J Hosp Infect, 1999 Feb, 41(2), 133 - 5 Evaluation of tube coagulase and a fluorogenic substrate for rapid detection of methicillin-resistant Staphylococcus aureus from selective enrichment broth in an outbreak of EMRSA 15; Ford M et al.; We investigated the use of tube coagulase and a fluorescent substrate, N-t-BOC-val-pro-arg-7-amido-4-methylcoumarin for the rapid detection of MRSA in selective broth enrichment cultures during an outbreak . These methods were compared with direct plating of swabs and plating a selective broth enrichment culture using 200 screening swabs collected from forty patients during the investigation of an outbreak of E-MRSA 15 . Overall 66 swabs were positive for MRSA following subculture of broth enrichment culture . Direct plating detected 25 (38%) positives, tube coagulase 37 (56%), and fluorescent substrate 49 (74%) respectively, although nine of the 49 turned out to be false reactions . When detection from individual patients was analyzed, selective broth subculture identified 28 patients colonized with MRSA . Direct plating detected only 12 (43%) of these patients . The tube coagulase and fluorescence methods detected MRSA in 17 (60%) and 19 (68%) patients respectively . The tube coagulase method was found to be 100% specific for MRSA suggesting its use as a rapid method for the detection of MRSA from selective enrichment broth. J Hosp Infect, 1999 Feb, 41(2), 123 - 32 A Norwegian nosocomial outbreak of methicillin-resistant Staphylococcus aureus resistant to fusidic acid and susceptible to other antistaphylococcal agents; Andersen BM et al.; In Norway, infections caused by methicillin resistant Staphylococcus aureus (MRSA) are still uncommon . From December 1993 to January 1997, MRSA was isolated from 22 people in Oslo county; 17 patients and five carriers (healthcare workers) . A cluster of ten people (five patients and five healthcare workers) were associated with an outbreak at two hospitals in Oslo . The five patients were all admitted to the same intensive care unit (ICU) at Ulleval University Hospital between May-July 1995 (they were not transferred from abroad) and treated for acute neurological lesions . After surgery, four of them (one died) were transferred to another hospital for rehabilitation and training . The presence of MRSA was discovered in the patients and the five healthcare workers during the 10 months June 1995-March 1996 . All cluster strains showed an unusual antibiotic resistance pattern in vitro, with a relatively low degree of methicillin resistance, resistance to fusidic acid, but sensitivity to all other anti-staphylococcal agents . A clonal spread of this fusidic acid resistant MRSA was supported by strain typing using pulsed-field gel electrophoresis (PFGE), which showed that all ten cluster strains belonged to one type or its subtype. Vojnosanit Pregl, 1998 Nov-Dec, 55(6), 611 - 5 {Efficacy of continuous ambulatory peritoneal dialysis in treatment of children with end-stage renal insufficiency}; Sahapozova E et al.; Three children (2 girls and 1 boy) with end-stage renal failure were put in program of continuous ambulatory peritoneal dialysis in the period of 2.5 years (January 1995-September 1997) . The age of the children at the treatment onset was 5-12 years . One of three children died due to cardiovascular failure after six-month treatment . Two out of three children had a total of 8 episodes of peritonitis in the period of 37 months during the treatment with peritoneal dialysis . The incidence of peritonitis occurrence in our patients was one episode in 4 patients/months . Most frequent cause for peritonitis occurrence was Staphylococcus aureus in 50% of isolated bacteria . Obtained results in peritoneal equilibration test revealed that the transport and ultrafiltration rate of peritoneal membrane decreased after recurrent peritonitis episodes. J Antimicrob Chemother, 1998 Dec, 42(6), 807 - 10 The effect of reserpine, an inhibitor of multidrug efflux pumps, on the in-vitro activities of ciprofloxacin, sparfloxacin and moxifloxacin against clinical isolates of Staphylococcus aureus; Schmitz FJ et al.; In Staphylococcus aureus, in addition to mutations in the grl and gyr gene loci, multidrug efflux pumps like NorA contribute to decreased fluoroquinolone susceptibility . Efflux pumps can be inhibited by the plant alkaloid reserpine, which, at 20 mg/L, reduced sparfloxacin, moxifloxacin and ciprofloxacin IC50s and MICs by up to four-fold in 11, 21 and 48 of the 102 unrelated clinical isolates tested, respectively . The effect was less pronounced with the hydrophobic drugs sparfloxacin and moxifloxacin than with the hydrophilic drug ciprofloxacin and was stable in all 25 clonally related isolates tested. J Orthop Trauma, 1999 Feb, 13(2), 102 - 6 Efficacy of gentamycin-impregnated resorbable hydroxyapatite cement in treating osteomyelitis in a rat model; Solberg BD et al.; OBJECTIVE: To test the effectiveness of a self-setting hydroxyapatite cement (HAC) as a carrier of gentamycin for the treatment of chronic osteomyelitis in a rat model by using a void-fill placement technique . DESIGN: Osteomyelitis of the tibia was created with Staphylococcus aureus (ATCC 49230) in sixty retired female breeder Sprague-Dawley rats by using the model by Korkusuz et al . (J Bone Joint Surg 1993;75B:111-114) . At seven weeks after infection, all animals demonstrated clinical and radiographic signs of osteomyelitis and were debrided and divided into four treatment groups: A, debridement only; B, debridement and daily intraperitoneal gentamycin (0.2 milligram per kilogram per day); C, debridement and gentamycin-impregnated HAC in a void-fill model (1.0 milligram per kilogram of gentamycin); and D, debridement and gentamycin-impregnated polymethylmethacrylate (PMMA) beads (1.0 milligram per kilogram of gentamycin) . Tibiae were harvested at zero weeks (control, n = 6), three weeks (n = 3 per group), five weeks (n = 4 per group), and seven weeks (n = 4 per group) and analyzed with quantitative bacteriologic analysis . OUTCOME MEASUREMENT: Qualitative bacteriologic analysis was performed by using serial dilution plating of homogenized tissue samples on standard soy trypticase agar plates . Reexamination by phage typing was performed to exclude contamination . RESULTS: The quantitative counts for Groups C (HAC) and D (PMMA) were significantly less (p < 0.003) than those for Group A (debridement alone) or Group B (intraperitoneal gentamycin) at all time points after time zero . There was no difference between Groups C and D at any time point . CONCLUSION: HAC is an effective adjuvant in treating chronic osteomyelitis in a rat model when using a void-fill placement technique. J Orthop Trauma, 1999 Feb, 13(2), 98 - 101 Use of a tobramycin-impregnated polymethylmethacrylate pin sleeve for the prevention of pin-tract infection in goats; Voos K et al.; OBJECTIVE: To test the hypothesis that antibiotic-laden polymethylmethacrylate (PMMA) pin sleeves prevent infection around skeletal external fixation pins . DESIGN: An experimental study using an animal model was conducted . ANIMALS: In each of five goats, three four-millimeter half-pins were placed in the left and right iliac crests, for a total of thirty half-pins . The pins were infected with one milliliter of broth containing 7.6 x 10(5) colony-forming units per milliliter of Staphylococcus aureus (ATCC 25923) . INTERVENTION: The pins in the right iliac crest were treated with the tobramycin-impregnated pin sleeves, and the pins in the left iliac crest (control) were left untreated . RESULTS: The results showed clinical evidence of infection (i.e., looseness and gross pus) and heavy bacterial growth (average 6.8 x 10(10) colony-forming units per milliliter) for the untreated pins, but no clinical evidence of infection and no bacterial growth at forty-eight hours for the treated pins . CONCLUSION: The present results indicate that the use of the antibiotic-impregnated PMMA pin sleeve can prevent the development of pin-tract infection and appears to prevent colonization of the external fixation pins. APMIS, 1998 Dec, 106(12), 1157 - 64 Secretion of IL-6, IL-8 and G-CSF by human endothelial cells in vitro in response to Staphylococcus aureus and staphylococcal exotoxins; Soderquist B et al.; The capacity of endothelial cells to produce and release cytokines (IL-6, IL-8 and G-CSF) in response to exposure to Staphylococcus aureus strains or staphylococcal exotoxins (alpha-toxin, enterotoxin A and TSST-1) was investigated . An endothelial cell culture model of human umbilical vein endothelial cells (HUVEC) was used . Five out of ten clinical isolates of S . aureus were found to induce cytokine production and release from endothelial cells . Four of the five isolates that induce cytokine release produced enterotoxin A, B, C, D and/or TSST-1, compared with two of those that did not induce release . Purified staphylococcal exotoxins (1 pg/ml-1 microg/ml) did not act as primary stimuli and induced no detectable cytokine secretion . When endothelial cells were prestimulated with IL-1beta or TNF alpha at a concentration of 1 ng/ml for 2 h, IL-1beta served as a potent primary stimulus for IL-6, IL-8 and G-CSF production, whereas TNF alpha did not induce any significant cytokine release during the subsequent 24 h . A further increase in IL-6 and G-CSF release, but not of IL-8, was observed when IL-1beta prestimulated cells were exposed to alpha-toxin or TSST-1 . However, to potentiate cytokine production (IL-6 and IL-8) by SEA, both IL-1beta and the toxin had to be present simultaneously . Our data show that S . aureus, but not staphylococcal exotoxins, have the capacity to act as primary stimuli of endothelial cells and induce production and release of cytokines . IL-1beta may prime HUVEC to release IL-6, IL-8 and G-CSF prior to subsequent stimulation with staphylococcal exotoxins. Eur J Clin Microbiol Infect Dis, 1998 Dec, 17(12), 877 - 9 High-level mupirocin resistance among Spanish methicillin-resistant Staphylococcus aureus; Alarcon T et al.; Twelve strains of methicillin-resistant Staphylococcus aureus with high-level resistance to mupirocin were studied . The MIC of methicillin was 16 to 128 mg/l and the MIC of mupirocin > or = 512 mg/l . All of the isolates carried a plasmid of about 30 MDa, and one strain lost resistance to mupirocin when the plasmid was cured . Three different resistance patterns were found: six strains were resistant to ciprofloxacin, kanamycin, and 10 mg/l of cadmium sulfate; two strains were resistant to these agents as well as to gentamicin, erythromycin, clindamycin, mercury chloride, and ethidium bromide; and four strains were resistant to the previously named agents as well as to rifampicin and tetracycline . The use of this valuable topical antibiotic, especially in long-term-care facilities, should be monitored to avoid dissemination of resistance. Proc Natl Acad Sci U S A, 1999 Mar 2, 96(5), 2279 - 84 Crossreactive recognition of viral, self, and bacterial peptide ligands by human class I-restricted cytotoxic T lymphocyte clonotypes: implications for molecular mimicry in autoimmune disease; Misko IS et al.; The immunodominant, CD8(+) cytotoxic T lymphocyte (CTL) response to the HLA-B8-restricted peptide, RAKFKQLL, located in the Epstein-Barr virus immediate-early antigen, BZLF1, is characterized by a diverse T cell receptor (TCR) repertoire . Here, we show that this diversity can be partitioned on the basis of crossreactive cytotoxicity patterns involving the recognition of a self peptide-RSKFRQIV-located in a serine/threonine kinase and a bacterial peptide-RRKYKQII-located in Staphylococcus aureus replication initiation protein . Thus CTL clones that recognized the viral, self, and bacterial peptides expressed a highly restricted alphabeta TCR phenotype . The CTL clones that recognized viral and self peptides were more oligoclonal, whereas clones that strictly recognized the viral peptide displayed a diverse TCR profile . Interestingly, the self and bacterial peptides equally were substantially less effective than the cognate viral peptide in sensitizing target cell lysis, and also resulted only in a weak reactivation of memory CTLs in limiting dilution assays, whereas the cognate peptide was highly immunogenic . The described crossreactions show that human antiviral, CD8(+) CTL responses can be shaped by peptide ligands derived from autoantigens and environmental bacterial antigens, thereby providing a firm structural basis for molecular mimicry involving class I-restricted CTLs in the pathogenesis of autoimmune disease. Int J Food Microbiol, 1999 Jan 12, 46(1), 45 - 55 A mathematical model for bacterial inactivation; Xiong R et al.; The first order kinetic model, the Buchanan model and Cerf's model, can model a linear survival curve, a survival curve with a shoulder and a survival curve with a tailing, respectively . However, they are not suitable for fitting a sigmoidal survival curve . The three models were integrated into a new model that was capable of fitting the four most commonly observed survival curves: linear curves, curves with a shoulder, curves with a tailing (biphasic curves) and sigmoidal curves . The new model was compared with the Whiting-Buchanan model using the survival curves of Staphylococcus aureus . The goodness-of-fit of the proposed model is practically as good as that of the Whiting-Buchanan model . Compared with the Whiting-Buchanan model, the proposed model has a more mechanistic background . Since for non-linear survival curves, such as biphasic and sigmoidal curves, the t(m-D) value (the time required for an m-log-cycle reduction of microorganisms under a given condition) cannot be estimated accurately by the existing or traditional method, a new method is also proposed to predict accurately the t(m-D) value for non-linear survival curves. Ann Intern Med, 1999 Feb 2, 130(3), 221 - 5 Nasal carriage of and infection with Staphylococcus aureus in HIV-infected patients; Nguyen MH et al.; BACKGROUND: Staphylococcus aureus is a common cause of serious infection in patients infected with HIV . OBJECTIVES: To evaluate risk factors for and quantitative effect of S . aureus infection in HIV-infected patients, with special attention to nasal carriage . DESIGN: Prospective, multihospital cohort study . SETTING: Three tertiary care Veterans Affairs Medical Centers . PARTICIPANTS: 231 ambulatory HIV-infected patients . RESULTS: Thirty-four percent of patients were nasal carriers of S . aureus . Of these patients, 38% were persistent carriers and 62% were intermittent carriers . Twenty-one episodes of infection occurred in 13 patients: Ten were bacteremias (including 2 cases of endocarditis), 1 was pneumonia, and 10 were cutaneous or subcutaneous infections . Seventeen (85%) of these episodes occurred in patients with CD4 counts less than 100 cells/mm3 . Recurrent infections occurred in 3 of 7 patients who survived an initial S . aureus infection . The mortality rate was higher among patients with S . aureus infection than among those without infection (P = 0.03) . Factors significantly associated with S . aureus infection were nasal carriage, presence of a vascular catheter, low CD4 count, and neutropenia . Molecular strain typing indicated that for 6 of 7 infected patients, the strain of S . aureus isolated from the infected sites was the same as that previously cultured from the nares . CONCLUSION: Nasal carriage is an important risk factor for S . aureus infection in HIV-infected patients . Controlled studies are indicated to determine whether eradication of nasal carriage in a selected subset of patients (for example, those with a low CD4 cell count) might prevent invasive S . aureus infection in patients with HIV infection. Biophys J, 1999 Mar, 76(3), 1469 - 79 Localization and environment of tryptophans in soluble and membrane-bound states of a pore-forming toxin from Staphylococcus aureus; Raja SM et al.; The location and environment of tryptophans in the soluble and membrane-bound forms of Staphylococcus aureus alpha-toxin were monitored using intrinsic tryptophan fluorescence . Fluorescence quenching of the toxin monomer in solution indicated varying degrees of tryptophan burial within the protein interior . N-Bromosuccinimide readily abolished 80% of the fluorescence in solution . The residual fluorescence of the modified toxin showed a blue-shifted emission maximum, a longer fluorescence lifetime as compared to the unmodified and membrane-bound alpha-toxin, and a 5- to 6-nm red edge excitation shift, all indicating a restricted tryptophan environment and deeply buried tryptophans . In the membrane-bound form, the fluorescence of alpha-toxin was quenched by iodide, indicating a conformational change leading to exposure of some tryptophans . A shorter average lifetime of tryptophans in the membrane-bound alpha-toxin as compared to the native toxin supported the conclusions based on iodide quenching of the membrane-bound toxin . Fluorescence quenching of membrane-bound alpha-toxin using brominated and spin-labeled fatty acids showed no quenching of fluorescence using brominated lipids . However, significant quenching was observed using 5- and 12-doxyl stearic acids . An average depth calculation using the parallax method indicated that the doxyl-quenchable tryptophans are located at an average depth of 10 A from the center of the bilayer close to the membrane interface . This was found to be in striking agreement with the recently described structure of the membrane-bound form of alpha-toxin. Antimicrob Agents Chemother, 1999 Mar, 43(3), 717 - 21 Evaluation of bactericidal activities of LY333328, vancomycin, teicoplanin, ampicillin-sulbactam, trovafloxacin, and RP59500 alone or in combination with rifampin or gentamicin against different strains of vancomycin-intermediate Staphylococcus aureus by time-kill curve methods; Hershberger E et al.; This in vitro study evaluated the activities of vancomycin, LY333328, and teicoplanin alone and in combination with gentamicin, rifampin, and RP59500 against Staphylococcus aureus isolates with intermediate susceptibilities to vancomycin . Ampicillin-sulbactam and trovafloxacin were also evaluated . LY333328 and ampicillin-sulbactam resulted in bactericidal activity against all isolates . The combination of gentamicin with glycopeptides showed synergistic activity, while rifampin had no added benefit. Antimicrob Agents Chemother, 1999 Mar, 43(3), 667 - 71 Comparison of efficacies of oral levofloxacin and oral ciprofloxacin in a rabbit model of a staphylococcal abscess; Fernandez J et al.; Oral levofloxacin was compared to oral ciprofloxacin in a Staphylococcus aureus subcutaneous abscess model in rabbits . Rabbits were surgically prepared with subcutaneous wiffle balls (43 mm in diameter) and allowed to recover for 4 to 6 weeks . Rabbits were infected by direct injection into the capsule with S . aureus ATCC 29213 (5 x 10(5) CFU) and were allowed to remain infected for 8 days before the initiation of anti-infective treatment . Efficacy was determined by assessing the bacterial load within the capsule over a 10-day treatment period . In single-dose pharmacokinetic studies in infected rabbits, similar area under the concentration-time curve/MIC ratios were obtained in the plasma and abscess fluid for levofloxacin at 45 mg/kg of body weight and ciprofloxacin at 200 mg/kg of body weight . Similar efficacies were seen with levofloxacin at 45 mg/kg/day and ciprofloxacin 400 mg/kg/day by day 10 . In this model, levofloxacin was significantly more efficacious than ciprofloxacin (P < 0.01). Antimicrob Agents Chemother, 1999 Mar, 43(3), 498 - 502 Prediction of the effects of inoculum size on the antimicrobial action of trovafloxacin and ciprofloxacin against Staphylococcus aureus and Escherichia coli in an in vitro dynamic model; Firsov AA et al.; The effect of inoculum size (N0) on antimicrobial action has not been extensively studied in in vitro dynamic models . To investigate this effect and its predictability, killing and regrowth kinetics of Staphylococcus aureus and Escherichia coli exposed to monoexponentially decreasing concentrations of trovafloxacin (as a single dose) and ciprofloxacin (two doses at a 12-h interval) were compared at N0 = 10(6) and 10(9) CFU/ml (S . aureus) and at N0 = 10(6), 10(7), and 10(9) CFU/ml (E . coli) . A series of pharmacokinetic profiles of trovafloxacin and ciprofloxacin with respective half-lives of 9.2 and 4 h were simulated at different ratios of area under the concentration-time curve (AUC) to MIC (in {micrograms x hours/milliliter}/{micrograms/milliliter}): 58 to 466 with trovafloxacin and 116 to 932 with ciprofloxacin for S . aureus and 58 to 233 and 116 to 466 for E . coli, respectively . Although the effect of N0 was more pronounced for E . coli than for S . aureus, only a minor increase in minimum numbers of surviving bacteria and an almost negligible delay in their regrowth were associated with an increase of the N0 for both organisms . The N0-induced reductions of the intensity of the antimicrobial effect (IE, area between control growth and the killing-regrowth curves) were also relatively small . However, the N0 effect could not be eliminated either by simple shifting of the time-kill curves obtained at higher N0s by the difference between the higher and lowest N0 or by operating with IEs determined within the N0-adopted upper limits of bacterial numbers (IE's) . By using multivariate correlation and regression analyses, linear relationships between IE and log AUC/MIC and log N0 related to the respective mean values {(log AUC/MIC)average and (log N0)average} were established for both trovafloxacin and ciprofloxacin against each of the strains (r2 = 0.97 to 0.99) . The antimicrobial effect may be accurately predicted at a given AUC/MIC of trovafloxacin or ciprofloxacin and at a given N0 based on the relationship IE = a + b {(log AUC/MIC)/(log AUC/MIC)average} - c {(log N0)/(log N0)average} . Moreover, the relative impacts of AUC/MIC and N0 on IE may be evaluated . Since the c/b ratios for trovafloxacin and ciprofloxacin against E . coli were much lower (0.3 to 0.4) than that for ampicillin-sulbactam as examined previously (1.9), the inoculum effect with the quinolones may be much less pronounced than with the beta-lactams . The described approach to the analysis of the inoculum effect in in vitro dynamic models might be useful in studies with other antibiotic classes. J Antibiot (Tokyo), 1998 Dec, 51(12), 1087 - 92 Diperamycin, a new antimicrobial antibiotic produced by Streptomyces griseoaurantiacus MK393-AF2 . I . Taxonomy, fermentation, isolation, physico-chemical properties and biological activities; Matsumoto N et al.; Antibacterial antibiotics, diperamycin (1) was produced in the culture broth of Streptomyces griseoaurantiacus MK393-AF2 . Various spectroscopic analyses of 1 suggested that 1 belonged to a member of cyclic hexadepsipeptide antibiotic . Antibiotic 1 had potent inhibitory activity against various Gram-positive bacteria including Enterococcus seriolicida and methicillin-resistant Staphylococcus aureus. J Ocul Pharmacol Ther, 1999 Feb, 15(1), 91 - 6 High dose intramuscular methylprednisolone in experimental Staphylococcus aureus endophthalmitis; Yoshizumi MO et al.; We attempted to determine whether treatment using intramuscular methylprednisolone plus intravitreal vancomycin decreased ocular inflammation and preserved retinal function better in experimental Staphylococcus aureus (S . aureus) endophthalmitis than treatment with intravitreal vancomycin alone . Sixteen rabbits received intravitreal inoculations in both eyes with S . aureus and the rabbits were divided into two groups (group I and group II) of eight rabbits each . Group I rabbits were treated with one injection of intravitreal vancomycin in each eye at either 24, 36, 48 or 72 hours after bacterial inoculation followed by seven consecutive days of high dose intramuscular methylprednisolone (30 mg/kg per day) . Group II rabbits were treated with only one intravitreal injection of vancomycin in each eye at equivalent time intervals as in Group I . Clinical evaluations of ocular inflammation were performed by slit-lamp biomicroscopy and indirect ophthalmoscopy . Electroretinography (ERG) was performed eight days after bacterial inoculation to assess retinal function in all eyes . The combination of intramuscular methylprednisolone and intravitreal vancomycin resulted in a degree of ocular inflammation equal to eyes treated with intravitreal vancomycin alone at all treatment intervals . ERG responses were not significantly different in either group . A single intravitreal injection of vancomycin plus daily intramuscular methylprednisolone for seven days were found neither to decrease ocular inflammation nor preserve retinal function better than a single intravitreal injection of vancomycin in our experimental model of S . aureus endophthalmitis. Dermatol Surg, 1999 Feb, 25(2), 89 - 93 The evaluation of a cadexomer iodine wound dressing on methicillin resistant Staphylococcus aureus (MRSA) in acute wounds; Mertz PM et al.; BACKGROUND: Many bacteria have become resistant to commonly-used antibiotics . OBJECTIVE: The purpose of this study was to examine the effect of a cadexomer iodine wound dressing on methicillin resistant Staphylococcus aureus (MRSA) . METHOD: Partial thickness wounds were made on the backs of three pigs and inoculated with a known amount of MRSA . Wounds were treated with either cadexomer iodine dressing or vehicle dressing (without iodine), or they were left untreated . Three wounds from each treatment group per animal were cultured using quantitative scrub techniques after 24, 48, or 72 hours of treatment . CONCLUSIONS: The cadexomer iodine dressing significantly reduced MRSA and total bacteria in the wounds as compared to both the no treatment control and vehicle . No significant differences were observed in the number of bacteria recovered between the no treatment control and cadexomer (vehicle) treated wounds . Cadexomer iodine may be an effective agent for preventing proliferation of MRSA in wounds. Microbiol Immunol, 1998, 42(12), 829 - 36 New evidence that the Tyr-157 and Tyr-159 residues of staphylococcal exfoliative toxin B are essential for its toxicity; Sakurai S et al.; To determine the active site of exfoliative toxin B (sETB) of Staphylococcus aureus, the etb gene was cloned from an S . aureus SU strain obtained from a patient with impetigo . We prepared a frame shift mutant protein from a recombinant plasmid with a BglII linker inserted into the Tyr-155 codon of the ETB gene (pETB/BglIIL) . The recombinant mutant protein (ETB/BglIIL) obtained from Escherichia coli containing pETB/BgIIIL showed no toxicity in neonatal mice and no agglutination activity . The 20-kDa ETB/BglIIL contained 185 amino acid residues . Site-directed mutagenesis was used to introduce mutations at either Tyr-155, Tyr-157, Tyr-159, or Tyr-162 . Substitution of any of the Tyr residues decreased exfoliative activity compared with that of native sETB (4,000 EU/ml) . Substitution of Tyr-155 with a Phe (ETBYN155) decreased activity 5-fold (800 EU/ml) . Substitution of Tyr-157 with Leu (ETB/Y157) decreased activity 80-fold (50 EU/ml) and decreased agglutination titer 5-fold compared with that of native sETB (400,000) . Substitution of Tyr-159 with Leu (ETB/Y159)decreased activity 4-fold (1,000 EU/ml) . When both Tyr-157 and Tyr-159 were mutated (ETB/Y157-159), both toxicity and antigenicity were completely lost . On an immunodiffusion test, ETBNY157 showed a faint precipitation line, but ETB/BglIIL and ETB/Y157-159 had no activity, showing that the Tyr-157 and Tyr-159 residues are essential for the toxicity and antigenicity of ETB. Kyobu Geka, 1999 Feb, 52(2), 163 - 7 {Curative report of two cases with MRSA mediastinitis after cardiovascular surgery, treated by new irrigation technique (intermittent mass-irrigation technique)}; Matsumura G et al.; We experienced a 42-year-old patient