Clin Genet, 2002 Oct, 62(4), 325 - 7 Analysis of the two common alpha-1-antitrypsin deficiency alleles PiMS and PiMZ as modifiers of Pseudomonas aeruginosa susceptibility in cystic fibrosis; Meyer P et al.; Lung disease is the direct cause of death in more than 90% of cystic fibrosis (CF) patients . Proteinase-antiproteinase imbalances are common in CF and alpha-1-antitrypsin (AAT) deficiency . We investigated the hypothesis that the AAT deficiency alleles PiS and PiZ contribute to pulmonary prognosis in CF . Two hundred and sixty-nine CF patients from Southern Germany were included in this study . The serum concentrations of AAT and C-reactive protein (CRP) were determined by nephelometry, and patients were screened by polymerase chain reaction (PCR) and restriction enzyme digest for the common AAT deficiency alleles PiS and PiZ . The onset of chronic bacterial colonization by Pseudomonas aeruginosa (Pae) was correlated with the AAT phenotypes PiMM, PiMS and PiMZ . Only three out of nine CF patients (33%) diagnosed with either PiMS or PiMZ had developed chronic Pae lung infection earlier in their lives . The remaining six patients showing a PiMS or PiMZ phenotype showed a later onset of chronic Pae lung infection . Our results indicate that PiMS and PiMZ are not associated with worse pulmonary prognosis in CF . These data need to be confirmed in studies with a much larger number of cases. J Immunol, 2002 Oct 15, 169(8), 4522 - 30 Pseudomonas aeruginosa activates human mast cells to induce neutrophil transendothelial migration via mast cell-derived IL-1 alpha and beta; Lin TJ et al.; The mechanisms of neutrophil (PMN) recruitment to Pseudomonas aeruginosa infection remain incompletely defined . Mast cells (MC) involvement in this process has not been studied previously . In this study, we demonstrate that human cord blood-derived MC phagocytose P . aeruginosa and release mediators that activate HUVEC monolayers for supporting PMN transmigration . Pretreatment of supernatants from P . aeruginosa-MC cocultures with neutralizing anti-IL-1alpha plus anti-IL-1beta Abs, or IL-1R antagonist before addition to HUVEC for stimulation completely abrogated MC-induced PMN transmigration, while anti-TNF-alpha treatment had no effect . The expression of E-selectin and ICAM-1 on HUVEC, the latter a ligand for PMN CD11/CD18, was significantly up-regulated by P . aeruginosa-induced MC mediators . Pretreatment of human PMN with anti-CD18 mAb or pretreatment of HUVEC with a combination of three mAbs (against ICAM-1, ICAM-2, and E-selectin) inhibited by 85% the MC-dependent PMN transmigration . Moreover, P . aeruginosa-induced production of IL-1alpha and IL-1beta was down-regulated by IL-10 and dexamethasone . This study demonstrates for the first time that MC may mediate P . aeruginosa-induced PMN recruitment via production of IL-1alpha and beta . These findings have important implications for diseases involving P . aeruginosa infection and suggest novel targets for modulating P . aeruginosa-induced inflammation. Microbiology, 2002 Oct, 148(Pt 10), 3195 - 202 Physiological responses of Pseudomonas aeruginosa PAO1 to oxidative stress in controlled microaerobic and aerobic cultures; Sabra W et al.; Pseudomonas aeruginosa PAO1 was found to exhibit several remarkable physiological responses to oxidative stress upon its growth in a computer-controlled suspension culture . First, it strongly reduced the transfer rate of oxygen from the gas into the liquid phase, causing oxygen-limited or microaerophilic conditions in the culture after a short period of cultivation, even at high aeration rates with pure oxygen . Second, PAO1 that was previously classified as 'non-mucoid' formed a clear polysaccharide capsule on the cell surface (mucoid phenotype) under oxidative-stress conditions . Third, the strain showed a reduced growth rate and a longer lag phase under high oxygen tension . Finally, P . aeruginosa PAO1 released a high amount of proteins into the culture broth . The release of some virulence factors by PAO1, such as elastase, was significantly enhanced or only occurred under microaerobic conditions (i.e . dissolved oxygen tension value around 1% of air saturation) . Hence, it is concluded that P . aeruginosa PAO1 prefers microaerobic conditions for growth and for the formation of some of its virulence factors . PAO1 can create such growth conditions by at least two mechanisms: (i) blockage of the transfer of oxygen and (ii) formation of a polysaccharide capsule on the cell surface . It is postulated that the blockage of oxygen transfer may play an important role in the defence of this pathogen against reactive oxygen intermediates. Microbiology, 2002 Oct, 148(Pt 10), 3183 - 93 The Pseudomonas aeruginosa alternative sigma factor PvdS controls exotoxin A expression and is expressed in lung infections associated with cystic fibrosis; Hunt TA et al.; PvdS is an alternative sigma factor regulated by the global iron regulator Fur . It has been demonstrated that PvdS plays a role in the iron-dependent regulation of exotoxin A (ETA) in Pseudomonas aeruginosa strain PAO1 . The goals of this research were to determine if pvdS was transcribed by the bacteria in the chronic lung infections associated with cystic fibrosis (CF) and to determine how PvdS interacts with the regAB promoters of the hyper-toxigenic strain PA103 . It was found that pvdS is transcribed in the lungs of patients with CF and that it appears to be involved with the regulation of toxA in this environment . This correlated with the finding that in strain PA103, a mutation in pvdS reduced ETA activity while the same mutation in strain PAO1 abrogated ETA production . It was also shown that in strain PA103, pvdS was absolutely required for activation of the regAB P2 promoter . The effect of PvdS on the P2 promoter may be direct or indirect; however, in support of a direct role, an eight-out-of-nine base-pair match to the consensus sequence for PvdS binding was identified at the transcriptional start site for the P2 promoter . The effect of PvdS on the PA103 regAB P1 promoter under aerobic growth conditions was also examined . The results show that PvdS does modulate the expression from this promoter but that both the regAB operon and PvdS are required for optimal P1 promoter activity . These studies demonstrate that the alternative sigma factor PvdS acts as a regulator of ETA expression in P . aeruginosa strain PA103 through the regAB operon and that PvdS is expressed in lung infections associated with CF. Microbiology, 2002 Oct, 148(Pt 10), 2987 - 96 A polymorphic region in Mycobacterium abscessus contains a novel insertion sequence element; Howard ST et al.; A polymorphic region was discovered in the genetically uncharacterized opportunistic pathogen Mycobacterium abscessus . The region contains a novel 1.7 kb insertion sequence (IS) named ISMab1 . ISMab1 contains two complete ORFs and one partial ORF located in segments with over 80% nucleotide identity to Mycobacterium avium IS1601 and IS999 and to previously unreported IS-like elements from Mycobacterium smegmatis . The marked similarity within this family of elements is supportive of horizontal transfer between environmental mycobacterial species . In clinical isolates, ISMab1 was either present as a single copy or absent . The polymorphic region containing ISMab1 was identified by genomic subtraction between a parental strain and phenotypic variant . The variant has a 14.2 kb genomic deletion and this is flanked in the parental strain by complex arrays of inverted and direct repeats . Clinical isolates of M . abscessus were probed for the deletion and flanking sequences and two were found to be missing more than 20 kb . No regional deletions were found in the type strain, ATCC 19977 . Although M . abscessus is a rapidly growing species, comparative sequence analysis of 23 kb from the polymorphic region showed that most local ORFs have greater amino acid identity to proteins encoded by genes from the slowly growing mycobacteria, M . avium and Mycobacterium tuberculosis, than to the rapid-grower M . smegmatis . Several ORFs also have strong similarity to Pseudomonas aeruginosa genes with a potential role in beta-oxidation. Clin Exp Optom, 2002 Sep, 85(5), 271 - 8 The pathogenesis of bacterial keratitis: studies with Pseudomonas aeruginosa; Fleiszig SM et al.; Bacterial keratitis is a sight-threatening corneal disease that is most commonly associated with the extended wear of soft contact lenses . Over the past decade, we have investigated the pathogenesis of infectious keratitis involving the opportunistic pathogen Pseudomonas aeruginosa . Our research has focused on understanding the respective roles of bacteria and host in the establishment of this infection . Here, we provide a current perspective on P . aeruginosa keratitis, reviewing some of the research developments that have helped shape our views on the mechanisms by which pathogen and host response cause corneal disease . P . aeruginosa may provide a model for the pathogenesis of bacterial keratitis and help further elucidate the complex array of host factors that normally protect the cornea from infectious agents. J Enzyme Inhib Med Chem, 2002 Feb, 17(1), 1 - 7 Antibacterial Schiff bases of oxalyl-hydrazine/diamide incorporating pyrrolyl and salicylyl moieties and of their zinc(II) complexes; Chohan ZH et al.; Schiff bases derived from oxaldiamide/oxalylhydrazine and pyrrol-2-carbaldehyde, or salicylaldehyde respectively, as well as their Zn(II) complexes have been prepared and tested as antibacterial agents . These Schiff bases function as tetradentate ligands, forming octahedral Zn(II) complexes . The ketonic form for the diamide derived Schiff base and the enolic form of the hydrazide derived Schiff base were the preferred tautomers for coordination of the metal ions . The title compounds and their Zn(II) derivatives were evaluated for antibacterial activity against several bacterial strains which easily develop resistance to classical antibiotics, such as Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa . Some of them showed promising biological activity in inhibiting the growth of such organisms. Proteomics, 2002 Sep, 2(9), 1325 - 46 Proteomic comparison of membrane and extracellular proteins from invasive (PAO1) and cytotoxic (6206) strains of Pseudomonas aeruginosa; Nouwens AS et al.; Strains of Pseudomonas aeruginosa can be phenotypically classified by their mode of pathogenicity as either invasive, where the bacterium is internalised by host cells, or cytotoxic, where the host cell is killed without internalisation through the expression of cytotoxicity factors . These phenotypes are thought to depend primarily on the interactions of pseudomonal membrane and secreted proteins with host cells . We report here comparisons of outer membrane and extracellular protein-enriched fractions from invasive (PAO1) and cytotoxic (6206) strains of P . aeruginosa separated by two-dimensional (2-D) gel electrophoresis . Gel image comparisons revealed the two strains express essentially identical membrane protein profiles under the conditions investigated . Membrane protein strain differences were typically the result of minor amino acid sequence variations resulting in small mass and isoelectric point shifts visible on 2-D gels . Analysis of extracellular proteins from stationary phase growth, however, revealed significantly different protein profiles . Extracellular fractions from the invasive PAO1 strain were dominated by extracellular proteases including elastase (LasB), LasA protease and chitin-binding protein, as well as several previously designated 'hypothetical' proteins . LasB appeared to be highly processed with 28 discrete mass and isoelectric point forms detected in this study . The significant number of active extracellular proteases (including LasB itself) may account for this processing . Conversely, extracellular fractions from strain 6206 consisted mainly of cellular and membrane exposed proteins including GroEL, DnaK and flagellar subunits . These are thought to result from cellular turnover during growth and the reliance on the secretory mechanisms of this strain to produce high levels of cytotoxicity factors, such as ExoU, which may be produced only upon specific interactions with host cells . These studies will aid in elucidating the differences between invasive and cytotoxic P . aeruginosa at the proteome level. J Cutan Med Surg, 2003 Jan-Feb, 7(1), 1 - 6 Epub 2002 Oct 09. Barrier and antibacterial properties of 2-octyl cyanoacrylate-derived wound treatment films; Mertz PM et al.; BACKGROUND: Besides enhancing healing, an ideal dressing should prevent invasion of pathogens and control the number of bacteria already present in the wounds . OBJECTIVE: To evaluate the barrier and antimicrobial properties of a cyanoacrylate-based bandage (LAB) against Staphylococcus aureus or Pseudomonas aeruginosa on partial thickness wounds in swine . METHODS: Barrier study: Bacteria were inoculated over test materials (LAB, standard bandage, air-exposed) that were placed over wounds . The bacteria from wounds were quantitated at 24, 48, and 72 hours postinoculation . Antimicrobial study: Wounds inoculated with bacteria were covered with LAB, standard bandage, or hydrocolloid bandage or left air-exposed . The bacteria recovered from wounds were quantitated at 24 and 72 hours after treatment . RESULTS: Barrier study: No bacteria were recovered from LAB-treated wounds . Antimicrobial study: LAB reduced the number of inoculated bacteria in comparison to all other groups . CONCLUSION: LAB is effective in protecting wounds from external bacterial invasion and reducing bacterial contamination. Am J Respir Crit Care Med, 2002 Oct 1, 166(7), 988 - 93 Epidemiology of Pseudomonas aeruginosa in cystic fibrosis in British Columbia, Canada; Speert DP et al.; Pseudomonas aeruginosa is the most common respiratory pathogen in patients with cystic fibrosis (CF), but the predominant