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expression of antimicrobial peptides in diabetic foot ulcer.foot ulcers are one of the main diabetes complications due to its high frequency and difficulty of complete healing. there are several factors that participate in diabetic ulcers development and limited information exists about the role of antimicrobial peptides (amp) in its pathogenesis.201222047630
electrospun poly(l-lactic acid)-co-poly(ɛ-caprolactone) nanofibres containing silver nanoparticles for skin-tissue engineering.silver nanoparticles (agnps) and silver ions (ag(+)) show growth-inhibitory activity against microorganisms and have been used for decades as antibacterial agents in various fields. to fabricate a nanofibrous scaffold which is antibacterial against bacteria and non-toxic to cells, we electrospun composite poly(l-lactic acid)-co-poly(ɛ-caprolactone) nanofibres containing silver nanoparticles (pllcl-agnps) with different concentrations (0.25, 0.50 and 0.75 wt%) of silver nitrate (agno(3)) in pllcl ...201222244047
Thiadiazolidinones: A new class of alanine racemase inhibitors with antimicrobial activity against methicillin-resistant Staphylococcus aureus.Methicillin-resistant Staphylococcus aureus (MRSA) is a human pathogen and a major cause of hospital-acquired infections. New antibacterial agents that have not been compromised by bacterial resistance are needed to treat MRSA-related infections. We chose the S. aureus cell wall synthesis enzyme, alanine racemase (Alr) as the target for a high-throughput screening effort to obtain novel enzyme inhibitors, which inhibit bacterial growth. Among the 'hits' identified was a thiadiazolidinone with ch ...201222146584
comparison of the effects of human β-defensin 3, vancomycin, and clindamycin on staphylococcus aureus biofilm formation.despite improvements in surgical techniques and implant design in orthopedic surgery, implantation-associated infections are still a challenging problem for surgeons. in 2006, trace quantities of human β-defensin 3 (hbd-3) were found in human bone tissue and bone cells. human β-defensin 3 is a 45-amino-acid peptide that is considered the most promising class of defensin antimicrobial peptides and may help in the prevention and treatment of implantation-associated infections. studies of the effec ...201222229614
antibacterial peptides derived from caprine whey proteins, by digestion with human gastrointestinal juice.peptides in caprine whey were identified after in vitro digestion with human gastrointestinal enzymes in order to determine their antibacterial effect. the digestion was performed in two continuing steps using human gastric juice (ph 2·5) and human duodenal juice (ph 8) at 37°c. after digestion the hydrolysate was fractionated and 106 peptides were identified. from these results, twenty-two peptides, located in the protein molecules, were synthesised and antibacterial activity examined. strong a ...201121554806
the role of horizontal gene transfer in staphylococcus aureus host adaptation.staphylococcus aureus is an important human pathogen that also causes economically important infections of livestock. in a recent paper, we employed a population genomic approach to investigate the molecular basis of ruminant host adaptation by s. aureus. the data suggest that the common pathogenic clone associated with small ruminants originated in humans but has since adapted to its adopted host through a combination of allelic diversification, gene loss and acquisition of mobile genetic eleme ...201121555917
chimeric anti-staphylococcal enterotoxin b antibodies and lovastatin act synergistically to provide in vivo protection against lethal doses of seb.staphylococcal enterotoxin b (seb) is one of a family of toxins secreted by staphylococcus aureus that act as superantigens, activating a large fraction of the t-cell population and inducing production of high levels of inflammatory cytokines that can cause toxic shock syndrome (tss) and death. extracellular engagement of the tcr of t-cells and class ii mhc of antigen presenting cells by seb triggers the activation of many intracellular signaling processes. we engineered chimeric antibodies to b ...201122102880
staphylococcus aureus survival in human blood.methicillin-resistant staphylococcus aureus (mrsa) is abundant in hospitals and in the united states is a leading cause of mortality due to infectious agents. community-associated mrsa (ca-mrsa) strains such as usa300, which typically cause disease outside of healthcare settings, are also prevalent in the united states. although most ca-mrsa infections affect skin and soft tissue, the pathogen can enter the bloodstream and ultimately cause severe disease. in a recent paper, we used usa300-specif ...201121971187
Antibacterial potential of hGlyrichin encoded by a human gene.Emerging multidrug-resistant (MDR) bacteria are an enormous threat to human life because of their resistance to currently available antibiotics. The genes encoding antibacterial peptides have been studied extensively and are excellent candidates for a new generation of antibiotic drugs to fight MDR bacteria. In contrast to traditional antibiotics, antibacterial peptides, which do not cause drug resistance, have an unparalleled advantage. However, because most antibacterial peptides originate in ...201122083756
Novel anti-bacterial activities of ß-defensin 1 in human platelets: suppression of pathogen growth and signaling of neutrophil extracellular trap formation.Human ß-defensins (hBD) are antimicrobial peptides that curb microbial activity. Although hBD's are primarily expressed by epithelial cells, we show that human platelets express hBD-1 that has both predicted and novel antibacterial activities. We observed that activated platelets surround Staphylococcus aureus (S. aureus), forcing the pathogens into clusters that have a reduced growth rate compared to S. aureus alone. Given the microbicidal activity of ß-defensins, we determined whether hBD fami ...201122102811
immunopathogenesis of staphylococcus aureus pulmonary infection.staphylococcus aureus is a common human pathogen highly evolved as both a component of the commensal flora and as a major cause of invasive infection. severe respiratory infection due to staphylococci has been increasing due to the prevalence of more virulent usa300 ca-mrsa strains in the general population. the ability of s. aureus to adapt to the milieu of the respiratory tract has facilitated its emergence as a respiratory pathogen. its metabolic versatility, the ability to scavenge iron, coo ...201122037948
hle-inhibitory alkaloids with a polyketide skeleton from the marine-derived fungus coniothyrium cereale.the marine endophytic fungus coniothyrium cereale produces the structurally unusual polyketide-type alkaloids (-)-cereolactam (1) and (-)-cereoaldomine (3), incorporating a lactam and an imine functionality, respectively, as well as the related metabolite (-)-trypethelone (2). compounds 1 and 3 showed selective inhibition of human leukocyte elastase with ic50 values of 9.28 and 3.01 μm, respectively. compound 2 was found to be inhibitory toward mycobacterium phlei, staphylococcus aureus, and esc ...201121923104
