater-cooler units (HCUs). We present results of the surveillance of clinical cases and of contaminated HCUs as well as environmental investigations in Germany up until February 2016. Clinical infections occurred in five male German cases over 50 years of age (range 53-80). Cases had been exposed to HCUs from one single manufacturer during open chest surgery up to five years prior to onset of symptoms. During environmental investigations, M. chimaera was detected in samples from used HCUs from three different countries and samples from new HCUs as well as in the environment at the manufacturing site of one manufacturer in Germany. Our investigation suggests that at least some of the M. chimaera infections may have been caused by contamination of HCUs at manufacturing site. We recommend that until sustainable measures for safe use of HCUs in operation theatres are implemented, users continue to adhere to instructions for use of HCUs and Field Safety Notices issued by the manufacturer, implement local monitoring for bacterial contamination and continuously check the websites of national and European authorities for current recommendations for the safe operation of HCUs. PMID:27168588

  11. AKTIVITAS ANTIBAKTERI GETAH PEPAYA KERING TERHADAP Staphylococcus aureus PADA DANGKE [Antibacterial Activity of Dried Papaya Latex toward Staphylococcus aureus in Dangke

    Directory of Open Access Journals (Sweden)

    Rifah Hestyani Arum

    2014-06-01

    Full Text Available Dangke is a traditional milk curd product, made by coagulation of milk using fresh papaya latex. This product is usually kept at room temperature (27-30ºC until consumption. Dried papaya latex was used in this study to produce dangke, and its effect to S. aureus was determined by direct contact in TSB and dangke. Fresh papaya latex was dried using vacuum oven at 50-55ºC for 22 hours. Dried papaya latex at a concentration of 2.7x10-3 g/100 mL could reduce S. aureus approximately 1 log CFU/mL in TSB after 24 hours. Dried papaya latex and papain could maintain the S. aureus number in dangke within 24 hours storage at room temperature. The antibacterial activity of non-proteolytic compound of papaya latex, i.e ethanolic extract of papaya latex was determined by macrodilution method, resulted an the MIC90 of 8 mg/mL. The cell membrane leakage after exposure was detected by measuring the optical density of bacterial supernatant at 260 nm. The result showed that exposure to increasing antibacterial concentration resulted in increasing of optical density of S. aureus supernatant, indicating that the antibacterial caused the S. aureus membrane leakage. Fluorescence microscopy imaging showed that S. aureus exposure to antibacterial caused membrane leakage thus gave Propidium Iodide (PI chance to penetrate into the cell, as indicated by changing of fluorescence color from green to red.

  12. Sepse por Staphylococus aureus resistente à meticilina adquirida na comunidade no sul do Brasil Sepsis due to community-acquired methicillin-resistant Staphylococcus aureus in southern Brazil

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    Luciane Cristina Gelatti

    2009-08-01

    Full Text Available Staphylococcus aureus resistente à meticilina foi inicialmente descrito como um típico microrganismo adquirido em infecções nosocomiais. No entanto, nos últimos anos Staphylococcus aureus resistente à meticilina adquirido na comunidade é causa de infecções de pele e tecidos moles, mas infecções graves como pneumonia e sepse podem ocorrer. Este relato descreve um caso de sepse em criança, complicado com pneumonia secundária a lesão em partes moles por Staphylococcus aureus resistente à meticilina adquirido na comunidade no Sul do Brasil. O paciente foi atendido em Unidade de Emergência com história de ferimento provocado por trauma em membro inferior que evoluiu para celulite, pneumonia e sepse.Methicillin-resistant Staphylococcus aureus was initially described as a typical microorganism acquired in nosocomial infections. However, over recent years, community-acquired methicillin-resistant Staphylococcus aureus has been a cause of skin and soft-tissue infections. Serious infections such as pneumonia and sepsis can also occur. This report describes a case of sepsis in a child that was complicated by pneumonia secondary to soft tissue lesions that were due to community-acquired methicillin-resistant Staphylococcus aureus in southern Brazil. The patient was attended at the Emergency Unit with a history of injury caused by lower-limb trauma that evolved to cellulitis, pneumonia and sepsis.

  13. Identification of single nucleotide polymorphisms associated with hyperproduction of alpha-toxin in Staphylococcus aureus.

    Directory of Open Access Journals (Sweden)

    Xudong Liang

    Full Text Available The virulence factor α-toxin (hla is needed by Staphylococcus aureus in order to cause infections in both animals and humans. Although the complicated regulation of hla expression has been well studied in human S. aureus isolates, the mechanisms of of hla regulation in bovine S. aureus isolates remain undefined. In this study, we found that many bovine S. aureus isolates, including the RF122 strain, generate dramatic amounts of α-toxin in vitro compared with human clinical S. aureus isolates, including MRSA WCUH29 and MRSA USA300. To elucidate potential regulatory mechanisms, we analyzed the hla promoter regions and identified predominant single nucleotide polymorphisms (SNPs at positions -376, -483, and -484 from the start codon in α-toxin hyper-producing isolates. Using site-directed mutagenesis and hla promoter-gfp-luxABCDE dual reporter approaches, we demonstrated that the SNPs contribute to the differential control of hla expression among bovine and human S. aureus isolates. Using a DNA affinity assay, gel-shift assays and a null mutant, we identified and revealed that an hla positive regulator, SarZ, contributes to the involvement of the SNPs in mediating hla expression. In addition, we found that the bovine S. aureus isolate RF122 exhibits higher transcription levels of hla positive regulators, including agrA, saeR, arlR and sarZ, but a lower expression level of hla repressor rot compared to the human S. aureus isolate WCUH29. Our results indicate α-toxin hyperproduction in bovine S. aureus is a multifactorial process, influenced at both the genomic and transcriptional levels. Moreover, the identification of predominant SNPs in the hla promoter region may provide a novel method for genotyping the S. aureus isolates.

  14. Minimum inhibitory concentration of ciprofloxacin in combination with hexahydroquinoline derivatives against Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    F Amin Harati

    2012-12-01

    Full Text Available Background: Staphylococcus aureus is the most common pathogen responsible for skin and soft tissue infections worldwide. Methicillin-resistant S. aureus is a major cause of both nosocomial and community acquired infections. The emergence of antimicrobial-resistant S. aureus is of global concern. Fluoroquinolone antimicrobials including ciprofloxacin, levofloxacin, and moxifloxacin are used to treat skin and soft tissue infections due to S. aureus. Emergence of ciprofloxacin resistance has increased in community acquired methicillin-resistant S. aureus strains. The aim of this study was to evaluate the minimum inhibitory concentration of ciprofloxacin and hexahydroquino-line derivatives against methicillin- and ciprofloxacin-resistant S. aureus.Methods: Identification of S. aureus was performed by routine microbiological tests in the Department of Pathobiology in Winter 2012. The susceptibility of S. aureus strains to both methicillin and ciprofloxacin was examined by the Kirby-Bauer disk-diffusion method. The minimum inhibitory concentration of ciprofloxacin, hexahydroquinoline derivatives and their combination were separately determined by broth microdilution method against methicillin- and ciprofloxacin-resistant S. aureus.Results: The minimum inhibitory concentration of ciprofloxacin decreased in the presence of hexahydroquinolinein derivatives in comparison with ciprofloxacin alone.Conclusion: This study showed that hexahydroquinoline derivatives enhance the antibacterial effect of ciprofloxacin against methicillin- and ciprofloxacin-resistant S. aureus. Therefore, these derivatives could be used as inhibitors of antibiotic resistance in combination therapies. This enhancement may be related to the inhibitory effect of hexahydroquinoline derivatives on the expression of antibiotic efflux pump in the bacteria. However, the structural features of a fluoroquinolone that determine whether it is affected by efflux transporters are not fully

  15. Characterization of a mouse-adapted Staphylococcus aureus strain.

    Science.gov (United States)

    Holtfreter, Silva; Radcliff, Fiona J; Grumann, Dorothee; Read, Hannah; Johnson, Sarah; Monecke, Stefan; Ritchie, Stephen; Clow, Fiona; Goerke, Christiane; Bröker, Barbara M; Fraser, John D; Wiles, Siouxsie

    2013-01-01

    More effective antibiotics and a protective vaccine are desperately needed to combat the 'superbug' Staphylococcus aureus. While in vivo pathogenicity studies routinely involve infection of mice with human S. aureus isolates, recent genetic studies have demonstrated that S. aureus lineages are largely host-specific. The use of such animal-adapted S. aureus strains may therefore be a promising approach for developing more clinically relevant animal infection models. We have isolated a mouse-adapted S. aureus strain (JSNZ) which caused a severe outbreak of preputial gland abscesses among male C57BL/6J mice. We aimed to extensively characterize this strain on a genomic level and determine its virulence potential in murine colonization and infection models. JSNZ belongs to the MLST type ST88, rare among human isolates, and lacks an hlb-converting phage encoding human-specific immune evasion factors. Naive mice were found to be more susceptible to nasal and gastrointestinal colonization with JSNZ than with the human-derived Newman strain. Furthermore, naïve mice required antibiotic pre-treatment to become colonized with Newman. In contrast, JSNZ was able to colonize mice in the absence of antibiotic treatment suggesting that this strain can compete with the natural flora for space and nutrients. In a renal abscess model, JSNZ caused more severe disease than Newman with greater weight loss and bacterial burden. In contrast to most other clinical isolates, JSNZ can also be readily genetically modified by phage transduction and electroporation. In conclusion, the mouse-adapted strain JSNZ may represent a valuable tool for studying aspects of mucosal colonization and for screening novel vaccines and therapies directed at preventing colonization. PMID:24023720

  16. Characterization of a mouse-adapted Staphylococcus aureus strain.

    Directory of Open Access Journals (Sweden)

    Silva Holtfreter

    Full Text Available More effective antibiotics and a protective vaccine are desperately needed to combat the 'superbug' Staphylococcus aureus. While in vivo pathogenicity studies routinely involve infection of mice with human S. aureus isolates, recent genetic studies have demonstrated that S. aureus lineages are largely host-specific. The use of such animal-adapted S. aureus strains may therefore be a promising approach for developing more clinically relevant animal infection models. We have isolated a mouse-adapted S. aureus strain (JSNZ which caused a severe outbreak of preputial gland abscesses among male C57BL/6J mice. We aimed to extensively characterize this strain on a genomic level and determine its virulence potential in murine colonization and infection models. JSNZ belongs to the MLST type ST88, rare among human isolates, and lacks an hlb-converting phage encoding human-specific immune evasion factors. Naive mice were found to be more susceptible to nasal and gastrointestinal colonization with JSNZ than with the human-derived Newman strain. Furthermore, naïve mice required antibiotic pre-treatment to become colonized with Newman. In contrast, JSNZ was able to colonize mice in the absence of antibiotic treatment suggesting that this strain can compete with the natural flora for space and nutrients. In a renal abscess model, JSNZ caused more severe disease than Newman with greater weight loss and bacterial burden. In contrast to most other clinical isolates, JSNZ can also be readily genetically modified by phage transduction and electroporation. In conclusion, the mouse-adapted strain JSNZ may represent a valuable tool for studying aspects of mucosal colonization and for screening novel vaccines and therapies directed at preventing colonization.

  17. Serosubtipos de meningococo B causantes de enfermedad invasiva en Cantabria y concordancia con la cepa de la vacuna cubana Meningococcus B serosubtypes causing invasive disease in Cantabria [Spain] and agreement with the Cuban vaccine strain

    Directory of Open Access Journals (Sweden)

    Álvaro González de Aledo

    2004-02-01

    Full Text Available Objetivo: Conocer los serosubtipos de meningococo B causantes de enfermedad invasiva en Cantabria y el porcentaje de concordancia con la cepa de la vacuna cubana VA-Mengoc-BC. Métodos: Revisión retrospectiva de todos los casos de enfermedad invasiva por meningococo B declarados a través del sistema de Enfermedades de Declaración Obligatoria (EDO entre el 1 de enero de 1998 y el 28 de febrero de 2003, los aislamientos bacteriológicos del Hospital Universitario Marqués de Valdecilla y la serosubtipificación hecha en el laboratorio de referencia de Majadahonda. Resultados: De los 117 casos declarados, se identificó el serosubtipo de 79 (67,5%. La coincidencia con la cepa vacunal cubana fue del 67, el 71 y el 76% en los grupos de edad de 0 a 19 años, 18 meses a 19 años, y de 4 a 19 años, respectivamente. Incluyendo las cepas con protección cruzada, estos porcentajes se elevan al 83, el 83 y el 84%, respectivamente, en los mismos grupos de edad. Conclusiones: El porcentaje de coincidencia con la cepa vacunal cubana y con las cepas heterólogas con protección cruzada es alto, por lo que esta vacuna podría ser de utilidad para la situación epidemiológica de Cantabria.Objective: To determine the serosubtypes of meningococcus B causing invasive disease in Cantabria and the percentage of agreement with the Cuban vaccine strain, VA-MENGOC-BC. Methods: We performed a retrospective review of all cases of invasive disease due to meningococcus B declared through the Diseases of Mandatory Reporting System between 1st January 1998 and 28th February 2003. The bacteriological isolates of the «Marqués de Valdecilla» University Hospital, and the serosubtyping performed in the Majadahonda reference laboratory (Madrid, Spain were also analyzed. Results: Of the 117 declared cases, serosubtype was identified in 79 (67.5%. The agreement with the Cuban vaccine strain was 67%, 71% and 76% in the age groups of newborn to 19 years, 18 months to 19 years

  18. EDIN-B Promotes the Translocation of Staphylococcus aureus to the Bloodstream in the Course of Pneumonia

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    Johan Courjon

    2015-10-01

    Full Text Available It is crucial to define risk factors that contribute to host invasion by Staphylococcus aureus. Here, we demonstrate that the chromosomally encoded EDIN-B isoform from S. aureus contributes to the onset of bacteremia during the course of pneumonia. Deletion of edinB in a European lineage community-acquired methicillin resistant S. aureus (CA-MRSA strain (ST80-MRSA-IV dramatically decreased the frequency and magnitude of bacteremia in mice suffering from pneumonia. This deletion had no effect on the bacterial burden in both blood circulation and lung tissues. Re-expression of wild-type EDIN-B, unlike the catalytically inactive mutant EDIN-R185E, restored the invasive characteristics of ST80-MRSA-IV.

  19. Antimicrobial proteins from snake venoms: direct bacterial damage and activation of innate immunity against Staphylococcus aureus skin infection.

    Science.gov (United States)

    Samy, R P; Stiles, B G; Gopalakrishnakone, P; Chow, V T K

    2011-01-01

    The innate immune system is the first line of defense against microbial diseases. Antimicrobial proteins produced by snake venoms have recently attracted significant attention due to their relevance to bacterial infection and potential development into new therapeutic agents. Staphylococcus aureus is one of the major human pathogens causing a variety of infections involving pneumonia, toxic shock syndrome, and skin lesions. With the recent emergence of methicillin (MRSA) and vancomycin (VRSA) resistance, S. aureus infection is a serious clinical problem that will have a grave socio-economic impact in the near future. Although S. aureus susceptibility to innate antimicrobial peptides has been reported recently, the protective effect of snake venom phospholipase A₂ (svPLA₂) proteins on the skin from S. aureus infection has been understudied. This review details the protective function of svPLA₂s derived from venoms against skin infections caused by S. aureus. We have demonstrated in vivo that local application of svPLA₂ provides complete clearance of S. aureus within 2 weeks after treatment compared to fusidic acid ointment (FAO). In vitro experiments also demonstrate that svPLA₂ proteins have inhibitory (bacteriostatic) and killing (bactericidal) effects on S. aureus in a dose-dependant manner. The mechanism of bacterial membrane damage and perturbation was clearly evidenced by electron microscopic studies. In summary, svPLA₂s from Viperidae and Elapidae snakes are novel molecules that can activate important mechanisms of innate immunity in animals to endow them with protection against skin infection caused by S. aureus.

  20. D-Test Method for Detection of Inducible Clindamycin Resistance in Staphylococcus Aureus

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    Neda Pak

    2009-09-01

    Full Text Available Objective:Methicillin resistant staphylococcus aureus (MRSA is a frequent cause of infections in children. The purpose of this study was to determine the frequency of nasal colonization of S. aureus in children and detection of inducible clindamycin resistance (ICR by disk approximation test (D-test. Methods:This was a cross-sectional study conducted in Hamedan from 2007 to 2008. 520 nasal swabs were obtained from children under 12 years of age at the time of admission and 287 swabs at the time of discharge. Antibiogram was performed by method of disk diffusion for oxacillin, erythromycin, clindamycin, cefazolin and vancomycin as well as D-test. Chi-square test was applied for statistical analysis. Findings:Out of 520 patients, 118 (22.3% were colonized with S. aureus as community-acquired (CA-S. aureus. Of 287 patients, 64 (22.3% were colonized with isolates of S. aureus at discharge time. Of these 64 patients, 32 cases were colonized with hospital acquired (HA-S. aureus isolates after admission. Only one CA-MRSA isolate was resistant to clindamycin, 5% of 118 CA-S. aureus isolates and 6.3% of HA-S. aureus isolates had inducible clindamycin resistance (D-test. Also 37.5% of CA-MRSA isolates at the time of admission and 22.2% of HA-MRSA isolates at discharge had positive D-test. Conclusion:We emphasize that D-test should be used routinely and clindamycin should not be used in patients with infections caused by inducible resistant S. aureus.

  1. Combined use of Bacteriophage K and a novel Bacteriophage to reduce Staphylococcus aureus biofilm formation

    DEFF Research Database (Denmark)

    Alves, D.R.; Gaudion, A.; Bean, J.E.;

    2014-01-01

    Biofilms are major causes of impairment of wound healing and patient morbidity. One of the most common and aggressive wound pathogens is Staphylococcus aureus, displaying a large repertoire of virulence factors and commonly reduced susceptibility to antibiotics, such as the spread of methicillin-......-resistant S. aureus (MRSA). Bacteriophages are obligate parasites of bacteria. They multiply intracellularly and lyse their bacterial host, releasing their progeny. We isolated a novel phage, DRA88, which has a ...

  2. Experimental Endocarditis Model of Methicillin Resistant Staphylococcus aureus (MRSA) in Rat

    OpenAIRE

    Hady, Wessam Abdel; Bayer, Arnold S.; Xiong, Yan Q.

    2012-01-01

    Endovascular infections, including endocarditis, are life-threatening infectious syndromes1-3. Staphylococcus aureus is the most common world-wide cause of such syndromes with unacceptably high morbidity and mortality even with appropriate antimicrobial agent treatments4-6. The increase in infections due to methicillin-resistant S. aureus (MRSA), the high rates of vancomycin clinical treatment failures and growing problems of linezolid and daptomycin resistance have all further complicated th...

  3. Community-Associated Methicillin-Resistant Staphylococcus aureus: Epidemiology and Clinical Consequences of an Emerging Epidemic

    OpenAIRE

    David, Michael Z.; Daum, Robert S.

    2010-01-01

    Summary: Staphylococcus aureus is an important cause of skin and soft-tissue infections (SSTIs), endovascular infections, pneumonia, septic arthritis, endocarditis, osteomyelitis, foreign-body infections, and sepsis. Methicillin-resistant S. aureus (MRSA) isolates were once confined largely to hospitals, other health care environments, and patients frequenting these facilities. Since the mid-1990s, however, there has been an explosion in the number of MRSA infections reported in populations l...

  4. Targeting Staphylococcus aureus Toxins: A Potential form of Anti-Virulence Therapy

    OpenAIRE

    Cin Kong; Hui-min Neoh; Sheila Nathan

    2016-01-01

    Staphylococcus aureus is an opportunistic pathogen and the leading cause of a wide range of severe clinical infections. The range of diseases reflects the diversity of virulence factors produced by this pathogen. To establish an infection in the host, S. aureus expresses an inclusive set of virulence factors such as toxins, enzymes, adhesins, and other surface proteins that allow the pathogen to survive under extreme conditions and are essential for the bacteria’s ability to spread through ti...

  5. Nasal Carriage as a Source of agr-Defective Staphylococcus aureus Bacteremia

    OpenAIRE

    Smyth, Davida S.; Kafer, Jared M.; Wasserman, Gregory A.; Velickovic, Lili; Mathema, Barun; Robert S Holzman; Knipe, Tiffany A.; Becker, Karsten; von Eiff, Christof; Peters, Georg; Chen, Liang; Kreiswirth, Barry N.; Novick, Richard P.; Shopsin, Bo

    2012-01-01

    Inactivating mutations in the Staphylococcus aureus virulence regulator agr are associated with worse outcomes in bacteremic patients. However, whether agr dysfunction is primarily a cause or a consequence of early bacteremia is unknown. Analysis of 158 paired S. aureus clones from blood and nasal carriage sites in individual patients revealed that recovery of an agr-defective mutant from blood was usually predicted by the agr functionality of carriage isolates. Many agr-positive blood isolat...

  6. Staphylococcus aureus α toxin potentiates opportunistic bacterial lung infections.

    Science.gov (United States)

    Cohen, Taylor S; Hilliard, Jamese J; Jones-Nelson, Omari; Keller, Ashley E; O'Day, Terrence; Tkaczyk, Christine; DiGiandomenico, Antonio; Hamilton, Melissa; Pelletier, Mark; Wang, Qun; Diep, Binh An; Le, Vien T M; Cheng, Lily; Suzich, JoAnn; Stover, C Kendall; Sellman, Bret R

    2016-03-01

    Broad-spectrum antibiotic use may adversely affect a patient's beneficial microbiome and fuel cross-species spread of drug resistance. Although alternative pathogen-specific approaches are rationally justified, a major concern for this precision medicine strategy is that co-colonizing or co-infecting opportunistic bacteria may still cause serious disease. In a mixed-pathogen lung infection model, we find that the Staphylococcus aureus virulence factor α toxin potentiates Gram-negative bacterial proliferation, systemic spread, and lethality by preventing acidification of bacteria-containing macrophage phagosomes, thereby reducing effective killing of both S. aureus and Gram-negative bacteria. Prophylaxis or early treatment with a single α toxin neutralizing monoclonal antibody prevented proliferation of co-infecting Gram-negative pathogens and lethality while also promoting S. aureus clearance. These studies suggest that some pathogen-specific, antibody-based approaches may also work to reduce infection risk in patients colonized or co-infected with S. aureus and disparate drug-resistant Gram-negative bacterial opportunists.

  7. Strain Discrimination of Staphylococcus aureus Using Superantigen Profiles.

    Science.gov (United States)

    Tsen, Hau-Yang; Li, Sheng-Chih; Chiang, Yu-Cheng; Tsai, Shuo-Wen

    2016-01-01

    Staphylococcus aureus is one of the major bacterial species that may cause clinical infection and food-poisoning cases. Strains of this species may produce a series of superantigens (SAgs). Due to the importance of staphylococcal infections, reliable methods for the discrimination of strains of this species are important. Such data may allow us to trace the infection origins and be used for epidemiological study. For strain discrimination, genotyping methods, such as pulsed-field gel electrophoresis (PFGE), random amplified polymorphic DNA (RAPD), and multi-locus sequence typing (MLST), etc., could be used. Recently, toxin gene profiles, which can be used for the elucidation of the genetic and pathogenic relatedness between strains, also have been used to improve the strain discrimination. For S. aureus, as more SAg genes were discovered, the SAg profiles become more useful for the strain discrimination of S. aureus. In this chapter, a method for the discrimination of S. aureus strains using superantigen profiles will be described in detail.

  8. Staphylococcus aureus with reduced susceptibility to vancomycin in healthcare settings.

    Science.gov (United States)

    Spagnolo, A M; Orlando, P; Panatto, D; Amicizia, D; Perdelli, F; Cristina, M L

    2014-12-01

    Glycopeptide resistance in Staphylococcus aureus is a source of great concern because, especially in hospitals, this class of antibiotics, particularly vancomycin, is one of the main resources for combating infections caused by methicillin-resistant Staphylococcus aureus strains (MRSA). Reduced susceptibility to vancomycin (VISA) was first described in 1996 in Japan; since then, a phenotype with heterogeneous resistance to vancomycin (h-VISA) has emerged. H-VISA isolates are characterised by the presence of a resistant subpopulation, typically at a rate of 1 in 10(5) organisms, which constitutes the intermediate stage betweenfully vancomycin-susceptible S. aureus (VSSA) and VISA isolates. As VISA phenotypes are almost uniformly cross-resistant to teicoplanin, they are also called Glycopeptides-intermediate Staphylococcus aureus strains (GISA) and, in the case of heterogeneous resistance to glycopeptides, h-GISA. The overall prevalence of h-VISA is low, accounting for approximately 1.3% of all MRSA isolates tested. Mortality due to h-GISA infections is very high (about 70%), especially among patients hospitalised in high-risk departments, such as intensive care units (ICU). Given the great clinical relevance of strains that are heteroresistant to glycopeptides and the possible negative impact on treatment choices, it is important to draw up and implement infection control practices, including surveillance, the appropriate use of isolation precautions, staff training, hand hygiene, environmental cleansing and good antibiotic stewardship.