mechanism by which it is acquired is controversial . To determine the frequency of patient-to-patient spread, we evaluated P . aeruginosa isolates from 174 patients treated at the CF clinics in Vancouver, BC, Canada, since 1981 . Multiple isolates were obtained from each patient and genetically typed by random amplified polymorphic DNA and pulsed field gel electrophoresis analyses . A total of 157 genetic types of P . aeruginosa was identified, 123 of which were unique to individual patients . A total of 34 types was shared by more than one patient; epidemiologic evidence linked these individuals only in the cases of 10 sibships and 1 pair of unrelated patients . We conclude that there is an extremely low risk in Vancouver for patients with CF to acquire P . aeruginosa from other patients . It appears that prolonged close contact, such as occurs between siblings, is necessary for patient-to-patient spread . The major source of acquisition of P . aeruginosa in CF appears to be from the environment . Considering these observations, we do not recommend segregation of patients with CF on the basis of their colonization status with P . aeruginosa. Am J Respir Crit Care Med, 2002 Oct 1, 166(7), 983 - 7 Detection of a widespread clone of Pseudomonas aeruginosa in a pediatric cystic fibrosis clinic; Armstrong DS et al.; Cross-infection by Pseudomonas aeruginosa between unrelated patients with cystic fibrosis (CF) is believed to be uncommon . After detecting a genotypically identical strain of P . aeruginosa in five unrelated children with CF dying from severe lung disease, we determined its prevalence within a large CF clinic using pulsed-field gel electrophoresis and random amplified polymorphic DNA assays . The clinical status of P . aeruginosa-infected patients was also determined . Between September and December 1999, 152 patients, aged 3.9-20.7 years, provided sputum for culture . P . aeruginosa was detected in 118 children of mean (SD) age 13.5 (3.8) years . The genotyping techniques were concordant, showing that 65 (55%) infected patients carried an indistinguishable or closely related strain . No distinctive antibiogram or environmental reservoir was found . Patients with the clonal strain were more likely than those with unrelated isolates to have been hospitalized in the preceding 12 months for respiratory exacerbations . This study demonstrates extensive spread of a single, clonal strain of P . aeruginosa in a large pediatric CF clinic . Whether this strain is also more virulent than sporadic isolates remains to be determined . As transmissible strains could emerge elsewhere, other CF clinics may also need to consider molecular methods of surveillance for cross-infection. Vet Dermatol, 2002 Oct, 13(5), 247 - 51 Isolation and characterization of Pseudomonas aeruginosa from sheep with fleece rot in northern and middle Jordan; El-Sukhon SN; A total of 162 sheep fleece samples were collected from 2315 sheep clinically examined for evidence of dermatitis . The sheep belonged to 32 flocks raised in northern and middle Jordan . Eighty-three samples showed no obvious abnormalities, whereas the remainder showed exudation (79 samples), fleece discoloration (18) and fleece roughness (40) and abscesses (7) . Seventeen Pseudomonas aeruginosa isolates were obtained from these samples . Antibacterial resistance in vitro was common; resistance to tetracycline, amoxycillin, erythromycin and cotrimoxazole was shown by > 90% of the isolates . Resistance to norfloxacin (29.4% of isolates), ciprofloxacin (17.6%) and amikacin (17.6%) was also demonstrated . Fourteen isolates were serum resistant when assessed after 1-3 h incubation in sheep and calf sera, and their count increased by 2-2.9 and 2.5-3.5 respectively. Eur Respir J, 2002 Sep, 20(3), 658 - 64 A randomised clinical trial of nebulised tobramycin or colistin in cystic fibrosis; Hodson ME et al.; Chronic infection with Pseudomonas aeruginosa is associated with progressive deterioration in lung function in cystic fibrosis (CF) patients . The purpose of this trial was to assess the efficacy and safety of tobramycin nebuliser solution (TNS) and nebulised colistin in CF patients chronically infected with P . aeruginosa . One-hundred and fifteen patients, aged > or = 6 yrs, were randomised to receive either TNS or colistin, twice daily for 4 weeks . The primary end point was an evaluation of the relative change in lung function from baseline, as measured by forced expiratory volume in one second % predicted . Secondary end points included changes in sputum P . aeruginosa density, tobramycin/colistin minimum inhibitory concentrations and safety assessments . TNS produced a mean 6.7% improvement in lung function (p=0.006), whilst there was no significant improvement in the colistin-treated patients (mean change 0.37%) . Both nebulised antibiotic regimens produced a significant decrease in the sputum P . aeruginosa density, and there was no development of highly resistant strains over the course of the study . The safety profile for both nebulised antibiotics was good . Tobramycin nebuliser solution significantly improved lung function of patients with cystic fibrosis chronically infected with Pseudomonas aeruginosa, but colistin did not, in this study of 1-month's duration . Both treatments reduced the bacterial load. Pediatr Pulmonol, 2002 Nov, 34(5), 336 - 41 Do in-line respiratory filters protect patients? Comparing bacterial removal efficiency of six filters; Canakis AM et al.; With all pulmonary function diagnostic and respiratory therapy equipment, cross-infection has always been a concern, especially in the cystic fibrosis population, in whom pulmonary function tests are done routinely . The aim of this study was to identify and compare the bacterial removal efficiency (BRE, ability of a filter to remove microorganisms) of six different filters used in hospital settings: Microgard (MG), Spirobac (SB), PALL (PL), and KOKO (KK), used in the pulmonary function laboratory; and Clear-Guard (CG) and Respigard (RG), used in ventilator circuits . Filters were tested in both saturated and nonsaturated conditions . A Pseudomonas aeruginosa suspension of 1 x 10(4) to 1 x 10(8) CFU/mL was nebulized onto each filter . A blood agar plate was held immediately downstream from the filter . Colony-forming units (CFU) were then counted after 24 hr of incubation . A peak flow was applied across the spirometry filters . Bacterial thresholds of the filters were also identified (concentration of bacteria at which a filter no longer has 100% BRE) . There was a significant difference in BRE among the six filters in saturated states when challenged with 1 x 10(4) CFU/mL (MG, KK, CG, and RG, 100%; SB, 98.8%; PL, 42.7%; P = 0.003) . There was no significant difference between saturated and nonsaturated states, or after application of a peak flow . Filter thresholds were significantly different (KK 1 x 10(8), MG 1 x 10(7), CG 1 x 10(6), RG 1 x 10(5), and SB and PL <1 x 10(4) CFU/mL) . In conclusion, when all filters are exposed to the same extreme challenges, significant differences exist in their ability to remove bacteria . J Antimicrob Chemother, 2002 Oct, 50(4), 479 - 86 Evaluation of media available for testing the susceptibility of Pseudomonas aeruginosa by BSAC methodology; Andrews J et al.; BSAC methodology was used to study media available from four manufacturers for susceptibility testing of Pseudomonas aeruginosa in the UK and Ireland . Fifty isolates of P . aeruginosa, including ATCC and NCTC control strains, were studied by disc testing methods by 20 centres around the UK and Ireland and by MIC determination at the BSAC Standardized Method Development Centre (SMDC) in Birmingham, UK . Although many of the antibiotics tested gave similar zone diameters for a particular strain-antibiotic combination irrespective of the medium used for testing, significant differences in media performance were noted for the aminoglycosides, imipenem and colistin . The data generated showed that for testing aminoglycosides, zone diameters on two of the agars were significantly larger than those on Oxoid IsoSensitest agar-the recommended medium for the BSAC method . For imipenem, zones were smaller on one of the agars and for colistin, zones were larger on one of the agars in comparison with those on Oxoid agar . Scattergram analysis of zone diameters and MICs of colistin indicated that the zone diameter breakpoints should be adjusted . Media purported to be equivalent to Oxoid IsoSensitest agar do not give the same zone sizes with some agents and should not be used until standards for media performance have been established and the media have been shown to perform adequately. Tuberculosis (Edinb), 2002, 82(2-3), 85 - 90 Is Mycobacterium tuberculosis a closer relative to Gram-positive or Gram-negative bacterial pathogens? Fu LM, Fu-Liu CS. The phylogenetic position of Mycobacterium tuberculosis relative to other bacteria is controversial . Its cell wall has characteristics of both Gram-positive and Gram-negative bacteria . In the standard reference of bacterial phylogeny based on 16S ribosomal RNA sequence comparison, M . tuberculosis belongs to the high G+C Gram-positive bacteria that form a monophyletic group with the low G+C Gram-positive bacteria such as Bacillus subtilis . Some analyses indicate no particular relationship between these two groups . The availability of the complete genome sequence of M . tuberculosis allows us to reexamine this issue from genomic perspectives, as genome-based phylogenies may be more representative of the evolutionary history of whole organisms than molecular trees . In the genome tree constructed based on conserved gene content, M . tuberculosis is more related to Gram-negative than to Gram-positive bacteria as reflected by the evolutionary distance between nearest ancestral units . This conclusion may be supported by another analysis showing that M . tuberculosis shares relatively more orthologous genes for energy production and conversion with Gram-negative bacteria, in particular, Escherichia coli and Pseudomonas aeruginosa, than with Gram-positive bacteria. Eur J Biochem, 2002 Oct, 269(19), 4738 - 45 The outer membrane component of the multidrug efflux pump from Pseudomonas aeruginosa may be a gated channel; Yoshihara E et al.; OprM, the outer membrane component of the MexAB-OprM multidrug efflux pump of Pseudomonas aeruginosa, has been assumed to facilitate the export of antibiotics across the outer membrane of this organism . Here we purified to homogeneity the OprM protein, reconstituted it into liposome membranes, and tested its channel activity by using the liposome swelling assay . It was demonstrated that OprM is a channel-forming protein and exhibits the channel property that amino acids diffuse more efficiently than saccharides . However, antibiotics showed no significant diffusion through the OprM channel in the liposome membrane, suggesting that OprM functions as a gated channel . We reasoned that the protease treatment may cause the disturbance of the gate structure of OprM . Hence, we treated OprM reconstituted in the membranes with alpha-chymotrypsin and examined its solute permeability . The results demonstrated that the protease treatment caused the opening of an OprM channel through which antibiotics were able to diffuse . To elucidate which cleavage is intimately related to the opening, we constructed mutant OprM proteins where the amino acid at the cleavage site was replaced with another amino acid . By examining the channel activity of these mutant proteins, it was shown that the proteolysis at tyrosine 185 and tyrosine 196 of OprM caused the channel opening . Furthermore, these residues were shown to face into the periplasmic space and interact with other component(s) . We considered the possible opening mechanism of the OprM channel based on the structure of TolC, a homologue of OprM. Shock, 2002 Sep, 18(3), 236 - 41 Heparin nebulization attenuates acute lung injury in sepsis following smoke inhalation in sheep; Murakami K et al.; Pseudomonas pneumonia is a common complication of smoke inhalation injury . Airway casts formed from clotted mucous occur frequently in this condition . A recent report shows that intravenous heparin improves oxygenation and reduces lung damage in a sheep model of smoke inhalation . We hypothesized that nebulized heparin could be an effective means of reducing cast formation . Female sheep (n = 19) were surgically prepared for a study of acute lung injury (ALI) . After a tracheotomy, 48 breaths of cotton smoke (<40 degrees C) were inflated into the airway . Afterwards, live Pseudomonas aeruginosa (5 x 10(11) CFU) was instilled into the lung . All sheep were mechanically ventilated with 100% O2 and were divided into four groups: a heparin-nebulized group (n = 5; animals received aerosolized heparin {10,000 I.U.