a usa300 variant and other human-related methicillin-resistant staphylococcus aureus strains infecting cats and dogs in france.to characterize methicillin-resistant staphylococcus aureus (mrsa) clinical strains from cats and dogs in france, and to compare the clones identified with the distribution of french human mrsa.201122146878
phagocytosis and intracellular killing of heterogeneous vancomycin-intermediate staphylococcus aureus strains.risk factors for invasive infections by heterogeneous vancomycin-intermediate staphylococcus aureus (hvisa) may involve resistance to opsonophagocytosis and bacterial killing. hvisa strains typically have a thickened cell wall with altered peptidoglycan cross-linking. to determine whether hvisa may be endowed with an increased resistance to phagocytosis, this study assessed the characteristics of uptake and killing by granulocytes of three hvisa strains. all isolates were analysed by multilocus ...201121959204
Detection of Methicillin-Resistant Staphylococcus aureus (MRSA) in Backyard Pigs and Their Owners, Michigan, USA.Methicillin-resistant Staphylococcus aureus (MRSA) have been reported in commercially raised pigs and their human handlers, raising concerns of zoonotic transmission. To determine whether MRSA in backyard-raised pigs is commonly transmitted to their human owners, a matched study of this type of pigs and their owners was conducted in selected counties in Michigan. Nasal swabs from matched owner-pig pairs (n = 50 pairs) with a few unmatched pig (n = 3) and human (n = 4) samples were collected and ...201121914153
the staphylococcus aureus peptidoglycan protects mice against the pathogen and eradicates experimentally induced infection.staphylococcus aureus, in spite of antibiotics, is still a major human pathogen causing a wide range of infections. the present study describes the new vaccine a170pg, a peptidoglycan-based vaccine. in a mouse model of infection, a170pg protects mice against a lethal dose of s. aureus. protection lasts at least 40 weeks and correlates with increased survival and reduced colonization. protection extends into drug-resistant (mrsa or visa) and genetically diverse clinical strains. the vaccine is ef ...201122145040
evaluation of lhp-« (1% hydrogen peroxide) cream versus petrolatum and untreated controls in open wounds in healthy horses: a randomized, blinded control study.abstract:201121718487
induction of contact-dependent cd8(+) regulatory t cells through stimulation with staphylococcal and streptococcal superantigens(1).the bacterial superantigen exotoxins of staphylococcus aureus and streptococcus pyogenes are potent stimulators of polyclonal t cell proliferation. they are the causes of toxic shock syndrome but also induce cd25(+) foxp3(+) regulatory cells in the cd4 compartment. several studies have recently described different forms of antigen-induced regulatory cd8(+) t cells in the context of inflammatory diseases and chronic viral infections. in this paper we show that bacterial superantigens are potent ...201122043981
antimicrobial evaluation of huilliche plant medicine used to treat wounds.the traditional use of 40 plant species used for treatment of wounds and associated infections by the huilliche people of chile was evaluated against bacterial and fungal human pathogens, especially including wound pathogens.201121939748
molecular characterization and antimicrobial susceptibility of nasal staphylococcus aureus isolates from a chinese medical college campus.staphylococcus aureus colonization and infection occur more commonly among persons living or working in crowded conditions, but characterization of s. aureus colonization within medical communities in china is lacking. a total of 144 (15.4%, 144/935) s. aureus isolates, including 28 (3.0%, 28/935) mrsa isolates, were recovered from the nares of 935 healthy human volunteers residing on a chinese medical college campus. all s. aureus isolates were susceptible to vancomycin, quinupristin/dalfoprist ...201122114670
Antibacterial and antifungal activities from leaf extracts of Cassia fistula l.: An ethnomedicinal plant.This study was carried out with an objective to investigate the antibacterial and antifungal potentials of leaves of Cassia fistula Linn. The aim of the study is to assess the antimicrobial activity and to determine the zone of inhibition of extracts on some bacterial and fungal strains. In the present study, the microbial activity of hydroalcohol extracts of leaves of Cassia fistula Linn. (an ethnomedicinal plant) was evaluated for potential antimicrobial activity against medically important ba ...201122171301
cheminformatics-driven discovery of selective, nanomolar inhibitors for staphylococcal pyruvate kinase.we have recently mapped the protein interaction network of methicillin-resistant staphylococcus aureus (mrsa), which revealed its scale-free organization with characteristic presence of highly connected hub proteins that are critical for bacterial survival. here we report the discovery of inhibitors that are highly potent against one such hub target, staphylococcal pyruvate kinase (pk). importantly, the developed compounds demonstrate complete selectivity for the bacterial enzyme compared to all ...201122066782
cluster-forming property correlated with hemolytic activity by staphylococcal γ-hemolysin transmembrane pores.staphylococcal γ-hemolysin (hlg) is a pore-forming toxin consisting of two separate components, lukf (34kda) and hlg2 (32kda). here we show that hlg pores aggregate and form clusters on human erythrocyte membranes in association with increasing hemolytic activity. quantitative analysis using transmission electron microscopy and image processing revealed that the formation of single pores and clusters is related to the release of potassium ions and of hemoglobin from erythrocytes, respectively. t ...201122001207
the first detection of methicillin-resistant staphylococcus aureus st398 in pigs in korea.in order to determine the presence of methicillin-resistant staphylococcus aureus (mrsa) in pigs in korea, a total of 657 nasal swabs were collected from pigs on 66 different pig farms nationwide during february 2008-may 2009. the prevalences of mrsa positive samples in pigs and farms were 3.2% (21/657) and 22.7% (15/66), respectively. two different types were found among the 21 mrsa isolates: 17 strains of livestock-associated type (la; st398 or st541/spa t034) and 4 strains of human-associated ...201121899962
a new target for staphylococcus aureus associated with keratitis.staphylococcus aureus is a leading cause of keratitis, with an increased number of isolates exhibiting antibiotic resistance. therefore, we need to understand the present situation regarding drug-resistant s. aureus in the ocular site. it has been shown that 35% of s. aureus isolates from ocular sites are methicillin-resistant staphylococcus aureus (mrsa). mrsa isolates from ocular sites have a high rate of multiple mutations and high levels of resistance against fluoroquinolones. wall teichoic ...201121912228