who underwent aortic valve replacement and a 63-year-old patient who underwent coronary artery bypass grafting with mediastinitis caused by methicillin-resistant Staphylococcus aureus (MRSA) . They were successfully treated with the intermittent mass-irrigation technique . The irrigation device consistent of a irrigation tube which placed in upper half of mediastinum and three suction tubes which placed in lower half . We dripped the wash composed of 0.03-0.05% of Povidone-Iodine with 1,000 ml of physiological saline, for 3 to 5 times a day by condition . After each wash, we cross clamped the drainage tubes and filled mediastinum with 0.5 grams of vancomycin hydrochloride dissolved in 100 ml of physiological saline, dripped from irrigation tube, for 30 minutes . After 9-day irrigation in the former case and 16-day irrigation in the latter case, the culture of drainage turned negative . We presumed that this new method is effective for mediastinitis after cardiovascular surgery. Trends Microbiol, 1998 Dec, 6(12), 484 - 8 Surface protein adhesins of Staphylococcus aureus; Foster TJ et al.; Staphylococcus aureus can colonize the host to initiate infection by adhering to components of the extracellular matrix . Adherence is mediated by surface protein adhesins (MSCRAMMs) . Ligand binding by these fibronectin-, fibrinogen- and collagen-binding proteins occurs by distinct mechanisms that are being investigated at the molecular level. Rinsho Biseibutshu Jinsoku Shindan Kenkyukai Shi, 1998 Nov 25, 9(1), 27 - 32 Studies on Methicillin-Resistant Staphylococcus aureus Bacteremia Due to Laboratory Medical Analysis; Furuta I I et al.; We encountered 64 patients with methicillin-resistant Staphylococcus aureus (MRSA) bacteremia between April 1993 and March 1994 . Mean patient age was 54 years . There were 46 males and 18 females . Underlying diseases mainly consisted of traffic accident (10 patients), valvular heart disease (5 patients), chronic renal failure (5 patients), leukemia (5 patients), pneumonia (3 patients), and malignant lymphoma (3 patients) . The common clinical laboratory findings of MRSA bacteremia included decreses in total protein, albumin and hemoglobin as well as increases in white blood cells (neutrophils) and C reactive protein . In particular, an increase in C reactive protein by 10 mg/dl or more may be useful for diagnosing bacteremia . Laboratory findings were compared between surviving and non-surviving patients . There were significant differences in albumin, cholesterol, bilirubin, creatinine, and CRP . In 18 patients (28.1%), bacteremia was caused by infection due to contamination of central venous catheters . Since medical treatment with intra-vascular devices may cause bacteremia, sufficient caution is needed. Epidemiol Infect, 1998 Dec, 121(3), 507 - 14 Epidemiological characterization of methicillin-resistant Staphylococcus aureus isolated in the North West of England by protein A (spa) and coagulase (coa) gene polymorphisms; Walker J et al.; In a comparative study, isolates of methicillin-resistant Staphylococcus aureus (MRSA) with known pulsed-field gel electrophoresis (PFGE) and bacteriophage type were analysed by polymerase chain reaction (PCR) and restriction fragment length polymorphisms (RFLP) for additional discriminatory subtyping information . PFGE was previously performed using standardized, commercially available kits and pre-programmed software . Isolates were examined for coagulase (coa) and protein A (spa) gene polymorphisms following PCR amplification of the coa hypervariable and spa repeat regions . Coa gene RFLPs produced a total of 38 distinct combined patterns after digestion with HaeIII and AluI and identified the predominant epidemic (EMRSA) types 15 and 16 . A unique HaeIII restriction site was identified by RFLP and sequence analysis in the coa gene for EMRSA 15 but not EMRSA 16 . The spa gene PCR yielded a total of 14 different profiles ranging from 3-18 repeats with the 2 predominant EMRSA types falling into 2 distinct groups . PCR detection of coa and spa polymorphisms offer a rapid preliminary strain identification and discriminatory subtyping information for surveillance of MRSA. J Food Prot, 1999 Feb, 62(2), 194 - 7 Fate of gram-positive bacteria in reconditioned, pork-processing plant water; Palumbo SA et al.; This study investigated the responses of Enterococcus faecium (ATCC 19433), Staphylococcus aureus (196E), and Listeria monocytogenes Scott A in water from a local meat-processing plant . Each bacterium was added to a starting count of 3 log10 CFU/ml and held from 5 to 28 degrees C . At intervals (0, 2, 7, 14, and 21 days), aliquots were plated on appropriate selective agars . In contrast to the gram-negative bacteria studied previously and which grew, the three gram-positive bacteria survived with some slight increase in number in only nonchlorinated, reconditioned water, either filtered (0.22 microm pore size) or nonfiltered . The presence of chlorine in either potable or reconditioned water contributed to the rapid decline in viable counts for all three bacteria . These results further emphasize the importance of residual chlorine in preventing the growth of these gram-positive bacteria in potable and reconditioned waters. Biomaterials, 1999 Feb, 20(3), 229 - 32 Resistance of antibiotic-bonded gelatin-coated polymer meshes to Staphylococcus aureus in a rabbit subcutaneous pouch model; Goeau-Brissonniere O et al.; This study examines the efficacy of the bonding of rifampicin, vancomycin or gentamicin to gelatin-coated knitted polymer meshes to prevent perioperative infection . Antibiotic bonding was obtained by soaking the meshes for 15 min in a solution containing 20 mg ml(-1) of rifampicin or 10 mg ml(-1) of vancomycin or gentamicin . A polymer mesh was implanted in a subcutaneous pouch in 16 rabbits: four received a rifampicin-soaked mesh, four received a vancomycin-soaked mesh, four received a gentamicin-soaked mesh, and four received an untreated mesh (control group) . At the time of implantation, all the meshes were contaminated locally with 10(8) colony forming units of Staphylococcus aureus . Meshes were harvested one week later and submitted to bacterial counts . At the time of explantation, none of the antibiotic-soaked meshes were infected, whereas all the untreated meshes were infected . These results show that antibiotic soaking evidently prevents perioperative infection of gelatin-coated knitted polymer meshes in this model. Clin Infect Dis, 1999 Jan, 28(1), 106 - 14 Infective endocarditis due to Staphylococcus aureus: 59 prospectively identified cases with follow-up; Fowler VG Jr et al.; Fifty-nine consecutive patients with definite Staphylococcus aureus infective endocarditis (IE) by the Duke criteria were prospectively identified at our hospital over a 3-year period . Twenty-seven (45.8%) of the 59 patients had hospital-acquired S . aureus bacteremia . The presumed source of infection was an intravascular device in 50.8% of patients . Transthoracic echocardiography (TTE) revealed evidence of IE in 20 patients (33.9%), whereas transesophageal echocardiography (TEE) revealed evidence of IE in 48 patients (81.4%) . The outcome for patients was strongly associated with echocardiographic findings: 13 (68.4%) of 19 patients with vegetations visualized by TTE had an embolic event or died of their infection vs . five (16.7%) of 30 patients whose vegetations were visualized only by TEE (P < .01) . Most patients with S . aureus IE developed their infection as a consequence of a nosocomial or intravascular device-related infection . TEE established the diagnosis of S . aureus IE in many instances when TTE was nondiagnostic . Visualization of vegetations by TTE may provide prognostic information for patients with S . aureus IE. Ned Tijdschr Geneeskd, 1998 Nov 28, 142(48), 2630 - 3 {The spread of a 'Dutch' methicillin-resistant Staphylococcus aureus strain}; Schneeberger PM et al.; Following isolation of a methicillin-resistant Staphylococcus aureus (MRSA) in a patient subjected to amputation below the knee because of a vasculopathy, further investigations were carried out . Nose, throat and wound cultures were taken from staff and patients who had had contact with the index patient . After taking inventory cultures and cleansing of the two wards involved, these wards were quarantined . The bacterial strain was characterized using microbiological standard methods . The MRSA was encountered in a total of nine patients and two nurses . An infection due to this MRSA was found in two patients and one nurse . Eradication in the hospital was successful . MRSA with the same phage type was found in one nurse and one patient in two nearly hospitals and in one patient in a nearby city . Anamnestically, there had been no contact between them . Tracing this sort of outbreak in time is not possible with the current preventive MRSA policy because there are no demonstrable risk groups for a MRSA occurring in the Netherlands . Routine checking for MRSA carriership among nursing personnel and long-staying surgical patients is a possibility to detect spread of this MRSA . It appears advisable to take restrictive measures even against this S . aureus with restricted resistance, because neither penicillins nor cephalosporins are efficacious . In general, more attention should be given to prevention of nosocomial transmission of S . aureus. Infection, 1999 Jan-Feb, 27(1), 28 - 33 Subverting bacterial resistance using high dose, low solubility antibiotics in fibrin; Woolverton CJ et al.; Antibiotics (ABs) delivered from fibrin were evaluated for control of multi-drug resistant (MDR) Staphylococcus aureus . ABs having low aqueous solubility (< or = 1 mg/ml) were encapsulated by fibrin (composed of fibrinogen, thrombin, Factor XIIIa and calcium chloride) and examined . Electron microscopy revealed fibrin-caged, tetracycline crystals that were 0.26 to 2.8 microns in size and bound within the reticular matrix . Antibiograms documented that S . aureus ATCC 27659 was resistant to erythromycin (ERY), penicillin G (PEN), streptomycin (STR), sulfamethoxazole-trimethoprim (SXT) and tetracycline (TET) . However, low solubility formulations of STR (10 mg/ml) or SXT (0.5 mg/ml), delivered from fibrin and evaluated by the agar disk diffusion assay, produced zones of growth inhibition after 18-24 h at 37 degrees C in vitro, indicating renewed susceptibility of S . aureus ATCC 27659 to these ABs . ERY, PEN and TET were unable to overcome resistance at concentrations up to 10 mg/ml . In vivo, intraperitoneal (i.p.) injection of 150 mg/kg STR delivered from fibrin resulted in 100% survival of rats with MDR S . aureus peritonitis as compared with control rats receiving i.p . STR (150 mg/kg) in 0.9% saline . The results demonstrate that some low solubility ABs delivered from fibrin are efficacious in controlling infection mediated by MDR S . aureus. Infect Immun, 1999 Mar, 67(3), 1331 - 7 Hyperproduction of alpha-hemolysin in a sigB mutant is associated with elevated SarA expression in Staphylococcus aureus; Cheung AL et al.; To evaluate the role of SigB in modulating the expression of virulence determinants in Staphylococcus aureus, we constructed a sigB mutant of RN6390, a prototypic S . aureus strain . The mutation in the sigB gene was confirmed by the absence of the SigB protein in the mutant on an immunoblot as well as the failure of the mutant to activate sigmaB-dependent promoters (e.g., the sarC promoter) of S . aureus . Phenotypic analysis indicated that both alpha-hemolysin level and fibrinogen-binding capacity were up-regulated in the mutant strain compared with the parental strain . The increase in fibrinogen-binding capacity correlated with enhanced expression of clumping factor and coagulase on immunoblots . The effect of the sigB mutation on the enhanced expression of the alpha-hemolysin gene (hla) was primarily transcriptional . Upon complementation with a plasmid containing the sigB gene, hla expression returned to near parental levels in the mutant . Detailed immunoblot analysis as well as a competitive enzyme-linked immunosorbent assay of the cell extract of the sigB mutant with anti-SarA monoclonal antibody 1D1 revealed that the expression of SarA was higher in the mutant than in the parental control . Despite an elevated SarA level, the transcription of RNAII and RNAIII of the agr locus remained unaltered in the sigB mutant . Because of a lack of perturbation in agr, we hypothesize that inactivation of sigB leads to increased expression of SarA which, in turn, modulates target genes via an agr-independent but SarA-dependent pathway. Infect Immun, 1999 Mar, 67(3), 1045 - 9 Alpha-toxin and gamma-toxin jointly promote Staphylococcus aureus virulence in murine septic arthritis; Nilsson IM et al.; Septic arthritis is a common and feared complication of staphylococcal infections . Staphylococcus aureus produces a number of potential virulence factors including certain adhesins and enterotoxins . In this study we have assessed the roles of cytolytic toxins in the development of septic arthritis by inoculating mice with S . aureus wild-type strain 8325-4 or isogenic mutants differing in the expression of alpha-, beta-, and gamma-toxin production patterns . Mice inoculated with either an alpha- or beta-toxin mutant showed degrees of inflammation, joint damage, and weight decrease similar to wild-type-inoculated mice . In contrast, mice inoculated with either double (alpha- and gamma-toxin-deficient)- or triple (alpha-, beta-, and gamma-toxin-deficient)-mutant S . aureus strains showed lower frequency and severity of arthritis, measured both clinically and histologically, than mice inoculated with the wild-type strain . We conclude that simultaneous production of alpha- and gamma-toxin is a virulence factor in S . aureus arthritis. Am J Gastroenterol, 1999 Feb, 94(2), 391 - 7 A reassessment of splenic hypofunction in celiac disease; Corazza GR et al.; OBJECTIVES: Because there is controversy regarding the