} 1 h after the bacterial instillation and subsequently every 4 h thereafter), an intravenous heparin group (n = 5,300 U/kg/23 h, infusion was started 1 h after the injury), a saline-nebulization group (n = 5; animals received inhaled nebulized saline), and a sham injury group (n = 4, treated in the same fashion, but no injury) . The animals were sacrificed after 24 h of mechanical ventilation, and lung samples were harvested . Sheep exposed to lung injury presented with typical hyperdynamic cardiovascular changes and a corresponding drop in PaO2 . These changes were significantly attenuated in the heparin groups . Histological changes consisting of cellular infiltrates, lung edema, congestion, and cast formation were reduced by heparin . These data suggest that nebulized inhaled heparin is a beneficial therapy for sepsis-induced ALI. Acta Crystallogr D Biol Crystallogr, 2002 Oct, 58(Pt 10 Pt 2), 1874 - 5 Epub 2002 Sep 28. Crystallization and preliminary X-ray crystallographic analysis of peptide deformylase from Pseudomonas aeruginosa; Kim HW et al.; Peptide deformylase (PDF) from the pathogenic bacterium Pseudomonas aeruginosa has been overexpressed in Escherichia coli and crystallized in the presence of its inhibitor actinonin at 297 K using polyethylene glycol (PEG) 4000 as a precipitant . The diffraction limit and the spot shape of the crystals could be slightly improved by the crystal annealing/dehydration procedure . X-ray diffraction data to 1.85 A have been collected using synchrotron radiation . The crystal belongs to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 68.75, b = 74.46, c = 77.18 A . The asymmetric unit contains two subunits of peptide deformylase, with a corresponding crystal volume per protein mass (V(M)) of 2.45 A(3) Da(-1) and a solvent content of 49.8%. FEMS Microbiol Lett, 2002 Sep 10, 214(2), 217 - 22 Metabolic engineering of Escherichia coli for the production of medium-chain-length polyhydroxyalkanoates rich in specific monomers; Park SJ et al.; The Escherichia coli fabG(Ec) gene and the Pseudomonas aeruginosa rhlG(Pa) gene, which encode 3-ketoacyl-acyl carrier protein reductase, were expressed in E . coli W3110 and its fadA mutant strain WA101 to examine their roles in medium-chain-length (MCL) polyhydroxyalkanoate (PHA) biosynthesis from fatty acids . When one of these 3-ketoacyl-acyl carrier protein reductase genes was co-expressed with the Pseudomonas sp . 61-3 PHA synthase gene (phaC2(Ps)) in E . coli W3110, MCL-PHA composed mainly of 3-hydroxyoctanoate and 3-hydroxydecanoate was synthesized from sodium decanoate . When the fabG(Ec) gene and the phaC2(Ps) gene were co-expressed in the fadA mutant E . coli strain WA101, MCL-PHA rich in 3-hydroxydecanoate monomer up to 93 mol% was accumulated from sodium decanoate . This was possible by efficiently redirecting 3-ketoacyl-coenzymes A from the beta-oxidation pathway to the PHA biosynthesis pathway without losing two carbon units, the strategy of which can be extended for the production of MCL-PHAs rich in other specific monomers. Appl Environ Microbiol, 2002 Oct, 68(10), 5096 - 103 Variability in Pseudomonas aeruginosa lipopolysaccharide expression during crude oil degradation; Norman RS et al.; Bacterial utilization of crude oil components, such as the n-alkanes, requires complex cell surface adaptation to allow adherence to oil . To better understand microbial cell surface adaptation to growth on crude oil, the cell surface characteristics of two Pseudomonas aeruginosa strains, U1 and U3, both isolated from the same crude oil-degrading microbial community enriched on Bonny Light crude oil (BLC), were compared . Analysis of growth rates demonstrated an increased lag time for U1 cells compared to U3 cells . Amendment with EDTA inhibited U1 and U3 growth and degradation of the n-alkane component of BLC, suggesting a link between cell surface structure and crude oil degradation . U1 cells demonstrated a smooth-to-rough colony morphology transition when grown on BLC, while U3 cells exhibited rough colony morphology at the outset . Combining high-resolution atomic force microscopy of the cell surface and sodium dodecyl sulfate-polyacrylamide gel electrophoresis of extracted lipopolysaccharides (LPS), we demonstrate that isolates grown on BLC have reduced O-antigen expression compared with that of glucose-grown cells . The loss of O-antigen resulted in shorter LPS molecules, increased cell surface hydrophobicity, and increased n-alkane degradation. Biomaterials, 2002 Dec, 23(23), 4565 - 72 Polyclonal human antibodies reduce bacterial attachment to soft contact lens and corneal cell surfaces; Rediske AM et al.; Bacterial keratitis due to Pseudomonas aeruginosa is a potentially serious complication of extended-wear contact lens use . Adhesion of P . aeruginosa to soft contact lens materials or corneal endothelial cells in the presence of pooled human immunoglobulins and/or neutrophils in artificial tear fluid was studied in vitro as a potential method to treat contact lens-associated infection . Soft hydrophilic contact lens materials equilibrated in sterile saline were soaked in artificial tear fluid for 18 h prior to use . P . aeruginosa IFO 3455 was added to groups of lenses or confluent cultured bovine corneal endothelial cells with varying amounts of human polyclonal immunoglobulin (IgG) and human blood neutrophils or serum albumin as a control . After 2 or 4 h incubation, adherent viable bacteria on lenses were quantified . Fluorescence microscopy was used to assess bacterial adherence to bovine corneal endothelial cells in the presence and absence of IgG and neutrophils . Various concentrations of albumin had no effect on adhesion . Human immunoglobulin solutions (25 mg/ml) reduced P . aeruginosa adhesion by nearly 1 log and 2 logs after 2 and 4 h incubations, respectively . Neutrophils in combination with 25 mg/ml IgG reduced bacterial adhesion approximately 1 log over reduction in adhesion by neutrophils alone . Diluted human IgG (10 mg/ml) did not significantly decrease bacterial adhesion after 2 or 4 h, but did reduce adhesion in combination with human neutrophils at both time points . Similar reductions in amounts of fluorescently labeled bacteria adhered to cultured monolayers of corneal endothelial cells under these conditions were qualitatively observed. Hepatology, 2002 Oct, 36(4 Pt 1), 918 - 26 Analysis of TCR antagonism and molecular mimicry of an HLA-A0201-restricted CTL epitope in primary biliary cirrhosis; Kita H et al.; Although the etiology and mechanism of primary biliary cirrhosis (PBC) is unknown, growing evidence suggests a major role for T cells . We have recently identified the first CD8 T-cell epitope, amino acid 159-167 of the E2 component of pyruvate dehydrogenase complexes (PDC-E2) . To seek for analogue peptide-antagonizing effector function of CTLs specific for this autoantigen, we examined the effector functions of the PDC-E2-specific CTLs against alanine substituted peptides . Furthermore, because molecular mimicry has been postulated as a possible cause of initiating PBC, we carried out studies aimed at identifying naturally occurring peptides for the 159-167 peptide of PDC-E2 that may serve as agonists . An alanine substitution at position 5 of this epitope significantly reduced peptide-specific effector functions of CTLs . Moreover, this analogue peptide inhibited effector functions of the CTLs to the prototype peptide, including cytotoxicity and IFN-gamma production . We also identified a peptide derived from Pseudomonas aeruginosa, which showed a higher binding affinity to the HLA-A*0201 than the prototype peptide . This homologous peptide was recognized by CTLs specific for the prototype epitope on PDC-E2 . In conclusion, a modification of the immunodominant autoepitope can be utilized to manipulate the CD8 T-cell responses against the autoantigen PDC-E2 . Our finding also supports the thesis that molecular mimicry may be implicated in the initiation of the autoreactive CD8 T-cell responses and has implications for the use of such peptides for immunotherapy. Cell Physiol Biochem, 2002, 12(4), 207 - 14 Pseudomonas aeruginosa triggered apoptosis of human epithelial cells depends on the temperature during infection; Fillon S et al.; The induction of apoptosis is a hallmark in many bacterial infections . Here, we show that the environmental temperature during infection influences P . aeruginosainduced apoptosis in human conjunctiva epithelial Chang cells . Infection with the clinical isolate P . aeruginosa762 at 37 degrees C resulted in a rapid induction of apoptosis within 30 min . Apoptosis was mediated by upregulation of CD95-receptor expression on the surface of the infected cells and depolarisation of the mitochondrial membrane potential (DeltaPhim) as determined by FACS-analysis of immunostained cells or of cells loaded with the potential sensitive dye JC1 respectively . In contrast, P . aeruginosafailed to induce significant apoptosis and mitochondrial alterations at 22 degrees C . The loss of the apoptotic response at 22 degrees C correlated with the failure of the epithelial cells to upregulate CD95, while bacterial growth or secretion of bacterial exotoxins into the culture supernatant appeared to be not affected . From our data we conclude that P . aeruginosa762 induced apoptosis is dependent on the temperature during infection and that cellular pathways leading to CD95-upregulation are inhibited at low temperature . J Biol Chem, 2002 Nov 29, 277(48), 46669 - 75 Epub 2002 Sep 20. Insight into the catalytic mechanism of Pseudomonas aeruginosa exotoxin A . Studies of toxin interaction with eukaryotic elongation factor-2; Armstrong S et al.; The molecular nature of the protein-protein interactions between the catalytic domain from Pseudomonas aeruginosa exotoxin A (PE24H) and its protein substrate, eukaryotic elongation factor-2 (eEF-2) were probed using a fluorescence resonance energy transfer method . Single cysteine mutant proteins of PE24H were prepared and site-specifically labeled with the donor fluorophore IAEDANS (5-(2-iodoacetylaminoethylamino)-1-napthalenesulfonic acid), whereas eEF-2 was labeled with the acceptor fluorophore fluorescein . The association was found to be independent of ionic strength and of the co-substrate, NAD(+) but dependent upon pH . The lack of requirement for NAD(+) to produce the toxin-eEF-2 complex demonstrates that the catalytic process is a random order mechanism, thereby disputing the current model . The previously observed pH dependence for catalytic function can be assigned to the toxin-eEF-2 binding event, as the pH dependence of binding observed in this study showed a strong correlation with enzymatic activity . The ability of the toxin to bind eEF-2 with bound GTP/GDP was assessed using nonhydrolyzable analogues . The results from the substrate binding and catalytic activity experiments indicate that PE24H is able to interact and bind with eEF-2 in all of its guanyl nucleotide-induced conformational states . Thus, the toxin ribosylates eEF-2 regardless of the nucleotide-charged state of eEF-2 . These results represent the first detailed characterization of the molecular details and physiological conditions governing this protein-protein interaction. J Bacteriol, 2002 Oct, 184(20), 5633 - 40 Divergent structure and regulatory mechanism of proline catabolic systems: characterization of the putAP proline catabolic operon of Pseudomonas aeruginosa PAO1 and its regulation by PruR, an AraC/XylS family protein; Nakada Y et al.; Pseudomonas aeruginosa PAO1 utilizes proline as the sole source of carbon and nitrogen via a bifunctional enzyme (the putA gene product) that has both proline dehydrogenase (EC 1.5.99.8) and pyrroline 5-carboxylate dehydrogenase (EC 1.5.1.12) activities . We characterized the pruR-putAP loci encoding the proline catabolic system of this strain . In contrast to the putA and putP (encoding proline permease) genes of other gram- negative bacteria, which are located at divergent or separate loci, Northern blotting demonstrated that the two genes form an operon in strain PAO1 . While the phylogenetic lineage of the PutP protein of strain PAO1 was related to that of the origin (80% identity to the P . putida counterpart), PutA of PAO1 (PutA(PAO)) was rather distantly related (47% identity) to the P . putida counterpart . Moreover, unlike the PutA proteins of P . putida and enteric bacteria, PutA(PAO) appeared to lack a regulatory function . Upstream of the putAP operon, the divergent PA0781 gene specified a hypothetical outer membrane protein with a molecular weight of 74,202 . This gene appeared to be dispensable for proline utilization as indicated by the normal growth of a knockout mutant of PA0781 on medium containing proline . The pruR (proline utilization regulator) gene immediately upstream of PA0781 encoded a transcriptional activator of the AraC/XylS protein family and mediated the proline-responsive expression of putAP . Primer extension studies identified a PruR-dependent promoter responsive to proline in the 5'-flanking region of putA . Thus, the proline utilization system of P . aeruginosa differs from that of P . putida with respect to putA structure, the organization of the putAP genes, and the regulatory mechanism of putA expression. Clin Sci (Lond), 2002 Oct, 103(4), 417 - 24 Cystic fibrosis transmembrane conductance regulator (CFTR) activity in nasal epithelial cells from cystic fibrosis patients with severe genotypes; Andersson C et al.; Cystic fibrosis is a heterogenic disease, in which the phenotype can also vary for patients with the same genotype . In the present study the function of the cystic fibrosis transmembrane conductance regulator (CFTR) in nasal epithelial cells from 19 adult patients with cystic fibrosis was investigated . All patients had severe mutations, whereby no or little functional CFTR is expected in the plasma membrane . Of the patients, 15 were homozygous for deltaF508-CFTR (i.e . CTFR lacking residue Phe-508) . The others were deltaF508-heterozygous with 3659delC, 394delTT or 2183AA-->G . Nasal epithelial cells, obtained by nasal brushings, were loaded with the fluorescent probe N -(ethoxycarbonylmethyl)-6-methoxyquinolinium bromide to measure Cl(-) efflux . In most of the cystic fibrosis patients, forskolin plus isobutylmethylxanthine was unable to elicit any response . Unexpectedly, cells from three cystic fibrosis patients (two deltaF508/deltaF508 patients and one deltaF508/3659delC patient) responded to stimulation in a wild-type manner . It was investigated whether this residual chloride transport function was associated with a milder phenotype . Clinical parameters studied were lung function, number of antibiotic courses, Shwachman score, Bhalla score, age at chronic colonization with Pseudomonas aeruginosa and the pattern of essential fatty acids in serum phospholipids . Unknown factors may affect the presence of functional CFTR in patients with severe CFTR mutations . However, we could not find a correlation between the response to cAMP and any of the phenotype parameters . It appears that functional