J Bacteriol, 1992 Feb, 174(4), 1248 - 57 Characterization of In0 of Pseudomonas aeruginosa plasmid pVS1, an ancestor of integrons of multiresistance plasmids and transposons of gram-negative bacteria; Bissonnette L et al.; Many multiresistance plasmids and transposons of gram-negative bacteria carry related DNA elements that appear to have evolved from a common ancestor by site-specific integration of discrete cassettes containing antibiotic resistance genes or sequences of unknown function . The site of integration is flanked by conserved segments coding for an integraselike protein and for sulfonamide resistance, respectively . These segments, together with the antibiotic resistance genes between them, have been termed integrons (H . W . Stokes and R . M . Hall, Mol . Microbiol . 3:1669-1683, 1989) . We report here the characterization of an integron, In0, from Pseudomonas aeruginosa plasmid pVS1, which has an unoccupied integration site and hence may be an ancestor of more complex integrons . Codon usage of the integrase (int) and sulfonamide resistance (sul1) genes carried by this integron suggests a common origin . This contrasts with the codon usage of other antibiotic resistance genes that were presumably integrated later as cassettes during the evolution and spread of these DNA elements . We propose evolutionary schemes for (i) the genesis of the integrons by the site-specific integration of antibiotic resistance genes and (ii) the evolution of the integrons of multiresistance plasmids and transposons, in relation to the evolution of transposons related to Tn21. J Biol Chem, 1992 Jan 15, 267(2), 990 - 6 Characterization of guanosine diphospho-D-mannose dehydrogenase from Pseudomonas aeruginosa . Structural analysis by limited proteolysis; Roychoudhury S et al.; Alginate is believed to be a major virulence factor in the pathogenicity of Pseudomonas aeruginosa in the lungs of patients suffering from cystic fibrosis . Guanosine diphospho-D-mannose dehydrogenase (GDPmannose dehydrogenase, EC 1.1.1.132) is a key enzyme in the alginate biosynthetic pathway which catalyzes the oxidation of guanosine diphospho-D-mannose (GDP-D-mannose) to GDP-D-mannuronic acid . In this paper, we report the structural analysis of GMD by limited proteolysis using three different proteases, trypsin, submaxillary Arg-C protease, and chymotrypsin . Treatment of GMD with these proteases indicated that the amino-terminal part of this enzyme may fold into a structural domain with an apparent molecular mass of 25-26 kDa . Multiple proteolytic cleavage sites existed at the carboxyl-terminal end of this domain, indicating that this segment may represent an exposed region of the protein . Initial proteolysis also generated a carboxyl-terminal fragment with an apparent molecular mass of 16-17 kDa which was further digested into smaller fragments by trypsin and chymotrypsin . The proteolytic cleavage sites were localized by partial amino-terminal sequencing of the peptide fragments . Arg-295 was identified as the initial cleavage site for trypsin and Tyr-278 for chymotrypsin . Catalytic activity of GMD was totally abolished by the initial cleavage . However, binding of the substrate, GDP-D-mannose, increased stability toward proteolysis and inhibited the loss of enzyme activity . GMP and GDP (guanosine 5'-mono- and diphosphates) also blocked the initial cleavage, but NAD and mannose showed no effect . These results suggest that binding of the guanosine moiety at the catalytic site of GMD may induce a conformational change that reduces the accessibility of the cleavage sites to proteases . Binding of {14C}GDP-D-mannose to the amino-terminal domain was not affected by the removal of the carboxyl-terminal 16-kDa fragment . Furthermore, photoaffinity labeling of GMD with {32P}arylazido-beta-alanine-NAD followed by proteolysis demonstrated that the radioactive NAD was covalently linked to the amino-terminal domain . These observations imply that the amino-terminal domain (25-26 kDa) contains both the substrate and cofactor binding sites . However, the carboxyl-terminal fragment (16-17 kDa) may possess amino acid residues essential for catalysis . Thus, proteolysis had little effect on substrate binding, but totally eliminated catalysis . These biochemical data are in complete agreement with amino acid sequence analysis for the existence of substrate and cofactor sites of GMD . A linear peptide map of GMD was constructed for future structure/functional studies. Med J Aust, 1992 Jan 6, 156(1), 20 - 4 Resistance to ciprofloxacin of respiratory pathogens in patients with cystic fibrosis; Dostal RE et al.; OBJECTIVE: To determine the incidence of resistance to ciprofloxacin in respiratory pathogens isolated from patients with cystic fibrosis (CF) compared with that of isolates from patients without CF . The hypothesis was that repeated exposure of these respiratory pathogens to ciprofloxacin would reduce their sensitivity . DESIGN: Isolates of Pseudomonas aeruginosa and Staphylococcus aureus were obtained prospectively from sputa of patients with CF, as part of their routine care . The sensitivities of these isolates to ciprofloxacin were determined by standard agar dilution techniques . SETTING AND PATIENTS: The study was carried out in patients who attended the outpatient clinic or were treated as inpatients of a tertiary referral hospital . Sputa were obtained from 71 patients with CF (age range, 2-31 years) and isolates of P . aeruginosa and S . aureus were compared with those from 54 hospital patients who did not have CF . OUTCOME MEASURES: Sensitivities to ciprofloxacin, expressed as the minimal concentrations required to inhibit growth of the organisms (MIC), were used to make comparisons between different isolates and the same isolates within patients at different times . RESULTS: A higher incidence of ciprofloxacin resistance was displayed by isolates of P . aeruginosa from CF patients who had been previously prescribed ciprofloxacin (MIC50 of 2.0 mg/L and 4.0 mg/L for mucoid and non-mucoid strains respectively) . The MIC of individual organisms tended to rise after a course of ciprofloxacin had been given to their host . A much lower incidence of resistance was displayed by isolates of P . aeruginosa from patients without CF (MIC50, 0.25 mg/L) . Similarly, S . aureus isolates from patients with CF exhibited greater resistance to ciprofloxacin (MIC50, 32 mg/L) than isolates from other patients (MIC50, 0.75 mg/L) . CONCLUSION: The resistance of P . aeruginosa appears to be related to ciprofloxacin exposure, so further development of resistance may be diminished by restricting the frequency of ciprofloxacin administration to individual patients. Cornell Vet, 1992 Jan, 82(1), 69 - 77 Serum concentrations of cefepime (BMY-28142), a broad-spectrum cephalosporin, in dogs; Stampley AR et al.; Serum concentrations of cefepime (BMY-28142) were determined for four dosing regimes, 10 mg/kg or 20 mg/kg, given as single subcutaneous (SC) or intramuscular injections (IM) to dogs . Serial serum samples were analyzed for the presence of cefepime by high-performance liquid chromatography . In experiment 1, the overall mean (+/- SEM) serum concentration (for a 12-hour period) after a dose of 20 mg/kg for SC and IM routes (4.9 +/- 0.74 micrograms/ml and 5.5 +/- 0.63 micrograms/ml, respectively) was twice that for the 10 mg/kg dose given either SC or IM (2.2 +/- 0.31 micrograms/ml and 2.8 +/- 0.47 micrograms/ml, respectively) . There was no significant difference (p greater than 0.05) in mean serum concentrations for SC and IM routes of administration at the same dosage . In subsequent experiments, 5 doses of cefepime (20 mg/kg) were administered IM at 12-hour (experiment 2) or 24-hour (experiment 3) intervals . The mean (+/- SEM) peak serum concentration was 12.1 +/- 1.59 micrograms/ml, 2 hours after the 2nd injection in experiment 2 . In experiment 3, the mean (+/- SEM) peak serum concentration was 10.9 +/- 1.34 micrograms/ml, 4 hours after the 1st injection . Mean trough concentrations in experiment 2 were greater than or equal to 0.5 microgram/ml and less than or equal to 0.5 in experiment 3 . Multiple IM doses produced transient edema at the injection site and mild lameness in all dogs . Cefepime was highly active against single canine isolates of Staphylococcus intermedius, Pseudomonas aeruginosa and Escherichia coli, with minimum inhibitory concentrations of 0.125 microgram/ml, 1 microgram/ml and 0.3 microgram/ml, respectively. Mol Microbiol, 1992 Jan, 6(1), 59 - 66 Pseudomonas aeruginosa AlgB, which modulates the expression of alginate, is a member of the NtrC subclass of prokaryotic regulators; Goldberg JB et al.; The Pseudomonas aeruginosa exopolysaccharide alginate is an important virulence factor in chronic pulmonary infections of cystic fibrosis patients . We determined the nucleotide sequence of the gene, algB, which regulates the level of exopolysaccharide produced by mucoid P . aeruginosa . The predicted amino acid sequence of AlgB revealed a high degree of similarity to the regulatory proteins in the NtrC subclass of 'two-component regulatory systems' . AlgB expression in Escherichia coli minicells showed a molecular weight of approximately 50,000 Da, comparable to that of the inferred amino acid sequence (49,318 Da) . We show that algB is transcriptionally active in mucoid strains of P . aeruginosa and regulates the expression of the alginate biosynthetic gene, algD, thereby resulting in increased expression of alginate in mucoid P . aeruginosa. Cancer Invest, 1992, 10(1), 43 - 59 Pseudomonas aeruginosa infection in cancer patients; Rolston KV et al.; Pseudomonas aeruginosa is an important cause of infection in immunosuppressed patients, particularly those with cancer . However, it is being recognized with greater frequency in patients who appear to be immunocompetent . Changes in modern lifestyles have led to the appearance of some new manifestations of pseudomonas infection including corneal ulceration and keratitis associated with contact lenses, and hot-tub- or whirlpool-associated folliculitis . These represent additional hazards to patients with cancer . Many studies, both in animals and humans, have contributed to our knowledge of the pathogenesis, immunology, treatment, and prevention of pseudomonas infections . Although the aminoglycosides represented a significant step forward in the treatment of these infections, of greater importance was the discovery of the antipseudomonal penicillins . These antibiotics are more effective than the aminoglycosides in neutropenic patients, who are especially susceptible to pseudomonal infections . The older antipseudomonal penicillins (carbenicillin, tircarcillin) have largely been replaced by newer ones (mezlocillin, azlocillin, pipercillin) which are more potent in vitro against P . aeruginosa . Although the accepted therapeutic practice has been to utilize a penicillin in combination with an aminoglycoside, the introduction of newer beta lactam agents and fluoroquinolones with antipseudomonal properties offers the possibility of other approaches to combination therapy . These include the combination of a penicillin or a cephalosporin or the combination of a quinolone with an aminoglycoside or a betalactam antibiotic . However, the development of newer antimicrobial agents is not likely to be a lasting solution to the problem of pseudomonas infections . Since pseudomonas infection often progresses rapidly, optimal results will always depend upon the prompt initiation of appropriate therapy in febrile patients, particularly those who are at high risk . The use of granulocyte transfusions has proved to be of limited benefit . Early data with the use of monoclonal antibodies is promising, and the results of large-scale trials are eagerly awaited . It is hoped that continuing investigation of pseudomonas vaccines will lead to the discovery of effective prophylaxis for highly susceptible patients . It is also hoped that with the availability of GM-CSF it will become possible to reduce the period of risk for serious infections . Finally, a reduction in the frequency of microbiologically proven P . aeruginosa infections in cancer patients should not lead to the assumption that these organisms do not constitute a problem in such patients anymore . The use of prophylactic antibiotics and prompt empiric antibiotic coverage for therapy has resulted in this decline . Cultures are therefore unlikely to be positive with the same frequency as they were before antimicrobial prophylaxis and empiric antibiotic therapy became standard practice.