| differential effects of ethanol on permissive versus nonpermissive macrophages infected with legionella pneumophila. | the effect of ethanol treatment was studied in terms of effect on permissive versus nonpermissive macrophages for growth of legionella pneumophila, which is an intracellular bacterium causing pneumonia in immunocompromised patients. it was found that ethanol treatment of permissive macrophages from l. pneumophila-susceptible a/j mice evinced a decrease in replication of the bacteria compared with nontreated infected macrophages. whereas there was more than a 100-fold increase in legionella growt ... | 1993 | 8516345 |
| the lipopolysaccharide of legionella pneumophila serogroup 1 (strain philadelphia 1): chemical structure and biological significance. | the lipopolysaccharide (lps, endotoxin) of legionella pneumophila serogroup 1 (philadelphia 1) exhibits peculiar chemical features which may account for its importance as a bacterial virulence factor. the o-chain of this lps constitutes a homopolymer of an unusual sugar, 5-acetamidino-7-acetamido-8-o-acetyl-3,5,7, 9-tetradeoxy-d-glycero-l-galacto-nonulosonic acid (legionaminic acid) of which about 10-75 residues are present. due to the lack of free hydroxyl groups, this homopolymer renders the c ... | 1995 | 8524918 |
| legionella pneumophila has two 60-kilodalton heat-shock proteins. | legionella pneumophila is a thermotolerant bacterium. to learn more about the thermal adaptation of this organism, we studied the properties of the legionella 60-kda heat-shock protein (mopa, groel-analog, htpb, lp-hsp60) in l. pneumophila and in an escherichia coli strain containing the cloned gene. lp-hsp60 was found in both cytosol and membrane fractions; however, lp-hsp60 in the membrane fraction of l. pneumophila was slightly larger than lp-hsp60 in the cytosol. in contrast, both membrane-a ... | 1995 | 8528004 |
| molecular cloning of a coxiella burnetii gene encoding a macrophage infectivity potentiator (mip) analogue. | the gene encoding a protein that reacted with antibodies specific for legionella pneumophila macrophage infectivity potentiator (lpmip) was cloned from coxiella burnetii, the obligate intracellular rickettsia that causes q fever in humans. nucleotide sequencing analysis revealed an orf encoding a gene product of 230 amino acids with a molecular mass of 25.5 kda and a predicted pi of 10.7. the predicted amino acid sequence from the orf shows similarity with mip/mip-like proteins of legionella (46 ... | 1995 | 8535514 |
| enzyme immunoassay for detection of antibodies against isolated flagella of legionella pneumophila. | flagella of legionella pneumophila serogroup 1, strain philadelphia (atcc 33152), were isolated and used as antigen to detect antibodies by enzyme immunoassay (eia) in sera of patients with significant titers against legionella as determined by the indirect immunofluorescence assay (ifa). healthy blood donors served as a control group. whereas the sera of blood donors were negative in both assays, sera of patients showed two patterns of reactivity. sera with elevated titers against legionella pn ... | 1995 | 8536723 |
| comparative susceptibility of legionella pneumophila and legionella longbeachae to 12 antimicrobial agents. | the in-vitro susceptibilities of 28 strains each of legionella pneumophila and legionella longbeachae to 12 antibiotics were compared by an agar dilution technique. a limited comparison with disc testing was also performed. most antibiotics were less active against l. longbeachae, although mics of erythromycin, ciprofloxacin and rifampicin suggest potential clinical utility. | 1995 | 8537269 |
| speculations on the influence of infecting phenotype on virulence and antibiotic susceptibility of legionella pneumophila. | it is not clear how legionella pneumophila, which is a ubiquitous aquatic organism not possessing a mammalian reservoir, evolved the ability to cause human disease. the unusual ecology of the organism may play an important role in the transmission and virulence of legionella infections. l. pneumophila can infect and kill specific species of free-living amoebae as well as multiplying as an intracellular parasite in human phagocytic cells. in nature l. pneumophila can survive and possibly replicat ... | 1995 | 8537286 |
| [azithromycin, pharmacodynamic evaluation in animal models]. | several experimental models have been used in order to evaluate the in vivo efficacy of azithromycin against numerous human pathogenic bacteria and parasites, including comparison between azithromycin and other antibiotics belonging or not to the macrolide family. using the experimental models, three major objectives can be distinguished: the comparative studies of the efficacy dose 50 (ed50) of azithromycin compared to other orally given antibiotics, the azithromycin efficacy in animal infected ... | 1995 | 8539074 |