  9. Staphylococcus aureus with reduced susceptibility to vancomycin in healthcare settings.

    Science.gov (United States)

    Spagnolo, A M; Orlando, P; Panatto, D; Amicizia, D; Perdelli, F; Cristina, M L

    2014-12-01

    Glycopeptide resistance in Staphylococcus aureus is a source of great concern because, especially in hospitals, this class of antibiotics, particularly vancomycin, is one of the main resources for combating infections caused by methicillin-resistant Staphylococcus aureus strains (MRSA). Reduced susceptibility to vancomycin (VISA) was first described in 1996 in Japan; since then, a phenotype with heterogeneous resistance to vancomycin (h-VISA) has emerged. H-VISA isolates are characterised by the presence of a resistant subpopulation, typically at a rate of 1 in 10(5) organisms, which constitutes the intermediate stage betweenfully vancomycin-susceptible S. aureus (VSSA) and VISA isolates. As VISA phenotypes are almost uniformly cross-resistant to teicoplanin, they are also called Glycopeptides-intermediate Staphylococcus aureus strains (GISA) and, in the case of heterogeneous resistance to glycopeptides, h-GISA. The overall prevalence of h-VISA is low, accounting for approximately 1.3% of all MRSA isolates tested. Mortality due to h-GISA infections is very high (about 70%), especially among patients hospitalised in high-risk departments, such as intensive care units (ICU). Given the great clinical relevance of strains that are heteroresistant to glycopeptides and the possible negative impact on treatment choices, it is important to draw up and implement infection control practices, including surveillance, the appropriate use of isolation precautions, staff training, hand hygiene, environmental cleansing and good antibiotic stewardship. PMID:26137787

  10. Clinicopathologic study of invasive fungal rhinosinusitis caused by Aspergillus and Mucorales%侵袭性曲霉菌及毛霉菌性鼻-鼻窦炎临床病理学分析

    Institute of Scientific and Technical Information of China (English)

    何春燕; 朴颖实; 田澄; 李丽丽; 刘红刚

    2012-01-01

    rhinosinusitis caused by Aspergillus and Mucorales,and to discuss the pathogenesis of tissue injury induced by these two kinds of fungi.Methods The clinical and pathologic features of 19 patients with invasive fungal rhinosinusitis due to Aspergillus (group A) and 16 patients with invasive fungal rhinosinusitis due to Mucorales (group M) were retrospectively reviewed.HE,PAS and GMS stains were performed on all the paraffin-embedded tissues.The diagnosis was confirmed by histologic examination and microbiological culture results.Results Amongst the group A patients,the clinical course was acute in 4 cases and chronic in 15 cases.Thirteen cases had underlying predisposing conditions,including diabetes (number =4),malignant tumor (number =5),history of trauma (number =1) and radical maxillary sinus surgery (number=3).Follow-up information was available in 13 patients.Seven of them died,4 due to fungal encephalopathy and 3 due to underlying diseases.Amongst the group M patients,the clinical course was acute in 14 cases and chronic in 2 cases.Fourteen cases had underlying predisposing conditions,including diabetes (number =8),malignant tumor (number =5) and history of wisdom tooth extraction (number =1).Follow-up information was available in 14 patients.Four of them died of fungal encephalopathy.There was significant difference in clinical onset between the two groups (P =0.01).There was however no difference in terms of underlying predisposing conditions and disease mortality.Histologically,the microorganisms in group A patients formed fungal masses and attached to the mucosal surface,resulting in necrotic bands (11/19).Epithelioid granulomas were conspicuous but multinucleated giant cells were relatively rare.Deep-seated necrosis,granulomatous inflammation against fungal organisms (3/19) and vasculitis with thrombosis (4/19) were not common.On the other hand,large areas of geographic necrosis involving deep-seated tissue could be seen in group M patients (13/16).Isolated

  11. A case report of Small Colony variant of Staphylococcus aureus isolated from a patient with chronic oesteomyelitis in a tertiary care hospital of eastern India

    Directory of Open Access Journals (Sweden)

    Kalidas Rit

    2014-01-01

    Full Text Available Small colony variants (SCVs of Staphylococcus aureus often cause persistant and relapsing infections. SCVs are characterized by a strong reduction in growth rate, atypical colony morphology and unusual biochemical characteristics. We here report a case of chronic oesteomyelitis caused by SCV of Staphyloccous aureus in a middle aged male patient.

  12. Phage sensitivity and prophage carriage in Staphylococcus aureus isolated from foods in Spain and New Zealand.

    Science.gov (United States)

    Gutiérrez, Diana; Rodríguez-Rubio, Lorena; García, Pilar; Billington, Craig; Premarante, Aruni; Rodríguez, Ana; Martínez, Beatriz

    2016-08-01

    Bacteriophages (phages) are a promising tool for the biocontrol of pathogenic bacteria, including those contaminating food products and causing infectious diseases. However, the success of phage preparations is limited by the host ranges of their constituent phages. The phage resistance/sensitivity profile of eighty seven Staphylococcus aureus strains isolated in Spain and New Zealand from dairy, meat and seafood sources was determined for six phages (Φ11, K, ΦH5, ΦA72, CAPSa1 and CAPSa3). Most of the S. aureus strains were sensitive to phage K (Myoviridae) and CAPSa1 (Siphoviridae) regardless of their origin. There was a higher sensitivity of New Zealand S. aureus strains to phages isolated from both Spain (ΦH5 and ΦA72) and New Zealand (CAPSa1 and CAPSa3). Spanish phages had a higher infectivity on S. aureus strains of Spanish dairy origin, while Spanish strains isolated from other environments were more sensitive to New Zealand phages. Lysogeny was more prevalent in Spanish S. aureus compared to New Zealand strains. A multiplex PCR reaction, which detected ΦH5 and ΦA72 sequences, indicated a high prevalence of these prophages in Spanish S. aureus strains, but were infrequently detected in New Zealand strains. Overall, the correlation between phage resistance and lysogeny in S. aureus strains was found to be weak.

  13. Analysis of the features of 45 identified CRISPR loci in 32 Staphylococcus aureus.

    Science.gov (United States)

    Yang, Siyu; Liu, Jing; Shao, Fuye; Wang, Pengfei; Duan, Guangcai; Yang, Haiyan

    2015-08-28

    Staphylococcus aureus (S. aureus) is a common pathogen that can cause serious infections, even death. Because of the horizontal gene transfer (HGT) of antibiotic resistance genes, the drug resistant condition is becoming increasingly prevalent. Recently, an adaptive immunity system, named clustered regularly interspaced short palindromic repeats (CRISPR), was discovered and demonstrated to confer a defense against foreign invading elements that may carry the antibiotic resistance genes. In this study, we reveal the features of 45 identified CRISPR loci and the CRISPR associated gene (Cas) in 32 S. aureus strains from CRISPR database. Five spacers of S. aureus 08BA02176 and MSHR1132 were homologous with foreign genetic sequences from phages or plasmids, even containing a spacer sequence identical to part of some phages' genomes containing lukPV gene that encodes the PVL toxin. Many S. aureus strains with the same CRISPR type shared the same MLST type. CRISPR loci that had 3 or more similar protein loci mostly belonged to the same CRISPR type. We came to the conclusion that the CRISPR/Cas of strains 08BA02176 and MSHR1132 were inherited from a common ancestor or recombined from Staphylococcus lugdunensis. CRISPR loci can be mobilized and can transfer among different but closely related species, and the same types of MLST strains exhibit a higher affinity to the same types of CRISPR loci. Bacteriophages may be the predominant challenge facing S. aureus. The CRISPR/Cas structure may limit the transmission of bacterial virulence among S. aureus.

  14. High-resolution subtyping of Staphylococcus aureus strains by means of Fourier-transform infrared spectroscopy.

    Science.gov (United States)

    Johler, Sophia; Stephan, Roger; Althaus, Denise; Ehling-Schulz, Monika; Grunert, Tom

    2016-05-01

    Staphylococcus aureus causes a variety of serious illnesses in humans and animals. Subtyping of S. aureus isolates plays a crucial role in epidemiological investigations. Metabolic fingerprinting by Fourier-transform infrared (FTIR) spectroscopy is commonly used to identify microbes at species as well as subspecies level. In this study, we aimed to assess the suitability of FTIR spectroscopy as a tool for S. aureus subtyping. To this end, we compared the subtyping performance of FTIR spectroscopy to other subtyping methods such as pulsed field gel electrophoresis (PFGE) and spa typing in a blinded experimental setup and investigated the ability of FTIR spectroscopy for identifying S. aureus clonal complexes (CC). A total of 70 S. aureus strains from human, animal, and food sources were selected, for which clonal complexes and a unique virulence and resistance gene pattern had been determined by DNA microarray analysis. FTIR spectral analysis resulted in high discriminatory power similar as obtained by spa typing and PFGE. High directional concordance was found between FTIR spectroscopy based subtypes and capsular polysaccharide expression detected by FTIR spectroscopy and the cap specific locus, reflecting strain specific expression of capsular polysaccharides and/or other surface glycopolymers, such as wall teichoic acid, peptidoglycane, and lipoteichoic acid. Supervised chemometrics showed only limited possibilities for differentiation of S. aureus CC by FTIR spectroscopy with the exception of CC45 and CC705. In conclusion, FTIR spectroscopy represents a valuable tool for S. aureus subtyping, which complements current molecular and proteomic strain typing. PMID:27021524

  15. Phage sensitivity and prophage carriage in Staphylococcus aureus isolated from foods in Spain and New Zealand.

    Science.gov (United States)

    Gutiérrez, Diana; Rodríguez-Rubio, Lorena; García, Pilar; Billington, Craig; Premarante, Aruni; Rodríguez, Ana; Martínez, Beatriz

    2016-08-01

    Bacteriophages (phages) are a promising tool for the biocontrol of pathogenic bacteria, including those contaminating food products and causing infectious diseases. However, the success of phage preparations is limited by the host ranges of their constituent phages. The phage resistance/sensitivity profile of eighty seven Staphylococcus aureus strains isolated in Spain and New Zealand from dairy, meat and seafood sources was determined for six phages (Φ11, K, ΦH5, ΦA72, CAPSa1 and CAPSa3). Most of the S. aureus strains were sensitive to phage K (Myoviridae) and CAPSa1 (Siphoviridae) regardless of their origin. There was a higher sensitivity of New Zealand S. aureus strains to phages isolated from both Spain (ΦH5 and ΦA72) and New Zealand (CAPSa1 and CAPSa3). Spanish phages had a higher infectivity on S. aureus strains of Spanish dairy origin, while Spanish strains isolated from other environments were more sensitive to New Zealand phages. Lysogeny was more prevalent in Spanish S. aureus compared to New Zealand strains. A multiplex PCR reaction, which detected ΦH5 and ΦA72 sequences, indicated a high prevalence of these prophages in Spanish S. aureus strains, but were infrequently detected in New Zealand strains. Overall, the correlation between phage resistance and lysogeny in S. aureus strains was found to be weak. PMID:27111797

  16. Genetic diversity of multidrug resistant Staphylococcus aureus isolated from clinical and non clinical samples in Egypt.

    Science.gov (United States)

    Bendary, M M; Solyman, S M; Azab, M M; Mahmoud, N F; Hanora, A M

    2016-01-01

    In recent years, the increasing incidence of diseases caused by Staphylococcus aureus (S. aureus) has been noted in the university hospitals of El-Sharkia and Assuit governorates - Egypt. Therefore, we studied the genetic relatedness of multidrug resistant S. aureus isolates from different sources in the above mentioned governorates. One hundred and fifty six S. aureus isolates were divided into 5 different groups, 1 non clinical isolates from different food products and 4 different clinical isolates of human and animal sources in the 2 different governorates. Epidemiological characteristics of 156 S. aureus isolates were determined by phenotypic methods including quantitative antibiogram typing and biofilm production. Genetic typing of 35 multidrug resistant (MDR) isolates (7 from each group) based on 16S rRNA gene sequence, virulence and antimicrobial resistance gene profiles was done. The genetic relatedness of the highest virulent strain from each group was detected based on different single locus sequence typing and multi-locus sequence typing (MLST). S. aureus strains isolated from different sources and geographical areas showed high diversity. The genetic typing revealed different sequence types and different sequences of coa and spa genes. S. aureus isolates were found highly diverse in Egypt. PMID:27609475

  17. REVIEW ON CURRENT WORLDWIDE STATUS, DISTRIBUTION, ECOLOGY AND DIETARY HABITS OF GOLDEN JACKAL, CANIS AUREUS

    Directory of Open Access Journals (Sweden)

    Tripti Negi

    2014-12-01

    Full Text Available The golden jackal is a medium-sized predator and omnivore, with a range covering the southern parts of the Palearctic, South Asia and northeastern Africa. The entire jackal population is now confined to a few clusters grouped into 7 sub-areas with criteria such as connectivity and isolation. Causes of decline seem to be related to the limited habitat availability due to changes in human agro-pastoral activities, which resulted mainly in reduced day-cover availability and possibly reduced food base. This review summarizes the basic aspects of golden jackal distribution, ecology and dietary habits, analyses the main threats and problems of jackal management. The jackals seem to do well in moderately modified agro-systems with non- invasive human activities. Barriers for jackal expansion and population recovery seems to be the mountains with extensive high forests or unbroken scrub, heavy snowy winters and irregular food supply, large intensively cultivated areas without cover, urbanization and established wolf populations. Agro pastoral changes during the past 25-30 years has resulted in habitat and human use changes, which have largely contributed to the massive jackal population declines. Following a short introduction on phylogeny, classification, and evolutionary ecology of the Canidae, this review provides the latest information on the distribution, biology and conservation status of Canid aureus species, organized by geographical region.

  18. Current concepts on the virulence mechanisms of meticillin-resistant Staphylococcus aureus.

    Science.gov (United States)

    Watkins, Richard R; David, Michael Z; Salata, Robert A

    2012-09-01

    Meticillin-resistant Staphylococcus aureus (MRSA) strains are prevalent bacterial pathogens that cause both health care and community-associated infections. Increasing resistance to commonly prescribed antibiotics has made MRSA a serious threat to public health throughout the world. The USA300 strain of MRSA has been responsible for an epidemic of community-associated infections in the US, mostly involving skin and soft tissue but also more serious invasive syndromes such as pneumonia, severe sepsis and endocarditis. MRSA strains are particularly serious and potentially lethal pathogens that possess virulence mechanisms including toxins, adhesins, enzymes and immunomodulators. One of these is Panton-Valentine leukocidin (PVL), a toxin associated with abscess formation and severe necrotizing pneumonia. Earlier studies suggested that PVL was a major virulence factor in community-associated MRSA infections. However, some recent data have not supported this association while others have, leading to controversy. Therefore, investigators continue to search for additional mechanisms of pathogenesis. In this review, we summarize the current understanding of the biological basis of MRSA virulence and explore future directions for research, including potential vaccines and antivirulence therapies under development that might allow clinicians to more successfully treat and prevent MRSA infections. PMID:22745137

  19. Antibacterial activity of long-chain polyunsaturated fatty acids against Propionibacterium acnes and Staphylococcus aureus.

    Science.gov (United States)

    Desbois, Andrew P; Lawlor, Keelan C

    2013-11-01

    New compounds are needed to treat acne and superficial infections caused by Propionibacterium acnes and Staphylococcus aureus due to the reduced effectiveness of agents used at present. Long-chain polyunsaturated fatty acids (LC-PUFAs) are attracting attention as potential new topical treatments for Gram-positive infections due to their antimicrobial potency and anti-inflammatory properties. This present study aimed to investigate the antimicrobial effects of six LC-PUFAs against P. acnes and S. aureus to evaluate their potential to treat infections caused by these pathogens. Minimum inhibitory concentrations were determined against P. acnes and S. aureus, and the LC-PUFAs were found to inhibit bacterial growth at 32-1024 mg/L. Generally, P. acnes was more susceptible to the growth inhibitory actions of LC-PUFAs, but these compounds were bactericidal only for S. aureus. This is the first report of antibacterial activity attributed to 15-hydroxyeicosapentaenoic acid (15-OHEPA) and 15-hydroxyeicosatrienoic acid (HETrE), while the anti-P. acnes effects of the six LC-PUFAs used herein are novel observations. During exposure to the LC-PUFAs, S. aureus cells were killed within 15-30 min. Checkerboard assays demonstrated that the LC-PUFAs did not antagonise the antimicrobial potency of clinical agents used presently against P. acnes and S. aureus. However, importantly, synergistic interactions against S. aureus were detected for combinations of benzoyl peroxide with 15-OHEPA, dihomo-γ-linolenic acid (DGLA) and HETrE; and neomycin with 15-OHEPA, DGLA, eicosapentaenoic acid, γ-linolenic acid and HETrE. In conclusion, LC-PUFAs warrant further evaluation as possible new agents to treat skin infections caused by P. acnes and S. aureus, especially in synergistic combinations with antimicrobial agents already used clinically. PMID:24232668

  20. Antibacterial Activity of Long-Chain Polyunsaturated Fatty Acids against Propionibacterium acnes and Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Andrew P. Desbois

    2013-11-01

    Full Text Available New compounds are needed to treat acne and superficial infections caused by Propionibacterium acnes and Staphylococcus aureus due to the reduced effectiveness of agents used at present. Long-chain polyunsaturated fatty acids (LC-PUFAs are attracting attention as potential new topical treatments for Gram-positive infections due to their antimicrobial potency and anti-inflammatory properties. This present study aimed to investigate the antimicrobial effects of six LC-PUFAs against P. acnes and S. aureus to evaluate their potential to treat infections caused by these pathogens. Minimum inhibitory concentrations were determined against P. acnes and S. aureus, and the LC-PUFAs were found to inhibit bacterial growth at 32–1024 mg/L. Generally, P. acnes was more susceptible to the growth inhibitory actions of LC-PUFAs, but these compounds were bactericidal only for S. aureus. This is the first report of antibacterial activity attributed to 15-hydroxyeicosapentaenoic acid (15-OHEPA and 15-hydroxyeicosatrienoic acid (HETrE, while the anti-P. acnes effects of the six LC-PUFAs used herein are novel observations. During exposure to the LC-PUFAs, S. aureus cells were killed within 15–30 min. Checkerboard assays demonstrated that the LC-PUFAs did not antagonise the antimicrobial potency of clinical agents used presently against P. acnes and S. aureus. However, importantly, synergistic interactions against S. aureus were detected for combinations of benzoyl peroxide with 15-OHEPA, dihomo-γ-linolenic acid (DGLA and HETrE; and neomycin with 15-OHEPA, DGLA, eicosapentaenoic acid, γ-linolenic acid and HETrE. In conclusion, LC-PUFAs warrant further evaluation as possible new agents to treat skin infections caused by P. acnes and S. aureus, especially in synergistic combinations with antimicrobial agents already used clinically.

  1. Skin-Specific Unsaturated Fatty Acids Boost the Staphylococcus aureus Innate Immune Response

    OpenAIRE

    Nguyen, Minh Thu; Hanzelmann, Dennis; Härtner, Thomas; Peschel, Andreas; Götz, Friedrich

    2015-01-01

    Antimicrobial fatty acids (AFAs) protect the human epidermis against invasion by pathogenic bacteria. In this study, we questioned whether human skin fatty acids (FAs) can be incorporated into the lipid moiety of lipoproteins and whether such incorporation would have an impact on innate immune stimulation in the model organism Staphylococcus aureus USA300 JE2. This organism synthesized only saturated FAs. However, when feeding USA300 with unsaturated FAs present on human skin (C16:1, C18:1, o...

  2. Staphylococcus aureus nuclease is an SaeRS-dependent virulence factor.

    Science.gov (United States)

    Olson, Michael E; Nygaard, Tyler K; Ackermann, Laynez; Watkins, Robert L; Zurek, Oliwia W; Pallister, Kyler B; Griffith, Shannon; Kiedrowski, Megan R; Flack, Caralyn E; Kavanaugh, Jeffrey S; Kreiswirth, Barry N; Horswill, Alexander R; Voyich, Jovanka M

    2013-04-01

    Several prominent bacterial pathogens secrete nuclease (Nuc) enzymes that have an important role in combating the host immune response. Early studies of Staphylococcus aureus Nuc attributed its regulation to the agr quorum-sensing system. However, recent microarray data have indicated that nuc is under the control of the SaeRS two-component system, which is a major regulator of S. aureus virulence determinants. Here we report that the nuc gene is directly controlled by the SaeRS two-component system through reporter fusion, immunoblotting, Nuc activity measurements, promoter mapping, and binding studies, and additionally, we were unable identify a notable regulatory link to the agr system. The observed SaeRS-dependent regulation was conserved across a wide spectrum of representative S. aureus isolates. Moreover, with community-associated methicillin-resistant S. aureus (CA MRSA) in a mouse model of peritonitis, we observed in vivo expression of Nuc activity in an SaeRS-dependent manner and determined that Nuc is a virulence factor that is important for in vivo survival, confirming the enzyme's role as a contributor to invasive disease. Finally, natural polymorphisms were identified in the SaeRS proteins, one of which was linked to Nuc regulation in a CA MRSA USA300 endocarditis isolate. Altogether, our findings demonstrate that Nuc is an important S. aureus virulence factor and part of the SaeRS regulon.

  3. Exotic plant invasions to the mediterranean region of Chile: causes, history and impacts Invasión de plantas exóticas en la región mediterránea de Chile: causas, historia e impactos

    Directory of Open Access Journals (Sweden)

    JAVIER A. FIGUEROA

    2004-09-01

    Full Text Available We review the literature on patterns, causes, processes and impacts of exotic plants, primarily in the mediterranean region of Chile, considering three major non-independent drivers of the invasion process: (a Availability of exotic species propagules, (b attributes of the local communities in which exotic species establish and through which they will eventually spread out, and (c attributes of exotic species that either facilitate or constraint their spread into new sites. Regarding availability of propagules, central Chile matorral presents the communities with the greatest incidence of naturalized herbs, followed by the sclerophyllous forest and the espinal scrubland in the coastal range. In contrast, north-central communities have lower numbers and proportions of naturalized species of herbs in their seed banks. Availability and persistence of naturalized herbs do not differ between aboveground vegetation and seed bank. Regarding attributes of local communities associated with the establishment and the spread of exotics, grazing regime and land use emerge as the most prominent causes that render them more prone to invasion by exotics. Evidence on the effect of the fire regime is contradictory and native species richness does not seem to be an important factor. Regarding attributes of exotic species, results suggest that naturalized annuals germinate within a wide temperature range, are highly resistant to cold and dry conditions, and show some degree of physiological dormancy. Additionally, naturalized annuals are highly tolerant to poor soils, but are generally intolerant to shade. These general attributes have largely determined the invasion process in the mediterranean region of Chile. Historical data indicate that an important number of exotic species were intentionally introduced, and that the spread of exotic is uncontrolled. It has been demonstrated that arrival time of exotics is of great relevance to understand present day spread of

  4. Heme Recognition By a Staphylococcus Aureus IsdE

    Energy Technology Data Exchange (ETDEWEB)

    Grigg, J.C.; Vermeiren, C.L.; Heinrichs, D.E.; Murphy, M.E.P.

    2009-06-03

    Staphylococcus aureus is a Gram-positive bacterial pathogen and a leading cause of hospital acquired infections. Because the free iron concentration in the human body is too low to support growth, S. aureus must acquire iron from host sources. Heme iron is the most prevalent iron reservoir in the human body and a predominant source of iron for S. aureus. The iron-regulated surface determinant (Isd) system removes heme from host heme proteins and transfers it to IsdE, the cognate substrate-binding lipoprotein of an ATP-binding cassette transporter, for import and subsequent degradation. Herein, we report the crystal structure of the soluble portion of the IsdE lipoprotein in complex with heme. The structure reveals a bi-lobed topology formed by an N- and C-terminal domain bridged by a single {alpha}-helix. The structure places IsdE as a member of the helical backbone metal receptor superfamily. A six-coordinate heme molecule is bound in the groove established at the domain interface, and the heme iron is coordinated in a novel fashion for heme transporters by Met{sup 78} and His{sup 229}. Both heme propionate groups are secured by H-bonds to IsdE main chain and side chain groups. Of these residues, His{sup 299} is essential for IsdE-mediated heme uptake by S. aureus when growth on heme as a sole iron source is measured. Multiple sequence alignments of homologues from several other Gram-positive bacteria, including the human pathogens pyogenes, Bacillus anthracis, and Listeria monocytogenes, suggest that these other systems function equivalently to S. aureus IsdE with respect to heme binding and transport.

