J Ind Microbiol Biotechnol, 2003 Feb, 30(2), 102 - 6 Epub 2003 Jan 14. Antimicrobial efficacy of a silver-zeolite matrix coating on stainless steel; Cowan MM et al.; A silver- and zinc-containing zeolite matrix (AgION) used as a coating for stainless steel was tested for antimicrobial efficacy against Escherichia coli 25922, Staphylococcus aureus 25923, Pseudomonas aeruginosa 27853, and Listeria monocytogenes 7644 . Assays were performed on flat coupon surfaces and in formed steel cups . AgION reduced microbial colony-forming units when compared to uncoated steel surfaces under all conditions tested . Percent reductions ranged from 84.536 to 99.999 after 4 h exposure, and from 99.992 to 100 after 24 h in all cases . The durability of the coatings declined most markedly when the coating had been applied with a wet process and scrubbed between uses with a test tube brush . Powder-coated surfaces cleaned with a towel retained a high degree of activity after five cycles of use. Ann Med Interne (Paris), 2002 Dec, 153(8), 537 - 9 {Cutaneous and osteoarticular Scedosporium apiospermum infection}; Fays S et al.; Scedosporium apiospermum is a widely distributed fungus that can be found in the soil, manure and decaying vegetation . Human infection with this fungus is facilited by immunodepression . A 65-year-old man, who was taking oral methylprednisolone for rheumatoid polyarthritis had for a few months ulcerated or suppurative nodules whose incision discharged a thick honey-colored exudate . An ulceration over the first right metatarsophalangian articulation had left the bone exposed . The treatment for Pseudomonas aeruginosa, initially isolated in the exudate was unsuccessful . Other microbiology samples exhibited Scedosporium apiospermum, without bacteria . The pathogenic nature of the infection was proven on a skin and bone (head of the first metatarsian) biopsy showing numerous branching and septate hyphae . The patient was successfully treated by itraconazole . Scedosporium apiospermum is the cause of a growing number of human infections due to widespread use of immunosuppressors . Skin and lung localizations predominate . Osteoarticular infection is relatively rare, which contributes to the originality of this observation . Treatment is not well defined and essentially combines surgical drainage with antifungals like itraconazole . This emergent fungal infection, which has non specific clinical manifestations, must be considered in immunocompromised patients. Biophys J, 2003 Mar, 84(3), 1765 - 72 Molecular basis for microbial adhesion to geochemical surfaces: computer simulation of Pseudomonas aeruginosa adhesion to goethite; Shroll RM et al.; The adhesion of Pseudomonas aeruginosa to the goethite mineral is investigated using classical molecular simulation . A fragment model for goethite has been integrated into a fully atomistic membrane model . Properties for the resulting system are evaluated for a 1.5-ns simulation in the isothermal-isobaric ensemble . The response of the membrane to the presence of the mineral is investigated . Radial distribution functions are used to present an average picture of the hydrogen bonding . Orientational vectors, assigned to the saccharide groups, reveal the extent of the mineral's perturbations on the membrane . Significant structural changes were observed for the outermost saccharide groups, several of which rotate to form hydrogen bonds with the mineral surface . The structure of the inner core, and the corresponding integrity of the membrane, is maintained . The mineral surface dehydrates slightly in the presence of the membrane as saccharide hydroxyl groups compete with water molecules for hydrogen-bonding sites on its surface. FEBS Lett, 2003 Feb 27, 537(1-3), 182 - 6 Analytical model for determination of parameters of helical structures in solution by small angle scattering: comparison of RecA structures by SANS; Lebedev DV et al.; The filament structures of the self-polymers of RecA proteins from Escherichia coli and Pseudomonas aeruginosa, their complexes with ATPgammaS, phage M13 single-stranded DNA (ssDNA) and the tertiary complexes RecA::ATPgammaS::ssDNA were compared by small angle neutron scattering . A model was developed that allowed for an analytical solution for small angle scattering on a long helical filament, making it possible to obtain the helical pitch and the mean diameter of the protein filament from the scattering curves . The results suggest that the structure of the filaments formed by these two RecA proteins, and particularly their complexes with ATPgammaS, is conservative. Cornea, 2003 Mar, 22(2), 131 - 4 Phenotype of Pseudomonas aeruginosa isolates causing corneal infection between 1997 and 2000; Cowell BA et al.; PURPOSE: To investigate the relationship between functional phenotype of and the associated human corneal infection . METHODS: This was an experimental pilot study of patients presenting with corneal infections at the Jules Stein Eye Institute with presumed infection during the period from 12/30/97 to 9/1/00 . Thirteen patients were admitted to the study based on positive identification of the causative pathogen as and patient consent . Data were collected (including bacterial cultures, lens wear schedule and care, gender and age, completed history questionnaire, clinical photographs) . Statistical analysis of possible correlations was performed . Phenotypes of were determined, and clinical factors associated with infection were explored . RESULTS: Both invasive and cytotoxic phenotypes of were isolated in equal proportion . Cytotoxic strains and invasive strains were found to be associated with patients younger than 50 years of age and older than 50 years of age, respectively . CONCLUSIONS: remains a significant pathogen in corneal infection, especially during contact lens wear . The age of the patient may influence the phenotype of causing infection . Since invasive and cytotoxic strains have different effects on corneal cells, treatment of the infection might require different approaches depending on this phenotype of the causative bacteria. Antimicrob Agents Chemother, 2003 Mar, 47(3), 1140 - 2 Postantibiotic effects of garenoxacin (BMS-284756) against 12 gram-positive or -negative organisms; Pankuch GA et al.; Conventional in vitro methods were used to determine the postantibiotic effects (PAEs), sub-MIC effects (SMEs), and postantibiotic sub-MIC effects (PA-SMEs) of garenoxacin for a range of organisms . The mean PAEs of garenoxacin for pneumococci, staphylococci, and enterococci were 0.3 to 2.2 h . For Escherichia coli and Pseudomonas aeruginosa, the PAEs were 0.9 to 1.6 h . The mean PA-SMEs (0.4 times the MIC) for pneumococci, staphylococci, and enterococci were 3.0 to >10 h, 1.8 to >10.7 h, and 5.8 h, respectively, while those for E . coli and P . aeruginosa were 7.6 and 4.4 h, respectively. Antimicrob Agents Chemother, 2003 Mar, 47(3), 1101 - 11 Aminoglycoside efflux in Pseudomonas aeruginosa: involvement of novel outer membrane proteins; Jo JT et al.; The expression of tripartite multidrug efflux pumps such as MexA-MexB-OprM in Pseudomonas aeruginosa contributes to intrinsic resistance to a wide variety of antimicrobials, including beta-lactams, chloramphenicol, macrolides, quinolones, and tetracycline . The MexX-MexY linker-pump combination has been shown to be involved in intrinsic resistance to aminoglycosides, but the identity of the cognate outer membrane channel component remains under debate . Fourteen uncharacterized OprM homologs identified in the genome of P . aeruginosa were examined as candidates for this role by assessing the minimum inhibitory concentrations (MICs) of aminoglycosides in P . aeruginosa strain PAK knockout mutants lacking the corresponding genes . Insertional inactivation of OpmG, OpmI, and OpmH resulted in decreases of various degrees in the MICs of streptomycin, kanamycin, and gentamicin . When reintroduced into P . aeruginosa on multicopy plasmids, OpmG was able to complement the susceptibility of an opmG::miniTn5 mutant; however, cloned opmH, the proposed ortholog of Escherichia coli tolC according to our phylogenetic analysis, was able to only partially complement the opmH::miniTn5 mutant . Mini-microarray hybridization analysis demonstrated that opmG disruption does not affect expression of OpmI or OpmH (ruling out such indirect effects on aminoglycoside resistance); however, opmH disruption did have possible effects on expression of OpmG and OpmI . Based on the data, we propose that OpmG is a major outer membrane efflux channel involved in aminoglycoside efflux in P . aeruginosa PAK and that OpmI, its most related paralog, may share an overlapping function. Antimicrob Agents Chemother, 2003 Mar, 47(3), 972 - 8 Efflux-mediated resistance to tigecycline (GAR-936) in Pseudomonas aeruginosa PAO1; Dean CR et al.; Pseudomonas aeruginosa strains are less susceptible to tigecycline (previously GAR-936; MIC, 8 micro g/ml) than many other bacteria (P . J . Petersen, N . V . Jacobus, W . J . Weiss, P . E . Sum, and R . T . Testa, Antimicrob . Agents Chemother . 43:738-744, 1999) . To elucidate the mechanism of resistance to tigecycline, P . aeruginosa PAO1 strains defective in the MexAB-OprM and/or MexXY (OprM) efflux pumps were tested for susceptibility to tigecycline . Increased susceptibility to tigecycline (MIC, 0.5 to 1 micro g/ml) was specifically associated with loss of MexXY . Transcription of mexX and mexY was also responsive to exposure of cells to tigecycline . To test for the emergence of compensatory efflux pumps in the absence of MexXY-OprM, mutants lacking MexXY-OprM were plated on medium containing tigecycline at 4 or 6 micro g/ml . Resistant mutants were readily recovered, and these also had decreased susceptibility to several other antibiotics, suggesting efflux pump recruitment . One representative carbenicillin-resistant strain overexpressed OprM, the outer membrane channel component of the MexAB-OprM efflux pump . The mexAB-oprM repressor gene, mexR, from this strain contained a 15-bp in-frame deletion . Two representative chloramphenicol-resistant strains showed expression of an outer membrane protein slightly larger than OprM . The mexCD-OprJ repressor gene, nfxB, from these mutants contained a 327-bp in-frame deletion and an IS element insertion, respectively . Together, these data indicated drug efflux mediated by MexCD-OprJ . The MICs of the narrower-spectrum semisynthetic tetracyclines doxycycline and minocycline increased more substantially than did those of tigecycline and other glycylcyclines against the MexAB-OprM- and MexCD-OprJ-overexpressing mutant strains . This suggests that glycylcyclines, although they are subject to efflux from P . aeruginosa, are generally inferior substrates for P . aeruginosa efflux pumps than are narrower-spectrum tetracyclines. Biochem Biophys Res Commun, 2003 Mar 7, 302(2), 363 - 71 Chromosomal organization and transcription analysis of genes in the vicinity of Pseudomonas aeruginosa glmM gene encoding phosphoglucosamine mutase; Tavares IM et al.; A computer-aided analysis of the Pseudomonas aeruginosa PAO1 genome surrounding the glmM gene was carried out and the organization of this chromosomal region was compared with the equivalent regions in other gamma-proteobacteria species with the genome sequence available . glmM encodes the enzyme phosphoglucosamine mutase which catalyses the interconversion of glucosamine-6-phosphate into glucosamine-1-phosphate in the biosynthetic pathway leading to the synthesis of UDP-N-acetylglucosamine which is simultaneously a precursor for the biosynthesis of cell-wall peptidoglycan and outer membrane lipopolysaccharide . Northern blot analysis suggests that glmM may be a part of the five-cistron operonic structure composed by the Escherichia coli homologues ftsJ, ftsH, folP, glmM, and tpiA . The secG gene, downstream tpiA, does not make part of this polygenic organization, being actively transcribed as a monocistronic mRNA during transition to the stationary phase of growth . Differently, transcription of genes in the glmM operon is more active in the early exponential phase, decreasing with the increase of cell density during exponential growth and reaching negligible values in stationary phase cells. Chem Biol Interact, 2003 Feb 1, 143-144, 149 - 58 Inactivation of betaine aldehyde dehydrogenase from Pseudomonas aeruginosa and Amaranthus hypochondriacus L . leaves by disulfiram; Velasco-Garcia R et al.; Betaine aldehyde dehydrogenase (BADH) activity might be crucial for the growth of the human pathogen Pseudomonas aeruginosa under conditions of infection and therefore appears to be a suitable target for antimicrobial agents . As a first step in the search for BADH inhibitors, we have tested the effects of the known aldehyde dehydrogenase inhibitor disulfiram (DSF) on the activity of P . aeruginosa and Amaranthus hypochondriacus (amaranth) leaf BADHs . DSF totally inactivated both enzymes in a time- and dose-dependent manner . In the case of the Pseudomonas enzyme, inactivation kinetics were monophasic with a second-order inactivation rate constant at pH 6.9 of 4.9+/-0.4 M(-1) s(-1), whereas the plant enzyme was inactivated in a biphasic process with second-order inactivation rate constants at pH 7.5 of 6.8+/-0.6 and 0.33+/-0.04 M(-1) s(-1) . At pH 8.8, the second-order rate constants for inactivation of the bacterial enzyme was 1 x 10(3) M(-1) s(-1), which compare well with that reported for human liver mitochondrial aldehyde dehydrogenase (ALDH2), the target of DSF inhibition in the aversion therapy of alcoholism . Both BADHs were inactivated faster in the presence of NAD(P)(+) than in its absence, whereas NAD(P)H and betaine aldehyde protected the bacterial, but increased the inactivation rate of the plant enzyme . The inactivated enzymes were reactivated by dithiothreitol, but not by a high concentration of the physiological reductant glutathione . The high in vitro sensitivity of the Pseudomonas BADH to DSF, particularly in the presence of