prevalence, familial occurrence, and possible factors inducing splenic hypofunction in celiac disease, we have reassessed them in a large series of untreated patients and their first-degree relatives . METHODS: Pitted red cell counting was used to measure splenic function and the effect that age at diagnosis has on it, while severity of intestinal lesions and nutritional status were estimated by multiple linear regression analysis . Moreover, serum tuftsin activity was assayed by measuring its ability to stimulate phagocytosis of opsonized Staphylococcus aureus . RESULTS: We found that 32.8% of untreated celiacs and none of their relatives had pitted red cell values in the range of splenic hypofunction (>4%) . Only age at diagnosis, but not the other two covariates, was significantly associated with the degree of splenic hypofunction . Tuftsin activity was depressed in celiac disease and this reduction was significantly greater in hyposplenic patients . CONCLUSIONS: In celiac disease the prevalence of splenic hypofunction is lower than formerly believed . The duration of preexposure to gluten is a crucial factor for the prevalence and severity of this complication that does not affect celiac relatives . In celiac disease splenic hypofunction is accompanied by a reduced phagocyte activity linked to the decreased release of tuftsin. J Immunol Methods, 1999 Jan 1, 222(1-2), 171 - 82 General expression vectors for production of hydrophobically tagged immunogens for direct iscom incorporation; Andersson C et al.; A new general strategy for the production of recombinant protein immunogens has been investigated . The rationale involves the production of a recombinant immunogen as fused to a composite tag comprising one domain suitable for affinity purification and a hydrophobic tag designed for direct incorporation through hydrophobic interaction of the affinity-purified immunogen into an adjuvant system, in this case immunostimulating complexes (iscoms) . Three different hydrophobic tags were evaluated: (i) a tag denoted IW containing stretches of hydrophobic isoleucine (I) and tryptophan (W) residues; (ii) a tag denoted MI consisting of the transmembrane region of hemagglutinin from influenza A virus; and (iii) a tag denoted PD designed to be pH-dependent in such a way that an amphiphatic alpha-helix would be formed at low pH . As an affinity tag, an IgG-binding domain Z derived from Staphylococcus aureus protein A (SpA) was used, and a malaria peptide M5, derived from the central repeat region of the Plasmodium falciparum blood-stage antigen Pf155/RESA, served as a model immunogen in this study . Three different fusion proteins, IW-Z-M5, MI-Z-M5 and PD-Z-M5, were produced in Escherichia coli, and after affinity purification these were evaluated in iscom-incorporation experiments . Two of the fusion proteins, IW-Z-M5 and MI-Z-M5 were found in the iscom fraction following preparative ultracentrifugation, indicating iscom incorporation . This was further supported by electron microscopy analysis showing that iscoms were formed . Furthermore, these iscom preparations were demonstrated to induce efficient M5-specific antibody responses upon immunization of mice, confirming successful incorporation into iscoms . The implications of these results for the design and production of subunit vaccines are discussed. N Engl J Med, 1999 Feb 18, 340(7), 493 - 501 Emergence of vancomycin resistance in Staphylococcus aureus . Glycopeptide-Intermediate Staphylococcus aureus Working Group; Smith TL et al.; BACKGROUND: Since the emergence of methicillin-resistant Staphylococcus aureus, the glycopeptide vancomycin has been the only uniformly effective treatment for staphylococcal infections . In 1997, two infections due to S . aureus with reduced susceptibility to vancomycin were identified in the United States . METHODS: We investigated the two patients with infections due to S . aureus with intermediate resistance to glycopeptides, as defined by a minimal inhibitory concentration of vancomycin of 8 to 16 microg per milliliter . To assess the carriage and transmission of these strains of S . aureus, we cultured samples from the patients and their contacts and evaluated the isolates . RESULTS: The first patient was a 59-year-old man in Michigan with diabetes mellitus and chronic renal failure . Peritonitis due to S . aureus with intermediate resistance to glycopeptides developed after 18 weeks of vancomycin treatment for recurrent methicillin-resistant S . aureus peritonitis associated with dialysis . The removal of the peritoneal catheter plus treatment with rifampin and trimethoprim-sulfamethoxazole eradicated the infection . The second patient was a 66-year-old man with diabetes in New Jersey . A bloodstream infection due to S . aureus with intermediate resistance to glycopeptides developed after 18 weeks of vancomycin treatment for recurrent methicillin-resistant S . aureus bacteremia . This infection was eradicated with vancomycin, gentamicin, and rifampin . Both patients died . The glycopeptide-intermediate S . aureus isolates differed by two bands on pulsed-field gel electrophoresis . On electron microscopy, the isolates from the infected patients had thicker extracellular matrixes than control methicillin-resistant S . aureus isolates . No carriage was documented among 177 contacts of the two patients . CONCLUSIONS: The emergence of S . aureus with intermediate resistance to glycopeptides emphasizes the importance of the prudent use of antibiotics, the laboratory capacity to identify resistant strains, and the use of infection-control precautions to prevent transmission. Diagn Microbiol Infect Dis, 1999 Jan, 33(1), 43 - 6 Activity of clinafloxacin, trovafloxacin, quinupristin/dalfopristin, and other antimicrobial agents versus Staphylococcus aureus isolates with reduced susceptibility to vancomycin; Cohen MA et al.; Isolations of Staphylococcus aureus strains with reduced susceptibility to vancomycin are now being reported worldwide . In testing here by broth microdilution according to NCCLS guidelines and applying vancomycin breakpoint criteria (susceptible at 4 micrograms/mL), two of three strains were susceptible (MICs at 4 micrograms/mL) rather than intermediate (MICs at 8 micrograms/mL) as previously reported by other laboratories . Clinafloxacin was more active (MICs/MBCs at 0.5 to 2 micrograms/mL) than ciprofloxacin, grepafloxacin, levofloxacin, ofloxacin, and sparfloxacin . Trovafloxacin, trimethoprim/sulfamethoxazole, and quinupristin/dalfopristin were the next most active agents, although quinupristin/dalfopristin was bactericidal against only two of these three strains . Amikacin, imipenem, oxacillin, and rifampin were less active. Diagn Microbiol Infect Dis, 1999 Jan, 33(1), 39 - 42 Comparison of ex-vivo serum bactericidal activity of cefepime, ceftazidime and cloxacillin against Staphylococcus aureus; Dan M et al.; Cefepime (1 g), ceftazidime (1 g), and cloxacillin (2 g) were administered intravenously to 10 volunteers each . After infusion of a single dose over 30 min, blood samples were obtained at 0.5, 1, 2, 3, 4, 5, 6, 8, 10, and 12 h (for ceftazidime at 0.5 and 4 h) after dosing . Drug levels were determined by the bioassay method . Serum bactericidal activity against five clinical isolates of cloxacillin-susceptible Staphylococcus aureus were determined by the microdilution method according to the National Committee for Clinical Laboratory Standards guidelines . The mean peak serum level was 76.88 +/- 24.71 mg/L for cefepime, 42.8 +/- 15.98 mL/L for ceftazidime, and 92.81 +/- 24.7 mg/L for cloxacillin . Concentrations of cefepime were detected during the whole testing period (mean trough level, 1.43 +/- 0.9 mg/L at 12 h), whereas concentrations of cloxacillin were measurable up to 5 h after administration (mean trough level, 0.90 +/- 0.97 mg/L) . The mean peak reciprocal bactericidal titers were 29.41 for cefepime, 5.6 for ceftazidime, and 377 for cloxacillin . Effective bactericidal titers were detected as long as 5 h for cefepime (approximately 40% of the dosing interval) and 3 h for cloxacillin (at least 50% of the dosing interval) . For ceftazidime, serum bactericidal activity was markedly lower compared with that of cefepime . Although cefepime has demonstrated an improved antistaphylococcal bactericidal activity compared with ceftazidime, it was somewhat lower than that of cloxacillin. Br J Dermatol, 1998 Dec, 139 Suppl 53, 37 - 40 Fusidic acid in dermatology; Wilkinson JD; Fusidic acid is an antibiotic that belongs to a group of its own, the fusidanes . The molecule has a steroid-like structure but does not possess any steroid activity . The structure is thought to be responsible for the steroid-like high penetration, and for the fact that no cross-resistance or cross-allergy has been seen with other antibiotics in routine clinical use . The anti-microbial activity of fusidic acid is specifically aimed at the most common skin pathogens, including Staphylococcus aureus, towards which it is one of the most potent antibiotics . The place of fusidic acid in dermatology is in the treatment of mild to moderately severe skin and soft-tissue infections, e.g . impetigo, folicullitis, erythrasma, furunculosis, abscesses and infected traumatic wounds, whereas it is of less use in conditions such as hidradenitis suppurativa, chronic leg ulcers, burns and pressure sores . The topical combinations of fusidic acid with either betamethasone or hydrocortisone are extremely useful in the treatment of atopic dermatitis/eczema whenever staphylococcal/secondary infection is suspected, and in more persistent cases of eczema where staphylococcal superantigen may be playing an important exacerbating role. Br J Dermatol, 1998 Dec, 139 Suppl 53, 13 - 6 Staphylococcus aureus colonization in atopic dermatitis and its therapeutic implications; Abeck D et al.; Skin colonization with Staphylococcus aureus is a characteristic feature of atopic dermatitis with more than 90% of patients being colonized . Extracellular matrix proteins are important for the adherence of S . aureus to human keratinocytes . The bacterium interferes in the inflammatory process of atopic dermatitis in various ways, among which the ability to release superantigens in a high percentage of clinical isolates is of great importance . As the colonization correlates significantly with the severity of eczema, anti-staphylococcal treatment measurements are widely used . In cases of atopic dermatitis exacerbation with wide-spread weeping lesions, a systemic antibiotic treatment is warranted, with erythromycin no longer being recommended due to an increased resistance rate . In localized superinfected lesions the topical application of an antibiotic-glucocorticoid preparation may offer advantages to the mere steroid application . Based on efficacy and resistance data, fusidic acid is the antibiotic of choice . There is evidence that phototherapy in atopic dermatitis may be even more effective when combined with anti-staphylococcal measurements . In the future new therapeutical options may be available. Proc Natl Acad Sci U S A, 1999 Feb 16, 96(4), 1218 - 23 Structure-activity analysis of synthetic autoinducing thiolactone peptides from Staphylococcus aureus responsible for virulence; Mayville P et al.; The synthesis of virulence factors and other extracellular proteins responsible for pathogenicity in Staphylococcus aureus is under the control of the agr locus . A secreted agr-encoded peptide, AgrD, processed from the AgrD gene product, is known to be an effector of self-strain activation and cross-strain inhibition of the agr response . Biochemical analysis of AgrD peptides isolated from culture supernatants has suggested that they contain an unusual thiol ester-linked cyclic structure . In the present work, chemical synthesis is used to confirm that the mature AgrD peptides contain a thiolactone structure and that this feature is absolutely necessary for full biological activity . The AgrD synthetic thiolactone peptides exhibited biological activity in vivo in a mouse protection test . Structure-activity studies have allowed key aspects of the peptide structure involved in the differential activation and inhibition functions to be identified . Accordingly, we propose a model for activation and inhibition of the agr response in which the former, but not the latter, involves specific acylation of the agr transmembrane receptor, AgrC. J Invest Dermatol, 1999 Feb, 112(2), 249 - 53 Evidence for superantigen involvement in skin homing of T cells in atopic dermatitis; Strickland I et al.; The environmental factors that contribute to the homing of T cells in skin disease is unknown . The skin lesions of atopic dermatitis (AD) are frequently colonized with superantigen (SAg), producing strains of Staphylococcus aureus . In vitro, these superantigens have the capacity to activate and expand T cells expressing specific T cell receptor BV gene segments, and also to increase their skin homing capacity via upregulation of the skin homing receptor, cutaneous lymphocyte-associated antigen (CLA) . These activities have been proposed to enhance the chronic cutaneous inflammation of AD, but an in vivo role for SAg has not been conclusively demonstrated . In this study, we sought direct evidence for in vivo SAg activity by comparing the SAg profiles of S . aureus cultured from the skin of AD subjects to the T cell receptor Vbeta repertoire of their skin homing (CLA+) T cells in peripheral blood . SAg secreting S . aureus strains were identified in six of 12 AD patients, and all of these subjects manifested significant SAg-appropriate Vbeta skewing within the CLA+ subsets of both their CD4+ and their CD8+ T cells . T cell receptor Vbeta skewing was not detectable among the overall CD4+ or CD8+ T cell subsets of these subjects, and was not present within the CLA+ T cell subsets of five patients with plaque psoriasis and 10 normal controls . T cell receptor BV genes from the presumptively SAg-expanded populations of skin