  5. Research on virulence genes and associated mobile genetic elements in Staphylococcus aureus causing pediatric infections%儿童金黄色葡萄球菌感染分离株致病基因和相关可移动遗传元件研究

    Institute of Scientific and Technical Information of China (English)

    李向梅; 尚云晓; 赵长安; 杨永弘; 沈叙庄; 吴德静; 耿文静; 刘颖超; 王传清; 邓秋莲; 郑跃杰; 刘岚; 李昌崇

    2011-01-01

    Objective To study the presence of virulence genes and associated mobile genetic elements in Staphylococ-cus aureus causing pediatric infections. Methods A total of 109 Staphylococcus aureus strains collected between June 2005 and July 2009 were detected for the presence of 19 superantigen genes, 2 exfoliative toxin genes and 3 adhesingenes by polymerase chain reaction. The distribution of virulence genes was analyzed between strains collected from different infections. Results 60 Staphylococcus aureus strains were isolated from children with pneumonia, 49 from children with skin and soft tissue infections. Of the strains, 90.8% harbored superantigen genes, with sek and seq as the most frequent genes (57.8%) .followed by seb (45.9% ) and sea (40.4% ). The sed and etd genes were not found in any of the strains tested. Thirty-seven superantigen genotypes were observed, of which the genotypes seb-sek-seq ( 20.2% ) were the majority. About 78.4% (29/37) of the superantigen genotypes could beconsidered combinations of the superantigenic toxin gene-encoding profiles of mobile genetic elements, sek-seq without seb was found in 12 strains, Seb-seq without sek and seb-sek without seq was respectively found in 1 strain. 10 of the tst-1 -positive strains harbored seb. 4 of the sej-positive strains harbored ser.3 adhesin genes bbp、sdrE and can were present in 91.7% 、 77.1%, 30.3% of the strains, respectively. Seb,seq,bbp,sdrE were significantly associated with skin and soft tissue infections (P < 0.05). Seg, sei, sen, seo and can were significantly associated with pneumonia (P < 0.05). Conclusion The distribution of superantigen genes in Staphylococcus aureus isolated from children with pneumonia and skin and soft tissue infections implies the existence of new types or variants of mobile genetic elements in these strains. The frequencies of carriage of the 3 adhesin genes differ from other geographic areas. The roles of virulence genes in these two kinds of infections need

  6. Postoperative Staphylococcus aureus infections in Medicare beneficiaries.

    Directory of Open Access Journals (Sweden)

    Moaven Razavi

    Full Text Available Staphylococcus aureus (S. aureus infections are important because of their increasing frequency, resistance to antibiotics, and high associated rates of disabilities and deaths. We examined the incidence and correlates of S. aureus infections following 219,958 major surgical procedures in a 5% random sample of fee-for-service Medicare beneficiaries from 2004-2007. Of these surgical patients, 0.3% had S. aureus infections during the hospitalizations when index surgical procedures were performed; and 1.7% and 2.3%, respectively, were hospitalized with infections within 60 days or 180 days following admissions for index surgeries. S. aureus infections occurred within 180 days in 1.9% of patients following coronary artery bypass graft surgery, 2.3% following hip surgery, and 5.9% following gastric or esophageal surgery. Of patients first hospitalized with any major infection reported during the first 180 days after index surgery, 15% of infections were due to S. aureus, 18% to other documented organisms, and no specific organism was reported on claim forms in 67%. Patient-level predictors of S. aureus infections included transfer from skilled nursing facilities or chronic hospitals and comorbid conditions (e.g., diabetes, congestive heart failure, chronic obstructive pulmonary disease, and chronic renal disease. In a logarithmic regression, elective index admissions with S. aureus infection stayed 130% longer than comparable patients without that infection. Within 180 days of the index surgery, 23.9% of patients with S. aureus infection and 10.6% of patients without this infection had died. In a multivariate logistic regression of death within 180 days of admission for the index surgery with adjustment for demographics, co-morbidities, and other risks, S. aureus was associated with a 42% excess risk of death. Due to incomplete documentation of organisms in Medicare claims, these statistics may underestimate the magnitude of S. aureus infection

  7. 沿着水平井钻井液侵入对储层污染评价%Evaluation on Pollution of the Reservoir Caused by Drilling Fluid Invasion Along the Horizontal Well

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Drilling fluid invasion will cause different degrees of pollution to the reservoir. On the one hand, it makes the reservoir pore jam;on the other hand, the relative permeability decreases due to the fluid saturation change after drilling fluid invasion, which all will lead to oil production reducing. Therefore, it’s very necessary to carry out the pollution evaluation around the horizontal well area. In this paper, drilling fluid invasion depth of two-phase flow along the horizontal well was calculated by using finite element numerical simulation method. Combined with water saturation in polluted area and relative permeability curve, average permeability and skin factor of the polluted area were calculated. The relationship between wellbore reservoir pollution level and different mud viscosity, positive pressure during drilling fluid invasion was studied by the method of single factor analysis. The research on relationship between mud viscosity and pollution degree shows that, in four mud viscosity schemes, with the increase of mud viscosity, the pollution degree decreases. The skin factor of No.1 scheme is higher than that of No.2 scheme by 50.7%, the skin factor of No.2 scheme is higher than that of No.3 scheme by 48.2%, and the skin factor of No.3 scheme is higher than that of No.4 scheme by 36.5%. The research on relationship between positive pressure and pollution degree shows that, with the increase of positive pressure difference, the pollution degree increases. The skin factors of 1 MPa pressure difference and 3 MPa pressure difference are 0.039 and 2.003, the skin factor of 3 MPa pressure difference is significantly higher than that of 1 MPa pressure difference.%钻井液侵入会对油层造成不同程度的污染,一方面使油层孔隙堵塞,另一方面钻井液侵入后由于流体的饱和度发生变化后导致相对渗透率下降,都将导致油井产量降低。因此,必须对水平井井筒周围的污染区进行污染评价。

  8. Antimicrobial activity of some sulfonamide derivatives on clinical isolates of Staphylococus aureus

    Directory of Open Access Journals (Sweden)

    Bekdemir Yunus

    2008-08-01

    Full Text Available Abstract Background Staphylococcus aureus is a non-motile, gram positive, non-sporforming, facultative anaerobic microorganism. It is one of the important bacteria as a potential pathogen specifically for nosocomial infections. The sulfonamide derivative medicines are preferred to cure infection caused by S. aureus due to methicillin resistance. Methods Antimicrobial activity of four sulfonamide derivatives have been investigated against 50 clinical isolates of S. aureus and tested by using MIC and disc diffusion methods. 50 clinical isolate which collected from specimens of patients who are given medical treatment in Ondokuz Mayis University Medical School Hospital. A control strain of S. aureus ATCC 29213 was also tested. Results The strongest inhibition was observed in the cases of I [N-(2-hydroxy-4-nitro-phenyl-4-methyl-benzensulfonamid], and II [N-(2-hydroxy-5-nitro-phenyl-4-methyl-benzensulfonamid] against S. aureus. Compound I [N-(2-hydroxy-4-nitro-phenyl-4-methyl-benzensulfonamid] showed higher effect on 21 S. aureus MRSAisolates than oxacillin antibiotic. Introducing an electron withdrawing on the ring increased the antimicrobial activity remarkably. Conclusion This study may help to suggest an alternative possible leading compound for development of new antimicrobial agents against MRSA and MSSA resistant S. aureus. It was also shown here that that clinical isolates of 50 S. aureus have various resistance patterns against to four sulfonamide derivatives. It may also be emphasized here that in vitro antimicrobial susceptibility testing results for S. aureus need standardization with further studies and it should also have a correlation with in vivo therapeutic response experiments.

  9. Immunological role of nasal staphylococcus aureus carriage in patients with persistent allergic rhinitis

    Directory of Open Access Journals (Sweden)

    Mohamed Yousif Atia

    2008-10-01

    Full Text Available Nasal carriage of staphylococcus aureus (S.aureus exerts immunomodulatory effect in patients with atopic dermatitis and it may contribute to airway inflammation and allergic response in patients with allergic rhinitis. We Aim to investigate the frequency of nasal S.aureus carriage in patients with persistent allergic rhinitis and its possible influence on their symptoms and immune markers. We chosed 20 non smoker patients with house dust mite (HDM allergy causing allergic rhinitis and 20 non smoker healthy subjects matched for age and sex. For all subjects rhinoscopy was done, skin prick test, nasal culture for S.aureus, nasal interleukin 4,nasal total IgE, serum total IgE and serum specific IgE(SSIgE for HDM. Nasal S.aureus was detected in 16/20 patients (80% and 5/20 (25% in healthy subjects with highly significant statistical difference plt0.01. Correlation of nasal staph.aureus count and different systemic and local immune markers revealed highly significant positive correlation between nasal S.aureus count and serum total IgE (r = 0.78, plt0.01 and significant positive correlation with SSIgE (HDM (r = 0.53, plt0.05, nasal total IgE (r = 0.39, plt0.05 and nasal IL-4 (r = 0.55, plt0.05. Nasal staph.aureus actively modulated the immune reaction in persistent allergic rhinitis patients by promoting local IgE production, so we recommend early detection and treatment of S.aureus carriage in patients

  10. Esophagectomy - minimally invasive

    Science.gov (United States)

    Minimally invasive esophagectomy; Robotic esophagectomy; Removal of the esophagus - minimally invasive; Achalasia - esophagectomy; Barrett esophagus - esophagectomy; Esophageal cancer - esophagectomy - laparoscopic; Cancer of the ...

  11. Mastite com lesões sistêmicas por Staphylococus aureus subesp. aureus em coelhos Mastitis with systemic lesions due to Staphylococus aureus subesp. aureus in rabbits

    OpenAIRE

    Sandra Davi Traverso; Leonardo da Cunha; Joaquim César Teixeira Fernandes; Alexandre Paulino Loretti; Adriana Rhoden; Elsio Wunder Jr.; David Driemeier

    2003-01-01

    Em uma criação composta por 1800 coelhos, 33% das matrizes apresentaram mastite e lesões cutâneas crostosas e purulentas. Estes animais apresentavam-se entre 10 a- 12 meses de idade e em segunda parição. Quinze coelhos afetados foram sacrificados e necropsiados. Na necropsia, além das lesões cutâneas haviam microabscessos em diversos órgãos. Das amostras coletadas isolou-se Staphylococcus aureus subesp. aureus. S. aureus subesp. aureus também foi isolado de "swab" nasal coletado do tratador e...

  12. Methicillin-Resistant Staphylococcus aureus (MRSA) Treatment

    Science.gov (United States)

    ... Laboratory of Bacteriology Network on Antimicrobial Resistance in Staphylococcus aureus (NARSA) Antibacterial Resistance Leadership Group (ARLG) NIAID Antimicrobial Resistance Funding Information ...

  13. Methicillin-Resistant Staphylococcus aureus (MRSA) Diagnosis

    Science.gov (United States)

    ... Laboratory of Bacteriology Network on Antimicrobial Resistance in Staphylococcus aureus (NARSA) Antibacterial Resistance Leadership Group (ARLG) NIAID Antimicrobial Resistance Funding Information ...

  14. Staphylococcus aureus-induced G2/M phase transition delay in host epithelial cells increases bacterial infective efficiency.

    Science.gov (United States)

    Alekseeva, Ludmila; Rault, Lucie; Almeida, Sintia; Legembre, Patrick; Edmond, Valérie; Azevedo, Vasco; Miyoshi, Anderson; Even, Sergine; Taieb, Frédéric; Arlot-Bonnemains, Yannick; Le Loir, Yves; Berkova, Nadia

    2013-01-01

    Staphylococcus aureus is a highly versatile, opportunistic pathogen and the etiological agent of a wide range of infections in humans and warm-blooded animals. The epithelial surface is its principal site of colonization and infection. In this work, we investigated the cytopathic effect of S. aureus strains from human and animal origins and their ability to affect the host cell cycle in human HeLa and bovine MAC-T epithelial cell lines. S. aureus invasion slowed down cell proliferation and induced a cytopathic effect, resulting in the enlargement of host cells. A dramatic decrease in the number of mitotic cells was observed in the infected cultures. Flow cytometry analysis revealed an S. aureus-induced delay in the G2/M phase transition in synchronous HeLa cells. This delay required the presence of live S. aureus since the addition of the heat-killed bacteria did not alter the cell cycle. The results of Western blot experiments showed that the G2/M transition delay was associated with the accumulation of inactive cyclin-dependent kinase Cdk1, a key inducer of mitosis entry, and with the accumulation of unphosphorylated histone H3, which was correlated with a reduction of the mitotic cell number. Analysis of S. aureus proliferation in asynchronous, G1- and G2-phase-enriched HeLa cells showed that the G2 phase was preferential for bacterial infective efficiency, suggesting that the G2 phase delay may be used by S. aureus for propagation within the host. Taken together, our results divulge the potential of S. aureus in the subversion of key cellular processes such as cell cycle progression, and shed light on the biological significance of S. aureus-induced host cell cycle alteration.

  15. Staphylococcus aureus-induced G2/M phase transition delay in host epithelial cells increases bacterial infective efficiency.

    Directory of Open Access Journals (Sweden)

    Ludmila Alekseeva

    Full Text Available Staphylococcus aureus is a highly versatile, opportunistic pathogen and the etiological agent of a wide range of infections in humans and warm-blooded animals. The epithelial surface is its principal site of colonization and infection. In this work, we investigated the cytopathic effect of S. aureus strains from human and animal origins and their ability to affect the host cell cycle in human HeLa and bovine MAC-T epithelial cell lines. S. aureus invasion slowed down cell proliferation and induced a cytopathic effect, resulting in the enlargement of host cells. A dramatic decrease in the number of mitotic cells was observed in the infected cultures. Flow cytometry analysis revealed an S. aureus-induced delay in the G2/M phase transition in synchronous HeLa cells. This delay required the presence of live S. aureus since the addition of the heat-killed bacteria did not alter the cell cycle. The results of Western blot experiments showed that the G2/M transition delay was associated with the accumulation of inactive cyclin-dependent kinase Cdk1, a key inducer of mitosis entry, and with the accumulation of unphosphorylated histone H3, which was correlated with a reduction of the mitotic cell number. Analysis of S. aureus proliferation in asynchronous, G1- and G2-phase-enriched HeLa cells showed that the G2 phase was preferential for bacterial infective efficiency, suggesting that the G2 phase delay may be used by S. aureus for propagation within the host. Taken together, our results divulge the potential of S. aureus in the subversion of key cellular processes such as cell cycle progression, and shed light on the biological significance of S. aureus-induced host cell cycle alteration.

  16. Proteomic Characterization of Lytic Bacteriophages of Staphylococcus aureus Isolated from Sewage Affluent of India

    Science.gov (United States)

    Sangha, Kamalpreet Kaur; Kumar, B. V. Sunil; Agrawal, Ravi Kant; Verma, Ramneek

    2014-01-01

    Staphylococcus aureus is a Gram-positive bacterium that causes a variety of diseases, including bovine mastitis, which has severe economic consequences. Standard antibiotic treatment results in selection of resistant strains, leading to need for an alternative treatment such as bacteriophage therapy. Present study describes isolation and characterization of a staphylococcal phage from sewage samples. S. aureus isolates obtained from microbial type culture collection (MTCC), Chandigarh, India, were used to screen staphylococcal phages. A phage designated as ΦMSP was isolated from sewage samples by soft agar overlay method. It produced clear plaques on tryptone soya agar overlaid with S. aureus. Transmission electron microscopy revealed that the phage had an icosahedral symmetry. It had 5 major proteins and possessed a peptidoglycan hydrolase corresponding to 70 kDa. ΦMSP infection induced 26 proteins to be uniquely expressed in S. aureus. This phage can be proposed as a candidate phage to treat staphylococcal infections. PMID:27355013

  17. Isolation and Identification of Vancomycin Resistant Staphylococcus aureus from Post Operative Pus Sample

    Directory of Open Access Journals (Sweden)

    Subhankari Prasad Chakraborty1, Santanu KarMahapatra1, Manjusri Bal2 and Somenath Roy1*

    2011-04-01

    Full Text Available Staphylococcus aureus is most frequently isolated pathogen causing bloodstream infections, skin and soft tissue infections and pneumonia. Recently, S. aureus have evolved resistance to both synthetic and traditional antibiotics. This study was carried out to isolate pathogenic S. aureus from post-operative pus sample, and VRSA was identified by evaluation of resistance patterns using conventional antibiotics. Thirty post operative pus samples were collected from nearby Hospital and species identification was confirmed by Gram staining, standard biochemical tests and PCR amplification of the nuc gene. Antibiotic susceptibility tests were carried out by MIC, MBC, DAD test and BHI vancomycin screening agar. VRSA were confirmed by PCR amplification of the vanA and vanB genes. From this study, it was observed that isolated S. aureus strains are pathogenic; 30% of strains were resistant to penicillin G, ampicillin and erythromycin; 26.67% strains were resistant to cephotaxime, gentamycin, streptomycin, tetracycline, chloramphenicol, norfloxacin, methicillin and vancomycin.

  18. Staphylococcus aureus and influenza A virus stimulate human bronchoalveolar cells to release histamine and leukotrienes

    DEFF Research Database (Denmark)

    Clementsen, P; Bisgaard, H; Pedersen, M;

    1989-01-01

    Mediator release was examined from superficially lying cells in the airway epithelium obtained by bronchoalveolar lavage (BAL) in 13 non-atopic individuals. The BAL-cells were incubated (20 min, 37 degrees C) with Staphylococcus (Staph.) aureus or with human influenza A virus Staph. aureus...... was found to release histamine from cells from 7 of the 13 individuals and influenza A virus in 3 of 5 persons. Furthermore, Staph, aureus stimulated the BAL-cells to release leukotriene B4 in 7 of 11 subjects, whereas no release was found by influenza A virus in 7 examined persons. When cells from 4...... persons were stimulated with Staph. aureus no release of leukotriene C4 was found. The mediator release caused by bacteria and virus might be of importance for the exacerbation of bronchial asthma in upper respiratory tract infections, since histamine is assumed to increase the epithelial permeability...

  19. Buah Mengkudu (Morinda citrifolia Meningkatkan Respon Imun Mencit (Mus musculus Terhadap Infeksi Bakteri Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Mufidah Zumrotul

    2015-11-01

    Full Text Available Noni (Morinda citrifolia Increase Immune Response in Mice (Mus musculus Infected Staphylococcus aureus. Infection disease caused by bacteria is one of the illness in several developing countries including in Indonesia, with high mortality rate. Infection of  S. aureus as the cause of problem resistance for antibiotic or multi drug resistance are giving the therapy of drug itself with change to medical herbal. The aim of this study is known the role of M.citrifolia extract to increase immune response of mice with infectioned of S. aureus. Mice were divided into two groups there are Non Infection and infection. Non Infection is without S. aureus and than infection has S. aureus. The each groups are including control, dose 1 (25 mg/kg BW, dose 2 (100 mg/kg BW, and dose 3 (300 mg/kg BW. Relative number of lymphocyte T cell (CD4+ subsets was measured  using the BD FACSCaliburTM Flowcytometer. Data were analyzed using Analysis of Varians (p<0,05 and using SPSS 16 for windows. The result showed that administration of  M. citrifolia crude extract in non infection groups was significantly increase the relative amounts T cell subsets (CD4+. Noni fruit extract can used as prevention therapy on infection disease of S. aureus bacteria because it contains active compounds that are anti-inflammation

  20. Acute haematogenous community-acquired methicillin-resistant Staphylococcus aureus osteomyelitis in an adult: Case report and review of literature

    Directory of Open Access Journals (Sweden)

    Dhanoa Amreeta

    2012-10-01

    Full Text Available Abstract Background Methicillin-resistant Staphylococcus aureus (MRSA has of late emerged as a cause of community-acquired infections among immunocompetent adults without risk factors. Skin and soft tissue infections represent the majority of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA clinical presentations, whilst invasive and life-threatening illness like necrotizing pneumonia, necrotizing fasciitis, pyomyositis, osteomyelitis and sepsis syndrome are less common. Although more widely described in the pediatric age group, the occurrence of CA-MRSA osteomyelitis in adults is an uncommonly reported entity. Case presentation We describe an invasive CA-MRSA infection in a 28 year-old previously healthy male, manifesting with bacteraemia, osteomyelitis of femur, pyomyositis and septic arthritis of the knee. Initially a preliminary diagnosis of osteosarcoma was suggested by imaging studies and patient underwent a bone biopsy. MRSA was subsequently isolated from blood cultures taken on day of admission, bone, tissue and pus cultures. Incision and drainage of abscess was performed and patient was treated with vancomycin, with fusidic acid added later. It took 6 months for the inflammatory markers to normalize, warranting 6-months of anti-MRSA therapy. Patient was a fervent deer hunter and we speculate that he acquired this infection from extensive direct contact with deer. Molecular characterization of this isolate showed that it belonged to multilocus sequence type (MLST ST30 and exhibited the staphylococcal chromosome cassette mec (SCCmec type IV, staphylococcus protein A (spa type t019, accessory gene regulator (agr type III and dru type dt10m. This strain harbored Panton-Valentine leukocidin (pvl genes together with 3 other virulent genes; sei (enterotoxin, hlg (hemolysin and fnbA (fibronectin binding protein. Conclusion This case study alerts physicians that beyond the most commonly encountered skin and soft tissue

  1. Characterisation of Staphylococcus aureus bacteraemia at Tygerberg hospital

    NARCIS (Netherlands)

    Orth, H.; Dreyer, Z.S.; Makgotlho, E.; Oosthuysen, W.; Sinha, B.; Wasserman, E.

    2013-01-01

    To elucidate the local epidemiology of Staphylococcus aureus bacteraemia, we characterised blood culture isolates using molecular methods and prospectively collected clinical data to determine the occurrence of community-acquired, methicillinresistant S. aureus (MRSA). Consecutive S. aureus blood cu

  2. Shedding of Staphylococcus aureus and methicillin-resistant Staphylococcus aureus from adult and pediatric bathers in marine waters

    Directory of Open Access Journals (Sweden)

    Sinigalliano Christopher D

    2011-01-01

    Full Text Available Abstract Background Staphylococcus aureus including methicillin resistant S. aureus, MRSA, are human colonizing bacteria that commonly cause opportunistic infections primarily involving the skin in otherwise healthy individuals. These infections have been linked to close contact and sharing of common facilities such as locker rooms, schools and prisons Waterborne exposure and transmission routes have not been traditionally associated with S. aureus infections. Coastal marine waters and beaches used for recreation are potential locations for the combination of high numbers of people with close contact and therefore could contribute to the exposure to and infection by these organisms. The primary aim of this study was to evaluate the amount and characteristics of the shedding of methicillin sensitive S. aureus, MSSA and MRSA by human bathers in marine waters. Results Nasal cultures were collected from bathers, and water samples were collected from two sets of pools designed to isolate and quantify MSSA and MRSA shed by adults and toddlers during exposure to marine water. A combination of selective growth media and biochemical and polymerase chain reaction analysis was used to identify and perform limited characterization of the S. aureus isolated from the water and the participants. Twelve of 15 MRSA isolates collected from the water had identical genetic characteristics as the organisms isolated from the participants exposed to that water while the remaining 3 MRSA were without matching nasal isolates from participants. The amount of S. aureus shed per person corresponded to 105 to 106 CFU per person per 15-minute bathing period, with 15 to 20% of this quantity testing positive for MRSA. Conclusions This is the first report of a comparison of human colonizing organisms with bacteria from human exposed marine water attempting to confirm that participants shed their own colonizing MSSA and MRSA into their bathing milieu. These findings clearly

  3. 2-D GEL ELECTROPHORESIS MAP OF METHICILLIN-RESISTANT STAPHYLOCOCCUS AUREUS TREATED WITH QUERCUS INFECTORIA GALL EXTRACT

    OpenAIRE

    Dayang Fredalina Basri; Lee Seng Aik; Radhiah Khairon; Mariati Abdul Rahman

    2013-01-01

    The widespread outbreak of Methicillin-Resistant Staphylococcus Aureus (MRSA) has caused clinical and epidemiological concern in hospital environment. The emergence of Vancomycin-Intermediate S. Aureus (VISA) and, more recently, Vancomycin-Resistant S. Aureus (VRSA) has further alarmed clinician and scientist worlwide. The objective of this study is to determine the optimum concentration of sample protein from MRSA after treatment with acetone extract from Quercus infectoria gall. Comparison ...

  4. Small Colony variants of Staphylococcus aureus isolated from a patient with infective endocarditis: a case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Sayan Bhattacharyya

    2012-06-01

    Full Text Available Staphylococcus aureus produces a particular morphological variant called small colony variant(SCV which is responsible for persistent subclinical infections in predisposed individuals and is usually resistant to aminoglycosides and cell wall active antibiotics. Infections by SCV of S. aureus is an upcoming problem due to difficulty in laboratory diagnosis and resistance to antimicrobial chemotherapy. We here report a case of infective endocarditis caused by SCV of Staphylococcus aureus in a pediatric patient.

  5. Staphylococcus aureus and methicillin-resistant S. aureus (MRSA) at ambient freshwater beaches

    Science.gov (United States)

    Fogarty, Lisa R.; Haack, Sheridan K.; Johnson, Heather E.; Brennan, Angela K.; Isaacs, Natasha M.; Spencer, Chelsea

    2015-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) are a threat to human health worldwide, and although detected at marine beaches, they have been largely unstudied at freshwater beaches. Genes indicating S. aureus (SA; femA) and methicillin resistance (mecA) were detected at 11 and 12 of 13 US Great Lakes beaches and in 18% or 27% of 287 recreational water samples, respectively. Eight beaches had mecA + femA (potential MRSA) detections. During an intensive study, higher bather numbers, staphylococci concentrations, and femA detections were found in samples collected after noon than before noon. Local population density, beach cloud cover, and beach wave height were significantly correlated with SA or MRSA detection frequency. The Panton-Valentine leukocidin gene, associated with community-acquired MRSA, was detected in 12 out of 27 potential MRSA samples. The femA gene was detected less frequently at beaches that met US enterococci criteria or EU enterococci ‘excellent’ recreational water quality, but was not related to Escherichia coli-defined criteria. Escherichia coli is often the only indicator used to determine water quality at US beaches, given the economic and healthcare burden that can be associated with infections caused by SA and MRSA, monitoring of recreational waters for non-fecal bacteria such as staphylococci and/or SA may be warranted.

  6. Human-associated Staphylococcus aureus strains within great ape populations in Central Africa (Gabon).

    Science.gov (United States)

    Nagel, M; Dischinger, J; Türck, M; Verrier, D; Oedenkoven, M; Ngoubangoye, B; Le Flohic, G; Drexler, J F; Bierbaum, G; Gonzalez, J-P

    2013-11-01

    The risk of serious infections caused by Staphylococcus aureus is well-known. However, most studies regarding the distribution of (clinically relevant) S. aureus among humans and animals took place in the western hemisphere and only limited data are available from (Central) Africa. In this context, recent studies focused on S. aureus strains in humans and primates, but the question of whether humans and monkeys share related S. aureus strains or may interchange strains remained largely unsolved. In this study we aimed to evaluate the distribution and spread of human-like S. aureus strains among great apes living in captivity. Therefore, a primate facility at the International Centre for Medical Research of Franceville (Gabon) was screened. We detected among the primates a common human S. aureus strain, belonging to the spa-type t148. It was isolated from three different individuals of the western lowland gorilla (Gorilla gorilla gorilla), of which one individual showed a large necrotizing wound. This animal died, most probably of a staphylococcal sepsis. Additionally, we discovered the t148 type among chimpanzees (Pan troglodytes) that were settled in the immediate neighbourhood of the infected gorillas. A detailed analysis by pulsed field gel electrophoresis showed that the gorilla and chimpanzee isolates represented two closely related strains. To our knowledge, this is the first report of a human-associated S. aureus strain causing disease in great apes. The simultaneous detection in gorillas and chimpanzees indicated an interspecies transmission of this S. aureus strain. Our results recommend that protection of wild animals must not only be based on habitat conservation, but also on the assessment of the risk of contact with human pathogens.

  7. Evaluation of Two New Chromogenic Media, CHROMagar MRSA and S. aureus ID, for Identifying Staphylococcus aureus and Screening Methicillin-Resistant S. aureus

    OpenAIRE

    Hedin, Göran; Fang, Hong

    2005-01-01

    Thirty-nine methicillin-resistant Staphylococcus aureus (MRSA) isolates with diverse genetic backgrounds and two reference strains were correctly identified as S. aureus on CHROMagar MRSA and S. aureus ID media. Growth inhibition on CHROMagar MRSA was noted. A combination of cefoxitin disk and S. aureus ID was found suitable for rapid MRSA screening.