rhesus macaques (macaca mulatta) are natural hosts of specific staphylococcus aureus lineages.currently, there is no animal model known that mimics natural nasal colonization by staphylococcus aureus in humans. we investigated whether rhesus macaques are natural nasal carriers of s. aureus. nasal swabs were taken from 731 macaques. s. aureus isolates were typed by pulsed-field gel electrophoresis (pfge), spa repeat sequencing and multi-locus sequence typing (mlst), and compared with human strains. furthermore, the isolates were characterized by several pcrs. thirty-nine percent of 731 ma ...201122028827
colonization, pathogenicity, host susceptibility, and therapeutics for staphylococcus aureus: what is the clinical relevance?staphylococcus aureus is a human commensal that can also cause a broad spectrum of clinical disease. factors associated with clinical disease are myriad and dynamic and include pathogen virulence, antimicrobial resistance, and host susceptibility. additionally, infection control measures aimed at the environmental niches of s. aureus and therapeutic advances continue to impact upon the incidence and outcomes of staphylococcal infections. this review article focuses on the clinical relevance of a ...201122160374
3-cyano-8-methyl-2-oxo-1,4-disubstituted-1,2,5,6,7,8-hexahydroquinolines. synthesis and biological evaluation as antimicrobial and cytotoxic agents.the synthesis, in vitro antimicrobial and cytotoxic activities of some novel hexahydroquinolines supported with various pharmacophores are described. the results revealed that 18 compounds displayed pronounced activity against staphylococcus aureus and escherichia coli bacteria beside a moderate antifungal activity. compound 25 is the most active candidate with equipotency to ampicillin against s. aureus, e. coli and pseudomonas aeruginosa, together with an obvious antifungal activity. additiona ...201122136527
magnetic drug targeting as new therapeutic option for the treatment of biomaterial infections.implant-associated infections are a challenging problem in surgery. bacteria in biofilms are difficult to treat as they are less susceptible to antibiotics or antiseptics which require high drug concentrations at the site of infection. we present a novel strategy to concentrate high antibiotic doses systemically at the target site using newly developed antibiotic-functionalized nanoparticles directed by a magnetic drug-targeting system. the important and effective antibiotic gentamicin served as ...201122182398
Antimicrobial Proteins from Snake Venoms: Direct Bacterial Damage and Activation of Innate Immunity Against Staphylococcus aureus Skin Infection.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) re ...201122050758
Anti-tuberculosis drugs and human polymorphonuclear leukocyte functions.The polymorphonuclear leukocyte (PMN) is considered to be of importance in the early stages of human tuberculosis (TB). We examined the four drugs (rifampicin, isoniazid, pyrazinamide and ethambutol) commonly used in the DOTS (directly observed treatment, short-course) strategy against TB for their effects on the functions of the human PMN, separately and combined.201121912116
gut cavp is an innate immune protein against bacterial challenge in amphioxus branchiostoma belcheri.the importance of calcium-binding proteins in immune response of vertebrates is determined, but whether they have the role in invertebrates is largely unknown. in the present study, phylogenetic analysis indicated that calcium vector protein (cavp), a protein unique to amphioxus, shared 68% similarity in amino acid sequence with human and mouse calmodulin (cam). cavp cdna was cloned into a bacterial vector pet-32a, and its his-tagged fusion protein was produced in eschherichia coli cells (bl21). ...201121624472
biofilm formation on silicone tympanostomy tubes with polyvinylpyrrolidone coating.to determine whether biofilm formation on silicone tympanostomy tubes (tts) is prevented by polyvinylpyrrolidone (pvp) coating.201121242541
[71-year old patient with sepsis, pericardial effusion and pulmonary infiltrates.]a 71-year old man with sepsis, hemorrhagic pericardial effusion and pulmonary embolism was admitted on the intensive care unit. in blood cultures and in pericardial effusion, staphylococcus aureus was isolated. transeosophageal echocardiography showed a massive pulmonary valve endocarditis. right-sided endocarditis is a rare variant of endocarditis and may occur in consequence of contaminated drug solutions or infected intravenous catheter. the prognosis is relatively good, worse prognosis show ...201121253681
human leukocyte antigen class ii transgenic mouse model unmasks the significant extrahepatic pathology in toxic shock syndrome.among the exotoxins produced by staphylococcus aureus and streptococcus pyogenes, the superantigens (sags) are the most potent t-cell activators known to date. sags are implicated in several serious diseases including toxic shock syndrome (tss), kawasaki disease, and sepsis. however, the immunopathogenesis of tss and other diseases involving sags are still not completely understood. the commonly used conventional laboratory mouse strains do not respond robustly to sags in vivo. therefore, they m ...201121641398
radiosynthesis and biological evaluation of the (99m)tc-tricarbonyl moxifloxacin dithiocarbamate complex as a potential staphylococcus aureus infection radiotracer.in the present investigation, radiosynthesis of the (99m)tc-tricarbonyl moxifloxacin dithiocarbamate complex ((99m)tc(co)(3)-mxnd) and its biological evaluation in male wister rats (mwr) artificially infected with staphylococcus aureus (s. aureus) was assessed. the (99m)tc(co)(3)-mxnd complex was radiochemically examined in terms of stability in saline and in serum and biologically its in-vitro binding with s. aureus and percent absorption in mwr models. radiochemically the (99m)tc(co)(3)-mxnd c ...201121256038
high prevalence of edin-c encoding rhoa-targeting toxin in clinical isolates of staphylococcus aureus.staphylococcus aureus, a major causative agent of human infection, produces a large array of virulence factors, including various toxins. among them, the host rhoa gtpase adp-ribosylating edin toxins are considered as potential virulence factors. using the polymerase chain reaction (pcr) assay, we analyzed the virulence profile of 256 s. aureus isolates from various clinical sites of infections. we developed specific primers to detect the three isoforms of edin-encoding genes. we found a prevale ...201121311940
