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Vancomycin
Terms modified by Vancomycin Selected AbstractsMycotic aneurysm of the renal transplant arteryINTERNATIONAL JOURNAL OF UROLOGY, Issue 6 2006SHIRO FUJIKATA Abstract, A case of mycotic aneurysm secondary to septicemia is reported. A 59-year-old man with end-stage renal failure underwent renal transplantation from a living donor. On the fifteenth postoperative day, he was febrile and his arm around an entry wound of the drip infusion had infectious signs. Cultures of the blood and pus discharge grew Methicillin-resistant Staphylococcus aureus. Vancomycin was administered intravenously for 30 days. Then the existence of a mycotic aneurysm on the transplant artery was not suspected by computed tomography. After his infectious signs disappeared, examinations revealed a pseudoaneurysm measuring 4 cm in diameter at the site of anastomosis between the renal transplant and external iliac arteries by computed tomography. He has been carefully followed up with a conservative management. This is the first case of a mycotic aneurysm treated conservatively and displaying an uneventful course without rupture. [source] Antibiotics modulate the stimulated cytokine response to endotoxin in a human ex vivo, in vitro modelACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 9 2006S. Ziegeler Background:, Sepsis may lead to the suppression of stimulated cytokine release after Gram-negative stimuli, correlating with a fatal outcome. Treatment of sepsis includes adequate therapy with antibiotics. The aim of this study was to investigate the role of antibiotics in the modulation of the lipopolysaccharide (LPS)-stimulated cytokine response of human monocytes. Methods:, In this ex vivo, in vitro study, whole blood samples were taken from 10 healthy volunteers, stimulated with LPS in the presence or absence of various antibiotics (penicillin, amoxicillin, cefuroxime, ceftazidime, cefotaxime, piperacillin/tazobactam, imipenem/cilastatin, gentamicin, netilmicin, ciprofloxacin, vancomycin) and cultured for 24 h. Thereafter, tumor necrosis factor-, (TNF-,) and interleukin-10 (IL-10) were measured in the supernatants by enzyme-linked immunosorbent assay (ELISA). Furthermore, CD14 and HLA-DR expression on monocytes was assessed using flow cytometry. Results:, All cephalosporins decreased LPS-stimulated IL-10 release. Cefuroxime and cefotaxime also decreased the expression density of the LPS recognition molecule CD14 on monocytes. An increase in LPS-stimulated IL-10 release was observed with vancomycin. A suppression of LPS-stimulated TNF-, and IL-10 release was observed in the presence of ciprofloxacin. Conclusion:, These results indicate a modulation of the expression density of CD14 on monocytes, together with a shift from a balanced to an inflammatory cytokine release pattern, by cefuroxime and cefotaxime. Vancomycin changes the response to an anti-inflammatory release pattern. After ciprofloxacin, a profound unresponsiveness of immune-competent cells to LPS stimulation is observed. Because of the critical role of a balanced innate immune response, these data may be of importance for the selection of antibiotics in septic patients. [source] Fulminant Liver Failure After Vancomycin in a Sulfasalazine-Induced DRESS Syndrome: Fatal Recurrence After Liver TransplantationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 9 2009M. Mennicke DRESS syndrome (drug rash with eosinophilia and systemic symptoms) is a rare drug hypersensitivity reaction with a significant mortality. We describe a 60-year-old man with polyarthritis treated with sulfasalazine who developed DRESS and fulminant liver failure after additional vancomycin treatment. Liver histology revealed infiltration of granzymeB+ CD3+ lymphocytes in close proximity to apoptotic hepatocytes. After a superurgent liver transplantation and initial recovery, the patient developed recurrent generalized exanthema and eosinophilia, but only moderate hepatitis. Histology showed infiltration of FasL+ lymphocytes and eosinophils in the transplanted liver. Treatment with high-dose methylprednisolone was unsuccessful. Postmortem examination revealed extensive necrosis of the liver transplant. This case report illustrates that patients with DRESS may develop fulminant liver failure and that DRESS recurrence can recur in the transplanted liver. Histological and immunological investigations suggest an important role of granzymeB and FasL mediated cell death in DRESS associated hepatitis. [source] Binaphthyl-Based Dicationic Peptoids with Therapeutic Potential,ANGEWANDTE CHEMIE, Issue 3 2010Mittel gegen Superbugs? Zwei neue synthetische dikationische Peptoide (siehe Beispiel; rot O, blau N, grün Cl) zeigen vielversprechende antibakterielle Aktivität in vitro gegen etliche Gram-positive Pathogene , einschließlich Vancomycin-, Methicillin- und Linezolid-resistenter Organismen , bei nur langsamer Resistenzentwicklung. Ihre Wirksamkeit bleibt darüber hinaus auch in vivo erhalten. [source] Donor-Bound Glycosylation for Various Glycosyl Acceptors: Bidirectional Solid-Phase Semisynthesis of Vancomycin and Its DerivativesCHEMISTRY - AN ASIAN JOURNAL, Issue 1 2007Takayuki Doi Prof. Abstract The glycosidation of a polymer-supported glycosyl donor, N -phenyltrifluoroacetimidate, with various glycosyl acceptors is reported. The application of the polymer-supported N -phenyltrifluoroacetimidate is demonstrated in the synthesis of vancomycin derivatives. 