(ABSTRACT TRUNCATED AT 400 WORDS) Plant Mol Biol, 1992 Jan, 18(2), 247 - 58 Arrest of embryo development in Brassica napus mediated by modified Pseudomonas aeruginosa exotoxin A; Koning A et al.; Intracellularly expressed cytotoxins are useful tools both to study the action of plant regulatory sequences in transgenic plants and to modify plant phenotype . We have engineered a low mammalian toxicity derivative of Pseudomonas aeruginosa exotoxin A for intracellular expression in plant cells by fusing the ADP ribosylating domain of the exotoxin gene to plant regulatory sequences . The efficacy of exotoxin A on plant cells was demonstrated by transient expression of the modified exotoxin gene in tobacco protoplasts: the exotoxin gene inhibited the expression of a co-electroporated beta-glucuronidase gene . An exotoxin with an introduced frameshift mutation was also effective at inhibiting beta-glucuronidase expression in the transient assay; the activity of the frameshifted gene was presumably a result of frameshifting during translation or initiation of translation at a codon other than AUG . When fused to napin regulatory sequences, the exotoxin gene specifically arrested embryo development in the seeds of transgenic Brassica napus plants concomitant with the onset of napin expression . The napin/exotoxin chimeric gene did not have the same pattern of expression in tobacco as in B . napus; in addition to exhibiting an inhibition of seed development, the transgenic tobacco plants were male-sterile. J Bacteriol, 1992 Jan, 174(1), 327 - 30 Localization of alg, opr, phn, pho, 4.5S RNA, 6S RNA, tox, trp, and xcp genes, rrn operons, and the chromosomal origin on the physical genome map of Pseudomonas aeruginosa PAO; Romling U et al.; The genes encoding the rrn operons, the 4.5S and 6S RNAs, elements of protein secretion, and outer membrane proteins F and I, and regulatory as well as structural genes for exotoxin A, alkaline phosphatase, and alginate and tryptophan biosynthesis, were assigned on the SpeI/DpnI macrorestriction map of the Pseudomonas aeruginosa PAO chromosome . The zero point of the map was relocated to the chromosomal origin of replication. Chest, 1992 Jan, 101(1), 194 - 8 Recurrent Pseudomonas aeruginosa pneumonia in an intensive care unit; Silver DR et al.; We reviewed the records of all patients in the intensive care unit (ICU) who had Pseudomonas aeruginosa pneumonia over a 2.5-year period . Of patients with P aeruginosa pneumonia, 20 of 34 survived the initial episode of pneumonia . Ten of these 20 developed recurrence . In the nonrecurrent group, nine of ten survived hospitalization, compared to only four of ten in the recurrent group . Comparing the recurrent to the nonrecurrent group, factors associated with recurrence were the APACHE 2 score (12.3 +/- 2.7 vs 8.6 +/- 4.2 {p less than 0.03}), APS score (7.0 +/- 3.5 vs 2.7 +/- 2.1 {p less than 0.01}), and chronic pulmonary disease (8/10 vs 2/10 {p less than 0.05}) . The recurrent P aeruginosa group was younger (63 +/- 10 vs 74 +/- 11 years old {p less than 0.03}) and spent more time receiving mechanical ventilation (95 +/- 64 vs 26 +/- 36 days {p less than 0.01}), in the ICU (101 +/- 61 vs 33 +/- 35 days {p less than 0.01}), and in the hospital (144 +/- 77 vs 84 +/- 32 days {p less than 0.03}) . Although not statistically significant, in the recurrent group, eight of ten patients had tracheostomy and seven of ten had COPD, vs three of ten and two of ten, respectively, in the nonrecurrent group . Recurrent P aeruginosa pneumonia in the ICU is associated with increased morbidity and mortality and does not appear to be related to the adequacy of antibiotic treatment . Chronic lung disease appears to predispose patients to recurrent P aeruginosa pneumonia. Am J Respir Cell Mol Biol, 1992 Jan, 6(1), 116 - 22 Release of mucus glycoconjugates by Pseudomonas aeruginosa rhamnolipid into feline trachea in vivo and human bronchus in vitro; Somerville M et al.; Pseudomonas aeruginosa colonizes the lower respiratory tracts of patients with severe bronchiectasis, including cystic fibrosis, a condition associated with increased airway mucus output . We have shown that an extract containing chloroform-soluble extracellular products of P . aeruginosa releases glycoconjugates into the cat trachea in vivo . This activity was not related to pyocyanin, a major component of the extract, but was associated with the rhamnolipids . Purified monorhamnolipid (100 micrograms/ml) released radiolabeled and periodic acid-Schiff (PAS)-reactive glycoconjugates (delta 3H = +490 +/- 70%, delta 35S = +170 +/- 40%, delta PAS = +8.6 +/- 1.7 micrograms/min; n = 6, P less than 0.02 for each) . Dirhamnolipid (200 micrograms/ml) was also effective (delta 3H = +640 +/- 70%, delta 35S = +130 +/- 20%, delta PAS = +9.3 +/- 1.5 micrograms/min; n = 6, P less than 0.02 for each) . Monorhamnolipid (100 micrograms/ml) also released 35S-labeled and PAS-reactive glycoconjugates from human bronchial tissue in vitro (delta 35S = +189 +/- 47%, delta PAS = +26.3 +/- 8.5 micrograms/min; n = 7, P less than 0.001 versus control tissues in which no stimulus was given) . The cat tracheal glycoconjugates released by the rhamnolipids differed from those released by pilocarpine 50 microM, in having a higher 3H:35S ratio (P less than 0.001) . After gel chromatography on a Sepharose CL-4B column, the void volume fractions of the glycoconjugates also had different profiles in a cesium chloride density gradient . Those released by rhamnolipid banded at 1.62 g/ml, while those released by pilocarpine banded mainly at 1.50 g/ml, with some of the higher density material also present.(ABSTRACT TRUNCATED AT 250 WORDS) Arch Otolaryngol Head Neck Surg, 1992 Jan, 118(1), 94 - 6 Necrotizing 'malignant' external otitis caused by Staphylococcus epidermidis; Barrow HN et al.; Necrotizing "malignant" external otitis is a life-threatening skull base infection that originates in the external auditory canal and is characterized by otalgia and purulent aural discharge with external auditory canal cellulitis and granulation . Necrotizing external otitis, seen almost exclusively in elderly diabetics, is almost always caused by Pseudomonas aeruginosa . To our knowledge, there have been only six nonpseudomonal cases reported to date . We describe a 70-year-old diabetic man with necrotizing external otitis caused by Staphylococcus epidermidis, confirmed by serial cultures . This case was characterized by otalgia, purulent otorrhea, preauricular swelling, bony external auditory canal erosion, and a conductive hearing loss . Despite prolonged intravenous antistaphylococcal antibiotic therapy and frequent local debridement, the patient's symptoms never completely resolved . As demonstrated by the treatment failure, S epidermidis necrotizing external otitis, may represent a more refractory form of this already virulent disease process . We believe this to be the first reported case of necrotizing external malignant otitis caused by S epidermidis. J Infect Dis, 1992 Jan, 165(1), 26 - 33 Human monoclonal antibodies to glycolipid A that exhibit complement species-specific effector functions; Winkelhake JL et al.; Two human IgM monoclonal anti-glycolipid A antibodies (MAbs) were evaluated for their abilities to bind to various endotoxins and pathogenic gram-negative bacteria and to activate complement pathways, thereby accomplishing bactericidal and opsonic effector functions . Both MAbs cross-reacted with glycolipid A mutant lipopolysaccharides from rough colony-forming gram-negative bacteria and with selected endotoxins from smooth colony-forming bacteria . However, MAb 10235 bound to all clinical isolates of Escherichia coli and Klebsiella pneumoniae tested but only very weakly to Pseudomonas aeruginosa, whereas MAb 10058 bound to all three genera . Several strains of serum-insensitive organisms were selected for evaluation of antigen-specific, complement-mediated effector functions for the two MAbs . Assessment of bactericidal and opsonic activities showed that neither MAb was able to activate complement from nonprimate species (mouse, rat, rabbit, guinea pig, or sheep) . However, both MAbs were highly effective in using primate sources of serum complement to mediate these effector functions. Intensive Care Med, 1992, 18 Suppl 1, S35 - 8 Immunological perspectives in prevention and treatment of nosocomial pneumonia; Pennington JE; The high mortality associated with current therapeutic approaches to nosocomial pneumonia has motivated consideration of newer immunologic approaches to prevention or therapy of this infection . Serotype specific vaccines, hyperimmune immunoglobulins, and monoclonal antibodies have been developed for certain problematic pathogens . Pseudomonas aeruginosa has been the major focus of this approach, and trials of hyperimmune anti-Ps . aeruginosa globulins for treatment of pneumonia are underway . Broad-spectrum, anti-lipopolysaccharide antibody preparations have also been employed for prophylaxis of nosocomial pneumonia, but to date these trials have not been successful . Finally, anticytokine antibody therapy to reduce infection-initiated inflammatory lung damage is under consideration. Proc Natl Sci Counc Repub China B, 1992 Jan, 16(1), 10 - 6 Removal of copper ion by Pseudomonas spp; Chao WL; Copper-resistant Pseudomonas sp . 41Y, Pseudomonas pseudomallei 13-1 and Pseudomonas aeruginosa 7 were used in the present study . When the latter two organisms were added to copper-containing 1/3 strength Tryptic Soy Broth, more than 99.5% of the copper ion was removed from the medium within 24 h . If copper solution was added to hog waste slurry, a reduction in the copper ion concentration could be detected only when the added bacteria started to grow in it, whereas in a mineral medium supplemented with glycerol-2-phosphate, both bacteria could remove about 50% of the copper ion from the medium within 24 h . When cell suspension of Pseudomonas sp . 41Y was autoclaved, no copper ion removal was observed . Different incubation temperatures, including 30 degrees C, 37 degrees C and 45 degrees C, had no effect on the percent of copper ion removed by both Pseudomonas sp . 41Y and P . pseudomallei 13-1 . On the other hand, if the pH value of the solution was lowered from 8.2 to 6.0, there was a drastic decrease in copper removal . A similar reduction of copper ion removal ability was also observed with the addition of lead ion . When cells of Pseudomonas sp . 41Y were embedded in sodium alginate, there was a decrease in its ability to remove copper ion as compared to the free-living cells. J Hyg Epidemiol Microbiol Immunol, 1992, 36(1), 105 - 10 Biological carrier improves passive protection of mice against Pseudomonas aeruginosa infection; Sourek J et al.; In a model experiment, the use of specific hyperimmune globulins (SHG) alone failed to protect mice against infection with homologous and heterologous P . aeruginosa serotypes . However, the therapeutic potential of SHG dramatically improved after its conjugation with A1(OH)3, used as a biological carrier . The binding of SHG to this carrier proved to be the most effective and stable combination in the treatment of acute pseudomonad infections in mice. Chemotherapy, 1992, 38(1), 21 - 7 Bactericidal activities of ofloxacin and its optically active isomer (DR-3355) on non-growing cells of Escherichia coli and Pseudomonas aeruginosa; Tanaka M et al.; In this paper the bactericidal activities of ofloxacin and its optically active derivative, DR-3355, against non-growing cells of Escherichia coli and Pseudomonas aeruginosa are described . E . coli and P . aeruginosa were killed rapidly by ofloxacin and DR-3355 . After treatment with these quinolones, the resting cells of E . coli and P . aeruginosa became plasmolyzed, with apparent cytoplasmic shrinkage without filamentation . Membrane-bound intracellular vacuoles and disruption of the cell envelope were also observed, resulting in extrusion of the cytoplasmic contents . These results indicate that non-growing cells of E . coli and P . aeruginosa were susceptible to ofloxacin and DR-3355, as were logarithmically growing cells. Ophthalmic Res, 1992, 24(1), 32 - 9 Distribution and kinetics of the inflammatory cell response to ocular challenge with Pseudomonas aeruginosa in susceptible versus resistant mice; Hazlett LD et al.; This study examined and characterized the distribution and kinetics of the inflammatory cell response to pseudomonas ocular challenge in susceptible C57BL/6J and resistant DBA/2J mice . Initially, in the cornea, the number of neutrophilic leukocytes (PMNs), macrophages/monocytes or lymphocytes was 2-2.5 times greater in resistant versus susceptible mice . The peak cellular response in the cornea was also greater in resistant than in susceptible animals . Further, resistant mice, when compared with susceptible mice, had a shorter duration of inflammatory cells as well as bacteria in the cornea . These data were similar for the cell infiltrate in the anterior chamber, with the exception that PMNs were initially greater in number in C57BL/6J than in DBA/2J mice . Collectively these data suggest that susceptible mice are, in general, cellularly hyporesponsive to pseudomonas ocular challenge when compared with resistant animals . This, together with persistence of inflammatory cells and bacteria in the cornea of susceptible animals, may contribute to their failure to restore corneal clarity following pseudomonas ocular challenge. Chemotherapy, 1992, 38(2), 82 - 91 Lipopolysaccharide alterations responsible for combined quinolone and beta-lactam resistance in Pseudomonas aeruginosa; Leying HJ et al.; Resistant variants of three clinical Pseudomonas aeruginosa isolates were obtained in the presence of aztreonam . The variants exhibited a four- to eightfold increase in the minimal inhibitory concentrations to beta-lactam antibiotics (except imipenem) to quinolones, such as norfloxacin and fleroxacin, chloramphenicol and tetracycline, but not to gentamicin and polymyxin B . beta-Lactamase production was barely detectable in both wild-type strains and the resistant clones . Only ampicillin, cefoxitin and imipenem increased the production of beta-lactamase, whereas various other beta-lactams did not . Penicillin-binding proteins remained unchanged in the aztreonam-resistant clones . The analysis of the outer membrane proteins did not reveal differences in the outer membrane proteins between the wild-type strains and the aztreonam-resistant clones . Two of the three antibiotic-resistant isogenic clones contained less lipopolysaccharides (LPSs) than their corresponding wild-type strains . Moreover, it could be demonstrated that the ratio of 2-keto-3-deoxy octonate to carbohydrate of the LPS changed in any case between the wild-type strains and the aztreonam-resistant clones . These alterations were accompanied by a decrease in surface hydrophobicity of the resistant clones as compared to the wild-type strains . Therefore, quantitative as well as qualitative alterations in the LPS may provide an explanation for the resistant phenotype observed. Antimicrob Agents Chemother, 1992 Jan, 36(1), 71 - 6 High-level beta-lactamase activity in sputum samples from cystic fibrosis patients during antipseudomonal treatment; Giwercman B et al.; The in vivo activity and source of