NAD(P)(+), together with the lack of reversibility of DSF modification by glutathione, makes this inhibitor a potential antimicrobial agent and suggests that it might be worth testing its effects and those of its metabolites in vivo, under culture conditions in which the activity of BADH is required for growth of the bacteria. Chem Biol Interact, 2003 Feb 1, 143-144, 139 - 48 Monovalent cations requirements for the stability of betaine aldehyde dehydrogenase from Pseudomonas aeruginosa, porcine kidney and amaranth leaves; Valenzuela-Soto EM et al.; Betaine aldehyde dehydrogenase from the human pathogen Pseudomonas aeruginosa requires K(+) ions for maintenance of its active conformation . In order to explore if this property is shared by other BADHs of different origins and to further understand the mechanism underlying the effects of these ions, we carried out a comparative study on the stability and quaternary structure of P . aeruginosa, porcine kidney and amaranth leaves BADHs in the absence of K(+) ions . At low enzyme concentrations, the bacterial and porcine enzymes were totally inactivated upon removal of K(+) following biphasic and monophasic kinetics, respectively, whereas the amaranth enzyme retained its activity . Inactivation of P . aeruginosa BADH was much faster than that of the porcine enzyme . The oxidized coenzyme protected both enzymes against inactivation by the absence of K(+), whereas betaine aldehyde afforded partial protection to the bacterial BADH and increased the inactivation rate of the porcine . Reactivation of the inactive enzymes, by adding back to the incubation medium K(+) ions, was dependent on enzyme concentration, suggesting that enzyme dissociation takes place in the absence of K(+) . In the bacterial enzyme, NH(4)(+) but not Na(+) ions could mimic the effects of K(+), whereas the three cations tested reactivated porcine BADH, indicating a requirement of this enzyme for high ionic strength rather than for a specific monovalent cation . Size exclusion chromatography of the inactivated enzymes confirmed that K(+) ions or other monovalent cations are required for the maintenance of the quaternary structure of these two BADHs . At pH 7.0, in the absence of K(+) in a buffer of low ionic strength, the active tetrameric form of P . aeruginosa BADH dissociated into inactive monomers and that of porcine kidney BADH into inactive dimers . Once reactivated, both enzymes reassociated into active tetramers. Chem Biol Interact, 2003 Feb 1, 143-144, 129 - 37 Ligand-induced conformational changes of betaine aldehyde dehydrogenase from Pseudomonas aeruginosa and Amaranthus hypochondriacus L . leaves affecting the reactivity of the catalytic thiol; Munoz-Clares RA et al.; The reaction catalyzed by betaine aldehyde dehydrogenase (BADH) involves the nucleophilic attack of a catalytic cysteinyl residue on the aldehyde substrate . As a possible mechanism of regulation, we have studied the modulation by ligands of the reactivity and/or accessibility of the essential thiol of the enzyme from the human pathogen Pseudomonas aeruginosa and the leaves of the plant Amaranthus hypochondriacus (amaranth) . In the absence of ligands, the kinetics of inactivation by thiol modifying reagents of both enzymes were biphasic, suggesting the existence of two enzyme conformers differing in the reactivity of their catalytic thiolate . Preincubation of P . aeruginosa BADH with the coenzymes or the aldehyde prior to the chemical modification brought about active site rearrangements that resulted in an important decrease in the inactivation rate . Amaranth BADH responded similarly to the preincubation with NADH or betaine aldehyde but NAD(+) elicited opposite changes, increasing the rate of inactivation after prolonged preincubation . In amaranth BADH, the different behavior of both coenzymes, and the observed biphasic inactivation kinetics are consistent with the previously proposed iso kinetic mechanism, characterized by the existence of two interconvertible apoenzyme forms, one able to bind NAD(+) and the other NADH . Taken together, our results suggest that ligand-induced conformational changes in BADH from the two sources studied might be important for both proper enzyme function and protection against oxidation. J Liposome Res, 2002, 12(3), 239 - 57 Effects of Cl2MDP-encapsulating liposomes in a murine model of Pseudomonas aeruginosa-induced sepsis; Fujimoto J et al.; Pseudomonas aeruginosa is a pathogen that frequently causes acute lung injury, bacteremia and sepsis in critically ill patients . As tissue macrophages are a major producer of inflammatory mediators that contribute to septic physiology, and are essential for eliminating bacteria from the circulation, we investigated the role of tissue macrophages in the generation of both inflammatory and anti-inflammatory cytokines in septic shock by using our mouse model of P . aeruginosa pneumonia . To see the effects of tissue macrophage depletion, we intravenously injected dichloromethylene-diphosphonate (Cl2MDP)-encapsulating liposomes in mice . Two days after the liposome injection, we instilled cytotoxic P . aeruginosa (PA103) into the lung that disseminates and causes septic shock . After the infection, we collected blood and bronchoalveolar lavage fluids . The samples were then analyzed for TNF-alpha, MIP-2, and IL-10 concentration . We compared these results to control mice that received either liposomes without Cl2MDP or phosphate buffered saline alone . Plasma TNF-alpha, MIP-2, and IL-10 levels were significantly decreased in the tissue macrophage-depleted mice compared to the control groups of mice . Although depletion of tissue macrophages by Cl2MDP-liposome administration did not affect the severity of bacteremia or the survival of infected mice, these results imply that tissue macrophages have a major role in the production of both proinflammatory and anti-inflammatory cytokines in the circulation and in the causing septic physiology associated with P . aeruginosa pneumonia. East Mediterr Health J, 2001 Jan-Mar, 7(1-2), 38 - 45 Etiology of toe-web disease in Al-Ain, United Arab Emirates: bacteriological and mycological studies; Lestringant GG et al.; We examined and sampled 45 patients with toe-web intertrigo for bacteriological and mycological studies . Prominent isolated pathogens were the genus Candida (57.7%), genus Aspergillus (28.8%), Pseudomonas aeruginosa (26.7%) and coliforms (24.4%) . Dermatophytes scored 4.4% (Trichophyton rubrum) . There were 43 patents (95.5%) who presented with marked hyperkeratosis and maceration of the toe-webs involved . The tradition of the Emirati population of sitting cross-legged may, over time, induce in the toe-webs of overweight individuals a macerated pressure-reaction hyperkeratosis that is colonized by environmental germs . T . rubrum and T . mentagrophytes are uncommon in the Al-Ain environment and this may explain the rarity of dermatophytes in toe-web intertrigo in our study. J Basic Microbiol, 2003, 43(1), 36 - 46 Identification of a major protein upon phosphate starvation of Pseudomonas aeruginosa PAO1; Madhusudhan KT et al.; To understand the physiology of non-differentiating bacteria exposed to nutrient deprivation and stress, various approaches have been employed in combination with detailed analysis of protein synthesis pattern . In this study, separation of proteins from clarified cell extracts of Pseudomonas aeruginosa PAO1 grown under phosphorus limiting conditions was achieved by high resolution two-dimensional gel electrophoresis (2-DE) . Limitation of phosphate in the growth medium revealed significant differences in the 2-DE pattern of proteins between phosphate starved cells and an unstarved control . A major protein identified as PstS, a phosphate binding protein of the pts operon was exclusively found on 2-DE gels of phosphate starved bacteria . The identity of protein was established based on the results of Edman degradation, amino acid analysis and mass spectrometry . PstS was also found in other pseudomonads, and therefore, it can be used as a landmark protein in proteomic studies . Additionally, we propose utilizing pstS of pseudomonads for testing bioavailable phosphate from soils and water streams. Infect Immun, 2003 Mar, 71(3), 1590 - 5 DsbA of Pseudomonas aeruginosa is essential for multiple virulence factors; Ha UH et al.; DsbA is a periplasmic thiol:disulfide oxidoreductase which contributes to the process of protein folding by catalyzing the formation of disulfide bonds . In this study, we demonstrate that the dsbA gene is required for the expression of the type III secretion system under low-calcium inducing conditions, intracellular survival of P . aeruginosa upon infection of HeLa cells, and twitching motility . The diverse phenotypes of the dsbA mutant are likely due to its defect in the folding of proteins that are involved in various biological processes, such as signal sensing, protein secretion, and defense against host clearing . In light of its effect on various virulence factors, DsbA could be an important target for the control of P . aeruginosa infections. Infect Immun, 2003 Mar, 71(3), 1453 - 61 Protection against fatal Pseudomonas aeruginosa pneumonia in mice after nasal immunization with a live, attenuated aroA deletion mutant; Priebe GP et al.; Studies of immunity to Pseudomonas aeruginosa have indicated that a variety of potential immunogens can elicit protection in animal models, utilizing both antibody- and cell-mediated immune effectors for protection . To attempt to optimize delivery of multiple protective antigens and elicit a broad range of immune effectors, we produced an aroA deletion mutant of the P . aeruginosa serogroup O2/O5 strain PAO1, designated PAO1deltaaroA . Previously, we reported that this strain elicits high levels of opsonic antibody directed against many serogroup O2/O5 strains after nasal immunization of mice and rabbits . Here, we assessed the protective efficacy of immunization with PAO1deltaaroA against acute fatal pneumonia in mice . After active immunization, high levels of protection were achieved against an ExoU-expressing cytotoxic variant of the parental strain PAO1 at doses up to 1,000-fold greater than the 50% lethal dose . Significant protection against PAO1 and two of four other serogroup O2/O5 strains was also found, but there was no protection against serogroup-heterologous strains . The serogroup O2/O5 strains not protected against were killed in opsonophagocytic assays as efficiently as the strains with which protection was seen, indicating a lack of correlation of protection and opsonic killing within the serogroup . In passive immunization experiments using challenge with wild-type PAO1 or other noncytotoxic members of the O2/O5 serogroup, there was no protection despite the presence of high levels of opsonic antibody in the mouse sera . However, passive immunization did prevent mortality from pneumonia due to the cytotoxic PAO1 variant at low-challenge doses . These data suggest that a combination of humoral and cellular immunity is required for protection against P . aeruginosa lung infections, that such immunity can be elicited by using aroA deletion mutants, and that a multivalent P . aeruginosa vaccine composed of aroA deletion mutants of multiple serogroups holds significant promise. Infect Immun, 2003 Mar, 71(3), 1328 - 36 Experimental Pseudomonas aeruginosa keratitis in interleukin-10 gene knockout mice; Cole N et al.; Pseudomonas aeruginosa keratitis is one of the most destructive diseases of the cornea . The host response to this infection is critical to the outcome . The cytokine interleukin-10 (IL-10) is thought to play an important role in modulating excessive inflammation and antimicrobial defenses . We have found that in IL-10(-/-) mice there is a significant decrease in bacterial load in corneas at 7 days postchallenge with P . aeruginosa . This decrease was accompanied by a reduction in neutrophil numbers in the cornea and changes in cytokine levels compared to those of wild-type mice . A characteristic increase in neovascularization in the cornea was found in the IL-10(-/-) mice . This increased angiogenesis correlated with an increased expression of KC, whereas the kinetics of macrophage inflammatory peptide 2 expression correlated with neutrophil numbers . This finding suggests that KC may play a role in corneal angiogenesis . The source of IL-10 in mouse corneas was identified as a subpopulation of infiltrating cells and keratocytes . This study demonstrates that IL-10 plays an important role in regulating the balance of inflammatory mediators during P . aeruginosa infection of the cornea. Surg Infect (Larchmt), 2000, 1(1), 65 - 72 The role of quinolones in abdominal surgery; Nichols RL; The quinolone antibiotics have been a major advance for the treatment of various types of infections . These agents have generally good safety profiles, broad-spectrum activity, and favorable pharmacokinetics . In addition, several of these antibiotics are available in both intravenous and oral formulations, which allows for sequential therapy resulting in potential cost savings . However, patients can develop serious central nervous system side effects (seizures) and phototoxicity . In addition, the bioavailability of agents in this class can be reduced by coadministration with cations, such as magnesium, aluminum, calcium, and iron, which may make bioavailability unpredictable in patients . Although older quinolones such as ciprofloxacin were effective as prophylactic agents for biliary procedures and colorectal surgery and for the treatment of intra-abdominal infections, the use of these older quinolones was limited by the development of resistant organisms . In addition, because these agents had poor activity against anaerobes such as Bacteroides fragilis, the agents had to be combined with an antianaerobic agent, such as metronidazole, when anaerobic coverage was required . Recently, a new quinolone, trovafloxacin, has become available . Trovafloxacin has