G Batteriol Virol Immunol, 1983 Jul-Dec, 76(7-12), 239 - 45 {Comparative study of the in vitro activity of dibekacin, piperacillin, cefotaxime and cefuroxime on gram-negative bacteria}; Carlone NA et al.; The activity in vitro of the dibekacin was compared with that of piperacillin, cefotaxime and cefuroxime against 266 recently isolated gramnegative pathogens . Dibekacin was consistently more potent than cefotaxime, cefuroxime and piperacillin, with MIC50 and MIC90 values lower than the others . Dibekacin and cefotaxime were essentially similar in activity against all the bacteria, with the singular exception of Pseudomonas aeruginosa, which was markedly more susceptible to the former drug. FEBS Lett, 1983 Jun 27, 157(1), 46 - 50 A rapid stimulation of phosphatidylinositol metabolism in rabbit leukocytes by pseudomonal leukocidin; Hirayama T et al.; The time course experiments of 32Pi-labelling and breakdown of phospholipids in rabbit leukocytes exposed to leukocidin from Pseudomonas aeruginosa suggested that the initial action of this toxin was to stimulate phosphatidic acid production, presumably by causing a rapid metabolic change of phosphatidylinositol (PI response) correlating with phosphatidylinositol-specific phospholipase C and 1,2-diacylglycerol kinase . It appears that a rapid formation of phosphatidic acid and degradation of polyphosphoinositides in leukocytes treated with the toxin might be related a Ca2+-movement from extra- and intracellular spaces, resulting in the activation of Ca2+-dependent enzymes involved in the leukocidic process. Biochem Biophys Res Commun, 1983 Jun 15, 113(2), 526 - 30 Comparative studies of monohemic bacterial C-type cytochromes . Redox and optical properties of Desulfovibrio desulfuricans Norway cytochrome C553(550) and Pseudomonas aeruginosa cytochrome C551; Bianco P et al.; Redox properties of cytochrome c553(550) from Desulfovibrio desulfuricans Norway (Eo' = 0.04 + 0.02 V/NHE) and cytochrome c551 from P . aeruginosa (Eo = 0.25 +/- 0.02 V/NHE) are compared with those of some monohemic c-type cytochromes . The pK value for the equilibrium between the pH-dependent forms of cytochrome c553(550) (pK = 10.3 +/- 0.1) has been also determined . It is to be noted that the difference between redox potentials can extend to nearly 250 mV, though the axial heme ligands are identical . Structural reasons have to be invoked to explain these variations. Lancet, 1983 Jun 11, 1(8337), 1318 - 20 Nosocomial bacterial eye infections in intensive-care units; Hilton E et al.; A cluster of ten nosocomial eye infections occurred in three intensive-care units during an 18-month period . Nine of the ten patients were intubated, all were obtunded, and all had copious sputum production . The bacteria isolated from the patients' sputum samples and from the eyes were identical in nine cases . Pseudomonas aeruginosa caused six of the infections, including all those with complications (three corneal ulcers, two hypopyon, one opaque cornea, two corneal rupture) . Three patients lost their sight . Only the left eye was infected in nine cases . In a prospective study of bacterial dispersion during tracheal suctioning of twenty intubated patients, patients with copious secretions had significantly higher bacterial colony counts on settle plates than those without . Colony counts were higher on the side opposite to the hand the nurse used to withdraw the catheter than on the same side . Nurses tended to withdraw the catheter diagonally across the patient's face, which may explain the selective involvement of the left eye. Laryngol Rhinol Otol (Stuttg), 1983 Jun, 62(6), 276 - 9 {Malignant otitis externa}; Koch U; Malignant otitis externa represents a special form of inflammatory alteration of the external ear . The inflammation can spread to surrounding bones (temporal bone, skull base - to the foramen magnum), as well as to neighbouring tissue, such as the parotid gland, the temporo-mandibular joint and soft tissue near the skull base . Most patients are elderly, latent or manifest diabetics . The causative organism was always proved to be Pseudomonas aeruginosa . The disease is called "malignant" because of its high mortality rate . Decreasing this mortality is possible - as demonstrated in 6 patients - via early diagnosis, sufficient surgery, as well as local and systemic antibiotics. Am J Vet Res, 1983 Jun, 44(6), 1135 - 40 Experimental Pseudomonas aeruginosa ulcerative keratitis model in the dog; Wyman M et al.; Primary Pseudomonas aeruginosa ulcerative keratitis and accompanying secondary ocular disease were induced bilaterally in 12 of 12 dogs subjected to corneal trephination and intrastromal inoculation . Successful experimental infection was based on recovery of viable Pseudomonas organisms from the lesions, as well as gross and biomicroscopic appearance of the corneas. J Lab Clin Med, 1983 Jun, 101(6), 940 - 54 DNA hybridization studies of the association of Pseudomonas maltophilia with inflammatory bowel diseases; Graham DY et al.; An infectious etiology has been suggested for the inflammatory bowel diseases, Crohn's disease and ulcerative colitis, and an association of cell wall-defective variants of Pseudomonas maltophilia and Pseudomonas-like group Va bacteria with Crohn's disease has been reported by Parent and Mitchell . Seven of the Parent-Mitchell isolates were compared by using DNA hybridization and six were identical and similar, but not identical, to a type strain of P . maltophilia . The seventh isolate showed extensive homology with VARC, a reference strain of group Va organism, but not with P . maltophilia . Pseudomonas DNAs were radiolabeled by nick translation and used as probes for homologous DNA in hybridization experiments involving 48 different tissues . The presence of DNA with sequences homologous to those of P . maltophilia was detected in three of 23 Crohn's disease samples, two of 10 ulcerative colitis samples, and none of 15 control samples . There was no hybridization with VARC or Pseudomonas aeruginosa probes . We were unable to culture cell wall-defective organisms from patients' tissues but have detected pleomorphic organisms in hypertonic cultures of 14 of 53 Crohn's disease specimens, none of six ulcerative colitis specimens, and none of 11 control specimens . None reverted to normal bacteria . These results do not support an exclusive association of P . maltophilia with Crohn's disease but rather suggest a possible association of P . maltophilia with IBD . Technical limitations currently preclude definitive conclusions regarding the significance of this association . Although we demonstrated the presence of DNA sequences with homology to P . maltophilia DNA in tissues of some patients with IBD, the role, if any, of these bacteria in the pathogenesis of IBD has yet to be established. Antimicrob Agents Chemother, 1983 Jun, 23(6), 874 - 80 Effects of AC-1370, a new semisynthetic cephalosporin, on phagocyte functions; Ohnishi H et al.; The effects of a new semisynthetic cephalosporin, AC-1370, on phagocyte functions were compared with those of cefoperazone . AC-1370 augmented phagocytosis by mouse macrophages in vitro and in vivo, by mouse neutrophils in vivo, and by human neutrophils in vitro . Cefoperazone suppressed phagocytosis by mouse macrophages and neutrophils . Random migration and chemotaxis of mouse and human neutrophils were increased by the addition of AC-1370 . Nitroblue tetrazolium reduction by human neutrophils was enhanced by the addition of AC-1370 . Intracellular killing of bacteria by macrophages was also enhanced by AC-1370 . Further, bactericidal effects of AC-1370 against Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumoniae were augmented when they were each cultured with mouse or human leukocytes . These results suggest that AC-1370 is an unique beta-lactam antibiotic which has a potentiating effect on phagocyte functions as well as a bactericidal effect. Diagn Microbiol Infect Dis, 1983 Jun, 1(2), 159 - 62 Morphologic aberration associated with colonial tenacity of Pseudomonas aeruginosa; Bottone EJ et al.; A blood isolate of Pseudomonas aeruginosa was encountered which produced, on subculture to Mueller-Hinton agar, markedly adherent, tenacious colonies which were characterized microscopically by the presence of serpentine rows of interlocking bacilli . Factors accounting for the observed morphologic aberration, which was lost upon subculture, remain unknown. Zh Mikrobiol Epidemiol Immunobiol, 1983 Jun, (6), 72 - 7 {Protective cross activity of the extracellular mucus of Pseudomonas aeruginosa}; Stanislavskii ES et al.; Extracellular slime was isolated from 15 P . aeruginosa typing strains of different O-serotypes (immunotypes) . The isolated slime, partially purified by ethanol precipitation, was later referred to as crude slime . Glycolipoprotein was obtained from crude slime and lipopolysaccharide (LPS) was obtained from acetone-dried microbial cells by the method of aqueous-phenol extraction . All these antigenic preparations were studied in the active mouse cross-protection tests: immunized mice were challenged with 7 strains of different immunotypes, strain No . 170 019 or toxigenic strain PA-103 . In experiments on mice the slime of different P . aeruginosa serotypes (immunotypes) was found to stimulate immunity to intraperitoneal infection with P . aeruginosa, both homologous or heterologous in respect to their immunotype, including toxigenic strains . Slime glycoprotein also stimulated active cross-immunity in mice, but the level of this immunity was higher than that of immunity stimulated by crude slime . LPS showed mostly weak protective activity in experiments on mice. Zh Mikrobiol Epidemiol Immunobiol, 1983 Jun, (6), 69 - 72 {The effect of Pseudomonas aeruginosa exotoxin on various nonspecific factors of immunologic reactivity in an experiment}; Dziubak ST; The main characteristics of the nonspecific responsiveness of the body have been studied on the model of acute P . aeruginosa intoxication . An increase in phagocytic and lysozyme activity and in the bactericidal properties of blood serum have been shown to occur during the first 6 hours after the introduction of P . aeruginosa exotoxin . The titer of complement and beta-lysin activity decrease . At a later period of observations a sharp drop in all the characteristics under study (except lysozyme activity) occurs. Zh Mikrobiol Epidemiol Immunobiol, 1983 Jun, (6), 100 - 3 {Antibodies against Pseudomonas aeruginosa toxin in preparations of normal human immunoglobulin}; Ianishevskaia MN et al.; Some lots of commercial normal human immunoglobulin have been found to contain antibodies neutralizing the action of P . aeruginosa exotoxin . The content of antibodies in human immunoglobulin preparations correlates to a certain degree with their protective activity determined in the passive protection test in white mice . Certain lots of normal human immunoglobulin have been found to possess protective activity, but contain no specific antitoxins . The clinical testing of these immunoglobulin preparations used for treating patients with Pseudomonas infections has yielded promising results. J Antimicrob Chemother, 1983 Jun, 11(6), 511 - 5 In-vitro susceptibility of Pseudomonas aeruginosa to old and new beta-lactam antibiotics and aminoglycosides; Van der Auwera P et al.; In-vitro, activities of gentamicin, tobramycin, netilmicin, amikacin, cefsulodin, latamoxef (moxalactam), carbenicillin, ticarcillin and piperacillin were compared against 147 randomly selected strains of Pseudomonas aeruginosa . Tobramycin was the most active aminoglycoside (MIC 90:4 mg/l), complete cross resistance with gentamicin (MIC 90:8 mg/l) was observed . Amikacin was the best alternative aminoglycoside (MIC 90:12 mg/l) Netilmicin showed only moderate activity (MIC 90:16 mg/l) . Cefsulodin was the most active beta-lactam antibiotic (MIC 90:8 mg/l) but significant cross-resistance was observed with ticarcillin (MIC 90:32 mg/l) and piperacillin (MIC 90:12 micrograms/ml) . Carbenicillin was two dilutions less active than ticarcillin, latamoxef showed a good activity (MIC 90:64 mg/l) . Having the highest ratio between serum achievable concentration and MIC 90, piperacillin could be the best alternative drug to the aminoglycosides, of the tested antibiotics. Can J Microbiol, 1983 Jun, 29(6), 732 - 3 FP2 plasmid curing in Pseudomonas aeruginosa; Potter AA et al.; A procedure for the elimination of the IncP-8 plasmid FP2 from Pseudomonas aeruginosa strain 1 was developed . The procedure consists of freezing cells, competent for transformation, in 15% glycerol at -70 degrees C for at least 48 h and screening survivors for loss of mercuric chloride resistance . Curing frequencies of 0.5% were achieved only in host cells carrying a dht mutation (unable to convert thymine to dihydrothymine). Can J Microbiol, 1983 Jun, 29(6), 700 - 3 Competitive adherence as a mechanism of bacterial interference; Bibel DJ et al.; To determine whether competition among bacteria for specific attachment sites on host cells can explain bacterial interference, Staphylococcus aureus strain 502A was tested in turn against two different nasal coryneforms, a strain of Pseudomonas aeruginosa, and a virulent strain of S . aureus, all in the presence of nasal mucosal cells . Particularly examined was the influence of sequence in which bacteria were presented to the nasal cells in comparison with initial mixtures and individual suspensions . Results paralleled those observed in clinical prophylaxis: the bacterium first to adhere to the epithelial cells was able, under uniform conditions, to interfere with the colonization of subsequently added bacteria . Secondary adherence was not eliminated but substantially reduced, and was probably related to steric blockage by the initial