bacterial virulence in the moonlight: multitasking bacterial moonlighting proteins are virulence determinants in infectious disease.men may not be able to multi-task, but it is emerging that proteins can. this capacity of proteins to exhibit more than one function is termed protein moonlighting and, surprisingly, many highly conserved proteins involved in metabolic regulation or the cell stress response have a range of additional biological actions which are involved in bacterial virulence. this review highlights the multiple roles exhibited by a range of bacterial proteins, such as glycolytic and other metabolic enzymes and ...201121646455
chemical synthesis of bacterial lipoteichoic acids: an insight on its biological significance.during infections caused by gram-negative bacteria, lipopolysaccharide (lps, endotoxin) has a dominant role leading to fulminant pro-inflammatory reactions in the host. as there is no lps in gram-positive bacteria, other microbial cell wall components have been identified to be the causative agent for the pro-inflammatory activity since also gram-positive bacterial infections lead to comparable clinical symptoms and reactions. on search for the "gram-positive endotoxin" a widely accepted hypothe ...201121327200
influence of the recombinant human 70-kda heat-shock protein on simulation of gram-positive sepsis in rats. 201121562946
nsars is a cell-envelope-stress sensing two-component system of staphylococcus aureus.s. aureus possesses 16 two-component systems (tcs), two of which (grars & nsars) belong to the intramembrane-sensing histidine kinase (im-hk) family, conserved within the firmicutes. nsars has recently been documented as being important for nisin-resistance in s. aureus. in this study we present a characterization of nsars and reveal that, as with other im-hk tcs, it responds to disruptions in the cell-envelope. analysis using a lacz reporter-gene fusion demonstrated that nsars expression is upr ...201121565927
the saer/s gene regulatory system induces a pro-inflammatory cytokine response during staphylococcus aureus infection.community-associated methicillin-resistant staphylococcus aureus accounts for a large portion of the increased staphylococcal disease incidence and can cause illness ranging from mild skin infections to rapidly fatal sepsis syndromes. currently, we have limited understanding of s. aureus-derived mechanisms contributing to bacterial pathogenesis and host inflammation during staphylococcal disease. herein, we characterize an influential role for the saer/s two-component gene regulatory system in m ...201121603642
targeting the host-pathogen interface for treatment of staphylococcus aureus infection.recent emergence of methicillin-resistant staphylococcus aureus both within and outside healthcare settings has accelerated the use of once reserved last line antibiotics such as vancomycin. with increased use of antibiotics, there has been a rapid rise in the rate of resistance development to the anti-mrsa drugs. as the antibiotic pipeline becomes strained, alternative strategies are being sought for future treatment of s. aureus. here, we review several novel anti-staphylococcal strategies tha ...201122089960
initial efforts toward the optimization of arylomycins for antibiotic activity.while most clinically used antibiotics were derived from natural products, the isolation of new broad-spectrum natural products has become increasingly rare and narrow-spectrum agents are typically deemed unsuitable for development due to intrinsic limitations of their scaffold or target. however, it is possible that the spectrum of a natural product antibiotic might be limited by specific resistance mechanisms in some bacteria, such as target mutations, and the spectra of such "latent" antibiot ...201121630667
peptidylarginine deiminases present in the airways during tobacco smoking and inflammation can citrullinate the host defense peptide ll-37 resulting in altered activities.bacterial colonization of the lower respiratory tract is frequently seen in copd and may cause exacerbations leading to deterioration of the disease. an important part of the innate lung immunity is antimicrobial peptides, not least the cathelicidin hcap-18/ll-37. peptidylarginine deiminases (padi) posttranslationally modifies proteins by converting cationic peptidylarginine residues to neutral peptidylcitrulline. increased presence of padi2 and citrullinated proteins has been demonstrated in th ...201121960546
fibronigen is a ligand for the s. aureus mscramm bbp (bone sialoprotein-binding protein).mscramms (microbial surface components recognizing adhesive matrix molecules) are bacterial surface proteins mediating adherence of the microbes to components of the extracellular matrix of the host. on staphylococci the mscramms often have multiple ligands. consequently we hypothesized that the s. aureus mscramm bbp (bone sialoprotein-binding protein) might recognize host molecules other than the identified bone protein. a ligand screen revealed that bbp binds human fibrinogen (fg) but not fg f ...201121642438
two antimicrobial and nematicidal peptides derived from sequences encoded picea sitchensis.two antimicrobial peptides (piceain 1 and 2) derived from sequences encoded picea sitchensis are identified. their amino acid sequences are kslrprcwikikfrckslkf and rprcwikikfrckslkf, respectively. one intra-molecular disulfide bridge is formed by these two half-cysteines in both piceain 1 and 2. antimicrobial activities of synthesized piceains against several kinds of microorganisms were tested. they showed antimicrobial activities against escherichia coli, pseudomonas aeruginosa, staphylococcu ...201121644248
antimicrobial fibers: therapeutic possibilities and recent advances.the emergence of multi-drug-resistant bacteria such as methicillin-resistant strains of staphylococcus aureus (mrsa), vancomycin-resistant enterococci, pseudomonas aeruginosa, acinetobacter baumannii and extended-spectrum β-lactamase (carbapenemase)-producing enterobacteriaceae is becoming a serious threat. new-generation antimicrobial agents need to be developed. this includes the design of novel antimicrobial compounds and drug-delivery systems. this review provides an introduction into differ ...201122004087
auxotrophic mutant of staphylococcus aureus interferes with nasal colonization by the wild type.staphylococcus aureus nasal carriage is a risk factor for infection in humans, particularly in the hospital setting. bacterial interference was used as an alternative strategy for the prevention of upper respiratory, urogenital and gastrointestinal tract infections. this study was designed to assess if the administration of a live-attenuated aroa mutant of s. aureus is useful as a potential approach to prevent transient staphylococcal nasal carriage by virulent strains. we constructed an aroa mu ...201121784166
structural and in vitro cytotoxicity studies on 1h-benzimidazol-2-ylmethyl-n-phenyl amine and its pd(ii) and pt(ii) complexes.[mlcl(2)]·zh(2)o (l=(1h-benzimidazol-2-ylmethyl)-n-phenyl amine; m=pd, z=0; m=pt, z=1) and [pdl(oh(2))(2)]·2x·zh(2)o (x=br, i, no(3), z=0; x=scn, z=1) complexes were synthesized as potential anticancer compounds and characterized by elemental analysis, spectral and thermal methods. ft-ir and (1)h nmr studies revealed that the benzimidazole l is coordinated to the metal ions via the pyridine-type nitrogen (n(py)) of the benzimidazole ring and secondary amino group (nh(sec)). quantum mechanical ca ...201121763187