beta-lactamase in sputum samples from 43 patients with cystic fibrosis (CF) during a 2-week antipseudomonal treatment were studied . A colorimetric method, based on the conversion of nitrocefin, was used for quantitation of the sputum beta-lactamase activity . beta-Lactamases in sputum were characterized by isoelectric focusing and inhibition profile and were compared with the beta-lactamases extracted from Pseudomonas aeruginosa isolated from the paired sputum samples . We found that the beta-lactamase activity increased to high levels in sputum from patients with CF during the course of piperacillin, ceftazidime, cefsulodin, or imipenem therapy . Aztreonam therapy lead to opposite results because the beta-lactamase activity decreased and aztreonam was able to mask beta-lactamase activity by acting as an inhibitor . All sputum beta-lactamases displayed characteristics indicative of a class I enzyme, identical to the beta-lactamases extracted from P . aeruginosa . The presence of beta-lactamase at such levels could lead to in vivo inactivation of beta-lactam antibiotics . This study supports the hypothesis that beta-lactamase production is an important in vivo resistance mechanism in P . aeruginosa-infected patients with CF. Minerva Anestesiol, 1992 Jan-Feb, 58(1-2), 1 - 5 {Evaluation of bacterial resistance to pefloxacine after prolonged use in resuscitation}; Malacarne P et al.; In an overall of the value of an antibiotic it is important to take into account the onset of bacterial resistance in addition to its immediate clinical effects since the former can render an otherwise efficacious antibiotic obsolete within a short space of time . We studied two groups of intubated patients with pneumonia infections during two different periods in 1990: January-June and October-December; each patient was treated with pefloxacin 400 mg twice a day i.v . for 6 days on the basis of an antibiogram carried out on tracheobronchial secretion; at the end of that period patients were clinically evaluated and a second bacteriological test was performed . It was found that the percentage of pefloxacin-resistant bacterial strains did not increase significantly after this antibiotic had been used for a year for pneumonia infections (from 27.5% to 33%) . The appearance of bacterial resistance at the six-day treatment cycle was similar in both groups (19% and 22%) . Of all the bacterial strains, Pseudomonas aeruginosa showed the greatest tendency to become resistant. Arzneimittelforschung, 1992 Jan, 42(1), 70 - 2 Synthesis and antipseudomonal activities of some ofloxacin esters as prodrugs; Ertan M et al.; Three new ofloxacin esters have been synthesized as prodrug by the reaction of ofloxacin (CAS 82419-36-1) with chloromethylacetate, 1-chloroethylacetate and 1-chloroethylethylcarbonate in acetonitrile . The structures of the compounds have been elucidated by UV, IR, 1H-NMR, Mass spectra and elementary analysis . In vitro activities of these compounds against clinical isolates of various Pseudomonas aeruginosa species have been determined by microtiter tube dilution method, and octanol/water partition coefficients and pH dependent hydrolysis rates have been investigated in comparison with ofloxacin. Eur Surg Res, 1992, 24(2), 69 - 76 Effect of polymyxin B on intestinal bacterial translocation in Pseudomonas aeruginosa wound-colonized burned mice; Dijkstra HM et al.; Bacterial translocation (BT) from the gastrointestinal tract has been proposed to play a role in the pathogenesis of septic complications in severely burned patients . In a burn model the effect of a subtherapeutic dose of polymyxin B-sulfate (PB) at BT was examined in Escherichia coli-monoassociated mice with Pseudomonas aeruginosa-inoculated burn wounds . The BT incidence and number of translocating microorganisms to the spleen (p less than 0.01), liver (p less than 0.01), lung (p less than 0.05) and heart (p less than 0.05) were diminished significantly in the PB-treated versus the untreated group . Endotoxin in plasma was detectable in one of the 16 PB-treated versus 6 of the 17 control mice (p less than 0.05) . The relation of Pseudomonas burn wound inoculation, BT, endotoxin and the endotoxin-neutralizing properties of PB will be discussed. Diagn Microbiol Infect Dis, 1992 Jan, 15(1), 73 - 80 New insights into the activity of third-generation cephalosporins against pneumonia-causing bacteria; Jones RN et al.; Over 300 isolates representing all pathogens causing greater than or equal to 4% of nosocomial or outpatient pneumonias were tested against currently used third-generation cephalosporins (cefotaxime, desacetylcefotaxime, ceftriaxone, ceftazidime, cefoperazone, and ceftizoxime) to determine differences in activity and effects of physiologic host and pharmacokinetic properties . Prevalent drug resistances were represented and tests were performed by reference methods of the National Committee for Clinical Laboratory Standards . Spectrums and potency of cefotaxime, desacetylcefotaxime, ceftriaxone, and ceftizoxime were most similar, but cefotaxime plus desacetylcefotaxime at in vivo ratios increased the cefotaxime spectrum (anaerobes and Pseudomonas) and potency . Ceftizoxime was least active because of current reduced activity against some Staphylococcus spp . and Pseudomonas aeruginosa . Ceftriaxone potency was adversely affected (greater than or equal to 4-fold decrease) by serum protein binding, thus reducing its susceptibility spectrum for pathogens with greater than or equal to 4 micrograms/ml minimum inhibitory concentrations (MICs) and a 10.6% reduced spectrum overall . Ceftazidime provided poorest coverage against the significant and clinically increasing Gram-positive cocci and did not significantly inhibit aspiration pneumonia causing anaerobic strains . Ceftazidime and cefoperazone were more active against pseudomonas, but they were most labile to newer extended-spectrum beta-lactamases . On empiric balance, the third-generation cephalosporins continue to provide the best therapeutic spectrum, particularly those favorably influenced by host factors (proteins and metabolism) . These third-generation cephalosporin differences become more important since some agents (ceftazidime) have readily selected type-I enzyme mutants among intensive-care-unit respiratory tract pathogens at our institution . Cost containment will also influence drug choices for some third-generation cephalosporins, usually favoring the earliest introduced compounds such as cefotaxime. Mikrobiyol Bul, 1992 Jan, 26(1), 17 - 25 {Pyocin typing of Pseudomonas aeruginosa strains isolated from various sources}; Kantarci G; In our study, 103 strains of P.aeruginosa from various clinical specimens were typed by pyocin typing method with 13 indicator strains . As a result of pyocin typing, 18 different pyocin type were detected from 81 typable strains (78.6%), 22 of P.aeruginosa strains (21.3%) could not be typed because of the lack of their pyocin activity . On the other hand, 2 of typable P.aeruginosa strains were found to produce inhibition patterns that differed from standard inhibition patterns according to Govan and Gillies Method . Because of this reason, these two strains could not be classified . As a result of our study, it was observed that, strains that belong to pyocin type-1 were in majority . It was detected that, TSA Medium supplemented with 5% sheep blood can be used easily instead of TSA Medium, supplemented with 5% horse blood. Exp Lung Res, 1992 Jan-Mar, 18(1), 155 - 71 Acute lung injury induced by Pseudomonas aeruginosa elastase in hamsters; Williams JC et al.; Human neutrophil elastase (HNE) is the predominant elastolytic enzyme in the sputum of cystic fibrosis (CF) patients . However, a variably small portion of the activity can be ascribed to Pseudomonas aeruginosa elastase (PaE) . The purpose of these studies was to evaluate the activities of the two elastases in an in vivo model of acute lung injury (ALI) . The elastolytic activity of Pseudomonas aeruginosa elastase (MW = 39K) and human neutrophil elastase (MW = 33K) were also examined using insoluble bovine neck and lung elastin . The ability of hamster serum to inhibit elastinolysis by the two elastases was also examined . On a per milligram protein basis, PaE was the more potent elastase, regardless of substrate, and it preferentially hydrolyzed lung relative to neck elastin . PaE is poorly inhibited by hamster serum compared to HNE . In vivo, PaE is much more efficient than HNE in inducing an acute lung injury in hamsters . The duration of effects induced by doses of the two proteases that produce similar acute biological effects are essentially identical . The increases of lung weight and total lavagable WBCs persist for at least 7 days . All other parameters return to baseline between 3 and 5 days . The predominant cells in the lavage 1 and 2 days post insult are PMNs . By day 7, the predominant cell is the macrophage . These data suggest that even though PaE is a minor component of the elastolytic activity in CF patients, it may still contribute significantly to the pathology of the disease. Clin Infect Dis, 1992 Jan, 14(1), 353 - 4 Treatment of endocarditis due to Pseudomonas aeruginosa with imipenem; Fichtenbaum CJ et al.; Therapy for endocarditis due to Pseudomonas aeruginosa is complicated by the emergence of resistance during therapy, lack of universally available synergistic antimicrobial agents, and unacceptably high morbidity and mortality rates . The authors report a case of aortic valve endocarditis due to P . aeruginosa in which resistance to piperacillin developed during combined therapy with tobramycin . Bacteriologic cure was obtained with a combination of imipenem/cilastatin and tobramycin . The authors review six other cases of P . aeruginosa endovascular infections treated with imipenem. Cornea, 1992 Jan, 11(1), 47 - 52 Attachment of Pseudomonas to human-worn, disposable etafilcon A contact lenses; Boles SF et al.; After 7 days of continuous wear, Acuvue (Vistakon, Jacksonville, FL, U.S.A.; etafilcon A) lenses were soaked in a Pseudomonas aeruginosa suspension (1.4 x 10(8) cfu/ml) . New Acuvue lenses served as controls . A single strain of P aeruginosa harvested from a human corneal ulcer was used throughout the experiment . Lenses were examined by culture and scanning electron microscopy (SEM) . We found significantly greater (p less than 0.05) bacterial attachment to new Acuvue lenses {culture, 3.1 x 10(4) (+/- 0.82 x 10(4)) cfu/mm2; SEM, 2.6 x 10(4) (+/- 0.47 x 10(4)) bacteria/mm2} compared with those previously worn {culture, 1.0 x 10(4) (+/- 0.17 x 10(4)) cfu/mm2; SEM, 0.73 x 10(4) (+/- 0.21 x 10(4)) bacteria/mm2} . No statistical difference was found among the individuals . Our findings demonstrate that the biological coating resulting from 1 week of continuous contact lens wear restricts P . aeruginosa attachment to the Acuvue lens when comparing new and used lenses. Microbiologica, 1992 Jan, 15(1), 65 - 9 beta-Lactamase Id of ceftazidime-resistant Pseudomonas aeruginosa strains; Michel-Briand Y et al.; 4.2% Pseudomonas aeruginosa strains isolated in our hospital were resistant to ceftazidime . The 174K strain was also resistant to azthreonam but susceptible to imipenem and was studied as representative of these strains . It produced a single beta-lactamase (pI 8.6) which had all the characteristics of the chromosomal beta-lactamase Id and was the only beta-lactamase present . This enzyme hydrolyses slowly ceftazidime and imipenem . It could be a factor of imipenem resistance if the antibiotic influx into the bacteria was decreased or if the beta-lactamase Id was synthesized at a high level. Refract Corneal Surg, 1992 Jan-Feb, 8(1), 39 - 43 Keratotomy model of pseudomonas keratitis: gentamicin chemotherapy; Brockman EB et al.; BACKGROUND: Chemotherapy of bacterial keratitis requires frequent application of antibiotic drops . Collagen shields containing antibiotics could reduce the need for frequent antibiotic application . To determine the effect of gentamicin-containing collagen shields and gentamicin drops on Pseudomonas keratitis, a new keratotomy model of infection was employed . METHODS: Model--contact lenses (58% water content) presoaked in 1% bovine serum albumin and exposed to 10(8) colony forming units per mL of Pseudomonas aeruginosa strain 27853, were found to reproducibly retain 5.9 (log base 10) colony-forming units . Rabbit corneas were scarified centrally with two perpendicular intersecting diamond knife cuts (5 mm x 5 mm x 0.2 mm), and bacteria-impregnated contact lenses were positioned and held in place for 24 hours with partial tarsorrhaphies . Treatment--Fourteen hours after lens removal (38 hours after infection), corneas were treated for 8 hours with collagen shields hydrated in saline (control), or shields impregnated with 800 micrograms gentamicin during manufacture, or one drop every 30 minutes of fortified gentamicin drops (14 mg/mL) . The rabbits were killed and corneas collected for bacterial enumeration after 8 hours of treatment (46 hours after infection) . RESULTS: Model--Slit-lamp examination and microbiologic confirmation showed uniformity of keratitis in all eyes . Treatment--Corneas treated with saline (controls) contained 6.4 (log base 10) Pseudomonas . Corneas treated with gentamicin-impregnated collagen shields (total drug = 800 micrograms) and fortified gentamicin drops (total drug = 21 mg) showed a reduction in viable bacteria of 2 logs and 6 logs, respectively, relative to the control . CONCLUSIONS: In this new model of Pseudomonas keratitis, the amount of gentamicin introduced into collagen shields during manufacture effectively reduced bacterial growth in infected rabbit corneas . However, larger amounts of drug applied as fortified drops on a frequent dosing schedule were more effective by a factor of three . Treatment of keratitis with antibiotic-impregnated collagen shields may reduce the need for very frequent application