2- O -[2-(azidomethyl)benzoyl]glycosyl imidate was attached to a polymer support at the 6-position by a phenylsulfonate linked with a C13 alkyl spacer. Solid-phase glycosidation with a vancomycin aglycon, selective deprotection of the 2-(azidomethyl)benzoyl group, and glycosylation of the resulting 2-hydroxy group with a vancosamine unit were performed. Nucleophilic cleavage from the polymer support with acetate, chloride, azido, and thioacetate ions provided vancomycin derivatives in pure form after simple purification. The semisynthesis of vancomycin was achieved by deprotection of the acetate derivative. [source] Capillary Electrophoresis for the Simultaneous Determination of Metals by Using Ethylenediamine Tetraacetic Acid as Complexing Agent and Vancomycin as Complex SelectorCHINESE JOURNAL OF CHEMISTRY, Issue 12 2006Jirasak Threeprom Abstract A new separation system of capillary electrophoresis for the simultaneous determination of metals by using ethylenediamine tetraacetic acid (EDTA) as complexing agent and employing vancomycin as complex selector was described. The Z-shape cell capillary electrophoresis was used to enhance the sensitivity for the determination of the complexes of Cu(II), Ni(II), Co(II) and Fe(III) with EDTA. The partial filling method (co-current mode) was used in order to increase the selectivity of the electrophoretic method, meanwhile vancomycin was not present at the detector path during the detection of metal-EDTA complexes. The vancomycin concentration, phosphate concentration and pH of the buffer strongly influenced mobility, resolution and selectivity of the studied analytes. Under the optimal condition, the relative standard deviations (n=5) of the migration time and the peak area were less than 3.14% and 7.35%, respectively. Application of the Z-shape cell capillary electrophoresis method with UV detection and vancomycin loading led to the reliable determination of these metal ions in tap water and the recoveries were97%,101%. The detection limits based on a signal to noise ratio of 3:1 were found in the range of 2,10 µg·L,1. [source] Cutaneous infections in the elderly: diagnosis and managementDERMATOLOGIC THERAPY, Issue 3 2003Jeffrey M. Weinberg ABSTRACT:, Over the past several years there have been many advances in the diagnosis and treatment of cutaneous infectious diseases. This review focuses on the three major topics of interest in the geriatric population: herpes zoster and postherpetic neuralgia (PHN), onychomycosis, and recent advances in antibacterial therapy. Herpes zoster in adults is caused by reactivation of the varicella-zoster virus (VZV) that causes chickenpox in children. For many years acyclovir was the gold standard of antiviral therapy for the treatment of patients with herpes zoster. Famciclovir and valacyclovir, newer antivirals for herpes zoster, offer less frequent dosing. PHN refers to pain lasting ,2 months after an acute attack of herpes zoster. The pain may be constant or intermittent and may occur spontaneously or be caused by seemingly innocuous stimuli such as a light touch. Treatment of established PHN through pharmacologic and nonpharmacologic therapy will be discussed. In addition, therapeutic strategies to prevent PHN will be reviewed. These include the use of oral corticosteroids, nerve blocks, and treatment with standard antiviral therapy. Onychomycosis, or tinea unguium, is caused by dermatophytes in the majority of cases, but can also be caused by Candida and nondermatophyte molds. Onychomycosis is found more frequently in the elderly and in more males than females. There are four types of onychomycosis: distal subungual onychomycosis, proximal subungual onychomycosis, white superficial onychomycosis, and candidal onychomycosis. Over the past several years, new treatments for this disorder have emerged which offer shorter courses of therapy and greater efficacy than previous therapies. The treatment of bacterial skin and skin structure infections in the elderly is an important issue. There has been an alarming increase in the incidence of gram-positive infections, including resistant bacteria such as methicillin-resistant Staphylococcus aureus (MRSA) and drug-resistant pneumococci. While vancomycin has been considered the drug of last defense against gram-positive multidrug-resistant bacteria, the late 1980s saw an increase in vancomycin-resistant bacteria, including vancomycin-resistant enterococci (VRE). More recently, strains of vancomycin-intermediate resistant S. aureus (VISA) have been isolated. Gram-positive bacteria, such as S. aureus and Streptococcus pyogenes are often the cause of skin and skin structure infections, ranging from mild pyodermas to complicated infections including postsurgical wound infections, severe carbunculosis, and erysipelas. With limited treatment options, it has become critical to identify antibiotics with novel mechanisms of activity. Several new drugs have emerged as possible therapeutic alternatives, including linezolid and quinupristin/dalfopristin. [source] Inhibition of the D -alanine:D -alanyl carrier protein ligase from Bacillus subtilis increases the bacterium's susceptibility to antibiotics that target the cell wallFEBS JOURNAL, Issue 12 2005Juergen J. May The surface charge as well as the electrochemical properties and ligand binding abilities of the Gram-positive cell wall is controlled by the d -alanylation of the lipoteichoic acid. The incorporation of d -Ala into lipoteichoic acid requires the d -alanine:d -alanyl carrier protein ligase (DltA) and the carrier protein (DltC). We have heterologously expressed, purified, and assayed the substrate selectivity of the recombinant proteins DltA with its substrate DltC. We found that apo-DltC is recognized by both endogenous 4,-phosphopantetheinyl transferases AcpS and Sfp. After the biochemical characterization of DltA and DltC, we designed an inhibitor (d -alanylacyl-sulfamoyl-adenosine), which is able to block the d -Ala adenylation by DltA at a Ki value of 232 nmin vitro. We also performed in vivo studies and determined a significant inhibition of growth for different Bacillus subtilis strains when the inhibitor is used in combination with vancomycin. [source] Adhesion of Enterococcus faecalis 1131 grown under subinhibitory concentrations of ampicillin and vancomycin to a hydrophilic and a hydrophobic substratumFEMS MICROBIOLOGY LETTERS, Issue 1 2001Amparo M Gallardo-Moreno Abstract The effect of two subinhibitory antibiotic concentrations of ampicillin and vancomycin during growth on the adhesion of Enterococcus faecalis 1131 to glass and silicone rubber was