  8. Genomic characterization of ribitol teichoic acid synthesis in Staphylococcus aureus: genes, genomic organization and gene duplication

    Directory of Open Access Journals (Sweden)

    Lu Lingyi

    2006-04-01

    Full Text Available Abstract Background Staphylococcus aureus or MRSA (Methicillin Resistant S. aureus, is an acquired pathogen and the primary cause of nosocomial infections worldwide. In S. aureus, teichoic acid is an essential component of the cell wall, and its biosynthesis is not yet well characterized. Studies in Bacillus subtilis have discovered two different pathways of teichoic acid biosynthesis, in two strains W23 and 168 respectively, namely teichoic acid ribitol (tar and teichoic acid glycerol (tag. The genes involved in these two pathways are also characterized, tarA, tarB, tarD, tarI, tarJ, tarK, tarL for the tar pathway, and tagA, tagB, tagD, tagE, tagF for the tag pathway. With the genome sequences of several MRSA strains: Mu50, MW2, N315, MRSA252, COL as well as methicillin susceptible strain MSSA476 available, a comparative genomic analysis was performed to characterize teichoic acid biosynthesis in these S. aureus strains. Results We identified all S. aureus tar and tag gene orthologs in the selected S. aureus strains which would contribute to teichoic acids sythesis.Based on our identification of genes orthologous to tarI, tarJ, tarL, which are specific to tar pathway in B. subtilis W23, we also concluded that tar is the major teichoic acid biogenesis pathway in S. aureus. Further analyses indicated that the S. aureus tar genes, different from the divergon organization in B. subtilis, are organized into several clusters in cis. Most interesting, compared with genes in B. subtilis tar pathway, the S. aureus tar specific genes (tarI,J,L are duplicated in all six S. aureus genomes. Conclusion In the S. aureus strains we analyzed, tar (teichoic acid ribitol is the main teichoic acid biogenesis pathway. The tar genes are organized into several genomic groups in cis and the genes specific to tar (relative to tag: tarI, tarJ, tarL are duplicated. The genomic organization of the S. aureus tar pathway suggests their regulations are different when

  9. An Aromatic Hydroxyamide Attenuates Multiresistant Staphylococcus aureus Toxin Expression.

    Science.gov (United States)

    Vomacka, Jan; Korotkov, Vadim S; Bauer, Bianca; Weinandy, Franziska; Kunzmann, Martin H; Krysiak, Joanna; Baron, Oliver; Böttcher, Thomas; Lorenz-Baath, Katrin; Sieber, Stephan A

    2016-01-26

    Methicillin-resistant Staphylococcus aureus (MRSA) causes severe infections with only few effective antibiotic therapies currently available. To approach this challenge, chemical entities with a novel and resistance-free mode of action are desperately needed. Here, we introduce a new hydroxyamide compound that effectively reduces the expression of devastating toxins in various S. aureus and MRSA strains. The molecular mechanism was investigated by transcriptome analysis as well as by affinity-based protein profiling. Down-regulation of several pathogenesis associated genes suggested the inhibition of a central virulence-related pathway. Mass spectrometry-based chemical proteomics revealed putative molecular targets. Systemic treatment with the hydroxyamide showed significant reduction of abscess sizes in a MRSA mouse skin infection model. The absence of resistance development in vitro further underlines the finding that targeting virulence could lead to prolonged therapeutic options in comparison to antibiotics that directly address bacterial survival.

  10. An Aromatic Hydroxyamide Attenuates Multiresistant Staphylococcus aureus Toxin Expression.

    Science.gov (United States)

    Vomacka, Jan; Korotkov, Vadim S; Bauer, Bianca; Weinandy, Franziska; Kunzmann, Martin H; Krysiak, Joanna; Baron, Oliver; Böttcher, Thomas; Lorenz-Baath, Katrin; Sieber, Stephan A

    2016-01-26

    Methicillin-resistant Staphylococcus aureus (MRSA) causes severe infections with only few effective antibiotic therapies currently available. To approach this challenge, chemical entities with a novel and resistance-free mode of action are desperately needed. Here, we introduce a new hydroxyamide compound that effectively reduces the expression of devastating toxins in various S. aureus and MRSA strains. The molecular mechanism was investigated by transcriptome analysis as well as by affinity-based protein profiling. Down-regulation of several pathogenesis associated genes suggested the inhibition of a central virulence-related pathway. Mass spectrometry-based chemical proteomics revealed putative molecular targets. Systemic treatment with the hydroxyamide showed significant reduction of abscess sizes in a MRSA mouse skin infection model. The absence of resistance development in vitro further underlines the finding that targeting virulence could lead to prolonged therapeutic options in comparison to antibiotics that directly address bacterial survival. PMID:26748534

  11. Osteoradionecrosis of the skull after radiation therapy for invasive carcinoma.

    Science.gov (United States)

    Nguyen, Michaela T; Billington, Alicia; Habal, Mutaz B

    2011-09-01

    Osteoradionecrosis (ORN) of the skull is a rare but fatal complication of radiation therapy for the treatment of head and neck malignancies. The pathogenesis of ORN follows the "3Hs Theory" proposed by Marx (J Oral Maxillofac Surg 1983;41:283-288) in which radiation induces tissue injury by causing vessel thrombosis (hypovascularity), which leads to hypoxia, and results in cell death of the skin and the underlying structure of the bony element (hypocellularity) including the deep visceral structures. This note details a patient with severe and extensive ORN of the parietooccipital region of the skull because of a large dose of radiation therapy for the treatment of an invasive basal cell carcinoma of the scalp. The patient's condition was further complicated by an extensive infection with methicillin-resistant Staphylococcus aureus, which leads to meningitis and cerebral edema as well as cerebritis. The patient was successfully treated with interdisciplinary medical and surgical aggressive therapy and radical procedures involving 4 separate trips to the operating room for an 18-month period. Success was achieved because of early clinical diagnosis of ORN, aggressive eradication of infected and necrotic tissues including the brain, and restoration of functioning and viable tissues through the use of local flaps to change an open wound to a closed wound. PMID:21959411

  12. Non-Monotonic Survival of Staphylococcus aureus with Respect to Ciprofloxacin Concentration Arises from Prophage-Dependent Killing of Persisters

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    Elizabeth L. Sandvik

    2015-11-01

    Full Text Available Staphylococcus aureus is a notorious pathogen with a propensity to cause chronic, non-healing wounds. Bacterial persisters have been implicated in the recalcitrance of S. aureus infections, and this motivated us to examine the persistence of S. aureus to ciprofloxacin, a quinolone antibiotic. Upon treatment of exponential phase S. aureus with ciprofloxacin, we observed that survival was a non-monotonic function of ciprofloxacin concentration. Maximal killing occurred at 1 µg/mL ciprofloxacin, which corresponded to survival that was up to ~40-fold lower than that obtained with concentrations ≥ 5 µg/mL. Investigation of this phenomenon revealed that the non-monotonic response was associated with prophage induction, which facilitated killing of S. aureus persisters. Elimination of prophage induction with tetracycline was found to prevent cell lysis and persister killing. We anticipate that these findings may be useful for the design of quinolone treatments.

  13. Improving transformation of Staphylococcus aureus belonging to the CC1, CC5 and CC8 clonal complexes.

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    Mary Janice Jones

    Full Text Available Methicillin resistant Staphylococcus aureus (MRSA is an opportunistic pathogen found in hospital and community environments that can cause serious infections. A major barrier to genetic manipulations of clinical isolates has been the considerable difficulty in transforming these strains with foreign plasmids, such as those from E. coli, in part due to the type I and IV Restriction Modification (R-M barriers. Here we combine a Plasmid Artificial Modification (PAM system with DC10B E. coli cells (dcm mutants to bypass the barriers of both type I and IV R-M of S. aureus, thus allowing E. coli plasmid DNA to be transformed directly into clinical MRSA strains MW2, N315 and LAC, representing three of the most common clonal complexes. Successful transformation of clinical S. aureus isolates with E. coli-derived plasmids should greatly increase the ability to genetically modify relevant S. aureus strains and advance our understanding of S. aureus pathogenesis.

  14. Virulence Factors and Antibiotic Susceptibility of Staphylococcus aureus Isolates in Ready-to-Eat Foods: Detection of S. aureus Contamination and a High Prevalence of Virulence Genes

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    Suat Moi Puah

    2016-02-01

    Full Text Available Staphylococcus aureus is one of the leading causes of food poisoning. Its pathogenicity results from the possession of virulence genes that produce different toxins which result in self-limiting to severe illness often requiring hospitalization. In this study of 200 sushi and sashimi samples, S. aureus contamination was confirmed in 26% of the food samples. The S. aureus isolates were further characterized for virulence genes and antibiotic susceptibility. A high incidence of virulence genes was identified in 96.2% of the isolates and 20 different virulence gene profiles were confirmed. DNA amplification showed that 30.8% (16/52 of the S. aureus carried at least one SE gene which causes staphylococcal food poisoning. The most common enterotoxin gene was seg (11.5% and the egc cluster was detected in 5.8% of the isolates. A combination of hla and hld was the most prevalent coexistence virulence genes and accounted for 59.6% of all isolates. Antibiotic resistance studies showed tetracycline resistance to be the most common at 28.8% while multi-drug resistance was found to be low at 3.8%. In conclusion, the high rate of S. aureus in the sampled sushi and sashimi indicates the need for food safety guidelines.

  15. Virulence Factors and Antibiotic Susceptibility of Staphylococcus aureus Isolates in Ready-to-Eat Foods: Detection of S. aureus Contamination and a High Prevalence of Virulence Genes.

    Science.gov (United States)

    Puah, Suat Moi; Chua, Kek Heng; Tan, Jin Ai Mary Anne

    2016-02-01

    Staphylococcus aureus is one of the leading causes of food poisoning. Its pathogenicity results from the possession of virulence genes that produce different toxins which result in self-limiting to severe illness often requiring hospitalization. In this study of 200 sushi and sashimi samples, S. aureus contamination was confirmed in 26% of the food samples. The S. aureus isolates were further characterized for virulence genes and antibiotic susceptibility. A high incidence of virulence genes was identified in 96.2% of the isolates and 20 different virulence gene profiles were confirmed. DNA amplification showed that 30.8% (16/52) of the S. aureus carried at least one SE gene which causes staphylococcal food poisoning. The most common enterotoxin gene was seg (11.5%) and the egc cluster was detected in 5.8% of the isolates. A combination of hla and hld was the most prevalent coexistence virulence genes and accounted for 59.6% of all isolates. Antibiotic resistance studies showed tetracycline resistance to be the most common at 28.8% while multi-drug resistance was found to be low at 3.8%. In conclusion, the high rate of S. aureus in the sampled sushi and sashimi indicates the need for food safety guidelines. PMID:26861367

  16. Immunogenicity of toxins during Staphylococcus aureus infection

    NARCIS (Netherlands)

    N.J. Verkaik (Nelianne); O. Dauwalder (Olivier); K. Antri (Kenza); I. Boubekri (Ilhem); C.P. de Vogel (Corné); C. Badiou (Cédric); M. Bes (Michèle); F. Vandenesch (François); M. Tazir (Mohammed); H. Hooijkaas (Herbert); H.A. Verbrugh (Henri); A.F. van Belkum (Alex); J. Etienne (Jerome); G. Lina (Gérard); N. Ramdani-Bouguessa (Nadjia); W.J.B. van Wamel (Willem)

    2010-01-01

    textabstractAB - BACKGROUND: Toxins are important Staphylococcus aureus virulence factors, but little is known about their immunogenicity during infection. Here, additional insight is generated. METHODS: Serum samples from 206 S. aureus-infected patients and 201 hospital-admitted control subjects we

  17. Population structure of Staphylococcus aureus in China

    NARCIS (Netherlands)

    Yan, Xiaomei

    2015-01-01

    The present PhD research was aimed at analysing the population structure of Staphylococcus aureus in China. Between 2000 and 2005 we found that patients from a single Chinese hospital showed increasing trends in antimicrobial resistance. Among methicillin-resistant S. aureus (MRSA), resistance again

  18. Correlation between fundamental binding forces and clinical prognosis of Staphylococcus aureus infections of medical implants

    Energy Technology Data Exchange (ETDEWEB)

    Yongsunthon, Ruchirej; Fowler, Vance; Lower, Brian H.; Vellano, Francis P.; Alexander, Emily; Reller, L. Barth; Corey, G. Ralph; Lower, Steven

    2007-02-01

    Implanted medical devices (e.g., prosthetic heart valves, permanent pacemakers) significantly improve the quality of life for many humans. However, a common clinical observation is that such devices become colonized with potentially life-threatening Staphylococcus aureus biofilms, which are difficult to combat with host defenses or antibiotics. This study attempts to draw a correlation between the clinical outcome of patients with implanted cardiac devices and the fundamental binding forces ultimately responsible for the initiation of an S. aureus biofilm in-situ. Atomic force microscopy was used to measure forces between a fibronectin-coated probe (simulating a prosthetic implant) and 15 different strains of S. aureus isolated from either patients with infected cardiac devices (invasive population) or healthy human subjects (control population). The fibronectin-coated probe was repeatedly brought into and out of contact with a bacterium’s surface, “fishing” for a reaction with the cell’s fibronectin-binding proteins. More than 40,000 force profiles were measured on 5-10 different cells for each of the 15 clinical strains. A unique force-signature was observed for a binding event between the fibronectin-coated probe and the bacteria. When grouped by the frequency of this force-signature, there was a strong distinction (p=0.01) between the invasive and control populations of S. aureus. This discovery suggests that biofilm forming bacteria may be classified according to their “force taxonomy”, which could have a positive effect on health care as it bridges the long-standing disconnect between macroscopic, clinical investigations and nanometer-scale forces ultimately responsible for a bond between S. aureus and the surface of a prosthetic device.

  19. Dietary Omega-3 Fatty Acids Increase Survival and Decrease Bacterial Load in Mice Subjected to Staphylococcus aureus-Induced Sepsis.

    Science.gov (United States)

    Svahn, Sara L; Ulleryd, Marcus A; Grahnemo, Louise; Ståhlman, Marcus; Borén, Jan; Nilsson, Staffan; Jansson, John-Olov; Johansson, Maria E

    2016-04-01

    Sepsis caused by Staphylococcus aureus is increasing in incidence. With the alarming use of antibiotics,S. aureus is prone to become methicillin resistant. Antibiotics are the only widely used pharmacological treatment for sepsis. Interestingly, mice fed high-fat diet (HFD) rich in polyunsaturated fatty acids have better survival of S. aureus-induced sepsis than mice fed HFD rich in saturated fatty acids (HFD-S). To investigate what component of polyunsaturated fatty acids, i.e., omega-3 or omega-6 fatty acids, exerts beneficial effects on the survival of S. aureus-induced sepsis, mice were fed HFD rich in omega-3 or omega-6 fatty acids for 8 weeks prior to inoculation with S. aureus Further, mice fed HFD-S were treated with omega-3 fatty acid metabolites known as resolvins. Mice fed HFD rich in omega-3 fatty acids had increased survival and decreased bacterial loads compared to those for mice fed HFD-S after S. aureus-induced sepsis. Furthermore, the bacterial load was decreased in resolvin-treated mice fed HFD-S after S. aureus-induced sepsis compared with that in mice treated with vehicle. Dietary omega-3 fatty acids increase the survival of S. aureus-induced sepsis by reversing the deleterious effect of HFD-S on mouse survival.

  20. Investigation of biofilm formation in clinical isolates of Staphylococcus aureus.

    Science.gov (United States)

    Cassat, James E; Smeltzer, Mark S; Lee, Chia Y

    2014-01-01

    Invasive methicillin-resistant Staphylococcus aureus (MRSA) infections are often characterized by recalcitrance to antimicrobial therapy, which is a function not only of widespread antimicrobial resistance among clinical isolates, but also the capacity to form biofilms. Biofilms consist of ordered populations of bacterial colonies encased in a polysaccharide and/or proteinaceous matrix. This unique physiologic adaptation limits penetration of antimicrobial molecules and innate immune effectors to the infectious focus, increasing the likelihood of treatment failure and progression to chronic infection. Investigation of mechanisms of biofilm formation and dispersal, as well as the physiologic adaptations to the biofilm lifestyle, is therefore critical to developing new therapies to combat MRSA infections. In this chapter, we describe two in vitro methods for the investigation of staphylococcal biofilm formation, a microtiter plate-based assay of biofilm formation under static conditions and a flow cell-based assay of biofilm formation under fluid shear. We also detail an in vivo murine model of catheter-associated biofilm formation that is amenable to imaging and microbiologic analyses. Special consideration is given to the conditions necessary to support biofilm formation by clinical isolates of S. aureus. PMID:24085698

  1. Retrospection of Alien Invasive Forest Insect Pests in China

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Eleven species of alien invasive forest insect pests have been found since the early time that insect species had been taken recorded in China. Their origins, inland distribution, invasive time, hosts, causing damage are recorded in this paper for the evidence of biological invasion. Their control methods are also studied or discussed.

  2. Invasive and non-invasive methods for cardiac output measurement

    Directory of Open Access Journals (Sweden)

    Lavdaniti M.

    2008-01-01

    Full Text Available The hemodynamic status monitoring of high-risk surgical patients and critically ill patients inIntensive Care Units is one of the main objectives of their therapeutic management. Cardiac output is one of the mostimportant parameters for cardiac function monitoring, providing an estimate of whole body perfusion oxygen deliveryand allowing for an understanding of the causes of high blood pressure. The purpose of the present review is thedescription of cardiac output measurement methods as presented in the international literature. The articles documentthat there are many methods of monitoring the hemodynamic status of patients, both invasive and non-invasive, themost popular of which is thermodilution. The invasive methods are the Fick method and thermodilution, whereasthe non-invasive methods are oeshophaegeal Doppler, transoesophageal echocardiography, lithium dilution, pulsecontour, partial CO2 rebreathing and thoracic electrical bioimpedance. All of them have their advantages and disadvantages,but thermodilution is the golden standard for critical patients, although it does entail many risks. The idealsystem for cardiac output monitoring would be non-invasive, easy to use, reliable and compatible in patients. A numberof research studies have been carried out in clinical care settings, by nurses as well as other health professionals, for thepurpose of finding a method of measurement that would have the least disadvantages. Nevertheless, the thermodilutiontechnique remains the most common approach in use today.

  3. The adherens junctions control susceptibility to Staphylococcus aureus α-toxin.

    Science.gov (United States)

    Popov, Lauren M; Marceau, Caleb D; Starkl, Philipp M; Lumb, Jennifer H; Shah, Jimit; Guerrera, Diego; Cooper, Rachel L; Merakou, Christina; Bouley, Donna M; Meng, Wenxiang; Kiyonari, Hiroshi; Takeichi, Masatoshi; Galli, Stephen J; Bagnoli, Fabio; Citi, Sandra; Carette, Jan E; Amieva, Manuel R

    2015-11-17

    Staphylococcus aureus is both a transient skin colonizer and a formidable human pathogen, ranking among the leading causes of skin and soft tissue infections as well as severe pneumonia. The secreted bacterial α-toxin is essential for S. aureus virulence in these epithelial diseases. To discover host cellular factors required for α-toxin cytotoxicity, we conducted a genetic screen using mutagenized haploid human cells. Our screen identified a cytoplasmic member of the adherens junctions, plekstrin-homology domain containing protein 7 (PLEKHA7), as the second most significantly enriched gene after the known α-toxin receptor, a disintegrin and metalloprotease 10 (ADAM10). Here we report a new, unexpected role for PLEKHA7 and several components of cellular adherens junctions in controlling susceptibility to S. aureus α-toxin. We find that despite being injured by α-toxin pore formation, PLEKHA7 knockout cells recover after intoxication. By infecting PLEKHA7(-/-) mice with methicillin-resistant S. aureus USA300 LAC strain, we demonstrate that this junctional protein controls disease severity in both skin infection and lethal S. aureus pneumonia. Our results suggest that adherens junctions actively control cellular responses to a potent pore-forming bacterial toxin and identify PLEKHA7 as a potential nonessential host target to reduce S. aureus virulence during epithelial infections.

  4. Biochemical and Molecular Analysis of Staphylococcus aureus Clinical Isolates from Hospitalized Patients

    Directory of Open Access Journals (Sweden)

    Amit Karmakar

    2016-01-01

    Full Text Available Staphylococcus aureus is opportunistic human as well as animal pathogen that causes a variety of diseases. A total of 100 Staphylococcus aureus isolates were obtained from clinical samples derived from hospitalized patients. The presumptive Staphylococcus aureus clinical isolates were identified phenotypically by different biochemical tests. Molecular identification was done by PCR using species specific 16S rRNA primer pairs and finally 100 isolates were found to be positive as Staphylococcus aureus. Screened isolates were further analyzed by several microbiological diagnostics tests including gelatin hydrolysis, protease, and lipase tests. It was found that 78%, 81%, and 51% isolates were positive for gelatin hydrolysis, protease, and lipase activities, respectively. Antibiogram analysis of isolated Staphylococcus aureus strains with respect to different antimicrobial agents revealed resistance pattern ranging from 57 to 96%. Our study also shows 70% strains to be MRSA, 54.3% as VRSA, and 54.3% as both MRSA and VRSA. All the identified isolates were subjected to detection of mecA, nuc, and hlb genes and 70%, 84%, and 40% were found to harbour mecA, nuc, and hlb genes, respectively. The current investigation is highly important and informative for the high level multidrug resistant Staphylococcus aureus infections inclusive also of methicillin and vancomycin.

  5. Regulation of Expression of Oxacillin-Inducible Methionine Sulfoxide Reductases in Staphylococcus aureus

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    Kyle R. Baum

    2015-01-01

    Full Text Available Cell wall-active antibiotics cause induction of a locus that leads to elevated synthesis of two methionine sulfoxide reductases (MsrA1 and MsrB in Staphylococcus aureus. To understand the regulation of this locus, reporter strains were constructed by integrating a DNA fragment consisting of the msrA1/msrB promoter in front of a promoterless lacZ gene in the chromosome of wild-type and MsrA1-, MsrB-, MsrA1/MsrB-, and SigB-deficient methicillin-sensitive S. aureus strain SH1000 and methicillin-resistant S. aureus strain COL. These reporter strains were cultured in TSB and the cellular levels of β-galactosidase activity in these cultures were assayed during different growth phases. β-galactosidase activity assays demonstrated that the lack of MsrA1, MsrB, and SigB upregulated the msrA1/msrB promoter in S. aureus strain SH1000. In S. aureus strain COL, the highest level of β-galactosidase activity was observed under the conditions when both MsrA1 and MsrB proteins were absent. The data suggest that the msrA1/msrB locus, in part, is negatively regulated by MsrA1, MsrB, and SigB in S. aureus.

  6. Effects of Fermented Sumach on the Formation of Slime Layer of Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Sahra Kırmusaoğlu

    2012-03-01

    Full Text Available Objective: Staphylococcus aureus (S. aureus is one of the most commonly isolated bacterial pathogens in hospitals, and the most frequent cause of nosocomial infections. Nosocomial staphylococcal foreign-body infections related to biofilm formation are a serious threat, demanding new therapeutic and preventive strategies. Implantation of intravenous catheters and surgical implantation of prosthetic implants carry a risk of infection. In order to prevent all these effects of biofilms, a study was designed to observe the possible antibacterial effect of sumach (Rhus coriaria on the biofilm formation of S. aureus. Material and Methods: The influence of varying concentrations of sumach on the formation of biofilms by 13 strains of Staphylococcus aureus was tested by a microelisa assay. Results: The significant differences between varying concentrations of sumach (0.1, 0.2, 0.5 and 1.0 µl/ml were observed in four methicillin resistant Staphylococcus aureus (MRSA and nine methicillin sensitive Staphylococcus aureus (MSSA (p<0.05. In bacteria, a dose-related decrease in the formation of slime, which is a major virulence factor of staphylococcal infections, was observed. Conclusion: In our study, using 0.1, 0.2, 0.5 and 1.0 µl/ml of sumach, thirteen strains lost, 17%, 22%, 28% and 48% respectively of their capacity to produce biofilms. Sumach, which is a herbal product, can decrease the formation of biofilm, which is a major virulence factor in staphylococcal infections.

  7. Activity of bacteriocins synthesized by Bacillus thuringiensis against Staphylococcus aureus isolates associated to bovine mastitis.