of topical drops, but may be more effective with topical drop supplementation to increase the amount of drug available over the course of therapy. J Antibiot (Tokyo), 1992 Jan, 45(1), 103 - 12 Synthesis and structure-activity relationships of a new series of cephalosporins, E1040 and related compounds; Sugiyama I et al.; The synthesis and in vitro antibacterial activity of a series of 7-{(Z)-2-aminoaryl-2-oxyiminoacetamido}-3-ammoniomethyl++ +-3-cephems are described . Variation of an oxyimino moiety with aminoaryl at the C-7 side chain and a quaternary ammonium moiety at the C-3 side chain were examined and structure-activity relationships were studied . E1040, the 3-(4-carbamoylquinuclidinio)methyl derivative of the 7-alpha-methoxyimino series of aminothiadiazolyl cephalosporins, exhibited excellent activity against both Gram-positive and Gram-negative bacteria, particularly against Pseudomonas aeruginosa, and possessed high stability to beta-lactamases. J Laryngol Otol, 1992 Jan, 106(1), 5 - 6 Malignant external otitis: management policy; el-Silimy O et al.; Malignant external otitis is a progressive pseudomonal infection of the external auditory canal and adjacent structures . In the literature there is no unified policy regarding the management of malignant external otitis . The development of an effective nuclear scanning method and antibiotics active against Pseudomonas aeruginosa have helped in formulating our management policy . A review of four years personal experience with this condition is presented . All of our cases were cured from the disease with no fatality . Gallium citrate scans showed that antipseudomonal treatment should continue for up to three months. J Heart Lung Transplant, 1992 Jan-Feb, 11(1 Pt 1), 160 - 3 Pseudoaneurysm of the aorta after heart-lung transplantation: diagnosis by color flow Doppler mapping; Balaji S et al.; Five months after heart-lung transplantation for treatment of end-stage cystic fibrosis, a 14-year-old girl had a swelling over the manubrium that was identified as a pseudoaneurysm at the aortic anastomotic site by means of cross-sectional echocardiography with color flow Doppler mapping . The diagnosis was confirmed at operation, despite which she died . Biopsy material taken during the operation revealed chronic sternal osteomyelitis caused by Pseudomonas aeruginosa . Disruption of the aortic anastomosis by infection may be a major complication of heart-lung transplantation for treatment of cystic fibrosis. Appl Environ Microbiol, 1992 Jan, 58(1), 174 - 80 Production, purification, and properties of a lipase from a bacterium (Pseudomonas aeruginosa YS-7) capable of growing in water-restricted environments; Shabtai Y et al.; An extracellular lipase from the low-water-tolerant bacterium P . aeruginosa YS-7 was produced, purified, and characterized with respect to its functional properties in aqueous solutions and organic solvents . The enzyme was partially released from the cells during fermentation in defined medium with 5% (wt/vol) soybean oil . Approximately one-half of the total culture activity remained in solution after removal of cells . More than 95% of the activity was found in culture supernatant after mild detergent treatment (10 mM sodium deoxycholate) or after shifting the carbon source during the fermentation from triglyceride to a free fatty acid . The enzyme was recovered from an acetone precipitate of the whole culture and purified by hydrophobic interaction chromatography, yielding a preparation having a specific activity of about 1,300 mumol of fatty acid mg-1 h-1 . The lipase (molecular size, approximately 40 kDa) hydrolyzes a variety of fatty acid esters and has an optimum pH of about 7 . The enzyme retained its full activity at 20 to 55 degrees C, even after prolonged exposure (more than 30 days) to different concentrations of water-miscible organic solvents such as alcohols, glycols, pyridine, acetonitrile, dimethyl formamide, and dimethyl sulfoxide . The hydrolysis of 4-nitrophenyl laurate ester and of triglyceride emulsified in water was slightly accelerated with increasing concentrations of alcohols and glycols up to about 20% but was abolished with a further increase in alcohol concentration or in the presence of acetonitrile . In contrast, the rate of hydrolysis of these substrates in concentrated solutions of dimethyl formamide or dimethyl sulfoxide was markedly increased, by more than twofold and more than fivefold, respectively.(ABSTRACT TRUNCATED AT 250 WORDS) Thorax, 1992 Jan, 47(1), 6 - 13 Role of alginate in infection with mucoid Pseudomonas aeruginosa in cystic fibrosis; Pedersen SS et al.; BACKGROUND: Chronic bronchopulmonary infection with mucoid, alginate producing Pseudomonas aeruginosa occurs characteristically in patients with cystic fibrosis . Alginate may be a virulence factor for P aeruginosa infection in such patients . METHODS: Forced vital capacity (FVC), nutritional state and the antibody response to P aeruginosa were determined at regular intervals from three years before chronic P aeruginosa infection to 10 years afterwards in 73 patients with cystic fibrosis . All patients were treated intensively with antipseudomonal chemotherapy during the study period . RESULTS: FVC was reduced in all patients who subsequently developed P aeruginosa infection before they acquired the infection, indicating significant pre-existing lung damage when compared with patients who remained free of P aeruginosa . Lung function and nutritional state remained unchanged after 10 years of infection, except in the patients who died of P aeruginosa lung infection . The FVC and height and weight of patients infected with nonmucoid strains of P aeruginosa were similar to those of uninfected patients . Patients infected with mucoid strains had poorer lung function and nutritional state for the first five years after infection compared with patients with nonmucoid strains . Such infection was also associated with greater IgG and IgA antibody responses to P aeruginosa standard antigen compared with nonmucoid infection . Concentrations of antibody to alginate were similar in patients with non-mucoid and mucoid infection . Noticeably increased concentrations of IgA antibodies to P aeruginosa standard antigen were observed early after the onset of infection in patients who subsequently died . CONCLUSION: Alginate producing P aeruginosa infection is associated with a hyperimmune response and poor clinical condition, suggesting that alginate production is a virulence factor in such infections in patients with cystic fibrosis. APMIS, 1992 Jan, 100(1), 87 - 90 Local IgA and IgG response to intratracheal immunization with Pseudomonas aeruginosa antigens; Johansen HK et al.; We have experimentally immunized rats intratracheally with sonicated Pseudomonas aeruginosa to develop a high antibody response systemically and locally . The systemic antibodies were measured by a standard enzyme-linked immunosorbent assay (ELISA) on serum samples, whereas the local antibodies were measured on eluates from paper discs containing saliva . High levels of IgA antibodies were elicited in saliva whereas only traces of IgG antibodies were detected; the opposite results were found in serum . The saliva disc method permits serial measurements from the same animal and therefore offers the possibility to follow post-immunization antibody responses. Photochem Photobiol, 1992 Jan, 55(1), 89 - 96 Inactivation of gram-negative bacteria by photosensitized porphyrins; Nitzan Y et al.; Photosensitization of Escherichia coli and Pseudomonas aeruginosa cells by deuteroporphyrin (DP) is shown to be possible in the presence of the polycationic agent polymyxin nonapeptide (PMNP) . Previous studies established complete resistance of Gram-negative bacteria to the photodynamic effects of porphyrins . The present results show that combined treatment of E . coli or P . aeruginosa cultures with DP and PMNP inhibit cell growth and viability . No antibacterial activity of PMNP alone could be demonstrated and cell viability remained unchanged . Spectroscopically, PMNP was found to bind DP, a mechanism which probably assists its penetration into the cell's membranes . Insertion of DP into the cells was monitored by the characteristic fluorescence band of bound DP at 622 nm . Binding times were 5-40 min and the extent of binding increased with decreasing the pH from 8.5 to 6.5 . DP binding constants, as well as the concentrations of PMNP which were required for maximal effect on the various Gram-negative bacteria, were determined fluorometrically . By the treatment of DP, PMNP and light the growth of E . coli and P . aeruginosa cultures was stopped and the viability of the culture was dramatically reduced . Within 60 min of treatment the survival fraction of E . coli culture was 9 x 10(-6) and that of P . aeruginosa was 5.2 x 10(-4) . Electron microscopy depicted ultrastructural alterations in the Gram-negative cells treated by DP and PMNP . The completion of cell division was inhibited and the chromosomal domain was altered markedly. Microbios, 1992, 70(283), 77 - 91 Bacterial uptake of 14C-chlorhexidine diacetate and 14C-benzyl alcohol and the influence of phenoxyethanol and azolectin: studies with gram-negative bacteria; Fitzgerald KA et al.; The uptake of 14C-chlorhexidine (14C-CHA) by Pseudomonas aeruginosa and smooth, rough and deep rough strains of Escherichia coli was very rapid with maximum uptake occurring within 20 s . Despite the rapid binding, the lethal action of CHA, although concentration-dependent, is comparatively slow and occurs in minutes rather than seconds . This indicates that the initial rapid binding is followed by a second slower action, responsible for the lethal effects of CHA . The lethal action could be accelerated, particularly at modest concentrations of CHA, by the simultaneous presence of phenoxyethanol (POE) or benzyl alcohol (BZA), although the magnitude of the effect was small . Both alcohols had little effect on the binding of 14C-CHA, which does not explain the enhanced bactericidal action of CHA . Uptake of 14C-benzyl alcohol (14C-BZA) by the same strains showed very different patterns with slower and time-related binding . CHA had a marked effect on BZA absorption but no direct link was established between binding patterns and cell death . The CHA neutraliser, azolectin, removed bound CHA (in the presence or absence of POE) very efficiently even at contact times of only 20 s. Arch Toxicol, 1992, 66(3), 224 - 7 Cytotoxicity of mebendazole against established cell lines from the human, rat, and mouse liver; Higa F et al.; The direct cytotoxicity of mebendazole (MBZ) was investigated by using cell lines derived from human, mouse and rat liver . It was demonstrated that Chang liver cells (derived from human liver) were more sensitive to the cytotoxic effects of MBZ than the other two cell lines . Longer incubation of the cells with MBZ resulted in stronger toxicity, and the cytotoxicity was dependent on the MBZ concentration above a certain threshold value (0.25-0.50 mg/l in a 42-h culture) . Inhibition of the proliferation of Chang liver cells by MBZ was detected at a concentration of 0.008 mg/l, a lower concentration than that having a cytotoxic effect . The other two cell lines were less sensitive to the inhibitory effect of MBZ . Proliferation of human mononuclear cells following stimulation by phytohemagglutinin (PHA) was inhibited by MBZ, and this inhibition was more extensive than that of cells stimulated with whole formalin-treated Pseudomonas aeruginosa . It is suggested that dividing cells may be more sensitive to MBZ cytotoxicity . This anti-proliferative effect may be related to its clinically known side effects, such as hepatotoxicity and bone marrow suppression. Folia Microbiol (Praha), 1992, 37(5), 360 - 4 Permeability factor, cytotoxicity and serotyping of Pseudomonas aeruginosa strains; Hostacka A et al.; We analyzed in detail the permeability and cytotoxic activity as well as the serotypes of 127 Pseudomonas aeruginosa strains . Sixty-seven strains were isolated from immunocompromised patients (51 from patients with tumors and 16 from patients after transplantation) and 60 strains were isolated from patient's ears . Culture filtrates of strains isolated from patients after transplantation were responsible for the highest part of permeability reactions corresponding to an intermediate toxin production (68.8%) (categories 2 and 3) and culture filtrates of strains isolated from patients with tumors caused the highest percentage of permeability reactions corresponding to a strong toxin production . Culture filtrates of strains isolated from ears of patients were responsible for the highest percentage of negative permeability reactions (15%) . With positive permeability reaction size (categories 2-6) increased also the percentage of cytotoxicity as well as the intensity of morphological changes on Vero cells after 1 and 2 d . We did not observe any relationship between a particular permeability reaction category and the most frequent serotypes (O4, O6) or nontypable strains of the tested groups. Microbiol Immunol, 1992, 36(11), 1195 - 200 The patterns and transmissibility of antibiotic resistance among clinical strains of Pseudomonas aeruginosa; Palillo ES et al.; Four hundred and ninety-eight predominantly pyocin-type 10 clinical strains of Pseudomonas aeruginosa were analyzed for resistance to carbenicillin, cefoperazone, cefotaxime, ceftazidime, gentamicin, amikacin and netilmicin . Based on NCCLS-recommended MIC breakpoints, 245 strains were found to be resistant, of which 41.6% were resistant to carbenicillin, 38% to gentamicin, 37.8% to netilmicin, 26.3% to cefoperazone, 17.9% to cefotaxime, 0.6% to amikacin and none to ceftazidime . Quadruple resistance to carbenicillin, cefoperazone, gentamicin and netilmicin was the most frequent pattern observed . Resistance to older antibiotics (kanamycin, streptomycin and tetracycline) and