cAMP transport in the nasal epithelium is no guarantee of a mild phenotype and, conversely, that a patient lacking cAMP-dependent chloride transport can develop a mild phenotype. Indian J Med Res, 2002 Apr, 115, 153 - 7 Prevalence of extended spectrum beta lactamase producing gram negative bacteria in a tertiary care hospital; Mathur P et al.; BACKGROUND & OBJECTIVES: Extended spectrum beta lactamase (ESBL) producing Gram negative bacteria are increasingly being associated with hospital infections thereby rendering all beta lactams, except carbapenems ineffective in the treatment of infections related to these organisms . A knowledge about their prevalence is essential to guide the appropriate antibiotic treatment of severe infections in hospitalized patients . The present work was carried out to study the prevalence of ESBL producing Gram negative bacteria in a tertiary care hospital . METHODS: A total of 678 Gram negative bacteria were included in the study . They were isolated from various clinical samples obtained from indoor patients admitted to the All India Institute of Medical Sciences, New Delhi during March to June 2001 . These isolates were screened for ESBL production by the inhibitor based test recommended by the National Committee for Clinical Laboratory Standards (NCCLS) using Klebsiella pneumoniae ATCC 700603 as positive control and Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853 as negative controls . RESULTS: Out of the 678 strains tested, 458 (68%) were found to be ESBL producers . Among the bacterial species, ESBL production was most common in Klebsiella spp . (80%) . The proportion of ESBL positive isolates was highest from intensive care units (79%), followed by Medical Oncology (75%), Medical (54%) and Surgical wards (50%) . INTERPRETATION & CONCLUSION: A high prevalence of ESBL positive isolates was found in our hospital . This has important implications as carbapenems remain the only choice of treatment for infections caused by these organisms . The control measures include judicious use of antibiotics and implementation of appropriate infection control measures to control the spread of these strains in the hospital. J Virol, 2002 Oct, 76(20), 10437 - 43 Bronchoalveolar fluid is not a major hindrance to virus-mediated gene therapy in cystic fibrosis; Rooney CP et al.; Successfully targeting the airway epithelium is essential for gene therapy of some pulmonary diseases . However, the airway epithelium is resistant to virus-mediated gene transfer with commonly used vectors . Vectors that interact with endogenously expressed receptors on the apical surface significantly increase gene transfer efficiency . However, other endogenous components involved in host immunity may hinder virus-mediated gene transfer . We tested the effect of bronchoalveolar lavage liquid (BAL) from patients with cystic fibrosis (CF), BAL from subjects without CF (non-CF BAL), Pseudomonas aeruginosa-derived proteins, and an array of inflammatory proteins on gene transfer mediated by adeno-associated virus type 5 (AAV5) and adenovirus targeted to an apically expressed glycosylphosphatidylinositol-modified coxsackie-adenovirus receptor . We found that neither CF BAL nor its components had a significant effect on gene transfer to human airway epithelium by these vectors . Non-CF BAL significantly impaired adenovirus-mediated gene transfer . Removal of immunoglobulins in non-CF BAL restored gene transfer efficiency . As virus vectors are improved and mechanisms of humoral immunity are elucidated, barriers to successful gene therapy found in the complex environment of the human lung can be circumvented. Vet Ophthalmol, 2002 Sep, 5(3), 217 - 20 Squamous cell carcinoma associated with a periorbital mass in a veiled chameleon (Chamaeleo calyptratus); Abou-Madi N et al.; This report describes a squamous cell carcinoma in a 1-year-old female veiled chameleon (Chamaeleo calyptratus) . The lesion developed as a small (1 by 1 mm) left periocular discoloration of a scale never involving the eye . The mass was first diagnosed as an abscess, increased in size (4 by 8 by 3 mm), and recurred after two surgical resections combined with antibiotic therapy . Poor nutritional condition and egg production by the chameleon complicated management of this condition . The mass was removed surgically a third time at which point histopathologic evaluation revealed a locally invasive squamous cell carcinoma . Bacterial culture of the mass isolated a pure culture of Pseudomonas aeruginosa . Ceftazidime was administered at 20 mg/kg IM every 48 h for 20 days . The animal died 3 months later from complications during an ovariohysterectomy for pregnancy toxemia and oviduct inertia . Necropsy showed no local recurrence or metastasis of the tumor. Antimicrob Agents Chemother, 2002 Oct, 46(10), 3286 - 7 Carbapenem-resistant Pseudomonas aeruginosa in malaysia producing IMP-7 beta-lactamase; Ho SE et al.; We have isolated and identified a carbapenem-resistant Pseudomonas aeruginosa strain from Malaysia that produces an IMP-7 metallo-beta-lactamase . This isolate showed high-level resistance to meropenem and imipenem, the MICs of which were 256 and 128 micro g/ml, respectively . Isoelectric focusing analyses revealed pI values of >9.0, 8.2, and 7.8, which indicated the possible presence of IMP and OXA . DNA sequencing confirmed the identity of the IMP-7 determinant. Res Microbiol, 2002 Jul-Aug, 153(6), 339 - 44 Alkane biodegradation in Pseudomonas aeruginosa strains isolated from a polluted zone: identification of alkB and alkB-related genes; Belhaj A et al.; Pseudomonas aeruginosa strains that grow on crude oil as the sole source of carbon and energy were isolated from an environment in Morocco polluted by petroleum refinery effluents . The twenty isolates grew on saturated alkanes from C12 to C22 . Three of the isolates were also able to grow on low molecular weight C6 to C10 n-alkanes, but the other 17 strains were not . The strains were tested for alkB and a/kB-related genes encoding alkane-1-monooxygenase (alkane hydroxylase) . Oligonucleotide primers specific for the alkB gene of strain P . putida (GPo1 ) and for the alkB1 and alkB2 genes of P . aeruginosa strain PAO1 allowed amplification from the P . aeruginosa isolates of fragments similar to alkB1 and alkB2 genes of strain PAO1 . Only 3 strains carried an alkB gene very similar to that of strain GPo1, and these strains were the same ones that could utilise C6 to C10 n-alkanes. Curr Microbiol, 2002 Nov, 45(5), 350 - 4 Transcription levels of Pseudomonas aeruginosa exotoxin a gene and severity of symptoms in patients with otitis externa; Matar GM et al.; Polymerase chain reaction (PCR)-based detection and transcription of the gene encoding a potent virulence factor, the exotoxin A, were done on 32 isolates of Pseudomonas aeruginosa belonging to 23 genotypes . These isolates were obtained from 22 patients who were admitted to the emergency room in a medical center during a 5-month period with the diagnosis of either unilateral or bilateral otitis externa . Patients showed symptoms that ranged from mild to severe . PCR amplification of a 396-bp fragment of the gene encoding the exotoxin A was done on extracted DNA . Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) was performed on extracted RNA to detect exotoxin A gene mRNA transcripts . Quantitation of RT-PCR amplicons from P . aeruginosa isolates associated with mild and severe symptoms was determined by end-point titration of c-DNA and scanning of amplicons with the Storm Gel and Blot Imaging System . Data have shown that all of the 32 isolates of P . aeruginosa carry the exotoxin A gene, and all isolates with the exception of two had the exotoxin A transcription demonstrated by the production of a 396-bp amplicon from RT-PCR-amplified RNA . The remaining two isolates amplified fragments that were slightly smaller than the expected size . Additional studies are needed to characterize these two mRNA transcripts . Transcription levels of exotoxin A gene associated with severe symptoms were significantly more elevated than those associated with mild to moderate symptoms . Studies are under way to determine expression of P . aeruginosa exotoxin A by detecting quantitatively levels of the translated exotoxin A protein produced by isolates associated with severe and mild to moderate symptoms. J Altern Complement Med, 2002 Aug, 8(4), 459 - 66 Gerimax ginseng regulates both humoral and cellular immunity during chronic Pseudomonas aeruginosa lung infection; Song Z et al.; BACKGROUND: Chronic lung infection among patients with cystic fibrosis (CF), diffused panbronchiolitis, and chronic obstructive bronchiecteisis is often because of Pseudomonas aeruginosa . High morbidity and mortality in patients with CF are because of P . aeuruginosa that undergoes genotypic and phenotypic changes during prolonged stay in the lung resulting in increased antibiotic resistance, necessitating a search for alternative or supplement drugs . OBJECTIVE: In this study we compared the therapeutical effect of Gerimax (Dansk Droge A/S, Ishoj, Denmark) ginseng with placebo control by using a rat model of chronic P . aeruginosa lung infection mimicking that in patients with CF . METHODS AND INTERVENTIONS: The animals were challenged intratracheally with the prototypic P . aeruginosa PAO1 in alginate beads (1 x 10(9) colony-forming units per milliliter {CFU/mL}) followed by subcutaneous injection of ginseng extract (150 mg/kg body weight once per day) and examined on days 7 and 21 . RESULTS: The day 7 analyses show that ginseng treatment resulted in lowering serum immunoglobulin M (IgM) and lung interleukin-4 (IL-4) levels compared to the control group . On day 21, higher lung IgA, upregulated serum IgG2a, stronger lung responses of interferon-gamma, IL-4, and tumor necrosis factor-alpha with milder lung pathology and enhanced lung bacteriology were detected in the ginseng-treated group when compared to those of the control group . CONCLUSION: These results suggest that the Gerimax ginseng treatment can modulate the immune system in favor of clearing the infection with P . aeruginosa in the lungs of rats . Thus, ginseng might be a promising alternative supplement for the treatment of chronic P . aeruginosa lung infection in patients with CF. Chest, 2002 Sep, 122(3), 930 - 4 Evaluation of bronchial constriction in children with cystic fibrosis after inhaling two different preparations of tobramycin; Alothman GA et al.; OBJECTIVES: This randomized, double-blind, cross-over study evaluated the risk of bronchoconstriction with two preparations of inhaled tobramycin in children with cystic fibrosis (CF) infected with Pseudomonas aeruginosa with and without airway hyperreactivity . DESIGN: Of 19 children with CF (age range, 7 to 16 years) with mild-to-moderate pulmonary disease, 10 children were at high risk (HR) for bronchospasm (family history of asthma and previous response to bronchodilators) and 9 children were at low risk (LR) for bronchospasm (no family history of asthma or previous response to bronchodilators) . Two solutions of tobramycin were administered: (1) 80 mg in a 2-mL vial diluted with 2 mL of saline solution containing the preservatives phenol and bisulfites (IV preparation); and (2) 300 mg in a preservative-free preparation in a 5-mL solution . Following a bronchodilator-free period of 12 h, the patients inhaled either one or the other preparation in random order on two different occasions, 2 weeks apart . RESULTS: Prechallenge and postchallenge results for the LR group showed a percentage of fall in FEV(1) (DeltaFEV(1)) of 12 +/- 9% (mean +/- SD) for the IV preparation, compared to 4 +/- 5% for the preservative-free preparation (p = 0.046) . An DeltaFEV(1) of > 10% was seen in six of nine patients for the IV preparation and in one of nine patients for preservative-free preparation . For the HR group, the DeltaFEV(1) was 17 +/- 13% for the IV-preparation group, compared to 16 +/- 12% for the preservative-free group (p = 0.4) . In this group, equal numbers of patients (8 of 10 patients) had an DeltaFEV(1) > 10% after inhaling each preparation . The largest DeltaFEV(1) was 44% (HR group with the preservative-free preparation that forced the early termination of inhalation) . CONCLUSIONS: Both preparations caused significant bronchoconstriction in the HR group, and the preservative-containing IV preparation caused more bronchospasm in LR group than the preservative-free solution . Heightened airway reactivity in children with CF places them at risk of bronchospasm from inhalation therapy. Microb Pathog, 2002 Sep, 33(3), 135 - 43 Mutation of csk, encoding the C-terminal Src kinase, reduces Pseudomonas aeruginosa internalization by mammalian cells and enhances bacterial cytotoxicity; Evans DJ et al.; Clinical isolates of Pseudomonas aeruginosa are either invasive or cytotoxic towards mammalian epithelial cells, endothelial cells, and macrophages . Invasion requires host cell actin cytoskeleton function, and ExsA-regulated proteins of P . aeruginosa that inhibit invasion (ExoS and ExoT) can disrupt the cytoskeleton . Another ExsA regulated protein, ExoU, is involved in the cytotoxic activity of cytotoxic strains . Src-family kinases are thought to participate in the regulation of cytoskeleton function . Recent studies have suggested that Src-family tyrosine kinases, p60-Src and p59-Fyn, are activated during P . aeruginosa invasion . Using fibroblasts homozygous for mutation of csk (-/-), we tested the hypothesis that mutation of csk, encoding a negative regulator of Src-family tyrosine kinases, would be important in P . aeruginosa invasion and cytotoxicity . Mutation of csk was found to reduce invasion by approximately 8-fold, without reducing bacterial adherence to cells (P=0.0001) . Conversely, csk (-/-) cells were approximately 5-fold more susceptible to ExoU-dependent cytotoxicity (P=0.024), which was accompanied by a small increase in ExsA-regulated adherence . ExoT-dependent invasion inhibitory activity of cytotoxic P . aeruginosa was attenuated in csk (-/-) cells as compared to normal fibroblasts . These data show that fibroblasts, like epithelial cells, are susceptible to P . aeruginosa invasion and cytotoxicity . They also show a role for Csk in P . aeruginosa invasion, while providing further evidence that actin cytoskeleton disruption contributes to ExsA-regulated P . aeruginosa cytotoxicity and invasion inhibition. Microb Pathog, 2002 Sep, 33(3), 109 - 14 Pseudomonas aeruginosa outer membrane protein F is an adhesin in bacterial binding to lung epithelial cells in culture; Azghani AO et al.; Adherence to host cells is a crucial step by which bacteria initiate an infection but the bacterial determinants of the process are, as yet, poorly understood . In an effort to identify bacterial adhesins responsible for Pseudomonas aeruginosa binding to host cells, we identified porin F (OprF) from the outer membrane of P . aeruginosa as adhesin for human alveolar epithelial (A549) cells . Bacterial adhesion assays with (35)S-labeled wild type P . aeruginosa and its isogenic mutant strain lacking OprF showed that the mutant strain binds 43% less than the wild type to A549 cells (P<0.01) . In addition, bacterial binding is significantly reduced (P<0.01) when either A549 cells were pretreated with purified OprF or if bacteria were pre-incubated with a monoclonal antibody to OprF . Finally, ligand binding experiments in which purified OprF protein was added to A549 monolayers showed saturable binding . These data indicate that OprF contributes to bacterial adherence to A549 epithelial cells and could facilitate Pseudomonas interactions with the epithelium, including colonization of the airway epithelium or the initiation of pulmonary infection. BMC Urol . 