bacitracin and nisin resistance in staphylococcus aureus: a novel pathway involving the bras/brar two-component system (sa2417/sa2418) and both the brad/brae and vrad/vrae abc transporters.two-component systems (tcss) are key regulatory pathways allowing bacteria to adapt their genetic expression to environmental changes. bacitracin, a cyclic dodecylpeptide antibiotic, binds to undecaprenyl pyrophosphate, the lipid carrier for cell wall precursors, effectively inhibiting peptidoglycan biosynthesis. we have identified a novel and previously uncharacterized tcs in the major human pathogen staphylococcus aureus that we show to be essential for bacitracin and nisin resistance: the bra ...201121696458
molecular insights into the control of transcription initiation at the staphylococcus aureus agr operon.the accessory gene regulatory (agr) operon of the opportunistic human pathogen staphylococcus aureus is a prime pathogenesis factor in this bacterium. the agr operon consists of two transcription units, rnaii and rnaiii, which are transcribed from divergent promoters, p2 and p3, respectively. rnaii encodes a quorum-sensing system, including agra, the master transcription activator of the agr operon. rnaiii is the effector rna molecule that regulates the expression of many virulence genes. owing ...201121741390
the sbi protein is a multifunctional immune evasion factor of staphylococcus aureus.the second immunoglobulin-binding protein (sbi) of staphylococcus aureus has two n-terminal domains that bind the fc region of igg in a fashion similar to that of protein a and two domains that can bind to the complement protein c3 and promote its futile consumption in the fluid phase. it has been proposed that sbi helps bacteria to avoid innate immune defenses. by comparing a mutant defective in sbi with mutants defective in protein a, clumping factor a, iron-regulated surface determinant h, an ...201121708997
bactericidal activity and in vitro cytotoxicity assessment of hydroxyapatite containing gold nanoparticles.hydroxyapatite (ha) containing gold (au) nanoparticles was synthesized for the biomedical applications. the morphology, structure and thermal properties of the ha containing au nanoparticles were characterized by field emission scanning electron microscopy (fe-sem), transmission electron microscopy (tem), energy dispersive x-ray (edx) spectroscopy, x-ray diffraction (xrd), fouriertransform infrared spectroscopy (ft-ir) and thermogravimetry (tga). xrd patterns clearly revealed the formation of ha ...201121830474
staphylococcal ╬▒-toxin induces a higher t cell proliferation and interleukin-31 in atopic dermatitis.background: patients with atopic dermatitis (ad) are frequently colonized with ╬▒-toxin-producing staphylococcus aureus which is in turn positively correlated with the severity of eczema. methods: in this study we addressed t cell proliferation and t cell as well as monocyte cytokine secretion upon ╬▒-toxin stimulation in peripheral blood mononuclear cells (pbmcs) from ad patients compared to healthy controls. results: we found that ╬▒-toxin stimulation of pbmcs markedly enhanced t cell prolifer ...201121832830
methicillin resistant s. aureus in human and bovine mastitis.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 ca ...201121984431
synthesis, antimicrobial and antiproliferative activity of novel silver(i) tris(pyrazolyl)methanesulfonate and 1,3,5-triaza-7-phosphadamantane complexes.five new silver(i) complexes of formulas [ag(tpms)] (1), [ag(tpms)(pph(3))] (2), [ag(tpms)(pcy(3))] (3), [ag(pta)][bf(4)] (4), and [ag(tpms)(pta)] (5) {tpms = tris(pyrazol-1-yl)methanesulfonate, pph(3) = triphenylphosphane, pcy(3) = tricyclohexylphosphane, pta = 1,3,5-triaza-7-phosphaadamantane} have been synthesized and fully characterized by elemental analyses, (1)h, (13)c, and (31)p nmr, electrospray ionization mass spectrometry (esi-ms), and ir spectroscopic techniques. the single crystal x- ...201121999582
expression of matrix metalloproteinase-9 and -12 in porcine lung infections.matrix metalloproteinases (mmps) play a variety of roles during organogenesis, in the immune response and during acute and chronic diseases as well as in tissue remodelling. during the last decade, the pig has become used increasingly as a model for human diseases; however, studies on the expression of porcine mmps are limited. in the present study species-specific antibodies were produced to investigate the expression of mmp-9 and mmp-12 immunohistochemically in lungs from pigs infected with ac ...201121737093
comparative ethnobotany and in-the-field antibacterial testing of medicinal plants used by the bulu and inland kaulong of papua new guinea.ethnopharmacological relevance: the island of new britain in papua new guinea is an area of great floristic and cultural diversity that has received little attention from ethnobotanists. here we present the results of a comparative medicinal ethnobotanical survey of the bulu and inland kaulong; two distinct people groups inhabiting lowland rainforest on different sides of the island. a high proportion of species are used in the treatment of bacterial infections and plants with antibacterial acti ...201122154578
congenital alterations of nemo glutamic acid 223 result in hypohidrotic ectodermal dysplasia and immunodeficiency with normal serum igg levels.hypomorphic mutations in the nuclear factor-+¦b (nf-+¦b) essential modulator (nemo) gene result in a variable syndrome of somatic and immunologic abnormalities. clinically relevant genotype-phenotype associations are essential to understanding this complex disease.201121704885
the flexible loop of staphylococcus aureus isdg is required for its degradation in the absence of heme.degradation of specific native proteins allows bacteria to rapidly adapt to changing environments when the activity of those proteins is no longer required. although these processes are vital to bacterial survival, relatively little is known regarding how bacterial proteins are recognized and targeted for degradation. staphylococcus aureus is an important human pathogen that requires iron for growth and pathogenesis. in the vertebrate host, s. aureus fulfills its iron requirement by obtaining he ...201121728357
staphylococcus aureus biofilm and planktonic cultures differentially impact gene expression, mapk phosphorylation, and cytokine production in human keratinocytes.abstract:201121693040
infectious disease.athletes are susceptible to the same infections as the general population. however, special considerations often need to be taken into account when dealing with an athlete who has contracted an infectious disease. health care providers need to consider how even common illnesses can affect an athlete's performance, the communicability of the illness to team members, and precautions/contraindications related to athletic participation. recent advances in the prevention, diagnosis, and/or management ...201121658549