colonizer and its particular ability to dissociate from the host cell. Pathol Biol (Paris), 1983 Jun, 31(6), 471 - 5 {Sensitivity of Pseudomonas aeruginosa to beta-lactam antibiotics and effects of beta-lactamases}; Avril JL et al.; The activities of carbenicillin, ticarcillin, piperacillin, cefsulodin, ceftriaxone, azlocillin, ceftazidime and apalcillin were evaluated against 128 hospital isolates of Pseudomonas aeruginosa . Against the 85 isolates that were susceptible to carbenicillin, apalcillin had the best minimal inhibitory concentrations, the median MIC being 1, 1 microgram/ml . Against the 43 isolates resistant to carbenicillin, ceftazidime inhibited 90% of organisms at a concentration of 16 micrograms/ml . A constitutive beta-lactamase, was found in 27 of the 43 resistant isolates . All the 128 isolates, but one, were producers of an inducers of an inducible beta-lactamase . Ceftriaxone, piperacillin and azlocillin were highly antagonized by cefoxitin . The extent of antagonism was lower with ticarcillin and carbenicillin. J Clin Microbiol, 1983 Jun, 17(6), 1054 - 6 4-h Identification of Pseudomonas aeruginosa with 9-chloro-9-(4-diethylaminophenyl)-10-phenylacridan; Davis JR et al.; A total of 361 gram-negative bacilli were evaluated for their ability to grow in the presence of 9-chloro-9-(4-diethylaminophenyl)-10-phenylacridan . The minimum time required for the production of visual turbidity in brain heart infusion broth was determined to be 4 h in shake cultures at 35 degrees C . The minimal inhibitory concentration (MIC) of 9-chloro-9-(4-diethylaminophenyl)-10-phenylacridan in brain heart infusion broth was determined for 174 isolates . The MICs for all 40 Pseudomonas aeruginosa isolates tested were greater than 50 micrograms/ml . The MICs for the other 53 pseudomonads tested were less than or equal to 5 micrograms/ml . Among 81 other gram-negative bacilli tested, the MICs for 4 were 15 micrograms/ml, the MICs for 15 were 10 micrograms/ml, the MICs for 21 were 5 micrograms/ml, and the MICs for 41 were less than or equal to 1 micrograms/ml . Based on these data, 361 gram-negative bacilli were inoculated into brain heart infusion broth containing 15 micrograms of 9-chloro-9-(4-diethylaminophenyl)-10-phenylacridan per ml and incubated on a shaker for 4 h . The only bacteria that produced visual turbidity were identified as P . aeruginosa (170 of 170 isolates). Am J Hosp Pharm, 1983 Jun, 40(6), 998 - 1001 Growth of bacteria in intravenous fluids under stimulated actual-use conditions; Hugbo PG et al.; The growth of microorganisms in nonnutritive intravenous solutions under simulated actual-use conditions was studied . Small quantities of Pseudomonas aeruginosa, Staphylococcus aureus, and Klebsiella pneumoniae (final concentration 200-400 cells/ml) were injected into 500-ml containers (glass bottles and plastic bags) of 5% dextrose injection, 0.9% sodium chloride injection, and 5% dextrose and 0.9% sodium chloride injection . Additives (ampicillin, vitamin K, lidocaine, and vitamin B complex) were included in some i.v . solutions . Administration sets were attached to the i.v . containers, and the solutions were run into collection bottles; samples were withdrawn at 0, 1, 2, 3, 4, 5, 6, and 8 hours after contamination and plated for viable counts . Staph . aureus and K . pneumoniae remained viable in 5% dextrose injection and in 0.9% sodium chloride injection, but the numbers of these bacteria did not increase . The number of Ps . aeruginosa declined in all three solutions . In 5% dextrose and 0.9% sodium chloride injection, the number of K . pneumoniae declined but Staph . aureus maintained viability . The type of container and the drug additives had no effect on microbial growth, except that ampicillin was bactericidal to Staph . aureus . Low-level contamination of these bacteria in nonnutritive i.v . solutions under actual-use conditions does not result in large numbers of organisms within the time frame in which most solutions are administered. J Trauma, 1983 Jun, 23(6), 530 - 4 Anti-Pseudomonas aeruginosa activity of an intravenous human IgG preparation in burned mice; Collins MS et al.; A commercially available human IgG chemically modified for intravenous infusion (IGIV) was tested in burned mice for activity against eight strains of Pseudomonas aeruginosa . An 8.7 to 9.6% full-thickness burn was made with a gas flame on the shaved backs of anesthetized mice . A suspension of P . aeruginosa in 0.5 ml saline was then injected subcutaneously in the burn site . Inocula included seven American Type Culture Collection reference strains representing the seven Fisher-Devlin-Gnabasik immunotypes plus an additional strain of immunotype 1 . IGIV immunotherapy did not significantly reduce mortality in burned mice challenged with immunotypes 5 and 6 but was highly protective against immunotypes 1-4 and 7 . Groups of mice challenged with these five types and treated with approximately 100 or 400 mg IGIV/kg body weight had cumulative mortality rates at 15 days ranging from 0 to 30%, versus an overall mean 84.3% mortality in human serum-albumin treated controls . IGIV was protective if given up to 12 hours after challenge . These data indicate that IGIV has significant in vivo activity against P . aeruginosa and suggest that IGIV immunotherapy may be of value in the treatment of major thermal trauma in man. J Hyg (Lond), 1983 Jun, 90(3), 489 - 98 Otitis externa by Pseudomonas aeruginosa associated with whirlpools; Havelaar AH et al.; Over a period of about 1 year, otitis externa occurred in at least 300 visitors to a recreational park . The infections were associated with the presence of Pseudomonas aeruginosa in insufficiently chlorinated whirlpools. Am J Med, 1983 Jun, 74(6), 980 - 7 Clinical significance of serum antibody responses to exotoxin A and type-specific lipopolysaccharides in patients with Pseudomonas aeruginosa infections; Pollack M et al.; Serum antibodies to Pseudomonas aeruginosa exotoxin A and immunotype-specific lipopolysaccharides were evaluated as diagnostic and prognostic markers in patients with Pseudomonas disease . Hemagglutination titers to exotoxin A were 1:1,024 or higher and/or showed a fourfold acute-to-convalescent increase in 17 of 25 (68 percent) patients infected with Pseudomonas compared with only one of seven (15 percent) colonized (p = 0.01) and two of 24 (8 percent) culture-negative patients (p less than 0.001) . By comparison, hemagglutination titers to the lipopolysaccharide of patients' Pseudomonas isolates were 1:1,024 or higher or showed a fourfold increase in only four of 17 (24 percent) infected patients and in none of six (0 percent) colonized patients (p = 0.96) . Serial antibody titers to exotoxin A provided serologic confirmation of invasive disease, distinguished infection from colonization, and, in the case of decreasing titers, indicated successful therapy . It is concluded that serum antibodies to exotoxin A are useful serologic markers for the clinical assessment of Pseudomonas infections in man. J Lab Clin Med, 1983 Jun, 101(6), 896 - 902 Ticarcillin-tobramycin-rifampin: in vitro synergy of the triplet combination against Pseudomonas aeruginosa; Zuravleff JJ et al.; MICs of ticarcillin, tobramycin, and rifampin alone and in combination were determined by a three-dimensional checkerboard method for 33 isolates of Pseudomonas aeruginosa . Twenty-nine of 33 isolates were affected synergistically (FIC index less than 1.0) by the combination of ticarcillin-tobramycin, including 13 of the 16 isolates resistant to ticarcillin and/or tobramycin alone . However, despite fulfilling the criteria for synergy, the MIC of the ticarcillin and/or tobramycin when in combination still exceeded attainable serum concentrations for 12 of the 13 resistant isolates . When rifampin was added to ticarcillin-tobramycin, a synergistic interaction was observed for all 33 isolates . Furthermore, of the 16 isolates resistant to ticarcillin and/or tobramycin, eight were inhibited by attainable concentrations of all three antibiotics in combination . If these results can be confirmed in the clinical situation, application of the three-drug combination of ticarcillin-tobramycin-rifampin might improve survival in selected patients with serious P . aeruginosa infections. J Infect Dis, 1983 Jun, 147(6), 1090 - 8 Antibody activity against Pseudomonas aeruginosa in immune globulins prepared for intravenous use in humans; Pollack M; Twenty-seven lots of human immune globulin for intravenous use (IGIV) from seven different producers, including one hyperimmune preparation, were examined for immunologic reactivity and opsonic and protective activity against Pseudomonas aeruginosa . All IGIVs contained hemagglutinating antibodies to seven immunotype-specific lipopolysaccharides of P . aeruginosa (geometric mean titer +/- SE, 14 +/- 3 for nonhyperimmune preparations and 420 for the hyperimmune product) and to exotoxin A (77 +/- 15) . All IGIVs tested demonstrated opsonic activity against P . aeruginosa in an in vitro granulocyte-dependent bactericidal assay . All IGIVs conferred dose-dependent protection (hyperimmune more so than nonhyperimmune) against fatal burn-wound infections due to P . aeruginosa in mice . In contrast, single lots of hyperimmune and nonhyperimmune IGIV conferred limited protection against infections due to P . aeruginosa in granulocytopenic mice . These studies indicate the potential prophylactic efficacy of IGIV in human pseudomonas disease, and the possible need for high doses of hyperimmune IGIV in granulocytopenic patients. Eur J Biochem, 1983 Jun 1, 133(1), 119 - 25 Purification and properties of 2-aminoethylphosphonate:pyruvate aminotransferase from Pseudomonas aeruginosa; Dumora C et al.; 2-Aminoethylphosphonate aminotransferase has been purified to homogeneity with a yield of 15% from cell extracts of Pseudomonas aeruginosa . The molecular weight of the enzyme was estimated by gel filtration to be 65000 +/- 2000 . Sodium dodecyl sulfate/polyacrylamide gel electrophoresis yielded a molecular weight of 16500 +/- 1000, suggesting a tetrameric model for this protein . The absorption spectrum exhibits maxima at 280 nm, 335 nm and 415 nm which are characteristic of a pyridoxal-phosphate-dependent enzyme: 4 mol of pyridoxal 5'-phosphate/mol of enzyme have been found . This aminotransferase catalyzes the transfer of the amino group of 2-aminoethylphosphonate (ciliatine) to pyruvate to give 2-phosphonoacetaldehyde and alanine . A pH optimum between 8.5-9 and an activity increasing from 30 degrees C to 50 degrees C have been observed . The reaction follows Michaelis-Menten kinetics with Km values of 3.85 mM and 3.5 mM for ciliatine and pyruvate respectively . This enzyme shows a very high specificity since ciliatine and pyruvate are the only amino donor and acceptor respectively . Methyl, ethyl and propylphosphonic acids are better competitors towards ciliatine than their alpha-amino derivatives . 3-Aminopropylphosphonate, the higher homologue of ciliatine, is recognized neither as a substrate nor as an inhibitor . The enzyme activity is significantly affected by carbonyl reagents and by HgCl2 . Transamination of 2-aminoethylphosphonate is the first step of a double-step pathway which leads to the cleavage of its C-P bond. Ann Ophthalmol, 1983 Jun, 15(6), 559 - 61 Successful management of Pseudomonas endogenous endophthalmitis; Cowan CL Jr et al.; A 38-year-old man acquired a Pseudomonas aeruginosa wound infection after transplant nephrectomy . After an initial response to therapy, Pseudomonas sepsis developed, and he was readmitted to the hospital . Two days after admission, blurred vision developed . Ocular examination revealed a severe vitritis and exudate in the pupillary space on the right side . Endogenous endophthalmitis was suspected, and a diagnostic vitreous aspiration yielded P aeruginosa on culture . The patient was treated with intravitreal, subconjunctival, and topical antibiotics as well as periocular steroids, and was able to achieve useful vision before his death from his systemic illness. J Clin Microbiol, 1983 Jun, 17(6), 1032 - 8 Quality control of moxalactam susceptibility disks; Barry AL et al.; In vitro evaluation of two types of moxalactam disks revealed significant performance differences when Staphylococcus aureus was being tested . The differences were traced to the amount of decarboxylated moxalactam present in the disks . The decarboxylated analog was much more active than the parent compound against S . aureus, not active against Pseudomonas aeruginosa, and approximately as active as the parent compound against Escherichia coli . A nine-laboratory coordinated study was performed to establish quality control parameters for 30-micrograms moxalactam disks . Problems with the establishment of interpretive standards for moxalactam disk tests were evaluated in the light of differences between disks utilized in earlier studies and those that are now commercially available . The type of disk greatly influences standards for tests with S . aureus but has insignificant influence on testing gram-negative bacilli. Antonie Van Leeuwenhoek, 1983 Jun, 49(2), 173 - 82 Protective activities of ribosomal ribonucleic acid and lipopolysaccharide of Pseudomonas aeruginosa: a comparative study; Gonggrijp R et al.; Ribosomal ribonucleic acid (RNA) and lipopolysaccharide (LPS) from P . aeruginosa were compared with respect to their protective activities in mice against an infection with P . aeruginosa . This study is concentrated on the protective activity of RNA . RNA isolated from purified ribosomes did not contain LPS as determined with the Limulus test . Injection of RNA with the adjuvant dimethyldioctadecylammonium bromide (DDA) protected mice against P . aeruginosa without inducing LPS-specific antibodies . C3H/HeJ mice which are relatively insensitive to the protective activity of LPS could be protected with RNA . The protective activities of RNA and LPS from a mutant strain of P . aeruginosa, PAC 605, containing defective lipopolysaccharide, were compared with the protective activities of RNA and LPS from the parent strain, PAC IR . The protective activity of LPS from PAC 605 was 1000 fold lower than the protective activity of LPS from PAC IR . RNA preparations of both strains induced similar percentages of survival . The protective activity of ribosomal RNA from P . aeruginosa was nonspecific since mice were also protected against a heterologous serotype of P . aeruginosa and against Escherichia coli . RNA from ribosomes of P . aeruginosa, E . coli and the non-lipopolysaccharide containing Saccharomyces cerevisiae had similar protective activities . No protection was obtained with the ribonucleic acid from the E . coli phage MS2 . It is concluded that ribosomal RNA has protective activities distinct from those of LPS. FEBS Lett, 1983 May 30, 156(1), 113 - 8 The motile and tactic behaviour of Pseudomonas aeruginosa in anaerobic environments; Armitage JP et al.; ATP generated by the anaerobic metabolism of L-arginine in Pseudomonas aeruginosa was used to maintain the membrane potential . Although both the ATP concentration and membrane potential were lower than in aerobically incubated bacteria, motility and chemotaxis were almost normal . Venturicidin stopped anaerobic motility by abolishing the membrane potential . The addition of venturicidin to aerobic bacteria caused an increase in the membrane potential, but a decrease in internal ATP concentration, resulting in bacteria which were motile but non-chemotactic . The membrane potential was the only requirement for continued motility but ATP was required in addition for chemotaxis. J Biol Chem, 1983 May 25, 258(10), 6405 - 9 Interaction of cytochrome c with the blue copper proteins, plastocyanin and azurin; Augustin MA et al.; Bimolecular rate constants have been determined for the reactions of native horse cytochrome c, eight 4-carboxy-2,6-dinitrophenyl (CDNP-) cytochromes c singly modified at lysines 7, 13, 25, 27, 60, 72, 86, or 87 and one 2,3,6-trinitrophenyl cytochrome c singly modified at lysine 13, with the blue copper proteins, plastocyanin (from parsley leaves) and azurin (from Pseudomonas aeruginosa) . Plastocyanin, a protein having a negative charge of about -7, yields a bimolecular rate constant with native ferrocytochrome c of 1.5 x 10(6) M-1 S-1, which decreases with the modified cytochromes c to a minimum of 7.5 x 10(5) M-1 S-1 for the CDNP-lysine 13 derivative . Conversely azurin, a protein with an overall negative charge of only about -1 to -2, exhibits bimolecular rate constants with native ferrocytochrome c of 6.6 x 10(3) M-1 S-1 at pH 6.1 and 4.0 x 10(3) M-1 S-1 at pH 8.6, which increase upon modification of the cytochrome c to a maximum of 4.1 x 10(4) M-1 S-1 at pH 6.1 and 2.7 x 10(4) M-1 S-1 at pH 8.6, for the CDNP-cytochrome c modified at lysine 72 . This behavior indicates that: 1) the reaction of cytochrome c occurs at a negatively charged site on plastocyanin, whereas azurin behaves as a positively charged reactant, the electrostatics governing to a large extent the relative reactivities of the modified cytochromes c; 2) in both cases the interaction domain on cytochrome c is located on the "front" surface of the protein and encompasses the solvent accessible edge of the heme prosthetic group, as is the case for all the reactions of cytochrome c with its mitochondrial protein redox partners, as well as for small inorganic redox complexes; and 3) the bimolecular rate constants for plastocyanin and azurin are orders of magnitude slower and the effects of lysine modifications far smaller than for the reactions with physiological systems, indicating that: (a) the electric fields generated by the reactants do not align them, prior to electron transfer, as effectively as for the physiological reaction partners of cytochrome c; and (b) there is an absence of a precise molecular fit between cytochrome c and the nonphysiological redox partners. Antimicrob Agents Chemother, 1983 May, 23(5), 766 - 73 In vitro study of bacterial growth inhibition in concentrated sugar solutions: microbiological basis for the use of sugar in treating infected wounds; Chirife J et al.; The use of sugar for the treatment of infected wounds was investigated in in vitro experiments with bacteria pathogenic to humans, such as Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Staphylococcus aureus . Studies showed that solutions of appropriate sugar concentration incubated at pH 7.0 and 35 degrees C were lethal to the bacterial species studied . On the basis of these results, it is proposed that an important function of sugar in the treatment of infected wounds is to create an environment of low water activity (aw), which inhibits or stresses bacterial growth. J Clin Microbiol, 1983 May, 17(5), 864 - 9 Microbiological and clinical evaluation of the isolator lysis-centrifugation blood culture tube; Henry NK et al.; In a controlled evaluation of 6,010 blood cultures, the yield of clinically significant microorganisms was greater from a lysis-centrifugation system (Isolator, Du Pont Co.) than from a nonvented vacuum bottle containing tryptic soy broth with sodium polyanetholesulfonate and CO2 and a vented bottle containing biphasic brain heart infusion medium with sodium polyanetholesulfonate . The Isolator significantly increased the frequency of isolation of Staphylococcus aureus and Candida spp . and significantly decreased the time required for the detection of S . aureus, Pseudomonas aeruginosa, and Candida spp.; however, anaerobic bacteria were recovered significantly more frequently from nonvented bottles with tryptic soy broth, and pneumococci were recovered significantly more frequently from both bottle systems . Contamination of cultures was significantly greater with the Isolator system than with either bottle system . Regardless of the number of blood cultures obtained per septic episode, the Isolator detected microbiologically proven bacteremia or fungemia in a significantly greater number of patients and significantly decreased the time required for detection. J Infect Dis, 1983 May, 147(5), 918 - 32 Once-daily vs . continuous aminoglycoside dosing: efficacy and toxicity in animal and clinical studies of gentamicin, netilmicin, and tobramycin; Powell SH et al.; The dosing frequency of aminoglycoside antibiotics may alter efficacy and toxicity independent of total daily dose . Once-daily tobramycin dosing was compared with continuous infusion in three models of efficacy . Acute pneumonia due to Pseudomonas aeruginosa in guinea pigs responded better to once-daily dosing, and chronic pneumonia in rats and endocarditis in rabbits responded equally to both regimens . Dogs given gentamicin, tobramycin, or netilmicin once daily, with maximum serum concentrations of greater than 100 mg/liter, had less nephrotoxicity than dogs given continuous infusions . Tobramycin was given once daily or continuously to 52 patients with cystic fibrosis who in 10 days had no change in creatinine clearance or hearing despite maximum serum tobramycin concentrations of 40 mg/liter . Intermittent dosing of aminoglycosides, causing infrequent large maximum serum concentrations, may be less toxic and equally efficacious as frequent dosing. J Infect Dis, 1983 May, 147(5), 910 - 7 Impact of dosing intervals on activity of gentamicin and ticarcillin against Pseudomonas aeruginosa in granulocytopenic mice; Gerber AU et al.; The influence of dosing intervals on the activity of gentamicin and ticarcillin against Pseudomonas aeruginosa was studied in vivo . Granulocytopenic mice infected with P . aeruginosa in the thigh muscle were treated with 1-hr or 3-hr injections of gentamicin, ticarcillin, or gentamicin-ticarcillin . Plasma pharmacokinetics of the drugs were correlated with antibacterial activity . Gentamicin injected every 1 hr tended to be less active than gentamicin injected at longer intervals . In contrast, ticarcillin given every 1 hr was significantly more efficacious than equivalent total doses injected every 3 hr . The dosing schedule of gentamicin-ticarcillin was again important for ticarcillin but did not appreciably affect the antibacterial activity of gentamicin . Thus, antimicrobial chemotherapy of P . aeruginosa infections in the granulocytopenic host might be improved by administering ticarcillin rather than gentamicin as a constant infusion. J Antimicrob Chemother, 1983 May, 11 Suppl B, 175 - 81 Comparative clinical evaluation of azlocillin and gentamicin; Sabbaj J et al.; Forty-four patients with severe systemic bacterial infection were treated with azlocillin (20) or gentamicin (24) . The commonest sites of infection were skin and soft tissue, lungs and bone . Thirty-eight patients had received previous antimicrobial therapy . The commonest infecting organism was Pseudomonas aeruginosa . The overall response rate in the azlocillin group was cure or partial cure in 18 patients and failure in one patient, and in the gentamicin group 15 cures or partial cures and six failures . Four patients, one on azlocillin and three on gentamicin, could not be evaluated . Azlocillin was an effective and safe therapy for the treatment of Ps . aeruginosa infections. Infect Immun, 1983 May, 40(2), 659 - 64 Passive protection against Pseudomonas aeruginosa infection in an experimental leukopenic mouse model; Cryz SJ Jr et al.; An experimental leukopenic mouse model was used to evaluate the protective capacities of immunoglobulin G (IgG) fractions directed against toxin A (AT-IgG), elastase (AE-IgG), and lipopolysaccharide (ALPS-IgG) against fatal Pseudomonas aeruginosa infection . Statistically significant protection, as measured by long-term survival, was observed only when mice were treated with serotype-specific ALPS-IgG . The mean lethal dose for P . aeruginosa could be increased by as much as 6,600-fold for mice given ALPS-IgG as compared to mice which received only normal rabbit IgG . ALPS-IgG afforded high levels of protection, even when administered up to 6 h postchallenge . Experiments designed to monitor the growth and spread of a locally administered challenge showed that ALPS-IgG prevented bacteremia and organ colonization, which were pronounced in control animals . The effectiveness of combined antibiotic and immune therapy was tested . Gentamicin alone or in combination with AT-IgG or AE-IgG provided no detectable protection . However, its use with ALPS-IgG afforded substantially higher levels of protection than ALPS-IgG alone. Ann Microbiol (Paris), 1983 May-Jun, 134A(3), 281 - 94 A complement-sensitive mutant of Pseudomonas aeruginosa; Offredo-Hemmer C et al.; The role of complement in the bactericidal activity of human serum against a mutant strain of Pseudomonas aeruginosa used as a model was demonstrated . The involvement of complement in the bacterial destruction of P . aeruginosa, and the contribution of the alternative and classical pathways of the complement system were directly evidenced by using sera from complement-deficient patients. Ann Microbiol (Paris), 1983 May-Jun, 134A(3), 255 - 66 {Utilization of various omega-guanidoalkylphosphonic acids by Pseudomonas aeruginosa}; de Tinguy-Moreaud E et al.; Bacterial growth was studied in synthetic media containing guanidomethyl-, 2-guanidoethyl-, 3-guanidopropyl- or 4-guanido-1-aminobutyl-phosphonic acid, as a possible nitrogen or phosphorus source . Among these four compounds, 2-guanidoethylphosphonic acid (2-GEPh) appeared to be the only efficient nitrogen nutrient . Our results are discussed in light of recent data on Pseudomonas aeruginosa amidinohydrolases . In addition, 2-GEPh proved to be a valuable source of phosphorus; the phosphorus group of its higher homologue 3-guanidopropylphosphonic acid was also used, but the linear bacterial growth curve reflected a limited rate of phosphate release . The characterization of ethylguanidine and propylguanidine in the corresponding culture filtrates suggests a hydrolytic process similar to that described for 3-aminopropylphosphonic acid. Pathol Biol (Paris), 1983 May, 31(5), 387 - 91 {Pseudomonas aeruginosa: acquired in vitro resistance to beta-lactams}; Thabaut A et al.; The development of resistance acquired in vitro to 5 semi-synthetic penicillins: carbenicillin, ticarcillin, azlocillin, mezlocillin, piperacillin and to 5 cephalosporins: cefotaxime, cefoperazone, moxalactam, cefsulodin and ceftazidime, was compared in 6 strains of Pseudomonas aeruginosa . The strains were selected on the basis of their phenotypic resistance: 3 were susceptible to all the betalactam antibiotics tested, 1 was resistant to carbenicillin and ticarcillin but remained susceptible to the others, 2 were susceptible to cefsulodin and ceftazidime but resistant to the others . The development of resistance was investigated by subsequent passages in liquid medium: up to 15 passages or up to an MIC of 4 096 mg/l for a penicillin or 512 mg/l for the cephalosporins . Irrespectively of the phenotypic resistance, for all cephalosorins the MIC became greater than or equal to 64 mg/l and very often greater than or equal to 512 mg/l after 1 to 3 passages . For the penicillin susceptible strains very high MICs were obtained more rapidly with azlocillin and piperacillin (1-2 passages) than with carbenicillin or ticarcillin (5-9 passages) . These results are not in favour of a monotherapy with betalactam antibiotics, especially cephalosporins, in the treatment of Pseudomonas aeruginosa infections, but suggest the preferential use of carbenicillin and especially ticarcillin for sensitive isolates. Pathol Biol (Paris), 1983 May, 31(5), 383 - 6 {Comparative bactericidal activity of cefsulodin and ceftazidime on Pseudomonas aeruginosa}; Delisle-Mizon F et al.; This research concerns the bacteriostatic and the bactericidal activity of two beta-lactams (cefsulodin and ceftazidime) on ten strains of Pseudomonas aeruginosa affected by carbenicillin . Additionally to classical approaches in the broth and agar technics, a method of culture on filter membrane is used . The results obtained after a 2 hours and 24 hours contact are reported . The resulting values of minimum inhibitory concentrations are comparable . As far as minimum bactericidal concentrations values are concerned, there is no significant difference between the two methods or between the two antibiotics . The analysis of the bactericidal effect of a 2 hours contact allows no inference relative to the comparative effect of the two antibiotics . Each strain of P . aeruginosa has its specific behaviour, and there seems to be no way to extrapolate from their minimum inhibitory concentrations the bactericidal effect of cefsulodin and ceftazidime. Mikrobiologiia, 1983 May-Jun, 52(3), 392 - 5 {Population dynamics of Pseudomonas aeruginosa capable of assimilating p-xylene}; Gorlatova NV et al.; The paper describes the dynamics of clones in the population of Pseudomonas aeruginosa 2x, which appear spontaneously as the result of variability in the capacity to use aromatic compounds . A culture growing on p-xylene is most homogeneous, which may be attributed to the selective action of the medium . However, the greatest number of cells capable of growth on p-xylene is found in a culture grown in a medium containing glucose. J Antimicrob Chemother, 1983 May, 11 Suppl B, 33 - 8 Synergy of azlocillin with aminoglycosides; Chin NX et al.; The combination of azlocillin and the aminoglycosides amikacin, gentamicin, netilmicin, sisomicin, and tobramycin was synergistic . The FIC index was less than or equal to 0.5 for 28 to 42% of Pseudomonas aeruginosa isolates tested and with an additive FIC index greater than 0.5-1 for 53 to 63% of the isolates . Antagonism was not encountered . Isolates resistant to azlocillin (MIC greater than 100 mg/l) were more often synergistically inhibited by the combination of azlocillin and an aminoglycoside . The concentrations of antibiotics that synergistically inhibited Pseudomonas were those readily achieved in man . The combination of azlocillin and aminoglycosides prevented regrowth of isolates that grew after initial suppression by the antibiotics alone. Antibiotiki, 1983 May, 28(5), 341 - 5 {Morphological study of the organs and tissues of mice infected after a burn with a Pseudomonas aeruginosa strain and treated with a Pseudomonas aeruginosa polyvalent corpuscular vaccine and tobramycin}; Moroz AF et al.; The effect of tobramycin and polyvalent corpuscular Ps . aeruginosa vaccine on the infectious process in mice with grade III burns inoculated with Ps . aeruginosa 1312 was studied . The highest percentage of the survival (100 per cent) among the animals was observed, when the vaccine was applied locally every day for 7 days . With the use of tobramycin administered intramuscularly for 2 times 95 per cent of the animals survived . When the vaccine was administered subcutaneously, 96.6 per cent of the animals survived . Morphological investigation of the organs and tissues of the mice showed that the vaccine applications to the infected burns promoted rapid elimination of microorganisms in the wounds and prevented development of sepsis due to Ps . aeruginosa . At the same time early epithelization of the wounds was observed (by the 4th-7th day) . Intramuscular injections of tobramycin and subcutaneous injection of vaccine also prevented development of sepsis due to Ps . aeruginosa and protected the animals from death . Still no epithelization of the wounds by that period was observed . Microscopic examinations revealed necrosis of the epiderma and derma elements and microbial swarms on the skin surface. Zh Mikrobiol Epidemiol Immunobiol, 1983 May, (5), 25 - 8 {Electron microscope study of the intracellular development of the Pseudomonas aeruginosa bacteriophage phi KZ}; Smirnova TA et al.; The study of the ultrathin sections of cells infected with virulent phage phi KZ has confirmed the presence of a specific cylindrical formation, an inner body, in the head of this phage and revealed the spiral structure of this inner body . The formation of DNA condensates whose structure resembles a spring wound around the core (the inner body) has been shown to occur in the cells in the process of the ultracellular development of phage phi KZ . This development leads to characteristic changes in the cellular structure, and in particular in the cell walls and the nucleoid. Prikl Biokhim Mikrobiol, 1983 May-Jun, 19(3), 347 - 52 {A strain of Pseudomonas aeruginosa growing on petroleum hydrocarbons}; Porits AL et al.; The strain Pseudomonas aeruginosa BS313 was used to isolate mutants that are capable to utilize octane as the sole carbon source . By means of conjugation plasmids of camphor (CAM) and naphthalene (pBS2) biodegradation were inserted into one of the mutant strains P . aeruginosa BS316 . The resultant strain P . aeruginosa BS315 shows the capacity to degrade aliphatic, aromatic and cyclic oil hydrocarbons. Pediatr Infect Dis, 1983 May-Jun, 2(3), 209 - 11 Efficacy of inhaled tobramycin in the treatment of pulmonary exacerbations in children with cystic fibrosis; Stephens D et al.; Two forms of treatment of acute pulmonary exacerbations in patients with cystic fibrosis were compared: intravenous ticarcillin (300 mg drug per kg per day) and tobramycin (10 mg drug per kg per day) versus the same intravenous antibiotic therapy plus inhaled tobramycin (80 mg three times per day) . The 16 patients in the intravenous plus inhaled tobramycin group were similar to the 12 control patients in age, sex, Schwachman scores, pulmonary function and pretreatment colony counts of Pseudomonas aeruginosa in sputum . Treatment resulted in significant improvement in clinical status and pulmonary function without any apparent differences in the two groups . However, intravenous plus inhaled tobramycin resulted in temporary eradication of P . aeruginosa in 63% of the patients compared to 25% in the intravenous only group (P = 0.03) . Suppression of P . aeruginosa in sputum cultures did not correlate with clinical response to treatment . No renal toxicity or elevations of serum tobramycin were observed in the intravenous plus inhaled tobramycin group. Proc Natl Acad Sci U S A, 1983 May, 80(10), 2870 - 3 Pseudomonas exotoxin A: toxoid preparation by photoaffinity inactivation; Marburg S et al.; A method for toxoid preparation has been developed in which toxins expressing enzymatic activity can be detoxified by photoaffinity labeling techniques . In the case of Pseudomonas aeruginosa exotoxin A, the method relies on the affinity of azido-substituted analogs of the substrate (NAD) for the proenzyme form of the toxin . Photolysis of the putative toxin-analog complex results in irreversible inactivation of the toxin without loss of antigenic character . It is proposed that this occurs by nitrene insertion into a chemical bond on the toxin molecule . This affinity photoinactivation process should be applicable to other ADP-ribosylating toxins. Am Rev Respir Dis, 1983 May, 127(5), 605 - 8 The relationship of phenotype changes in Pseudomonas aeruginosa to the clinical condition of patients with cystic fibrosis; Penketh A et al.; Strains of Pseudomonas aeruginosa, isolated from the sputum of relatively fit patients with cystic fibrosis (CF) who had been recently colonized by the organism, showed typical cultural and serologic characteristics . The majority of strains of P . aeruginosa isolated from CF patients with chronic bronchopulmonary infection had 3 distinctive features, loss of 0 serotype reaction, expression of a new somatic antigen, and sensitivity to normal human serum . Patients with organisms with one or two of these features were more severely affected by the disease . The appearance of these variants may represent a critical stage in the progression of CF. J Bacteriol, 1983 May, 154(2), 780 - 6 Chemotaxis of Pseudomonas aeruginosa: involvement of methylation; Craven RC et al.; The involvement of a protein methyl transfer system in the chemotaxis of Pseudomonas aeruginosa was investigated . When a methionine auxotroph of P . aeruginosa was starved for methionine, chemotaxis toward serine, measured by a quantitative capillary assay, was reduced 80%, whereas background motility was unaffected or increased . When unstarved bacteria were labeled with L-{methyl-3H}methionine, a labeled species of 73,000 molecular weight which was methylated in response to stimulation by L-serine was identified . Under appropriate electrophoretic conditions, the 73,000 molecular weight species was resolved into two bands, both of which responded to stimulation by L-serine, L-arginine, and alpha-aminoisobutyrate (AIB) with an increased incorporation of methyl label . Arginine, which elicited the strongest chemotactic response in the capillary assay, also stimulated the greatest methylation response . Methylation of the 73,000 molecular weight species reached a maximum 10 min after stimulation by AIB and returned to the unstimulated level upon removal of the AIB . In vitro labeling of cell extracts with S-adenosyl{methyl-3H}methionine indicated that the 73,000 molecular weight species are methylated by an S-adenosylmethionine-mediated reaction . These results indicate that chemotaxis of P . aeruginosa toward amino acids is mediated by dynamic methylation and demethylation of methyl-accepting chemotaxis proteins analogous to those of the enteric bacteria. Infect Immun, 1983 May, 40(2), 670 - 4 In vitro response of human T cells to Pseudomonas aeruginosa; Porwoll JM et al.; Pseudomonas aeruginosa is a gram-negative bacillus that is a major cause of morbidity and mortality in immunosuppressed patients, burn patients, and patients with cystic fibrosis . Although immunity to these bacteria has been associated with serum antibody, more recent evidence suggests that T-cell-mediated immunity may also be important . To evaluate human T-cell responsiveness to these bacteria, the optimal conditions were determined for in vitro proliferation of human peripheral blood lymphocytes and T-lymphocytes to Fisher-Devlin immunotype 1 P . aeruginosa . The proliferative response of normal adult peripheral blood lymphocytes to heat-killed P . aeruginosa was studied in 34 subjects (range, 7,600 to 111,500 net cpm) . Analysis of cell subpopulations indicated that T-lymphocytes are the major proliferating cells and that this response is enhanced by the presence of adherent cells . Data from fetal cord lymphocyte responses suggest that the proliferation seen in normal adult lymphocytes is induced by antigenic and not mitogenic stimulation. Infect Immun, 1983 May, 40(2), 506 - 13 Protease production by Pseudomonas aeruginosa isolates from patients with cystic fibrosis; Hastie AT et al.; The temporal appearance of extracellular proteases produced by Pseudomonas aeruginosa was analyzed by pH 9 and pH 4 polyacrylamide gel electrophoresis (PAGE) and sodium dodecyl sulfate-PAGE . Ammonium sulfate precipitates of culture supernatants from various stages of growth revealed a time-dependent increase in number and amount of proteolytically active proteins . One mucoid P . aeruginosa clinical isolate and its derived nonmucoid variant, as well as two other nonmucoid variant P . aeruginosa strains (all from cystic fibrosis patients), showed similar production of five differently migrating proteases (P1 to P5, numbered according to increasing net negative charge) in pH 9 PAGE and one protease in pH 4 PAGE . P2, P3, and P5 increased to maximum concentrations at 24 to 48 h, decreasing thereafter, whereas P4 continued increasing even at 83 h, and P1 fluctuated . P3 was identified as an elastase . P2 was possibly composed of polypeptide chains bridged by disulfide bonds, since without reduction it migrated in sodium dodecyl sulfate-PAGE as a single protein, and with reduction it migrated as three protein bands . Two-dimensional PAGE revealed multiple molecular weight species within protease-positive bands in pH 9 gel strips . Isoelectric focusing gave a pattern of protein separation that correlated with two-dimensional PAGE analysis . Thus, greater heterogeneity of active proteases than previously reported has been demonstrated in all P . aeruginosa clinical isolates studied by sensitive two-dimensional PAGE analysis. Pathol Biol (Paris), 1983 May, 31(5), 366 - 9 {A study of pharmacokinetics of cefoperazone in children}; Begue P et al.; A study of the pharmacokinetics of cefoperazone (CPZ), used as the sole antibiotic, was performed in 17 children and neonates . The types of infections treated were 7 UTI, 2 otitis media, 2 RTI, 4 septicemia or severe neonatal infections . Causative bacteria included 6 E . coli, 3 Pseudomonas aeruginosa, 1 C perfringens, 1 Klebsiella pneumoniae and 2 Staphylococcus aureus . Cefoperazone was administered by means of rapid IV injections (over 5 min) or IV infusions BID . The blood samples were taken by means of capillary microtubes at time 0, 0.25, 0.50, 0.75, 1, 2, 4, 6, 8 and 12 hours after the end of the first injection . After centrifugation and freezing at -80 degrees DEG method using modified Difco M2 Agar (Nall plus sodium citrate) and stock organinism Bacillus subtilis Atcc 6633 . The results achieved in children and neonates were compared, in the 11 children (mean age 6.5 years) . The mean single dose was 53 mg/kg . The mean maxima concentration was 145 mcg/ml and was obtained at 0.5 h . Mean serum half-life is 2.4 h . For the neonates mean age was 16 days and