homing T cells were cloned and sequenced from three subjects and, consistent with a SAg-driven effect, were found to be polyclonal . We conclude that SAg can contribute to AD pathogenesis by increasing the frequency of memory T cells able to migrate to and be activated within AD lesions. Biol Pharm Bull, 1999 Jan, 22(1), 73 - 6 Biological activities of 1,1,6-trisubstituted indanes: beyond magainin 2; Numao N et al.; MSI-78 is a peptide analog of naturally occurring magainin 2 isolated from the skin of Xenopus laevis . The peptide is known to have one of the strongest antibacterial activities in magainin 2 analogs against methicillin-resistant Staphylococcus aureus (MRSA) . To find novel compounds superior to MSI-78, we have further designed, synthesizing 1,1-di(4-aminobutyl)-6-benzylindane (PM4) and 1,1-dibenzyl-6-(4-aminobutyl) indane (PM5), and tested their inhibitory ability of the growth of S . aureus . In an in vitro assay, PM4 showed the same antibacterial activity against the bacterium as MSI-78, and non-hemolytic activity against human red blood cells (RBCs) at the MIC (minimum inhibitory concentration) value, in contrast to the latter . On the other hand, PM5 showed stronger antibacterial activity than MSI-78, but being still accompanied with hemolysis at the MIC value . Otherwise, stronger decarboxylase activity for oxaloacetate was observed in PM5, rather than magainin 2 analogs or Oxaldie 1 as a control peptide, but not in PM4. FEBS Lett, 1999 Jan 25, 443(2), 220 - 4 Programming of enzyme specificity by substrate mimetics: investigations on the Glu-specific V8 protease reveals a novel general principle of biocatalysis; Wehofsky N et al.; In this paper the universal validity of the substrate mimetic concept in enzymatic C-N ligations was expanded to anionic leaving groups based on the specificity determinants of Glu-specific endopeptidase from Staphylococcus aureus (V8 protease) . In an empirical way a specific mimetic moiety was designed from simple structure-function relationship studies . The general function of the newly developed substrate mimetics to serve as an artificial recognition site for V8 protease have been examined by hydrolysis kinetic studies . Enzymatic peptide syntheses qualify the strategy of substrate mimetics as a powerful concept for programming the enzyme specificity in the direction of a more universal application of enzymes in the general area of biocatalysis. Microb Drug Resist, 1998 Winter, 4(4), 277 - 88 Spread of a methicillin-resistant and multiresistant epidemic clone of Staphylococcus aureus in Argentina; Corso A et al.; One hundred forty-eight recent methicillin-resistant Staphylococcus aureus (MRSA) isolates collected from 13 hospitals in Argentina were examined for antibiotic susceptibility and clonal type, using hybridization with DNA probes specific for mecA and Tn554, and pulsed-field gel electrophoresis (PFGE) of chromosomal SmaI digests . The majority of the isolates (62.2%) shared the common PFGE B pattern and carried variants of mecA and Tn554 polymorphs characteristic of an MRSA clone widely spread in Brazilian hospitals . Similarly to the Brazilian isolates, the MRSA clone recovered in the Argentinian hospitals (XI::B::B) and its close relatives (XI::B'::B, XI::AA::B, XI::M::B, XI::omega omega::B, and III::W::B) showed susceptibility to spectinomycin and resistance to numerous antibacterial agents, including beta-lactams, tetracycline, aminoglycosides, macrolides, trimethoprim/sulfamethoxazole, ciprofloxacin, and fosfomycin, and more than 60% of the isolates were also resistant to chloramphenicol and rifampin . The XI::B::B MRSA clone represented the majority of isolates recovered in most of the hospitals, nine of which were located in the city of Buenos Aires, three in the province of Buenos Aires, and one in the province of Tucuman, 1,312 km northwest of the city of Buenos Aires . The observations document further geographic expansion of this South American MRSA clone across national boundaries. J Protein Chem, 1998 Nov, 17(8), 827 - 34 The complete amino acid sequence of a trypsin inhibitor from Bauhinia variegata var . candida seeds; Di Ciero L et al.; Trypsin inhibitors of two varieties of Bauhinia variegata seeds have been isolated and characterized . Bauhinia variegata candida trypsin inhibitor (BvcTI) and B . variegata lilac trypsin inhibitor (BvlTI) are proteins with Mr of about 20,000 without free sulfhydryl groups . Amino acid analysis shows a high content of aspartic acid, glutamic acid, serine, and glycine, and a low content of histidine, tyrosine, methionine, and lysine in both inhibitors . Isoelectric focusing for both varieties detected three isoforms (pI 4.85, 5.00, and 5.15), which were resolved by HPLC procedure . The trypsin inhibitors show Ki values of 6.9 and 1.2 nM for BvcTI and BvlTI, respectively . The N-terminal sequences of the three trypsin inhibitor isoforms from both varieties of Bauhinia variegata and the complete amino acid sequence of B . variegata var . candida L . trypsin inhibitor isoform 3 (BvcTI-3) are presented . The sequences have been determined by automated Edman degradation of the reduced and carboxymethylated proteins of the peptides resulting from Staphylococcus aureus protease and trypsin digestion . BvcTI-3 is composed of 167 residues and has a calculated molecular mass of 18,529 . Homology studies with other trypsin inhibitors show that BvcTI-3 belongs to the Kunitz family . The putative active site encompasses Arg (63)-Ile (64). Mol Microbiol, 1998 Dec, 30(5), 991 - 1001 SarA level is a determinant of agr activation in Staphylococcus aureus; Chien Y et al.; The control of virulence determinant expression in Staphylococcus aureus is a complex process involving global regulatory loci such as sar and agr . The sar locus consists of a 372 bp sarA open reading frame (ORF) preceded by a triple promoter region interspersed with two putative smaller ORFs (ORF3 and ORF4) . The triple promoter system yields three overlapping sar transcripts (sarA, sarC and sarB of 0.56, 0.8 and 1.2 kb respectively) . We have recently shown that the SarA protein binds to the agr promoter region to stimulate the transcription of RNAII and RNAIII, two major transcripts encoded within the agr locus . To assess the role of the region upstream of sarA in agr expression, we evaluated the contribution of ORF3 and ORF4 to SarA protein expression and to agr activation by introducing nonsense mutations into the respective ORFs . Northern analysis of sar mutant clones containing these mutations carried on a shuttle plasmid revealed that all three sar-related transcripts are present . Using anti-SarA monoclonal antibodies with defined epitopes in a competitive ELISA to determine the SarA protein level, we found that the introduction of a stop codon in ORF3 on a shuttle plasmid carrying the intact sar locus in a sar mutant led to a significant decrease in SarA protein level compared with the non-mutated control . The effect of a nonsense mutation in ORF4 on SarA levels is much less . Likewise, an analogous sar mutant clone with a deletion in ORF3 also displayed a lower SarA level than its intact counterpart . The reduction in SarA expression correlated with a lower level of agr activation in the corresponding sar mutant clone . These data suggest that ORF3, and to a lesser degree ORF4, may affect agr expression by modulating SarA protein expression. Clin Exp Obstet Gynecol, 1998, 25(4), 119 - 20 Methicillin resistant Staphylococcus aureus as a cause of chorioamnionitis; Geisler JP et al.; BACKGROUND: Chorioamnionitis is a leading cause of morbidity and mortality in preterm infants . Only rarely is Staphylococcus aureus implicated . A case of methicillin resistant Staphylococcus aureus causing chorioamnionitis and endometritis is presented . CASE REPORT: A 39-year-old gravida 2 para 1 female, who previously worked as the unit clerk in the pediatric pulmonary unit of a children's hospital, was initially admitted at 22 weeks with a shortened cervix . The patient refused emergency cerclage . She was released from the hospital and returned at 25 4/7 weeks' estimated gestational age with possible spontaneous rupture of membranes . An amniocentesis was performed and revealed a gram stain positive for many gram positive cocci as well as a glucose of < 2 mg% . The patient was started on intravenous ampicillin and gentamicin and induction of labor with oxytocin was begun . Approximately 1 day after the patient's delivery, the culture from the amniocentesis was noted to have grown methicillin resistant Staphylococcus aureus, and the patient's (as well as the neonate's) regimen was switched to vancomycin . CONCLUSION: A Medline search revealed no cases of methicillin resistant Staphylococcus aureus causing chorioamnionitis . When chorioamnionitis or refractory endometritis is encountered in a patient who works in the health care industry, methicillin resistant staphylococcus aureus must be considered. Vaccine, 1999 Jan, 17(2), 126 - 33 Epitopic overload at the site of injection may result in suppression of the immune response to combined capsular polysaccharide conjugate vaccines; Fattom A et al.; Capsular polysaccharide (CP) conjugate vaccines targeting a variety of bacterial infections are currently under development and clinical evaluation . The inclusion of multiple CP serotypes combined in a single injection is an important maneuver being evaluated . The combination of CP conjugate vaccines into a single multivalent injection may result in competition among the different components and adversely affect the immunogenicity of any individual conjugate . We observed a reduction of 30-90% in antibody responses to several serotypes in mice when immunogenicity of a 12-valent Escherichia coli (E . coli) lipopolysaccharide (LPS) conjugate vaccine was compared to the immunogenicity of each monovalent vaccine evaluated separately . A reduction of 30% was observed in the Staphylococcus aureus (S . aureus) type 8 CP antibodies when a type 8-rEPA conjugate was combined with a type 5-rEPA conjugate . S . aureus types 5 and 8-rEPA conjugates were combined with 100 micrograms of either rEPA (homologous) or diphtheria toxoid (DT) (heterologous) carrier proteins, and evaluated in rEPA or DT primed mice . The addition of the homologous protein resulted in a 64% reduction in type 5 CP antibodies . The heterologous protein did not affect the immunogenicity of the type 5 . We postulate that the free protein competed with the conjugate and recruited most of the rEPA primed T cells . In the case of the DT conjugates, the DT targeted different populations of the T cells, thus interference was not observed . These data suggested that the epitopic load rather than the antigenic load at the site of injection caused reduced immunogenicity of the conjugates . We theorize that individual components of multivalent CP vaccines conjugated to the same carrier proteins would compete for a limited number of specific carrier protein primed T cells . This would result in one or more components being unavailable in eliciting a sufficient immune response . The use of multiple carrier proteins should be considered as an approach to reduce interference when multivalent conjugate vaccines are to be formulated into a single injection. J Clin Microbiol, 1999 Mar, 37(3), 690 - 3 Rapid detection of epidemic strains of methicillin-resistant Staphylococcus aureus; Wichelhaus TA et al.; Fifty methicillin-resistant Staphylococcus aureus (MRSA) initial isolates obtained from patients hospitalized in the orthopedic clinic of the Frankfurt University Hospital and 150 methicillin-sensitive Staphylococcus aureus (MSSA) isolates were investigated in this study to determine whether the Slidex Staph-Kit is capable of differentiating between MRSA and MSSA owing to its unique performance characteristics . The Slidex Staph-Kit is a combined latex hemagglutination test designed to detect clumping factor, protein A, and a specific surface immunogen for S . aureus . Clumping factor-positive strains cause erythrocytes sensitized with fibrinogen to hemagglutinate, thereby resulting in visible red clumps . S . aureus strains deficient in clumping factor agglutinate latex particles sensitized with specific antibodies against surface proteins of S . aureus, thereby resulting in visible white clumps . Our results demonstrate that white clumping has a 99% specificity as well as a 98% positive predictive value for MRSA . Clumping factor-negative MRSA, which have been reported to occur in several countries, are epidemic in the Frankfurt area and account for 80% of all MRSA initial isolates in the orthopedic clinic of the Frankfurt University Hospital . Genotyping of all MRSA isolates by macrorestriction analysis of chromosomal DNA revealed that 83% of clumping factor-negative MRSA are closely related to the "southern-German" epidemic strain . This is the first study demonstrating the Slidex Staph-Kit's capability for identifying epidemic clumping factor-negative S . aureus strains as methicillin resistant even prior to antimicrobial susceptibility testing. J Clin Microbiol, 1999 Mar, 37(3), 664 - 74 Validation of binary typing for Staphylococcus aureus strains; van Leeuwen W et al.; Most of the DNA-based methods for genetic typing of Staphylococcus aureus strains generate complex banding patterns . Therefore, we have developed a binary typing procedure involving strain-differentiating DNA probes which were generated on the basis of randomly amplified polymorphic DNA (RAPD) analysis . We present and validate the usefulness of 15 DNA probes, according to generally accepted performance criteria for molecular typing systems . RAPD analysis with multiple primers was performed on 376 S . aureus strains of which 97% were methicillin resistant (MRSA) . Among the 1,128 RAPD patterns generated, 66 were selected which identified 124 unique DNA fragments . From these amplicons, only 12% turned out to be useful for isolate-specific binary typing . The nature of the RAPD-generated