Fulminant Candidemia Diagnosed by Prompt Detection of Pseudohyphae in a Peripheral Blood Smear.A 77-year-old man treated with prednisolone for pemphigus developed severe sepsis by Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus. Several antibiotics were administered. A peripheral blood smear showed growth of a large number of yeast extending pseudohyphae which could be seen both inside and outside of leucocytes. Antifungal agents were added immediately; however, he did not recover. Several days later, blood culture showed Candida albicans septicemia. The autopsy rev ...201122173051
porphyromonas gingivalis enzymes enhance infection with human metapneumovirus in vitro.relatively recently discovered, the human metapneumovirus (hmpv) is a human pathogen with worldwide prevalence, accounting for a substantial percentage of respiratory tract diseases. concurrent viral and bacterial infections enable intricate mechanisms of cooperation between pathogens, which complicate the symptoms and outcome of the disease. such bilateral interactions are based on the modulation of bacterial growth on epithelium pathologically altered during viral illness and the modulation of ...201121715599
Expansion of T helper type 17 lymphocytes in patients with chronic granulomatous disease.Hyper-immunoglobulin (Ig)E syndrome (HIES) is a primary immunodeficiency associated with mutations in STAT3 resulting in impaired development of T helper type 17 (Th17) lymphocytes. HIES patients with a reduced frequency of Th17 cells present with infections caused by Staphylococcus aureus and/or Candida strains. The same spectrum of pathogens is present in patients with chronic granulomatous disease (CGD).We analysed the characteristics of the Th17 compartment in HIES and CGD. HIES patients sho ...201121910722
effect of low-concentration chlorine dioxide gas against bacteria and viruses on a glass surface in wet environments.to evaluate the efficacy of low-concentration chlorine dioxide (clo(2)) gas against model microbes in the wet state on a glass surface.201121950421
structural basis for hemoglobin capture by staphylococcus aureus cell-surface protein, isdh.pathogens must steal iron from their hosts to establish infection. in mammals, hemoglobin (hb) represents the largest reservoir of iron, and pathogens express hb-binding proteins to access this source. here, we show how one of the commonest and most significant human pathogens, staphylococcus aureus, captures hb as the first step of an iron-scavenging pathway. the x-ray crystal structure of hb bound to a domain from the isd (iron-regulated surface determinant) protein, isdh, is the first structu ...201121917915
Streptococcus pneumoniae exposure is associated with human metapneumovirus seroconversion and increased susceptibility to in vitro HMPV infection.It remains largely unknown which factors determine the clinical outcome of human metapneumovirus (HMPV) infections. The aim of the present study was to analyse whether exposure to bacterial pathogens can influence HMPV infections. From 57 children, serum samples and colonization data for Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus and Streptococcus pneumoniae were collected at 1.5, 6, 14 and 24 months of age. Seroconversion rates to HMPV were determined and related to ba ...201121883660
dna, protein binding, cytotoxicity, cellular uptake and antibacterial activities of new palladium(ii) complexes of thiosemicarbazone ligands: effects of substitution on biological activity.the coordination propensities of 4(n,n')-diethylaminosalicylaldehyde-4(n)-substituted thiosemicarbazones (h(2)l(1-4)) were investigated by reacting with an equimolar amount of [pdcl(2)(pph(3))(2)]. the new complexes were characterized by various spectroscopic techniques. the structure determination of the complexes [pd(deasal-tsc)(pph(3))] (1), [pd(deasal-mtsc)(pph(3))] (2) and [pd(deasal-etsc)(pph(3))] (3) by x-ray crystallography showed that ligands are coordinated in a dibasic tridentate ons ...201122051854
loop-mediated isothermal amplification assay for the diagnosis of retinitis caused by herpes simplex virus-1.a loop-mediated isothermal amplification (lamp) assay was developed for the detection of herpes simplex virus 1 (hsv-1). the specificity of the assay was tested using dna extracted from hsv-1-infected rabbit corneal epithelium cultures, hsv-2 grown on vero cell line, cytomegalovirus (cmv) (ad-169), varicella zoster virus (vzv) (oka-vaccine), adenovirus, aspergillus flavus and staphylococcus aureus. the specificity of lamp was confirmed by bidirectional sequencing of the amplicons. the sensitivit ...201120298270
infected abdominal aortic aneurysm due to morganella morganii: ct findings.an infected aortic aneurysm, or mycotic aneurysm, is a rare arterial dilatation due to destruction of the infected vessel wall. common pathogens resulting in an infected aortic aneurysm are salmonella and clostridium species, as well as staphylococcus aureus; morganella morganii, on the other hand, is very rare. an infected abdominal aortic aneurysm has tendencies to grow rapidly and to rupture. the mortality rate is high in patients undergoing emergent surgical intervention. we report the case ...201120352211
fusobacterium nucleatum regulation of neutrophil transcription.abnormal neutrophil responses have been observed in periodontitis patients, including hyper-reactivity in terms of production of reactive oxygen species (ros) following exposure to the key quorum-sensing plaque bacterium, fusobacterium nucleatum. this study was designed to characterize the transcriptional response of neutrophils to f. nucleatum.201120663022
immune evasion cluster-positive bacteriophages are highly prevalent among human staphylococcus aureus strains, but they are not essential in the first stages of nasal colonization.the staphylococcus aureus immune evasion cluster (iec), located on β-haemolysin-converting bacteriophages (βc-φs), encodes the immune-modulating proteins chemotaxis inhibitory protein, staphylococcal complement inhibitor (scin), staphylococcal enterotoxin a and staphylokinase. its precise role in s. aureus colonization is unclear. we studied the presence of the iec-carrying bacteriophages in human and animal s. aureus isolates, using pcr for the gene encoding scin (scn). human isolates were obta ...201120370801
ciprofloxacin-modified electrosynthesized hydrogel coatings to prevent titanium-implant-associated infections.new promising and versatile materials for the development of in situ sustained release systems consisting of thin films of either poly(2-hydroxyethyl methacrylate) or a copolymer based on poly(ethylene-glycol diacrylate) and acrylic acid were investigated. these polymers were electrosynthesized directly on titanium substrates and loaded with ciprofloxacin (cip) either during or after the synthesis step. x-ray photoelectron spectroscopy was used to check the cip entrapment efficiency as well as i ...201120659594