    Science.gov (United States)

    Barboza-Corona, José Eleazar; de la Fuente-Salcido, Norma; Alva-Murillo, Nayeli; Ochoa-Zarzosa, Alejandra; López-Meza, Joel E

    2009-07-01

    Antimicrobial therapy is a useful tool to control bovine mastitis caused by Staphylococcus aureus, as consequence an increase in staphylococci resistant cases has been registered. Alternative strategies are desirable and bacteriocins represent attractive control agents to prevent bovine mastitis. The aim of this work was to evaluate the activity of five bacteriocins synthesized by Bacillus thuringiensis against S. aureus isolates associated to bovine mastitis. Fifty S. aureus isolates were recovered from milk composite samples of 26 Holstein lactating cows from one herd during September 2007 to February 2008 in México and susceptibility of those isolates to 12 antibiotics and 5 bacteriocins from B. thuringiensis was evaluated. S. aureus isolates were mainly resistant to penicillin (92%), dicloxacillin (86%), ampicillin (74%) and erythromycin (74%); whereas susceptibility to gentamicin, trimethoprim and tetracycline was detected at, respectively, 92%, 88%, and 72%. All S. aureus isolates showed susceptibility to the five bacteriocins synthesized by B. thuringiensis, mainly to morricin 269 and kurstacin 287 followed by kenyacin 404, entomocin 420 and tolworthcin 524. Our results showed that S. aureus isolates had differences in the antimicrobial resistance patterns and were susceptible to bacteriocins produced by B. thuringiensis, which could be useful as an alternative method to control bovine mastitis. PMID:19359107

  8. Efek Antibakteri dari Rebusan Daun Sambiloto (Andrographis paniculata Nees dan Produk Herbal Sambiloto Terhadap Staphylococcus Aureus

    Directory of Open Access Journals (Sweden)

    Adriyan Sikumalay

    2016-01-01

    Full Text Available AbstrakSambiloto (Andrographis paniculata Nees merupakan tanaman obat yang memiliki berbagai khasiat, salah satunya sebagai antibakteri.  Staphylococcus aureus merupakan penyebab utama infeksi. Penggunaan Sambiloto di masyarakat saat ini mempunyai beberapa pilihan diantaranya dengan membuat rebusan langsung dari daun sambiloto ataupun dengan membeli produk herbal sambiloto yang dijual di pasaran. Tujuan penelitian ini adalah menentukan efek antibakteri dari rebusan daun sambiloto (Andrographis paniculata Nees dan produk herbal sambiloto terhadap Staphylococcus aureus. Jenis penelitian adalah eksperimental dengan sembilan kali pengulangan menggunakan metode difusi. Penelitian dilakukan di laboratorium Mikrobiologi Fakultas Kedokteran Universitas Andalas Padang dari Maret  sampai Desember 2014. Sambiloto diekstrak dengan metode infusum. Kontrol yang digunakan adalah amoksisilin. Hasil penelitian memperlihatkan tidak ada daerah bebas kuman di sekitar cakram disk yang telah mengandung sambiloto. Kesimpulan hasil ini ialah rebusan daun sambiloto (Andrographis paniculata Nees dan produk herbal sambiloto tidak mempunyai efek antibakteri terhadap Staphylococcus aureus.Kata kunci: sambiloto, staphylococcus aureus, infusum AbstractBitter (Andrographis paniculata Nees is a medicinal plant that have various benefits, such as an antibacterial. Staphylococcus aureus is a major cause of infection. The use of bitter in today's society has several options such as by making direct decoction of the leaves of bitter or by buying herbal products of bitter sold in the market. The objective  of this study was to determine the antibacterial effect of decocted leaf of bitter (Andrographis paniculata Nees and herbal products of bitter against Staphylococcus aureus.This type of research was experimental with nine repetitions using diffusion method. This research was conducted in the laboratory of Microbiology Faculty of Medicine Andalas University Padang in March to

  9. Community-acquired methicillin-resistant Staphylococcus aureus in Central Australia.

    Science.gov (United States)

    Stevens, Claire L; Ralph, Anna; McLeod, James E T; McDonald, Malcolm I

    2006-01-01

    To date, there has been scant information about the burden of methicillin-resistant Staphylococcus aureus infections in Central Australia. Our aims were to determine the proportion of Staphylococcus aureus infections due to methicillin-resistant strains in Central Australia, to characterise resistance to non-beta lactam antibiotics and to correlate findings with available demographic information. We retrospectively reviewed S. aureus isolates identified by the Microbiology Laboratory of the Pathology Department, Alice Springs Hospital between September 2005 and February 2006. Multi-resistance was defined as resistance to three or more non-beta lactam antibiotics. We identified the recovery site and extended antibiotic resistance profile of each isolate. Demographic data included place of residence, discharge diagnosis and ethnicity. There were 524 S. aureus isolates: 417 (79.6%) methicillin-sensitive S. aureus, 104 (19.7%) non-multi-resistant MRSA (nmrMRSA) and 3 (0.7%) multi-resistant MRSA (mrMRSA). MRSA accounted for 7/22 (32%) invasive infections and 91/474 (19.2%) cases of staphylococcal skin infections. Aboriginal people comprised 89 per cent (93/104) of patients with nmrMRSA; 57 per cent lived in remote communities, 21 per cent in suburban Alice Springs, and 18 per cent in Alice Springs Town Camps. Six per cent (6/104) of nmrMRSA were hospital-acquired. Of the nmrMRSA isolates, 57 per cent (59/104) were resistant to erythromycin and 7 per cent (7/104) to fusidic acid. All MRSA isolates were susceptible to co-trimoxazole. In conclusion, Central Australia has high rates of community-acquired nmrMRSA and low rates of multi-resistant MRSA. Erythromycin resistance in S. aureus is also common. These findings should prompt the review of antimicrobial prescribing guidelines for the region, especially for treatment of skin and soft tissue infections.

  10. Piperine Plays an Anti-Inflammatory Role in Staphylococcus aureus Endometritis by Inhibiting Activation of NF-κB and MAPK Pathways in Mice

    Directory of Open Access Journals (Sweden)

    Wen-jun Zhai

    2016-01-01

    Full Text Available Endometritis is commonly caused by pathogenic microorganisms, including Staphylococcus aureus (S. aureus. Piperine, which is a natural medicine, has shown a variety of biological activities. To explore the effect and mechanism of piperine on S. aureus endometritis, a mouse model of S. aureus endometritis was successfully established in the present study. Histopathological changes were observed with H&E staining, cytokines were analyzed by ELISA, mRNA was analyzed by qPCR, and proteins were detected by western blot. The results showed that piperine could significantly alleviate inflammatory injury in S. aureus endometritis. The qPCR and ELISA results showed that piperine effectively reduced the S. aureus-induced overexpression of TNF-α, IL-1β, and IL-6 but increased the expression of IL-10. The S. aureus-induced inflammation was related to TLR-2 and TLR-4 because the results showed that their expression was increased in S. aureus infection but then decreased with piperine treatment. To further confirm that piperine caused an anti-inflammatory response by targeting NF-κB and MAPKs, the expression of I-κB, p65, p38, ERK, and JNK was measured. The phosphorylation of I-κB, p65, p38, ERK, and JNK was inhibited by piperine in a dose-dependent manner. All of the results indicated that piperine may be a potential anti-inflammatory drug both in endometritis and in other S. aureus-induced diseases.

  11. Piperine Plays an Anti-Inflammatory Role in Staphylococcus aureus Endometritis by Inhibiting Activation of NF-κB and MAPK Pathways in Mice.

    Science.gov (United States)

    Zhai, Wen-Jun; Zhang, Zhen-Biao; Xu, Nian-Nian; Guo, Ying-Fang; Qiu, Changwei; Li, Cheng-Ye; Deng, Gan-Zhen; Guo, Meng-Yao

    2016-01-01

    Endometritis is commonly caused by pathogenic microorganisms, including Staphylococcus aureus (S. aureus). Piperine, which is a natural medicine, has shown a variety of biological activities. To explore the effect and mechanism of piperine on S. aureus endometritis, a mouse model of S. aureus endometritis was successfully established in the present study. Histopathological changes were observed with H&E staining, cytokines were analyzed by ELISA, mRNA was analyzed by qPCR, and proteins were detected by western blot. The results showed that piperine could significantly alleviate inflammatory injury in S. aureus endometritis. The qPCR and ELISA results showed that piperine effectively reduced the S. aureus-induced overexpression of TNF-α, IL-1β, and IL-6 but increased the expression of IL-10. The S. aureus-induced inflammation was related to TLR-2 and TLR-4 because the results showed that their expression was increased in S. aureus infection but then decreased with piperine treatment. To further confirm that piperine caused an anti-inflammatory response by targeting NF-κB and MAPKs, the expression of I-κB, p65, p38, ERK, and JNK was measured. The phosphorylation of I-κB, p65, p38, ERK, and JNK was inhibited by piperine in a dose-dependent manner. All of the results indicated that piperine may be a potential anti-inflammatory drug both in endometritis and in other S. aureus-induced diseases. PMID:27293467

  12. Novel antibiotics for the treatment of Staphylococcus aureus.

    Science.gov (United States)

    Ohlsen, Knut

    2009-11-01

    Staphylococcus aureus is a leading cause of nosocomial and community-acquired infection associated with significant morbidity and mortality. Antibiotic treatment of infections owing to S. aureus have become increasingly challenging as the pathogen has acquired a broad spectrum of antibiotic resistance mechanisms. In particular, emergence and spread of methicillin-resistant S. aureus (MRSA) progressed to a global health threat. The glycopeptides antibiotics vancomycin and teicoplanin have remained as the drugs of last resort for more than 20 years. Fortunately, in addition to the glycopeptides, several novel antibiotics including linezolid, daptomycin, tigecycline, quinupristin/dalfopristin and ceftobiprole acting against MRSA have been recently introduced into clinical practice broadening therapeutic options. Although the arsenal of antistaphylococcal drugs has filled up in recent years, the rate of MRSA infection continues to be high in most countries. This demands an ongoing search for new antibacterials and lead compounds as well as development of alternative therapies and faster diagnostics to ensure effective anti-staphylococcal therapy in the future. PMID:22112259

  13. Staphylococcus aureus Regulatory RNAs as Potential Biomarkers for Bloodstream Infections.

    Science.gov (United States)

    Bordeau, Valérie; Cady, Anne; Revest, Matthieu; Rostan, Octavie; Sassi, Mohamed; Tattevin, Pierre; Donnio, Pierre-Yves; Felden, Brice

    2016-09-01

    Staphylococcus aureus is a commensal bacterium and pathogen. Identifying biomarkers for the transition from colonization to disease caused by this organism would be useful. Several S. aureus small RNAs (sRNAs) regulate virulence. We investigated presence and expression of 8 sRNAs in 83 S. aureus strains from 42 patients with sepsis or septic shock and 41 asymptomatic colonized carriers. Small pathogenicity island sRNAs sprB and sprC were clade specific. Six sRNAs had variable expression not correlated with clinical status. Expression of RNAIII was lower in strains from septic shock patients than in strains from colonized patients. When RNAIII was associated with expression of sprD, colonizing strains could be discriminated from strains in patients with bloodstream infections, including patients with sepsis and septic shock. Isolates associated with colonization might have sRNAs with target expression different from those of disease isolates. Monitoring expression of RNAIII and sprD could help determine severity of bloodstream infections. PMID:27224202

  14. Staphylococcus aureus isolates from goat and sheep milk seem to be closely related and differ from isolates detected among bovine milk

    Directory of Open Access Journals (Sweden)

    Axel eMerz

    2016-03-01

    Full Text Available Dairy goat and sheep farms suffer severe economic losses due to intramammary infections, with S. aureus representing the main cause of clinical mastitis in small ruminants. In addition, S. aureus contamination of goat and sheep milk may cause staphylococcal food poisoning, as many traditional caprine and ovine milk products are not subjected to pasteurization. Data on virulence and antimicrobial resistance genes, as well as on the clonality of S. aureus detected in goat and sheep milk is scarce. Therefore, it was the aim of this study to determine i spa types and clonal complexes and ii virulence and resistance gene profiles of S. aureus isolated from goat and sheep milk. A total of 162 milk samples from sheep and goats presenting signs of an intramammary infection and 104 bulk milk samples were collected. While low prevalence rates of S. aureus were detected on single animal level, 46% of the bulk tank milk samples from small ruminants were positive for S. aureus. All isolates were spa typed and clonal complexes and virulence and resistance gene patterns were determined using a DNA microarray. Data from 49 S. aureus isolates was included in the statistical analysis and the construction of a SplitsTree. The analyzed isolates could be assigned to eleven clonal complexes, with the large majority of goat and sheep isolates being assigned to CC130 and CC133. The findings of this study suggest that S. aureus shows pronounced adaptation to small ruminants in general, but not to sheep or goats in particular. Although some common characteristics among S. aureus from caprine, ovine, and bovine milk samples were observed, S. aureus from small ruminants seem to form a distinct population. As 67% of the detected S. aureus strains exhibited at least one enterotoxin gene, many caprine or ovine raw milk products may be contaminated with low levels of enterotoxigenic S. aureus, stressing the importance of strict maintenance of the cold chain.

  15. Staphylococcus aureus Isolates from Goat and Sheep Milk Seem to Be Closely Related and Differ from Isolates Detected from Bovine Milk.

    Science.gov (United States)

    Merz, Axel; Stephan, Roger; Johler, Sophia

    2016-01-01

    Dairy goat and sheep farms suffer severe economic losses due to intramammary infections, with Staphylococcus aureus representing the main cause of clinical mastitis in small ruminants. In addition, S. aureus contamination of goat and sheep milk may cause staphylococcal food poisoning, as many traditional caprine and ovine milk products are not subjected to pasteurization. Data on virulence and antimicrobial resistance genes, as well as on the clonality of S. aureus detected in goat and sheep milk is scarce. Therefore, it was the aim of this study to determine (i) spa types and clonal complexes (CC) and (ii) virulence and resistance gene profiles of S. aureus isolated from goat and sheep milk. A total of 162 milk samples from sheep and goats presenting signs of an intramammary infection and 104 bulk milk samples were collected. While low prevalence rates of S. aureus was detected on single animal level, 46% of the bulk tank milk samples from small ruminants were positive for S. aureus. All isolates were spa typed and CC and virulence and resistance gene patterns were determined using a DNA microarray. Data from 49 S. aureus isolates was included in the statistical analysis and the construction of a SplitsTree. The analyzed isolates could be assigned to eleven CC, with the large majority of goat and sheep isolates being assigned to CC130 and CC133. The findings of this study suggest that S. aureus shows pronounced adaptation to small ruminants in general, but not to sheep or goats in particular. Although some common characteristics among S. aureus from caprine, ovine, and bovine milk samples were observed, S. aureus from small ruminants seem to form a distinct population. As 67% of the detected S. aureus strains exhibited at least one enterotoxin gene, many caprine, or ovine raw milk products may be contaminated with low levels of enterotoxigenic S. aureus, stressing the importance of strict maintenance of the cold chain. PMID:27014240

  16. Incidence of methicillin-resistant Staphylococcus aureus infection in a children's hospital in the Washington metropolitan area of the United States, 2003 – 2010

    OpenAIRE

    Song, Xiaoyan; Cogen, Jonathan; Singh, Nalini

    2013-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) has emerged as a major public health threat. In this retrospective cohort study, we included patients with laboratory-confirmed MRSA infections treated at Children's National Medical Center in Washington, District of Columbia between July 2003 and December 2010. The secular trends in the incidence rates of skin/soft tissue and invasive MRSA infections were assessed. Molecular analyses were performed on a subset of patients with invasive infec...

  17. 21 CFR 866.3700 - Staphylococcus aureus serological reagents.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Staphylococcus aureus serological reagents. 866... Staphylococcus aureus serological reagents. (a) Identification. Staphylococcus aureus serological reagents are... epidemiological information on these diseases. Certain strains of Staphylococcus aureus produce an...

  18. Analysis of 12 cases of severe sepsis caused by methicillin-resistant Staphylococcus aureus infections in children%儿童耐甲氧西林金黄色葡萄球菌感染致严重脓毒症12例分析

    Institute of Scientific and Technical Information of China (English)

    陈雨青; 金丹群; 卢松建

    2015-01-01

    Objective To analyze the clinical features and bacterial drug resistance of severe sepsis caused by methicil-lin-resistant Staphylococcus aureus (MRSA) infections in children. Methods The clinical data and results of antibiotic suscep-tibility test in 12 children with severe sepsis caused by MRSA infections from January 2010 to December 2013 were analyzed retrospectively. Results Among 12 children, there were 5 boys and 7 girls. Their age ranged from 8 days to 11 years, with a me-dian age of 1 year and there were 9 infants. All cases presented with acute onset which included 5 cases of acute osteomyelitis or purulent arthritis, 5 cases of necrotizing pneumonia with pyothorax, one case of necrotizing fasciitis and one case of bloodstream infection. 8 cases were complicated by skin and soft tissue infection, 7 cases by septic shock and 1 case by disseminated intravas-cular coagulation. The levels of C-reactive protein were increased in all children and white blood cell counts were decreased in 4 children. The susceptibility testing showed MRSA was sensitive to vancomycin and linezolid, and resistant to erythromycin, clin-damycin and compound sulfamethoxazole. After treatment with surgical debridement and closed-chest drainage, 8 cases survived and 4 cases died. Conclusions The severe sepsis caused by MRSA infections was common in infants with sudden onset and rapid progress, so active treatments are needed.%目的:分析儿童耐甲氧西林金黄色葡萄球菌(MRSA)感染导致严重脓毒症的临床特点及细菌耐药性。方法回顾性分析2010年1月至2013年12月收治的12例MRSA感染致严重脓毒症患儿的病史和细菌药敏试验资料。结果12例患儿中,男5例、女7例,年龄8 d~11岁,中位年龄1岁,9例为<1岁婴儿,均急性起病。5例表现为急性骨髓炎和/或化脓性关节炎,5例表现为坏死性肺炎伴脓胸,1例表现为坏死性筋膜炎,1例表现为血流感染;其中8例同时伴有皮肤及

  19. Current and emerging therapeutic modalities for hyperhidrosis, part 2: moderately invasive and invasive procedures.

    Science.gov (United States)

    Ram, Ramin; Lowe, Nicholas J; Yamauchi, Paul S

    2007-04-01

    Hyperhidrosis (HH) hinders patient quality of life and causes the secondary effect of excess cutaneous sweat. Treatment modalities include conservative and noninvasive therapies such as topical agents and iontophoresis. This article reviews moderately invasive and invasive procedures, such as botulinum toxin, curettage, and endoscopic thoracic sympathectomy (ETS), and compares their advantages and disadvantages in safety and efficacy. PMID:17500375

  20. Molecular Insights on the Transition of Non-invasive DCIS to Invasive ductal Carcinoma

    Institute of Scientific and Technical Information of China (English)

    Dihua YU

    2009-01-01

    @@ More than 90% of breast cancer-related deaths are caused by metastasis not primary tumor. To effectively reduce cancer mortality, it is extremely im-portant to predict the risk of, and to intervene in, the critical transition from non-invasive ductal carcinoma in situ (DCIS) to life-threatening invasive ductal carcinoma (IDC).

  1. The Heme Sensor System of Staphylococcus aureus

    OpenAIRE

    Stauff, Devin L; Skaar, Eric P.

    2009-01-01

    The important human pathogen Staphylococcus aureus is able to satisfy its nutrient iron requirement by acquiring heme from host hemoglobin in the context of infection. However, heme acquisition exposes S. aureus to heme toxicity. In order to detect the presence of toxic levels of exogenous heme, S. aureus is able to sense heme through the heme sensing system (HssRS) two-component system. Upon sensing heme, HssRS directly regulates the expression of the heme-regulated ABC transporter HrtAB, wh...

  2. Antibacterial Activity of New Oxazolidin-2-One Analogues in Methicillin-Resistant Staphylococcus aureus Strains

    Directory of Open Access Journals (Sweden)

    Jesús Córdova-Guerrero

    2014-03-01

    Full Text Available Staphylococcus aureus is one of the most common causes of nosocomial infections. The purpose of this study was the synthesis and in vitro evaluation of antimicrobial activity of 10 new 3-oxazolidin-2-one analogues on 12 methicillin resistant S. aureus (MRSA clinical isolates. S. aureus confirmation was achieved via catalase and coagulase test. Molecular characterization of MRSA was performed by amplification of the mecA gene. Antimicrobial susceptibility was evaluated via the Kirby-Bauer disc diffusion susceptibility test protocol, using commonly applied antibiotics and the oxazolidinone analogues. Only (R-5-((S-1-dibenzylaminoethyl-1,3-oxazolidin-2-one (7a exhibited antibacterial activity at 6.6 μg. These results, allow us to infer that molecules such as 7a can be potentially used to treat infections caused by MRSA strains.

  3. Community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA: molecular background, virulence, and relevance for public health

    Directory of Open Access Journals (Sweden)

    MF Bonesso

    2011-01-01

    Full Text Available Staphylococcus aureus and coagulase-negative Staphylococcus (CoNS are frequently found in nosocomial environments as the main pathogen in several infections. In 1961, reports of nosocomial S. aureus resistant to methicillin, the drug of choice against penicillin-resistant strains, required new alternatives and vancomycin started being used to treat infections caused by methicillin-resistant S. aureus (MRSA. Community-acquired methicillin-resistant S. aureus (CA-MRSA was first reported in 1990 affecting patients without risk factors for infection with MRSA of hospital origin. MRSA of community origin harbor the genes responsible for the synthesis of Panton-Valentine leukocidin (PVL, a toxin associated with skin and soft tissue infections and that carries the staphylococcal cassette chromosome mec (SCCmec type IV. CA-MRSA emergence has caused great impact on the worldwide medical community since the presence of this pathogen in patients without risk factors represents a high risk to public health.

  4. Antibiotic activity of the extract of Punica granatum Linn. over bovine strains of Staphylococcus aureus Atividade antimicrobiana do extrato de Punica granatum Linn. em linhagens de Staphylococcus aureus de origem bovina

    OpenAIRE

    Maria A. R. Silva; Jane S. Higino; Jozinete V. Pereira; José P. Siqueira-Júnior; Maria S.V. Pereira

    2008-01-01

    Human and veterinary medicines have not been so well succeeded in order to achieving their goals concerning the treatment of infections for long term caused by Staphylococcus aureus linked to resistance development against antibiotic agents. The antibiotic activity of the Punica granatum Linn. fresh fruit pericarp extract was evaluated by the agar diffusion method on 38 S. aureus strains, isolated from apparently healthy lactating cows in farms situated in counties of the semi-arid region of ...

  5. Drug-resistant human Staphylococcus aureus in sanctuary apes pose a threat to endangered wild ape populations.

    Science.gov (United States)

    Schaumburg, Frieder; Mugisha, Lawrence; Peck, Bruce; Becker, Karsten; Gillespie, Thomas R; Peters, Georg; Leendertz, Fabian H

    2012-12-01

    Reintroduction of sanctuary apes to natural habitat is considered an important tool for conservation; however, reintroduction has the potential to endanger resident wild apes through the introduction of human pathogens. We found a high prevalence of drug-resistant, human-associated lineages of Staphylococcus aureus in sanctuary chimpanzees (Pan troglodytes) from Zambia and Uganda. This pathogen is associated with skin and soft tissue diseases and severe invasive infections (i.e. pneumonia and septicemia). Colonization by this bacterium is difficult to clear due to frequent recolonization. In addition to its pathogenic potential, human-related S. aureus can serve as an indicator organism for the transmission of other potential pathogens like pneumococci or mycobacteria. Plans to reintroduce sanctuary apes should be reevaluated in light of the high risk of introducing human-adapted S. aureus into wild ape populations where treatment is impossible. PMID:22907634

  6. Laboratory Maintenance of Methicillin-Resistant Staphylococcus aureus (MRSA)

    OpenAIRE

    Nicholas P Vitko; Richardson, Anthony R.

    2013-01-01

    Staphylococcus aureus is an important bacterial pathogen in the hospital and community settings, especially Staphylococcus aureus clones that exhibit methicillin-resistance (MRSA). Many strains of S. aureus are utilized in the laboratory, underscoring the genetic differences inherent in clinical isolates. S. aureus grows quickly at 37°C with aeration in rich media (e.g. BHI) and exhibits a preference for glycolytic carbon sources. Furthermore, S. aureus has a gold pigmentation, exhibits β-hem...

  7. An update on the epidemiology, pathogenesis and management of infective endocarditis with emphasis on Staphylococcus aureus.

    Science.gov (United States)

    Tak, Tahir; Reed, Kurt D; Haselby, Ray C; McCauley, Charles S; Shukla, Sanjay K

    2002-01-01

    The incidence of infective endocarditis (IE) is thought to be around 4/100,000 person years in the general population, and 15/100,000 over the age of 50 years. The risk of acquiring IE is higher among patients with valvular heart disease (e.g., rheumatic valves, bicuspid aortic valves, myxomatous degeneration, etc.), congenital heart disease (e.g., coarctation, patent ductus arteriosus, ventricular septal defect, etc.), prosthetic cardiac valves, and among intravenous drug abusers. Staphylococcus aureus is one of the most common infective agents of IE, and most commonly originates from nosocomial sources, e.g., intravenous and arterial catheters, pacemaker leads, and prosthetic valves. Endocarditis caused by S aureus has a mortality rate of approximately 20% to 40%. In up to 40% of patients, IE caused by S aureus is associated with embolic complications. The risk of death increases with the development of complications. The epidemiology and microbiology of S aureus are changing rapidly, and resistance to antibiotics, especially methicillin, is becoming more widespread. In this review we will focus on the epidemiology, microbiology, and pathogenesis of S aureus IE, and also summarize the current guidelines for diagnosis, treatment, and prophylaxis of this clinical condition. PMID:12426917

  8. Staphylococcus aureus bacteremia: what is the impact of oxacillin resistance on mortality?

    Directory of Open Access Journals (Sweden)

    V.C. Cassettari

    2005-02-01

    Full Text Available In order to analyse the impact of oxacillin resistance on the mortality of Staphylococcus aureus bacteremia, and to assess the antimicrobial susceptibility of community-acquired strains in two large university hospitals (the Instituto do Coração do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo and the Instituto Central do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, we carried out a four-month-long prospective cohort study, which included 163 consecutive cases of S. aureus bacteremia. Of these, 140 (85.9% were hospital-acquired, 9 (5.5% were community-acquired and 14 (8.6% were of indeterminate origin. No cases of community-acquired infection by oxacillin-resistant S. aureus was identified. Among hospital-acquired infections, oxacillin-resistant S. aureus was responsible for 64.3% of cases. Mortality up to 15 days after diagnosis of bacteremia was 27% (18/67 for infections caused by susceptible strains and 33% (32/96 for infections caused by oxacillin-resistant strains (p=0.10. The following independent risk factors for the acquisition of oxacillin-resistant S. aureus were identified in multiple logistical regression analysis: age over 60 years, use of corticoids; presence of a central vascular catheter, and previous use of antibiotics.

  9. Filaments in curved flow: Rapid formation of Staphylococcus aureus biofilm streamers

    Science.gov (United States)

    Kim, Min Young; Drescher, Knut; Pak, On Shun; Bassler, Bonnie L.; Stone, Howard A.

    2014-03-01

    Biofilms are surface-associated conglomerates of bacteria that are highly resistant to antibiotics. These bacterial communities can cause chronic infections in humans by colonizing, for example, medical implants, heart valves, or lungs. Staphylococcus aureus, a notorious human pathogen, causes some of the most common biofilm-related infections. Despite the clinical importance of S. aureus biofilms, it remains mostly unknown how physical effects, in particular flow, and surface structure influence biofilm dynamics. Here we use model microfluidic systems to investigate how environmental factors, such as surface geometry, surface chemistry, and fluid flow affect biofilm development in S. aureus.We discovered that S. aureus rapidly forms flow-induced, filamentous biofilm streamers, and furthermore if surfaces are coated with human blood plasma, streamers appear within minutes and clog the channels more rapidly than if the channels are uncoated. To understand how biofilm streamer filaments reorient in curved flow to bridge the distances between corners, we developed a mathematical model based on resistive force theory and slender filaments. Understanding physical aspects of biofilm formation in S. aureus may lead to new approaches for interrupting biofilm formation of this pathogen.