demonstrated increased activity against anaerobes in animal and human studies . However, the clinical profile of trovafloxacin for abdominal infections has not been fully demonstrated, and there is some concern that its activity against aerobic gram-negative bacilli, especially Pseudomonas aeruginosa, may not equal that of ciprofloxacin . Moreover, the safety profile of trovafloxacin is disadvantageous owing to reports of severe hepatic toxicity. Microbes Infect, 2003 Jan, 5(1), 27 - 30 Antineutrophil cytoplasmic antibodies directed against bactericidal/permeability-increasing protein detected in children with cystic fibrosis inhibit neutrophil-mediated killing of Pseudomonas aeruginosa; Sediva A et al.; Antineutrophil cytoplasmic antibodies (ANCA) directed against bactericidal/permeability-increasing protein (BPI) were repeatedly found in cystic fibrosis (CF) patients . We analyzed the effect of BPI-ANCA in inhibiting neutrophil-mediated killing of Pseudomonas aeruginosa . The bactericidal effect expressed as percentage of killed bacteria after 1 h incubation with neutrophils was 55% when the neutrophils were pretreated with normal human serum, ranged from 49 to 63% with the sera from control BPI-ANCA-negative groups and sharply decreased to the mean 30.5% (range 8-51%) in the presence of BPI-ANCA . Furthermore, the effect mediated by BPI-ANCA was dose dependent and reflected the titer of BPI-ANCA in tested sera. Surg Infect (Larchmt), 2002 Spring, 3(1), 29 - 33 Mycotic aneurysm of the descending thoracic aorta caused by Pseudomonas aeruginosa in a solid organ transplant recipient: case report and review; Feltis BA et al.; BACKGROUND: Pseudomonas aeruginosa is a rare cause of aortic mycotic aneurysms . Optimal treatment, including reconstructive graft material and appropriate length of antibiotic therapy, is being debated . METHODS: We describe a 26-year-old kidney-pancreas recipient who developed an aneurysm of the descending thoracic aorta caused by P . aeruginosa . RESULTS: After surgical debridement and cryopreserved allograft reconstruction, parenteral antibiotics were continued for 12 months, at which time the patient was converted to oral antibiotic therapy . Within 6 months, he redeveloped a thoracic aortic aneurysm, necessitating reoperation and lifelong parenteral antibiotic therapy . CONCLUSION: Herein we review and discuss the relevant literature concerning surgical and antibiotic treatment of mycotic thoracic aneurysms. Indian J Pathol Microbiol, 2002 Jan, 45(1), 15 - 22 Study of fungal and bacterial infections of the diabetic foot; Chincholikar DA et al.; Microbiological study for aerobic organisms, anaerobic organisms and fungi from 105 cases of diabetic foot ulcers was carried out to determine the aetiological agents and their antibiograms . Out of 265 microbial isolates obtained, 160 were aerobes, 50 anaerobes and 55 fungal strains . Polymicrobial infection was observed in 73 (69.5%) cases . The most frequently isolated aerobic microorganisms were Staphylococcus aureus and Pseudomonas aeruginosa . Among the anaerobes Bacteroides melaninogenicus and Bacteroides fragilis were most common . Candida species were preponderant among the fungal isolates . Antimicrobial sensitivity pattern of the isolates is discussed in detail. Clin Microbiol Infect, 2003 Feb, 9(2), 101 - 9 Infecton: a 99mTc-ciprofloxacin radiopharmaceutical for the detection of bone infection; Malamitsi J et al.; OBJECTIVE: To evaluate Infecton scintigraphy, with technetium-99m-radiolabeled ciprofloxacin, as a means to detect bone infection, in comparison with other conventional scintigraphic and radiologic methods . METHODS: Forty-five patients with known or suspected bone infection underwent 50 scans with Infecton . Almost all were also subjected to a three-phase 99mTc-methylene diphosphonate bone scan and most of them to a 99mTc-human polyclonal immunoglobulin scan as well as to a gallium-67-citrate scan, plus computerized tomography or magnetic resonance imaging or both . Clinical laboratory criteria for the presence of osteomyelitis were based on the definitions of the Centers for Disease Control and Prevention . RESULTS: Staphylococcus aureus and Pseudomonas aeruginosa were the most frequently isolated pathogens . Based on the CDC clinical laboratory criteria as well as on conventional scan results, Infecton was characterized in 35 studies as 'true positive', in eight as 'true negative', in two as 'false positive', in one as 'false negative', and in four as 'indeterminate' . The sensitivity and specificity of Infecton scintigraphy were found to be 97.2% and 80%, respectively, with positive and negative predictive values of 94.6% and 88.9% . CONCLUSIONS: It is concluded that Infecton is a very sensitive and quite specific marker of bone infection, but care must be taken in cases of excessive new bone formation and primary bone tumors, where false-positive results may be obtained. Ulus Travma Derg, 2003 Jan, 9(1), 34 - 6 {Evaluation of severe burns managed in intensive care unit}; Kurtoulu M et al.; BACKGROUND: This study designed to evaluate the results of the patients with severe burns treated in the intensive care unit . METHODS: Between May 1997 and May 2002, fifty-four patients who had thermal and electrical burns managed at the Intensive Care Unit of General Surgery of Istanbul University Medical Faculty . RESULTS: Forty-five of patients were males and nine were females with mean age of 39 years . The mean hospital stay was 26 days . The mean total body surface area burns was 60% . Pseudomonas aeruginosa was detected in wound cultures at the 68% of patients . 83% of cases died . Mortality was due to sepsis in 66% of patients . CONCLUSION: Besides early debridmant, early enteral feeding, woundcare and intensive care unit support, establishing of specific burncenters may reduce morbidity and mortality rates in severe burns. Int Immunopharmacol, 2003 Feb, 3(2), 247 - 56 A Limulus anti-LPS factor-derived peptide modulates cytokine gene expression and promotes resolution of bacterial acute infection in mice; Vallespi MG et al.; Sepsis in experimental animals and humans has been associated with perturbed immune response . A major event contributing to the decrease in immune functions in septic disorders seems to be the inadequate balance of cytokines mediating the interactions between the innate and adaptive immune systems . We previously observed that a cyclic peptide derived from the Limulus anti-LPS factor (LALF), which partially protect mice from endotoxic shock lethality, has the ability to modulate cytokine secretion in vitro . We herein examined the effects of the LALF(31-52) peptide in an experimental model of Gram-negative peritoneal sepsis and analyzed the cytokine gene expression in the spleen and liver of peptide-treated mice . The prophylactic administration of LALF(31-52) abrogated the systemic TNF-alpha response, reduced organ damage and increased the survival of infected mice . Histological examination of spleen and liver in peptide-treated mice showed prevention of tissue damage induced by the high dose of Pseudomonas aeruginosa . This treatment modulates the cytokine gene expression in these tissues, stimulating IL-2, IL-12 and IL-13 mRNA synthesis, while IL-4 and IL-10 mRNA expression was not modified . This cytokine profile induced by the LALF-derived peptide seems to be favorable for host resistance against Gram-negative bacteria acute infection . In addition, peptide treatment was effective after the initiation of the systemic inflammatory response, promoting a significant increase in mice survival . These results further demonstrate the immunomodulatory potential of LALF(31-52) and are relevant for the design of prophylactic and therapeutic strategies for acute bacteria infection and sepsis, especially for preventing or ameliorating host immunity defects in these disorders . Dev Cell, 2003 Feb, 4(2), 253 - 63 Coordinate regulation of bacterial virulence genes by a novel adenylate cyclase-dependent signaling pathway; Wolfgang MC et al.; Type III secretion systems (TTSSs) are utilized by numerous bacterial pathogens to inject effector proteins directly into host cells . Using a whole-genome microarray, we investigated the conditions and regulatory factors that control the expression of the Pseudomonas aeruginosa TTSS . The transcriptional response of known TTSS genes indicates a hierarchical pattern of expression in which a set of secretion apparatus and regulatory genes is constitutively expressed . Further analysis of genes coordinately regulated with those encoding the TTSS led to the identification of a signaling pathway that originates from a membrane-associated adenylate cyclase and controls TTSS gene expression . Transcriptome analysis of mutants lacking the ability to synthesize cAMP or the cAMP binding protein Vfr implicated this pathway in the global regulation of host-directed virulence determinants, including the TTSS. Yao Xue Xue Bao, 2001 Jun, 36(6), 419 - 22 {Synthesis and antibacterial activity of 5-amino-6, 8-difluoro-1-(5-fluoro-2-pyridyl)-7-(3-methyl-1-piperazinyl)-1, 4-dihydro-4-oxo-3-quinolinecarboxylic acid and its analogues}; Liu JY et al.; AIM: To design and synthesize 1-(5-fluoro-2-pyridyl) quinolone derivatives, and to study their in vitro antibacterial activities . METHODS: Eight new compounds of 5-amino-6,8-difluoro-1-(5-fluoro-2-pyridyl)-7-(3-methyl-1-piperazinyl)-1, 4-dihydro-4-oxo-3-quinolinecarboxylic acid and its analogues were synthesized from ethyl 6-nitro-2, 3, 4, 5-terafluorobenzoylacetate and ethyl 3-methoxy-2, 4, 5-trifluorobenzoylacetate through 5 or 6 steps . RESULTS: Fifteen new compounds (1-15) were obtained including 8 desired compounds (8-15) . The structures of the compounds were determined by 1HNMR, MS . CONCLUSION: In vitro antibacterial activities of the compounds (8-15) against Staphylococcus aureus-16, Escherichia coli-26 and Pseudomonas aeruginosa-17 were lower than control of ciprofloxacin. FEMS Microbiol Lett, 2003 Jan 21, 218(1), 85 - 92 Identification of peptide inhibitors of Pseudomonas aeruginosa exotoxin A function using a yeast two-hybrid approach; Thompson C et al.; The yeast two-hybrid system was used to identify peptide inhibitors of exotoxin A of Pseudomonas aeruginosa with the goal of using these to design peptide-based drugs against the toxin . A random peptide library consisting of 10(7) peptides ranging in length from 16 to 63 residues was screened for peptides that interact with the C-domain of exotoxin A . From the 10(7) transformants screened, three unique peptides of 63, 61 and 25 amino acids in length were found to specifically interact with the enzyme domain . The genes encoding these peptides were cloned and expressed as fusion proteins with the maltose-binding protein . In vitro inhibition measurements indicated that two of the peptides were modest inhibitors of toxin enzyme activity . These peptides now provide the basis for the development of more potent inhibitors, which will serve as lead inhibitors for evolution of potent peptide-based therapeutics. FEMS Microbiol Lett, 2003 Jan 21, 218(1), 51 - 7 Optimisation of AP-PCR fingerprinting discriminatory power for clinical isolates of Pseudomonas aeruginosa; Dabrowski W et al.; Recently methods based on analysis of arbitrarily amplified target sites of microorganism genomes have been extensively applied in microbiological studies . The range of their applications is limited by problems with discrimination and reproducibility resulting from lack of standardised and reliable methods of optimisation . By orthogonal-array optimisation most advantageous and optimal parameters for highly discriminatory primers (CagA2+CMVin2) were selected and efficient AP-PCR (arbitrarily primed-polymerase chain reaction) fingerprinting conditions for Pseudomonas aeruginosa isolates were set up . Stable and multiplex amplicon profiles obtained in this study revealed high level of intraspecies DNA polymorphism among 20 analysed clinical strains of P . aeruginosa proving optimised AP-PCR fingerprinting to be useful in epidemiological typing of the species. Intern Med, 2003 Jan, 42(1), 25 - 32 Clinical analysis of patients requiring long-term mechanical ventilation of over three months: ventilator-associated pneumonia as a primary complication; Kobashi Y et al.; OBJECTIVE: To evaluate the clinical features, etiology, and prognosis of patients who required long-term mechanical ventilation (LMV) of over three months for respiratory failure following underlying disease, and observation of their clinical course until death . PATIENTS: Thirty-seven patients (27 males, 10 females) treated in the internal and medical intensive care unit at Kawasaki Medical School Kawasaki Hospital over the 16-year period from April 1985 to March 2001 were retrospectively studied . RESULTS: Many of these patients were elderly males with respiratory disease such as pulmonary emphysema or old pulmonary tuberculosis, which had developed into acute respiratory failure resulting in respiratory tract infection and initiation of mechanical ventilation . The survival rates of one year, three years and five years after the start of mechanical ventilation were 60%, 30%, and 16%, retrospectively, and the prognoses were poor . Respiratory tract infection was the most common and serious complication . Specifically, ventilator-associated pneumonia (VAP) was a complication in 21 patients and also the main-cause of death . VAP was observed 2.3 years after the initiation of mechanical ventilation with significant differences in the following risk factors being observed between VAP (+) and VAP (-) groups: chronic obstructive pulmonary disease, duration of mechanical ventilation, prior antibiotics, aspiration of gastric contents and use of histamine-type II receptor antagonist . The causative pathogens of VAP were Pseudomonas aeruginosa and Staphylococcus aureus, which were frequently isolated from tracheal aspirates . All patients with VAP caused by MRSA died shortly after contracting the infection . CONCLUSIONS: This study has demonstrated that appropriate treatment for respiratory tract infections such as VAP and the prevention of nasocomial infection due to MRSA is of paramount importance for patients requiring long-term mechanical ventilation of over three months. J Chemother, 2002 Dec, 14(6), 579 - 83 The integration of four major determinants of antibiotic action: bactericidal activity, postantibiotic effect, susceptibility, and pharmacokinetics; Li RC et al.; A functional pharmacokinetic/pharmacodynamic (PK/PD) index that could simultaneously describe three controlling PD variables, i.e., bactericidal activity, postantibiotic effect (PAE), and susceptibility, in relation to pharmacokinetics, was designed using an in vitro kinetic model . Tobramycin was tested against one standard and five clinical strains of Pseudomonas aeruginosa . The organisms showed minimum inhibitory concentrations (MICs) ranging between 1 and >1000 microg/ml . The model allowed antibiotic concentrations to be reduced exponentially from initial concentrations at fixed multiples of MIC . Antibiotic removal was performed when the decreasing concentrations hit the MIC of individual strain to provide a wide range of AUC(>MIC) within an identical frame of AUC(>MIC)/MIC (AUIC) values . Viable counts were measured at antibiotic addition and before/after its removal for bactericidal activity and PAE assessments . A linear relationship was observed between PAE and bactericidal rate constants, though the pattern varied among different strains . Characterization of the exposure (AUC(>MIC))-effect relationships using the Emax model revealed that the less susceptible strains displayed lower Emax and higher EC50 for both antimicrobial effects . By employing the AUIC as a common frame of reference, regression analysis showed a significant linear correlation (p < 0.05) between the mean PAE and bactericidal rate data and, thereby simultaneously defining the four contributing factors of the PK/PD system . It appears that the AUIC, by conveying the pharmacokinetic and susceptibility information, could serve as a PK/PD index in bridging the interdependency of PAE and bactericidal activity . More importantly, the collective assessment of these four factors would allow more optimal evaluation of dosage regimens. J Chemother, 2002 Dec, 14(6), 568 - 73 A survey of antimicrobial drug resistance in respiratory tract pathogens, isolated in a northern Italian teaching hospital between 1990 and 1999; Ferrara A et al.; Drug susceptibility test results of respiratory tract pathogens, isolated from patients admitted to the Clinic of Respiratory Diseases of the IRCCS San Matteo Hospital, University of Pavia (Italy) between 1990 and 1999, were retrospectively evaluated . A total of 1366 bacterial isolates were collected, including 499 gram-positive and 867 gram-negative strains . In comparison to methicillin-susceptible Staphylococcus aureus, the methicillin-resistant strains (MRSA) showed high levels of resistance to many selected antibiotics, except for glycopeptides . Resistance rates to beta-lactams were high in both Pseudomonas aeruginosa and in the other gram-negative isolates, while aminoglycoside and ciprofloxacin resistance was less than 20% . Some pathogens became more resistant to selected antimicrobials during the observation period, including staphylococci to methicillin, MRSA to ciprofloxacin, P . aeruginosa isolates to imipenem and ciprofloxacin, and the other gram-negative strains to almost all drugs considered, with the exception of cefotaxime and cotrimoxazole. Mol Microbiol, 2003 Feb, 47(4), 1123 - 33 The dual roles of AlgG in C-5-epimerization and secretion of alginate polymers in Pseudomonas aeruginosa; Jain S et al.; Pseudomonas aeruginosa strains causing chronic pulmonary infections in cystic fibrosis patients produce high levels of alginate, an exopolysaccharide that confers a mucoid phenotype . Alginate is a linear polymer of d-mannuronate (M) and variable amounts of its C-5-epimer, l-guluronate (G) . AlgG is a periplasmic C-5-epimerase that converts poly d-mannuronate to the mixed M+G sequence of alginate . To understand better the role and mechanism of AlgG activity, a mutant was constructed in the mucoid strain FRD1 with a defined non-polar deletion of algG . Instead of producing poly mannuronate, the algG deletion mutant secreted dialysable uronic acids, as does a mutant lacking the periplasmic protein AlgK . High levels of unsaturated ends and the nuclear magnetic resonance spectroscopy pattern revealed that the small, secreted uronic acids were the products of extensive polymer digestion by AlgL, a periplasmic alginate lyase co-expressed with AlgG and AlgK . Thus, AlgG is bifunctional with (i) epimerase activity and (ii) a role in protecting alginate from degradation by AlgL during transport through the periplasm . AlgK appears to share the second role . AlgG and AlgK may be part of a periplasmic protein complex, or scaffold, that guides alginate polymers to the outer membrane secretin (AlgE) . To characterize the epimerase activity of AlgG further, the algG4 allele of poly mannuronate-producing FRD462 was shown to encode a protein lacking only the epimerase function . The sequence of algG4 has a Ser-272 to Asn substitution in a serine-threonine-rich and conserved region of AlgG, which revealed a critical residue for C-5-epimerase activity. Mol Microbiol, 2003 Feb, 47(4), 903 - 15 Architecture of a protein central to iron homeostasis: crystal structure and spectroscopic analysis of the ferric uptake regulator; Pohl E et al.; Iron is an essential element for almost all organisms, although an overload of this element results in toxicity because of the formation of hydroxyl radicals . Consequently, most living entities have developed sophisticated mechanisms to control their intracellular iron concentration . In many bacteria, including the opportunistic pathogen Pseudomonas aeruginosa, this task is performed by the ferric uptake regulator (Fur) . Fur controls a wide variety of basic physiological processes including iron uptake systems and the expression of exotoxin A . Here, we present the first crystal structure of Fur from P . aeruginosa in complex with Zn2+ determined at a resolution of 1.8 A . Furthermore, X-ray absorption spectroscopic measurements and microPIXE analysis were performed in order to characterize the distinct zinc and iron binding sites in solution . The combination of these complementary techniques enables us to present a model for the activation and DNA binding of the Fur protein. Proc Natl Acad Sci U S A, 2003 Feb 18, 100(4), 1949 - 54 Epub 2003 Feb 10. Hypersusceptibility of cystic fibrosis mice to chronic Pseudomonas aeruginosa oropharyngeal colonization and lung infection; Coleman FT et al.; No transgenic cystic fibrosis (CF) mouse model developed to date mimics the major clinical phenotype found in humans with CF, chronic Pseudomonas aeruginosa lung infection . In a transgenic CF transmembrane conductance regulator (cftr) mouse colony, we found WT, heterozygous, and homozygous CF mice housed in the same cage became chronically colonized in the oropharynx with environmental P . aeruginosa when the bacterium was present in drinking water . Elimination of P . aeruginosa from drinking water resulted in clearance in most WT and CF heterozygous, but not homozygous mice . For experimental evaluation, a combination of specific animal husbandry techniques and an oral infection route showed cftr(-/-) mice but not WT mice can be chronically colonized by P . aeruginosa with subsequent lung translocation, yielding a pathologic picture indicative of chronic lung infection . In some instances, mucoid isolates of P . aeruginosa were recovered from lungs, indicating conditions were present for conversion to mucoidy . Overexpression of human CFTR in the lungs of WT mice markedly accelerated the clearance rate of P . aeruginosa, demonstrating that lung levels of CFTR play an important role in defense against infection . P . aeruginosa mutants unable to express the surface polysaccharide alginate or the global regulator GacA were deficient in their ability to colonize the mice . CF mice made potent immune responses to P . aeruginosa outer membrane antigens . Overall, we found that under the proper conditions, transgenic CF mice are hypersusceptible to P . aeruginosa colonization and infection and can be used for evaluations of lung pathophysiology, bacterial virulence, and development of therapies aimed at treating CF lung disease. Biochemistry, 2003 Feb 18, 42(6), 1673 - 83 Thiols as classical and slow-binding inhibitors of IMP-1 and other binuclear metallo-beta-lactamases; Siemann S et al.; The inhibitory effect of a variety of thiol compounds on the function of binuclear metallo-beta-lactamases, with a particular focus on IMP-1 from Pseudomonas aeruginosa, has been investigated . Thiol inhibitors, depending on their structural features, fall into two categories, one in which inhibition at neutral pH was instantaneous and the other in which inhibition was time-dependent . While mercaptans with anionic substituents in the vicinity of their SH groups exhibited the former type of inhibition, neutral thiols appear to induce a slow, time-dependent isomerization of the initially formed EI complex to a tighter EI complex . Kinetic parameters describing the latter process were obtained by fitting progress curves of substrate hydrolysis using standard and numerical procedures . The failure of charged thiols to exhibit slow binding is suggested to be due to a rapid isomerization of the initial EI complex . Slow binding in the case of neutral thiols was observed only below pH 8 . Studies on the pH dependence of catalysis by IMP-1 revealed that (i) enzyme inactivation at low pH is a slow process with presumably two groups with a pK(a) of approximately 5.2 in the protein being responsible for the loss of activity, (ii) inhibition by thiols is independent of pH between pH 5 and 9, and (iii) an apparent enhancement of the catalytic activity of IMP-1 by thiols occurs at pH <5 . The last mentioned phenomenon is explained by a model in which mercaptans retard the proton-dependent isomerization of the enzyme . Studies on the thiol-mediated inhibition of the binuclear forms of Bacteroides fragilis (CcrA) and Bacillus cereus (BcII strain 5/B/6) metallo-beta-lactamase have revealed that while CcrA was instantaneously albeit moderately inhibited by mercaptans, BcII mimicked IMP-1 in its interaction with thiols . These differences are proposed to be due partly to the structural divergence of these proteins in the vicinity of Zn2. New Microbiol, 2003 Jan, 26(1), 109 - 14 Typing of Pseudomonas aeruginosa strains in Turkish cystic fibrosis patients; Yagci A et al.; The majority of cystic fibrosis (CF) patients suffer from chronic respiratory infection with the opportunistic bacterial pathogen Pseudomonas aeruginosa . The virulence of P . aeruginosa is associated with the presence of various extracellular factors, like alginate, elastase, alkaline protease which contribute tissue destruction and assist bacterial invasion . Virulence factor production of P . aeruginosa strains isolated from 46 CF patients followed in two cities in Turkey was detected . Strains were compared genotypically by arbitrarily primed PCR . Antimicrobial susceptibilities to 12 antibiotics were determined by broth microdilution method . Evaluation of virulence factor results revealed that 95.8% of the strains were alginate, 71.7% elastase and 52.1% alkaline protease producers . AP-PCR analysis revealed 35 genotypes indicated almost a complete discrepancy among the strains . The most effective drugs were penems and quinolones . Among aminoglycosides amikacin was the most effective one and a high level resistance to beta lactams was observed . Alginate is the most important virulence factor in the chronic colonisation of CF patients with P . aeruginosa . No evidence for cross infection between patients and for relationship between phenotypes and genotypes of the strains was found. Shock, 2003 Feb, 19(2), 113 - 6 Impaired production of interferon-gamma and tumor necrosis factor-alpha but not of interleukin 10 in whole blood of patients with sepsis; Rigato O et al.; It has been demonstrated that lipopolysaccharide (LPS)-induced cytokine response in patients with sepsis differ from the normal host, yet this has not been controlled for the presence of underlying disease . We studied the ability of LPS and killed gram-negative bacteria (GNB) to induce tumor necrosis factor (TNF)-alpha and interleukin (IL) 10, and of phytohemagglutinin (PHA) to induce interferon (IFN)-gamma, in whole blood from patients with sepsis (SP, n = 20), patients with matched underlying disease and without sepsis (control patients, n = 20), and healthy volunteers (HV, n = 20) . LPS-induced TNF-alpha production was lower in SP (median = 638 pg/mL) compared with control patients (4060 pg/mL; P= 0.003), and control patients production was lower compared with HV (5329 pg/mL; P < 0.001) . Pseudomonas aeruginosa-induced TNF-alpha production was lower in SP (1443 pg/mL) than in control patients (7319 pg/mL; P < 0.05), and was not different between control patients and HV (6612 pg/mL; P = 0.6) . IFNy production was lower in SP (948 pg/mL) compared with control patients (5516 pg/mL; P < 0.001), and the control patients production was lower compared with HV (11,282 pg/mL; P < 0.001) . IL-10 production was not different among the three groups . Down-regulation of TNF-alpha production in patients with sepsis, although not restricted to them, was more pronounced with LPS than with GNB . Although the presence of underlying disease may be involved in the regulatory mechanisms of host response, the use of controls with matched underlying diseases provides strong evidence for the septic condition in the down-regulation of inflammatory response in patients with sepsis. J Clin Microbiol, 2003 Feb, 41(2), 822 - 5 Spread of integron-associated VIM-type metallo-beta-lactamase genes