DNA fragments was investigated by partial DNA sequence analysis . Several homologies with known S . aureus sequences and with genes from other species were discovered; however, 87% of the probe sequences are of previously unknown origin . The locations of most of the DNA probes on the chromosome of S . aureus NCTC 8325 were determined by hybridization . Seven fragments were randomly dispersed along the genome, five were clustered within the 2500- to 2600-kb position of the genome, and the remaining four did not recognize complementary sequences in S . aureus NCTC 8325 . A total of 103 S . aureus strains (69% MRSA) were used for the validation of the binary typing technique . The 15 DNA probes provided stable epidemiological markers, both in vitro (type consistency after serial passages on culture media) and in vivo (comparison of sequential isolates recovered from cases of persistent colonization) . The discriminatory power of binary typing (D = 0.998) exceeded that of pulsed-field gel electrophoresis (D = 0.966) and RAPD analysis (D = 0.949) . Reproducibility, measured by analyzing multiple strains belonging to a multitude of different epidemiological clusters, was comparable to that of other genotyping techniques used . Contribution of the DNA probes to the discriminatory power of the system was analyzed by comparison of dendrograms . This study demonstrates that binary typing is a robust tool for the genetic typing of S . aureus isolates. J Clin Microbiol, 1999 Mar, 37(3), 570 - 4 Rapid identification and typing of Staphylococcus aureus by PCR-restriction fragment length polymorphism analysis of the aroA gene; Marcos JY et al.; The Staphylococcus aureus aroA gene, which encodes 5-enolpyruvylshikimate-3-phosphate synthase, was used as a target for the amplification of a 1,153-bp DNA fragment by PCR with a pair of primers of 24 and 19 nucleotides . The PCR products, which were detected by agarose gel electrophoresis, were amplified from all S . aureus strains so far analyzed (reference strains and isolates from cows and sheep with mastitis, as well as 59 isolates from humans involved in four confirmed outbreaks) . Hybridization with an internal 536-bp DNA fragment probe was positive for all PCR-positive samples . No PCR products were amplified when other Staphylococcus spp . or genera were analyzed by using the same pair of primers . The detection limit for S . aureus cells was 20 CFU when the cells were suspended in saline; however, the sensitivity of the PCR was lower (5 x 10(2) CFU) when S . aureus cells were suspended in sterilized whole milk . TaqI digestion of the PCR-generated products rendered two different restriction fragment length polymorphism patterns with the cow and sheep strains tested, and these patterns corresponded to the two different patterns obtained by antibiotic susceptibility tests . Analysis of the 59 human isolates by our easy and rapid protocol rendered results similar to those of other assays. J Clin Microbiol, 1999 Mar, 37(3), 504 - 9 Dissemination of two methicillin-resistant Staphylococcus aureus clones exhibiting negative staphylase reactions in intensive care units; Hsueh PR et al.; From December 1997 to March 1998, 25 methicillin-resistant Staphylococcus aureus (MRSA) isolates exhibiting negative Staphylase (Oxoid Ltd., Basingstoke, England) reactions were identified from various clinical specimens from 13 patients in six intensive care units (ICUs) or in wards following a stay in an ICU at the National Taiwan University Hospital . The characteristics of these isolates have not been previously noted in other MRSA isolates from this hospital . Colonies of all these isolates were grown on Trypticase soy agar supplemented with 5% sheep blood and were nonhemolytic and unpigmented . Seven isolates, initially reported as Staphylococcus haemolyticus (5 isolates) and Staphylococcus epidermidis (2 isolates) by the routine identification scheme and with the Vitek GPI system (bioMerieux Vitek, Inc., Hazelwood, Mo.), were subsequently identified as S . aureus by positive tube coagulase tests, standard biochemical reactions, and characteristic cellular fatty acid chromatograms . The antibiotypes obtained by the E test, coagulase types, restriction fragment length polymorphism profiles of the staphylococcal coagulase gene, and random amplified polymorphic DNA patterns generated by arbitrarily primed PCR of the isolates disclosed that two major clones disseminated in the ICUs . Clone 1 (16 isolates) was resistant to clindamycin and was susceptible to trimethoprim-sulfamethoxazole (TMP-SMZ) and was coagulase type II . Clone 2 (eight isolates) was resistant to clindamycin and TMP-SMZ and was coagulase type IV . These two epidemic clones from ICUs are unique and underline the need for caution in identifying MRSA strains with colonial morphologies not of the typical type and with negative Staphylase reactions. J Toxicol Environ Health A, 1999 Feb 12, 56(3), 165 - 82 Differential regulation of in vitro cytokine production by human blood cells in response to methylmethacrylate; Liu Y et al.; The effect of methylmethacrylate (MMA) on human whole blood cultures (WBC) obtained from healthy donors was investigated . Lymphocyte transformation and cytokine production, that is, interleukin 6 (IL-6), interferon-gamma (IFN-gamma), and tumor necrosis factor-alpha (TNF-alpha), were used to evaluate the immunological activities of MMA . Primary cytotoxicity testing of MMA in Jurkat cells showed that this compound decreased the cell proliferation to 50% at a concentration of >60 mmol/L . Similarly, MMA significantly decreased lymphocyte transformation in either phytohemagglutinin (PHA) or Staphylococcus aureus protein A (SpA) activated WBC at 100 mmol/L . In contrast to activated WBC, MMA had no observed effect on resting blood cells . Cytokine expression in WBC seemed differentially modulated by MMA . There was a tendency for IL-6 production in both resting and PHA-stimulated WBC to be upregulated, while IL-6 induced in SpA stimulated cultures was downregulated . TNF-alpha was slightly increased by MMA in resting WBC at early incubation periods, and it was slightly downregulated in response to PHA or SpA activation . Suppression of IFN-gamma secretion was observed in WBC with or without PHA or SpA stimulation . The overall results demonstrated that MMA at physiological levels could influence the cytokine production in normal human blood cells in vitro . Alterations of cytokine production patterns by MMA indicate that this compound has multiple regulatory effects on immune reactions in normal human blood. Reg Anesth Pain Med, 1999 Jan-Feb, 24(1), 24 - 9 Effect of Staphylococcus aureus bacteria and bacterial toxins on meningeal permeability in vitro; Ummenhofer WC et al.; BACKGROUND AND OBJECTIVES: Epidural catheterization is associated with a significant bacterial colonization rate and occasionally frank infection . During epidural space infection, decreased analgesia despite increased epidural opioid doses has been described . One possible explanation for this observation is that bacterial infection decreases meningeal permeability . The purpose of the study was to determine whether Staphylococcus aureus bacteria, the most common organism causing epidural space infection, or S . aureus toxins alter meningeal permeability . METHODS: Spinal meninges of M . nemestrina monkeys were mounted in a previously established in vitro diffusion cell model and exposed to S . aureus toxins A, B, and F . Simultaneous transmeningeal fluxes of mannitol and sufentanil were measured before and after toxin exposure and compared to controls . In a second series of experiments, diffusion cells were inoculated with live S . aureus bacteria in suspension and the permeability of sufentanil was investigated . RESULTS: Staphylococcus aureus toxin-A increased the transmeningeal flux of mannitol but not sufentanil . Toxins B and F did not alter the meningeal permeability of either drug . Inoculation with live S . aureus bacteria increased the transmeningeal flux of sufentanil by 115+/-21% (P = .032) . CONCLUSIONS: These data demonstrate that S . aureus alpha-toxin and live S . aureus bacteria can increase meningeal permeability . Thus, clinical observations of decreased epidural analgesia in the face of bacterial infection cannot be explained by decreased meningeal permeability. Minerva Anestesiol, 1998 Nov, 64(11), 529 - 34 {Therapeutic objectives and strategies in NBIA 1 (Hallovorden-Spatz syndrome)}; Bruscoli F et al.; A 10 years old male patient, DG, was admitted in the ICU because of continuous uncontrolled movements due to a neurologycal degenerative disease (Hallervorden-Spatz syndrome) able to determine reduction of spontaneous breathing efficacy . At admission he presented acute ventilatory failure, because of a Staphylococcus aureus broncopneumonia, so he had a tracheal tube and mechanical ventilation (pressure support) . During hospitalization (4 months in ICU and 2 months in Pediatric Department) DG received tracheotomy and percutaneous gastrostomy, to obtain adequate spontaneous ventilation and artificial enteral nutrition; a satisfactory pharmacological control of choreo-athetosic movements, with not great interference with original sleep-awake cycle, was obtained . Actually DG is living in his family (9 months follow-up); he has tracheotomy and percutaneous gastrostomy; he can relate with the environment; in a few months, he'll go to school again . He need 30 daily administrations of 8 different drugs; family, supported by an integrated multidisciplinary equipe, takes care of him . The role of Intensivist is essential not only in the management of acute phases in chronic diseases, but also in the longterm management of a homely care. Vet Immunol Immunopathol, 1999 Jan 4, 67(1), 47 - 54 Pregnancy-associated glycoprotein and decreased polymorphonuclear leukocyte function in early post-partum dairy cows; Dosogne H et al.; Phagocytosis and oxidative burst activity of polymorphonuclear neutrophil leukocytes (PMN) isolated from blood and pregnancy-associated glycoprotein (bPAG) concentrations in plasma were evaluated in two longitudinal studies in dairy cows from 3 weeks before until 5 weeks after calving, carried out in the United States and in Europe . Ingestion of Staphylococcus aureus by blood PMN increased during the first week after calving and normalised 3 weeks post-partum . Phagocytosis of Escherichia coli did not change in the early post-partum period . In both studies, a significant decrease in oxidative burst activity of PMN was observed between 1 and 3 weeks after calving . In all cows, a very significant increase in plasma bPAG concentration was found between 1 week before and 2 weeks after calving . The peak of bPAG concentration in plasma immediately preceded the alterations of blood PMN functions . These results suggest that bPAG may be associated with inhibition of PMN function of dairy cows during the early post-partum period. Invest Ophthalmol Vis Sci, 1999 Feb, 40(2), 385 - 91 Acute inflammation of the eyelid and cornea in Staphylococcus keratitis in the rabbit; Sloop GD et al.; PURPOSE: The inflammatory response during Staphylococcus keratitis was analyzed biochemically and histologically to determine the source of the neutrophils infiltrating the tear film and cornea . METHODS: Rabbit eyes were swabbed and then examined by slit-lamp microscopy at 0, 5, 10, 15, 20, and 25 hours after intracorneal inoculation with Staphylococcus aureus . Bacterial colony-forming units were quantified in the cornea, eyelid, and acute inflammatory exudate . Myeloperoxidase activity of ocular swabs of acute inflammatory exudate, corneal homogenates, and eyelid homogenates was determined . Gross and microscopic examinations of corneas and eyelids were performed . RESULTS: The colony-forming units per cornea exceeded 10(7) after 10 hours, whereas no bacteria were cultured from the eyelid until 15 hours postinfection . Slit-lamp examination revealed progressive pathology, and the myeloperoxidase activities of ocular swabs, corneas, and eyelids increased markedly by 15 hours postinfection . Corneas showed a wave of neutrophils moving from the tear film toward bacteria in the central corneal stroma and early neutrophil migration from the limbus into the stroma . In the eyelid, neutrophils migrated from the stromal vessels to the tear film . CONCLUSIONS: Staphylococcus keratitis in the rabbit causes acute inflammation in the overlying eyelid . Neutrophils of the acute inflammatory exudate interact with the infected cornea, whereas neutrophils migrating through the cornea from the limbus remained distant from the site of infection. J Emerg Med, 1999 Jan-Feb, 17(1), 207 - 11 Staphylococcus aureus isolation from the lesions, the hands, and anterior nares of patients with atopic dermatitis; Williams JV et al.; Staphylococcus aureus colonization is common in atopic dermatitis (AD) and can exacerbate the disease . Some patients with atopic dermatitis may act as a reservoir for S . aureus transmission to others . This study compared S . aureus colonization in atopic dermatitis patients and their caregivers with control patients and their caregivers . Quantitative cultures were obtained from the lesions, clinically normal skin, hands, and anterior nares of 100 patients with atopic dermatitis, 100 controls with other cutaneous disorders, and 200 caregivers . The AD patients had significantly greater presence of S . aureus from lesional and clinically normal skin, as well as the hand . Significantly increased carriage of S . aureus was found in the anterior nares of caretakers of AD patients compared with control caretakers . Topical corticosteroid use did not affect recovery of S . aureus . There was a significant correlation between recovery of S . aureus from lesional skin and recovery from the anterior nares and hands . The nares and hands may be important reservoirs and vectors for autotransmission of S . aureus to lesional skin and for transmission to patients