to mercuric chloride were also common . Conjugation experiments suggested that self-transmissible and non-transmissible plasmids occurred in at least 66 strains. Microbiol Immunol, 1992, 36(11), 1113 - 8 Co-existence of colonies with different serotypes and other biological characteristics in clinical isolates of Pseudomonas aeruginosa; Kobayashi I et al.; The biological characteristics of individual colonies of Pseudomonas aeruginosa from 138 specimens were investigated . Of these isolates, 90 (65.2%) formed colonies of similar appearance and morphology, and 48 (34.8%) formed colonies which differed either in appearance or morphology . The individual colonies of 138 isolates were tested for serotype . The former 90 isolates formed only the colonies with one kind of serotype, whereas 17 of the latter 48 isolates formed the colonies with more than one kind of serotype . All the 9 isolates tested also differed in other biochemical characteristics: acid productions from xylose, mannitol and maltose, urease production and gelatin liquefaction . beta-Lactamase activity was investigated in 7 isolates forming colonies with more than one serotype . There were no marked differences in beta-lactamase activity among the different colonies in 5 isolates but marked differences among those in the other 2 isolates. Matrix Suppl, 1992, 1, 259 - 62 Inhibition of human skin fibroblast collagenase by phosphorus-containing peptides; Galardy RE et al.; Substitution of the phosphonamidate linkage (PO2-NH) for the peptide bond (CO-NH) in substrate-like sequences produces inhibitors of human skin fibroblast collagenase with Ki's far below Km for the native collagen substrate . Using a thiol ester substrate at pH 6.5, phthaloyl-GlyP-Ile-Trp-(S)NHCH-(Me)Ph, the phosphonamidate analog of phthaloyl-Gly-Ile-Trp-(S)NHCH(Me)Ph, has a Ki of 20 nM . Peptide phosphonamidates with amino acid sequences extended further to the right or the left of the Gly-Ile-Trp sequence had higher Ki's . Substitution of the phosphinate linkage (PO2-CH2) for the peptide bond also gives potent inhibitors such as napthoyl-GlyP-C-Leu-Trp-NHBzl, the phosphinate analog of naphtholyl-Gly-Leu-Trp-NHBzl, which has a Ki of 10 nM . Some of the phosphonamidates and phosphinates are also excellent inhibitors of the bacterial zinc metalloproteases thermolysin and Pseudomonas aeruginosa elastase. Matrix Suppl, 1992, 1, 112 - 5 Crystallographic structures of the elastase of Pseudomonas aeruginosa; McKay DB et al.; The elastase protein of Pseudomonas aeruginosa is a zinc metalloprotease which has been shown to be a member of the bacterial neutral protease family . Its overall tertiary structure is similar to that of thermolysin . The x-ray crystallographic structure of the elastase has been solved to high resolution in three different crystal forms . Substantial conformational differences are observed in the protein in different crystal forms . In the absence of ligand, and independently in the presence of a covalent noncompetitive inhibitor, the elastase is observed to have a relatively "open" substrate binding cleft, while in the presence of tight-binding competitive inhibitors, the active site cleft is "closed". Surg Today, 1992, 22(6), 504 - 7 Bacterial adherence to human gallbladder epithelium; Sakurai S et al.; The adherence of Escherichia coli and Pseudomonas aeruginosa to the epithelium of the gallbladders obtained from 32 patients with negative bile culture was quantified by a scanning electron microscope . Of the gallbladders, 5 were histologically normal (group A), 21 had chronic calculus cholecystitis (group B), and 6 had acute calculus cholecystitis (group C) . The data were expressed as the mean +/- S.D . of the numbers of adherent bacteria to 1,000 microns2 of the gallbladder epithelium . The number of adherent E . coli were 0.1 +/- 0.2 in group A, 4.2 +/- 2.8 in group B, and 9.2 +/- 3.3 in group C . A similar result was also observed with P . aeruginosa . The number of adherent bacteria, both of E . coli and P . aeruginosa were significantly higher in group C than in groups A and B, and were also significantly higher in group B compared to group A . The amount of bacterial adherence paralleled that of the degree of epithelial damage, and the normal epithelium proved to have an inhibiting ability . Thus, a secondary bacterial infection is more likely to happen in patients with contaminated bile, and therefore, the treatment for acute cholecystitis should be based either on the results of a bile culture or according to predictive factors for bactibilia. Microbios, 1992, 72(290), 7 - 16 Sensitivity of Pseudomonas stutzeri to EDTA: effects of growth parameters and test conditions; Temple GS et al.; EDTA is highly toxic for Pseudomonas stutzeri . The bactericidal effect is not significantly attenuated by treatment of the cells at 0 degrees C rather than 25 degrees C, nor by osmotic stabilisation of the treated cells . The few surviving cells are not genetically resistant, but resistance to EDTA (and to some cationic antibiotics) can be induced by growing organisms in magnesium-limited media . Under these conditions, there is increased production of a protein of molecular mass about 20 kD . Comparable results have been reported for Pseudomonas aeruginosa . The mode of action of EDTA on these pseudomonads is discussed. Intensive Care Med, 1992, 18(7), 430 - 2 Fulminant primary Pseudomonas aeruginosa pneumonia and septicaemia in previously well adults; Henderson A et al.; We report two cases of primary, community acquired, Pseudomonas aeruginosa pneumonia, occurring in previously well adults without any recognisable environmental risk factors . Both patients died within 36 h of the onset of symptoms, despite broad spectrum antibiotics and aggressive supportive care . In neither case was the diagnosis considered in life and neither patient received adequate anti-pseudomonas therapy . Heightened awareness of this rare, fulminant, variant of primary Pseudomonas pneumonia is required if specific anti-pseudomonas therapy is to have any impact on outcome. Agents Actions Suppl, 1992, 38 ( Pt 3), 329 - 42 Hageman factor dependent activation and its relationship to lethal Pseudomonas aeruginosa burn wound infections; Holder IA et al.; Trauma causes increases in total protease load in the circulation of the traumatized host animal or patient . This increase is due, in part, to Hageman Factor activation followed by down-line cascade system activation . Concomitant with the activation of these systems is a reduced host capacity to resist infection . Infection superimposed on a traumatized host increases the total host protease load even more by additional activation of Hageman Factor and cascade systems. Dev Biol Stand, 1992, 77, 121 - 8 Protodyne: an immunostimulatory protein component, prepared from gram-positive Bacillus subtilis; Houba V et al.; A protein component derived from bacterial protoplasm, called Protodyne, increases the non-specific resistance to infections by bacteria and viruses . Here we show that Protodyne can be prepared not only from Gram-negative bacteria, but also from Gram-positive bacilli . Several preparations of Protodyne, prepared from Bacillus subtilis by phenol extraction or by ammonium sulfate precipitation, were evaluated for immunomodulatory activities in a variety of assays . Protodyne had a marked mitogenic activity on mouse spleen cells; it was a potent inducer of tumor necrosis factor (TNF) and stimulated production of interleukin-1 (IL-1) in human peripheral blood mononuclear cells; it increased the capacity of activated macrophages to undergo a respiratory burst, to produce intracellular killing of leishmanial parasite and extracellular lysis of mastocytoma cells; it also stimulated phagocytosis of latex particles, and prolonged survival of immunosuppressed mice infected with Pseudomonas aeruginosa . These activities were not inhibited by polymyxin B, indicating that the activity of Protodyne is not the result of contamination with exogenous lipopolysaccharide . It appears that Protodyne exerts its many immunomodulatory actions by inducing the release of soluble mediators, including TNF and IL-1. Microbios, 1992, 70(284-285), 215 - 30 Mechanism of action of chlorhexidine diacetate and phenoxyethanol singly and in combination against gram-negative bacteria; Fitzgerald KA et al.; Chlorhexidine diacetate and the aromatic alcohol, phenoxyethanol in combination had an enhanced bacteriostatic action against Escherichia coli and Pseudomonas aeruginosa strains . Investigations of potassium (K+) ion leakage by means of a potassium electrode and a radioactive method, employing 86Rb, indicated that the combination accelerated the rate of leakage from the cell . Leakage of pentose was also found to be enhanced in the presence of the combination compared with either drug alone. C R Acad Sci III, 1992, 314(13), 587 - 92 {Fragmentation of fibronectin in cystic fibrosis}; Allal M et al.; Fibronectin (FN) plays an important role in mediating cell-matrix interactions and also as an opsonin in the phagocytosis of some microorganisms . Due to its domain structure FN is easily attacked by proteolytic enzymes and especially by elastases . Some of the fragments possess original properties as potentiation of viral transformation or proteolytic activity absent in the intact molecule . Cystic fibrosis is frequently accompanied by infection with protease generating microorganisms, such as Pseudomonas aeruginosa . Polyacrylamide gel electrophoresis and immunoblotting revealed the presence of FN fragments in the plasma of patients with molecular weight between 30 and 100 kD . Purified plasma FN was rapidly hydrolyzed in fragments by the sputum of patients as well as by purified Pseudomonas elastase . The comparison of fragments detected in patients' plasma with those produced by in vitro proteolysis confirms the probability of in vivo fragmentation of FN in cystic fibrosis and suggests that several proteolytic enzymes, endogenous and of bacterial origin, might be involved. Biomaterials, 1992, 13(7), 417 - 20 Surface-immobilized polyethylene oxide for bacterial repellence; Desai NP et al.; Polyethylene terephthalate films were surface-modified with polyethylene oxide (18,500 g/mol) using a solution technique described previously . These films were investigated for their resistance to bacterial adhesion . Three bacterial strains most commonly associated with implant infections, Staphylococcus epidermidis, Staphylococcus aureus and Pseudomonas aeruginosa, were cultured in tryptic soya broth, human plasma and human serum on the polymeric substrates . Significant reductions (between 70 and 95%) in adherent bacteria were observed on the polyethylene oxide-modified substrates compared to the untreated control polyethylene terephthalate . Surface modification with polyethylene oxide may reduce the risk of implant-associated infections . Plasma fibrinogen was observed to play an important role in the adhesion of all three of these species on both the polyethylene oxide-modified and control polyethylene terephthalate materials. Kansenshogaku Zasshi, 1992 Jan, 66(1), 76 - 80 Effect of recombinant human granulocyte colony-stimulating factor (G-CSF) in the treatment of Pseudomonas aeruginosa bacteremia complicating hematologic malignancy--a preliminary study; Funada H et al.; The efficacy of recombinant human granulocyte colony-stimulating factor (G-CSF) in the treatment of Pseudomonas aeruginosa bacteremia in cancer patients receiving intensive chemotherapy was studied retrospectively . In 14 of the 24 episodes of P . aeruginosa bacteremia, which occurred in 23 severely neutropenic patients with hematologic malignancies during a three-year period, G-CSF was given subcutaneously or intravenously at daily doses of 75 micrograms/body to 200 micrograms/m2 of body surface . Overall, survival at one week after onset was observed in 13 patients (54%) . Treatment with G-CSF, however, had no statistically significant association with one-week survival, although a favorable outcome was well correlated with an increase in the neutrophil count during therapy . On the other hand, septic shock and appropriate antibiotic therapy were the major prognostic factors . The frequency of shock was reduced by appropriate therapy, but not by G-CSF treatment . These preliminary findings thus suggested that G-CSF should not be effective in the treatment of neutropenic cancer patients with P . aeruginosa bacteremia . No adverse effects of G-CSF were observed. Jpn J Antibiot, 1992 Jan, 45(1), 98 - 105 {Combination effect of KW-2228 and aminoglycoside antibiotics on systemic infection in cyclophosphamide-treated tumor-bearing mice}; Yoshino T et al.; A modified recombinant human granulocyte colony-stimulating factor (rhG-CSF), KW-2228, has some excellent properties such as high specific activity in stimulating granulocyte colony-formation in vitro, great biological stability in plasma, good pharmacokinetic profile and high potency in granulopoiesis in normal mice in vivo . Recently, the application of G-CSF against infectious diseases has been considered, and some animal experiments have been carried out to support its clinical applications . Patients with underlying diseases such as leukemia and cancer often have recurrent infections because of reduced numbers or functions of neutrophils, which mediate an early stage of host defense . In out present study, we established a new method to evaluate in vivo potency of G-CSF in colon 26 tumor-bearing mice . By using the method, we examined combination effects of KW-2228 with aminoglycoside antibiotics against a systemic infection caused by Pseudomonas aeruginosa . KW-2228 (1 microgram/mouse/day) was administered (s.c.) once a day for 4 days before the bacterial infection was introduced in colon 26 tumor-bearing mice receiving cyclophosphamide 3 days after the transplantation of tumor . Antibiotics were administered (s.c.) 2 hours after the introduction of the bacterial infection . ED50 of gentamicin (GM) alone and that of the combination with KW-2228 were 40.7 mg/kg and 3.6 mg/kg, respectively . ED50 of astromicin (ASTM) alone and that of the combination with KW-2228 were 386 mg/kg and 17.8 mg/kg, respectively . Thus the combination therapy of KW-2228 with GM or ASTM exhibited excellent protective effects in comparison to the treatment with antibiotic alone.