the dosage was 47 mg/kg, the maxima concentration was 232 micrograms/ml and was obtained at 0.6 h . The mean serum half-life was 3.4 h in the 2 groups, serum levels at 12 h were still high with a mean of 6.2 micrograms/ml for the 17 children . It appears that doses of 25-50 mg/kg given BID would be satisfactory. J Antimicrob Chemother, 1983 May, 11 Suppl B, 205 - 14 Comparative efficacy and tolerance study of azlocillin and carbenicillin in patients with cystic fibrosis: a double blind study; Huang NN et al.; Azlocillin, a new acylureidopenicillin, has been compared to carbenicillin in a controlled, double-blind study for acute exacerbations of pulmonary infections in 29 patients with cystic fibrosis . Twenty-six patients were valid for final analysis of their therapeutic results; 12 treated with azlocillin (group I) at mean dosage of 252 mg/kg/day for a mean duration of 13.2 days of treatment, and 14 treated with carbenicillin (group II) at mean dosage of 505 mg/kg/day for a median duration of 12.6 days . Except for one patient of group I who had Staphylococcus aureus in sputum culture, the remaining patients all had Pseudomonas aeruginosa of mucoid colonial morphology with or without the same organism of rough variety in their sputum culture . Therapeutic efficacy was evaluated according to our scoring system of ten clinical factors, five radiological and five pulmonary function factors with 5 points each and 100 points total if perfect . The percentage of patients who improved by 20% or greater in clinical scores was found in 91.7% of patients in group I and 64.3% of patients in group II, which was statistically significantly different . The percentage of patients who improved by 20% or greater in total scores was found in 80% of group I and 45.5% of group II patients, which was less significant than the evaluation of clinical scores alone . Azlocillin was well tolerated and safe in the dosage employed . Its optimal dosage for patients with cystic fibrosis should be established. J Antimicrob Chemother, 1983 May, 11 Suppl B, 195 - 203 Randomized, double-blind evaluation of azlocillin for the treatment of pulmonary exacerbations of cystic fibrosis; McLaughlin FJ et al.; Patients with cystic fibrosis hospitalized because of deterioration in their pulmonary disease were randomly assigned to receive ten days of intravenous antibiotic therapy with either ticarcillin plus tobramycin (previously the standard regimen at our hospital), azlocillin plus tobramycin or azlocillin plus placebo . Pulmonary function and microbiological responses were similar in the three treatment groups, although patients receiving azlocillin and placebo tended to have a smaller reduction in the concentration of bacteria in the sputum and a greater rate of acquisition of antibiotic-resistant organisms . Overall, in-hospital treatment was associated with a significant improvement in Shwachman score, pulmonary function tests, and PO2 . Improvement was noted by day 5 of therapy, continued through day 10, and was partially maintained at follow-up clinic visit one month after discharge . There was also a statistically significant reduction in sputum bacterial concentration, but patients cultured at the conclusion of antibiotic therapy still had a mean of 10(7) cfu/ml in sputum . Pseudomonas aeruginosa, the principal pathogen recovered from sputum cultures in this study, was transiently suppressed to sub-detectable levels in only one patient . There was no correlation between microbiological response and change in any parameter of pulmonary function . By follow-up clinic visit, sputum bacteria had returned to pre-treatment levels, and antibiotic-resistant organisms persisted in all patients from whom they had been recovered during hospitalization. J Antimicrob Chemother, 1983 May, 11 Suppl B, 169 - 74 A comparison of azlocillin and gentamicin in the treatment of serious infections caused by Pseudomonas aeruginosa; Gonzalez MA; A randomized controlled clinical trial to compare the efficacy and safety of azlocillin and gentamicin was conducted in 42 patients with serious infections, primarily of the skin or skin structure and lower respiratory tract . Pseudomonas aeruginosa was isolated from each of the 25 infection sites in the azlocillin group and 18 in the gentamicin group; most of the sites were also infected by other pathogens . After a mean of 13 days of treatment with azlocillin at 18 g/day, a good clinical response was attained in 96% of the cases, and nearly 90% of the causative organisms were eradicated . In the gentamicin group, administration of 180 mg/day for a mean of 11 days provided a good clinical response in 95% of the cases, and eradication of 92% of the causative pathogens. J Antimicrob Chemother, 1983 May, 11 Suppl B, 159 - 67 A comparative study of the efficacy and safety of azlocillin and gentamicin in the treatment of serious infections; del Rosal PL; Azlocillin, a new semisynthetic ureidopenicillin, has increased in-vitro activity against Pseudomonas aeruginosa and good activity against other Gram-negative organisms . In a comparative clinical study, azlocillin was administered intravenously at 18 g/day to 24 patients and gentamicin intramuscularly at 3 to 5 mg/kg/day to 25 patients, most of whom had infections of the skin and skin structure, intra-abdominal cavity, or lower respiratory tract . Gram-negative organisms, usually Ps . aeruginosa or Escherichia coli, and Staphylococcus aureus, were isolated most frequently . At the end of therapy, 18/24 (75%) of the patients with one infection site had an excellent clinical response after azlocillin, as compared with 7/20 (35%) after gentamicin (P = 0.014) . The overall response to treatment was cure in 17/24 (70.8%) of the azlocillin patients and 9/24 (37.5%) of the gentamicin patients (P = 0.042) . Bacteriological response was in the azlocillin group 28/33 or 84.8% as compared to the gentamicin group 38/51 or 74.5%. J Gen Microbiol, 1983 May, 129 (Pt 5), 1527 - 36 Identification of Tn2401, a transposon encoding multiresistance to aminoglycosides; Schmidt F et al.; A transposable element, Tn2401, was found in a clinical isolate of Pseudomonas aeruginosa . Tn2401 had a size of 7190 nucleotides and encoded aminoglycoside 3'-phosphotransferase and aminoglycoside 6'-N-acetyltransferase . The sequence encoding the former enzyme was homologous with that of Tn903 . Pseudomonas aeruginosa strains harbouring this transposon were resistant to kanamycin, neomycin, lividomycin, ribostamycin, paromomycin, netilmycin, tobramycin, dibekacin, gentamicin, sisomicin, and butirosin. Infect Immun, 1983 May, 40(2), 665 - 9 Demonstration of an iron-siderophore-binding protein in the outer membrane of Pseudomonas aeruginosa; Sokol PA et al.; Outer membranes prepared from Pseudomonas aeruginosa grown in low-iron medium bind three times as much {59Fe}pyochelin as do membranes from cells grown in high-iron medium . The deletion of pyochelin reduced 59Fe binding to background levels . Autoradiographic analysis of sodium dodecyl sulfate polyacrylamide gel electrophoretograms of outer membrane preparations previously incubated with {59Fe}pyochelin revealed that the iron-siderophore complex bound to a low-molecular-weight protein of approximately 14,000. J Reprod Med, 1983 May, 28(5), 337 - 40 Treatment of serious obstetric and gynecologic infections with cefoxitin; Hager WD et al.; In order to evaluate the efficacy of cefoxitin, 25 patients with serious pelvic infections admitted to a community hospital were treated with the drug . Twenty-one patients (84%) responded to this therapy . Three of the four failures (75%) had a pelvic abscess . Resistant organisms included Staphylococcus aureus, Pseudomonas aeruginosa and enterococci . The adverse reactions encountered were due to localized phlebitis, which occurred in three patients (12%) . The study demonstrated that cefoxitin was successful as a single agent in the treatment of serious soft-tissue pelvic infections. J Bacteriol, 1983 May, 154(2), 623 - 31 Hidden overflow pathway to L-phenylalanine in Pseudomonas aeruginosa; Fiske MJ et al.; Pseudomonas aeruginosa is representative of a large group of pseudomonad bacteria that possess coexisting alternative pathways to L-phenylalanine (as well as to L-tyrosine) . These multiple flow routes to aromatic end products apparently account for the inordinate resistance of P . aeruginosa to end product analogs . Manipulation of carbon source nutrition produced a physiological state of sensitivity to p-fluorophenylalanine and m-fluorophenylalanine, each a specific antimetabolite of L-phenylalanine . Analog-resistant mutants obtained fell into two classes . One type lacked feedback sensitivity of prephenate dehydratase and was the most dramatic excretor of L-phenylalanine . The presence of L-tyrosine curbed phenylalanine excretion to one-third, a finding explained by potent early-pathway regulation of 3-deoxy-D-arabinoheptulosonate 7-phosphate (DAHP) synthase-Tyr (a DAHP synthase subject to allosteric inhibition by L-tyrosine) . The second class of regulatory mutants possessed a completely feedback-resistant DAHP synthase-Tyr, the major species (greater than 90%) of two isozymes . Deregulation of DAHP synthase-Tyr resulted in the escape of most chorismate molecules produced into an unregulated overflow route consisting of chorismate mutase (monofunctional), prephenate aminotransferase, and arogenate dehydratase . In the wild type the operation of the overflow pathway is restrained by factors that restrict early-pathway flux . These factors include the highly potent feedback control of DAHP synthase isozymes by end products as well as the strikingly variable abilities of different carbon source nutrients to supply the aromatic pathway with beginning substrates . Even in the wild type, where all allosteric regulation in intact, some phenylalanine overflow was found on glucose-based medium, but not on fructose-based medium . This carbon source-dependent difference was much more exaggerated in each class of regulatory mutants. Med J Aust, 1983 Apr 16, 1(8), 381 - 3 Pseudomonas folliculitis associated with the use of health-spa whirlpools; Gibson AR et al.; The occurrence of pustular folliculitis in eight people after the use of health-spa whirlpools is described for the first time in Australia . The lesions were discovered ad identified during the peak season in two resorts in the Snowy Mountains area near Jindabyne, New South Wales . Pseudomonas aeruginosa, identified as serotype 0:6, was isolated from pus swabs of the lesions, water in the spa pools and pool filters. S Afr Med J, 1983 Apr 9, 63(15), 562 - 3 Treatment of otitis externa with miconazole nitrate . A comparative study involving 85 cases; Bak JP et al.; The hazards of neomycin in local preparations have recently been re-emphasized . Eighty-five patients with otitis externa were treated with one of two preparations between August 1980 and April 1982 -- 54 were treated with a cream containing miconazole nitrate and hydrocortisone (Daktacort; Janssen) and 31 with a preparation containing neomycin (Kenacomb; Squibb); Sixty eight per cent of the patients were cured within 1 week with both preparations . Most treatment failures were due to a resistant Pseudomonas aeruginosa . The miconazole cream proved as effective as the preparation containing neomycin in the first-line treatment of otitis externa . A gentamicin-containing steroid ointment was effective against the Pseudomonas infection. Br J Dis Chest, 1983 Apr, 77(2), 179 - 84 Ticarcillin compared with carbenicillin in the treatment of exacerbations of bronchopulmonary infection in cystic fibrosis; Penketh AR et al.; Sixteen adults with cystic fibrosis and chronic bronchopulmonary infection with Pseudomonas aeruginosa, admitted to hospital for chemotherapy, were randomized to treatment with either carbenicillin or ticarcillin . In addition all patients received gentamicin . Both antibiotic treatments produced clinical improvement and significant improvement in respiratory function, but there was no difference between them . Pseudomonas aeruginosa was not eradicated from sputum with either treatment regimen. Br J Exp Pathol, 1983 Apr, 64(2), 231 - 7 Therapeutic significance of nocardicin A stimulation of phagocyte function in experimental Pseudomonas aeruginosa infection; Banks RM et al.; Nocardicin A, a monocyclic beta-lactam antibiotic with modest anti-pseudomonal activity in vitro, controlled an otherwise fatal Pseudomonas infection in mice when given in doses which produced blood levels well below the minimum bactericidal concentration . In even smaller doses, it converted the partial protection afforded by modest doses of carbenicillin into full protection . Human polymorphonuclear leucocytes exposed to low concentrations of the drug in vitro and peritoneal macrophages recovered from mice treated with nocardicin A exhibited an unusually specific form of enhanced activity . Chemotaxis and phagocytosis were not affected, but intracellular killing of Ps . aeruginosa was significantly increased . This was shown to be due to an effect on the phagocyte and not to facilitated killing of organisms damaged by extracellular exposure to the antibiotic . It is argued that the effect on phagocyte function is sufficient to contribute materially to the therapeutic effect of nocardicin A. Proc Soc Exp Biol Med, 1983 Apr, 172(4), 488 - 91 Dominant susceptibility effect on the murine corneal response to Pseudomonas aeruginosa; Beisel KW et al.; Natural host resistance to Pseudomonas aeruginosa corneal infection is regulated by two complementing dominant genes PsCR1 and PsCR2 (RS Berk, MA Leon, LD Hazlett . Infect Immun 26:1221-1223, 1979) . In this study we have demonstrated a third dominant gene, which determines susceptibility to P . aeruginosa-induced eye