studied in a parallel plate flow chamber. Initial deposition rates and numbers of adhering bacteria after 4 h were higher on hydrophilic glass than on hydrophobic silicone rubber, regardless of growth conditions. The presence of 1/4 minimal inhibitory concentration (MIC) of ampicillin during growth reduced enterococcal adhesion to both substrata, but growth in the presence of 1/4 MIC vancomycin did not affect the adhesion of E. faecalis. Moreover, enterococcal adhesion increased after growth in the presence of 1/8 MIC vancomycin. The increased adhesion after growth in the presence of subinhibitory concentrations of vancomycin may have strong implications for patients living with implanted biomaterials, as they may suffer adverse effects from use of this antibiotic, especially since bacteria once adhered are less sensitive to antibiotics. [source] Simultaneous Immobilization of Bioactives During 3D Powder Printing of Bioceramic Drug-Release MatricesADVANCED FUNCTIONAL MATERIALS, Issue 10 2010Elke Vorndran Abstract The combination of a degradable bioceramic scaffold and a drug-delivery system in a single low temperature fabrication step is attractive for the reconstruction of bone defects. The production of calcium phosphate scaffolds by a multijet 3D printing system enables localized deposition of biologically active drugs and proteins with a spatial resolution of approximately 300,µm. In addition, homogeneous or localized polymer incorporation during printing with HPMC or chitosan hydrochloride allows the drug release kinetics to be retarded from first to zero order over a period of 3,4 days with release rates in the range 0.68%,0.96%,h,1. The reduction in biological activity of vancomycin, heparin, and rhBMP-2 following spraying through the ink jet nozzles is between 1% and 18%. For vancomycin, a further loss of biological activity following incorporation into a cement and subsequent in vitro release is 11%. While previously acknowledged as theoretically feasible, is its shown for the first time that bone grafts with simultaneous geometry, localized organic bioactive loading, and localized diffusion control are a physical reality. This breakthrough offers a new future for patients by providing the required material function to match patient bone health status, site of repair, and age. [source] Structures of Four Crystal Forms of DecaplaninHELVETICA CHIMICA ACTA, Issue 5 2003Christopher Lehmann The glycopeptide antibiotic decaplanin (1; formerly known as MM 47761 and M86-1410) crystallizes in two P21 and two P6122 crystal forms, each with four monomers in the asymmetric unit, with solvent contents varying from 48 to 69%. Although with ca. 600 unique atoms, the structures are larger than typical small molecules, one was solved by direct methods. The other three were solved by typical macromolecular methods: single-wavelength anomalous diffraction (SAD) of the Cl-atoms present naturally in the structure, multiple-wavelength anomalous diffraction (MAD) at the Br absorption edge for a crystal soaked in NaBr solution, and molecular replacement. There is evidence of appreciable radiation damage with loss of 20,30% of the covalent and ionic halogens affecting the synchrotron datasets that may even have unintentionally facilitated the MAD structure solution. The structures contain the dimer units typical of antibiotics related to vancomycin, but, in addition, there are a variety of further intermolecular interactions responsible for the polymorphy leading to intertwined 61 -helices in two of the crystal forms. Except for the sugars and some sidechains, the conformations of the 16 independent monomers are very similar. [source] Regional audit: Perioperative management of MRSA orthopaedic patients in the Oxford regionINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 5 2004N. Aslam Summary Aim:, Methicillin resistant staphylococcus aureus (MRSA) colonisation or infection is of particular importance in patients undergoing operations involving implanteable materials, such as in orthopaedic surgery. An audit of the perioperative management of orthopaedic patients in the Oxford region was carried out to assess the level of clinician awareness and the uniformity of current guidelines between hospitals. Methods:, A postal questionnaire was designed for asking information on various aspects of perioperative management of MRSA patients and was sent to each hospital. Results:, Responses were obtained from nine of 10 hospitals in the region. The average response rate for each hospital was 75%, and the overall individual response rate was 67.5% (27/40). Seventy-eight per cent of respondents knew that there was a pre-admission screening policy. Fifteen per cent were unaware of any MRSA policy. Forty-four per cent indicated that teicoplanin was used for prophylaxis in implant surgery whilst 44% used vancomycin. Eighteen per cent believed that cefuroxime was used for prophylaxis. Forty-eight per cent of hospitals had an MRSA-free zone for orthopaedic patients. Conclusion:, This study indicates a lack of uniformity in the perioperative management of MRSA-positive patients in the region and a lack of awareness of both MRSA guidelines and their implementation. Uniformity of MRSA guidelines is necessary to allow better clinician awareness and compliance, especially in surgical trainees who are travelling between different training hospitals in the region. Implementation of such a policy with re-audit of subsequent awareness and compliance is proposed. [source] Combining Fluorescent Probes and Biofunctional Magnetic Nanoparticles for Rapid Detection of Bacteria in Human Blood,ADVANCED MATERIALS, Issue 23 2006J. Gao Detection of bacteria in human blood within two hours is achieved through the use of vancomycin-functionalized FePt nanoparticles in combination with a vancomycin-conjugated fluorescent probe, as shown in the figure (B: bacteria; Van: vancomycin; FLA: fluorescein amine). This promises to be a sensitive and rapid protocol for detecting bacteria in blood products or other targets in