among imipenem-nonsusceptible Pseudomonas aeruginosa strains in Greek hospitals; Giakkoupi P et al.; Fifty-eight imipenem-nonsusceptible (MIC >or= 8 microg/ml) Pseudomonas aeruginosa strains isolated during May 2001 in 15 Greek hospitals were studied . Thirty-six isolates derived from nine hospitals carried VIM-type metallo-beta-lactamase genes, as found by PCR . In 34 isolates, bla(VIM) was associated with class 1 integrons of various sizes . DNA sequencing indicated the presence of bla(VIM-2) gene cassettes in a variety of integron structures . Random amplified polymorphic DNA typing suggested diversity of the bla(VIM)-positive strains . Synergy between 2-mercaptoacetic acid and imipenem indicated carbapenemase activity in 26 bla(VIM)-positive strains. Chem Biol, 2003 Jan, 10(1), 1 - 2 Molecular radio jamming: autoinducer analogs; Fast W; Synthesis of an N-acyl-homoserine lactone (N-acyl-HSL) analog library yields agonists and antagonists of the Pseudomonas aeruginosa quorum-sensing system . Active compounds also reveal heterogeneity in the lactone ring binding pockets of N-acyl-HSL-activated transcription factors. Zhong Yao Cai, 1997 Jan, 20(1), 38 - 40 {Preliminary study on the pharmacological action spicatus}; Gai H et al.; In this report the pharmacological action of Spicatus was studied . The results insicated that it had diureric, antibiotic and anti-inflammatory effects, yet had Iittle toxic side-effect . It had significant inhibitory effect on crofon oil-caused mice ear swell . It also had marked diuretic effect in orcinary rats, but had Iittie effect on uric pH the rats . It exhibited certain inhibition of Staphycoloccus aureus, Eschrichia coli and Pseudomonas aeruginosa in vitro . The maximum tolerable dose test in mice showed no marked toxic effect, LD50 > 80 g/kg. Heart Lung, 2003 Jan-Feb, 32(1), 59 - 64 Current management of bronchiectasis: review and 3 case studies; Silverman E et al.; Bronchiectasis is the abnormal, irreversible dilatation of diseased bronchi . Permanently dilated airways, usually in the medium-sized bronchi, are inflamed and often obstructed with thick, purulent secretions . Known causative factors include postinfection bronchial damage, postinhalation injury, hypersensitivity reactions, and congenital airway obstructive disorders . Typical symptoms include sputum overproduction, fever, pleurisy, dyspnea, and chronic cough . Diagnosis involves radiographic studies and pulmonary function testing . Treatment includes oral, aerosolized, or intravenous antibiotic therapy according to the severity of the exacerbation, and mucus clearance by means of bronchial hygiene assistive devices, chest physiotherapy, postural drainage, and high-frequency chest compression . We present a review of bronchiectasis and offer 3 case studies illustrating current management of different presentations, including use of aerosolized antibiotics for patients infected with Pseudomonas aeruginosa . Although an adjunctive program of pulmonary rehabilitation may be useful for patients with bronchiectasis, no confirming studies have been performed to date, and additional research in this area is warranted. Am J Respir Crit Care Med, 2003 Jun 1, 167(11), 1478 - 82 Epub 2003 Jan 31. Role of the quorum-sensing system in experimental pneumonia due to Pseudomonas aeruginosa in rats; Lesprit P et al.; The virulence of Pseudomonas aeruginosa is partly controlled by the las quorum-sensing system . A rat model of acute pneumonia was used to investigate the pathophysiological impact of this system by comparing the virulence of the wild-type virulent laboratory strain PAO1 with that of its lasR-deleted mutant PAOR . In comparison with PAO1, PAOR was avirulent after an instillation of 106 cfu (mortality rates, 72 versus 0%, respectively; p < 0.0001) . A ten-fold higher inoculum slightly increased the mortality rate induced by PAOR (25%), which remained lower than that induced by PAO1 (75%, p = 0.0001) . In addition, with both inocula lung and bronchoalveolar lavage bacterial counts were significantly lower in rats infected with PAOR than with PAO1 (p </= 0.01) . Histopathological analysis showed that PAO1 induced a drastic vascular congestion and neutrophil infiltration of the lungs, whereas lung injury in rats infected with PAOR was mild with predominantly macrophage infiltration . This study adds evidence that the quorum-sensing system has an important role in the pathophysiology of P . aeruginosa pulmonary infection. Int J Biol Macromol, 2003 Jan 15, 31(4-5), 195 - 205 Molecular characterization and properties of (R)-specific enoyl-CoA hydratases from Pseudomonas aeruginosa: metabolic tools for synthesis of polyhydroxyalkanoates via fatty acid beta-oxidation; Tsuge T et al.; The use of (R)-specific enoyl-coenzyme A (CoA) hydratase (PhaJ) provides a powerful tool for polyhydroxyalkanoate (PHA) synthesis from fatty acids or plant oils in recombinant bacteria . PhaJ provides monomer units for PHA synthesis from the fatty acid ss-oxidation cycle . Previously, two phaJ genes (phaJ1(Pa) and phaJ2(Pa)) were identified in Pseudomonas aeruginosa . This report identifies two new phaJ genes (phaJ3(Pa) and phaJ4(Pa)) in P . aeruginosa through a genomic database search . The abilities of the four PhaJ(Pa) proteins and the (R)-3-hydroxyacyl-acyl carrier protein {(R)-3HA-ACP} dehydrases, FabA(Pa) and FabZ(Pa), to supply monomers from enoyl-CoA substrates for PHA synthesis were determined . The presence of either PhaJ1(Pa) or PhaJ4(Pa) in recombinant Escherichia coli led to the high levels of PHA accumulation (as high as 36-41 wt.% in dry cells) consisting of mainly short- (C4-C6) and medium-chain-length (C6-C10) 3HA units, respectively . Furthermore, detailed characterizations of PhaJ1(Pa) and PhaJ4(Pa) were performed using purified samples . Kinetic analysis revealed that only PhaJ4(Pa) exhibits almost constant maximum reaction rates (V(max)) irrespective of the chain length of the substrates . The assay for stereospecific hydration revealed that, unlike PhaJ1(Pa), PhaJ4(Pa) has relatively low (R)-specificity . These hydratases may be very useful as monomer-suppliers for the synthesis of designed PHAs in recombinant bacteria. J Am Chem Soc, 2003 Feb 12, 125(6), 1575 - 86 High-throughput catch-and-release synthesis of oxazoline hydroxamates . Structure-activity relationships in novel inhibitors of Escherichia coli LpxC: in vitro enzyme inhibition and antibacterial properties; Pirrung MC et al.; LpxC is a zinc amidase that catalyses the second step of lipid A biosynthesis in Gram-negative bacteria . Oxazolines incorporating a hydroxamic acid, which is believed to coordinate to the single essential zinc ion, at the 4-position are known inhibitors of this enzyme . Some of these enzyme inhibitors exhibit antibacterial activity through their inhibition of LpxC . We recently developed a method for the synthesis of oxazolines using resin capture and ring-forming release that eliminates traditional purification steps and can be used in high-throughput synthesis . Using our method, oxazoline hydroxamates with diverse 2-substituents were prepared in library form as candidate inhibitors for LpxC . Two conventional methods for oxazoline synthesis were also applied to generate more than 70 compounds . The groups at the 2-position included a wide variety of substituted aromatic rings and a limited selection of alkyl groups . These compounds were screened against wild-type and LpxC inhibitor-sensitive strains of Escherichia coli, as well as wild-type Pseudomonas aeruginosa . Inhibition of the E . coli LpxC enzyme was also investigated . A broad correlation between enzyme inhibitory and antibacterial activity was observed, and novel compounds were discovered that exhibit antibacterial activity but fall outside earlier-known structural classes. Eur Surg Res, 2003 Jan-Feb, 35(1), 35 - 40 Influence of omentectomy on peritoneal defense mechanisms in an experimental model of intra-abdominal infection; Agca B et al.; BACKGROUND/AIM: The omentum has an important role as part of peritoneal defense mechanisms . The aim of this study is to show the bactericidal activity of peritoneal fluid and the role of the omentum as a peritoneal defense mechanism in experimental animals with intra-abdominal infections . METHODS: 40 male Spraque-Dawley rats weighing between 250 and 300 g were used in this study . The rats were randomly divided into four groups consisting of 10 animals . The operative procedures were done under sterile conditions . In group I sham laparotomy was done . In group II, the distal part of the cecum was ligated, and cecum perforation was performed . In group III, total omentectomy was performed after cecal ligation and perforation . In group IV only omentectomy was performed . Baseline and 2- and 4-hour peritoneal fluid samples were taken using a Pasteur pipette during laparotomy under anesthesia . Total peritoneal cells counts, bactericidal activity of peritoneal fluid, and types of phagocytic cells in the peritoneal fluid were assessed . RESULTS: As compared with baseline values, the total peritoneal cell counts were increased at the 2nd and 4th h in all groups (p < 0.05) . A significant increase was observed after 4 h as compared with 2 h in sham laparotomy, cecal ligation+perforation+omentectomy, and omentectomy groups (p < 0.05) . A significant increase in the cell counts after 2 h was found in the other groups when compared to the sham laparotomy group (p = 0.0001) . After 4 h, there was a significant difference between the groups, but especially prominent in the cecum ligation+perforation+omentectomy group (p = 0.0001) . Proliferating colony counts of Escherichia coli and Pseudomonas Aeruginosa decreased after 2 h, and there was no proliferation in the subsequent cultures . It was observed that the macrophage counts significantly increased after 2 and 4 h as compared with baseline in intragroup assessments (p = 0.0001) . In the intergroup assessment, an increase was observed in the macrophage counts at baseline and after 2 and 4 h, and this was significant in the cecal ligation+perforation+omentectomy group (p = 0.0001) . In the omentectomy group, a significant decrease was observed in the macrophage counts between the 2nd and 4th h (p = 0.0001) . CONCLUSION: Removal of the omentum in the presence of intra-abdominal infections causes the peripherally derived macrophages to take over the defensive role of macrophages of peritoneal origin as a compensatory mechanism, thus the peritoneal bactericidal activity against E . COLI, the major pathogen in intra-abdominal infections, does not change after omentectomy . Exp Eye Res, 2003 Feb, 76(2), 221 - 31 Role and regulation of CXC-chemokines in acute experimental keratitis; Xue ML et al.; The aim of this study was to elucidate the expression of chemokines, their role and regulation in bacterial corneal infection using three bacterial strains (Pseudomonas . aeruginosa- invasive, cytotoxic and contact lens induced acute red eye strains) which have been shown to produce three distinct patterns of corneal disease in the mouse . The predominant chemokine expressed in response to all three strains was MIP-2 . Prolonged expression of high levels of MIP-2 was associated with increased severity of corneal inflammation . Significantly reduced disease severity upon administration of anti-MIP-2 antibodies suggested that MIP-2 may play an important role in the pathogenesis of Pseudomonas keratitis at least in part by being a major chemoattractant for polymorphonuclear leukocytes (PMN) recruitment . Interestingly, the numbers of bacteria in eyes with neutralized MIP-2 activity did not decrease even though the severity of the disease was decreased . This implies PMNs as the major destructive factor in microbial keratitis . Further, neutralization of IL-1beta activity alone using monoclonal antibodies resulted in significant reduction of both MIP-2 and KC activity indicating that chemokine levels were regulated by IL-1beta . These studies demonstrate that the regulation of MIP-2 activity may be beneficial in reducing corneal damage during microbial keratitis in rodents and perhaps that regulation of the human homologue of MIP-2, IL-8, may be useful for controlling keratitis in humans . Nat Med, 2003 Mar, 9(3), 322 - 30 Epub 2003 Feb 03. Host defense against Pseudomonas aeruginosa requires ceramide-rich membrane rafts; Grassme H et al.; Pseudomonas aeruginosa infection is a serious complication in patients with cystic fibrosis and in immunocompromised individuals . Here we show that P . aeruginosa infection triggers activation of the acid sphingomyelinase and the release of ceramide in sphingolipid-rich rafts . Ceramide reorganizes these rafts into larger signaling platforms that are required to internalize P . aeruginosa, induce apoptosis and regulate the cytokine response in infected cells . Failure to generate ceramide-enriched membrane platforms in infected cells results in an unabated inflammatory response, massive release of interleukin (IL)-1 and septic death of mice . Our findings show that ceramide-enriched membrane platforms are central to the host defense against this potentially lethal pathogen. J Bacteriol, 2003 Feb, 185(4), 1316 - 25 Whole-genome sequence variation among multiple isolates of Pseudomonas aeruginosa; Spencer DH et al.; Whole-genome shotgun sequencing was used to study the sequence variation of three Pseudomonas aeruginosa isolates, two from clonal infections of cystic fibrosis patients and one from an aquatic environment, relative to the genomic sequence of reference strain PAO1 . The majority of the PAO1 genome is represented in these strains; however, at least three prominent islands of PAO1-specific sequence are apparent . Conversely, approximately 10% of the sequencing reads derived from each isolate fail to align with the PAO1 backbone . While average sequence variation among all strains is roughly 0.5%, regions of pronounced differences were evident in whole-genome scans of nucleotide diversity . We analyzed two such