with AD. J Hosp Infect, 1999 Jan, 41(1), 39 - 44 An MRSA outbreak in a urology ward and its association with Nd:YAG coagulation laser treatment of the prostate; Jones JW et al.; An outbreak of methicillin resistant Staphylococcus aureus (MRSA) involving 88 patients in a general urology ward is described . Symptomatic bacteraemia and epididymo-orchitis occurred in 10 and 8% of patients respectively . Patients had a particularly high risk of acquiring serious MRSA infection after endoscopic neodymium yttrium aluminium garnet (Nd:YAG) laser treatment of the prostate . Appreciation of the mode of transmission of MRSA, a programme of continuing education for all medical and nursing staff, simple changes in ward protocol and advances in surgical laser technique contributed to the control of the outbreak. J Hosp Infect, 1999 Jan, 41(1), 29 - 37 Improved recognition of MRSA case clusters by the application of molecular subtyping using pulsed-field gel electrophoresis; Macfarlane L et al.; Methicillin-resistant Staphylococcus aureus (MRSA) is increasingly common in hospital and community populations, making the recognition of true nosocomial outbreaks more difficult . We have used pulsed-field gel electrophoresis (PFGE) with Sma I digestion to analyse retrospectively two perceived outbreaks of epidemic methicillin-resistant Staphylococcus aureus 15 (EMRSA 15) colonization . The first cluster of cases in patients and staff on a general ward (ward D) revealed three different antibiograms based on differences in ciprofloxacin and rifampicin sensitivities . All isolates typed using PFGE, which was more discriminatory than phage-typing . One PFGE banding profile labelled type 5 was predominant, but 12 isolates proved to be subtypes of type 5 and two were PFGE type 11 . Four staff members carried a strain not found in patients, three carried strains found in patients and transient carriage was highlighted as a problem when screening staff . PFGE enhanced the epidemiological data and proved that the cases on this ward did not comprise one large outbreak but numerous sporadic cases and smaller clusters . In contrast, isolates from a second cluster of cases which occurred on ward F were indistinguishable using antibiograms, phage-typing and PFGE, confirming this was more likely to be a true outbreak of colonization . We conclude that PFGE usefully augments epidemiological information and allows more logical infection control decisions to be made, with better utilization of scarce resources. J Nucl Med, 1999 Jan, 40(1), 192 - 7 A novel method to label liposomes with 99mTc by the hydrazino nicotinyl derivative; Laverman P et al.; In this study a new 99mTc labeling method for polyethyleneglycol (PEG)-coated liposomes is described . The in vitro and in vivo characteristics were compared with the conventional 99mTc-HMPAO-labeled PEG-coated liposomes . METHODS: PEG-coated liposomes were labeled with 99mTc by the hydrazino nicotinyl (HYNIC) derivative of distearoylphosphatidyl-ethanolamine (DSPE) and compared with PEG-coated liposomes labeled with 99mTc-HMPAO . In vitro stability tests were performed . Biodistribution and imaging characteristics of both liposomal preparations were determined in rats with Staphylococcus aureus infection in the left calf muscle . Results: Per liposome, 230 hydrazine groups were incorporated . The labeling efficiency of the 99mTc-HYNIC liposomes was greater than 95%, so no postlabeling purification was required, in contrast to the 99mTc-HMPAO liposomes . The 99mTc-HYNIC liposomes showed greater in vitro stability than the conventional 99mTc-HMPAO liposomes . Abscess uptake of the 99mTc-HYNIC liposomes was significantly greater (1.74+/-0.38%ID/g versus 1.26+/-0.29%ID/g, 24 h postinjection, P < 0.03) . Furthermore, kidney uptake of the 99mTc-HYNIC liposomes was one third of the uptake of the 99mTc-HMPAO liposomes (0.79+/-0.07%ID/g versus 2.47+/-0.35%ID/g, 24 h postinjection, P < 0.0001) . CONCLUSION: This new 99mTc-HYNIC-based labeling method for liposomes is rapid, efficient and easy to perform . Most importantly, the 99mTc-labeled liposomes have an improved stability and in vivo characteristics . The new labeling method is a major step forward toward a radiopharmaceutical for infection imaging that can be prepared in a one-step procedure within 15 min at room temperature and thus can be applied in every routine clinical practice. Surg Today, 1999, 29(1), 10 - 5 Tumor necrosis factor-alpha production after esophageal cancer surgery: differences in the response to lipopolysaccharide stimulation among whole blood, pleural effusion cells, and bronchoalveolar lavage fluid cells; Kimura Y et al.; The body's defense mechanism in response to stress may appear to be the sum of activation and suppression . We investigated chronological changes in tumor necrosis factor-alpha (TNF-alpha) production by local effusion cells and whole blood of esophageal cancer patients who had undergone radical resection . Whole blood, pleural effusion cells, and bronchoalveolar lavage fluid (BALF) cells were obtained from the 20 patients . Whole blood was stimulated with Escherichia coli (1 microg/ml), Staphylococcus aureus (10 microg/ml), and lipopolysaccharide (LPS) (1 microg/ml), and pleural effusion cells and BALF cells were stimulated with LPS; 24-H incubation and TNF-alpha concentration in supernate was measured by enzyme-linked immunosorbent assay (ELISA) . Within 3 h after starting the operation, TNF-alpha production in whole blood was significantly (P < 0.05) decreased compared with preoperative value by each stimulation, and this suppression persisted up to day 3 . These reductions in postoperative TNF-alpha production correlated with intraoperative hemorrhage . On the other hand, the LPS-induced release of TNF-alpha into pleural effusion cells and BALF cells were markedly increased during the study period . These results indicate that large quantities of cytokines are produced by a second attack, such as infection, in areas where immunocytes accumulate . We believe that the body reacts to surgical stress in a variety of ways . Circulating blood and immunocytes that accumulate in damaged organs are thought to react very differently to stress. Z Naturforsch {C}, 1998 Nov-Dec, 53(11-12), 1040 - 4 Correlation between virulence of various strains of mycobacteria and their susceptibility to ethanolic extract of propolis (EEP); Scheller S et al.; Ethanol extract of propolis (EEP) has antibacterial, antiviral, antiprotozoal and antifungal properties, in addition to many biological effects . Our laboratory has demonstrated a synergistic effect of EEP and antibiotics on the growth of Staphylococcus aureus, and suggested that the bactericidal effect of EEP was expressed mainly on virulent mycobacteria rather than on non-virulent (attenuated) ones . The present study was designed to reconfirm the latter finding, by subjecting 17 different mycobacteria strains to EEP, and evaluating whether there is a correlation between the virulence of the mycobacteria strains studied and their susceptibility to EEP . Our findings demonstrate that while the four non-virulent strains studied are not susceptible to EEP, out of the 13 virulent strains studied seven are susceptible and six are resistant to it . These results suggest that while there is no full correlation between virulence of the mycobacteria tested and their susceptibility to EEP, the few strains that were resistant to EEP were non-virulent. Clin Exp Immunol, 1999 Jan, 115(1), 95 - 102 Complement depletion aggravates Staphylococcus aureus septicaemia and septic arthritis; Sakiniene E et al.; The aim of the study was to assess the role of the complement system in Staphylococcus aureus arthritis and septicaemia . The murine model of haematogenously acquired septic arthritis was used, injecting intravenously toxic shock syndrome toxin-1 (TSST-1), producing S . aureus LS-1 . Complement was depleted using cobra venom factor (CVF) . Evaluation of arthritis was performed clinically and histopathologically . In addition, the effect of complement depletion on the phagocytic activity of leucocytes was assessed in vivo and in vitro . Six days after inoculation of S . aureus the prevalence of arthritis in decomplemented mice was three-fold higher than that in controls (91% versus 25%) . The clinical severity of arthritis at the end of the experiment, expressed as arthritic index, was 7.3 and 1.9, respectively . These findings were confirmed by histological index of synovitis as well as of cartilage and/or bone destruction being significantly higher in decomplemented mice than in controls (9.8 +/- 1.7 versus 4.9 +/- 1.2, P < 0.05; and 7.9 +/- 1.7 versus 3.0 +/- 0.9, P < 0.05, respectively) . Also, the septicaemia-induced mortality was clearly higher in decomplemented mice compared with the controls . CVF treatment significantly reduced in vivo polymorphonuclear cell-dependent inflammation induced by subcutaneous injection of olive oil and mirroring the capacity of polymorphonuclear cells (PMNC) to migrate and/or extravasate . Besides, the decomplementation procedure significantly impaired phagocytic activity of peripheral blood leucocytes in vitro, since the number of phagocytes being able to ingest bacteria decreased by 50% when the cells were maintained in decomplemented serum compared with those in intact serum . The conclusion is that complement depletion aggravates the clinical course of S . aureus arthritis and septicaemia, possibly by a combination of decreased migration/extravasation of PMNC and an impairment of phagocytosis. Biophys J, 1999 Feb, 76(2), 837 - 45 Genetically engineered metal ion binding sites on the outside of a Channel's transmembrane beta-barrel; Kasianowicz JJ et al.; We are exploring the ability of genetically engineered versions of the Staphylococcus aureus alpha-hemolysin (alphaHL) ion channel to serve as rationally designed sensor components for analytes including divalent cations . We show here that neither the hemolytic activity nor the single channel current of wild-type alphaHL was affected by {Zn(II)} </= 1 mM . Binding sites for the divalent cations were formed by altering the number and location of coordinating side chains, e.g., histidines and aspartic acids, between positions 126 and 134, inclusive . Several mutant alphaHLs exhibited Zn(II)-induced current noise that varied with Zn(II) concentration . At a fixed divalent cation concentration, the current fluctuation kinetics depended on the analyte type, e.g., Zn(II), Cu(II), Ni(II), and Co(II) . We also show that the ability of Zn(II) to change the mutant channel current suggests that the pore's topology is beta-sheet and that position 130 is near the turn at the trans mouth . Both conclusions are consistent with the crystal structure of WT-alphaHL oligomerized in detergent . Our results, in the context of the channel's crystal structure, suggest that conductance blockades were caused by Zn(II) binding to the outside surface of the pore . Thus, analyte-induced current blockades alone might not establish whether an analyte binding site is inside a pore. Eur J Epidemiol, 1998 Dec, 14(8), 807 - 16 Molecular characterization of methicillin-resistant Staphylococcus aureus (MRSA) in a university hospital in Italy; Villari P et al.; The molecular epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) in a university hospital in Italy was studied in a five-month period in 1996, during which all S . aureus isolated were collected . All MRSA isolates (95) and a sample of methicillin-susceptible S . aureus (20) were typed with a variety of phenotypic and genotypic methods . Clonal identities were determined by pulsed-field gel electrophoresis (PFGE) of chromosomal SmaI digests and, for MRSA isolates, by probing ClaI digests with a mecA probe and a Tn554 probe . Overall, MRSA represented 32.3% of all isolates, with very high percentages from the intensive care units (adult and neonatal) . PFGE after restriction with SmaI resolved genomic DNA of 95 MRSA strains into 26 major PFGE patterns . The use of southern blot hybridization of ClaI genomic digests with mecA and Tn554 allowed us a significant increase in discrimination, differentiating at least 32 different clones . Two major clones, however, each sharing common ClaI-mecA and Tn554 type and PFGE pattern as well as a common resistance phenotype, represented more than 50% of all MRSA isolates . The recovery of these two clones in the majority of the isolates of adult and neonatal intensive care units, respectively, is indicative of typical nosocomial outbreaks and clonal spread . It is concluded that intensive care units are major areas requiring preventative interventions. Infect Control Hosp Epidemiol, 1999 Jan, 20(1), 31 - 6 Methicillin-resistant Staphylococcus aureus and antimicrobial use in Belgian hospitals; Crowcroft NS et al.; OBJECTIVE: To investigate relationships between the incidence of methicillin-resistant Staphylococcus aureus (MRSA) and the use of different classes of antimicrobials in Belgian hospitals . DESIGN: Using Pearson correlation coefficients, the number of new nosocomial MRSA-colonized or -infected patients in the second half of 1994 and the first half of 1995 reported by the national MRSA surveillance program was compared with use of various antimicrobial classes as reported by the National Institute for Sickness and Disability Insurance . Relationships between different classes of antimicrobials were evaluated in a correlation matrix . MRSA incidence, antimicrobial use, and potential confounding factors were included in a multiple linear regression analysis . SETTING: 50 hospitals in Belgium . RESULTS: The use of a number of different classes of antimicrobials was interrelated . In the multivariate analysis, the incidence of nosocomial MRSA increased with increasing use of ceftazidime and cefsulodin (P=.0003), amoxicillin with clavulanic acid (P=.02), and quinolones (P=.005) . No association was found between MRSA incidence and total antimicrobial use . CONCLUSIONS: The relationships between antimicrobial use and MRSA are complex . Interventions aimed at promoting more rational prescribing patterns should be supported by adequate experimental and epidemiological evidence . Advice for preventing and controlling MRSA has focused mainly on hygienic measures and precautions to avoid cross-transmission; the role of relieving antimicrobial pressure needs to be clarified. Infect Control Hosp Epidemiol, 1999 Jan, 20(1), 26 - 30 Risk factors for colonization or infection due to methicillin-resistant Staphylococcus aureus in HIV-positive patients: a retrospective case-control study; Onorato M et al.; OBJECTIVE: To determine the risk factors for colonization or infection with methicillin-resistant Staphylococcus aureus in human immunodeficiency virus (HIV)-infected patients . DESIGN: Retrospective matched-pair case-control study . SETTING: Continuity clinic and inpatient HIV service of a university medical center . POPULATION: Patients with HIV infection from the general population of eastern and coastal Texas and from the Texas Department of Criminal Justice . DATA COLLECTION: Patient charts and the AIDS Care and Clinical Research Program Database were reviewed for the following: age, race, number of admissions, total hospital days, presence of a central venous catheter, serum albumin, total white blood cell count and absolute neutrophil count, invasive or surgical procedures, any cultures positive for S . aureus, and a history of opportunistic illnesses, diabetes, or dermatologic diagnoses . Data also were collected on the administration of antibiotics, antiretroviral therapy, steroids, cancer chemotherapy, and subcutaneous medications . RESULTS: In the univariate analysis, the presence of a central venous catheter, an underlying dermatologic disease, lower serum albumin, prior steroid therapy, and prior antibiotic therapy, particularly antistaphylococcal therapy or multiple courses of antibiotics, were associated with increased risk for colonization or infection with methicillin-resistant S . aureus . Multivariate analysis yielded a model that included presence of a central venous catheter, underlying dermatologic disease, broad-spectrum antibiotic exposure, and number of hospital days as independent risk factors for colonization or infection with methicillin-resistant S . aureus . CONCLUSIONS: In our HIV-infected patient population, prior hospitalization, exposure to broad-spectrum antibiotics, presence of a central venous catheter, and dermatologic disease were risk factors for acquisition of methicillin-resistant S . aureus. Spine, 1999 Jan 15, 24(2), 133 - 6 Epidural abscess of the cervical spine with osteomyelitis of the odontoid process; Wiedau-Pazos M et al.; STUDY DESIGN: A case report . OBJECTIVES: To document the rare condition of staphylococcal osteomyelitis of the odontoid process and to increase knowledge about the clinical characteristics and favorable outcome if patients are managed appropriately . SUMMARY OF BACKGROUND DATA: Osteomyelitis of the odontoid process caused by Staphylococcus aureus is a rare disease . A handful of cases have been reported within the last 30 years . Destructive odontoid peg involvement is most commonly associated with rheumatoid disease, which has a distinct clinical course compared with that of bacterial infection . METHODS: Two patients with bacterial osteomyelitis of the odontoid peg underwent medical and surgical treatment . They were observed for 3 years . All authors were involved in the care of these patients . RESULTS: Close monitoring of the patients' neurologic status and the use of noninvasive imaging techniques to evaluate the cervical spine led to an individualized treatment plan including antibiotic medication and transoral surgery with good outcomes in both cases . CONCLUSIONS: Awareness of the occurrence of bacterial osteomyelitis of the odontoid process, with or without neurologic symptoms, in patients with neck pain and fever may lead to earlier detection of this potentially critical condition, which has an excellent prognosis when treated early and appropriately. Antimicrob Agents Chemother, 1999 Feb, 43(2), 421 - 3 Comparative activities of clinafloxacin, grepafloxacin, levofloxacin, moxifloxacin, ofloxacin, sparfloxacin, and trovafloxacin and nonquinolones linozelid, quinupristin-dalfopristin, gentamicin, and vancomycin against clinical isolates of ciprofloxacin-resistant and -susceptible Staphylococcus aureus strains; Jones ME et al.; The activities of eight fluoroquinolones and linezolid, quinupristin-dalfopristin (Synercid), gentamicin, and vancomycin were tested against 96 ciprofloxacin-susceptible and 205 ciprofloxacin-resistant Staphylococcus aureus strains . Overall, clinafloxacin, followed by moxifloxacin and trovafloxacin, was the most active quinolone tested . For all isolates, linezolid and quinupristin-dalfopristin showed activities that were at least comparable to vancomycin, with no cross-resistance to any other test compound. Antimicrob Agents Chemother, 1999 Feb, 43(2), 354 - 6 Efflux pump-mediated quinolone resistance in Staphylococcus aureus strains wild type for gyrA, gyrB, grlA, and norA; Munoz-Bellido JL et al.; Fluoroquinolone efflux was studied in 47 Staphylococcus aureus clinical strains with MICs of ciprofloxacin (CFX) of < or = 2 micrograms/ml . Forty-three strains were wild type for gyrA, gyrB, and grlA quinolone resistance-determining regions and for norA and its promoter region . Forty of these strains (MICs of CFX, 0.1 to 0.2 microgram/ml) did not show efflux of fluoroquinolones . Three strains (MICs of CFX, 1 to 2 micrograms/ml) showed efflux . These results suggest that efflux can appear in S . aureus clinical strains in the absence of mutations in norA and its promoter. Antimicrob Agents Chemother, 1999 Feb, 43(2), 335 - 40 Effects of NorA inhibitors on in vitro antibacterial activities and postantibiotic effects of levofloxacin, ciprofloxacin, and norfloxacin in genetically related strains of Staphylococcus aureus; Aeschlimann JR et al.; NorA is a membrane-associated multidrug efflux protein that can decrease susceptibility to fluoroquinolones in Staphylococcus aureus . To determine the effect of NorA inhibition on the pharmacodynamics of fluoroquinolones, we evaluated the activities of levofloxacin, ciprofloxacin, and norfloxacin with and without various NorA inhibitors against three genetically related strains of S . aureus (SA 1199, the wild-type; SA 1199B, a NorA hyperproducer with a grlA mutation; and SA 1199-3, a strain that inducibly hyperproduces NorA) using susceptibility testing, time-kill curves, and postantibiotic effect (PAE) methods . Levofloxacin had the most potent activity against all three strains and was minimally affected by addition of NorA inhibitors . In contrast, reserpine, omeprazole, and lansoprazole produced 4-fold decreases in ciprofloxacin and norfloxacin MICs and MBCs for SA 1199 and 4- to 16-fold decreases for both SA 1199B and SA 1199-3 . In time-kill experiments reserpine, omeprazole, or lansoprazole increased levofloxacin activity against SA 1199-3 alone by 2 log10 CFU/ml and increased norfloxacin and ciprofloxacin activities against all three strains by 0.5 to 4 log10 CFU/ml . Reserpine and omeprazole increased norfloxacin PAEs on SA 1199, SA 1199B, and SA 1199-3 from 0.9, 0.6, and 0.2 h to 2.5 to 4.5, 1.1 to 1.3, and 0.4 to 1.1 h, respectively; similar effects were observed with ciprofloxacin . Reserpine and omeprazole increased the levofloxacin PAE only on SA 1199B (from 1.6 to 5.0 and 3.1 h, respectively) . In conclusion, the NorA inhibitors dramatically improved the activities of the more hydrophilic fluoroquinolones (norfloxacin and ciprofloxacin) . These compounds may restore the activities of these fluoroquinolones against resistant strains of S . aureus or may potentially enhance their activities against sensitive strains. Antimicrob Agents Chemother, 1999 Feb, 43(2), 240 - 5 glmM operon and methicillin-resistant glmM suppressor mutants in Staphylococcus aureus; Glanzmann P et al.; The Staphylococcus aureus phosphoglucosamine mutase gene glmM was shown to be the last gene of a three-cistron operon, orf1-orf2-glmM . One transcriptional start was identified upstream of orf1, and a second start producing a monocistronic transcript was identified upstream of glmM . Disruption of glmM abolished GlmM production, decreased methicillin resistance, and resulted in teicoplanin hypersusceptibility without affecting the production of the endogenous penicillin-binding proteins and PBP 2' . Complementation of the glmM mutation by the complete glmM operon restored both methicillin resistance and normal teicoplanin susceptibility . In contrast, a highly methicillin-resistant suppressor mutant obtained by selection for growth in the presence of methicillin remained GlmM deficient and teicoplanin hypersusceptible . The suppressor mutation was not linked to the glmM operon but was correlated with decreased autolysis and increased production of a 49-kDa protein, suggesting that there is an alternative pathway for glucosamine-1-phosphate synthesis in S . aureus. FEBS Lett, 1999 Jan 8, 442(1), 34 - 8 Characterization of the bleomycin resistance determinant encoded on the transposon Tn5; Kumagai T et al.; The transposon Tn5 carries a gene, ble, which confers resistance to bleomycin (Bm) and gives a survival advantage to its host cell . We found that the ble gene product, designated BLMT, is a binding protein with a strong affinity for Bm . BLMT quenched both the antibacterial and DNA-cleaving activities of Bm, when incubated with the antibiotic . An electron spin resonance spin-trapping analysis showed that BLMT inhibits the generation of Bm-induced hydroxyl radical, by trapping Bm but not the hydroxyl radical . Western blot analysis using an anti-BLMT monoclonal antibody revealed that BLMT is immunologically distinct from Bm-binding proteins from Streptomyces verticillus, Staphylococcus aureus and Streptoalloteichus hindustanus . Escherichia coli, transformed with a mutant ble having leucine instead of proline at N-terminal amino acid position 7, lost resistance to Bm, although the cell maintained the survival benefit . This suggests that the Bm resistance mediated by ble is independent of its ability to give a survival advantage to the host bacterium. Chirurgie, 1998 Dec, 123(6), 572 - 9 {Tricalcium phosphate, an antibiotic carrier: a study focused on experimental osteomyelitis in rabbits}; Lambotte JC et al.; PURPOSE OF THE STUDY: Macroporous beta tricalcium phosphate ceramic beads were elaborated to be a resorbable bone substitute and a drug delivery system carrying gentamicin or vancomycin . The aim of this study was to evaluate this implant into a rabbit experimental osteomyelitis . MATERIAL AND METHOD: Experimentation included 24 rabbits and was performed in three stages, according to Norden's description . Induction of osteomyelitis was obtained by injection of a sclerosing agent and of Staphylococcus aureus through the lateral side of the metaphysis of the proximal tibia . Three weeks after inoculation, animals were randomly dispatched to one of the three treatment groups . After surgical debridment (to collect cinetics data), the first group received no further treatment and was considered as a control; the second group received a ceramic implant; the third group received a gentamicin-loaded ceramic implant . Euthanasia occurred between 2 days and 21 days after the debridment . Bone samples were obtained to quantify the bacterial and gentamicin bone concentrations . Gentamicin level was also measured inside the ceramic implant . Antibiotic concentration was assessed by a immunoenzymatic method . RESULTS: Osteomyelitis was obtained in 21 of the 24 animals (87.5%) . Antibiotic release was early and complete (before the third day) but gentamicin still remained in the bone for 10 days . Bacterial concentration suggested an antimicrobial activity of the implant, but not a full sterilisation of the osteomyelitis . CONCLUSION: Norden's experimental osteomyelitis model with rabbit was proposed to assess the therapeutic activity of systemic antibiotics, but not to evaluate biomaterials . Therefore we have shifted for experimental evaluation of biomaterials to a metaphyseal osteomyelitis in the sheep, the patterns of which are close from those of the human disease. J Am Acad Dermatol, 1999 Jan, 40(1), 77 - 84 Prophylactic antibiotics in patients undergoing laser resurfacing of the skin; Manuskiatti W et al.; BACKGROUND: Carbon dioxide (CO2) laser resurfacing produces a superficial second-degree burn that needs to be protected from bacterial and fungal infections . OBJECTIVE: We investigated the effects of various systemic and topical antimicrobial regimens . METHODS: Four different regimens using oral ciprofloxacin, topical antibiotics (intranasal mupirocin ointment and otic solution), oral ketoconazole, and oral fluconazole were tested in four time periods . The frequency and types of the infections with various regimens was compared . RESULTS: The study included 356 sequential patients who underwent facial CO2 laser resurfacing . Infections occurred in 27 patients (7.6%) . Without antibiotic prophylaxis, 8.2% of patients had bacterial infections from days 3 to 12 after the procedure (average, day 5) . With prophylactic ciprofloxacin only, 4.3% of patients had bacterial infections; these occurred almost exclusively after ciprofloxacin was discontinued . For 7 months, patients were randomly assigned to either receive or not receive mupirocin intranasally . All Staphylococcus aureus infections that occurred were seen in patients who had used intranasal mupirocin . Yeast infections were seen in 6 patients (1.7%), but mostly occurred more than 10 days after the procedure . Yeast infections were of approximately equal occurrence in the ciprofloxacin group (2.2%) and in the non-ciprofloxacin group (1.8%) . No yeast infections occurred in patients who had undergone antifungal prophylaxis . CONCLUSIO