biological samples. [source] ,1-Antitrypsin deficiency presenting with panniculitis and incidental discovery of chronic obstructive pulmonary diseaseINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 10 2007Gretchen Korver MD A 60-year-old man presented to the Emergency Department (ED) with large, painful, indurated plaques on the right thigh, left abdomen, left chest, and right chest, which began without any preceding trauma on the right thigh 3 weeks prior to presentation in the ED. He was initially treated with cefazolin 1 g three times daily as home infusions. When the lesions continued to progress, he was admitted to the hospital and placed on amoxicillin/clavulanate and vancomycin. He had a single episode of fever of 102°F, but his white blood cell count and differential remained normal. An initial biopsy showed a dermal inflammatory infiltrate composed primarily of neutrophils and eosinophils with rare flame figures in the dermis. There was minimal fat seen in this biopsy. A differential diagnosis of Wells or Sweet's syndrome was entertained, and he was placed on 60 mg/day prednisone with no resolution of his symptoms. The patient's past medical history included hypertension, hyperlipidemia, peripheral neuropathy, and hiatal hernia. His family history was significant for emphysema in both parents and coronary artery disease in his father. Both of his parents smoked cigarettes. His grandfather, who was a coal miner, also had emphysema. Whilst on antibiotics and prednisone, the plaques on the patient's right thigh, right abdomen, and left chest expanded and ulcerated, draining an oily liquid (Figs 1 and 2). An incisional biopsy was obtained from his thigh. Histopathology showed a septal and lobular panniculitis with fat necrosis, neutrophils, and histiocytes (Fig. 3). Special stains for organisms were negative. Tissue sent for bacterial and fungal culture had no growth. Amylase and lipase levels were normal. Rheumatoid factor, antinuclear antibody (ANA), antineutrophil cytoplasmic antibody (ANCA), cryoglobulins, and antiphospholipid antibodies were all normal. The ,1-antitrypsin level was low at 25 mg/dL (ref. 75,135). The ,1-antitrypsin phenotype was PiZZ. Figure 1. Indurated plaques on right chest and thigh and left chest Figure 2. Ulcerated plaques on left chest Figure 3. Septal and lobular panniculitis with fat necrosis. Hematoxylin and eosin ×10 The patient had a normal glucose-6-phosphate dehydrogenase level and was placed on dapsone 200 mg/day. The inflammation resolved and, over the course of several months, the involved areas healed with scarring. The patient denied any pulmonary complaints but, during his hospitalization, was found incidentally to have an oxygen saturation of 88% on room air. He was sent for evaluation by a pulmonologist, and pulmonary function tests revealed a mixed restrictive and obstructive pattern with a forced expiratory volume in 1 to forced vital capacity (FEV1/FVC) ratio of 63% of predicted. He had never smoked. He was placed on supplemental oxygen but, as his pulmonary disease has been stable, he has not been treated with intravenous antitrypsin inhibitor. [source] Frequent occurrence of multidrug-resistant CC17 Enterococcus faecium among clinical isolates in SwedenJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2010H. Billström Abstract Aims:, To screen for the globally spread cluster of Enterococcus faecium, clonal complex 17 (CC17) and characterize the genetic profile of Swedish clinical Ent. faecium isolates. Methods:, A total of 203 consecutive isolates collected from 2004 to 2007 from patients with bacteraemia in Sweden. All isolates were genotyped using multiple-locus variable-number tandem repeat analysis (MLVA) and 20 isolates representing different MLVA types (MT) were chosen for multilocus sequence typing (MLST). Minimal inhibitory concentrations against clinically relevant antibiotics were determined with agar dilution. Presence of the virulence genes esp and hyl was investigated using PCR. Results:, A total of 65% (n = 109) of all isolates belonged to MT-1, and the second most common MLVA type was MT-159 (13%, n = 21). MLST analysis confirmed the presence of CC17 during the entire study period. The number of isolates resistant to gentamicin and vancomycin, as well as the presence of hyl, increased significantly during the investigation period. Conclusions:, The present study demonstrates that nosocomial infections caused by Ent. faecium CC17 are commonly occurring in Sweden. Significance and Impact of the Study:, This is the first report of CC17 Ent. faecium in Sweden. The increase of antibiotic resistance and virulence indicates that these strains are further adapting to the hospital environment. [source] Growth of pure cultures of Verocytotoxin-producing Escherichia coli in a range of enrichment mediaJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2008C.L. Baylis Abstract Aims:, This study compared the growth of different strains of Verocytotoxin-producing Escherichia coli (VTEC) in a range of selective enrichment media. Methods and Results:, Turbidometric and impedance methods were used to determine the growth of VTEC in pure culture in different enrichment media. Ten strains failed to grow in buffered peptone water + vancomycin, cefsulodin, cefixime at 42°C and some failed to grow, or grew poorly in E. coli (EC) medium supplemented with 20 mg l,1 novobiocin and modified EC supplemented with 20 mg l,1 novobiocin at 37°C and 42°C. Individual VTEC strains were sensitive to the selective agents in some media. Statistical analysis of the conductance detection times of 10 strains showed no overall effect of temperature alone (P = 0·66) but there were significant (P < 0·001) effects as a result of the combination of medium and temperature and these two factors were influenced by strain. Conclusions:, Growth of VTEC during enrichment is dependent on different factors alone or in combination. These include medium type, presence of certain selective agents or antibiotics, incubation temperature and the