| [role of macrolides in the treatment of respiratory tract infections in children]. | macrolides are antibiotics with high intracellular concentrations. they have a bacteriostatic activity but are also bactericides for concentrations five times greater than the minimal inhibitory concentration, concentrations in which they reach in the respiratory tract. they are usually active on streptococcus, neisseria, moraxella catarrhalis, listeria monocytogenes, bordetella pertussis, pasteurella multocida, chlamydia, mycoplasma pneumoniae, legionella pneumophila and helicobacter pylori. th ... | 1995 | 8548000 |
| pityriasis rosea gibert: detection of legionella micdadei antibodies in patients. | some epidemiological and clinical characteristics of pityriasis rosea gibert has led us to hypothesize that this disease may be the clinical manifestation of an infection caused by legionellas. we have thus tested the sera of 36 patients ill with pityriasis rosea and 19 controls for legionella pneumophila serogroup 1-6 and legionella micdadei antibodies. these, who had the same age and sex distribution as study patients, were receiving treatment for other diseases in the same ward. also tested w ... | 1995 | 8549715 |
| prevalence of legionella pneumophila serogroup 1 antibodies in blood donors. | the prevalence of anti-legionella pneumophila serogroup 1 antibodies in 777 blood donors of the turin area was determined by the indirect immunofluorescence assay (ifa) and by the microagglutination test (ma). low titers (ifa of 1/16 and ma of 1/8) were found in 0.3% of the subjects. a statistically significant difference was not observed by sex and by age for ifa titers, but was noted by sex for ma titers of > or = 1/4 (p < 0.05). the upper limit of normal titer was < 1/8 by ifa and < 1/4 by ma ... | 1995 | 8549718 |
| legionella pneumophila mutants that are defective for iron acquisition and assimilation and intracellular infection. | legionella pneumophila, a parasite of macrophages and protozoa, requires iron for optimal extracellular and intracellular growth. however, its mechanisms of iron acquisition remain uncharacterized. using mini-tn10 mutagenesis, we isolated 17 unique l. pneumophila strains which appeared to be defective for iron acquisition and assimilation. eleven of these mutants were both sensitive to the iron chelator ethylenediamine di(o-hydroxyphenylacetic acid) and resistant to streptonigrin, an antibiotic ... | 1996 | 8550218 |
| interaction of legionella pneumophila with acanthamoeba castellanii: uptake by coiling phagocytosis and inhibition of phagosome-lysosome fusion. | legionella pneumophila is a facultative intracellular parasite able to survive within both human monocytes and amoebae. we have demonstrated that processing of l. pneumophila by the free-living amoeba acanthamoeba castellanii shows many similarities to the processing of l. pneumophila by monocytes. these similarities include uptake of l. pneumophila by coiling phagocytosis and the subsequent confinement of l. pneumophila in a ribosome-studded phagosome. in addition, as in monocytes, inhibition o ... | 1996 | 8550225 |
| prevalence of pneumonia due to legionella pneumophila and mycoplasma pneumoniae in a population admitted to a department of internal medicine. | we studied 177 patients with pneumonia admitted to an internal medicine department over a period of 3 years to determine the incidence of two emerging pathogens, legionella pneumophila and mycoplasma pneumoniae. clinical, radiological and laboratory tests were performed and included blood cultures, serology, gram staining and sputum cultures. l. pneumophila was the agent involved in 9 patients (5.1%) and m. pneumoniae in 12 (6.8%). these prevalences were about in the middle of the range of previ ... | 1995 | 8552864 |
| decreased capacity of aged mice to produce interferon-gamma in legionella pneumophila infection. | we investigated the difference in natural resistance to legionella pneumophila infection between aged (18-20-month-old) and young (3-month-old) mice of ddy strain. aged mice were more susceptible to the bacterial infection than young mice; 50% lethal doses of l. pneumophila for aged and young mice were 2.2 x 10(7) and 8.5 x 10(7) colony forming units (cfu), respectively, after intraperitoneal injection of the bacteria. the bacterial burden in the livers was larger in aged than young mice after a ... | 1995 | 8569284 |