(ABSTRACT TRUNCATED AT 250 WORDS) Jpn J Antibiot, 1992 Jan, 45(1), 87 - 90 {Protective effect of KW-2228 in a systemic infection model of CPA-treated tumor-bearing mice}; Yoshino T et al.; A modified recombinant human granulocyte colony-stimulating factor (rhG-CSF), KW-2228, has some excellent properties such as high specific activity in stimulating granulocyte colony-formation in vitro, great biological stability in plasma, good pharmacokinetic profile and high potency in granulopoiesis in normal mice in vivo . Recently, the application of G-CSF against infectious diseases has been considered, and some animal experiments have been carried out to support its in clinical applications . Patients with underlying diseases such as leukemia or cancer often have recurrent infections because of reduced number and functions of neutrophils, which mediate an early stage of host defense . We investigated the prophylactic effect of KW-2228 against an experimental systemic infection with Pseudomonas aeruginosa in tumor-bearing mice (colon 26: BALB/c) treated with cyclophosphamide . KW-2228 (0.25-2.0 micrograms/mouse) was administered (s.c.) once a day for 4 days before the experimental bacterial infection . As a result of KW-2228 administration, the reduction in peripheral blood neutrophils usually caused by the injection with cyclophosphamide was prevented markedly . KW-2228 displayed excellent protective potency dose-dependently against the infection with P . aeruginosa in tumor-bearing mice . These data show the possibility that prophylactic therapy with KW-2228 may augment the host defense of immunocompromised patients to infections . It present, clinical efficacy studies on KW-2228 are under way. J Bacteriol, 1992 Jan, 174(2), 471 - 6 Overexpression in Escherichia coli and functional analysis of a novel PPi-selective porin, oprO, from Pseudomonas aeruginosa; Hancock RE et al.; Immediately upstream from and adjacent to the oprP gene, which codes for the phosphate-specific porin OprP of Pseudomonas aeruginosa, lies the PR region (oprO), which cross-hybridizes with oprP DNA . To determine the function of this region, the oprO gene was expressed behind the lactose promoter in Escherichia coli, and the resultant OprO protein was purified and reconstituted into planar lipid bilayers . OprO formed sodium dodecyl sulfate-stable trimers, cross-reacted immunologically with OprP, and, like OprP, formed an anion-specific, phosphate-selective porin . However, it demonstrated lower affinity for and higher maximal conductance of both chloride and phosphate than did the OprP channel . Examination by macroscopic conductance inhibition experiments of the affinity of OprO for phosphates of different lengths revealed a preference for PPi and tripolyphosphate over Pi, suggesting that OprO functioned as a PPi-selective polyphosphate channel, in contrast to OprP, which has a marked preference for Pi. Adv Perit Dial, 1992, 8, 325 - 7 Exit-site/tunnel infection and catheter outcome in peritoneal dialysis patients; Wadhwa NK et al.; STUDY OBJECTIVE: To study exit-site/tunnel infections and catheter outcomes in peritoneal dialysis patients . DESIGN: The study was designed to investigate exit-site (ESI)/tunnel infections (TI) and catheter losses in all chronic PD catheters inserted in ESRD patients from 9/88 to 9/91 . SETTING: Tertiary-referral university hospital . PATIENTS AND METHODS: Seventy-three patients (40 males, 33 females) underwent 78 double-cuff coiled swan-neck catheter implantations surgically . The curettage of exit site was performed weekly for tunnel infection refractory to medical management . The subcutaneous cuff was excised in persistent ESI/TI . RESULTS: Fifty-nine episodes of ESI/TI in 34 patients were observed over 946 patient-months . Thirty-nine patients experienced no ESI/TI, 27 patients had one and seven had two or more episodes of ESI/TI . Four patients had five episodes of peritonitis associated with ESI/TI . Eight recurrent episodes of ESI/TI with S . aureus in 8 patients were treated successfully with Rifampin . Seven subcutaneous cuffs were excised successfully in 7 patients with tunnel infection, five with S . aureus and two with Pseudomonas aeruginosa . No catheter was removed due to ESI/TI or ESI/TI associated peritonitis . CONCLUSIONS: Aggressive exit site care including repeated curettage, excision of the subcutaneous cuff and appropriate antibiotics reduced significantly catheter losses related to ESI/TI. Zh Mikrobiol Epidemiol Immunobiol, 1992 Jan, (1), 16 - 8 {The hemagglutinating properties of Pseudomonas aeruginosa strains isolated from patients with nonspecific lung diseases}; Dalina AM et al.; To detect d-mannose-sensitive (MS) pili in 31 P . aeruginosa strains isolated from the respiratory tract of patients with inflammatory and purulent destructive pulmonary diseases, the hemagglutination (HA) test was used . The isolated Pseudomonas under study differed in the degree of manifestation of their MS adhesins . Among them microorganisms with pronounced HA activity (high HA titer) occurred, as well as those whose HA activity was less pronounced (low HA titer) . P . aeruginosa strains with pronounced HA activity were more frequently isolated from patients with purulent destructive processes in the lungs . A correlation between the state of the patient at the moment of bacteriological examination and the degree of manifestation of MS pili in the P . aeruginosa strain isolated from this patients was established . The value of HA titer in the presence of d-mannose is indicative of the presence of MS adhesins in a P . aeruginosa strain. Mem Inst Oswaldo Cruz, 1992, 87 Suppl 5, 61 - 8 Pseudomonas aeruginosa adhesion to normal and injured respiratory mucosa; Plotkowski MC et al.; Human nasal polyps in outgrowth culture were used to study the adhesion of Pseudomonas aeruginosa to respiratory cells . By transmission electron microscopy, bacteria associated with ciliated cells were identified trapped at the extremities of cilia, usually as aggregates of several bacterial cells . They were never seen at the interciliary spaces or attached along cilia . Bacteria were also seen to adhere avidly to migrating cells of the periphery of the outgrowth culture . Using a model of repair of wounded respiratory epithelial cells in culture, we observed that the adhesion of P . aeruginosa to migrating cells of the edges of the repairing wounds was significantly higher than the adhesion to non-migrating cells and that adherent bacteria were surrounded by a fibronectin-containing fibrillar material . The secretion of extracellular matrix components is involved in the process of epithelium repair following injury . To investigate the molecular basis of P . aeruginosa adhesion to migrating cells, bacteria were treated with a fibronectin solution before their incubation with the respiratory cells . P . aeruginosa treatment by fibronectin significantly increased their adhesion to migrating cells . Accordingly, we hypothesize that during cell migration, fibronectin secreted by epithelial cells may favour P . aeruginosa adhesion by establishing a bridge between the bacteria and the epithelial cell receptors . Such a mechanism may represent a critical step for P . aeruginosa infection of healing injured epithelium. Drugs Exp Clin Res, 1992, 18(7), 291 - 4 In vitro and in vivo evaluation of BMY 45243, a new 5-amino-naphthyridone derivative; Bouzard D et al.; BMY 45243 is the first representative of 5-amino naphthyridone derivatives prepared following a new methodology developed by the authors . BMY 45243 is a highly lipophilic compound, very active in vitro and in vivo on S . aureus and was found to be as potent as ciprofloxacin on Gram-negative organisms with identical in vivo activity against Pseudomonas aeruginosa . Pharmacokinetics in mice showed better AUC and Cmax and longer t1/2 for BMY 45243 than for sparfloxacin and ciprofloxacin. Int Arch Allergy Immunol, 1992, 99(1), 98 - 106 Alginate--its role in neutrophil responses and signal transduction towards mucoid Pseudomonas aeruginosa bacteria; Konig B et al.; Mucoid Pseudomonas aeruginosa bacteria impaired neutrophil functions, e.g . chemiluminescence response, and leukotriene formation to a significantly higher degree as compared to nonmucoid P . aeruginosa bacteria . To study the cell biological requirements for the different cellular response pattern by mucoid and nonmucoid (NM) P . aeruginosa bacteria, further experiments were performed with purified alginate, the mucoid exopolysaccharide of P . aeruginosa (MEP) . In this regard the MEP (alginate) significantly reduced the zymosan-induced leukotriene B4 (LTB4) formation (from 40 +/- 7 to 2 +/- 4 ng) . The chemiluminescence response induced by NM bacteria was abolished when the bacteria were precoated with the MEP . Mucoid and NM P . aeruginosa bacteria interacted with components of the cellular signal transduction pathway to a different degree . Mucoid bacteria induced a 2-fold enhanced GTPase activity but activated the protein kinase C (PKC) to a lesser degree than NM P . aeruginosa bacteria . Prior exposure of neutrophils to the MEP increased the sodium fluoride (NaF)-induced GTPase activity and guanylylimidodiphosphate binding {Gpp(NH)p} by approximately 60 and 30%, respectively . The phorbol myristic acid-induced PKC activation was inhibited by 30-40% in the presence of the MEP . However, the MEP by itself was inactive in all assay systems . Our results indicate that the MEP represents an important component which modulates neutrophil responses of mucoid as compared to NM P . aeruginosa bacteria, e.g . the chemiluminescence response, LTB4 generation, and the interaction with components (G proteins, PKC) of the signal transduction pathway. FEMS Microbiol Lett, 1992 Jan 1, 69(2), 205 - 9 NAD-dependent glutamate dehydrogenase from Pseudomonas aeruginosa is a membrane-bound enzyme; Joannou CL et al.; Measurements of the deaminating activity of NAD-dependent glutamate dehydrogenase (NAD-GDH) in Pseudomonas aeruginosa strain 8602 (PAC 1) showed an initially constant rate that gave way to a 3.5-fold increased rate on prolonged incubation . Only the faster rate was observed when assay mixtures were preflushed with nitrogen or were treated with the detergent Triton X-100 . Comparison of the intracellular distribution of NAD-GDH with marker enzymes showed it to be associated with the cytoplasmic membrane . The results suggest that NAD-GDH may be linked to oxygen through an electron-transport system. Proc Natl Acad Sci U S A, 1992 Jan 1, 89(1), 47 - 51 Components of the protein-excretion apparatus of Pseudomonas aeruginosa are processed by the type IV prepilin peptidase; Nunn DN et al.; In the Gram-negative pathogen Pseudomonas aeruginosa, mutants in the gene for the prepilin peptidase (pilD) are pleiotropic, as they not only fail to process pilin but also accumulate in the periplasm, in their mature form, several toxins and hydrolytic enzymes that are normally exported to the external medium (excreted) . We have suggested that this excretion defect is due to the lack of PilD-dependent processing of proteins that share sequences in common with the prepilin subunit and that are components of a protein-excretion machinery . In this paper we report the isolation and characterization of transposon-induced excretion mutants with phenotypes similar to that of a pilD gene mutant . Using oligonucleotide probes designed to recognize sequences encoding the cleavage site of the type IV prepilins, we have isolated four linked genes with the predicted putative PilD-dependent cleavage site . Site-specific mutations within these genes have shown that they are required for protein excretion, and PilD-dependent processing of at least one of the four encoded proteins was demonstrated . Evidence suggests that similar components play a role in protein excretion in a wide variety of Gram-negative bacteria. Plant J, 1992 Jan, 2(1), 129 - 31 Molecular characterization of glutathione reductase cDNAs from pea (Pisum sativum L.); Creissen G et al.; A cDNA for pea glutathione reductase has been cloned and sequenced . The derived amino acid sequence of 562 residues shows a high degree of homology to the previously published GR sequences from human erythrocytes and from two prokaryotes: Escherichia coli and Pseudomonas aeruginosa . The pea enzyme differs from other GRs in having an N-terminal leader sequence of about 60-70 residues which may be a chloroplast transit peptide and a 20 amino acid C-terminal extension of unknown function. Ann Radiol (Paris), 1992, 35(6), 494 - 9 {Atypical osteomyelitis of the base of the skull and malignant otitis externa}; Sanhaji L et al.; Osteomyelitis of the skull base is a rare, but serious disease whose incidence is tending to increase . It affects the marrow of the temporal, occipital and sphenoid bones and is generally secondary to Pseudomonas aeruginosa infection of the external auditory meatus . Based on a clinical case, the authors recall the difficulty of establishing the positive diagnosis and the possible confusion with neoplastic disease, hence the fundamental role of biopsies . They also review the literature on this subject. Scand J Infect Dis, 1992, 24(6), 815 - 7 Isolated severe thrombocytopenia and bleeding caused by piperacillin; Olivera E et al.; Bleeding and severe thrombocytopenia developed in a 71-year-old man who had been receiving piperacillin 5 g intravenously every 8 h for 9 days for the treatment of Pseudomonas aeruginosa septicemia . After piperacillin was discontinued, the platelet