initial population of VTEC. Sensitivity to these conditions can be strain related. Significance and Impact of the Study:, This study highlighted differences in the ability of some enrichment media to support the growth of VTEC, making them unsuitable for the isolation of VTEC, especially low numbers of non-O157 strains. [source] A comparison of two pre-enrichment media prior to immunomagnetic separation for the isolation of E. coli O157 from bovine faecesJOURNAL OF APPLIED MICROBIOLOGY, Issue 1 2003G. Foster Abstract Aims: To compare the sensitivity of two pre-enrichment broth media prior to immunomagnetic separation for the isolation of Escherichia coli O157 from cattle faeces. Methods and Results: One-gram portions of 721 cattle faeces collected from 43 farms were pre-enriched in buffered peptone water containing vancomycin, cefixime and cefsulodin (BPW-VCC) and buffered peptone water without additives (BPW-WOA), respectively. A total of 137 samples were positive for E. coli O157: 127 pre-enriched with BPW-WOA and 89 pre-enriched in BPW-VCC. Representative isolates were tested for phage type, verotoxin and eae (E. coli attaching and effacing) gene sequences, resulting in the recognition of eight different types. All the E. coli O157 types recognized were isolated by both methods except for three different strains, each of which were isolated only on a single occasion: two by BPW-WOA and another by BPW-VCC. Conclusions: The results clearly demonstrate, under the conditions of this study, that BPW without antibiotics was the superior pre-enrichment medium for the isolation of E. coli O157 from cattle faeces. Significance and Impact of the Study: The use of BPW-WOA in preference to BPW-VCC for the isolation of E. coli O157 from cattle faeces in future research and outbreak studies should lead to a higher number of positive isolates. [source] Hollow, pH-sensitive calcium,alginate/poly(acrylic acid) hydrogel beads as drug carriers for vancomycin releaseJOURNAL OF APPLIED POLYMER SCIENCE, Issue 4 2010Hong-Ru Lin Abstract In this study, hollow calcium,alginate/poly(acrylic acid) (PAA) hydrogel beads were prepared by UV polymerization for use as drug carriers. The hollow structure of the beads was fortified by the incorporation of PAA. The beads exhibited different swelling ratios when immersed in media at different pH values; this demonstrated that the prepared hydrogel beads were pH sensitive. A small amount (<9%) of vancomycin that had been incorporated into the beads was released in simulated gastric fluid, whereas a large amount (,67%) was released in a sustained manner in simulated intestinal fluid. The observed drug-release profiles demonstrated that the prepared hydrogel beads are ideal candidate carriers for vancomycin delivery into the gastrointestinal tract. Furthermore, the biological response of cells to these hydrogel beads indicated that they exhibited good biological safety and may have additional applications in tissue engineering. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source] Intermittent watt-level ultrasonication facilitates vancomycin release from therapeutic acrylic bone cementJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2009Xun-Zi Cai Abstract Ultrasound holds promise for enhancing the vancomycin release from cement though the length of time when local drug level exceeded the minimum inhibitory concentration (T>MIC) was not prolonged by the previous protocol of milliwatt-level ultrasonication. Here vancomycin-loaded cements were subjected to continuous watt-level ultrasonication (CUG), intermittent watt-level ultrasonication (IUG) or no ultrasonication (NUG) for 14 d during immersion in 40-ml phosphate buffered saline (PBS) for 28 d. The T>MIC for IUG was more than three times that for NUG. In contrast, T>MIC for CUG was slightly shortened. The subtherapeutic release of vancomycin between 15 d and 28 d for IUG was one-ninth that for NUG. The fitting equations indicated a significant enhancement on the burst release and the slow release for IUG; however, the continuous ultrasonication hampered the slow release. SEM images exhibited denser craters and pores with larger diameters and less residual drug in specimens from IUG relative to those from both CUG and NUG. Intermittent watt-level ultrasonication improved the ultrasound-enhanced vancomycin release from cement in view of the prolonged T>MIC and the inhibited subtherapeutic release compared with continuous ultrasonication. The mechanisms may be associated with the distinctive effects of detaching forces and pushing forces by acoustic microstreams. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009 [source] Preparation and characterization of infection-resistant antibiotics-releasing hydrogels rods of poly[hydroxyethyl methacrylate- co -(poly(ethylene glycol)-methacrylate]: Biomedical application in a novel rabbit penile prosthesis modelJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2008M. Yakup Ar Abstract In this work, preparation and characterization of novel three different antibiotic loaded penile prosthesis in the rod form were investigated by copolymerization of 2-hydroxyethylmethacrylate (HEMA) with poly(ethylene glycol)-methacrylate, (PEG-MA). To achieve this goal, a series of novel copolymer hydrogels were prepared in rod form using HEMA and PEG-MA monomers via UV initiated photopolymerization. The thermal stability of the copolymer was found to be lowered by increase in the ratio of PEG-MA in the rod structure. Contact angle measurements on the surface of copolymer hydrogel demonstrated that the copolymer gave rise to a significant hydrophilic surface compared with pure poly(HEMA). The blood protein adsorption and platelet adhesion were significantly reduced on the surface of the copolymer hydrogels compared with control pure poly(HEMA). Poly(HEMA:PEG-MA;1:1)-1 formulation containing different antibiotics (20 mg antibiotic/g polymer) released about 90, 91, and 55% of the total loaded cephtriaxon, vancomycin, and gentamicin in 48 h at pH 7.4, respectively. Finally, antibiotics loaded biocompatible poly(HEMA:PEG-MA;1:1)-1 hydrogel compositions was used as a penile prosthesis in preventing cavernous tissue infections in a rabbit prosthesis model. The efficacy of the three different antibiotics loaded hydrogel system was evaluated in four different groups of rabbits, in which various infectious agents were inoculated. The animals were sacrificed after predetermined time periods, and clinical, histological and microbiological assessment on the implant side were carried out to detect infections. Eventually, we concluded that three different antibiotic loaded penile prostheses (i.e. poly(HEMA:PEG-MA;1:1)-1 hydrogel systems) were as effective as parenteral antibiotics applications. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008 [source] ORIGINAL ARTICLE: Investigation of the prediction accuracy of vancomycin concentrations determined by patient-specific parameters as estimated by Bayesian analysisJOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 5 2010Y. Hiraki BSc Summary Background/Objective:, There have been many studies of therapeutic drug monitoring (TDM) of vancomycin (VCM) based on Bayesian analysis, but there have been no reports of the accuracy of prediction based on Bayesian-estimated patient-specific parameters. This study was conducted to compare the accuracy of prediction based on the population pharmacokinetic (PPK) method and Bayesian-estimated parameters. Method:, The subjects were 22 patients who were treated with VCM for MRSA infection and whose blood was sampled twice or more during the administration period. The concentrations between the blood samples were predicted based on the concentrations in the first blood samples based on the PPK method using mean parameters for the Japanese population and Bayesian-estimated patient-specific pharmacokinetic parameters. The mean prediction error (ME), mean absolute error (MAE) and root mean squared error (RMSE) were compared to examine the accuracy of prediction based on Bayesian-estimated patient-specific parameters. Results and discussion:, The mean measured VCM concentration was 10·43 ± 5·19 ,g/mL, whereas the mean concentration predicted based on the PPK method was 8·52 ± 4·34 ,g/mL, with an ME of ,1·91, MAE of 2·93 and RMSE of 3·21. The mean concentration predicted based on patient-specific parameters was 9·62 ± 4·95 ,g/mL with ME of ,0·81, MAE of 1·38 and RMSE of 1·74. The ME and MAE for the concentrations predicted using patient-specific parameters were smaller compared with those predicted using the PPK method (P = 0·0471 and 0·0003, respectively), indicating superior prediction with a significant difference between approaches. Conclusion:, Prediction using Bayesian estimates of patient-specific parameters was better than by the PPK method. However, when using patient-specific parameters it is still necessary to fully understand the clinical status of the patient and frequently determine VCM concentrations. [source] Effect of various estimates of renal function on prediction of vancomycin concentration by the population mean and Bayesian methodsJOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 4 2009Y. Tsuji BSc Summary Objective:, Renal function was estimated in 129 elderly patients with methicillin-resistant Staphylococcus aureus (MRSA) who were treated with vancomycin (VCM). The estimation was performed by substituting serum creatinine (SCR) measured enzymatically and a value converted using the Jaffe method into the Cockcroft-Gault and Modification of Diet in Renal Disease (MDRD) equations. The serum trough level was predicted from three estimates of renal function by the population mean (PM) and Bayesian methods and the predictability was assessed. Methods:, Two-compartment model-based Japanese population parameters for VCM were used, and the mean prediction error (ME) and root mean squared error (RMSE) were calculated as indices of bias and accuracy, respectively, for predictions by the PM and Bayesian methods. Results:, The PM method gave the highest correlation with the measured value using the estimate of renal function obtained by substituting the Jaffe-converted SCR into the Cockcroft-Gault equation. There was no positive or negative bias in the ME and the value was significantly smaller than for other predicted data (P < 0·05). RMSE was also the smallest, indicating that this method increases the predictability of the serum VCM trough level. While, ME showed a negative bias for all values predicted by the Bayesian method, both the ME and RMSE were very small. Conclusion:, In the application of the PM method for VCM treatment of elderly patients with MRSA, substitution of SCR based on the Jaffe method into the Cockcroft-Gault equation increases the predictability of the serum VCM trough level. The Bayesian method predicted the serum VCM trough level with high accuracy using any of the estimates of renal function. [source] PREVALENCE AND ANTIMICROBIAL RESISTANCE OF LISTERIA SPECIES IN FOOD PRODUCTS IN BANGKOK, THAILANDJOURNAL OF FOOD SAFETY, Issue 1 2010SIRIPORN STONSAOVAPAK ABSTRACT A total of 380 meat and meat products, dairy and dairy products, fresh vegetables, fresh seafood, and ready-to-eat food samples from supermarkets in Bangkok, Thailand were collected and analyzed for the occurrence of Listeria spp. and of Listeria monocytogenes. The overall incidence of Listeria spp. was 16.8%, most of them were isolated from raw meat and vegetables. L. monocytogenes was isolated from 18 (4.7%) out of 380 studied samples. Other species isolated were L. innocua (6.6%), L. ivanovii (0.8%), L. seeligeri (0.5%), L. grayi (1.6%) and L. welshimeri (2.6%). The antimicrobial susceptibilities of the 64 isolate of Listeria spp. were also examined by the standard disk diffusion method. Listeria spp. were resistant to penicillin (6.3%), chloramphenicol (3.1%) and tetracycline (1.6%), but sensitive to amoxicillin, vancomycin, ampicillin, rifampicin and sulfamethoxazole. PRACTICAL APPLICATIONS Listeria monocytogenes prevalence in food products in Bangkok