damage . This gene was designated as PsCS . The F1 progeny from matings between the resistant DBA/2J strain and the susceptible strain C57BL/6J and C3H/HeJ displayed the susceptibility phenotype . Backcross and F2 studies using the C3H/HeJ and DBA/2J strains suggested the presence of two linked PsCS loci. Ann Thorac Surg, 1983 Apr, 35(4), 436 - 41 Valve replacement for left-sided endocarditis in drug addicts; Mammana RB et al.; Eighteen drug addicts with left-sided valvular endocarditis requiring operation are reviewed . Gram-positive bacteria were the most common organisms cultured (61%), with Staphylococcus aureus present in 7 of 11 patients . Gram-negative bacteria, exclusively Pseudomonas aeruginosa, were cultured in the remaining 39% . Indications for operation included sepsis (61%), heart failure (78%), and systemic emboli (22%) . Abscesses formed in 6 of 11 patients with gram-positive endocarditis, while only one abscess was present with gram-negative endocarditis . Normal valves were infected in 17 of 18 patients (94%) . Early surgical mortality (less than 30 days) was 11% . There were major complications in 79% of these patients, including persistent sepsis (50%), valvular dehiscence, prosthetic endocarditis or perivalvular leakage (37%), and mycotic aneurysms (22%) . These complications were directly related to a late mortality of 44%, yielding an overall mortality of 50% in the first nine months after operation . Contrary to previous reports of acceptable surgical survival for valvular endocarditis, these data suggest that endocarditis involving the aortic or mitral valve in a drug addict is a highly lethal disease due to the virulence of the organisms, the severity of the complications encountered, and the predisposition to continued addiction. J Gen Microbiol, 1983 Apr, 129 (Pt 4), 981 - 8 Effect of substrate on the regulation of exoprotease production by Pseudomonas aeruginosa ATCC 10145; Whooley MA et al.; Exoprotease production by Pseudomonas aeruginosa ATCC 10145 was growth-associated when cultures were grown on complex substrates such as proteins but it occurred during the decelerating growth phase when the organism was grown on amino acids, mixtures of amino acids or simple carbon sources . NH4Cl and simple carbon sources caused repression . Exoprotease was produced in chemostat cultures in response to growth under any of the nutrient limitations studied (carbon, nitrogen or phosphate) . Furthermore, by growing at rates less than approximately 0.1 h-1, the repression of enzyme production could be overcome to a large degree . At low growth rates there was an inverse relationship between growth rate and exoprotease production . Thus, exoprotease production was depressed by available energy sources and was increased in response to any nutrient limitation. Zh Mikrobiol Epidemiol Immunobiol, 1983 Apr, (4), 45 - 50 {Aerobic and facultatively anaerobic bacteria isolated from surgical infection patients}; Iskhakova KhI et al.; The ecological structure of infections in surgical patients with different postoperative complications (suppurative wounds, abscesses, peritonitis, etc.) and suppurative lung diseases were studied . During the period of 6 years (1975-1980) 5401 samples of clinical material were studied . 1380 samples (25.6%) were sterile, from 2254 samples (41.7%) monocultures were isolated, in 1767 samples (32.7%) microbial associations were detected . Of 5962 isolated cultures, 1816 (30.5%) were Gram-negative bacteria (GNB), 3532 (59.2%) were Gram-positive bacteria (GPB) and 614 (10.6%) were yeastlike fungi . The tendency towards the increase of the role of GNB in the etiology of postoperative complications was observed . Among GNB Pseudomonas aeruginosa strains were prevalent (36.2%) . In the group of GPB coagulase-negative staphylococci were rather frequently found to be the causative agents of surgical infections. Zh Mikrobiol Epidemiol Immunobiol, 1983 Apr, (4), 30 - 3 {Antibiotic sensitivity of different antigenic variants of Pseudomonas aeruginosa isolated in a hospital}; Sheina EP et al.; The serological typing of 96% of P . aeruginosa strains isolated in hospitals has been carried out by means of agglutinating sera, and the tendency towards the prevalence of the strains of group V (25.3%) and serovar O11 (18.1%) has been revealed . The determination of the antibiotic sensitivity of different variants has shown that the strains of groups I, V and serovar O11 possess pronounced resistance to a wide spectrum of antibiotics, their resistance to gentamycin and polymixin being higher than in the strains of other serotypes . The determination of antibiotic resistance can serve only as an additional test in the serological typing of P . aeruginosa. J Clin Lab Immunol, 1983 Apr, 10(4), 221 - 4 Inhibition of bacterial binding to mouse macrophages by Pseudomonas alginate; Oliver AM et al.; Alginate, an acetylated polymer of D-mannuronic and L-guluronic acid obtained from a mucoid strain of Pseudomonas aeruginosa was shown to inhibit the binding of an isogenic non-mucoid revertant to mouse peritoneal and pulmonary macrophages . Inhibition of bacterial binding by the alginate was also demonstrated in tests with other non-mucoid P . aeruginosa strains and a strain of Staphylococcus albus . Since the mucoid form of P . aeruginosa eventually predominates in chronic P . aeruginosa infection in patients with cystic fibrosis, it is postulated that the alginate's inhibition of binding gives mucoid forms a selective advantage over non-mucoid forms against macrophage defence mechanisms in the lung. Can J Microbiol, 1983 Apr, 29(4), 448 - 56 Pseudomonas aeruginosa exoproducts as pulmonary virulence factors; Cash HA et al.; An experimental animal model of chronic pseudomonas pneumonia was used to document the production of potential virulence factors by Pseudomonas aeruginosa during the infection . The production of exotoxin A, proteolytic enzymes, and the serotype-specific lipopolysaccharide and slime-layer antigens during the infection was examined by solid-phase radioimmunoassay of serum from infected rats and by indirect immunofluorescence tests of their lung tissue . Rats inoculated intratracheally with purified bacterial exoproducts, delivered alone or in combination, developed pulmonary histopathology similar to that induced by the experimental infection . The results indicate that these exoproducts are produced during the course of the pulmonary infection and suggest that they are involved in the observed lung pathology. Proc Soc Exp Biol Med, 1983 Apr, 172(4), 449 - 56 In vivo adherence of Pseudomonas aeruginosa to rat bladder epithelium; Vardi Y et al.; To date, the study of bacterial adherence to uroepithelial cells has utilized considerable variation in methodology, resulting in highly divergent conclusions . In an attempt to standardize methodology, a modified method is described to more accurately measure the in vivo bacterial adherence to rat bladder uroepithelium utilizing Pseudomonas species labeled with 2-{3H}adenine . Two isolates of P . aeruginosa were selected for more intensive study; one showed consistently good adherence; the second strain always adhered poorly, thus providing a negative control . Maximum adherence was detected after 60 min of incubation . Neither of the two Pseudomonas isolates when examined by transmission electron microscopy showed evidence of pili formation . The morphological features of Pseudomonas adherence to bladder mucosa as studied by scanning electron microscopy are described. J Infect Dis, 1983 Apr, 147(4), 744 - 50 Proteases of Pseudomonas aeruginosa in patients with cystic fibrosis; Doring G et al.; Radioimmunoassays were used to determine titers of antibody to alkaline protease (AP) and elastase (Ela) produced by Pseudomonas aeruginosa in sera and bronchial secretions, in vitro production of AP and Ela by P . aeruginosa isolates, and occurrence of these enzymes in bronchial secretions from patients with cystic fibrosis . Titers of serum antibodies to AP ranging from 1:10 to 1:545 and to Ela ranging from 1:10 to 1:725 were found in 83%-88% of patients with cystic fibrosis and chronic lung infections due to P . aeruginosa . Antibody titers in liquified bronchial secretions were approximately 10% of the serum titers . Thirty-one (93%) of 34 isolates produced both proteases in vitro in comparable amounts (concentration of protease in culture supernatant: AP, 0.01-480 micrograms/ml; Ela, 0.02-490 micrograms/ml) . AP and Ela were detected in vivo when antibodies to the enzymes were absent . The results suggest that specific immune responses in patients with cystic fibrosis neutralize proteases of P . aeruginosa. J Bacteriol, 1983 Apr, 154(1), 383 - 6 Locus of the Pseudomonas aeruginosa toxin A gene; Hanne LF et al.; The gene for Pseudomonas aeruginosa toxin A has been mapped in the late region of the chromosome of strain PAO . Strain PAO-PR1, which produces parental levels of toxin A antigen that is enzymatically inactive and nontoxic, was used as the donor for R68.45 plasmid-mediated genetic exchange . Strain PAO-PR1 (toxA1) was mated with toxin A-producing strains, and exconjugates for selected prototrophic markers were tested for the transfer of toxA1 . The toxA1 gene was located between cnu-9001 and pur-67 at approximately 85 min on the PAO chromosome. J Surg Res, 1983 Apr, 34(4), 298 - 302 Prostacyclin in experimental septic acute respiratory failure; Steinberg SM et al.; Manipulation of prostaglandins (PG) in animal models of sepsis and acute respiratory failure (ARF) is promising . Prostacyclin (PGI2), a short-acting vasodilator, was evaluated in a porcine model of ARF produced by continuous infusion of live Pseudomonas aeruginosa (Ps.) . Cardiopulmonary parameters were monitored in three groups of spontaneously breathing animals that received 0.1 micrograms PGI2/kg/min begun 20 min after baseline (Group I); 2 X 10(8) Ps./20 kg/min (Group II); identical Ps . infusion and then PGI2 begun at 20 min (Group III) . The decrease in mean arterial blood pressure and cardiac index with Ps . infusion was improved by PGI2 treatment . In Groups II and III, mean pulmonary artery pressure (PAP) doubled (P less than 0.005) and pulmonary vascular resistance (PVR) tripled (P less than 0.01) by 15 min . Both PAP and PVR were decreased significantly with PGI2 treatment . In both Ps . groups, significant hypoxemia occurred . PGI2 improves cardiac output and acts as a pulmonary vasodilator, but does not improve oxygenation in this porcine model of severe ARF. Zentralbl Bakteriol Mikrobiol Hyg {A}, 1983 Apr, 254(2), 253 - 60 {Cefoperazone, cefsulodin and ceftazidime--3 cephalosporins active against Pseudomonas in comparison with their monobactam analogs}; Baumgartner M; This study compares the in vitro activity of three cephalosporins - ceftazidime, cefoperazone, cefsulodin and their monobactam analogues for 144 strains of Pseudomonas aeruginosa . Media variation studies are performed and the effect of human serum and anaerobic conditions on MIC is investigated . A significant inoculum effect is considered as a sign of instability against beta-lactamases . Ceftazidine inhibits nearly all pseudomonads at concentrations between 2 and 4 micrograms/ml being significantly more active than the other antibiotics tested . The level of activity of all monobactams tested is lower than that of the homologous cephalosporins . The counterpart of ceftazidine is also the most effective monobactam but the counterpart of cefsulodin shows no activity against pseudomonads. J Gen Microbiol, 1983 Apr, 129 (Pt 4), 989 - 96 The protonmotive force in Pseudomonas aeruginosa and its relationship to exoprotease production; Whooley MA et al.; In Pseudomonas aeruginosa ATCC 10145 a negative correlation was observed between the protonmotive force (delta P) and the amount of exoprotease produced, with a decrease in delta P resulting in an increase in exoprotease . The two components of delta P, the transmembrane pH gradient (delta pH) and the membrane potential (delta psi) were examined independently and it was observed that delta psi varied very little under the conditions which influenced the activities of exoprotease . However, a positive correlation existed between pH and exoprotease production although the intracellular pH varied very little with either changes in growth rate or changes in extracellular pH . It was observed that with a decrease in growth rate, delta pH became more alkaline and increased exoprotease activities were recorded . Furthermore, an increase in extracellular pH to give an artificial alteration in delta pH, and, consequently, a decrease in delta P, increased exoprotease production, thus confirming the importance of delta pH in exoprotease production. Geburtshilfe Frauenheilkd, 1983 Apr, 43(4), 217 - 9 {Determination of concentration of an antibiotic (Cefotaxim) in the vaginal mucosa after preoperative intravenous administration}; Hagele D et al.; In 11 patients in whom an antibiotic (Cefotaxim) had been applied preoperatively, the tissue concentration was determined in the vaginal mucosa where postoperative infections after gynaecological operations are most common . The tissue concentration is compared with the minimum inhibition concentration of the pathogens identified directly before the operation in the cervicovaginal flora . In the case of the aerobic pathogens--with the exception of Pseudomonas aeruginosa--the concentration is far in excess of the necessary MIC, whereas with the anaerobic pathogens the concentration is only partly greater than the MIC . Resistance exists against Bacteroides fragilis. J Biochem (Tokyo), 1983 Apr, 93(4), 1137 - 44 Membrane-bound respiratory chain of Pseudomonas aeruginosa grown aerobically . A KCN-insensitive alternate oxidase chain and its energetics; Matsushita K et