  10. Filaments in curved streamlines: rapid formation of Staphylococcus aureus biofilm streamers

    Science.gov (United States)

    Kim, Minyoung Kevin; Drescher, Knut; Pak, On Shun; Bassler, Bonnie L.; Stone, Howard A.

    2014-06-01

    Biofilms are surface-associated conglomerates of bacteria that are highly resistant to antibiotics. These bacterial communities can cause chronic infections in humans by colonizing, for example, medical implants, heart valves, or lungs. Staphylococcus aureus, a notorious human pathogen, causes some of the most common biofilm-related infections. Despite the clinical importance of S. aureus biofilms, it remains mostly unknown how physical effects, in particular flow, and surface structure influence biofilm dynamics. Here we use model microfluidic systems to investigate how environmental factors, such as surface geometry, surface chemistry, and fluid flow affect biofilm development of S. aureus. We discovered that S. aureus rapidly forms flow-induced, filamentous biofilm streamers, and furthermore if surfaces are coated with human blood plasma, streamers appear within minutes and clog the channels more rapidly than if the channels are uncoated. To understand how biofilm streamer filaments reorient in flows with curved streamlines to bridge the distances between corners, we developed a mathematical model based on resistive force theory of slender filaments. Understanding physical aspects of biofilm formation of S. aureus may lead to new approaches for interrupting biofilm formation of this pathogen.

  11. Mastite com lesões sistêmicas por Staphylococus aureus subesp. aureus em coelhos

    OpenAIRE

    Traverso Sandra Davi; Cunha Leonardo da; Fernandes Joaquim César Teixeira; Loretti Alexandre Paulino; Rhoden Adriana; Wunder Jr. Elsio; Driemeier David

    2003-01-01

    Em uma criação composta por 1800 coelhos, 33% das matrizes apresentaram mastite e lesões cutâneas crostosas e purulentas. Estes animais apresentavam-se entre 10 a- 12 meses de idade e em segunda parição. Quinze coelhos afetados foram sacrificados e necropsiados. Na necropsia, além das lesões cutâneas haviam microabscessos em diversos órgãos. Das amostras coletadas isolou-se Staphylococcus aureus subesp. aureus. S. aureus subesp. aureus também foi isolado de "swab" nasal coletado do tratador e...

  12. Fibrinogen acts as a bridging molecule in the adherence of Staphylococcus aureus to cultured human endothelial cells.

    OpenAIRE

    Cheung, A L; Krishnan, M.; Jaffe, E A; Fischetti, V A

    1991-01-01

    The propensity of Staphylococcus aureus to cause acute endovascular infections during transient bacteremia is poorly understood. To examine the events leading to the attachment of staphylococci to endothelium, adherence assays were developed to study the role of blood factors in the mediation of staphylococcal adherence to cultured human umbilical vein endothelium in vitro. Results indicate that the preferential attachment of S. aureus to endothelial cells is mediated by fibrinogen adsorbed f...

  13. Phylogenetic Analysis of Staphylococcus aureus CC398 Reveals a Sub-Lineage Epidemiologically Associated with Infections in Horses

    DEFF Research Database (Denmark)

    Abdelbary, Mohamed M. H.; Wittenberg, Anne; Cuny, Christiane;

    2014-01-01

    -allelic polymorphisms, and phylogenetic analyses revealed that an epidemic sub-clone within CC398 (dubbed 'clade (C)') has spread within and between equine hospitals, where it causes nosocomial infections in horses and colonises the personnel. While clade (C) was strongly associated with S. aureus from horses...... in veterinary-care settings (p = 2x10(-7)), it remained extremely rare among S. aureus isolates from human infections....

  14. Phenotypes and Virulence among Staphylococcus aureus USA100, USA200, USA300, USA400, and USA600 Clonal Lineages

    OpenAIRE

    King, Jessica M.; Kulhankova, Katarina; Stach, Christopher S.; Vu, Bao G.; Salgado-Pabón, Wilmara

    2016-01-01

    ABSTRACT Staphylococcus aureus diseases affect ~500,000 individuals per year in the United States. Worldwide, the USA100, USA200, USA400, and USA600 lineages cause many of the life-threatening S. aureus infections, such as bacteremia, infective endocarditis, pneumonia, toxic shock syndrome, and surgical site infections. However, the virulence mechanisms associated with these clonal lineages, in particular the USA100 and USA600 isolates, have been severely understudied. We investigated the vir...

  15. Draft Genome Sequences of Staphylococcus aureus AMRF1 (ST22) and AMRF2 (ST672), Ocular Methicillin-Resistant Isolates

    KAUST Repository

    Velusamy, Nithya

    2014-03-20

    Sequence type 22 (ST22) and ST672 are the two major emerging clones of community-acquired methicillin-resistant Staphylococcus aureus in India. ST672 strains were found to cause severe ocular infections. We report the draft genome sequences of two emerging strains of methicillin-resistant S. aureus, AMRF1 (ST22) and AMRF2 (ST672), isolated from patients with ocular infections.

  16. Detection of enterotoxin genes of staphylococcus aureus isolates from chicken nugget in Esfahan province by PCR technique

    OpenAIRE

    Hajar Madahi; Ebrahim Rahimi; Mohammad Jalali

    2015-01-01

    Introduction: The enterotoxigenic Staphylococcus aureus is considered as one of the most common agents of food poisoning, gastroenteritis, diarrhea and vomiting that the presence of bacterial virulence genes can be as the most important cause of this foodborn illness. The present study was conducted to determine the presence of S. aureus and its virulence factors in chicken nugget and ready to eat foods in Iran. Materials and methods: In summer 2012 a total of 420 samples...

  17. Development of a biofilm inhibitor molecule against multidrug resistant Staphylococcus aureus associated with gestational urinary tract infections

    OpenAIRE

    Balamurugan, P.; Hema, M.; Kaur, Gurmeet; Sridharan, V.; Prabu, P. C.; Sumana, M. N.; Princy, S. Adline

    2015-01-01

    Urinary Tract Infection (UTI) is a globally widespread human infection caused by an infestation of uropathogens. Eventhough, Escherichia coli is often quoted as being the chief among them, Staphylococcus aureus involvement in UTI especially in gestational UTI is often understated. Staphylococcal accessory regulator A (SarA) is a quorum regulator of S. aureus that controls the expression of various virulence and biofilm phenotypes. Since SarA had been a focussed target for antibiofilm agent de...

  18. The Impact of CodY on Virulence Determinant Production in Community-Associated Methicillin Resistant Staphylococcus aureus

    OpenAIRE

    Rivera, Frances E.; Miller, Halie K.; Kolar, Stacey L; Stevens, Stanley M.; Shaw, Lindsey N.

    2011-01-01

    Staphylococcus aureus is a leading human pathogen of both hospital and community-associated diseases worldwide. This organism causes a wealth of infections within the human host as a result of the vast arsenal of toxins encoded within its genome. Previous transcriptomic studies have shown that toxin production in S. aureus can be strongly impacted by the negative regulator CodY. CodY acts by directly, and indirectly (via Agr), repressing toxin production during times of plentif...

  19. Changes in Holstein cow milk and serum proteins during intramammary infection with three different strains of Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Robert Claude

    2011-09-01

    Full Text Available Abstract Background Staphylococcus aureus is one of the most prevalent pathogens to cause mastitis in dairy cattle. Intramammary infection of dairy cows with S. aureus is often subclinical, due to the pathogen's ability to evade the innate defense mechanisms, but this can lead to chronic infection. A sub-population of S. aureus, known as small colony variant (SCV, displays atypical phenotypic characteristics, causes persistent infections, and is more resistant to antibiotics than parent strains. Therefore, it was hypothesized that the host immune response will be different for SCV than its parental or typical strains of S. aureus. In this study, the local and systemic immune protein responses to intramammary infection with three strains of S. aureus, including a naturally occurring bovine SCV strain (SCV Heba3231, were characterized. Serum and casein-depleted milk cytokine levels (interleukin-8, interferon-γ, and transforming growth factor-β1, as well as serum haptoglobin concentrations were monitored over time after intramammary infection with each of the three S. aureus strains. Furthermore, comparative proteomics was used to evaluate milk proteome profiles during acute and chronic phases of S. aureus intramammary infection. Results Serum IL-8, IFN-γ, and TGF-β1 responses differed in dairy cows challenged with different strains of S. aureus. Changes in overall serum haptoglobin concentrations were observed for each S. aureus challenge group, but there were no significant differences observed between groups. In casein-depleted milk, strain-specific differences in the host IFN-γ response were observed, but inducible IL-8 and TGF-β1 concentrations were not different between groups. Proteomic analysis of the milk following intramammary infection revealed unique host protein expression profiles that were dependent on the infecting strain as well as phase of infection. Notably, the protein, component-3 of the proteose peptone (CPP3, was

  20. Staphylococcus aureus spa type t437

    DEFF Research Database (Denmark)

    Glasner, C; Pluister, G; Westh, H;

    2015-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) belonging to the multilocus sequence type clonal complex 59 (MLST CC59) is the predominant community-associated MRSA clone in Asia. This clone, which is primarily linked with the spa type t437, has so far only been reported in low numbers among...... large epidemiological studies in Europe. Nevertheless, the overall numbers identified in some Northern European reference laboratories have increased during the past decade. To determine whether the S. aureus t437 clone is present in other European countries, and to assess its genetic diversity across...... Europe, we analysed 147 S. aureus t437 isolates from 11 European countries collected over a period of 11 years using multiple locus variable number tandem repeat fingerprinting/analysis (MLVF/MLVA) and MLST. Additionally 16 S. aureus t437 isolates from healthy carriers and patients from China were...

  1. Construction of a Multiplex Promoter Reporter Platform to Monitor Staphylococcus aureus Virulence Gene Expression and the Identification of Usnic Acid as a Potent Suppressor of psm Gene Expression.

    Science.gov (United States)

    Gao, Peng; Wang, Yanli; Villanueva, Iván; Ho, Pak Leung; Davies, Julian; Kao, Richard Yi Tsun

    2016-01-01

    As antibiotic resistance becomes phenomenal, alternative therapeutic strategies for bacterial infections such as anti-virulence treatments have been advocated. We have constructed a total of 20 gfp-luxABCDE dual-reporter plasmids with selected promoters from S. aureus virulence-associated genes. The plasmids were introduced into various S. aureus strains to establish a gfp-lux based multiplex promoter reporter platform for monitoring S. aureus virulence gene expressions in real time to identify factors or compounds that may perturb virulence of S. aureus. The gene expression profiles monitored by luminescence correlated well with qRT-PCR results and extrinsic factors including carbon dioxide and some antibiotics were shown to suppress or induce the expression of virulence factors in this platform. Using this platform, sub-inhibitory ampicillin was shown to be a potent inducer for the expression of many virulence factors in S. aureus. Bacterial adherence and invasion assays using mammalian cells were employed to measure S. aureus virulence induced by ampicillin. The platform was used for screening of natural extracts that perturb the virulence of S. aureus and usnic acid was identified to be a potent repressor for the expression of psm. PMID:27625639

  2. Transmissible mupirocin resistance in Staphylococcus aureus.

    OpenAIRE

    Rahman, M.; Noble, W. C.; Cookson, B

    1989-01-01

    The spread of two strains of Staphylococcus aureus with high level resistance to mupirocin is described. The resistance proved to be easily transferred to other S. aureus strains by filter mating experiments and on the skin of mice. No plasmid band corresponding to the resistance could be demonstrated by agarose gel electrophoresis or by caesium chloride gradient centrifugation but cleavage of 'chromosomal' DNA from resistant recipients showed bright bands of DNA absent from sensitive controls.

  3. Peptides from Tetraspanin CD9 Are Potent Inhibitors of Staphylococcus Aureus Adherence to Keratinocytes.

    Science.gov (United States)

    Ventress, Jennifer K; Partridge, Lynda J; Read, Robert C; Cozens, Daniel; MacNeil, Sheila; Monk, Peter N

    2016-01-01

    Staphylococcus aureus is one of the primary causative agents of skin and wound infections. As bacterial adherence is essential for infection, blocking this step can reduce invasion of host tissues by pathogens. An anti-adhesion therapy, based on a host membrane protein family, the tetraspanins, has been developed that can inhibit the adhesion of S. aureus to human cells. Synthetic peptides derived from a keratinocyte-expressed tetraspanin, CD9, were tested for anti-adhesive properties and at low nanomolar concentrations were shown to inhibit bacterial adhesion to cultured keratinocytes and to be effective in a tissue engineered model of human skin infection. These potential therapeutics had no effect on keratinocyte viability, migration or proliferation, indicating that they could be a valuable addition to current treatments for skin infection. PMID:27467693

  4. Antibacterial effect of silver nanoparticles along with protein synthesis-inhibiting antibiotics on Staphylococcus aureus isolated from cattle mastitis

    Directory of Open Access Journals (Sweden)

    Malahat Ahmadi

    2014-01-01

    Full Text Available Introduction: Staphylococcus aureus is an opportunistic pathogen in dairy ruminants which is also found in healthy carriage and can be a major cause of mastitis. Various mastitis control programs have been used to combat the problem but have not always been efficient. In most countries, antibiotic resistance is extremely common. Silver nanoparticles have shown antimicrobial activity against S. aureus. In the present study the effect of silver nanoparticles on S. aureus isolated from cattle mastitis along with antibiotics of operative on protein bacterial synthesis investigated. Materials and methods: Three hundred eleven milk samples were collected from the cow farms. Each milk sample was cultured on mannitol salt agar and was incubated. A total of 72 isolates of S. aureus were isolated from the bovine mastitis milk samples. S. aureus DNA extracted by DNA purification kit according to the manufacturer protocol. 58 isolates were confirmed as S. aureus by biochemical tests as well as nuc gene detection. MIC and MBC determined for silver nanoparticles with antibiotics on 50 isolates. Results: The resistance of S. aureus isolates against erythromycin, gentamicin, streptomycin and doxycycline were 100, 22, 100 and 8%, respectively. 8 of all isolates were sensitive to 25 µg/ml concentration of silver nanoparticles. The 92% growth of the samples were inhibited at concentrations between 50-100 µg/ml. Discussion and conclusion: The present study suggests that antibiotics which can inhibit protein synthesis have significant synergistic effect along with silver nanoparticles.

  5. Detection of Staphylococcus aureus by polymerase chain reaction amplification of the nuc gene.

    Science.gov (United States)

    Brakstad, O G; Aasbakk, K; Maeland, J A

    1992-07-01

    Synthetic oligonucleotide primers of 21 and 24 bases, respectively, were used in the polymerase chain reaction (PCR) to amplify a sequence of the nuc gene, which encodes the thermostable nuclease of Staphylococcus aureus. A DNA fragment of approximately 270 bp was amplified from lysed S. aureus cells or isolated DNA. The PCR product was detected by agarose gel electrophoresis or Southern blot analysis by using a 33-mer internal nuc gene hybridization probe. With S. aureus cells the lower detection limit was less than 10 CFU, and with the isolated target the lower detection limit was 0.69 pg of DNA. The primers recognized 90 of 90 reference or clinical S. aureus strains. Amplification was not recorded when 80 strains representing 16 other staphylococcal species were tested or when 20 strains representing 9 different nonstaphylococcal species were tested. Some of the non-S. aureus staphylococci produced thermostable nucleases but were PCR negative. The PCR product was generated when in vitro-cultured S. aureus was used to prepare simulated clinical specimens of blood, urine, cerebrospinal fluid, or synovial fluid. No PCR product was generated when the sterile body fluids were tested. However, the sensitivity of the PCR was reduced when S. aureus in blood or urine was tested in comparison with that when bacteria in saline were tested. With the bacteria in blood, the detection limit of the PCR was 10(3) CFU. A positive PCR result was recorded when a limited number of clinical samples from wounds verified to be infected with S. aureus were tested, while the PCR product was not detected in materials from infections caused by other bacteria. Generation of PCR products was not affected by exposure of S. aureus to bactericidal agents, including cloxacillin and gentamicin, prior to testing, but was affected by exposure to UV radiation. The PCR for amplification of the nuc gene has potential for the rapid diagnosis of S. aureus infections by direct testing of clinical

  6. The effectiveness of bacteriophages against methicillin-resistant Staphylococcus aureus ST398 nasal colonization in pigs

    NARCIS (Netherlands)

    Verstappen, Koen M.; Tulinski, Pawel; Duim, Birgitta; Fluit, Ad C.; Carney, Jennifer; Nes, Van Arie; Wagenaar, Jaap A.

    2016-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is an important colonizer in animals and an opportunistic pathogen in humans. In humans, MRSA can cause infections that might be difficult to treat because of antimicrobial resistance. The use of bacteriophages has been suggested as a potential a

  7. Adaptive immune response to lipoproteins of Staphylococcus aureus in healthy subjects

    NARCIS (Netherlands)

    Vu, Chi Hai; Kolata, Julia; Stentzel, Sebastian; Beyer, Anica; Salazar, Manuela Gesell; Steil, Leif; Pané-Farré, Jan; Rühmling, Vanessa; Engelmann, Susanne; Götz, Friedrich; van Dijl, Jan Maarten; Hecker, Michael; Mäder, Ulrike; Schmidt, Frank; Völker, Uwe; Bröker, Barbara M

    2016-01-01

    Staphylococcus aureus is a frequent commensal but also a dangerous pathogen, causing many forms of infection ranging from mild to life-threatening conditions. Among its virulence factors are lipoproteins, which are anchored in the bacterial cell membrane. Lipoproteins perform various functions in co

  8. The Epidemiology of Methicillin-Resistant Staphylococcus aureus (MRSA) in Germany

    NARCIS (Netherlands)

    Koeck, Robin; Mellmann, Alexander; Schaumburg, Frieder; Friedrich, Alexander W.; Kipp, Frank; Becker, Karsten

    2011-01-01

    Background: For decades, methicillin-resistant Staphylococcus aureus (MRSA) has been a major cause of infection in hospitals and nursing homes (health care-associated MRSA, HA-MRSA). Beginning in the late 1990s, many countries have also experienced a rising incidence of MRSA infection outside of the

  9. Staphylococcus aureus Endocarditis as a Complication of Toxocariasis-Associated Endomyocarditis With Fibrosis: A Case Report

    Science.gov (United States)

    Kuenzli, Esther; Labhardt, Niklaus; Balestra, Gianmarco; Weisser, Maja; Zellweger, Michael J.; Blum, Johannes

    2016-01-01

    Complications associated with Toxocara canis infection are rare. We present a case of a patient with Staphylococcus aureus endocarditis as a complication of an endomyocardial fibrosis caused by T canis. The epidemiological, pathological, and clinical features of this rare complication are described here.

  10. Outcome of Community-Acquired Staphylococcus aureus Bacteraemia in Patients with Diabetes

    DEFF Research Database (Denmark)

    Smit, Jesper; Thomsen, RW; Schønheyder, Henrik Carl;

    2016-01-01

    BACKGROUND: Patients with diabetes (DM) experience increased risk of Staphylococcus aureus bacteraemia (SAB), but the prognostic impact of diabetes in patients with SAB remain unclear. Therefore, we investigated 30-day all-cause mortality in patients with and without DM. METHODS: Population...

  11. Linezolid Resistance in Staphylococcus aureus: Gene Dosage Effect, Stability, Fitness Costs, and Cross-Resistances▿

    OpenAIRE

    Besier, Silke; Ludwig, Albrecht; Zander, Johannes; Brade, Volker; Wichelhaus, Thomas A.

    2008-01-01

    Linezolid resistance in Staphylococcus aureus is typically associated with mutations in the 23S rRNA gene. Here we show that the accumulation of a single point mutation, G2576T, in the different copies of this gene causes stepwise increases in resistance, impairment of the biological fitness, and cross-resistance to quinupristin-dalfopristin and chloramphenicol.

  12. [FDG-PET/CT: a valuable technique in Staphylococcus aureus bacteraemia

    NARCIS (Netherlands)

    Bleeker-Rovers, C.P.; Vos, F.J.; Oyen, W.J.G.

    2015-01-01

    Staphylococcus aureus bacteraemia is often complicated by metastatic infectious foci. Some of these metastatic foci do not cause any localizing symptoms, which complicates early detection and adequate treatment. Where localizing symptoms are absent FDG-PET/CT is highly useful as a screening method f

  13. Spredning af Staphylococcus aureus ved nasal bærertilstand

    DEFF Research Database (Denmark)

    Iskandar, Aline; Nguyen, Ngan; Kolmos, Hans Jørn

    2009-01-01

    INTRODUCTION: Staphylococcus aureus (Sa) is an important cause of hospital-acquired infections, and nasal carriage of Sa is common among health care workers. This study was designed to measure the airborne dispersal of Sa and other bacteria from such carriers and to investigate whether the use of.......g. inserting central venous catheters. Udgivelsesdato: 2009-Feb-2...

  14. Preventing Community-Associated Methicillin-Resistant "Staphylococcus aureus" among Student Athletes

    Science.gov (United States)

    Many, Patricia S.

    2008-01-01

    Methicillin-resistant "Staphylococcus aureus" (MRSA) was once thought to be a bacterium causing infections in only hospitalized patients. However, a new strain of MRSA has emerged among healthy individuals who have not had any recent exposure to a hospital or to medical procedures. This new strain is known as "community-associated MRSA". Studies…

  15. Staphylococcus aureus Manganese Transport Protein C (MntC) Is an Extracellular Matrix- and Plasminogen-Binding Protein

    Science.gov (United States)

    Salazar, Natália; Castiblanco-Valencia, Mónica Marcela; da Silva, Ludmila Bezerra; de Castro, Íris Arantes; Monaris, Denize; Masuda, Hana Paula; Barbosa, Angela Silva; Arêas, Ana Paula Mattos

    2014-01-01

    Infections caused by Staphylococcus aureus – particularly nosocomial infections - represent a great concern. Usually, the early stage of pathogenesis consists on asymptomatic nasopharynx colonization, which could result in dissemination to other mucosal niches or invasion of sterile sites, such as blood. This pathogenic route depends on scavenging of nutrients as well as binding to and disrupting extracellular matrix (ECM). Manganese transport protein C (MntC), a conserved manganese-binding protein, takes part in this infectious scenario as an ion-scavenging factor and surprisingly as an ECM and coagulation cascade binding protein, as revealed in this work. This study showed a marked ability of MntC to bind to several ECM and coagulation cascade components, including laminin, collagen type IV, cellular and plasma fibronectin, plasminogen and fibrinogen by ELISA. The MntC binding to plasminogen appears to be related to the presence of surface-exposed lysines, since previous incubation with an analogue of lysine residue, ε-aminocaproic acid, or increasing ionic strength affected the interaction between MntC and plasminogen. MntC-bound plasminogen was converted to active plasmin in the presence of urokinase plasminogen activator (uPA). The newly released plasmin, in turn, acted in the cleavage of the α and β chains of fibrinogen. In conclusion, we describe a novel function for MntC that may help staphylococcal mucosal colonization and establishment of invasive disease, through the interaction with ECM and coagulation cascade host proteins. These data suggest that this potential virulence factor could be an adequate candidate to compose an anti-staphylococcal human vaccine formulation. PMID:25409527

  16. Staphylococcus aureus manganese transport protein C (MntC is an extracellular matrix- and plasminogen-binding protein.

    Directory of Open Access Journals (Sweden)

    Natália Salazar

    Full Text Available Infections caused by Staphylococcus aureus--particularly nosocomial infections--represent a great concern. Usually, the early stage of pathogenesis consists on asymptomatic nasopharynx colonization, which could result in dissemination to other mucosal niches or invasion of sterile sites, such as blood. This pathogenic route depends on scavenging of nutrients as well as binding to and disrupting extracellular matrix (ECM. Manganese transport protein C (MntC, a conserved manganese-binding protein, takes part in this infectious scenario as an ion-scavenging factor and surprisingly as an ECM and coagulation cascade binding protein, as revealed in this work. This study showed a marked ability of MntC to bind to several ECM and coagulation cascade components, including laminin, collagen type IV, cellular and plasma fibronectin, plasminogen and fibrinogen by ELISA. The MntC binding to plasminogen appears to be related to the presence of surface-exposed lysines, since previous incubation with an analogue of lysine residue, ε-aminocaproic acid, or increasing ionic strength affected the interaction between MntC and plasminogen. MntC-bound plasminogen was converted to active plasmin in the presence of urokinase plasminogen activator (uPA. The newly released plasmin, in turn, acted in the cleavage of the α and β chains of fibrinogen. In conclusion, we describe a novel function for MntC that may help staphylococcal mucosal colonization and establishment of invasive disease, through the interaction with ECM and coagulation cascade host proteins. These data suggest that this potential virulence factor could be an adequate candidate to compose an anti-staphylococcal human vaccine formulation.

  17. Infertility as a consequence of spermagglutinating Staphylococcus aureus colonization in genital tract of female mice.

    Directory of Open Access Journals (Sweden)

    Siftjit Kaur

    Full Text Available Various studies have shown Staphylococcus aureus to be one of the most prevalent organism in male and female genital tract but most practitioners dismiss it as mere contamination which is assumed to be of no significance. However, it is now suggested that the presence of this organism should not be ignored, as incubation of spermatozoa with S. aureus results in reduced sperm motility. Although S. aureus has been reported to cause immobilization of spermatozoa, however, its role in infertility has yet to be elucidated. The present study was designed to establish a spermagglutinating strain of S. aureus isolated from the cervix of a woman with unexplained infertility, in mouse and evaluate its effect on fertility outcome. Female Balb/c mice were inoculated intravaginally with different doses of S. aureus (10(4, 10(6 or 10(8cfu/20 µl for 10 consecutive days. Microbial colonization monitored every 3(rd day by vaginal cultures, revealed that strain could efficiently colonize mouse vagina. Mating on day 12, with proven breeder males led to 100% decrease in fertility as compared to control. Even a single dose of 10(6 or 10(8cfu could lead to vaginal colonization which persisted for 10 days followed by gradual clearing till 21 days, vaginal cultures were negative thereafter. Female mice mated on day 7 (culture positive, were rendered infertile, however, the mice mated on day 22 (culture negative, retained fertility and delivered pups indicating its role in provoking infertility. Further, except infertility, no other clinical manifestation could be seen apparently or histologically. However, when a non-spermagglutinating/immobilizing standard strain of S. aureus MTCC6625 was inoculated intravaginally at 10(8cfu for 10 days followed by mating on day 12, fertility was observed in all the female mice. This supports the hypothesis that infertility observed in the former groups was as a result of colonization with spermagglutinating strain of S. aureus.