counts became normal . Rechallenge was made with 2 g of piperacillin intravenously resulting in thrombocytopenia within 6 h of piperacillin administration . The platelet count normalized after 3 days when no further piperacillin was given. Scand J Infect Dis, 1992, 24(6), 797 - 800 Long-term oral ciprofloxacin in the treatment of prosthetic valve endocarditis due to Pseudomonas aeruginosa; Uzun O et al.; Prosthetic valve endocarditis caused by Pseudomonas aeruginosa is refractory to medical treatment alone and early valve replacement is necessary . We describe a 40-year-old patient in whom endocarditis developed in the early postoperative period, and reoperation was not considered feasible . Ciprofloxacin was administered orally in order to suppress bacteremia for 36 months . Long-term oral ciprofloxacin may provide an opportunity in the treatment of prosthetic valve endocarditis caused by Ps . aeruginosa in patients who are unfavorable candidates for reoperation. Med Microbiol Immunol (Berl), 1992, 181(6), 339 - 49 Determination of IgG subclass antibodies to Pseudomonas aeruginosa outer membrane proteins in cystic fibrosis lung infection using immunoblotting and enzyme-linked immunosorbent assay; Pressler T et al.; IgG subclass antibodies to Pseudomonas aeruginosa outer membrane proteins (OMP) were investigated in serum from cystic fibrosis (CF) patients by immunoblotting and enzyme-linked immunosorbent assay (ELISA) . Fifteen patients (eight in good and seven in poor clinical condition) have been followed for an average of 13 years with multiple serum samples covering the preinfection, and early and late stages of chronic infection . Laser-scanning densitometry of photographs taken from immunoblots was used to quantify antibody level and compare with ELISA titres . The earliest anti-OMP antibodies to appear were of the IgG1 subclass . There was no significant difference in IgG subclass antibody levels to OMPs between patients in relatively good and poor clinical condition . Data presented indicate a high positive correlation among measurements of IgG subclass antibodies to P . aeruginosa OMPs using ELISA and immunoblotting. Microbiol Immunol, 1992, 36(12), 1305 - 16 Establishment of stable cell lines producing anti-Pseudomonas aeruginosa monoclonal antibodies and their protective effects for the infection in mice; O'Oka H et al.; Human-human hybridomas producing monoclonal antibodies (MoAbs) specific for five major serotypes of Pseudomonas aeruginosa were developed by fusing P . aeruginosa primed and Epstein-Barr virus-transformed cells with human myeloma P109 cells using polyethyleneglycol . The MoAbs which were produced by the hybridomas were protective against lethal intraperitoneal (i.p.) challenge of P . aeruginosa (10 LD50) in mice . The 50% effective dose (ED50) values of MoAbs ranged from 0.5 to 10.2 micrograms/mouse and were 26 to 240 times more protective than a commercial human IgG preparation . MoAb administration to mice promoted bacterial clearance in peritoneal cavity, and prevented bacterial invasion into blood in the way of increasing both the number of bacteria trapped by a macrophage and the ratio of macrophages that trapped bacteria . MoAbs also showed protective effects against lethal infection of P . aeruginosa in the mice which were decreased in polymorphonuclear cells (PMN) by cyclophosphamide (CY) . All MoAbs showed serotype-specific binding to the clinical isolates of P . aeruginosa as well as to the immunized strains . The hybridoma cell lines maintained their capacity to produce MoAb continuously for more than 12 months and produced 10 to 60 micrograms MoAbs per 10(6) cells in 24 hr . It is practicable to use these cell lines for large-scale production of anti-P . aeruginosa MoAbs and such MoAbs must be useful for the therapeutics of patients with P . aeruginosa infection. Eur J Biochem, 1991 Dec 18, 202(3), 1275 - 82 Hypochlorous acid and myeloperoxidase-catalyzed oxidation of iron-sulfur clusters in bacterial respiratory dehydrogenases; Hurst JK et al.; Hypochlorous acid and related oxidants derived from myeloperoxidase-catalyzed reactions contribute to the microbicidal activities of phagocytosing neutrophils and monocytes . Microbial iron-sulfur (Fe/S) clusters have been suggested as general targets of myeloperoxidase-derived oxidations, but no susceptible Fe/S site has yet been identified . In this study, the effects of HOCl and myeloperoxidase-catalyzed peroxidation of chloride ion upon EPR-detectable Fe/S clusters in Escherichia coli and Pseudomonas aeruginosa were examined . Increasing amounts of oxidant produced progressive loss of signal amplitudes from the S-1 and S-3 Fe/S clusters of succinate:ubiquinone oxidoreductase in respiring membrane fragments . These changes were compared to loss of microbial viability, succinate uptake rates, succinate dehydrogenase activity and succinate-dependent respiration . The amounts of oxidant required to destroy Fe/S clusters exceeded the amounts required to kill organisms or inhibit respiratory function by factors of four or five . Power saturation characteristics of the S-1 signal indicated that the S-2 signal was also resistant to modification, even in highly oxidized membranes . Loss of succinate-dependent respiration was closely associated with HOCl and myeloperoxidase-mediated microbicidal activity against P . aeruginosa and was also an early event in the oxidant-mediated metabolic dysfunctions of E . coli . However, these effects were not caused by the destruction of the Fe/S clusters within the succinate:ubiquinone oxidoreductase . Rather, the major respiration-inhibiting lesion(s) appeared to reside at points in the respiratory chain between the Fe/S clusters and the ubiquinone reductase site. J Mol Biol, 1991 Dec 20, 222(4), 869 - 71 Crystallization of and preliminary X-ray data for the negative regulator (AmiC) of the amidase operon of Pseudomonas aeruginosa; Wilson SA et al.; The negative regulator (AmiC) of the amidase operon of Pseudomonas aeruginosa has been purified from an over-expressing clone and crystalized . Crystals of diffraction quality were obtained from polyethylene glycol 4000 and ammonium sulphate . AmiC crystallizes in P4(2)2(1)2 (a = 104.4 A, c = 66.6 A) with one subunit in the asymmetric unit . Crystals diffract beyond 2.8 A. FEMS Microbiol Lett, 1991 Dec 15, 69(1), 43 - 8 A plasmid from a virulent strain of Legionella pneumophila is conjugative and confers resistance to ultraviolet light; Tully M; The presence of a single apparently cryptic plasmid of approximately 36 MDa was demonstrated in the virulent Dodge strain of Legionella pneumophila . 'Tagging' of the plasmid with Tn5 enabled transfer to be demonstrated to other strains of Legionella (though not to Escherichia coli or Pseudomonas aeruginosa) as well as a definitive assessment to be made of its stability . Plasmid carriage confers resistance to UV light probably by means of an error-prone UV repair system . The plasmid is compatible with plasmids of the IncP and IncW incompatibility groups. Am J Kidney Dis, 1991 Dec, 18(6), 674 - 7 Exit-site and tunnel infections in continuous ambulatory peritoneal dialysis patients; Scalamogna A et al.; One hundred two exit-site infections (ESI) were diagnosed in 63 of 163 (38.6%) patients, with an incidence of one episode every 23.7 patient-months in patients with a history of ESI, whereas in the overall continuous ambulatory peritoneal dialysis (CAPD) population the incidence was one episode every 48.7 patient-months . In diminishing order of frequency, the bacteria isolated were Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Escherichia coli . The probability of remaining free of ESI was 72% at 1 year and 45% at 5 years . The ESI that led to catheter removal were due to S aureus and gram-negative rods . In 13 (48%) of 27 S aureus ESI unresponsive to antibiotics and local care, deroofing and outer cuff shaving completely resolved the ESI . Despite this treatment, the catheters of the remaining 14 patients had to be removed because of peritonitis associated with the tunnel infection . In conclusion, ESI is a major cause of CAPD failure . In our series, shaving the cuff as a rescue treatment was effective for almost 50% of the patients with antibiotic-resistant S aureus ESI. Chest, 1991 Dec, 100(6), 1607 - 13 Role of chronic Pseudomonas aeruginosa infection in airway mucosal permeability; Ishihara H et al.; The role of Pseudomonas aeruginosa infection in airway mucosal permeability was studied in 16 patients with chronic bronchitis by measuring the amounts of radiolabeled albumin in sputum . One group (A) consisted of six patients (two female, four male, 53 +/- 6 years, SEM) with chronic P aeruginosa infection for 5 +/- 0.9 years . Another group (B) consisted of ten patients (five female, five male, 67 +/- 4 years) without P aeruginosa infection for at least two years . No significant differences between groups A and B were found in the volume of sputum (63 +/- 21 ml/day in group A and 45 +/- 8 ml/day in group B, p = 0.44), the obstructive changes (FEV1 of 57 +/- 6 percent in group A and 51 +/- 4 percent in group B), or the duration of disease (19 +/- 4 years in group A and 14 +/- 4 years in group B) . Saliva, sputum, and serum samples were collected at intervals of 2 h over an 8-h period, and at 24 h after intravenous administration of 131I-labeled human albumin . For counting, free 131I was removed by dialysis . Radiocounts (cpm) of saliva were significantly smaller than those of sputum or serum . The cpm from each sputum sample was divided by serum cpm at the time of each sampling . Group A showed significantly higher values in the ratio of sputum- to serum-cpm than did group B at all sampling times . Furthermore, the ratios at 2 and 4 h after 131I-albumin injection significantly correlated with sputum volume per day, whereas they did not correlate with any other factors (age, obstructive impairment, and duration of disease) . These findings suggest that chronic P aeruginosa infection produces an increase in airway mucosal permeability to albumin. Am J Respir Cell Mol Biol, 1991 Dec, 5(6), 563 - 70 Characterization of Pseudomonas aeruginosa adherence to cultured hamster tracheal epithelial cells; Grant MM et al.; This study reports an in vitro system that allows the convenient study of both microenvironmental and bacterial factors affecting adherence of Pseudomonas aeruginosa to tracheal epithelium . Primary cultures of mixed ciliated and nonciliated epithelial cells isolated from hamster tracheas were grown on collagen-coated multiwell plates containing 10(5) epithelial cells/well at confluence . When 10(7) 14C-labeled P . aeruginosa (nonmucoid, strain Y-4) suspensions were added to each well, 8.13 +/- 2.6% (mean +/- SD) of the initial inoculum bound to the cultured cells, an amount comparable to that measured using suspensions of human tracheal epithelial cells and the same bacteria . The bacteria adhered preferentially to the cultured cells rather than to an acellular collagen matrix . Five additional nonmucoid strains of P . aeruginosa also bound well to the cultured cells, while two mucoid strains were less adherent . Strains of two other gram-negative bacteria, Pseudomonas maltophilia and Klebsiella pneumoniae, did not bind significantly, emphasizing the bacterial species specificity of the adherence interaction being measured . The binding interaction with P . aeruginosa was both pH-sensitive and altered by the presence of the divalent cation calcium . Thus, the in vitro assay system described provides a consistent surface of tracheal epithelial cells that binds P . aeruginosa in a specific manner and can be used to examine the effects of bacterial variables and microenvironmental conditions that may be present in the human airway. J Chemother, 1991 Dec, 3(6), 363 - 6 Indirect transfer of resistance to imipenem in a strain of Pseudomonas aeruginosa; Krcmery V et al.; Determinants of resistance of imipenem can be, in Pseudomonas aeruginosa strains resistant to this drug, transferred by transduction with wild-type phages as well as mobilized for conjugal transfer, as demonstrated by the indirect selection procedure . Exconjugants obtained in the latter type of experiments do not transfer imipenem resistance determinant to further recipient strains(s) by conjugation . Mobilized imipenem resistance is of non-hydrolytic character and its biochemical mechanism is unknown at present. J Antimicrob Chemother, 1991 Dec, 28(6), 869 - 75 The resistance patterns and serotypes of Pseudomonas aeruginosa strains isolated from children; Patzer J et al.; Among 916 Pseudomonas aeruginosa strains isolated from children in a Warsaw hospital during the period 1985-1988 the most frequently encountered serotypes were O6, O11, O12, and O16 . The majority of isolates resistant to aminoglycosides were characterized by simultaneous resistance to gentamicin and tobramycin and belonged to serotype O11 . Among isolates resistant to beta-lactam antibiotics the most frequently encountered serotype was O6, followed by serotype O3 and O11 . Most strains of serotype O12 were resistant to aminoglycosides and beta-lactam antibiotics as has been reported from other countries. Antimicrob Agents Chemother, 1991 Dec, 35(12), 2649 - 51 Development of resistance to ciprofloxacin in nutrient-rich and nutrient-limited growth conditions in vitro by Pseudomonas aeruginosa isolates from patients with cystic fibrosis; Ferguson MI et al.; Five serial exposures of mucoid Pseudomonas aeruginosa from patients with cystic fibrosis to subinhibitory concentrations of ciprofloxacin resulted in stepwise increases in the MIC, with a mean proportional increase of 10 . MICs were significantly lower in an iron-limited chemically defined medium than in Iso-Sensitest broth . The mucoid phenotype was maintained in chemically defined medium . Acquired resistance was retained either partially or completely in 85% of the isolates following 10 