mannose-binding lectin (mbl2) and ficolin-2 (fcn2) polymorphisms in patients on peritoneal dialysis with staphylococcal peritonitis.mannose-binding lectin (mbl) and ficolin-2 (fcn) are activators of the lectin pathway of complement and act as primary defences against infection. single-nucleotide polymorphisms (snps) in the mbl2 and fcn2 genes influence the functionality of the proteins. both proteins are capable of binding staphylococci, which are pathogens that frequently cause peritonitis in patients on continuous ambulatory peritoneal dialysis (capd). we studied the role of polymorphisms in the mbl2 and fcn2 genes as a ri ...201120682603
evidence of multiple virulence subtypes in nosocomial and community-associated mrsa genotypes in companion animals from the upper midwestern and northeastern united states.not much is known about the zoonotic transmission of methicillin-resistant staphylococcus aureus (mrsa) in companion animals in the united states. we report the rate of prevalence of s. aureus and mrsa recovered from clinical samples of animals requiring treatment at veterinary clinics throughout the upper midwestern and northeastern united states.201120739580
methyl-β-cyclodextrin modified vascular prosthesis: influence of the modification level on the drug delivery properties in different media.a textile polyester vascular graft was modified with methyl-β-cyclodextrin (meβcd) to obtain a new implant capable of releasing antibiotics directly in situ at the site of operation over a prolonged period and thereby prevent post-operative infections. we investigated the influence of the curing parameters (time and temperature) that allow control of the degree of functionalization (df) of the support by meβcd. the inclusion of ciprofloxacin (cfx) in the meβcd cavity was observed in solution by ...201120832508
infection acquisition following intensive care unit room privatization.patients in intensive care units (icus) often acquire infections, which impose a heavy human and financial burden. the use of private rooms may reduce the acquisition of certain pathogens, but the limited evidence on this topic is inconsistent.201121220658
the synthesis and characterization of poly(γ-glutamic acid)-coated magnetite nanoparticles and their effects on antibacterial activity and cytotoxicity.magnetite nanoparticles (mnps) modified with sodium and calcium salts of poly(γ-glutamic acid) (napga and capga) were synthesized by the coprecipitation method, followed by characterization and evaluation of their antibacterial and cytotoxic effects. superparamagnetic mnps are particularly attractive for magnetic driving as well as bacterial biofilm and cell targeting in in vivo applications. characterization of synthesized mnps by the fourier transform infrared spectra and magnetization curves ...201121233545
a photopolymerized antimicrobial hydrogel coating derived from epsilon-poly-l-lysine.hydrogels made from epsilon-poly-l-lysine-graft-methacrylamide (epl-ma) have been found to have impressive wide spectrum antimicrobial activity against both bacteria (specifically escherichia coli, pseudomonas aeruginosa, serratia marcescens and staphylococcus aureus) and fungi (specifically candida albicans and fusarium solani). the epl-ma hydrogel also possesses in vitro biocompatibility and epl-ma solution is relatively non-hemolytic: the concentration needed for onset of human red blood cell ...201121257199
unusual heme-binding pas domain from yybt family proteins.yybt family proteins (cog3887) are functionally unknown proteins that are widely distributed among the firmicutes, including the human pathogens staphylococcus aureus and listeria monocytogenes. recent studies suggested that yybt family proteins are crucial for the in vivo survival of bacterial pathogens during host infection. yybt family proteins contain an n-terminal domain that shares minimum sequence homology with per-arnt-sim (pas) domains. despite the lack of an apparent residue for heme c ...201121257773
pharmacodynamics of razupenem (pz601) studied in an in vitro pharmacokinetic model of infection.simulations of administration of razupenem at 1 g every 12 h by 1-h intravenous (i.v.) infusion were performed in an in vitro pharmacokinetic model of infection. the antibacterial effect of this razupenem dosing regimen against six strains of staphylococcus aureus (one methicillin-sensitive s. aureus [mssa] strain [mic, 0.015 µg/ml] and five methicillin-resistant s. aureus [mrsa] strains [mic range, 0.09 to 3 µg/ml]) and five strains of enterobacteriaceae (three escherichia coli strains [two con ...201121263054
surface display of human lactoferrin using a glycosylphosphatidylinositol-anchored protein of saccharomyces cerevisiae in pichia pastoris.a cell surface display system was developed in pichia pastoris using the gene tip1, encoding the glycosylphosphatidylinositol (gpi)-anchored protein of saccharomyces cerevisiae (sctip). human lactoferrin cdna (hlf) was fused to a full-length tip1 dna (sctip ( 630 )) or a short-tip1 fragment (sctip ( 120 )) encoding the 40 c-terminal amino acids of sctip. both hlf-sctip fusion genes were expressed in p. pastoris smd 1168. the fused protein was detected by western blotting after extraction of the ...201121267758
influenza coinfection and outcomes in children with complicated pneumonia.to determine the impact of influenza coinfection on outcomes for children with complicated pneumonia.201121300649
superantigens in dermatology.superantigens (sags) are virulent polypeptides that are produced by a variety of infectious organisms. they are capable of causing nonspecific t cell activation by circumventing normal antigen processing in the human host. the genetic makeup of the host plays a role in conferring susceptibility or protection against sags. they are linked to a variety of conditions, ranging from toxic shock syndrome to recurrent toxin-mediated perineal erythema. the early recognition of signs and symptoms of sag- ...201121315950
acute necrotic stomatitis (noma) associated with methicillin-resistant staphylococcus aureus infection in a newly acquired rhesus macaque (macaca mulatta).a newly acquired rhesus macaque was suffering from rapid destruction of the left cheek caused by necrotizing stomatitis.201121332756
purification of a lectin with antibacterial activity from bothrops leucurus snake venom.a novel lectin was isolated from bothrops leucurus snake venom using a combination of affinity and gel filtration chromatographies. the lectin (bll) agglutinated glutaraldehyde-treated rabbit and human erythrocytes with preference for rabbit erythrocytes. galactose, raffinose, lactose, fetal bovine serum and casein inhibited lectin-induced rabbit erythrocyte agglutination. bll, with a molecular mass of 30 kda and composed of two subunits of 15 kda, showed dependence on calcium. bll is an acidic ...201121334449