has been documented. More studies on the occurrence of L. monocytogenes are needed to establish microbiological criteria of foods in the country. The findings of our study, increases in antibiotic resistance among Listeria spp. will provide useful information for the development of public health policy in the use of antimicrobials in food animal production. [source] INCIDENCE AND CHARACTERIZATION OF BACILLUS CEREUS IN MEAT AND MEAT PRODUCTS CONSUMED IN TURKEYJOURNAL OF FOOD SAFETY, Issue 1 2006KIYMET GÜVEN ABSTRACT A total of 100 retail samples of meat and meat products were examined for Bacillus cereus using mannitol egg yolk polymyxin (MYP) agar as a selective isolation medium. Only 22.4% of the samples contained detectable levels of B. cereus, with counts ranging from log10 0.69 to 4.80 cfu/g, but a large number of other organisms up to log10 9.06 cfu/g were sometimes observed on the plates and may have masked the presence of B. cereus or inhibited growth. Two samples of soudjouck contained significant levels of B. cereus, sufficient enough to create a public health hazard. Selected isolates were tested for diarrheal enterotoxin production by a reversed passive latex agglutination (RPLA) test kit. Results showed no difference in the toxin production of B. cereus between beef, ground meat, soudjouck and pastrami samples. Plasmid-profile analysis and susceptibility to the six commonly used antimicrobial agents were done on selected B. cereus isolates. About 96.4% of the isolates contained plasmids. Plasmid sizes ranged between 2.5 and 3.5 kb. The isolates showed a high rate of resistance to oxacillin (OXA) and amoxicillin (AMC) and a low frequency of resistance to the other antimicrobial agents, with all of them being susceptible to vancomycin (VAN). Approximately 54% of the isolates showed multiple resistance. There was no apparent relationship between drug resistance and carriage of plasmids. [source] Subtractive Screening for Probiotic Properties of Lactobacillus Species from the Human Gastrointestinal Tract in the Search for New ProbioticsJOURNAL OF FOOD SCIENCE, Issue 8 2007S. Delgado ABSTRACT:, In the search for new probiotics, 61 Lactobacillus spp. isolates, belonging to 12 species and isolated as dominant lactic acid bacteria from the feces of healthy humans, were subjected to a subtractive system of in vitro analyses, which included desirable and undesirable traits. Twenty-four isolates were able to grow in 2% bovine bile, of which 13 grew in acidified broth at pH 3.5 in acidified cysteine-containing MRS broth. Intrinsic resistance to certain antimicrobial agents (cefoxitin, metronidazole, vancomycin) was observed in most isolates, but atypical resistances to erythromycin, clindamycin, or tetracycline were also found in 5 strains. Undesirable traits such as ,-chymotrypsin or N-acetyl-,-glucosaminidase activities were not detected, but low ,-glucuronidase and moderate ,-glucosidase activities were recorded in 2 strains. Two Lactobacillus gasseri and 2 Lactobacillus paracasei selected strains inhibited several intestinal pathogens in an agar spot test, including strains of Escherichia coli, Listeria monocytogenes, Salmonella typhimurium, and Staphylococcus aureus. They also adhered to human Caco-2 and HT-29 epithelial cells in a manner comparable to Lactobacillus rhamnosus strain GG, and were unable to degrade pig gastric mucin in a plate assay. Together, these results suggest these 4 strains to be good probiotic candidates, concluding that the subtractive screening devised in this work could be a valuable tool in large-scale surveys for probiotics. [source] Effects of vancomycin, daptomycin, fosfomycin, tigecycline, and ceftriaxone on Staphylococcus epidermidis biofilmsJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 10 2009Stefan Hajdu Abstract Infection of medical implanted material is associated with considerable morbidity and costs. In the following work, we investigated the effects of vancomycin, daptomycin, fosfomycin, tigecycline, and ceftriaxone on biofilms formed by Staphylococcus epidermidis isolates causative for implant infection and catheter-associated bacteremia. Biofilms were studied using the static microtiter plate model and incubated with the antibiotics increasing the concentration from 1× to 128× the minimal inhibitory concentration (MIC) of the respective isolate tested. To quantify the reduction of the biomass, the optical density ratio (ODr) of stained biofilms and the number of growing bacteria were determined. Incubation of the staphylococcal biofilms with the antibiotics decreased the biofilm ODr (at baseline,=,1) for ceftriaxone (0.83,±,0.48) but minimally only for fosfomycin (0.96,±,0.64), daptomycin (1.05,±,0.59), tigecycline (1.18,±,0.66), and vancomycin (0.98,±,0.44) at exceedingly high concentrations of 128,×,MIC. The significant reduction of the bacterial growth was not achieved for all antibiotics, not even at the highest concentrations tested. Using higher doses of the antibiotics may be of some value in the treatment of biofilm-associated infections, although effects are seen only at clinically unachievable doses. However, to eradicate the staphylococcal biofilm, additional measures like debridement and/or removal of the implant are needed. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:1361,1365, 2009 [source] Vancomycin covalently bonded to titanium alloy prevents bacterial colonizationJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 7 2007Valentin Antoci Jr. Abstract Periprosthetic infection is a devastating consequence of implant insertion and can arise from hematogenous sources or surgical contamination. Microbes can preferentially colonize the implant surface and, by forming a biofilm, escape immune surveillance. We hypothesized that if an antibiotic can be tethered to a titanium alloy (Ti) surface, it will inhibit bacterial colonization, prevent biofilm formation, and avert late-stage infection. To test this hypothesis, a Ti rod was covalently derivatized with vancomycin. Reaction efficiencies were evaluated by colorimetric and spectrophotometric measurements. The vancomycin-modified surface was stable in aqueous solutions over extended time periods and maintained antibiotic coverage, even after press-fit insertion into a cadaverous rat femora. When evaluated using fluorescently labeled bacteria, or by direct colony counts, the surface-bound antibiotic prevented bacterial colonization in vitro after: (1) exposure to high levels of S. aureus; (2) extended incubation in physiological buffers; and (3) repeated bacterial challenges. Importantly, whereas the vancomycin-derivitized pins prevented bacterial colonization, S. aureus adhered to control pins, even in the presence of concentrations of vancomycin that exceeded the strain MIC. These results demonstrate that we have effectively engineered a stable, bactericidal Ti surface. This new surface holds great promise in terms of mitigating or preventing periprosthetic infection. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:858,866, 2007 [source] Antibiotic-containing hyaluronic acid gel as an antibacterial carrier: Usefulness of sponge and film-formed HA gel in deep infectionJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 3 2006Hiroaki Matsuno Abstract We have developed a novel bioabsorbable antibacterial carrier using hyaluronic acid (HA) gel for prevention and treatment of orthopedic infections. In this study, we investigated the in vivo antibacterial effects of two forms of this new material, an HA gel sponge and an HA gel film. A titanium cylinder was inserted into the intramedullary cavity of each rabbit femur, along with an HA gel sponge or HA gel film containing antibiotics. The HA gel sponge contained gentamycin, vancomycin, tobramycin, or minomycin. The HA gel film contained gentamycin or vancomycin. After 0, 7, and 14 days, the rabbit bone marrow was collected, and the antibacterial activity of the HA gel was determined by agar diffusion test. As a control, we used Septocoll, a commercially available antibacterial carrier. Both the HA gel sponge and HA gel film exhibited antibacterial activity. The present results indicate that HA gel containing antibiotics is a clinically useful bioabsorbable antibacterial carrier. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 24:321,326, 2006 [source] Antibiotics modulate the stimulated cytokine response to endotoxin in a human ex vivo, in vitro modelACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 9 2006S. Ziegeler Background:, Sepsis may lead to the suppression of stimulated cytokine release after Gram-negative stimuli, correlating with a fatal outcome. Treatment of sepsis includes adequate therapy with antibiotics. The aim of this study was to investigate the role of antibiotics in the modulation of the lipopolysaccharide (LPS)-stimulated cytokine response of human monocytes. Methods:, In this ex vivo, in vitro study, whole blood samples were taken from 10 healthy volunteers, stimulated with LPS in the presence or absence of various antibiotics (penicillin, amoxicillin, cefuroxime, ceftazidime, cefotaxime, piperacillin/tazobactam, imipenem/cilastatin, gentamicin, netilmicin, ciprofloxacin, vancomycin) and cultured for 24 h. Thereafter, tumor necrosis factor-, (TNF-,) and interleukin-10 (IL-10) were measured in the supernatants by enzyme-linked immunosorbent assay (ELISA). Furthermore, CD14 and HLA-DR expression on monocytes was assessed using flow cytometry. Results:, All cephalosporins decreased LPS-stimulated IL-10 release. Cefuroxime and cefotaxime also decreased the expression density of the LPS recognition molecule CD14 on monocytes. An increase in LPS-stimulated IL-10 release was observed with vancomycin. A suppression of LPS-stimulated TNF-, and IL-10 release was observed in the presence of ciprofloxacin. Conclusion:, These results indicate a modulation of the expression density of CD14 on monocytes, together with a shift from a balanced to an inflammatory cytokine release pattern, by cefuroxime and cefotaxime. Vancomycin changes the response to an anti-inflammatory release pattern. After ciprofloxacin, a profound unresponsiveness of immune-competent cells to LPS stimulation is observed. Because of the critical role of a balanced innate immune response, these data may be of importance for the selection of antibiotics in septic patients. [source] Colonization of Legionella Species in Hotel Water Systems in TurkeyJOURNAL OF TRAVEL MEDICINE, Issue 6 2007Haluk Erdogan MD Background The goal of this study was to evaluate the prevalence of Legionella species in hotel water distribution systems in Alanya, Turkey, which is an important tourism center. Methods Water and swab samples were obtained from 52 Turkish hotels from August 2003 to September 2005. Water samples were collected in 100 mL sterile containers and were concentrated by membrane filters with a pore size of 0.45 ,m. Heat treatment was used to eliminate other microorganisms from the samples, which were then spread on buffered charcoal yeast extract , agar plates and glycine, vancomycin, polymyxin, cycloheximide agar plates. Cysteine-dependent colonies were identified by latex agglutination. Results In all, 491 water and swab samples were analyzed. The results of all samples were negative for Legionella in 16 (30.8%) hotels. Legionella species (92.5% of which were Legionella pneumophila) were detected in 93 (18.9%) of the samples. The most frequently isolated species were L pneumophila serogroups 6 (63.5%) and 1 (21.5%). ConclusionsLegionella pneumophila serogroup 6 was the most common isolate detected in Turkish hotel water systems in our study. The result of Legionella urinary antigen tests, which are the diagnostic tests most often used to identify legionnaires' disease, may be negative in people infected with L pneumophila serogroup 6. We suggest that clinicians should apply the whole spectrum of laboratory methods for the detection of legionnaires' disease in patients with pneumonia of unknown origin and history of travel to Alanya, Turkey. [source] | |||||||||||||||||||||||||||||||