  18. Antimicrobial susceptibility of canine and human Staphylococcus aureus collected in Saskatoon, Canada.

    Science.gov (United States)

    Rubin, J E; Chirino-Trejo, M

    2011-11-01

    Staphylococcus aureus is one of the most common causes of infection in people and is increasingly recognized in dogs. The increasing prevalence of methicillin resistant S. aureus (MRSA) is complicating the treatment of these infections. Panton Valentine leukocidin (PVL), a toxin involved in the pathogenesis of necrotic syndromes in people may be partially responsible for the rise of MRSA. Canine and human S. aureus from the same geographic area are genetically similar, indicating a common population and likely transmission. The implications of increasing antimicrobial resistance complicated by interspecies transmission, necessitates including both dogs and humans in S. aureus resistance surveillance studies. A collection of 126 S. aureus isolates from people (n = 99) and dogs (n = 27) were included, minimum inhibitor concentrations to a panel of 33 antimicrobials used in human and veterinary medicine were determined. No resistance to vancomycin, linezolid, daptomycin, quinupristin/dalfopristin or nitrofurantoin was found. A wide range of antibiograms were found; including resistance to 0-12 drugs (0-6 drug classes). Outstanding antibiograms included a canine MRSA resistant to rifampin and a human MRSA resistant to chloramphenicol. Inducible clindamycin resistance was found among 78% and 4% of canine and human MRSA and 17% and 25% of canine colonizing and human methicillin susceptible S. aureus (MSSA), respectively. Resistance to mupirocin was only found among human isolates including 20% of MRSA and 4% of MSSA. While no canine isolates were PVL positive, 39% of human MRSA and 2% of MSSA carried the gene. The bidirectional transmission of S. aureus between people and dogs necessitates the inclusion of isolates from both species in future studies. PMID:21824346

  19. The Surface Protein Pls of Methicillin-Resistant Staphylococcus aureus Is a Virulence Factor in Septic Arthritis

    OpenAIRE

    Josefsson, Elisabet; Juuti, Katri; Bokarewa, Maria; Kuusela, Pentti

    2005-01-01

    Pls, a surface protein of certain methicillin-resistant Staphylococcus aureus strains, is associated with poor bacterial adherence to solid-phase fibronectin and immunoglobulin G, as well as with reduced invasion of cultured epithelial cells. Here the importance of Pls for the development of septic arthritis and sepsis was investigated by using a mouse model. Mice inoculated with a pls knockout mutant developed a much milder arthritis and showed less grave weight reduction than mice infected ...

  20. Carotenoid Formation by Staphylococcus aureus

    Science.gov (United States)

    Hammond, Ray K.; White, David C.

    1970-01-01

    The carotenoid pigments of Staphylococcus aureus U-71 were identified as phytoene; ζ-carotene; δ-carotene; phytofluenol; a phytofluenol-like carotenoid, rubixanthin; and three rubixanthin-like carotenoids after extraction, saponification, chromatographic separation, and determination of their absorption spectra. There was no evidence of carotenoid esters or glycoside ethers in the extract before saponification. During the aerobic growth cycle the total carotenoids increased from 45 to 1,000 nmoles per g (dry weight), with the greatest increases in the polar, hydroxylated carotenoids. During the anaerobic growth cycle, the total carotenoids increased from 20 nmoles per g (dry weight) to 80 nmoles per g (dry weight), and only traces of the polar carotenoids were formed. Light had no effect on carotenoid synthesis. About 0.14% of the mevalonate-2-14C added to the culture was incorporated into the carotenoids during each bacterial doubling. The total carotenoids did not lose radioactivity when grown in the absence of 14C for 2.5 bacterial doublings. The total carotenoids did not lose radioactivity when grown in the absence of 14C for 2.5 bacterial doublings. The incorporation and turnover of 14C indicated the carotenes were sequentially desaturated and hydroxylated to form the polar carotenoids. PMID:5423369

  1. Staphylococcus aureus α-Toxin: Nearly a Century of Intrigue

    Directory of Open Access Journals (Sweden)

    Bryan J. Berube

    2013-06-01

    Full Text Available Staphylococcus aureus secretes a number of host-injurious toxins, among the most prominent of which is the small β-barrel pore-forming toxin α-hemolysin. Initially named based on its properties as a red blood cell lytic toxin, early studies suggested a far greater complexity of α-hemolysin action as nucleated cells also exhibited distinct responses to intoxication. The hemolysin, most aptly referred to as α-toxin based on its broad range of cellular specificity, has long been recognized as an important cause of injury in the context of both skin necrosis and lethal infection. The recent identification of ADAM10 as a cellular receptor for α-toxin has provided keen insight on the biology of toxin action during disease pathogenesis, demonstrating the molecular mechanisms by which the toxin causes tissue barrier disruption at host interfaces lined by epithelial or endothelial cells. This review highlights both the historical studies that laid the groundwork for nearly a century of research on α-toxin and key findings on the structural and functional biology of the toxin, in addition to discussing emerging observations that have significantly expanded our understanding of this toxin in S. aureus disease. The identification of ADAM10 as a proteinaceous receptor for the toxin not only provides a greater appreciation of truths uncovered by many historic studies, but now affords the opportunity to more extensively probe and understand the role of α-toxin in modulation of the complex interaction of S. aureus with its human host.

  2. Emergence of community-associated methicillin-resistant Staphylococcus aureus associated with pediatric infection in Cambodia.

    Directory of Open Access Journals (Sweden)

    Kheng Chheng

    Full Text Available BACKGROUND: The incidence of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA infection is rising in the developed world but appears to be rare in developing countries. One explanation for this difference is that resource poor countries lack the diagnostic microbiology facilities necessary to detect the presence of CA-MRSA carriage and infection. METHODOLOGY AND PRINCIPAL FINDINGS: We developed diagnostic microbiology capabilities at the Angkor Hospital for Children, Siem Reap, western Cambodia in January 2006 and in the same month identified a child with severe community-acquired impetigo caused by CA-MRSA. A study was undertaken to identify and describe additional cases presenting between January 2006 and December 2007. Bacterial isolates underwent molecular characterization using multilocus sequence typing, staphylococcal cassette chromosome mec (SCCmec typing, and PCR for the presence of the genes encoding Panton-Valentine Leukocidin (PVL. Seventeen children were identified with CA-MRSA infection, of which 11 had skin and soft tissue infection and 6 had invasive disease. The majority of cases were unrelated in time or place. Molecular characterization identified two independent MRSA clones; fifteen isolates were sequence type (ST 834, SCCmec type IV, PVL gene-negative, and two isolates were ST 121, SCCmec type V, PVL gene-positive. CONCLUSIONS: This represents the first ever report of MRSA in Cambodia, spread of which would pose a significant threat to public health. The finding that cases were mostly unrelated in time or place suggests that these were sporadic infections in persons who were CA-MRSA carriers or contacts of carriers, rather than arising in the context of an outbreak.

  3. Molecular epidemiology and antimicrobial resistance of methicillin-resistant Staphylococcus aureus bloodstream isolates in Taiwan, 2010.

    Directory of Open Access Journals (Sweden)

    Chih-Jung Chen

    Full Text Available The information of molecular characteristics and antimicrobial susceptibility pattern of methicillin-resistant Staphylococcus aureus (MRSA is essential for control and treatment of diseases caused by this medically important pathogen. A total of 577 clinical MRSA bloodstream isolates from six major hospitals in Taiwan were determined for molecular types, carriage of Panton-Valentine leukocidin (PVL and sasX genes and susceptibilities to 9 non-beta-lactam antimicrobial agents. A total of 17 genotypes were identified in 577 strains by pulsotyping. Five major pulsotypes, which included type A (26.2%, belonging to sequence type (ST 239, carrying type III staphylococcal chromosomal cassette mec (SCCmec, type F (18.9%, ST5-SCCmecII, type C (18.5%, ST59-SCCmecIV, type B (12.0%, ST239-SCCmecIII and type D (10.9%, ST59-SCCmecVT/IV, prevailed in each of the six sampled hospitals. PVL and sasX genes were respectively carried by ST59-type D strains and ST239 strains with high frequencies (93.7% and 99.1%, respectively but rarely detected in strains of other genotypes. Isolates of different genotypes and from different hospitals exhibited distinct antibiograms. Multi-resistance to ≥3 non-beta-lactams was more common in ST239 isolates (100% than in ST5 isolates (97.2%, P = 0.0347 and ST59 isolates (8.2%, P<0.0001. Multivariate analysis further indicated that the genotype, but not the hospital, was an independent factor associated with muti-resistance of the MRSA strains. In conclusion, five common MRSA clones with distinct antibiograms prevailed in the major hospitals in Taiwan in 2010. The antimicrobial susceptibility pattern of invasive MRSA was mainly determined by the clonal distribution.

  4. What is minimally invasive dentistry?

    Science.gov (United States)

    Ericson, Dan

    2004-01-01

    Minimally Invasive Dentistry is the application of "a systematic respect for the original tissue." This implies that the dental profession recognizes that an artifact is of less biological value than the original healthy tissue. Minimally invasive dentistry is a concept that can embrace all aspects of the profession. The common delineator is tissue preservation, preferably by preventing disease from occurring and intercepting its progress, but also removing and replacing with as little tissue loss as possible. It does not suggest that we make small fillings to restore incipient lesions or surgically remove impacted third molars without symptoms as routine procedures. The introduction of predictable adhesive technologies has led to a giant leap in interest in minimally invasive dentistry. The concept bridges the traditional gap between prevention and surgical procedures, which is just what dentistry needs today. The evidence-base for survival of restorations clearly indicates that restoring teeth is a temporary palliative measure that is doomed to fail if the disease that caused the condition is not addressed properly. Today, the means, motives and opportunities for minimally invasive dentistry are at hand, but incentives are definitely lacking. Patients and third parties seem to be convinced that the only things that count are replacements. Namely, they are prepared to pay for a filling but not for a procedure that can help avoid having one.

  5. Complete Genome Sequence of the Quality Control Strain Staphylococcus aureus subsp. aureus ATCC 25923.

    Science.gov (United States)

    Treangen, Todd J; Maybank, Rosslyn A; Enke, Sana; Friss, Mary Beth; Diviak, Lynn F; Karaolis, David K R; Koren, Sergey; Ondov, Brian; Phillippy, Adam M; Bergman, Nicholas H; Rosovitz, M J

    2014-01-01

    Staphylococcus aureus subsp. aureus ATCC 25923 is commonly used as a control strain for susceptibility testing to antibiotics and as a quality control strain for commercial products. We present the completed genome sequence for the strain, consisting of the chromosome and a 27.5-kb plasmid. PMID:25377701

  6. Complete Genome Sequence of the Quality Control Strain Staphylococcus aureus subsp. aureus ATCC 25923

    OpenAIRE

    Todd J. Treangen; Maybank, Rosslyn A.; Enke, Sana; Friss, Mary Beth; Diviak, Lynn F.; Karaolis, David K. R.; Koren, Sergey; Ondov, Brian; Phillippy, Adam M.; Bergman, Nicholas H.; Rosovitz, M. J.

    2014-01-01

    Staphylococcus aureus subsp. aureus ATCC 25923 is commonly used as a control strain for susceptibility testing to antibiotics and as a quality control strain for commercial products. We present the completed genome sequence for the strain, consisting of the chromosome and a 27.5-kb plasmid.

  7. 万古霉素治疗耐甲氧西林金黄色葡萄球菌肺炎老年患者的疗效分析%Efficacy of vancomycin in treatment of pneumonia caused by methicillin-resistant Staphylococcus aureus in the elderly patients

    Institute of Scientific and Technical Information of China (English)

    陈红; 李小惠; 李为民; 陈勃江

    2015-01-01

    目的:探讨万古霉素治疗耐甲氧西林金黄色葡萄球菌(M RS A )肺炎老年患者的疗效和安全性。方法回顾性分析M RS A肺炎老年患者40例,根据治疗方案,将患者分为2组:万古霉素组25例,给予万古霉素每次0.5 g ,每8小时1次,静脉滴注,治疗时间10~14 d;利奈唑胺组15例,给予利奈唑胺每次0.6 g ,每12小时1次,静脉滴注,治疗时间10~14 d。比较两组患者的疗效和不良反应。结果万古霉素组临床有效率为72.0%,利奈唑胺组为86.7%,两组比较差异无统计学意义(P>0.05);经治疗后,万古霉素组MRSA清除率为76.0%,利奈唑胺组为80.0%,两组比较差异无统计学意义(P>0.05);利奈唑胺组有3例发生血小板减少>25%,占20.0%,万古霉素组未见血小板减少,万古霉素组有4例发生急性肾功能不全,占16.0%,利奈唑胺组未见肾功能损害。结论万古霉素治疗老年M RS A肺炎有较好的临床疗效,血小板减少的发生率低,应警惕急性肾功能不全的风险。%Objective To examine the efficacy and safety profile of vancomycin in treatment of pneumonia caused by methicillin‐resistant Staphylococcus aureus (MRSA)in the elderly patients .Methods The clinical data were retrospectively analyzed for 40 elderly patients with MRSA‐induced pneumonia .The patients were analyzed in terms of treatment regimen ,vancomycin (n=25)or linezolid (n= 15) .Vancomycin was administered intravenously at dose of 0 .5 g every 8 hours for 10‐14 days ,while linezolid was given intravenously at dose of 0 .6 g every 12 hours for 10‐14 days .The clinical efficacy and adverse events were compared between the two groups .Results The overall efficacy rate was 72 .0% in vancomycin group ,and 86 .7% in linezolid group (P>0 .05) .After treatment ,the clearance rate of MRSA was 76 .0% in vancomycin group ,and 80 .0% in linezolid group (P>0

  8. A variant epidemic methicillin resistant Staphylococcus aureus-15 cavernous sinus thrombosis and meningitis: A rare occurrence with unusual presentation

    Directory of Open Access Journals (Sweden)

    Veena Kumari H

    2010-01-01

    Full Text Available Septic cavernous sinus thrombosis (CST is an uncommon clinical syndrome. Although Staphylococcus aureus (S aureus is the most common bacterial pathogen causing CST, it is infrequent as a cause of meningitis. We report the first case of CST and meningitis from Bengaluru, Karnataka, caused by community-acquired epidemic methicillin resistant Staphylococcus aureus-15 (EMRSA-15, in a previously healthy individual without known risk factors; the patient recovered following treatment with vancomycin. The isolate was genotyped as belonging to staphylococcal cassette chromosome mec type IV and sequence type 22 and carried the panton-valentine leucocidin gene. It is the first Indian EMRSA-15 disease isolate from a case of meningitis. EMRSA-15 has been a major problem in hospitals in UK and it is a cause for great concern in Indian hospitals too.

  9. Duplex real-time PCR assay for rapid identification of Staphylococcus aureus isolates from dairy cow milk.

    Science.gov (United States)

    Pilla, Rachel; Snel, Gustavo G M; Malvisi, Michela; Piccinini, Renata

    2013-05-01

    Staphylococcus aureus isolates from dairy cow mastitis are not always consistent with the characteristic morphology described, and molecular investigation is often needed. The aim of the study was to develop a duplex real-time PCR assay for rapid identification of Staph. aureus isolates, targeting both nuc and Sa442. Overall, 140 isolates collected from dairy cow mastitis in 90 different herds, were tested. All strains had been identified using morphological and biochemical characteristics. DNA from each strain was amplified in real-time PCR assay, to detect nuc or Sa442. Thereafter, a duplex real-time PCR assay was performed, and specificity of the amplified products was assessed by high resolution melting curve analysis. Out of 124 Staph. aureus isolates, 33 did not show the typical morphology or enzymic activity; in 118 strains, the two melt-curve peaks consistent with nuc and Sa442 were revealed, while 2 isolates showed only the peak consistent with Sa442. Four isolates bacteriologically identified as Staph. aureus, were PCR-negative and were further identified as Staph. pseudintermedius by sequencing. Staph. pseudintermedius and coagulase-negative staphylococci did not carry nuc or Sa442. The results showed the correct identification of all isolates, comprehending also coagulase-or nuc-negative Staph. aureus, while other coagulase-positive Staphylococci were correctly identified as non-Staph. aureus. Both sensitivity and specificity were 100%. High resolution melting analysis allowed easy detection of unspecific products. Finally, the duplex real-time PCR was applied directly to 40 milk samples, to detect infected mammary quarters. The assay confirmed the results of bacteriological analysis, on Staph. aureus-positive or-negative samples. Therefore, the proposed duplex real-time PCR could be used in laboratory routine as a cost-effective and powerful tool for high-throughput identification of atypical Staph. aureus isolates causing dairy cow mastitis. Also, it

  10. Insights into invasion and restoration ecology: Time to collaborate towards a holistic approach to tackle biological invasions

    Directory of Open Access Journals (Sweden)

    Mirijam Gaertner

    2012-02-01

    Full Text Available The aim of our study is to provide an integrated framework for the management of alien plant invasions, combining insights and experiences from the fields of invasion and restoration ecology to enable more effective management of invasive species. To determine linkages between the scientific outputs of the two disciplines we used an existing data base on restoration studies between 2000 and 2008 and did a bibliometric analysis. We identified the type of restoration applied, determined by the aim of the study, and conducted a content analysis on 208 selected studies with a link to biological invasions (invasion-restoration studies. We found a total of 1075 articles on ecosystem restoration, with only eight percent of the studiesthe main objective to control alien invasions. The content analysis of 208 invasion-restoration studies showed that the majority of the studies focused on causes of degradation other than alien invasions. If invaders were referred to as the main driver of degradation, the prevalent cause for degradation was invaders outcompeting and replacing native species. Mechanical control of alien plant invasions was by far the most common control method used. Measures that went beyond the removal of alien plants were implemented in sixty-five percent of the studies.Although invasion control was not as common as other types of restoration, a closer look at the sub-group of invasion-restoration studies shows a clear link between restoration and invasion ecology. Concerns, as identified in the literature review, are firstly that restoration activities mostly focus on controlling the invader while other underlying causes for degradation are neglected, and secondly that the current approach of dealing with alien invasions lacks a combination of theoretical and practical aspects. We suggest that closer collaboration between invasion and restoration ecologists can help to improve the management of alien plant invasions. We conclude with a

  11. Staphylokinase Control of Staphylococcus aureus Biofilm Formation and Detachment Through Host Plasminogen Activation.

    Science.gov (United States)

    Kwiecinski, Jakub; Peetermans, Marijke; Liesenborghs, Laurens; Na, Manli; Björnsdottir, Halla; Zhu, Xuefeng; Jacobsson, Gunnar; Johansson, Bengt R; Geoghegan, Joan A; Foster, Timothy J; Josefsson, Elisabet; Bylund, Johan; Verhamme, Peter; Jin, Tao

    2016-01-01

    Staphylococcus aureus biofilms, a leading cause of persistent infections, are highly resistant to immune defenses and antimicrobial therapies. In the present study, we investigated the contribution of fibrin and staphylokinase (Sak) to biofilm formation. In both clinical S. aureus isolates and laboratory strains, high Sak-producing strains formed less biofilm than strains that lacked Sak, suggesting that Sak prevents biofilm formation. In addition, Sak induced detachment of mature biofilms. This effect depended on plasminogen activation by Sak. Host-derived fibrin, the main substrate cleaved by Sak-activated plasminogen, was a major component of biofilm matrix, and dissolution of this fibrin scaffold greatly increased susceptibility of biofilms to antibiotics and neutrophil phagocytosis. Sak also attenuated biofilm-associated catheter infections in mouse models. In conclusion, our results reveal a novel role for Sak-induced plasminogen activation that prevents S. aureus biofilm formation and induces detachment of existing biofilms through proteolytic cleavage of biofilm matrix components.

  12. Association between phage types and antimicrobial resistance among bovine isolates of Staphylococcus aureus in 10 countries

    DEFF Research Database (Denmark)

    Vintov, J.; Aarestrup, Frank Møller; Zinn, C. E.;

    2003-01-01

    associated with penicillin resistance in contrast to phage group I (P = 0.0023) and phage complex-80 (P = 0.0066). This study confirms that a large number of phage types of S. aureus cause bovine mastitis, but that some types predominate. In addition, these findings could indicate that the use of penicillin...... in the bovine environment has selected for specific types of S. aureus in countries with a high frequency of resistance. (C) 2003 Elsevier B.V. All rights reserved.......This study was conducted to investigate the diversity of phage types and associations between penicillin resistance and phage types among 815 Staphylococcus aureus isolates from bovine mastitis in nine European countries and USA. All isolates were examined for susceptibility to antimicrobial agents...

  13. Association between phage types and antimicrobial resistance among bovine Staphylococcus aureus from 10 countries

    DEFF Research Database (Denmark)

    Vintov, J.; Aarestrup, Frank Møller; Zinn, C. E.;

    2003-01-01

    associated with penicillin resistance in contrast to phage group I (P = 0.0023) and phage complex-80 (P = 0.0066). This study confirms that a large number of phage types of S. aureus cause bovine mastitis, but that some types predominate. In addition, these findings could indicate that the use of penicillin...... in the bovine environment has selected for specific types of S. aureus in countries with a high frequency of resistance.......This study was conducted to investigate the diversity of phage types and associations between penicillin resistance and phage types among 815 Staphylococcus aureus isolates from bovine mastitis in nine European countries and USA. All isolates were examined for susceptibility to antimicrobial agents...

  14. Treating Central Catheter-Associated Bacteremia Due to Methicillin-Resistant Staphylococcus aureus: Beyond Vancomycin.

    Science.gov (United States)

    Holt, Shannon; Thompson-Brazill, Kelly A; Sparks, E Ryan; Lipetzky, Juliana

    2016-08-01

    Methicillin-resistant Staphylococcus aureus is a frequent cause of hospital-associated infections, including central catheter-associated bacteremia. Vancomycin has been the drug of choice for treating this type of bacteremia for decades in patients who have no contraindications to the antibiotic. However, resistance to vancomycin is an emerging problem. Newer antibiotics approved by the Food and Drug Administration have activity against methicillin-resistant S aureus Some of the antibiotics also have activity against strains of S aureus that are intermediately susceptible or resistant to vancomycin. This article uses a case study to highlight the clinical signs of vancomycin failure and describes the indications for and appropriate use of alternative antimicrobials such as ceftaroline, daptomycin, linezolid, tigecycline, and telavancin. (Critical Care Nurse 2016;36[4]:46-57). PMID:27481801

  15. Effects of prophylactic administration of bacteriophages to immunosuppressed mice infected with Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Borysowski Jan

    2009-08-01

    Full Text Available Abstract Background Bacteriophages can be successfully applied to treat infections caused by antibiotic-resistant bacteria. Until now no attempts have been undertaken to treat infections in immunosuppressed patients with phages. In this work we investigated the prophylactic efficacy of specific bacteriophages in CBA mice treated with cyclophosphamide (CP and infected with Staphylococcus aureus. Results High numbers of bacterial colony-forming units in the organs as well as elevated tumor necrosis factor and interleukin-6 serum concentrations in CP-treated and S. aureus-infected mice were significantly lowered upon application of phages. The phages markedly increased the percentage of circulating neutrophils and immature cells from the myelocytic and lymphocytic lineages in CP-treated, S. aureus-infected mice as well as of myelocytes and immature neutrophils in the bone marrow. In addition, phages stimulated in such mice generation of specific agglutinins against S. aureus. Conclusion Application of specific phages to immunosuppressed mice prior to infection with S. aureus proved very effective, suggesting a potential benefit of phage therapy in immunocompromised patients experiencing bacterial infections.

  16. Biofilm formation by Staphylococcus aureus isolates from skin and soft tissue infections.

    Science.gov (United States)

    Kwiecinski, Jakub; Kahlmeter, Gunnar; Jin, Tao

    2015-05-01

    Many diseases caused by Staphylococcus aureus are associated with biofilm formation. However, the ability of S. aureus isolates from skin and soft tissue infections to form biofilms has not yet been investigated. We tested 160 isolates from patients with various skin infections for biofilm-forming capacity in different growth media. All the isolates formed biofilms, the extent of which depended on the type of growth medium. The thickest biofilms were formed when both plasma and glucose were present in the broth; in this case, S. aureus incorporated host fibrin into the biofilm's matrix. There were no differences in the biofilm formation between isolates from different types of skin infections, except for a particularly good biofilm formation by isolates from diabetic wounds and a weaker biofilm formation by isolates from impetigo. In conclusion, biofilm formation is a universal behavior of S. aureus isolates from skin infections. In some cases, such as in diabetic wounds, a particularly strong biofilm formation most likely contributes to the chronic and recurrent character of the infection. Additionally, as S. aureus apparently uses host fibrin as part of the biofilm structure, we suggest that plasma should be included more frequently in in vitro biofilm studies.

  17. IsdB-dependent hemoglobin binding is required for acquisition of heme by Staphylococcus aureus.

    Science.gov (United States)

    Pishchany, Gleb; Sheldon, Jessica R; Dickson, Claire F; Alam, Md Tauqeer; Read, Timothy D; Gell, David A; Heinrichs, David E; Skaar, Eric P

    2014-06-01

    Staphylococcus aureus is a Gram-positive pathogen responsible for tremendous morbidity and mortality. As with most bacteria, S. aureus requires iron to cause disease, and it can acquire iron from host hemoglobin. The current model for staphylococcal hemoglobin-iron acquisition proposes that S. aureus binds hemoglobin through the surface-exposed hemoglobin receptor IsdB. IsdB removes heme from bound hemoglobin and transfers this cofactor to other proteins of the Isd system, which import and degrade heme to release iron in the cytoplasm. Here we demonstrate that the individual components of the Isd system are required for growth on low nanomolar concentrations of hemoglobin as a sole source of iron. An in-depth study of hemoglobin binding by IsdB revealed key residues that are required for hemoglobin binding. Further, we show that these residues are necessary for heme extraction from hemoglobin and growth on hemoglobin as a sole iron source. These processes are found to contribute to the pathogenicity of S. aureus in a murine model of infection. Together these results build on the model for Isd-mediated hemoglobin binding and heme-iron acquisition during the pathogenesis of S. aureus infection.