divergent loci, the pyoverdine and O-antigen biosynthesis regions, by complete resequencing . A thorough analysis of isolates collected over time from one of the cystic fibrosis patients revealed independent mutations resulting in the loss of O-antigen synthesis alternating with a mucoid phenotype . Overall, we conclude that most of the PAO1 genome represents a core P . aeruginosa backbone sequence while the strains addressed in this study possess additional genetic material that accounts for at least 10% of their genomes . Approximately half of these additional sequences are novel. J Antimicrob Chemother, 2003 Feb, 51(2), 423 - 6 Ex vivo synergy of arachidonate-enriched serum with ceftazidime and amikacin on multidrug-resistant Pseudomonas aeruginosa; Giamarellos-Bourboulis EJ et al.; Three multidrug-resistant strains of Pseudomonas aeruginosa were incubated ex vivo with sera sampled after a 10 min intravenous infusion of 25 mg/kg of arachidonic acid (AA) in 10 rabbits in the presence of ceftazidime and amikacin . Lipid peroxidation was assessed during bacterial growth . A statistically significant decrease in bacterial cells was found by the interaction of antimicrobials and serum sampled in the middle of infusion and 15 and 30 min after infusion of AA and was accompanied by elevated levels of malonodialdehyde . This effect of AA is probably attributed to lipid peroxidation and raises the possibility of its application in experimental infections. J Antimicrob Chemother, 2003 Feb, 51(2), 353 - 9 Antimicrobial-induced release of endotoxin from Pseudomonas aeruginosa: comparison of in vitro and animal models; Tsuji M et al.; This study was designed to compare the amount of lipopolysaccharide (LPS) induced following exposure to doripenem, imipenem/cilastatin, meropenem and ceftazidime in an in vitro computerized-simulation system (simulating the drug concentration pattern in human plasma after administration of a drug), with that induced by exposure to a drug at a constant concentration . When Pseudomonas aeruginosa was exposed to the test drugs at constant concentrations of 0.1 x, 1 x and 10 x MIC, differential relative induction of LPS was observed as follows: ceftazidime > meropenem, doripenem > imipenem/cilastatin . In the computerized-simulation system, however, the amount of LPS induced by treatment with ceftazidime (1 g) was similar to that by doripenem (250 mg), imipenem/cilastatin (500 mg) and meropenem (500 mg) . In a rat model of P . aeruginosa bacteraemia, rates of eradication of bacteria from the blood were similar for carbapenems and ceftazidime except for 1 h post-administration of ceftazidime . Serum LPS levels induced by treatment with doripenem (30 mg/kg), imipenem/cilastatin (30 mg/kg), meropenem/cilastatin (30 mg/kg) and ceftazidime (50 mg/kg) were almost the same at 3 h after administration of each drug . Data obtained from computerized-simulation systems might be more applicable than those obtained from organisms exposed to constant drug concentrations for estimating the amount of LPS in the plasma of human patients infected with Gram-negative bacteria. J Antimicrob Chemother, 2003 Feb, 51(2), 347 - 52 Multicentre surveillance of Pseudomonas aeruginosa susceptibility patterns in nosocomial infections; Van Eldere J; OBJECTIVES: To determine susceptibility rates and patterns in Pseudomonas aeruginosa strains isolated from nosocomial infections . METHODS: Seven hundred and sixteen P . aeruginosa isolates from 40 different hospitals in Belgium and the Grand Duchy of Luxembourg were collected in 1999 . RESULTS: Resistance rates varied significantly between hospitals . Of the fluoroquinolones, ciprofloxacin showed least resistance (24%), levofloxacin showed 27.5% resistance and ofloxacin 37.5% . Of the aminoglycosides, amikacin was the most potent antibiotic (10.5% resistance), followed by isepamicin (12%), tobramycin (19.5%) and gentamicin (23.5%) . Of the beta-lactam antibiotics, meropenem was the most active (9.5% resistance); piperacillin and piperacillin/tazobactam had, respectively, 24% and 17.5% resistance, ceftazidime 28.5%, cefepime 29.5%, ticarcillin/clavulanic acid 37% and aztreonam 55.5% . MIC distribution curves show the presence of significant subpopulations, with MICs just below breakpoint for many antibiotics . CONCLUSION: Resistance of P . aeruginosa to penicillins, cephalosporins, fluoroquinolones and aminoglycosides varies between hospitals, but is increasing. J Antimicrob Chemother, 2003 Feb, 51(2), 257 - 66 On functional and structural heterogeneity of VIM-type metallo-beta-lactamases; Docquier JD et al.; The VIM metallo-beta-lactamases are emerging resistance determinants, encoded by mobile genetic elements, that have recently been detected in multidrug-resistant nosocomial isolates of Pseudomonas aeruginosa and other Gram-negative pathogens . In this work a T7-based expression system for overproduction of the VIM-2 enzyme by Escherichia coli was developed, which yielded approximately 80 mg of protein per litre of culture . The enzyme was mostly released into the medium, from which it was recovered at >99% purity by an initial ammonium sulphate precipitation followed by two chromatography steps, with almost 80% efficiency . Determination of kinetic parameters of VIM-2 under the same experimental conditions previously used for VIM-1 (the first VIM-type enzyme detected in clinical isolates, which is 93% identical to VIM-2) revealed significant differences in K(m) values and/or turnover rates with several substrates, including penicillins, cephalosporins and carbapenems . Compared with VIM-1, VIM-2 is more susceptible to inactivation by chelators, indicating that the zinc ions of the latter are probably more loosely bound . These data indicated that at least some of the amino acid differences between the two proteins have functional significance . Molecular modelling of the two enzymes identified some amino acid substitutions, including those at positions 223, 224 and 228 (in the BBL numbering), that could be relevant to the changes in catalytic behaviour. Biomaterials, 2003 Apr, 24(9), 1663 - 70 Multiple surface properties of worn RGP lenses and adhesion of Pseudomonas aeruginosa; Bruinsma GM et al.; The aim of this study is to determine rigid gas permeable (RGP) lens surface properties prior to and after wear that are influential on adhesion of Pseudomonas aeruginosa . After 10 and 50 days of wear and after end-stage use, lenses were collected for determination of physico-chemical surface properties and bacterial adhesion in a parallel plate flow chamber . Water contact angles on unused RGP lenses amounted 47+/-13 degrees and were affected by wear . In addition, %O at the lens surfaces, as determined by X-ray photoelectron spectroscopy increased after use for 10 and 50 days, but decreased after end-stage wear . The %N hardly increased after wear and, in line, SDS-PAGE did not indicate adsorbed proteins . The surface roughness of the lenses, as measured by atomic force microscopy amounted 9 nm after 10 and 50 days of use, but end-stage lenses were significantly rougher (48+/-23 nm) . Moreover, initial deposition of P . aeruginosa #3 increased with increasing roughness for end-stage lenses . Multiple regression analysis, however, revealed that both physical and chemical surface properties were predictive for initial bacterial deposition to lens surfaces . After 10 days of wear, bacterial deposition was governed by the water contact angle, surface roughness, %O, %N, and %Si, while after 50 days of wear the surface roughness, %N, and %Si were found predictive for bacterial deposition . Initial bacterial deposition to end-stage lenses was solely dependent on the surface roughness . Summarizing, physico-chemical surface properties of RGP lenses change slightly during the first 10-50 days of wear, but end-stage lenses all had increased surface roughness, concurrent with increased bacterial adhesion. Am J Respir Crit Care Med, 2003 Feb 1, 167(3), 384 - 9 End-organ dysfunction in cystic fibrosis: association with angiotensin I converting enzyme and cytokine gene polymorphisms; Arkwright PD et al.; The clinical course of patients with cystic fibrosis (CF) with functionally similar mutations in the CF transmembrane conductance regulator gene is variable and must therefore relate to secondary genetic and environmental factors . We examined the hypothesis that polymorphisms of certain inflammatory mediator and regulatory genes affect clinical outcome by influencing the degree of end-organ damage . By studying the possible association between clinical outcome and angiotensin I-converting enzyme (ACE) and cytokine genotypes by amplification refractory mutation system-polymerase chain reaction, using stored DNA from 261 white patients with CF, we found that ultrasound features of cirrhosis occurred more frequently in patients with the high-producer (DD) rather than the low-producer (II) ACE genotype (odds ratio {95% confidence interval}, 3.7 {1.2 to 12}) . Moreover, significant pulmonary dysfunction (age at which FEV1 < 50%) was associated with the high-producer ACE genotype (2.3 {1.2 to 4.5}) and transforming growth factor-beta1 genotype (2.6 {1.0 to 6.8}) as well as with age at first colonization with Pseudomonas aeruginosa (9.1 {1.1 to 72}) . We conclude that the high-producer ACE genotype predicts patients with CF who have an increased chance of developing portal hypertension; and high-producer ACE and TGF-beta1 genotypes are secondary genetic factors contributing to pulmonary dysfunction in these patients. Sheng Wu Yi Xue Gong Cheng Xue Za Zhi, 1999 Dec, 16(4), 406 - 10 {Study of bacterial adhesion to prosthetic valve materials in vitro}; Huang Y et al.; This article reports a study of the bacterial adhesion to prosthetic valve materials in vitro . The method for assessing the degree of bacterial adhesion to prosthetic valve materials was established primarily . The capacities of staphylococcus aureus(SA), staphylococcus epidermidis(SE), Escherichia Coli(EC) and Pseudomonas aeruginosa(PA) for adhesion to Dacron, Pyrolytic carbon and polytetrofluoroethylene (PTFE) were quantitatively determined by the plate counting and Gamma-ray counting of 125I radiolabeled bacteria in vitro . The results showed that the capacities of four types of bacteria for adhesion to Dacron, Pyrolytic carbon and PTFE coincided with the bacterial-growth curve . The capacities of four bacteria for adhering to Dacron were stronger . The adhesion of SE to Pyrolytic carbon was the strongest . The adhesion of PA Kept up a high level . The capacities of EC and PA for adhering to PTFE were the strongest . The results indicate that the capacities of different types of bacteria for adhesion to the same prosthetic valve material are different, and the capacities of one type of bacteria for adhesion to different materials are also different. Se Pu, 1999 Jan, 17(1), 46 - 8 {Purification of outer membrane proteins in Pseudomonas aeruginosa by high performance ion-exchange liquid chromatography}; Zuo L et al.; Pseudomonas aeruginosa PAO1 was used in this study . Isolation of outer membrane was accomplished by treating the cell envelope with EDTA and lysozyme, followed by centrifugation . The outer membrane (10 mg of protein) was mixed with 34 mmol/L octyl beta-glucoside-5 mmol/L EDTA-10 mmol/L Tris-HCl (pH 8.0) and subjected to supersonic oscillation for 2 min . The centrifuged supernatant (100 kgf for 30 min at 20 degrees C) was applied onto a DEAE ion-exchange high performance liquid chromatographic column (TSK gel-DEAE-5PW column, 0.75 cm x 7.5 cm i.d.) that was equilibrated with a solution of 10 mmol/L Tris-HCl buffer (pH 8.0) containing 2.5 mmol/L beta-C12E8 and 1 mmol/L EDTA . The column was washed with the same solution and eluted with a linear gradient of 0-0.5 mol/L NaCl in the same solution and fractions A, B, C were collected . Proteins in these fractions were analyzed by SDS-polyacrylamide gel electrophoresis and quantified by the method of Lowry et al . Protein E(Mr 43,000), G(Mr 25,000) and H (Mr 19,000) flowed through the column without adsorption in fraction A . Protein C(Mr 70,000), D(Mr 46,000) and a small amount of F (Mr 34,000) were eluted in fraction B . Fraction A was concentrated with ultrafiltration and applied again onto a DEAE ion-exchange HPLC column equilibrated with 10 mmol/L Tris-HCl buffer, pH 8.0, containing 34 mmol/L beta-C12E8 and 1 mmol/L MgCl2 . Fraction B was subjected to DEAE ion-exchange HPLC column in the presence of EDTA . This fraction was then applied onto a DEAE ion-exchange HPLC column equilibrated with 10 mmol/L Tris-HCl buffer, pH 8.0, containing 34 mmol/L octylglucoside and 1 mmol/L EDTA . By these procedures protein C, D and E were purified to apparent homogeneity as judged by SDS-PAGE . In this work, we purified the outer membrane proteins of Pseudomonas aeruginosa, and used a new technique selectively solubilizing the cytoplasmic membrane with sodium lauryl sarcosinate for isolating the outer membrane proteins of Pseudomonas aeruginosa because of its relative simplicity. DNA Repair (Amst), 2003 Mar 1, 2(3), 273 - 84 recX, a new SOS gene that is co-transcribed with the recA gene in Escherichia coli; Pages V et al.; recX is a small open reading frame located downstream of recA that is conserved in many bacteria . In Escherichia coli, the recX gene (also named oraA) is a 501 bp open reading frame that encodes a predicted basic protein . Transcriptional analysis by Northern blots showed that in E . coli the recX gene is SOS-regulated . Primer extension data and transcriptional fusions indicate that recX transcription is down regulated with respect to recA by an intrinsic transcription terminator that is located between the recA and recX coding sequences . Despite the presence of this terminator, a recA-recX message resulting from transcriptional readthrough is detected at a level of 5-10% of the recA message . In addition, transcriptional/translational fusion experiments show that recX expression is further down regulated at the translational level reaching an estimated protein level about 500-fold lower than RecA . Strains in which the recX gene was disrupted were constructed by insertion of an antibiotic resistance cassette . The survival after UV irradiation, the spontaneous and UV-induced mutation rates were not significantly different in these recX strains compared to the corresponding wild type strain . Overexpression of RecA was shown to be lethal in a recX deletion strain in Pseudomonas aeruginosa {J . Bacteriol . 