al.; There was found to be a KCN-insensitive, alternate oxidase chain branching from the ordinary oxidase chain in the respiratory chain of Pseudomonas aeruginosa grown aerobically . The alternate oxidase activity was highly resistant to KCN, and had a lower affinity for oxygen than ordinary cytochrome oxidase did . The branching point of the alternate oxidase chain from the ordinary oxidase chain was shown to be localized behind cytochrome b . The KCN-insensitive alternate oxidase chain was inhibited slightly with antimycin A and intensively with 2-thenoyltrifluoroacetone . The former inhibited the respiration behind cytochrome b and the latter before cytochrome b . N,N,N',N'-Tetramethyl-p-phenylenediamine oxidase-negative mutant (T105) was prepared from P . aeruginosa . The mutant clearly lacked a functional ordinary cytochrome oxidase, but had the KCN-insensitive alternate oxidase chain and could grow aerobically . The KCN-insensitive alternate oxidase chain had a H+/O ratio of 4, suggesting the existence of two energy-coupling sites in the chain . Under the conditions where both ordinary oxidase and alternate oxidase chains were functioning, the H+/O ratio of the parent strain was 5.6 . From these data, we also discuss the energetics of the ordinary oxidase chain in the respiratory chain of aerobic P . aeruginosa. Gene, 1983 Apr, 22(1), 95 - 101 Characterization of the phospholipase C gene of Pseudomonas aeruginosa cloned in Escherichia coli; Lory S et al.; We have cloned a 4.9-kb fragment of Pseudomonas aeruginosa DNA containing the structural gene of phospholipase C (PLC), by inserting it into the BamHI site of plasmid pBR322 . Strains of Escherichia coli carrying this recombinant plasmid produce PLC, but expression of the gene differs from that in P . aeruginosa in two respects: (i) synthesis of the enzyme appears to be constitutive, i.e., not repressible by the presence of inorganic phosphate in the growth medium, and (ii) most of the enzyme remains associated with the outer membrane instead of being secreted . Insertion mutagenesis at a unique restriction site within the PLC gene destroyed the ability of the plasmid to code, in maxicells, for phospholipase C activity and for an Mr 80000 polypeptide. JAMA, 1983 Mar 25, 249(12), 1615 - 7 Stimulatory effect of Pseudomonas aeruginosa on mucin secretion by the respiratory epithelium; Adler KB et al.; Cell-free filtrates of broth cultures from 11 of 18 strains of Pseudomonas aeruginosa isolated from patients with cystic fibrosis (CF) (or from patients without CF) increased substantially the secretion of mucin by explants of trachea from guinea pigs and human tracheal tissue obtained at autopsy . The effect was not related to the mucoid nature of the isolates, was not destroyed by heating at 90 degrees C for 30 minutes, and was not dependent on serotype . As P aeruginosa commonly infects the respiratory tracts of persons with CF, elaboration of an extracellular product that stimulates mucin secretion could play a role in the pathogenesis of the disease in the airways. J Biol Chem, 1983 Mar 25, 258(6), 4007 - 11 On the DNA binding protein II from Bacillus stearothermophilus . II . The amino acid sequence and its relation to those of homologous proteins from other prokaryotes; Kimura M et al.; The complete amino acid sequence of DNA binding protein II from Bacillus stearothermophilus has been determined . The protein contains 90 amino acid residues and has a calculated Mr of 9716 . The sequence is compared to homologous molecules from Escherichia coli, Thermoplasma acidophilum, and Pseudomonas aeruginosa (where only a partial sequence is available) . The B . stearothermophilus molecule has 58% and 59% residues identical with the two forms of the E . coli protein and 32% with the T . acidophilum protein . There are totally conserved residues at positions 46-48 and 61-65 with an intervening cluster of basic amino acids in all four proteins. Bull Eur Physiopathol Respir, 1983 Mar-Apr, 19(2), 151 - 61 Pseudomonas respiratory infection in cystic fibrosis: a possible defect in opsonic IgG antibody? Fick RB, Reynolds HY. Chronic Pseudomonas aeruginosa infections of the respiratory tract of people with cystic fibrosis (CF) usually are impossible to eradicate and greatly influence their health and longevity . General mechanisms of host defense are not impaired in this disease, except that serum does not support optimal phagocytosis of pseudomonas bacteria by alveolar macrophages and lung ciliary clearance is diminished, perhaps because of the accumulation of tenacious, purulent secretions in bronchiectatic airways and not by a defect in cilia structure or inhibitors of ciliary function . To investigate the defect in phagocytosis, we postulated that opsonic antibody might not be functioning well . Samples of purified IgG antibody against the typical strain of mucoid pseudomonas were prepared on immunoadsorbents, using CF sera and normal sera from volunteers previously immunized with a pseudomonas vaccine . CF IgG opsonin was found to agglutinate and coat well pseudomonas, but not to adhere or attach well to the surface of human alveolar macrophages, hence a defect in the function of the Fc portion of IgG was noted . In extending this analysis to CF lung secretions obtained by bronchoalveolar lavage, IgG antibody was purified exactly as from serum . Although this IgG had good agglutinating activity, much of it was fragmented (5 S size) and found to lack its Fc portion . It was evident that proteolytic enzymes in the purulent lavage secretions could cleave IgG . This activity was localized to a metallo-proteinase elaborated by the mucoid strain of pseudomonas . Thus, CF IgG may have reduced opsonic antibody function because of a molecular change in the Fc portion; this defect is magnified in the infected CF lung where a bacterial protease can actually fragment IgG and further impair its opsonic activity which is already marginal. Infect Immun, 1983 Mar, 39(3), 1428 - 40 Crossed immunoelectrophoretic analysis of Legionella pneumophila serogroup 1 antigens; Collins MT et al.; By crossed immunoelectrophoresis, 85 different antigens were demonstrated in sonicated preparations of Legionella pneumophila serogroup 1 (Lp1) . The precipitin patterns of 82 anodic-migrating antigens were numbered and were designated the Lp1 reference system . Eleven antigens were stable to boiling, and seven of these were shown to be surface antigens . One heat-stable surface antigen (antigen no . 61) was highly reactive with limulus amoebocyte lysates and formed a precipitin resembling lipopolysaccharide . Serum from an isolation confirmed case of Lp1 infection and serogroup-specific rabbit antiserum reacted specifically with antigen no . 61, which was designated the serogroup-specific antigen . Normal human and rabbit sera commonly had antibodies to antigen no . 66 of the Lp1 reference system . This antigen is antigenically related to the "common antigen" of Pseudomonas aeruginosa. Arch Surg, 1983 Mar, 118(3), 310 - 20 Wound healing accelerated by Staphylococcus aureus; Levenson SM et al.; While comparing the effects on wound healing of a heated scalpel with those of the cold scalpel, we discovered that inoculation of rat skin incisions with a strain of Staphylococcus aureus dramatically accelerated the gain in wound strength . The accelerating effect was evident four days postoperatively, was maximal at seven to ten days, and was still present at 28 days . The accelerating effect was correlated with the number of S aureus organisms introduced into the wound, and was found in conventional rats and rats germ free up to the time of monocontamination with S aureus . There was no evidence of infection on gross examination; on histologic examination an occasional microabscess was seen in some rats . There may be both local and systemic mechanisms underlying the S aureus accelerating effect . Seven strains of S aureus with varying characteristics demonstrated the wound-healing accelerating effect . In sharp contrast, Staphylococcus epidermidis (three strains), Staphylococcus hominis (one strain), and Pseudomonas aeruginosa (two strains) did not show this effect . The increases in wound healing due to S aureus were substantially greater than reported previously for any nutritional supplement, drug, or other chemical or physical agent. Arch Surg, 1983 Mar, 118(3), 291 - 4 Subeschar treatment of burn-wound infection; McManus WF et al.; Within a 24-month period, 454 patients were admitted with burns (average size, 33% of the total body surface {TBS}) . Wound infection developed in 19, who subsequently were treated with subeschar antibiotics . The average burn size in those 19 patients was 63% of the TBS, with an average full-thickness injury of 47% . Five (26%) of the 19 survived, and five others died without evidence of wound infection, giving a would clearance rate of 52.6% . The five surviving patients (average burn size, 59% TBS) underwent excision of infected tissue, with split-thickness cutaneous autograft closure of the burn wound, after the course of subeschar antibiotic infusion . All surviving patients were infected with Pseudomonas aeruginosa . Subeschar infusion of semisynthetic penicillins, therefore, is an effective adjunct in the care of the patient with Pseudomonas burn-wound infection. Infection, 1983 Mar-Apr, 11(2), 87 - 96 Studies of lung infections caused by Pseudomonas aeruginosa in mice treated with cyclophosphamide; Mayer P et al.; An experimental Pseudomonas aeruginosa lung infection was induced by aerosol exposure in mice which had been pretreated with cyclophosphamide . A single dose of 200 mg/kg cyclophosphamide resulted in leukopenia which lasted for three days . At the lowest PMN levels, the mice were exposed to aerosols containing varying doses of bacteria . The survival time of the mice and the number of viable bacteria in their lungs were determined . A dramatic rise in the viable counts of Pseudomonas organisms was found between 18 and 24 hours after infection . Mice which had not been pretreated with cyclophosphamide remained healthy and did not show any lung lesions . The number and phagocytic function of the alveolar macrophages remained unaltered after cyclophosphamide treatment . Thus, PMNs seem to play an important role in the lung's early defence mechanisms against Pseudomonas aeruginosa . This animal model could be of use in evaluating additional therapies for lung infections caused by Pseudomonas aeruginosa. Antibiotiki, 1983 Mar, 28(3), 199 - 204 {Ultrastructural changes in Pseudomonas aeruginosa cells as affected by gentamycin in in vitro and in vivo experiments}; Seleznev AS et al.; Morphological changes in phagocytosed cells of Pseudomonas aeruginosa under the effect of gentamicin were studied with electron microscopy using ultrathin slices . Peritoneal macrophages induced by irritation of the peritoneum with medium 199 followed by inoculation with a 1-milliard suspension of Pseudomonas aeruginosa were used . Gentamicin was administered intramuscularly in single doses of 10, 20 and 50 mg/kg . The effect of gentamicin was also studied in vitro . The in vitro studies showed that gentamicin induced rarefaction of the cytoplasm in Pseudomonas aeruginosa, elimination of the nuclear material, formation of membrane structures and separation of the cytoplasmic membrane from the cell wall . The studies with exposure of phagocytosed bacteria to gentamicin showed that the phagocytosed bacterial cells had the most pronounced changes in their ultrastructure . Under the effect of gentamicin in a dose of 50 mg/kg there appeared 2 types of the cells with changes not observed in vitro . Investigation of the digestive capacity of phagocytes demonstrated that gentamicin favoured an increase in the phagocytic activity and digestive capacity. Zh Mikrobiol Epidemiol Immunobiol, 1983 Mar, (3), 78 - 83 {Experimental study of the dynamics of the formation of protective antibodies to the antigens of the slime of Pseudomonas aeruginosa}; Iushkova NA et al.; Extracellular slime has been isolated, and partially purified, from P . aeruginosa 170006 (O3a, 3d, 3e: H1), a museum typing strain . The isolated strain has been used as immunogen . Extracellular slime has been found to stimulate the formation of circulating antibodies in rabbits, detected in the passive hemagglutination (PHA) test and in the passive mouse protection test . The subcutaneous immunization of rabbits with a large nontoxic dose of the antigen in Freund's adjuvant and the subsequent intravenous immunization with two large doses of the slime stimulate the intensive synthesis of protective antibodies and antibodies detected in the PHA test . The subcutaneous immunization of rabbits with small doses of the antigen in Freund's adjuvant and the subsequent intravenous injections of the slime also stimulate the synthesis of protective antibodies, but the level of antibodies detected in the PHA test remains low . Rabbit antiserum to P . aeruginosa 170006 slime antigens protects mice also from the intraperitoneal infection with the heterologous strain P . aeruginosa 170015 (O7a, 7b: H2a, 2c). Rev Infect Dis, 1983 Mar-Apr, 5(2), 314 - 21 Current problems in the treatment of infective endocarditis due to Pseudomonas aeruginosa; Reyes MP et al.; Mortality from pseudomonas infective endocarditis remains high despite optimal use of available antibacterial agents . Infection of the tricuspid valve is subacute, but involvement of the mitral or aortic valve precipitates more serious disease . Most valvular infections are due to a single pseudomonad immunotype, but 20% of cases are mixed infections . Antimicrobial susceptibility tests and tests of synergy by beta-lactam and aminoglycoside antibiotics in combination were performed on 30 isolates of Pseudomonas aeruginosa . Azlocillin