  18. Screening of Molecular Virulence Markers in Staphylococcus aureus and Pseudomonas aeruginosa Strains Isolated from Clinical Infections

    Directory of Open Access Journals (Sweden)

    Veronica Lazar

    2010-12-01

    Full Text Available Staphylococcus (S. aureus and Pseudomonas (Ps. aeruginosa are two of the most frequently opportunistic pathogens isolated in nosocomial infections, responsible for severe infections in immunocompromised hosts. The frequent emergence of antibiotic-resistant S. aureus and Ps. aeruginosa strains has determined the development of new strategies in order to elucidate the different mechanisms used by these bacteria at different stages of the infectious process, providing the scientists with new procedures for preventing, or at least improving, the control of S. aureus and Ps. aeruginosa infections. The purpose of this study was to characterize the molecular markers of virulence in S. aureus and Ps. aeruginosa strains isolated from different clinical specimens. We used multiplex and uniplex PCR assays to detect the genes encoding different cell-wall associated and extracellular virulence factors, in order to evaluate potential associations between the presence of putative virulence genes and the outcome of infections caused by these bacteria. Our results demonstrate that all the studied S. aureus and Ps. aeruginosa strains synthesize the majority of the investigated virulence determinants, probably responsible for different types of infections.

  19. Novel inhibitors of Staphylococcus aureus virulence gene expression and biofilm formation.

    Directory of Open Access Journals (Sweden)

    Yibao Ma

    Full Text Available Staphylococcus aureus is a major human pathogen and one of the more prominent pathogens causing biofilm related infections in clinic. Antibiotic resistance in S. aureus such as methicillin resistance is approaching an epidemic level. Antibiotic resistance is widespread among major human pathogens and poses a serious problem for public health. Conventional antibiotics are either bacteriostatic or bacteriocidal, leading to strong selection for antibiotic resistant pathogens. An alternative approach of inhibiting pathogen virulence without inhibiting bacterial growth may minimize the selection pressure for resistance. In previous studies, we identified a chemical series of low molecular weight compounds capable of inhibiting group A streptococcus virulence following this alternative anti-microbial approach. In the current study, we demonstrated that two analogs of this class of novel anti-virulence compounds also inhibited virulence gene expression of S. aureus and exhibited an inhibitory effect on S. aureus biofilm formation. This class of anti-virulence compounds could be a starting point for development of novel anti-microbial agents against S. aureus.

  20. Effect of ethanolic extract of Ecballium elaterium against Staphylococcus aureus and Candida albicans

    Institute of Scientific and Technical Information of China (English)

    Ghaleb Adwan; Yousef Salameh; Kamel Adwan

    2011-01-01

    To evaluate the antimicrobial activity of ethanolic extract of Ecballium elaterium (E.elaterium) fruits alone against Staphylococcus aureus (S. aureus) strains and Candida albicans (C. albicans) strains, or in combination with penicillin against Staphylococcus areus strains. Methods: Evaluation of the antimicrobial activity or synergy interaction was carried out using microdilution method. Results: The results showed that ethanolic extract of E. elaterium fruits has antimicrobial activity against methicillin resistant S. aureus (MRSA), methicillin sensitive S.aureus (MSSA) and C. albicans. This extract showed a significant decrease in minimum inhibitory concentrations (MIC) of penicillin against both MRSA and MSSA strains. Fractional inhibitory concentration index (FIC) between penicillin and ethanolic extract of E. elaterium fruits against these test strains was less than 0.5. Conclusions: This study suggests that ethanolic extract of E. elaterium fruits has antimicrobial activity against S. aureus and C. albicans and there is a possibility of concurrent use of penicillin and E. elaterium extract in combination in the treatment of infections caused by MRSA and MSSA strains. A wider study is needed to identify the effective components, the mode of action and the possible toxic effect in vivo of these ingredients.

  1. Eradication of Staphylococcus aureus Catheter-Related Biofilm Infections Using ML:8 and Citrox.

    Science.gov (United States)

    Hogan, S; Zapotoczna, M; Stevens, N T; Humphreys, H; O'Gara, J P; O'Neill, E

    2016-10-01

    Staphylococci are a leading cause of catheter-related infections (CRIs) due to biofilm formation. CRIs are typically managed by either device removal or systemic antibiotics, often in combination with catheter lock solutions (CLSs). CLSs provide high concentrations of the antimicrobial agent at the site of infection. However, the most effective CLSs against staphylococcal biofilm-associated infections have yet to be determined. The purpose of this study was to evaluate the efficacy and suitability of two newly described antimicrobial agents, ML:8 and Citrox, as CLSs against Staphylococcus aureus biofilms. ML:8 (1% [vol/vol]) and Citrox (1% [vol/vol]), containing caprylic acid and flavonoids, respectively, were used to treat S. aureus biofilms grown in vitro using newly described static and flow biofilm assays. Both agents reduced biofilm viability >97% after 24 h of treatment. Using a rat model of CRI, ML:8 was shown to inactivate early-stage S. aureus biofilms in vivo, while Citrox inactivated established, mature in vivo biofilms. Cytotoxicity and hemolytic activity of ML:8 and Citrox were equivalent to those of other commercially available CLSs. Neither ML:8 nor Citrox induced a cytokine response in human whole blood, and exposure of S. aureus to either agent for 90 days was not associated with any increase in resistance. Taken together, these data reveal the therapeutic potential of these agents for the treatment of S. aureus catheter-related biofilm infections. PMID:27458213

  2. Characterization of Toxin Genes and Antimicrobial Susceptibility of Staphylococcus aureus Isolates in Fishery Products in Iran

    Science.gov (United States)

    Arfatahery, Noushin; Davoodabadi, Abolfazl; Abedimohtasab, Taranehpeimaneh

    2016-01-01

    Staphylococcus aureus is one of the most common causes of seafood-borne diseases worldwide, which are attributable to the contamination of food by preformed enterotoxins. In this study, a total of 206 (34.3%) Staphylococcus aureus strains were obtained from 600 fish and shrimp samples and were tested for their antimicrobial susceptibility. We assessed the prevalence of the genes responsible for the staphylococcal enterotoxins (SEA, SEB) and toxic shock syndrome toxin 1 (TSST-1) genes. The results indicated that 34% of aqua food samples were contaminated with S. aureus, and 23.8% of these isolates were mec-A-positive. Sixty-four percent of the strains isolated from contaminated seafood was enterotoxigenic S. aureus, and 28.2% of SEs were MRSA-positive. The most prevalent genotype was characterized by the presence of the sea gene (45.2%), followed by the seb gene (18.5%), and the tst gene encoding TSST-1 was found in eight strains (3.9%). Of the 206 S. aureus isolates, 189 strains (84.9%) were resistant to at least one antibiotic. Given the frequent outbreaks of enterotoxigenic MRSA, it is necessary to make revisions to mandatory programmes to facilitate improved hygiene practices during fishing, aquaculture, processing, and sales to prevent the contamination of fishery products in Iran.

  3. Vancomycin and maltodextrin affect structure and activity of Staphylococcus aureus biofilms.

    Science.gov (United States)

    Kiamco, Mia Mae; Atci, Erhan; Khan, Qaiser Farid; Mohamed, Abdelrhman; Renslow, Ryan S; Abu-Lail, Nehal; Fransson, Boel A; Call, Douglas R; Beyenal, Haluk

    2015-12-01

    Hyperosmotic agents such as maltodextrin negatively impact bacterial growth through osmotic stress without contributing to drug resistance. We hypothesized that a combination of maltodextrin (osmotic agent) and vancomycin (antibiotic) would be more effective against Staphylococcus aureus biofilms than either alone. To test our hypothesis, S. aureus was grown in a flat plate flow cell reactor. Confocal laser scanning microscopy images were analyzed to quantify changes in biofilm structure. We used dissolved oxygen microelectrodes to quantify how vancomycin and maltodextrin affected the respiration rate and oxygen penetration into the biofilm. We found that treatment with vancomycin or maltodextrin altered biofilm structure. The effect on the structure was significant when they were used simultaneously to treat S. aureus biofilms. In addition, vancomycin treatment increased the oxygen respiration rate, while maltodextrin treatment caused an increase and then a decrease. An increased maltodextrin concentration decreased the diffusivity of the antibiotic. Overall, we conclude that (1) an increased maltodextrin concentration decreases vancomycin diffusion but increases the osmotic effect, leading to the optimum treatment condition, and (2) the combination of vancomycin and maltodextrin is more effective against S. aureus biofilms than either alone. Vancomycin and maltodextrin act together to increase the effectiveness of treatment against S. aureus biofilm growth.

  4. Frequency and Treatment of Methicillin Resistant Staphylococcus aureus in Obstetric and Gynaecological Sepsis

    International Nuclear Information System (INIS)

    Objective: To perform culture and sensitivity for pathogens causing puerperal and postoperative wound sepsis and determine the frequency of Methicillin Resistant Staphylococcus aureus (MRSA) in such infections. Study Design: Observational study. Place and Duration of Study: Obstetrics and Gynaecology Ward, Jinnah Postgraduate Medical Centre, Karachi, from December 2008 to May 2010. Methodology: All patients presenting with puerperal sepsis or postoperative wound infection were enrolled. Pus was collected for culture and sensitivity using standard technique. Two samples were taken from each patient; one before starting the treatment and one at the end of treatment. Ames transport medium was used. Empirical treatment with triple regimen (Ampicillin, Metronidazole and Gentamicin) was started immediately to cover Gram positive as well as negative bacteria in addition to anaerobic infection. After receiving the sensitivity report, antimicrobial agent were changed accordingly. Samples from ward and theater staff and environment were also taken to look for possible mode of transmission. Data was recorded on a proforma. Discrete variables are expressed as percentages. Results: Staphylococcus aureus was the most frequent organism isolated in 34.6% cases. Methicillin sensitive Staphylococcus aureus was seen in 20% cases and methicillin resistant Staphylococcus aureus was seen in 14.6%. Out of these 14.6% MRSA, (17) 77% was associated with puerperal sepsis and rest (5) 23% was associated with postoperative wound infection. It showed best sensitivity to vancomycin. Conclusion: Staphylococcus aureus and E. coli were common causative agent of postoperative infections and puerperal sepsis. (author)

  5. In vitro phagocytosis of methicillin resistant and methicillin sensitive staphylococcus aureus by human polymorphonuclear leucocytes

    International Nuclear Information System (INIS)

    Staphylococcus aureus is a gram positive bacterium that causes a number of diseases such as abscesses, infective endocarditis, septic arthritis, etc. It is acquiring resistance against many antibiotics like methicillin; therefore its control is becoming increasingly difficult. Peripheral blood phagocytes particularly polymorphonuclear leucocytes play an important role in the protective mechanisms against these organisms. Phagocytes interact with bacteria and phagocytose these microorganisms to kill them. Phenotypically different isolates of Staphylococcus aureus including methicillin resistant Staphylococcus aureus (MRSA) and methicillin sensitive Staphylococcus aureus (MSSA) were collected from various hospitals of Lahore, Pakistan. Fresh polymorphonuclaer leucocytes were obtained from healthy individuals by centrifugation using Ficol-Hypaque gradient combined with dextran sedimentation. Microbiological method was used for the determination of phagocytic index of phenotypic variants of Staphylococcus aureus. A significant difference was observed between the phagocytic index of both bacterial groups. MSSA group showed the Mean+-SD of 79.46%+-3.9 while MRSA group showed 72.35%+-2.5. Significant difference in phagocytic index indicates that it can be one of the mechanisms of MRSA to evade host immune system as compare to MSSA. (author)

  6. A study of phage- and ribotype patterns of Staphylococcus aureus isolated from bovine mastitis in the Nordic countries

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Wegener, Henrik Caspar; Jensen, N.E.;

    1997-01-01

    This study was conducted to investigate the geographical distribution of phage and ribotypes of Staphylococcus aureus causing bovine mastitis in the 5 Nordic countries. A total of 403 isolates of S. aureus was isolated from 403 different dairy herds. One hundred five strains were isolated in...... the isolates of ribotype 1 belonged to phage type 29/52. This combined type accounted for 17% of all the 403 isolates. These findings show that a large number of different types of S. aureus can be isolated from cases of bovine mastitis. However, few types predominate within different countries. These...... predominating types seem to be specific in each country, however, a single type was common for both Denmark, Sweden and Finland. This could suggest differences in the virulence or in modes of transmission of predominating and rare types of S. aureus associated with bovine mastitis....

  7. Invasion Success by Plant Breeding Evolutionary Changes as a Critical Factor for the Invasion of the Ornamental Plant Mahonia aquifolium

    CERN Document Server

    Ross, Christel Anne

    2009-01-01

    Invasive species are a major threat to global biodiversity and cause significant economic costs. Studying biological invasions is both essential for preventing future invasions and is also useful in order to understand basic ecological processes. Christel Ross investigates whether evolutionary changes by plant breeding are a relevant factor for the invasion success of Mahonia aquifolium in Germany. Her findings show that invasive populations differ from native populations in quantitative-genetic traits and molecular markers, whereas their genetic diversity is similar. She postulates that these evolutionary changes are rather a result of plant breeding, which includes interspecific hybridisation, than the result of a genetic bottleneck or the releases from specialist herbivores.

  8. Adaptive invasive species distribution models: A framework for modeling incipient invasions

    Science.gov (United States)

    Uden, Daniel R.; Allen, Craig R.; Angeler, David G.; Corral, Lucia; Fricke, Kent A.

    2015-01-01

    The utilization of species distribution model(s) (SDM) for approximating, explaining, and predicting changes in species’ geographic locations is increasingly promoted for proactive ecological management. Although frameworks for modeling non-invasive species distributions are relatively well developed, their counterparts for invasive species—which may not be at equilibrium within recipient environments and often exhibit rapid transformations—are lacking. Additionally, adaptive ecological management strategies address the causes and effects of biological invasions and other complex issues in social-ecological systems. We conducted a review of biological invasions, species distribution models, and adaptive practices in ecological management, and developed a framework for adaptive, niche-based, invasive species distribution model (iSDM) development and utilization. This iterative, 10-step framework promotes consistency and transparency in iSDM development, allows for changes in invasive drivers and filters, integrates mechanistic and correlative modeling techniques, balances the avoidance of type 1 and type 2 errors in predictions, encourages the linking of monitoring and management actions, and facilitates incremental improvements in models and management across space, time, and institutional boundaries. These improvements are useful for advancing coordinated invasive species modeling, management and monitoring from local scales to the regional, continental and global scales at which biological invasions occur and harm native ecosystems and economies, as well as for anticipating and responding to biological invasions under continuing global change.

  9. Evaluation of genetically inactivated alpha toxin for protection in multiple mouse models of Staphylococcus aureus infection.

    Directory of Open Access Journals (Sweden)

    Rebecca A Brady

    Full Text Available Staphylococcus aureus is a major human pathogen and a leading cause of nosocomial and community-acquired infections. Development of a vaccine against this pathogen is an important goal. While S. aureus protective antigens have been identified in the literature, the majority have only been tested in a single animal model of disease. We wished to evaluate the ability of one S. aureus vaccine antigen to protect in multiple mouse models, thus assessing whether protection in one model translates to protection in other models encompassing the full breadth of infections the pathogen can cause. We chose to focus on genetically inactivated alpha toxin mutant HlaH35L. We evaluated the protection afforded by this antigen in three models of infection using the same vaccine dose, regimen, route of immunization, adjuvant, and challenge strain. When mice were immunized with HlaH35L and challenged via a skin and soft tissue infection model, HlaH35L immunization led to a less severe infection and decreased S. aureus levels at the challenge site when compared to controls. Challenge of HlaH35L-immunized mice using a systemic infection model resulted in a limited, but statistically significant decrease in bacterial colonization as compared to that observed with control mice. In contrast, in a prosthetic implant model of chronic biofilm infection, there was no significant difference in bacterial levels when compared to controls. These results demonstrate that vaccines may confer protection against one form of S. aureus disease without conferring protection against other disease presentations and thus underscore a significant challenge in S. aureus vaccine development.

  10. Genotyping of Staphylococcus aureus in bovine mastitis and correlation to phenotypic characteristics.

    Science.gov (United States)

    Artursson, Karin; Söderlund, Robert; Liu, Lihong; Monecke, Stefan; Schelin, Jenny

    2016-09-25

    Reducing the prevalence of mastitis caused by Staphylococcus aureus (S. aureus) is essential to improve animal health and reduce economic losses for farmers. The clinical outcome of acute mastitis and risk of progression to persistent mastitis can, at least to some extent, be related to genetic variants of the strain causing the infection. In the present study we have used microarrays to investigate the presence of virulence genes in S. aureus isolates from dairy cows with acute clinical mastitis (n=70) and correlated the findings to other genotypic and phenotypic characteristics. Among the most commonly found virulence factors were genes encoding several hemolysin types, leukocidins D and lukM/lukF-P83, clumping factors A and B, fibrinogen binding protein and fibronectin-binding protein A. Some virulence factors e.g. fibronectin-binding protein B and Staphylococcus aureus surface protein G were less common. Genes coding for several staphylococcal enterotoxins and toxic shock syndrome toxin-1 (TSST-1) were commonly found, especially in one major pulsotype. No beta-lactamase genes were found in any common pulsotype, while present in some rare pulsotypes, indicated to be of human origin. Production of TSST-1, enterotoxins, hemolysins and beta-lactamase could all be positively correlated to presence of the corresponding genes. This study reveals a number of genotypic differences and similarities among common and rare pulsotypes of S. aureus from cases of mastitis in Sweden. The results could help the design of diagnostic tools to guide on-farm interventions according to the expected impact on udder health from a specific S. aureus genotype. PMID:27599942

  11. Genotyping of Staphylococcus aureus in bovine mastitis and correlation to phenotypic characteristics.

    Science.gov (United States)

    Artursson, Karin; Söderlund, Robert; Liu, Lihong; Monecke, Stefan; Schelin, Jenny

    2016-09-25

    Reducing the prevalence of mastitis caused by Staphylococcus aureus (S. aureus) is essential to improve animal health and reduce economic losses for farmers. The clinical outcome of acute mastitis and risk of progression to persistent mastitis can, at least to some extent, be related to genetic variants of the strain causing the infection. In the present study we have used microarrays to investigate the presence of virulence genes in S. aureus isolates from dairy cows with acute clinical mastitis (n=70) and correlated the findings to other genotypic and phenotypic characteristics. Among the most commonly found virulence factors were genes encoding several hemolysin types, leukocidins D and lukM/lukF-P83, clumping factors A and B, fibrinogen binding protein and fibronectin-binding protein A. Some virulence factors e.g. fibronectin-binding protein B and Staphylococcus aureus surface protein G were less common. Genes coding for several staphylococcal enterotoxins and toxic shock syndrome toxin-1 (TSST-1) were commonly found, especially in one major pulsotype. No beta-lactamase genes were found in any common pulsotype, while present in some rare pulsotypes, indicated to be of human origin. Production of TSST-1, enterotoxins, hemolysins and beta-lactamase could all be positively correlated to presence of the corresponding genes. This study reveals a number of genotypic differences and similarities among common and rare pulsotypes of S. aureus from cases of mastitis in Sweden. The results could help the design of diagnostic tools to guide on-farm interventions according to the expected impact on udder health from a specific S. aureus genotype.

  12. Alpha-Toxin Promotes Mucosal Biofilm Formation by Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Michele J Anderson

    2012-05-01

    Full Text Available Staphylococcus aureus causes numerous diseases in humans ranging from the mild skin infections to serious, life-threatening, superantigen-mediated Toxic Shock Syndrome (TSS. S. aureus may also be asymptomatically carried in the anterior nares, vagina or on the skin, which serve as reservoirs for infection. Pulsed-field gel electrophoresis clonal type USA200 is the most widely disseminated colonizer and a major cause of TSS. Our prior studies indicated that α-toxin was a major epithelial proinflammatory exotoxin produced by TSS S. aureus USA200 isolates. It also facilitated the penetration of TSS Toxin-1 (TSST-1 across vaginal mucosa. However, the majority of menstrual TSS isolates produce low α-toxin due to a nonsense point mutation at codon 113, designated hly, suggesting mucosal adaptation. The aim of this study was to characterize the differences between TSS USA200 strains [high (hla+ and low (hly+ α-toxin producers] in their abilities to infect and disrupt vaginal mucosal tissue. A mucosal model was developed using ex vivo porcine vaginal mucosa, LIVE/DEAD® staining and confocal microscropy to characterize biofilm formation and tissue viability of TSS USA 200 isolates CDC587 and MN8, which contain the α-toxin pseudogene (hly, MNPE (hla+ and MNPE isogenic hla knockout (hlaKO. All TSS strains grew to similar bacterial densities (1-5 x 108 CFU on the mucosa and were proinflammatory over 3 days. However, MNPE formed biofilms with significant reductions in the mucosal viability whereas neither CDC587, MN8 (hly+, or MNPE hlaKO, formed biofilms and were less cytotoxic. The addition of exogenous, purified α-toxin to MNPE hlaKO restored the biofilm phenotype. Our studies suggest α-toxin affects S. aureus phenotypic growth on vaginal mucosa, by promoting tissue disruption and biofilm formation; and α–toxin mutants (hly are not benign colonizers, but rather form a different type of infection, which we have termed high density pathogenic

  13. Baerere af Staphylococcus aureus som kilde til hospitalsinfektioner. Epidemiologiske og profylaktiske aspekter

    DEFF Research Database (Denmark)

    Kolmos, H J

    1999-01-01

    20% of the normal population are nasal carriers of Staphylococcus aureus (Sa), and the carrier rate is even higher in insulin dependent diabetics, intravenous drug addicts, patients on haemo- and peritoneal dialysis, and HIV infected patients. Nasal Sa carriers have an increased risk of Sa...... infections following invasive therapy. Mupirocin, a novel topical antibiotic, is highly effective against nasal Sa. A number of studies indicate that it may reduce the incidence of Sa infections in dialysis patients, however experience with other categories of patients is sparse. Surgical wound infection...

  14. Community-Associated Methicillin-Resistant Staphylococcus aureus in a Pediatric Emergency Department in Newfoundland and Labrador

    Directory of Open Access Journals (Sweden)

    Erin Peebles

    2014-01-01

    Full Text Available BACKGROUND: First-generation cephalosporins and antistaphylococcal penicillins are typically the first choice for treating skin and soft tissue infections (SSTI, but are not effective for infections caused by methicillin-resistant Staphylococcus aureus (MRSA. It is currently unclear what percentage of SSTIs is caused by community-associated MRSA in different regions in Canada.

  15. Staphylococcus aureus and Staphylococcal Food-Borne Disease: An Ongoing Challenge in Public Health

    OpenAIRE

    Jhalka Kadariya; Smith, Tara C.; Dipendra Thapaliya

    2014-01-01

    Staphylococcal food-borne disease (SFD) is one of the most common food-borne diseases worldwide resulting from the contamination of food by preformed S. aureus enterotoxins. It is one of the most common causes of reported food-borne diseases in the United States. Although several Staphylococcal enterotoxins (SEs) have been identified, SEA, a highly heat-stable SE, is the most common cause of SFD worldwide. Outbreak investigations have found that improper food handling practices in the retail ...

  16. Improved understanding of factors driving methicillin-resistant Staphylococcus aureus epidemic waves

    OpenAIRE

    Chatterjee SS; Otto M.

    2013-01-01

    Som S Chatterjee, Michael OttoPathogen Molecular Genetics Section, National Institute of Allergy and Infectious Diseases, Bethesda, MD, USAAbstract: Methicillin-resistant Staphylococcus aureus (MRSA) remains one of the most important causes of nosocomial infections worldwide. Since the global spread of MRSA in the 1960s, MRSA strains have evolved with increased pathogenic potential. Notably, some strains are now capable of causing persistent infections not only in hospitalized patients but al...

  17. Evaluation of four phenotypic methods for the rapid identification of methicillin resistant Staphylococcus aureus

    OpenAIRE

    Narasinga R. Bandaru; Srinivas Budati

    2016-01-01

    Background: Methicillin-resistant Staphylococcus aureus (MRSA), a superbug has been recognized as one of the major pathogens in hospitals as well as community settings. The prevalence of MRSA is 30 and ndash;70% and many studies have suggested an alarming rate of infections caused by this organism. In spite of modern diagnostic procedures and technological advancement, infections caused by MRSA still remain difficult to diagnose in developing countries like India. We tried to evaluate four ph...

  18. Antimicrobial (Drug) Resistance: Methicillin-Resistant Staphylococcus aureus (MRSA)

    Science.gov (United States)

    ... Marketing Share this: Main Content Area Methicillin-Resistant Staphylococcus aureus (MRSA) During the past four decades, methicillin-resistant Staphylococcus aureus , or MRSA, has evolved from a controllable ...

  19. Evolution of methicillin-resistant Staphylococcus aureus towards increasing resistance

    DEFF Research Database (Denmark)

    Strommenger, Birgit; Bartels, Mette Damkjær; Kurt, Kevin;

    2014-01-01

    To elucidate the evolutionary history of Staphylococcus aureus clonal complex (CC) 8, which encompasses several globally distributed epidemic lineages, including hospital-associated methicillin-resistant S. aureus (MRSA) and the highly prevalent community-associated MRSA clone USA300....

  20. Propionibacterium acnes biofilm - A sanctuary for Staphylococcus aureus?

    Science.gov (United States)

    Tyner, Harmony; Patel, Robin

    2016-08-01

    The purpose of this study was to measure the effect of combined culture of Propionibacterium acnes and Staphylococcus aureus on biofilm formation under different oxygen concentrations. We measured planktonic growth and biofilm formation of P. acnes and S. aureus alone and together under aerobic and anaerobic conditions. Both P. acnes and S. aureus grew under anaerobic conditions. When grown under anaerobic conditions, P. acnes with or without S. aureus formed a denser biomass biofilm than did S. aureus alone. Viable S. aureus was recovered from a16-day old combined P. acnes and S. aureus biofilm, but not a monomicrobial S. aureus biofilm.