2002 Sep 10;2(1):9. How should an infected perinephric haematoma be drained in a tetraplegic patient with baclofen pump implanted in the abdominal wall? - A case report; Vaidyanathan S et al.; BACKGROUND: We present a case to illustrate controversies in percutaneous drainage of infected, perinephric haematoma in a tetraplegic patient, who had implantation of baclofen pump in anterior abdominal wall on the same side as perinephric haematoma . CASE PRESENTATION: A 56-year-old male with C-4 tetraplegia had undergone implantation of programmable pump in the anterior abdominal wall for intrathecal infusion of baclofen to control spasticity . He developed perinephric haematoma while he was taking warfarin as prophylactic for deep vein thrombosis . Perinephric haematoma became infected with a resistant strain of Pseudomonas aeruginosa, and required percutaneous drainage . Positioning this patient on his abdomen without anaesthesia, for insertion of a catheter from behind, was not a realistic option . Administration of general anaesthesia in this patient in the radiology department would have been hazardous . RESULTS AND CONCLUSION: Percutaneous drainage was carried out by anterior approach under propofol sedation . The site of entry of percutaneous catheter was close to cephalic end of baclofen pump . By carrying out drainage from anterior approach, and by keeping this catheter for ten weeks, we took a risk of causing infection of the baclofen pump site, and baclofen pump with a resistant strain of Pseudomonas aeruginosa . The alternative method would have been to anaesthetise the patient and position him prone for percutaneous drainage of perinephric collection from behind . This would have ensured that the drainage track was far away from the baclofen pump with minimal risk of infection of baclofen pump, but at the cost of incurring respiratory complications in a tetraplegic subject. J Am Anim Hosp Assoc, 2002 Sep-Oct, 38(5), 407 - 13 Frequency of isolation and antimicrobial susceptibility patterns of Staphylococcus intermedius and Pseudomonas aeruginosa isolates from canine skin and ear samples over a 6-year period (1992-1997); Petersen AD et al.; Staphylococcus intermedius (S . intermedius) was isolated from 88.6% and 49.4% of skin and ear samples, respectively, during the years 1992 through 1997, and frequency of isolation remained unchanged . More than 95% of all S . intermedius isolates were susceptible to cephalothin and oxacillin, providing support for empirical treatment of canine skin and ear infections with cephalexin . Pseudomonas aeruginosa (P . aeruginosa) was isolated from 7.5% and 27.8% of skin and ear samples, respectively . The frequency of isolation from skin samples increased over the study period . Because of multidrug-resistant profiles for P . aeruginosa isolates, especially for ear isolates, empirical treatment of P . aeruginosa infections is not advisable. Hunan Yi Ke Da Xue Xue Bao, 2000 Aug 28, 25(4), 388 - 90 {Clinical study on nosocomial infection in patients with burns}; Yang XH et al.; OBJECTIVE: To study clinical characters and related factors of nosocomial infection in patients with burns . METHODS: To study 782 cases of burns as a group hospitalized in our department for more than 48 h, from January, 1993 to December, 1996 . Prospective and retrospective investigation of infection locations, infection rates, pathogen and drug sensibility was carried out . RESULTS: The infection most often found in blood and wound, less often in respiratory system . Nosocomial infection rates in patients with burns were closely related to the severe degree, diagnosis and therapy of these patients and hospital surroundings . Infection bacteria species: Gram-positive bacterium accounted for 43.82%, and mainly were staphylococcus aureus and anaerobic peptococcus . Gram-negative bacterium accounted for 52.81%, of which pseudomonas aeruginosa and nitrate-negative bacillus constituted the majority . CONCLUSION: According to these characters and related factors of nosocomial infection in patients with burns, effective measures of preventing and controlling infection should be taken, so that the incidence of nosocomial infection in these patients will drop. Chemotherapy, 2002 Sep, 48(4), 182 - 8 Postantibiotic effect of meropenem and ciprofloxacin in the presence of 5-fluorouracil; Nyhlen A et al.; BACKGROUND: The postantibiotic effect (PAE) of meropenem and ciprofloxacin was studied in the presence of the antineoplastic agent 5-fluorouracil (5-FU) . The purpose of the study was to investigate whether the PAEs of the combinations differed from the PAEs of the antibiotics alone . METHODS: The PAEs of the combinations of 5-FU plus meropenem or ciprofloxacin were determined with viable counts against four reference strains of Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Escherichia coli and two clinical isolates of S . epidermidis . The results were compared with the PAEs of the antibiotics drugs and 5-FU alone . The gram-positive strains were tested for slime production, both alone and in the presence of 5-FU . RESULTS: Against two of the three tested strains of S . epidermidis, the combination of ciprofloxacin and 5-FU gave a synergistic prolongation of the PAE in comparison with the PAEs induced by the drugs alone . The combinations showed indifference against the other bacteria . The combination of meropenem and 5-FU had a synergistic PAE against one of the three tested strains of S . epidermidis and an additive effect against E . coli but showed indifference against the rest of the strains . CONCLUSIONS: The presence of 5-FU did not influence the PAEs of the antibiotics against most of the tested strains, but caused a synergistic prolongation of the PAEs induced by ciprofloxacin and meropenem against some of the tested strains of S . epidermidis . 5-FU inhibited slime production in the same S . epidermidis strains, which might have contributed to the longer PAE . Chemotherapy, 2002 Sep, 48(4), 164 - 7 Comparative study of antimicrobial resistance of Pseudomonas aeruginosa strains isolated from patients of Caracas and Asunción in a 4-year-period; Rodriguez AJ et al.; The antimicrobial resistance of Pseudomonas aeruginosa to beta-lactams, aminoglycosides and ciprofloxacin was investigated in two Latin American hospitals, one in Venezuela and the other in Paraguay . The resistance of P . aeruginosa was investigated in 1,481 clinically isolated strains, 988 from Asuncion and 493 from Caracas, collected between 1996 and 1999 . Susceptibility was assessed by the disk diffusion method according to the National Committee for Clinical Laboratory Standards . 11.4% were resistant to cefoperazone, 11.4% to ceftazidime, 12.8% to piperacillin, 13.6% to amikacin, 18.2% to gentamicin, 11.1% to ciprofloxacin, and 6.7% to imipenem . There were significant differences in resistance patterns between isolates from Asuncion and Caracas . Resistance was higher in Caracas . Despite similar antibiotic usage policies and other measures, differences in the resistance patterns of P . aeruginosa are evident in this study . The clinical and therapeutic implications of this resistance suggest the need to maintain surveillance in local settings, especially in developing countries such as Venezuela and Paraguay . J Bacteriol, 2002 Oct, 184(19), 5251 - 60 FleQ, the major flagellar gene regulator in Pseudomonas aeruginosa, binds to enhancer sites located either upstream or atypically downstream of the RpoN binding site; Jyot J et al.; In Pseudomonas aeruginosa, flagellar genes are regulated in a cascade headed by FleQ, an NtrC/NifA-type activator . FleQ and RpoN positively regulate expression of flhA, fliE, fliL, and fleSR genes, among others . Direct interaction of FleQ with flhA, fliE, fliL, and fleSR promoters was demonstrated by gel shift assay, along with experiments to conclusively determine the specificity of its binding . DNase I footprinting was performed to determine the FleQ binding sites on flhA, fliE, fliL, and fleSR promoters . No sequence conservation among these binding sites was observed . Primer extension analysis revealed the transcription start sites (TSSs) to be localized above the FleQ binding sites in flhA, fliE, and fliL promoters . Analysis of the above data revealed FleQ binding to be in the leader sequence of these promoters, whereas FleQ binding was 67 bp upstream of the TSS in the fleSR promoter . Mutagenesis of the FleQ binding site in the flhA promoter confirmed its functionality in vivo . Deletion of the flhA promoter upstream of the RNA polymerase binding site did not result in a significant loss of promoter activity . These results point to two modes of regulation by an NtrC-type regulator in the flagellar hierarchy in P . aeruginosa, the first being the typical model of activation from a distance via looping in the fleSR promoter and the second involving flhA, fliE, and fliL promoters, where FleQ binds in the downstream vicinity of the promoter and activates transcription without looping. J Bacteriol, 2002 Oct, 184(19), 5240 - 50 fleQ, the gene encoding the major flagellar regulator of Pseudomonas aeruginosa, is sigma70 dependent and is downregulated by Vfr, a homolog of Escherichia coli cyclic AMP receptor protein; Dasgupta N et al.; The flagellar transcriptional regulator FleQ appears to be the highest-level regulator in the hierarchical regulatory cascade of flagellar biogenesis in Pseudomonas aeruginosa . Except for the posttranslational downregulation of FleQ activity by FleN, an antiactivator, not much is known about the regulation of the fleQ gene or its gene product . Some FleQ homologs in other bacterial species either are positively regulated by another regulator (e.g., CtrA, the master regulator regulating FlbD in Caulobacter crescentus) or are expressed from a sigma70-dependent promoter (e.g., FlgR of Helicobacter pylori) . In this study we demonstrated that Vfr, an Escherichia coli CRP homolog known to function as an activator for various genes, including lasR, regA, and toxA, in P . aeruginosa, is capable of repressing fleQ transcription by binding to its consensus sequence in the fleQ promoter . In a DNase I footprint assay, purified Vfr protected the sequence 5'-AATTGACTAATCGTTCACATTTG-3' . When this putative Vfr binding site in the fleQ promoter was mutated, Vfr was unable to bind the fleQ promoter fragment and did not repress fleQ transcription effectively . Primer extension analysis of the fleQ transcript revealed two transcriptional start sites, t1 and t2, that map within the Vfr binding site . A putative -10 region (TAAAAT) for the t2 transcript, with a five-of-six match with the E . coli sigma70 binding consensus, overlaps with one end of the Vfr binding site . A 4-bp mutation and an 8-bp mutation in this -10 region markedly reduced the activity of the fleQ promoter . The same mutations led to the disappearance of the 203-nucleotide fleQ transcript in an in vitro transcription assay . Vfr probably represses fleQ transcription by binding to the Vfr binding site in the fleQ promoter and preventing the sigma factor from binding to the -10 region to initiate transcription. Bioorg Med Chem, 2002 Nov, 10(11), 3489 - 98 Design, synthesis, and biological evaluation of a series of beta-lactam-based prodrugs; Hakimelahi GH et al.; By use of pro-dual-drug concept the synthesis of 6-beta-{(R)-2-(clavaminio-9-N-yl)-2-(4-hydroxyphenylacetamido)}penicillanic acid (10), 6-beta-{(R)-2-(amino)-2-(4-(clavulano-9-O-yl)phenylacetamido)}penicillanic acid (13), (Z)-4-{2-(amoxycillin-4-O-yl)ethylidene}-2-(clavulano-9-O-yl)-3-methoxy-Delta(alpha,beta)-butenolide (19), and 3-{(amoxicillin-4-O-yl)methyl}-7-(phenoxyacetamido)-(1-oxo)-3-cephem-4-carboxylic acid (23) was accomplished . Unlike penicillin G, ampicillin, or amoxicillin, these four heretofore undescribed compounds 10, 13, 19, and 23 showed notable activity against beta-lactamase (betaL) producing microorganisms, Staphylococcus aureus A9606, S . aureus A15091, S . aureus A20309, S . aureus 95, Escherichia coli A9675, E . coli A21223, E . coli 27C7, Pseudomonas aeruginosa 18S-H, and Klebsiella pneumoniae A20634 TEM . In comparison with amoxicillin (9), alpha-amino-substituted