175 (1993) 2451}, Mycobacterium tuberculosis {Mol . Microbiol . 30 (1998) 525} and Streptomyces lividans {J . Bacteriol . 182 (2000) 4005} suggesting that the recX gene may act as a regulator of recA . In contrast in E . coli, in a recX deletion strain, RecA overexpression is neither toxic nor is the expression of the recA(+) gene affected in a recX deletion strain at the basal level or after UV induction. J Antibiot (Tokyo), 2002 Nov, 55(11), 975 - 92 S-3578, a new broad spectrum parenteral cephalosporin exhibiting potent activity against both methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa . Synthesis and structure-activity relationships; Yoshizawa H et al.; A series of 7-aminothiadiazolylcephalosporins having a 1-(substituted)-1H-imidazo{4,5-b}pyridinium group at the C-3' position of the cephem nucleus were synthesized and evaluated for in vitro antibacterial activities . Among the cephalosporins prepared in this study, 7beta-{2-(5-amino-1,2,4-thiadiazol-3-yl)-2(Z)-ethoxyiminoacetamido}-3-{1-(3-methylaminopropyl)-1H-imidazo{4,5-b}pyridinium-4-yl}methyl-3-cephem-4-carboxylate sulfate (S-3578) showed extremely potent broad spectrum activity against both gram-positive bacteria including methicillin-resistant Staphylococcus aureus (MRSA) and gram-negative bacteria including Pseudomonas aeruginosa, and good water solubility. Hua Xi Yi Ke Da Xue Xue Bao, 2000 Sep, 31(3), 334 - 7 {A clinical study on PA-MSHA vaccine used for adjuvant therapy of lymphoma and lung cancer}; Li Z et al.; The objective of this study was to evaluate the effectiveness and safety of pseudomonas aeruginosa MSHA vaccine (PA-MSHA vaccine) used as an immune modulator . The study was carried out after the design of a non-blind, randomized controlled trial . The malignant lymphoma patients were divided into experiment group (45 cases) and control group (43 cases) . Likewise were distributed the lung cancer patients: 44 cases in experiment group and 45 cases in control group . The two experiment groups received chemotherapy + PA-MSHA vaccine . The two control groups were given chemotherapy alone . The results showed that the clinical efficacy rate was 95.56% for the exp . group and 69.77% (P < 0.01) for the control group of the malignant lymphoma cases; the clinical efficacy rate was 59.09% for the exp . group and 42.22% (P < 0.01) for the control group of the lung cancer cases . The infection rate was 17.78% for the exp . group and 37.21% (P < 0.05) for the control group of the malignant lymphoma cases; the infection rate was 15.91% for the exp . group and 40.00% (P < 0.05) for the control group of the lung cancer cases . The comprehensive immune effectiveness rates for the exp . group and control group of the malignant lymphoma cases were 77.78% and 23.26% (P < 0.01) respectively . The comprehensive immune effectiveness rates for the exp . group and control group of the lung cancer cases were 84.09% and 35.56% (P < 0.01) respectively . Adverse reactions were found in 5 cases, of which, one was given medical care while the others automatically recovered . These results indicate that PA-MSHA vaccine, as a new kind of immune modulator, can improve the effectiveness of treatment for tumor with low adverse reaction rate. Trans Am Ophthalmol Soc, 2002, 100, 243 - 71 The use of antimicrobial peptides in ophthalmology: an experimental study in corneal preservation and the management of bacterial keratitis; Mannis MJ; PURPOSE: Bacterial keratitis is an ocular infection with the potential to cause significant visual impairment . Increasing patterns of antibiotic resistance have necessitated the development of new antimicrobial agents for use in bacterial keratitis and other serious ocular infections . With a view to exploring the use of novel antimicrobial peptides in the management of ocular infection, we performed a series of experiments using synthetic antimicrobial peptides designed for the eradication of common and serious ophthalmic pathogens . METHODS: Experiments were performed with three clinical ocular isolates--Pseudomonas aeruginosa, Staphylococcus aureus, and Staphylococcus epidermidis--in three experimental settings: (1) in vitro in a controlled system of 10 mM sodium phosphate buffer, (2) in vitro in modified chondroitin sulfate-based corneal preservation media (Optisol), and (3) in an in vivo animal model (rabbit) simulating bacterial keratitis . In all cases, outcomes were measured by quantitative microbiological techniques . RESULTS: The candidate peptides (CCI A, B, and C and COL-1) produced a total reduction of the test pathogens in phosphate buffered saline . In modified Optisol, the peptides were effective against S epidermidis at all temperatures, demonstrated augmented activity at 23 degrees C against the gram-positive organisms, but were ineffective against P aeruginosa . The addition of EDTA to the medium augmented the killing of P aeruginosa but made no difference in the reduction of gram-positive organisms . In an in vivo rabbit model of Pseudomonas keratitis, COL-1 demonstrated neither clinical nor microbicidal efficacy and appeared to have a very narrow dosage range, outside of which it appeared to be toxic to the ocular surface . CONCLUSION: Our data indicate that the antimicrobial peptides we tested were effective in vitro but not in vivo . In an age of increasing antibiotic resistance, antimicrobial peptides, developed over millions of years as innate defense mechanisms by plants and animals, may have significant potential for development as topical agents for the management of severe bacterial keratitis . However, modifications of the peptides, the drug delivery systems, or both, will be necessary for effective clinical application. Antimicrob Agents Chemother, 2003 Feb, 47(2), 582 - 7 Biochemical characterization of the acquired metallo-beta-lactamase SPM-1 from Pseudomonas aeruginosa; Murphy TA et al.; SPM-1 is a new metallo-beta-lactamase recently identified in Pseudomonas aeruginosa strain 48-1997A, isolated in Sao Paulo, Brazil . Kinetic analysis demonstrated that SPM-1 has a broad hydrolytic profile across a wide range of beta-lactam antibiotics . Considerable variation was observed within the penicillin, cephalosporin, and carbapenem subfamilies; however, on the whole, SPM-1 appears to preferentially hydrolyze cephalosporins . The highest k(cat/)K(m) ratios (in micromolar per second) overall were observed for this subgroup . The hydrolytic profile of SPM-1 bears the most similarity to that of the metallo-beta-lactamase IMP-1, yet for the most part, SPM-1 has k(cat)/K(m) values higher than those of IMP-1 . Zinc chelator studies established that progressive inhibition of SPM-1 by EDTA, dipicolinic acid, and 1-10-o-phenanthroline demonstrated a biexponential pattern in which none of the chelators completely inhibited SPM-1 . A homology model of SPM-1 was developed on the basis of the IMP-1 crystal structure, which showed the protein folding and active-site structure characteristic of metallo-beta-lactamases and which provides an explanation for the kinetic profiles observed. Burns, 2003 Feb, 29(1), 43 - 8 Effects of dietary arginine supplementation on antibody production and antioxidant enzyme activity in burned mice; Shang HF et al.; This study investigated the effect of arginine (Arg) supplementation on specific antibody production and antioxidant enzyme activities in burned mice vaccinated with detoxified Pseudomonas exotoxin A linked with the outer membrane proteins I and F, named PEIF . Also, the survival rate of burned mice complicated with Pseudomonas aeruginosa was evaluated . Experiment 1: Thirty BALB/c mice were assigned to two groups . One group was fed a control diet with casein as the protein source, while the other group was supplemented with 2% Arg in addition to casein . The two groups were isonitrogenous . The mice were immunized twice with PEIF, and the production of specific antibodies against PEIF was measured every week . After 8 weeks, all mice received a 30% body surface area burn injury . Mice were sacrificed 24h after the burn . The antioxidant enzyme activities and lipid peroxides in the tissues as well as the specific antibody production were analyzed . Experiment 2: Twenty-eight mice were divided into two groups and vaccinated as described in experiment 1 . After the burn the mice were infected with P . aeruginosa, and the survival rate was observed for 8 days . The results demonstrated that antioxidant enzyme activities and lipid peroxides in tissues were significantly lower in the Arg group than in the control group after the burn . The production of specific antibodies against P . aeruginosa significantly increased in the Arg group at 4 and 7 weeks after immunization, and 24h after the burn . The survival rates of vaccinated burned mice after bacterial infection did not significantly differ between the two groups . These results suggest that vaccinating mice with Arg supplementation may enhance humoral immunity and attenuate the oxidative stress induced by burn injury . However, Arg supplementation did not improve survival in vaccinated mice complicated with P . aeruginosa infection. Intensive Care Med, 2003 Mar, 29(3), 396 - 402 Epub 2003 Jan 23. Bactericidal activity response of blood neutrophils from critically ill patients to in vitro granulocyte colony-stimulating factor stimulation; Yang K et al.; OBJECTIVE: Neutrophil function impairment is common in nonneutropenic critically ill patients . Whether granulocyte colony-stimulating factor (G-CSF) may be useful for preventing nosocomial infection in these patients is debated . The response of blood neutrophils from critically ill patients to G-CSF was investigated in vitro . DESIGN AND SETTING: Prospective study, laboratory investigation in two intensive care units . PATIENTS: 52 critically ill patients without immunosuppression . MEASUREMENTS: Neutrophils obtained from 52 patients on the 5th day of their intensive care unit stay were incubated with and without G-CSF (1, 10, 100 ng/ml) . Reactive oxygen species (ROS) release and bactericidal activity against Staphylococcus aureus and Pseudomonas aeruginosa were evaluated . Plasma cytokines (interleukin 10, tumor necrosis factor alpha, and G-CSF) were measured . RESULTS: Median values (25th-75th percentiles) indicated no stimulatory effect of G-CSF on neutrophil bactericidal activity against either organism: S . aureus, 100% (95-109) of the unstimulated condition with 1 ng/ml G-CSF, and P . aeruginosa, 102% (98-109) with 1 ng/ml G-CSF . However, wide interindividual variability was found, ranging from marked inhibition to marked stimulation . Similar variability was found for ROS release . No correlations were found between ROS release and bactericidal activities against either bacterial strain . Inhibition of neutrophil bactericidal activity by G-CSF was associated with significantly higher plasma interleukin 10 concentrations . Plasma G-CSF levels were significantly higher in patients whose neutrophil bactericidal activity was unresponsive to G-CSF, suggesting G-CSF receptor downregulation . CONCLUSIONS: The effect of G-CSF on in vitro neutrophil bactericidal activity varied widely, depending on endogenous levels of G-CSF and was not predictable based on severity scores. Am J Respir Cell Mol Biol, 2003 Feb, 28(2), 249 - 56 Surfactant protein A and D differently regulate the immune response to nonmucoid Pseudomonas aeruginosa and its lipopolysaccharide; Bufler P et al.; We investigated the role of the surfactant proteins (SPs) A and D in the pulmonary immune defense of nonmucoid strains of Pseudomonas aeruginosa, the most etiologic agents of nosocomial Pseudomonas pneumonia . We first examined the interactions of recombinant human SP-D dodecamers and purified natural or recombinant human SP-A with two smooth, and two rough, clinical isolates of nonmucoid P . aeruginosa . SP-D bound to all four isolates, but agglutinated only one rough and one smooth strain . SP-D functioned as an opsonin to enhance the uptake of all four strains by the human monocytic cell line Mono Mac 6 (MM6) . SP-D also enhanced tumor necrosis factor-alpha secretion by MM6 cells in response to purified lipopolysaccharide (LPS) isolated from the rough, but not the smooth, strains . Although SP-A bound to all four strains, it did not cause bacterial aggregation or enhance uptake . It showed small but statistically significant inhibitory effects on the cytokine response of MM6 cells to one strain of smooth organisms, but did not significantly alter the response to purified LPS . This study in combination with previously published data strongly suggests that SP-D may play important roles in the local innate pulmonary defense against nonmucoid P . aeruginosa of diverse LPS phenotypes, and preferentially augments the cellular response to rough P . aeruginosa endotoxin. Clin Infect Dis, 2003 Feb 1, 36(3), e55 - 7 Epub 2003 Jan 20. Hot tub-associated necrotizing pneumonia due to Pseudomonas aeruginosa; Crnich CJ et al.; We describe a case of severe necrotizing pneumonia due to community-acquired Pseudomonas aeruginosa . Cultures of fluid obtained from the filter of the patient's hot tub grew the same P . aeruginosa strain as that grown from culture of the patient's sputum . Centers for Disease Control and Prevention guidelines should be strictly followed for hot tub maintenance to prevent P . aeruginosa overgrowth: the range of free chlorine levels in the water should be kept at 1-3 mg/L, and the pH should be kept at 7.2-7.8. Pediatr Res, 2003 Feb, 53(2), 313 - 9 IL-10 