broad-spectrum antimicrobial efficacy of peptide a3-apo in mouse models of multidrug-resistant wound and lung infections cannot be explained by in vitro activity against the pathogens involved.although the designer proline-rich antimicrobial peptide a3-apo has only modest activity against escherichia coli and acinetobacter baumannii in vitro, in mouse models of systemic and wound infections it shows superior efficacy compared with conventional antibiotics. in this study, the efficacy of a3-apo in several additional mouse models was investigated, including staphylococcus aureus wound infection, mixed klebsiella pneumoniae-a. baumannii-proteus mirabilis wound infection and k. pneumoniae ...201121353493
lactobacillus reuteri-produced cyclic dipeptides quench agr-mediated expression of toxic shock syndrome toxin-1 in staphylococci.the production of the staphylococcal exotoxin toxic shock syndrome toxin-1 (tsst-1) by staphylococcus aureus has been associated with essentially all cases of menstruation-associated toxic shock syndrome (tss). in this work, we show that the human vaginal isolate lactobacillus reuteri rc-14 produces small signaling molecules that are able to interfere with the staphylococcal quorum-sensing system agr, a key regulator of virulence genes, and repress the expression of tsst-1 in s. aureus mn8, a pr ...201121282650
modeling antibiotic and cytotoxic effects of the dimeric isoquinoline iq-143 on metabolism and its regulation in staphylococcus aureus, staphylococcus epidermidis and human cells.abstract: background: xenobiotics represent an environmental stress and as such are a source for antibiotics, including the isoquinoline (iq) compound iq-143. here, we demonstrate the utility of complementary analysis of both host and pathogen datasets in assessing bacterial adaptation to iq-143, a synthetic analog of the novel type n,c-coupled naphthyl-isoquinoline alkaloid ancisheynine. results: metabolite measurements, gene expression data and functional assays were combined with metabolic mo ...201121418624
monitoring of multiple drug-resistant pathogens in a selected stretch of bay of bengal, india.the present work aims at identification of multiple drug-resistant pathogenic bacteria in a selected stretch, namely, puri on the bay of bengal, india. six stations at the coast of puri were selected and samples of water and sediment were collected during the winter of 2008 and 2009 for this study. thirty-eight pathogenic bacteria were isolated and identified from both the water and the sediment of 6 fixed stations (pu-1a, pu-1b, pu-2, pu-3, pu-4, and pu-5). the identified pathogens were escheri ...201121424669
susceptibility of clinical staphylococcus aureus isolates to innate defense antimicrobial peptides.antimicrobial peptides (amps) are effector molecules of innate immunity. to determine whether amp susceptibility of s. aureus varies according to different types of infection, 102 isolates from patients with s. aureus bacteremia or recurrent skin and soft tissue infection, and colonizing isolates were investigated. using microbroth dilution assays we found a narrow range of mics of human β-defensin-3, cathelicidin ll-37 and bovine indolicidin without significant differences between the groups. c ...201121473929
characterization of staphylococcus aureus strains involved in human and bovine mastitis.staphylococcus aureus is one of the main etiological agents of mastitis in different mammalian species. at present, it is unknown whether strains isolated from human mastitis cases share phenotypic properties and genetic background with those obtained from animal mastitis cases. therefore, the objective of this study was to characterize s. aureus strains isolated from women with lactational mastitis and to compare them with the strains responsible for bovine mastitis and noninfectious strains. a ...201121477005
occurrence of genes of putative fibrinogen binding proteins and hemolysins, as well as of their phenotypic correlates in isolates of s. lugdunensis of different origins.abstract:201121477287
antibacterial activity in spices and local medicinal plants against clinical isolates of karachi, pakistan.context: development of resistance in human pathogens against conventional antibiotic necessitates searching indigenous medicinal plants having antibacterial property. twenty-seven medicinal plants used actively in folklore, ayurvedic and traditional system of medicine were selected for the evaluation of their antimicrobial activity for this study. eleven plants chosen from these 27 are used as spices in local cuisine. objective: evaluation of the effectiveness of some medicinal plant extracts a ...201121501041
exoproteome of staphylococcus aureus reveals putative determinants of nasal carriage.due to the increasing prevalence of nosocomial and community-acquired antibiotic resistant staphylococcus aureus (sa), understanding the determinants of sa nasal carriage has become a major imperative. previous research has revealed many host and bacterial factors that contribute to sa nasal carriage. to assess bacterial factors that facilitate nasal carriage, we compared the exoproteome of a nasal carrier strain of sa to a genetically similar noncarrier strain. additionally, the carrier strain ...201121338050
inference of the transcriptional regulatory network in staphylococcus aureus by integration of experimental and genomics-based evidence.transcriptional regulatory networks are fine-tuned systems, which help microorganisms respond to changes in the environment and cell physiological state. we applied the comparative genomics approach implemented in the regpredict web-server combined with seed subsystem analysis and available information on known regulatory interactions for regulatory network reconstruction in the human pathogen staphylococcus aureus and six related species from the staphylococcaceae family. the resulting referenc ...201121531804
studies on in vitro antioxidant and antistaphylococcal activities of some important medicinal plants.oxidative stress is initiated by free radicals, which seek stability through electron pairing with biological macromolecules in healthy human cells and cause protein and dna damage along with lipid peroxidation. many phytochemicals have been found to play as potential antioxidants and antimicrobials. in the present study antioxidant and antistaphylococcal activities of bauhinia variegata, tinospora cardifolia and piper longum have been determined. total phenolic contents in plant extracts were e ...201121366958
a modulatory interleukin-10 response to staphylococcal peptidoglycan prevents th1/th17 adaptive immunity to staphylococcus aureus.toll-like receptor (tlr) 2 on antigen-presenting cells (apcs) enables these cells to recognize peptidoglycan-embedded lipopeptides and glycopolymers in the staphylococcus aureus cell wall and mount an inflammatory response to this microbe. tlr2 signalling can also modulate immunity to s. aureus by inducing an interleukin (il)-10 response in apcs. what determines the balance between proinflammatory and modulatory responses to s. aureus is unknown. we show that the modulatory il-10 response prefer ...201121673036
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