transfers in drug-free media . In cases in which susceptibility was regained, an increase in the MIC was observed on one further exposure to ciprofloxacin. Antimicrob Agents Chemother, 1991 Dec, 35(12), 2617 - 24 Impact of pH and cationic supplementation on in vitro postantibiotic effect; Gudmundsson A et al.; Most studies on pharmacodynamic variables in vitro, including the postantibiotic effect (PAE), are performed at pH 7.4 in noncationic-supplemented media, a situation which may differ significantly from the true microenvironment in most infected foci . We studied the impact of five different pH levels (pH 5, 6, 7, 7.4, and 8) on the duration of the PAE, the MIC, and bactericidal activity . Acid pH was found to have in general a deleterious effect on the activity of aminoglycosides and ciprofloxacin against Escherichia coli and Pseudomonas aeruginosa, with the MIC being higher, the bactericidal rate being lower, and the PAE being shorter at pH 5 (and to a lesser extent at pH 6) than at more alkaline pH levels . Similar results were observed for imipenem against P . aeruginosa . The PAEs induced by ampicillin against E . coli and dicloxacillin against Staphylococcus aureus were not predictably dependent on the pH, whereas the PAEs induced by ciprofloxacin against S . aureus were longest at either end of the pH spectrum . The bactericidal activity of these agents was, however, pH dependent, being slower at acid pHs . The addition of 50 mg of Ca2+ and 20 mg of Mg2+ per liter of liquid medium at pH 7.4 did not affect the duration of the PAE . Since the pH in abscess cavities may be close to 5, these observations may be of importance for employment of the agents studied in closed or poorly drained infections. Berl Munch Tierarztl Wochenschr, 1991 Dec 1, 104(12), 414 - 9 {Activation of the resident microbial flora as a possibility for the improvement of humoral antibody potentials}; Lubke A et al.; The effect of a parenteral application of an adjuvant (Propionibacterium acnes) and an adjuvant/antigen combination (Staphylococcus aureus Cowan I/Al(OH)3, Pseudomonas aeruginosa/Al(OH)3 respectively, was tested with regard to the improvement of antibacterial resistance . Parameter was the humoral antibody production (IgG) of rabbits against six facultative pathogen bacterial species (St . aureus, Sc . faecium, Bac . cereus, P . multocida, E . coli, Ps . aeruginosa) and against sheep rod blood cell membranes . The three methods of treatment led to a significant enhancement of IgG-antibodies against the particular homologous antigen . In addition to this specific reaction the application of adjuvant/antigen combinations provoked a significant enhancement of antibodies also against heterologous antigens (P . multocida, Bac . cereus, sheep red blood cell membranes) . The application of P . acnes had no distinct effect on the antibody titer against the different antigen preparations . In order to analyse the immune response qualitatively, a greater part of serum samples was examined by immuno blot technique . The number of partial antigens recognized by the sera increased during the experiments but the rise did generally not relate to developments of antibody titers . Nevertheless, the Ps . aeruginosa/Al(OH)3-treatment seemed to improve the ability of sera to detect antigenic determinants of heterologous bacterial species. J Antibiot (Tokyo), 1991 Dec, 44(12), 1371 - 93 Studies on condensed-heterocyclic azolium cephalosporins . I . Synthesis and antibacterial activity of 7 beta-{2-(2-aminothiazol-4-yl)-2(Z)- alkoxyiminoacetamido}-3-(imidazo{1,2-a}pyridinium-1-yl)methyl-3- cephem-4-carboxylates; Nishimura T et al.; In our study of the structure-activity relationships of cephalosporins bearing quaternary ammonium groups at the 3 position, we postulated that delocalization of the azolium positive charge would lead to an expanded antibacterial spectrum and increased activity . Since quaternization of condensed-heterocyclic compounds such as imidazo{1,2-a}pyridine gives positive charge delocalization, 7 beta-{2-(2-aminothiazol-4-yl)-2(Z)-alkoxyiminoacetamido} cephalosporin derivatives (1-53) bearing various (imidazo{1,2-a}pyridinium-1-yl)methyl moieties at the 3 position were prepared and their antibacterial activity was determined . As expected, these cephalosporins exhibited potent activity against both Gram-positive and Gram-negative bacteria including Pseudomonas aeruginosa . These results imply that imidazo{1,2-a}pyridine is a quite useful substituent for improving antibacterial activity and spectrum . The structure-activity studies revealed that a favorable substituent on the imidazo{1,2-a}pyridine is the cyano radical at the 6 position of the ring, and ethoxyimino or 1-carboxy-1-methylethoxyimino groups are suitable for the alkoxyimino substituent . Among the cephalosporins tested, 7 beta-{2-(2-aminothiazol-4-yl)-2(Z)- ethoxyiminoacetamido}-3-(6-cyanoimidazo{1,2-a}pyridinium -1-yl)methyl-3-cephem-4-carboxylate (45) and 7 beta-{2-(2-aminothiazol-4-yl)-2(Z)-(1- carboxy-1-methylethoxyiminoacetamido}-3-(6-cyanoimidazo{1,2- a} pyridinium-1-yl)methyl-3-cephem-4-carboxylate (49) showed good antibacterial activity. APMIS, 1991 Dec, 99(12), 1061 - 8 Experimental immunization with Pseudomonas aeruginosa alginate induces IgA and IgG antibody responses; Johansen HK et al.; We tried experimentally to induce a specific antibody response against Pseudomonas aeruginosa locally in the airways and systemically in rats by three different routes of immunization; intragastric feeding, intratracheal inoculation or subcutaneous vaccination . Three groups of rats were immunized with live mucoid P . aeruginosa PAO 579 by intragastric feeding or with killed PAO 579 intratracheally or subcutaneously . Three other groups were immunized with purified P . aeruginosa alginate either by intragastric feeding, intratracheally or subcutaneously . At weekly intervals for four weeks animals were sacrificed and serum and bronchial fluid were obtained . The specific IgA and IgG antibody response in lavage fluid and serum was measured . Only traces of antibodies could be detected in the bronchial lavage fluids . Anti-alginate IgA and IgG antibodies developed in all rats immunized with alginate but no antibodies against other P . aeruginosa antigens were detected . The highest IgA and IgG titer against alginate was induced by the subcutaneous immunization . IgA and IgG antibodies against other P . aeruginosa antigens developed in rats immunized with liver and sonicated bacteria . The highest IgA and IgG titers were obtained after intratracheal and subcutaneous immunization with sonicated bacteria . The present work has shown that IgA and IgG antibodies develop with high specificity after immunization . The different titers obtained do not necessarily reflect different degrees of protection. Gene, 1991 Dec 1, 108(1), 7 - 14 The broad-host-range plasmid pTF-FC2 requires a primase-like protein for autonomous replication in Escherichia coli; Dorrington RA et al.; A 3202-bp fragment of plasmid pTF-FC2, cloned into PUC19, had previously been identified as the minimum region required for replication in either Pseudomonas aeruginosa or Escherichia coli polA- mutants . During the course of experiments to construct broad-host-range cloning vectors based on the pTF-FC2 replicon, it was found that the 3202-bp fragment had an absolute requirement for some function of the pUC19 vector . This requirement was eliminated in the presence of co-resident pTF-FC2 derivatives . An additional 1239-bp fragment from pTF-FC2, immediately adjacent to the 3202-bp fragment, was identified which restored the ability of the pTF-FC2 replicon to replicate autonomously . Sequence analysis of the region revealed a single open reading frame encoding a 40-kDa polypeptide, which was synthesised in an in vitro transcription/translation system . A comparison of the amino acid sequence of this protein with sequence data banks revealed limited homology with the RepB' primase of the IncQ plasmid, RSF1010 . An M13 delta lac 110 replication-deficient phage system was used to demonstrate that the 40-kDa protein did function as a primase with respect to replication at the origin of replication (vegetative) of pTF-FC2. Gene, 1991 Dec 1, 108(1), 109 - 14 Pseudomonas aeruginosa plasmids as suicide vectors in Escherichia coli: resolution of genomic cointegrates through short regions of homology; Dunn IS; Pseudomonas aeruginosa plasmids which cannot replicate in Escherichia coli have been used to introduce specific modifications into the E . coli chromosome by homologous recombination ('gene targeting') . The E . coli gene (gpt) encoding guanine-xanthine phosphoribosyltransferase (Gpt) was used for initial targeting studies owing to the availability of a powerful positive selection for loss of the Gpt+ phenotype (6-thioguanine resistance or 6TGR or Gpt-) . P . aeruginosa plasmids containing selectable markers flanked by gpt sequences were introduced as supercoiled DNA into an E . coli strain which contained a normal gpt locus . Primary cointegration of such plasmids into the E . coli genome results in a gene duplication event which maintains Gpt function; a secondary recombinational event which resolves the cointegrate either reverses the primary event or results in replacement of the original gpt copy with the modified version . A 316-bp region of homology was sufficient for cointegrate formation, and resolution of the cointegrates through a shorter (92 bp) homologous flank was selectable through loss of Gpt function . The frequency of cointegrate resolution under these conditions was significantly above the spontaneous gpt mutational loss rate. J Clin Microbiol, 1991 Dec, 29(12), 2758 - 62 Ability of National Committee for Clinical Laboratory Standards-recommended quality control strains from the American Type Culture Collection to detect errors in disk diffusion susceptibility tests; Yechouron A et al.; The National Committee for Clinical Laboratory Standards (NCCLS) recommends, as a quality control for the disk diffusion susceptibility test, the use of three strains from the American Type Culture Collection: Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, and Escherichia coli ATCC 25922 . This study assesses the capacity of these strains to detect errors in the overall method . ATCC strains were tested by comparing testing by the standard NCCLS-recommended procedure (ST) with testing under the following conditions: incubation at 25 degrees C, Mueller-Hinton agar depths of 2 mm (AD2) and 8 mm (AD8), agar pHs of 6.5 and 8, inocula with McFarland standards of 0.25 (0.25M) and 4.0 McFarland (4.0M), direct inoculation without preincubation of inoculum (DI), and a 2-h delay between inoculation and disk application (2HR) . The frequency of zone measurements outside the NCCLS-recommended control zone limits were as follows: ST, 0%; AD2, 18%; AD8, 9.6%; pH 6.5, 7.9%; pH 8, 5.3%; 0.25M, 3.5%; 4.0M, 24%; DI, 3.4%; 2HR, 1.8%; 25 degrees C (only E . coli and P . aeruginosa were evaluable), 28% . These results suggest that the quality control strains are only partially effective in detecting single extreme laboratory errors and that careful laboratory supervision is necessary even in the setting of properly monitored quality control strains. EMBO J, 1991 Dec, 10(13), 4137 - 44 Mutations in TrpI binding site II that differentially affect activation of the trpBA promoter of Pseudomonas aeruginosa; Gao J et al.; In vitro, Pseudomonas aeruginosa TrpI protein activates transcription initiation at the trpBA promoter (trpPB) and represses initiation at its own promoter (trpPI), which diverges from, and overlaps, trpPB . Indoleglycerol phosphate (InGP) reduces the TrpI concentration required for binding to its strong binding site (site I), as measured by repression of trpPI; it also facilitates activation of trpPB, presumably because it enables TrpI to bind to a weaker binding site (site II) and thereby interact with RNA polymerase . The role of site II and InGP in regulation of the two promoters was investigated by constructing site II mutants . A 2 bp substitution affected the ability of TrpI to activate trpPB, but did not significantly affect TrpI binding to site II . A more extensive (8 bp) substitution inhibited TrpI-mediated activation of trpPB and TrpI-mediated protection of site II in a DNase I footprinting assay . However, the mutation did not alter the pattern of TrpI binding observed in gel retardation experiments . In particular, a more slowly-migrating complex (Complex 2) whose appearance was correlated with TrpI binding to site II was formed equally well on a wild-type or substituted DNA fragment . Based on the mutant phenotypes, we propose that a particular sequence of protein--protein and protein--DNA interactions is required for activation of trpPB by TrpI and InGP. Mayo Clin Proc, 1991 Dec, 66(12), 1249 - 59 The fluoroquinolones; Walker RC et al.; The fluoroquinolone class of antibiotics promises to become as diverse and as important as beta-lactam agents . The fluoroquinolones inhibit bacterial DNA gyrase and are bactericidal . All fluoroquinolones have potent activity against most gram-negative bacteria; ciprofloxacin is the most active against Pseudomonas aeruginosa . Activity against gram-positive organisms is variable; methicillin-resistant Staphylococcus aureus has acquired resistance to the fluoroquinolones at an alarming rate . Currently available quinolones do not have, but new quinolone agents likely will have, substantial activity against anaerobic bacteria . Some quinolones are also active against Mycobacterium, Chlamydia, and Mycoplasma organisms . All fluoroquinolones have excellent absorption after oral administration; however, this process can be impaired by the presence of aluminum- or magnesium-containing antacids and by zinc, iron, or calcium supplements . Ciprofloxacin is also available for intravenous use . Although most fluoroquinolones do not achieve adequate cerebros