compound 10 and butenolide derivative 19 showed a broadened spectrum of antibacterial activity; yet they were found to be less active than 13 and 23 . Like clavulanic acid (7) or cephalosporin-1-oxide (21), the newly synthesized compounds 10, 13, 15, 16, 19, or 23 functioned as potent inhibitors of various bacterial betaLs. J Pept Sci, 2002 Aug, 8(8), 431 - 7 Antimicrobial activity of short arginine- and tryptophan-rich peptides; Strom MB et al.; Highly antimicrobial active arginine- and tryptophan-rich peptides were synthesized ranging in size from 11 to five amino acid residues in order to elucidate the main structural requirement for such short antimicrobial peptides . The amino acid sequences of the peptides were based on previous studies of longer bovine and murine lactoferricin derivatives . Most of the peptides showed strong inhibitory action against the Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa, and the Gram-positive bacterium Staphylococcus aureus . For the most active derivatives, the minimal inhibitory concentration values observed for the Gram-negative bacteria were 5 microg/ml (3.5 microM), whereas it was 2.5 microg/ml (1.5 microM) for the Gram-positive bacterium . It was essential for the antimicrobial activity that the peptides contained a minimum of three tryptophan and three arginine residues, and carried a free N-terminal amino group and an amidated C-terminal end . Furthermore, a minimum sequence size of seven amino acid residues was required for a high antimicrobial activity against Pseudomonas aeruginosa . The insertion of additional arginine and tryptophan residues into the peptides resulted only in small variations in the antimicrobial activity, whereas replacement of a tryptophan residue with tyrosine in the hepta- and hexapeptides resulted in reduced antimicrobial activity, especially against the Gram-negative bacteria . The peptides were non-haemolytic, making them highly potent as prospective antibiotic agents. Kansenshogaku Zasshi, 2002 Jul, 76(7), 576 - 80 {A case of Pseudomans aeruginosa pneumonia complicated with multiple pustular skin lesions}; Miyajima Y et al.; Pseudomonas aeruginosa is a common causative agent of septicemia in compromised host and the entry site of organism is most commonly the respiratory and genitourinary tract . P . aeruginosa septicemia is often associated with vesicular or pustular skin lesions, subcutaneous nodules, deep abscess, cellulites and bullae . We report a case of P . aeruginosa pneumonia with multiple pustular skin lesions on the chest and leg . A 77-year-old male was admitted to our hospital complaining of fever, productive cough and eruptions . Laboratory findings revealed a leucocytosis (14,830/microliter) and an elevated CRP (21.72 mg/dl) . The chest radiograph and computed tomography revealed a fluid level in preexisting bullae and a consolidation shadow with multiple cavities in the right upper lobe and nodular shadow with cavity in the left lower lobe . P . aeruginosa strain was isolated from the bronchial lavage and pustule . Blood cultures were negative . Skin biopsy specimens showed histologically a dense infiltrate of neutrophils in the horny cell layer . He was diagnosed as Pseudomonas aeruginosa pneumonia complicated with multiple pustular skin lesions . He was treated with antimicrobial agents for 24 days and his clinical condition improved. Mol Microbiol, 2002 Sep, 45(5), 1277 - 87 GeneChip expression analysis of the iron starvation response in Pseudomonas aeruginosa: identification of novel pyoverdine biosynthesis genes; Ochsner UA et al.; Upon iron restriction, the opportunistic pathogen Pseudomonas aeruginosa produces various virulence factors, including siderophores, exotoxin, proteases and haemolysin . The ferric uptake regulator (Fur) plays a central role in this response and also controls other regulatory genes, such as pvdS, which encodes an alternative sigma factor . This circuit leads to a hierarchical cascade of direct and indirect iron regulation . We used the GeneChip to analyse the global gene expression profiles in response to iron . In iron-starved cells,the expression of 118 genes was increased at least fivefold compared with that in iron-replete cells, whereas the expression of 87 genes was decreased at least fivefold . The GeneChip data correlated well with results obtained using individual lacZ gene fusions . Strong iron regulation was observed for previously identified genes involved in biosynthesis or uptake of the siderophores pyoverdine and pyochelin, utilization of heterologous siderophores and haem and ferrous iron transport . A low-iron milieu led to increased expression of the genes encoding TonB, alkaline protease,PrpL protease, exotoxin A, as well as fumarase C, Mn-dependent superoxide dismutase SodA, a ferredoxin and ferredoxin reductase and several oxidoreductases and dehydrogenases . Iron-controlled regulatory genes included seven alternative sigma factors and five other transcriptional regulators . Roughly 20% of the iron-regulated genes encoded proteins of unknown function and lacked any conclusive homologies . Under low-iron conditions, expression of 26 genes or operons was reduced in a DeltapvdS mutant compared with wild type, including numerous novel pyoverdine biosynthetic genes . The GeneChip proved to be a very useful tool for rapid gene expression analysis and identification of novel genes controlled by Fur or PvdS. Mol Microbiol, 2002 Sep, 45(5), 1177 - 90 Iron transport and regulation, cell signalling and genomics: lessons from Escherichia coli and Pseudomonas; Visca P et al.; A variety of bacterial species secrete and take up chelating compounds that enable acquisition of iron (siderophores) . It has become clear that a common feature in regulation of different iron acquisition systems is the involvement of alternative sigma factor proteins of the extracytoplasmic function (ECF) family . Two of these proteins, PvdS from Pseudomonas aeruginosa and FecI from Escherichia coli K-12, have been studied extensively . PvdS directs transcription of genes required for the biosynthesis of a siderophore, pyoverdine, and FecI causes expression of genes for uptake of ferric citrate . FecI forms part of a signalling system that responds to the presence of ferric citrate . Here, we review recent advances in understanding of PvdS and of the Fec signalling system . PvdS and FecI are part of a distinct subfamily of ECF sigma factors involved in iron acquisition and hence named the iron-starvation sigmas . Analysis of microbial genome sequences shows that Fec-like signalling systems are present in a wide range of species and many such systems may be present in a single species . The availability of tools for large-scale genome analysis is likely to lead to rapid advances in our understanding of this expanding family of proteins. Pediatr Pulmonol, 2002 Oct, 34(4), 257 - 61 Transmission of colistin-resistant Pseudomonas aeruginosa between patients attending a pediatric cystic fibrosis center; Denton M et al.; We report on an outbreak of colistin-resistant Pseudomonas aeruginosa (CRPA) that occurred in a United Kingdom pediatric cystic fibrosis (CF) unit and involved six children over a period of 5 years . All CRPA-positive children had received aerosolized colistin therapy before first isolation of resistant organisms (mean duration, 3.1 years) . Four of the 6 had also received courses of intravenous colistin in the year before the first isolation of CRPA . No impact of CRPA acquisition on respiratory function, clinical condition, or radiological parameters could be demonstrated . Four of the 6 children carried isolates of CRPA indistinguishable on genotyping . Two of these 4 children were sisters . The other 2 were on the same ward together at time of first isolation, and subsequently shared overlapping admissions with one of the sisters.While there is no conclusive evidence for the route of transmission, the frequency of overlapping in-patient admissions between 3 of these patients is suggestive of patient-to-patient transfer in the nosocomial setting.CF clinicians should be aware that colistin resistance can occur in P . aeruginosa, and some of these strains are capable of spread within CF units . Pediatr Pulmonol, 2002 Sep, 34(3), 232 - 6 Early infection and progression of cystic fibrosis lung disease; Koch C; Chronic Pseudomonas aeruginosa infection is the major limitation in overall survival of patients with cystic fibrosis, and elective bronchoscopy shows that infection with this organism starts at a very early age . Early infection with nonmucoid P . aeruginosa gradually develops into chronic infection, characterized by the presence of microcolonies of alginate-producing (mucoid) P . aeruginosa in the bronchial tree . Chronic infection cannot be cured, but aggressive antimicrobial treatment will prolong life expectancy and decrease morbidity . It has, however, over the last decade become evident that early antimicrobial treatment of the initial infection with nonmucoid strains can prevent or at least postpone transition into chronic (mucoid) infection . This treatment strategy is likely to dramatically improve the prognosis of patients with cystic fibrosis in the immediate future . Anal Chem, 2002 Aug 15, 74(16), 4290 - 3 Simultaneous multiple substrate tag detection with ESI-ion trap MS for in vivo bacterial enzyme activity profiling; Basile F et al.; A bacterial identification method in which multiple enzyme activities are measured simultaneously and in vivo with electrospray ionization-mass spectrometry (ESI-MS) is described . Whole-cell bacteria are immobilized onto a filter support and incubated with a mixture of substrates . Each substrate is chosen to measure a specific enzyme activity of a targeted bacterium and to produce a tag of unique molecular weight . After a predetermined incubation time, the solution is filtered, and the supernatant consisting of a mixture of released tags and unhydrolyzed substrates is directly analyzed, without chromatographic separation, by ESI-MS . Bacteria remain viable on the filter for further analyses . The method was tested by measuring the aminopeptidase activity of the bacteria Escherichia coli, Bacillus subtilis, Bacillus cereus, and Pseudomonas aeruginosa . The resulting aminopeptidase enzyme profiles allowed the differentiation between the four bacteria tested . The method is rapid, since a multiplex advantage is realized when assaying for multiple enzymes, and it is amenable to automation via a flow injection analysis setup. Biochem Soc Trans, 2002 Aug, 30(4), 702 - 5 A new mechanism for membrane iron transport in Pseudomonas aeruginosa; Schalk IJ et al.; Various biochemical and biophysical studies have demonstrated the existence of a novel iron-uptake mechanism in Pseudomonas aeruginosa, different from that generally described for ferrichrome and ferric-enterobactin in Escherichia coli . This new iron-uptake mechanism involves all the proteins generally reported to be involved in the uptake of ferric-siderophore complexes in Gram-negative bacteria (i.e . the outer membrane receptor, periplasmic binding protein and ATP-binding-cassette transporter), but differs in the behaviour of the siderophore . One of the key features of this process is the binding of iron-free pyoverdin to the outer membrane receptor FpvA in conditions of iron deficiency. Arch Intern Med, 2002 Sep 9, 162(16), 1849 - 58 Community-acquired pneumonia due to gram-negative bacteria and pseudomonas aeruginosa: incidence, risk, and prognosis; Arancibia F et al.; BACKGROUND: Initial empirical antimicrobial treatment of patients with community-acquired pneumonia (CAP) is based on expected microbial patterns . We determined the incidence of, prognosis of, and risk factors for CAP due to gram-negative bacteria (GNB), including Pseudomonas aeruginosa . METHODS: Consecutive patients with CAP hospitalized in our 1000-bed tertiary care university teaching hospital were studied prospectively . Independent risk factors for CAP due to GNB and for death were identified by means of stepwise logistic regression analysis . RESULTS: From January 1, 1997, until December 31, 1998, 559 hospitalized patients with CAP were included . Sixty patients (11%) had CAP due to GNB, including P aeruginosa in 39 (65%) . Probable aspiration (odds ratio {OR}, 2.3; 95% confidence interval {CI}, 1.02-5.2; P =.04), previous hospital admission (OR, 3.5; 95% CI, 1.7-7.1; P<.001), previous antimicrobial treatment (OR, 1.9; 95% CI, 1.01-3.7; P =.049), and the presence of pulmonary comorbidity (OR, 2.8; 95% CI, 1.5-5.5; P =.02) were independent predictors of GNB . In a subgroup analysis of P aeruginosa pneumonia, pulmonary comorbidity (OR, 5.8; 95% CI, 2.2-15.3; P<.001) and previous hospital admission (OR, 3.8; 95% CI, 1.8-8.3; P =.02) were predictive . Infection with GNB was independently associated with death (relative risk, 3.4; 95% CI, 1.6-7.4; P =.002) . CONCLUSIONS: In our setting, in every tenth patient with CAP, an etiology due to GNB has to be considered . Patients with probable aspiration, previous hospitalization or antimicrobial treatment, and pulmonary comorbidity are especially prone to GNB . These pathogens are also an independent risk factor for death in patients with CAP. Eye, 2002 Sep, 16(5), 608 - 18 Incidence and risk factors for microbial keratitis in Hong Kong: comparison with Europe and North America; Lam DS et al.; PURPOSE: To establish the incidence, etiology and risk factors for microbial keratitis (MK) in Hong Kong . METHODS: Two hundred and twenty-three new cases of presumed MK were recruited over a period of 17 months and comprehensive microbiologic studies performed . A nested case-control study was pursued for patients wearing contact lenses (CLW) to determine risk factors for MK with regards to types of CLW and hygiene practice . RESULTS: Of the 223 patients recruited, 59 (26%) wore contact lenses . Corneal scrapes yielded positive cultures from 77 patients (35% overall, 56 