was the most effective beta-lactam in combination with an aminoglycoside; MKO 787 was least effective . Among the aminoglycosides tested, netilmicin was the most effective . Medical treatment combined with valvulectomy (without valve replacement) is now standard treatment for refractory right-sided endocarditis at this medical center . A high dose of aminoglycoside in combination with a beta-lactam has proved efficacious . For left-sided infection, immediate valve replacement accompanied by a six-week course of the high dose-combined drug regimen is recommended . Newer beta-lactam antibiotics, such as piperacillin, may be limited in usefulness due to beta-lactamase inactivation. Rev Infect Dis, 1983 Mar-Apr, 5(2), 279 - 313 Infections caused by Pseudomonas aeruginosa; Bodey GP et al.; Pseudomonas aeruginosa has emerged as an important pathogen during the past two decades . It causes between 10% and 20% of infections in most hospitals . Pseudomonas infection is especially prevalent among patients with burn wounds, cystic fibrosis, acute leukemia, organ transplants, and intravenous-drug addiction . P . aeruginosa is a common nosocomial contaminant, and epidemics have been traced to many items in the hospital environment . Patients who are hospitalized for extended periods are frequently colonized by this organism and are at increased risk of developing infection . The most serious infections include malignant external otitis, endophthalmitis, endocarditis, meningitis, pneumonia, and septicemia . The likelihood of recovery from pseudomonas infection is related to the severity of the patient's underlying disease process . The introduction of the antipseudomonal aminoglycosides and penicillins has improved substantially the prognosis of these infections . Ticarcillin and carbenicillin have been especially beneficial in neutropenic patients; however, prompt institution of therapy is mandatory for optimal benefit . Many new drugs with antipseudomonal activity, including penicillins, cephalosporins, and other beta-lactams, have been introduced in recent years and offer the potential for new approaches to therapy for these infections. Infect Immun, 1983 Mar, 39(3), 1441 - 56 Cross-reactions between Legionella pneumophila (serogroup 1) and twenty-eight other bacterial species, including other members of the family Legionellaceae; Collins MT et al.; Cross-reactions between Legionella pneumophila serogroup 1 and 28 other bacterial species were studied by various quantitative immunoelectrophoretic techniques . A sonicated L . pneumophila antigen and purified homologous rabbit antibody were used as a reference system . Few antigens (0 to 6) cross-reacted with non-Legionellaceae, but two were found in nearly all gram-negative bacteria tested (antigens no . 1 and 66) . Antigen no . 66 of the L . pneumophila reference system was shown to be antigenically similar to the "common antigen" of Pseudomonas aeruginosa reported in many gram-negative bacteria . Greater than 85% of the antigens from L . pneumophila serogroup 1 cross-reacted with the other six serogroups of L . pneumophila . By contrast, Fluoribacter (Legionella) bozemanae, F . (L.) dumoffii, F . (L.) gormanii, and Tatlockia (Legionella) micdadei cross-reacted with only 45, 53, 39, and 43% of the reference system antigens, respectively . The antigenic relatedness of members of the Legionellaceae, expressed as a matching coefficient, is discussed in terms of its taxonomic significance . Serogroup-, genus-, and family-specific antigens are identified in the L . pneumophila reference system. Infect Immun, 1983 Mar, 39(3), 1403 - 10 Chronic colonization of rat airways with Pseudomonas aeruginosa; Boyd RL et al.; Colonization of the airways of rats by Pseudomonas aeruginosa was established by treating the animals with hexamethylphosphoramide (HMPA) and inoculating with P . aeruginosa . Male Sprague-Dawley rats were given tap water (controls) or HMPA in the drinking water at 2 or 4 mg/ml . The ciliated cells of the airway epithelium were denuded, and microulcerative lesions in the epithelium were induced in the HMPA-treated rats . After 2 weeks of treatment, the rats were inoculated by transoral intratracheal instillation with 5 X 10(7) CFU of P . aeruginosa obtained from a cystic fibrosis patient . Two weeks after inoculation, P . aeruginosa was cultured from the airways, and scanning and transmission electron microscopy showed bacilli adhering to or invading the injured airway epithelium . P . aeruginosa was present in tracheal and intrapulmonary tissue homogenates of 9% of the P . aeruginosa-inoculated control rats (n = 22) as compared with 61% of the 2-mg/ml (n = 18) and 65% of the 4-mg/ml (n = 20) HMPA-treated rats (P less than 0.05) . No dose-response relationship was found between 2 and 4 mg of HMPA per ml and colonization . Contamination of 47% of all of the rats with Mycoplasma pulmonis, as indicated by a positive enzyme-linked immunosorbent assay for immunoglobulin G, had no discernible significant effect on colonization by P . aeruginosa . These results indicate that colonization of the rat airway by P . aeruginosa can be achieved experimentally by treating the animals with HMPA . This research supports the hypothesis that colonization by P . aeruginosa may occur in airways where the ciliated epithelium has been injured and epithelial lesions exist. Infect Immun, 1983 Mar, 39(3), 1377 - 84 Protective immunization against chronic Pseudomonas aeruginosa pulmonary infection in rats; Klinger JD et al.; Rats were immunized systemically with various doses of the polyvalent Pseudomonas aeruginosa vaccine PEV-01 . After a series of two or three doses (25 to 50 micrograms each) at 8- to 11-day intervals, animals were challenged intratracheally by the agarose bead technique with a serotype 5 P . aeruginosa strain at periods of 9 to 42 days . Immunized animals developed circulating antibodies (primarily immunoglobulin M) against vaccine components at levels significantly higher than challenged, nonimmunized controls (P less than 0.005) . Eight to ten days postinfection, histological sections of lungs from immunized animals showed only minimal inflammation associated with infectious foci (agarose beads) as compared with the extensive pathological changes of airways and parenchyma seen in infected nonimmunized control animals . However, no significant reduction in bacterial numbers was observed . Such protection lasted at least 6 weeks after the final immunization . It is speculated that the vaccine may contain components of cell surface proteins and virulence exoproducts. Infect Immun, 1983 Mar, 39(3), 1275 - 9 Enhancement of Pseudomonas aeruginosa lung clearance after local immunization with a temperature-sensitive mutant; Sordelli DO et al.; We investigated the capacity of the temperature-sensitive mutant strain A/10/25 of Pseudomonas aeruginosa (ts-Psa) to induce enhancement of lung defenses against wild type P . aeruginosa (wt-Psa) . Mice of the DBA/2J inbred strain were immunized by aerosolization with a single dose of 2 x 10(5) to 4 x 10(5) CFU of ts-Psa and were challenged 7, 14, and 21 days later with wt-Psa . The uncleared bacteria ratio was determined 4 h after aerosol exposure; significant enhancement in lung clearance of wt-Psa (P less than 0.01) was evident as early as 7 days after immunization and detectable for at least 21 days . Aerosol immunization with Staphylococcus aureus did not enhance lung clearance of wt-Psa; however, slight but significant enhancement in S . aureus clearance was observed in mice immunized 7 days before with ts-Psa . No enhancement of S . aureus clearance was seen in ts-Psa immunized animals after 14 and 21 days . Analysis of the cell composition of lung lavage fluids revealed a transient cell response characterized by rapid increase in the absolute number of polymorphonuclear leukocytes, followed later by an increase in alveolar macrophages . The characteristics of lung lavages returned to base-line values 6 days after aerosol immunization, and a second exposure to a ts-Psa aerosol produced a response of similar magnitude and quality . We conclude that aerosol immunization with a temperature-sensitive mutant of P . aeruginosa enhances specific pulmonary defense mechanisms against the parental pathogen in mice. Infect Immun, 1983 Mar, 39(3), 1072 - 9 Protection against Pseudomonas aeruginosa infection in a murine burn wound sepsis model by passive transfer of antitoxin A, antielastase, and antilipopolysaccharide; Cryz SJ Jr et al.; The protective capacity of passively transferred immunoglobulin G (IgG) fractions from antitoxin (AT-IgG), antielastase (AE-IgG), and antilipopolysaccharide (ALPS-IgG) against Pseudomonas aeruginosa infection was evaluated in a murine burn wound sepsis model . Complete protection was afforded by homologous ALPS-IgG against intermediate challenge doses (10 50% lethal doses) of P . aeruginosa PA220, whereas AT-IgG and AE-IgG offered no significant protection (P less than 0.5) . The simultaneous transfer of AT-IgG or AE-IgG with ALPS-IgG gave no additional protection above that seen with ALPS-IgG alone . The transfer of ALPS-IgG did not dramatically alter bacterial multiplication in the skin at the site of infection . However, bacteremia and infection of the liver were prevented . In parallel experiments, AT-IgG or AE-IgG did not significantly alter either the course of the infection or the number of bacteria seen in the blood, liver, or skin when compared with controls . ALPS-IgG administered 24 h before infection, at the time of infection, or 4 h postinfection provided complete protection . Even when ALPS-IgG was transferred at a time when the infection was well established locally in the skin (8 h postinfection), highly significant protection (P greater than 0.999) was obtained . Protection afforded by ALPS-IgG was serotype specific . These results indicate that antibody to lipopolysaccharide is of critical importance for protection against P . aeruginosa challenge in a relevant animal model. Infect Immun, 1983 Mar, 39(3), 1067 - 71 Simple model for the study of Pseudomonas aeruginosa infections in leukopenic mice; Cryz SJ Jr et al.; A simple, reproducible model of fatal Pseudomonas aeruginosa sepsis in mice during immunosuppression was developed . Mice were rendered leukopenic (less than or equal to 800 leukocytes per mm3 of blood) for a period of 5 days by multiple injections of cyclophosphamide . Mice were challenged at the onset of leukopenia by instilling the bacteria onto a 0.5-mm incision made into the back . The mean lethal dose (LD50) for P . aeruginosa PA220 and M-2 was less than 20 bacteria . The mean time to death for these strains ranged from 46 to 59 h . Leukopenic mice were comparatively resistant when challenged with Klebsiella pneumoniae (LD50 = 1.5 x 10(6)) or Staphylococcus aureus (LD50 greater than 10(6)) . Infection with P . aeruginosa was characterized by rapid bacterial multiplication in the skin at the site of infection, producing ecthyma gangrenosum . Bacteremia and colonization of the liver were pronounced 21 h postinfection . This model should prove to be a useful tool for studying the pathogenesis of P . aeruginosa infections under immunosuppressed conditions. J Lab Clin Med, 1983 Mar, 101(3), 441 - 9 Experimental Pseudomonas aeruginosa sepsis: absence of synergy between ticarcillin and tobramycin; Chusid MJ et al.; An in vivo model of Pseudomonas aeruginosa sepsis was developed with normal and neutropenic guinea pigs injected intravenously with a strain of Pseudomonas demonstrated in vitro to be synergistically susceptible to ticarcillin and tobramycin . Therapy with ticarcillin, tobramycin, or a combination of the two starting 4 hr after intravenous injection of microorganisms was administered every 2 hr for periods up to 40 hr . Each therapy was associated with significant reductions in bacterial counts in blood, liver, spleen, and kidney compared with untreated animals . In no tissue in either normal or granulocytopenic animals did therapy with a combination of ticarcillin and tobramycin reduce bacterial counts significantly more effectively than did the better single antibiotic agent alone . These findings suggest that when ticarcillin and tobramycin are administered to animals at doses equivalent to therapeutic doses given in humans, a synergistic effect in reduction of bacterial counts in parenchymal organs and blood is not observed . These studies may help explain clinical reports in humans describing a lack of synergistic activity of combination antibiotic therapy in patients with Pseudomonas sepsis. J Bacteriol, 1983 Mar, 153(3), 1272 - 81 Genetic mapping of bra genes affecting branched-chain amino acid transport in Pseudomonas aeruginosa; Hoshino T et al.; Pseudomonas aeruginosa PAO mutants defective in the transport systems for branched-chain amino acids were isolated and characterized . Two mutations in strains selected for trifluoroleucine resistance, braA300 and braB307, were mapped in the met-9020-dcu-9108 and the nar-9011-puuC10 region, respectively . The mutation loci in strains selected for azaleucine resistance, braC310 and bra-311 through bra-314, were all located near the fla genes, with an order of region I fla-bra-region II fla . Strains with braA300 showed a marked reduction in the high-affinity branched-chain amino acid transport system (LIV-I) and a considerable decrease in the lower-affinity system (LIV-II) . Strains with braB307 were found to be defective in the LIV-II system . Strains selected for azaleucine resistance were all defective only in the LIV-I system and fell into three phenotypically distinct classes . Strains with braC310 produced a binding protein for leucine, isoleucine, valine, alanine, and threonine (LIVAT-BP) altered in binding ability, indicating that the braC gene is