controls Aspergillus fumigatus- and Pseudomonas aeruginosa-specific T-cell response in cystic fibrosis; Casaulta C et al.; Up to 90% of patients with cystic fibrosis (CF) are chronically colonized with Pseudomonas aeruginosa, and 10% to 50% of CF patients are colonized with Aspergillus fumigatus . Despite an extensive inflammatory reaction, patients cannot eliminate the microorganisms . The present study demonstrates that an IL-10 mediated T-cell tolerance to major infectious agents A . fumigatus and P . aeruginosa plays an important role in the control of T-cell-mediated inflammatory responses in CF . Peripheral blood mononuclear cells of CF patients secreted significantly higher amounts of IL-10 . T-cell response against recombinant A . fumigatus antigens rAsp f 3, rAsp f 4, rAsp f 6, and heat-inactivated P . aeruginosa was controlled by IL-10 . Proliferation and interferon-gamma production was significantly increased when endogenous IL-10 was blocked in aspergillus and pseudomonas antigen-stimulated cells of CF patients . The role of IL-10 was further documented by increased spontaneous proliferation of peripheral blood mononuclear cells of CF patients after preincubation with antisense oligonucleotides blocking the synthesis of IL-10 receptor-associated kinases janus tyrosine kinase 1 and tyrosine kinase 2 . Together, these data demonstrate an important role of IL-10-mediated peripheral T-cell tolerance to P . aeruginosa and A . fumigatus in the control of the intensity of the inflammatory T-cell response in CF. Environ Microbiol, 2002 Dec, 4(12), 883 - 97 Pseudomonas aeruginosa O-antigen chain length is determined before ligation to lipid A core; Daniels C et al.; Pseudomonas aeruginosa is a Gram-negative opportunistic pathogen that infects immunocompromised patients and trauma victims and causes fatal lung infections in people with cystic fibrosis . This microorganism produces a number of virulence factors, one of which is lipopolysaccharide (LPS), which has been shown to mediate many biological effects including resistance to serum killing and phagocytosis . These biological activities have been correlated to the length of the O-polysaccharide and its distribution on the outer membrane . Wzz is responsible for regulation of the size distribution of the O-antigen . Wzz has been found to participate solely in the Wzy-dependent pathway for LPS biosynthesis, which produces heteropolymeric O-polysaccharide such as the B-band LPS of P . aeruginosa . Our laboratory has previously reported characterization of a Wzz protein encoded in the B-band O-antigen biosynthesis cluster of PAO1 . The availability of the genome sequence of P . aeruginosa PAO1 has made it possible to identify a second functional Wzz protein (PA0938, Wzz2) . Gene replacement was used to generate an unmarked wzz2delta knock-out and a wzz2delta/wzz1::Gm double knock-out . As expected, the wzz2delta strain produced LPS with modal length imparted by Wzz1, and the wzz2delta/wzz1::Gm strain produced LPS O-antigen with a non-modal (random) length . Both wzz1 and wzz2 from P . aeruginosa PAO1 were cloned and expressed with an N-terminal His6 tag . His6-Wzz1 and His6-Wzz2 were purified to near homogeneity by immobilized metal affinity chromatography (IMAC) . These preparations were used to develop specific polyclonal antibodies against each of the proteins . In vivo protein cross-linking followed by Western immunoblotting indicated that Wzz1 forms dimers whereas Wzz2 forms octamers . By generation of a wzz2delta/rmlC double mutant and analysis of the LPS, we have made the novel observation that polymerization of modal chain length-distributed O-antigen occurred before ligation to the lipid A core . We have shown an association between the Wzz proteins and O-antigen polymer chains using immunoprecipitation with anti-O5 O-antigen monoclonal antibody MF15-4 . Both Wzz1 and Wzz2 could be co-precipitated with O5 polymer. Environ Microbiol, 2002 Dec, 4(12), 872 - 82 Analysis of the Pseudomonas aeruginosa oprD gene from clinical and environmental isolates; Pirnay JP et al.; Genomes are constantly evolving . Our report highlights the wide mutational diversity of clinical as well as environmental isolates, compared with the laboratory strain(s), through the systematic genetic analysis of a chromosomal porin gene (oprD) in relation to a specific antibiotic resistance . Mutational inactivation of the oprD gene is associated with carbapenem resistance in Pseudomonas aeruginosa . The sequence of the oprD gene of 55 Pseudomonas aeruginosa natural isolates obtained from across the world--from sources as diverse as patients and rhizospheres--was analysed . A microscale mosaic structure for this gene--resulting from multiple intra- and possibly interspecies recombinational events--is reported . An array of independent and seemingly fast-occurring defective oprD mutations were found, none of which had been described before . A burn wound isolate demonstrated unusually high overall sequence variability typical of mutator strains . We also present evidence for the existence of OprD homologues in other fluorescent pseudomonads. J Bacteriol, 2003 Feb, 185(3), 1071 - 81 Microarray analysis of global gene expression in mucoid Pseudomonas aeruginosa; Firoved AM et al.; Pseudomonas aeruginosa is the dominant pathogen causing chronic respiratory infections in cystic fibrosis (CF) . After an initial phase characterized by intermittent infections, a chronic colonization is established in CF upon the conversion of P . aeruginosa to the mucoid, exopolysaccharide alginate-overproducing phenotype . The emergence of mucoid P . aeruginosa in CF is associated with respiratory decline and poor prognosis . The switch to mucoidy in most CF isolates is caused by mutations in the mucA gene encoding an anti-sigma factor . The mutations in mucA result in the activation of the alternative sigma factor AlgU, the P . aeruginosa ortholog of Escherichia coli extreme stress sigma factor sigma(E) . Because of the global nature of the regulators of mucoidy, we have hypothesized that other genes, in addition to those specific for alginate production, must be induced upon conversion to mucoidy, and their production may contribute to the pathogenesis in CF . Here we applied microarray analysis to identify on the whole-genome scale those genes that are coinduced with the AlgU sigmulon upon conversion to mucoidy . Gene expression profiles of AlgU-dependent conversion to mucoidy revealed coinduction of a specific subset of known virulence determinants (the major protease elastase gene, alkaline metalloproteinase gene aprA, and the protease secretion factor genes aprE and aprF) or toxic factors (cyanide synthase) that may have implications for disease in CF . Analysis of promoter regions of the most highly induced genes (>40-fold, P < or = 10(-4)) revealed a previously unrecognized, putative AlgU promoter upstream of the osmotically inducible gene osmE . This newly identified AlgU-dependent promoter of osmE was confirmed by mapping the mRNA 5' end by primer extension . The recognition of genes induced in mucoid P . aeruginosa, other than those associated with alginate biosynthesis, reported here revealed the identity of previously unappreciated factors potentially contributing to the morbidity and mortality caused by mucoid P . aeruginosa in CF. Biol Reprod, 2003 Feb, 68(2), 509 - 15 Messenger RNA (mRNA) expression for the antimicrobial peptides beta-defensin-1 and beta-defensin-2 in the male rat reproductive tract: beta-defensin-1 mRNA in initial segment and caput epididymidis is regulated by androgens and not bacterial lipopolysaccharides; Palladino MA et al.; Mechanisms of antimicrobial protection in male reproductive organs are poorly understood . Defensins are antimicrobial peptides produced by many epithelial tissues . The goals of the present study were 1) . to test the hypothesis that adult rat male reproductive organs express mRNA for rat beta-defensin (RBD)-1 and RBD-2, 2) . to examine if defensin mRNA expression in the testis and epididymis is induced by bacterial lipopolysaccharides (LPS), and 3) . to investigate the effects of androgens on defensin mRNA expression in the epididymis . Total RNA from reproductive organs was analyzed by relative reverse transcription-polymerase chain reaction analysis . RBD-1 mRNA was detected in the testis . All segments of epididymis expressed equal levels of RBD-1 mRNA with higher expression than in the testis, whereas accessory sex glands showed expression equal to that in the testis . Expression of RBD-2 mRNA was primarily restricted to the penis . Effects of inflammation on defensin mRNA expression were examined in rats administered a unilateral injection of LPS from Pseudomonas aeruginosa or Escherichia coli . Expression of RBD-1 mRNA in the testis and epididymis was unaffected by LPS . To test the hypothesis that circulating androgens regulate RBD-1 mRNA expression in the epididymis, rats were subjected to bilateral orchiectomy (orch) or to orch plus a 3.5-cm implant containing testosterone . Expression of RBD-1 mRNA in the initial segment and caput was unchanged following 1-day orch but showed androgen-sensitive expression after 5 and 15 days . Expression of RBD-1 mRNA in corpus and cauda was not affected by orch . Results of this study suggest that RBD-1 may play an antimicrobial role in the testis and epididymis. J Microbiol Methods, 2003 Mar, 52(3), 379 - 88 A comparative study of carboxyfluorescein diacetate and carboxyfluorescein diacetate succinimidyl ester as indicators of bacterial activity; Hoefel D et al.; Staining bacteria with esterified fluorogenic substrates followed by flow cytometric analysis offers a means for rapid detection of metabolically active bacteria . Flow cytometry (FCM) was used to assess carboxyfluorescein diacetate (CFDA) and carboxyfluorescein diacetate succinimidyl ester (CFDA/SE) as indicators of bacterial activity for cultured bacteria, including Aeromonas hydrophila, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus epidermidis and bacteria from environmental waters . In theory, CFDA/SE should be a better indicator of metabolic bacterial activity compared to CFDA due to greater intracellular retention of the fluorescent product . Qualitative and quantitative analysis of exponential phase cultures, mixtures of active and inactive cells and bacteria from environmental waters revealed CFDA was successful in detecting active bacteria, whereas CFDA/SE was not . CFDA/SE labelled inactive cells with intensities equal to that of the active population and could not even discriminate between bacteria in exponential phase growth and a fixed cell preparation . We propose that the specific mode of action of the succinimidyl ester (SE) group in combination with the nonenzymatic aqueous hydrolysis of the CFDA moiety results in the nonspecific labelling of all cells, irrespective of their metabolic state . This study shows that CFDA/SE is a poor marker of bacterial activity. J Microbiol Methods, 2003 Mar, 52(3), 361 - 6 Development of a high throughput Pseudomonas aeruginosa epithelial cell adhesion assay; Swanson B et al.; Pseudomonas aeruginosa colonizes the lungs of cystic fibrosis and mechanically ventilated patients by binding to specific carbohydrate residues on the surface of lung epithelial cells . Studies have shown that blocking this interaction may have therapeutic effects in vivo . To test compounds that may have an effect on the binding of P . aeruginosa to epithelial cells, we have developed a pseudomonal adhesion assay that is compatible with high throughput technology . This assay utilizes a 96-well culture plate assay and P . aeruginosa strains that have been modified to bioluminesce . This method has proven to be a rapid, sensitive and reproducible system for screening agents that inhibit bacterial adhesion. J Enzyme Inhib Med Chem, 2002 Aug, 17(4), 261 - 6 Unsymmetrical 1,1'-disubstituted ferrocenes: synthesis of Co(ii), Cu(ii), Ni(ii) and Zn(ii) chelates of ferrocenyl -1-thiadiazolo-1'-tetrazole, -1-thiadiazolo-1'-triazole and -1-tetrazolo-1'-triazole with antimicrobial properties; Chohan ZH et al.; Condensation reactions of 1,1''-diacetylferrocene with different heteroaromatic amines such as, 2-amino-1,3,4-thiadiazole, 5-aminotetrazole and 3-amino-1,2,4-triazole to form unsymmetrically 1,1'-disubstituted ferrocenes have been studied . The obtained compounds have been further investigated for their liganding and biological properties upon chelation with Co(II), Cu(II), Ni(II) and Zn(II) metal ions . The synthesized compounds have been characterized by physical, spectral and analytical data and have been screened against pathogenic bacterial strains e.g., Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus, showing moderate activity as antibacterials in vitro. J Enzyme Inhib Med Chem, 2002 Aug, 17(4), 235 - 46 Characterization of competitive inhibitors for the transferase activity of Pseudomonas aeruginosa exotoxin A; Armstrong S et al.; A series of small, nonpolar compounds were tested for their ability to inhibit the ADP-ribosyl transferase activity of Pseudomonas aeruginosa exotoxin A . The IC50 values for the compounds tested ranged from 87 nM to 484 microM for NAP and CMP12, respectively . It was demonstrated that NAP was a competitive inhibitor of the ADPRT reaction for the NAD+ substrate with a Ki of 45 +/- 5 nM, which was in good agreement with the dissociation constant determined independently (KD = 56 +/- 6 nM) . The IC50 value for NAP was 87 +/- 12 nM, which strongly correlated with the Ki and KD values . Furthermore, NAP was shown to noncovalently associate with the exotoxin A active site using exhaustive dialysis, NMR, and electrospray mass spectrometry . Finally, a computer molecular model using the X-ray structure of the substrate-bound toxin was generated with NAP bound to the active site of exotoxin A at the nicotinamide-binding site . This model is consistent with the X-ray structure of the catalytic domain of poly-ADP-ribose polymerase co