non-CLW, 21 CLW) . Two hundred and six CLW volunteers were recruited to participate in the case-control study, of whom 135 were matched with 45 CLW patients . The annual incidence of MK was 0.63 per 10,000 population and 3.4 per 10,000 CLW with rates for daily, extended and rigid lens wear of 3.09, 9.30 and 0.44 per 10,000 CLW respectively . Pseudomonas aeruginosa was the dominant bacterial pathogen . Six cases of Acanthamoeba keratitis occurred, five in CLW (incidence 0.33 per 10,000 CLW) and one following corneal abrasion . Non-CLW developed MK at a peak age of 73, which is 10 years younger than expected for Scotland and USA . CONCLUSIONS: Previous ocular surface disease and trauma were the main risk factors for MK in Hong Kong . CLW appears at least as safe as that found in Scotland and the USA . Acanthamoeba keratitis was detected but with an incidence rate five times lower than Scotland . Factors predisposing hydrogel CLWs to MK, that were statistically significant, included overnight wear, poor hygiene and smoking. J Immunol, 2002 Sep 1, 169(5), 2636 - 42 The Pseudomonas autoinducer N-(3-oxododecanoyl) homoserine lactone induces cyclooxygenase-2 and prostaglandin E2 production in human lung fibroblasts: implications for inflammation; Smith RS et al.; Pseudomonas aeruginosa causes lethal lung infections in immunocompromised individuals such as those with cystic fibrosis . The lethality of these infections is directly associated with inflammation and lung tissue destruction . P . aeruginosa produces several acylated homoserine lactones (AHL) that are important in the regulation of bacterial virulence factors . Little is known about the effects of AHLs on human cells . In this work we report that the AHL N-(3-oxododecanoyl) homoserine lactone (3O-C(12)-HSL) from P . aeruginosa induces cyclooxygenase (Cox)-2, a seminal proinflammatory enzyme . When primary normal human lung fibroblasts were exposed to 3O-C(12)-HSL, an 8-fold induction in mRNA and a 35-fold increase in protein for Cox-2 were observed . In contrast, there was no substantial change in the expression of Cox-1 . We also demonstrated that the induction of Cox-2 was regulated by 3O-C(12)-HSL activation of the transcription factor NF-kappaB . 3O-C(12)-HSL also stimulated an increase in the newly discovered inducible membrane-associated PGE synthase but had no effect on the expression of the cytosolic PGE synthase . We also demonstrate that 3O-C(12)-HSL stimulated the production of PGE(2) . PGE(2) is known to induce mucus secretion, vasodilation, and edema, and acts as an immunomodulatory lipid mediator . We propose that 3O-C(12)-HSL induction of Cox-2, membrane-associated PGE synthase, and PGE(2) likely contributes to the inflammation and lung pathology induced by P . aeruginosa infections in the lung . These studies further reinforce the concept that bacterial AHLs not only regulate bacterial virulence but also stimulate the activities of eukaryotic cells important for inflammation and immune defenses. J Bacteriol, 2002 Sep, 184(18), 5036 - 44 The MexJK efflux pump of Pseudomonas aeruginosa requires OprM for antibiotic efflux but not for efflux of triclosan; Chuanchuen R et al.; Using the biocide triclosan as a selective agent, several triclosan-resistant mutants of a susceptible Pseudomonas aeruginosa strain were isolated . Cloning and characterization of a DNA fragment conferring triclosan resistance from one of these mutants revealed a hitherto uncharacterized efflux system of the resistance nodulation cell division (RND) family, which was named MexJK and which is encoded by the mexJK operon . Expression of this operon is negatively regulated by the product of mexL, a gene located upstream of and transcribed divergently from mexJK . The triclosan-resistant mutant contained a single nucleotide change in mexL, which caused an amino acid change in the putative helix-turn-helix domain of MexL . The MexL protein belongs to the TetR family of repressor proteins . The MexJK system effluxed tetracycline and erythromycin but only in the presence of the outer membrane protein channel OprM; OprJ and OprN did not function with MexJK . Triclosan efflux required neither of the outer membrane protein channels tested but necessitated the MexJ membrane fusion protein and the MexK inner membrane RND transporter . The results presented in this study suggest that MexJK may function as a two-component RND pump for triclosan efflux but must associate with OprM to form a tripartite antibiotic efflux system . Furthermore, the results confirm that triclosan is an excellent tool for the study of RND multidrug efflux systems and that this popular biocide therefore readily selects mutants which are cross-resistant with antibiotics. Hosp Med, 2002 Jul, 63(7), 421 - 5 TOBI: reducing the impact of pseudomonal infection; Govan J; Pseudomonas aeruginosa infection is associated with impaired lung function and reduced life expectancy in cystic fibrosis patients . Tobramycin nebulizer solution (TOBI, Chiron Corporation Ltd, Hounslow) has been specifically formulated for use against P . aeruginosa infection in the lung. Infect Control Hosp Epidemiol, 2002 Aug, 23(8), 441 - 6 An outbreak of multidrug-resistant Pseudomonas aeruginosa associated with increased risk of patient death in an intensive care unit; Bukholm G et al.; OBJECTIVE: To investigate an outbreak of multidrug-resistant Pseudomonas aeruginosa in an intensive care unit (ICU) . DESIGN: Epidemiologic investigation, environmental assessment, and ambidirectional cohort study . SETTING: A secondary-care university hospital with a 10-bed ICU . PATIENTS: All patients admitted to the ICU receiving ventilator treatment from December 1, 1999, to September 1, 2000 . RESULTS: An outbreak in an ICU with multidrug-resistant isolates of P aeruginosa belonging to one amplified fragment-length polymorphism (AFLP)-defined genetic cluster was identified, characterized, and cleared . Molecular typing of bacterial isolates with AFLP made it possible to identify the outbreak and make rational decisions during the outbreak period . The outbreak included 19 patients during the study period . Infection with bacterial isolates belonging to the AFLP cluster was associated with reduced survival (odds ratio, 5.26; 95% confidence interval, 1.14 to 24.26) . Enhanced barrier and hygiene precautions, cohorting of patients, and altered antibiotic policy were not sufficient to eliminate the outbreak . At the end of the study period (in July), there was a change in the outbreak pattern from long (December to June) to short (July) incubation times before colonization and from primarily tracheal colonization (December to June) to primarily gastric or enteral July) colonization . In this period, the bacterium was also isolated from water taps . CONCLUSION: Complete elimination of the outbreak was achieved after weekly pasteurization of the water taps of the ICU and use of sterile water as a solvent in the gastric tubes. Med Dosw Mikrobiol, 2002, 54(1), 61 - 6 {The effect of culture conditions on hydrophobic properties of Pseudomonas aeruginosa}; Wolska K et al.; The cell surface hydrophobicity (CSH) plays an important role in a adhesion of bacteria on solid surfaces . CSH of 62 Pseudomonas aeruginosa strains isolated from humans and different animals was assessed using the ammonium sulfate salt aggregation test . Bacteria were grown for 24 h and 48 h at a room temperature (22 degrees C) and 37 degrees C on enrichment broth and agar (Biomed) and tryptic soy agar (Difco) . The hydrophobic properties of the Pseudomonas aeruginosa strains were depended on the temperature, time of the culture of bacteria and the kind of media . CSH properties were most frequently expressed when the analyzed strains were cultured in enrichment broth . In a such conditions Pseudomonas aeruginosa strains were more hydrophobic when grown at 22 degrees C (94% after 24 h and 87% after 48%) than those at 37 degrees C (72% after 24 h and 71% after 48 h) . Among strains cultured in tryptic soy agar at 37 degrees C, 48% after 24 h and 75% after 48 h were autoaggregating, representing very strong hydrophobic properties. Br J Ophthalmol, 2002 Sep, 86(9), 975 - 7 The use of surgical facemasks during cataract surgery: is it necessary? Alwitry A, Jackson E, Chen H, Holden R. AIM: To assess whether facemask utilisation by the surgeon during cataract surgery has any effect on the bacterial load falling onto the operative site . METHOD: Prospective randomised masked study . Consent was obtained from 221 patients . Cases were randomised to wearing a new mask or not wearing any mask throughout the procedure . Blood agar settle plates were placed adjacent to the patient's head in the operative field . Duration of procedure was noted . Plates were incubated and read at 48 hours . Colony forming bacteria were counted and identified . RESULTS: There were significantly fewer organisms cultured when the surgeon used a facemask (p=0.0006) . The majority of organisms were Staphylococcus epidermidis, Bacillus spp, and Diphtheroid spp; however Staphylococcus aureus and Pseudomonas aeruginosa were cultured on several occasions . There were no cases of infective complication . CONCLUSIONS: The main purpose of an operating mask is to prevent bacteria falling on to the operative site from the surgeon's oropharynx or nasopharynx with the concomitant theoretical risk of infective complication . Operating masks were shown to have a significant effect on the volume of bacterial organisms falling to the operative site; however, whether this is clinically significant is unknown. J Pharmacol Exp Ther, 2002 Sep, 302(3), 1151 - 7 Fluticasone propionate inhibits lipopolysaccharide-induced proinflammatory response in human cystic fibrosis airway grafts; Escotte S et al.; Airway inflammation, one of the major factors leading to lung damage in cystic fibrosis (CF) patients, is associated with an abnormal increase in proinflammatory cytokines . In this work, we demonstrate the increased release of the proinflammatory cytokines after lipopolysaccharide (LPS) stimulation: human interleukin (hIL)-8 in CF and non-CF airway xenografts, and hIL-6 and human growth-related oncogene-alpha (hGRO-alpha), which could be only analyzed in non-CF xenografts . Under basal conditions, we observed that hIL-8 was higher in CF xenografts compared with non-CF . We also report the anti-inflammatory effect of a glucocorticoid, fluticasone propionate (FP), on CF airway epithelium using a humanized model of airway inflammation developed in nude mice . In CF and non-CF tracheal xenografts, airway inflammation was induced by inoculating Pseudomonas aeruginosa LPS (4 h; 1 microg/ml) in the lumen of the xenografts . FP pretreatment (2 h; 10(-8) M) followed by P . aeruginosa LPS stimulation induced a significant reduction of LPS-induced hIL-8 release in airway liquid collected from CF and non-CF tracheal xenografts (85 and 80%, respectively) . In non-CF tracheal xenografts, FP treatment before LPS stimulation induced a significant decrease in hIL-6 and hGRO-alpha . From these data, we suggest that FP exerts anti-inflammatory properties that may be appropriate to CF therapy, at an early stage of the disease . In addition, these results demonstrate that the humanized airway model of inflammation provides a relevant tool for analyzing the effects of anti-inflammatory drugs in different diseases in which airway inflammation is implicated. Antimicrob Agents Chemother, 2002 Sep, 46(9), 3031 - 4 Prospective survey of beta-lactamases produced by ceftazidime- resistant Pseudomonas aeruginosa isolated in a French hospital in 2000; De Champs C et al.; In 2000, at the Universite d'Auvergne teaching hospital in Clermont-Ferrand, France, 44 (6.2%) strains of Pseudomonas aeruginosa were found to be resistant to ceftazidime . After genotyping, 34 strains were selected . Nine had an additional beta-lactamase: OXA-21 (n = 6), PSE-1 (CARB-2) (n = 2), or PER-1 (n = 1) . Ceftazidime resistance was related solely to the overproduction of the cephalosporinase in 30 strains . Sequencing of five bla(AmpC) genes encoding cephalosporinases with different pIs showed 99% identity with the ampC gene of P . aeruginosa PAO1. Antimicrob Agents Chemother, 2002 Sep, 46(9), 2920 - 5 Consumption of imipenem correlates with beta-lactam resistance in Pseudomonas aeruginosa; Lepper PM et al.; It is generally assumed that the antibiotic prescription policy of a hospital has a significant impact on bacterial resistance rates; however, few studies are available to support this concept with valid statistical data . During a 3-year period from 1997 to 2000, we monitored the consumption of beta-lactam and other antibiotics with known activity against Pseudomonas aeruginosa in a 600-bed community hospital . Monthly isolations of P . aeruginosa were assessed, and resistance rates were recorded . Partial correlation coefficients between consumption and resistance rates were determined, taking into account possible associations with other variables such as seasonal effects and transfers from other hospitals . A total of 30 +/- 7 novel P . aeruginosa strains per month were isolated without epidemic clustering . Prescriptions of imipenem varied significantly during the study period, while prescriptions of other antipseudomonal agents were stable, with the exception of an increase in piperacillin-tazobactam prescriptions . Rates of resistance of P . aeruginosa to the antimicrobial agents used showed a time course similar to figures for imipenem consumption . Monthly rates of resistance to imipenem (partial correlation coefficient {cc}, 0.63), piperacillin-tazobactam (cc, 0.57), and ceftazidime (cc, 0.56) were significantly associated with imipenem prescription rates in the same or the preceding month, while consumption of ceftazidime or piperacillin-tazobactam had no apparent association with resistance . Among the variables investigated, imipenem consumption was identified as the major factor associated with both carbapenem and beta-lactam resistance in endemic P . aeruginosa . Periods of extensive imipenem use were associated with significant increases in resistance . Our data support the concept that a written antibiotic policy which balances the use of various antibiotic classes may help to avoid disturbances of a hospital's microbial sensitivity patterns. Lett Appl Microbiol, 2002, 35(3), 212 - 7 Zinc and glycerol enhance the production of nematicidal compounds in vitro and improve the biocontrol of Meloidogyne javanica in tomato by fluorescent pseudomonads; Siddiqui IA et al.; AIMS: To assess the effects of various carbon and mineral sources on the nematicidal potential of biocontrol inoculants of Pseudomonas aeruginosa IE-6S+ and Ps . fluorescens CHA0 under laboratory and glasshouse conditions . METHODS AND RESULTS: Culture filtrates of strains IE-6S+ and CHA0, cultured in nutrient yeast extract broth, caused substantial mortality of the juveniles of Meloidogyne javanica . The nematicidal activities of the culture filtrates were altered after amendment with various carbon and mineral sources . Soil amendment with zinc alone or in combination with glycerol improved the biocontrol efficacy against root-knot nematode, promoted tomato plant growth and enhanced bacterial rhizosphere and endophytic colonization . CONCLUSIONS: Appropriate quantities of glycerol and zinc alone or in combination enhance the nematicidal activity of Ps . aeruginosa and Ps . fluorescens . Glucose reduces the activity of these bacteria against nematodes . SIGNIFICANCE AND IMPACT OF THE STUDY: Minerals and carbon sources are appealing because they are easy and economical to provide during liquid fermentation of inoculants or as fertilizer amendments to improve the biocontrol activity of indigenous and introduced bacteria. Br J Oral Maxillofac Surg, 2002 Apr, 40(2), 175 - 6 Bilateral eyelid necrosis as a complication of pseudomonal septicaemia; Dickenson AJ et al.; We present a case of bilateral eyelid necrosis as a result of Pseudomonas aeruginosa infection . This is a rare condition that occurs only in neutropenic patients . It may be unilateral or bilateral and requires aggressive management with correction of the neutrophil count, local debridement and systemic antibiotic therapy. DNA Seq, 2002 Feb, 13(1), 67 - 74 Isolation and sequence analysis of the GlnKamtB1amtB2 gene cluster, encoding a PII homologue and two putative ammonium transporters, from Pseudomonas stutzeri A15; Vermeiren H et al.; By PCR, using primers based on heterologous amtB genes, an amtB sequence of Pseudomonas stutzeri A15 was amplified . This DNA fragment was used as a probe in Southern hybridisation experiments and resulted in the isolation and sequence analysis of a 6017 bp genomic fragment of P . stutzeri A15 containing glnKamtB1amtB2 . GlnK codes for a homologue of the nitrogen regulatory PII protein, amtB1 and amtB2 encode putative ammonium transporters . Whereas a glnKamtB gene cluster is common among bacteria, a tandem repeat of ammonium transporter genes has not been reported before . Apart from the presence of a second amtB gene, the gene organisation on this 6 kbp fragment is very similar to a particular region in the genome of Pseudomonas aeruginosa PAO1, relatively closely related to P . stutzeri . Furthermore, the amtB1 gene shows the highest similarity with P . aeruginosa amtB, whereas the amtB2 gene is more closely related to cyanobacterial amtB genes, which are reported to be monocistronically transcribed and not clustered with glnK homologues . Upstream of glnK, NtrC and RpoN recognition sites can be observed . In the intergenic region of glnKamtB1amtB2 no terminators nor extra promoter sequences were observed, indicating that glnKamtB1amtB2 is possibly transcribed as a nitrogen regulated operon. Microbiology, 2002 Aug, 148(Pt 8), 2449 - 56 The ferric uptake regulator of Pseudomonas aeruginosa has no essential cysteine residues and does not contain a structural zinc ion; Lewin AC et al.; The ferric uptake regulator (Fur) of Pseudomonas aeruginosa was expressed in Escherichia coli in its native form and as a fusion to the maltose-binding protein (MBP) . Fur from the MBP fusion bound to MBP after proteolytic cleavage, and the two could only be separated by partial unfolding . The refolded protein was in the same conformation as native protein (as judged by circular dichroism and fluorescence spectroscopies) and was fully active in DNA-binding assays . As-prepared native Fur contained small amounts of Zn(2+) that were easily removed by treatment with EDTA, and apo-protein could be reconstituted with approximately one Zn(2+) ion per monomer . Thus, the P . aeruginosa Fur can probably accommodate a single Zn(2+) ion bound to the metal-sensing site . The single cysteine residue of P . aeruginosa Fur aligns with a cysteine in other members of the Fur family that is essential for activity of the E . coli protein, and is believed to provide one of the ligands to a structural Zn(2+) ion . This cysteine residue was shown to be dispensable for the in vivo activity of P . aeruginosa Fur, which is consistent with the suggestion that the P . aeruginosa protein does not contain a structural Zn(2+) ion . Members of the Fur family contain a highly conserved His-His-Asp-His motif . Alanine substitutions of residues in this motif showed His-87 and His-89 of P . aeruginosa Fur to be essential for activity, whilst His-86 and Asp-88 are partially dispensable. Microbiology, 2002 Aug, 148(Pt 8), 2371 - 81 Characterization of a new efflux pump, MexGHI-OpmD, from Pseudomonas aeruginosa that confers resistance to vanadium; Aendekerk S et al.; Vanadium has an antibacterial activity against Pseudomonas aeruginosa, especially under conditions of iron limitation . Some degree of resistance to V is inducible by prior exposure to the metal . One mutant (VS1) with a higher sensitivity to V was obtained by transposon mutagenesis of P . aeruginosa PA 59.20, a clinical isolate . This mutant had an insertion in a non-coding region, upstream of a cluster of four genes . Three of them show similarities to genes corresponding to known P . aeruginosa antibiotic efflux systems, including an efflux protein, a membrane fusion protein and an outer-membrane porin . This cluster was named mexGHI-opmD . By allelic exchange, three mutants, ncr (for non-coding region), mexI and opmD were constructed in P . aeruginosa PAO1 . Next to V sensitivity, the ncr, mexI and opmD mutants also showed reduced production of elastase, rhamnolipids, pyocyanine, pyoverdine and had reduced swarming motility, phenotypes that are known to be regulated by quorum sensing . All wild-type phenotypes, including growth in the presence of V, were restored by complementation with the complete cluster . The production of N-acyl-homoserine lactones (AHLs) was detected using the Chromobacter violaceum bioassay . Total extracts from the three mutants failed to induce the production of violacein by C . violaceum, although AHLs were detected by TLC and C . violaceum overlay . Violacein production was restored by complementation with mexGHI-opmD . The opmD mutant grew very slowly in LB or CAA medium, indicating that OpmD has an important physiological function for the cell . In conclusion, it is believed that the MexGHI-OpmD pump is probably involved in AHL homeostasis in P . aeruginosa. Saudi Med J, 2002 Jul, 23(7), 802 - 5 Effects of some plant extracts and antibiotics on Pseudomonas aeruginosa isolated from various burn cases; Al-Saimary IE et al.; OBJECTIVE: To determine the major groups of bacteria associated with burn infections, isolation of Pseudomonas aeruginosa from burn cases, and the testing of antibacterial activity of some plant extracts in comparison with the standard antibiotics . METHODS: A total of 92 burn cases, covered with tetracycline (40 cases) and non-covered with tetracycline (52 cases) from both sex and various ages, were collected from various hospitals in Basrah City, Iraq on the year 2001 . Bacteriological investigation for isolation of bacterial pathogens especially Pseudomonas aeruginosa was carried out . Two methods were used to evaluate the anti-bacterial activity of various concentrations of aqueous extracts of leaves of Myrtus communis and Eucalyptus with comparison to 6 antibiotics, these methods were to determine the growth inhibition zones and minimal inhibitory concentration . RESULTS: From a total 92 cases, 78 (84.8%) gave positive cultures . One hundred and fifty eight isolates were identified as bacterial pathogens . Pseudomonas aeruginosa was the predominant bacterial pathogen from 35.9% of the tetracycline covered burns and 42.3% of the non-tetracycline covered burns followed by other bacterial types in various percentages . Aqueous leaves extracts of myrtus communis and eucalyptus gave an excellent effect on bacterial growth and their effects were located within the limits of antibiotic effects . CONCLUSION: Pseudomonas aeruginosa was the predominant bacterial isolate followed by Staphylococcus aureus, then other type of bacterial was isolated in various percentage from each tetracycline covered burns and non-tetracycline covered burns . Most concentrations of the extracts of the studied plants showed a high antibacterial activity against Pseudomonas aeruginosa, and showed significant differences between susceptibility of Pseudomonas aeruginosa isolated from each tetracycline covered burn and non-tetracycline covered burn. Chin Med J (Engl), 2002 Jul, 115(7), 1099 - 100 Inflammatory reaction and alterations of pulmonary surfactant in Pseudomonas Aeruginosa pneumonia in immunocompromised rats; Qu J et al.; Pulmonary surfactant ( PS ) compromises lipids and surfactant proteins (SP) and lines on the alveolar air-liquid interface . It can reduce surface tension, prevent alveoli from collapse and reduce alveoli edema by disaturated dipalmitoylphosphatidylcholine . It also modulates the pulmonary immunology by SP-A and SP-D . In this study,we established a rat model of immunocompromised host (ICH) with pulmonary infection of Pseudomonas aeruginosa (P . aeruginosa), then studied its pulmonary inflammatory reaction and analyzed the concentration of lipids and SP-A in bronchoalveolar lavage fluid (BALF) during infection. Eur J Clin Microbiol Infect Dis, 2002 Jul, 21(7), 553 - 6 Epub 2002 Jul 12. Antiseptic compounds still active against bacterial strains isolated from surgical wound infections despite increasing antibiotic resistance; Giacometti A et al.; The in vitro activities of povidone iodine, potassium peroxymonosulfate, and dimethyldidecylammonium chloride were investigated against 379 nosocomial isolates of Staphylococcus aureus and Pseudomonas aeruginosa responsible for surgical wound infections in patients operated on between July 1995 and June 2001 . Overall, the isolates were inhibited by the antiseptics at concentrations below those used routinely . In spite of increasing resistance to the various antibiotics used to treat surgical wound infections, no significant variation in the susceptibility to antiseptics was demonstrated during this 6-year study. J Trauma, 2002 Aug, 53(2), 284 - 9; discussion 289-90 Granulocyte colony-stimulating factor: release is not impaired after burn wound infection; Gamelli R et al.; BACKGROUND: The production of granulocyte colony-stimulating factor (G-CSF), the lineage specific essential regulator of neutrophil progenitor cell proliferation and differentiation, has been thought to be impaired in the setting of burn infection . The ability to directly measure murine G-CSF allows the further delineation of the G-CSF response in a clinically relevant model of thermal injury and infection . METHODS: We used a commercially available solid phase enzyme-linked immunoabsorbent assay to quantify G-CSF production after burn wound infection in mice . Bone marrow cells, splenic cells, and serum were obtained from BDF1 mice on day 3 after a 15% total body surface area full-thickness scald burn with or without Pseudomonas aeruginosa burn wound infection . G-CSF production of bone marrow cells or splenic cells and the serum level of G-CSF were measured . A clonogenic assay of bone marrow and spleen granulocyte-macrophage progenitor cells as well as blood leukocyte counts were also performed . RESULTS: After burn sepsis, we noted that G-CSF production of the bone marrow and spleen was significantly increased; the numbers of progenitor cells in bone marrow and spleen were markedly enhanced; serum values of G-CSF were 14 times greater than control values; serum colony-stimulating activity was greater than in control mice; and total blood leukocyte counts were significantly depressed . CONCLUSION: These findings support the notion that granulocytopoietic failure after burn sepsis is not significantly related to defective endogenous G-CSF synthesis . More likely, hyporesponsiveness of granulocyte progenitor cells to G-CSF, changes in the relative balance of granulocyte versus monocyte progenitors within the granulocyte-macrophage progenitor cell compartment, and enhanced release of monocyte lineage specific growth factors are the critical elements responsible for burn infection-induced hematopoietic failure. EMBO J, 2002 Aug 15, 21(16), 4207 - 18 Structure of the periplasmic domain of Pseudomonas aeruginosa TolA: evidence for an evolutionary relationship with the TonB transporter protein; Witty M et al.; The crystal structure of the C-terminal domain III of Pseudomonas aeruginosa TolA has been determined at 1.9 A resolution . The fold is similar to that of the corresponding domain of Escherichia coli TolA, despite the limited amino acid sequence identity of the two proteins (20%) . A pattern was discerned that conserves the fold of domain III within the wider TolA family and, moreover, reveals a relationship between TolA domain III and the C-terminal domain of the TonB transporter proteins . We propose that the TolA and TonB C-terminal domains have a common evolutionary origin and are