| legionnaires' disease and acute renal insufficiency: report of a case and review of the literature. | we report the case of a 73-year-old man, who developed acute renal failure in association with a legionella pneumophila serotype 1 pneumonia. renal biopsy revealed a tubulointerstitial nephritis. treatment with erythromycin, rifampicin and haemodialysis resulted in a clinical resolution of the pulmonary and renal syndromes. | 1995 | 8571732 |
| identification and characterization of an immunogenic outer membrane protein of campylobacter jejuni. | we cloned and expressed in escherichia coli a gene encoding an 18-kda outer membrane protein (omp18) from campylobacter jejuni atcc 29428. the nucleotide sequence of the gene encoding omp18 was determined, and an open reading frame of 165 amino acids was revealed. the amino acid sequence had the typical features of a leader sequence and a signal peptidase ii cleavage site at the n-terminal part of omp18. moreover, the sequence had a high degree of similarity to the peptidoglycan-associated outer ... | 1995 | 8576327 |
| comparison of legionella pneumophila isolates by arbitrarily primed pcr and pulsed-field gel electrophoresis: analysis from seven epidemic investigations. | arbitrarily primed pcr (ap-pcr) and pulsed-field gel electrophoresis (pfge) subtyping were applied to clinical and environmental isolates from seven unrelated outbreaks of legionnaires' disease. the patterns observed with each method matched patient isolates and the epidemiologically linked source of disease for each of the seven outbreaks. pfge allowed more discrimination among various isolates, although ap-pcr usually gave comparable results. with both methods, certain patterns appeared to pre ... | 1995 | 8576337 |
| temperature effects on legionella pneumophila killing by and multiplication in phagocytes of guinea pigs. | we examined the effects of temperature on the interaction between legionella pneumophila and phagocytes of guinea pigs. the body temperatures of guinea pigs infected with a sublethal dose (1.2 x 10(4) cfu) or a lethal dose (1.0 x 10(5) cfu) of l. pneumophila elevated from 38.4 +/- 0.15 c to 40.2 +/- 0.42 c or 40.3 +/- 0.62 c, respectively. the intracellular bacterial killing by and bacterial proliferation in the phagocytes were examined at 33, 37, 40, and 42 c, using in vitro culture systems of ... | 1995 | 8577277 |
| [legionella pneumophila serogroup 3 isolated from a patient of pneumonia developed after drowning in bathtub of a hot spring spa]. | a 71-year-old japanese female, was found unconscious by drawing, in a hot spring spa, at around noon of 20 october 1994. she recovered by emergency cardiopulmonary resuscitation, and admitted to the takinomiya general hospital, with adult respiratory distress syndrome (ards). although she recovered from ards within 4 days after her admission, she developed severe pneumonia accompanied with the second attack of ards. ordinary bacteriological culture of her respiratory specimens failed to yield an ... | 1995 | 8586887 |
| the reca protein as a model molecule for molecular systematic studies of bacteria: comparison of trees of recas and 16s rrnas from the same species. | the evolution of the reca protein was analyzed using molecular phylogenetic techniques. phylogenetic trees of all currently available complete reca proteins were inferred using multiple maximum parsimony and distance matrix methods. comparison and analysis of the trees reveal that the inferred relationships among these proteins are highly robust. the reca trees show consistent subdivisions corresponding to many of the major bacterial groups found in trees of other molecules including the alpha, ... | 1995 | 8587109 |
| azithromycin for treatment of community acquired pneumonia caused by legionella pneumophila: a retrospective study. | a clinical, retrospective and non-comparative study was undertaken to assess the clinical efficacy and tolerability of azithromycin in the treatment of community-acquired pneumonia caused by legionella pneumophila. a total of 16 patients with a serologically confirmed diagnosis of legionnaires' diseases were included. azithromycin was administered orally at a total dose of 1.5 g for either 3 or 5 days. all patients were no side-effects requiring discontinuation of the treatment. further increase ... | 1995 | 8588143 |
| natural resistance to infection with legionella pneumophila: chromosomal localization of the lgn1 susceptibility gene. | legionella pneumophila is a strict intracellular pathogen that replicates in the professional phagocytes of the human and guinea pig host. although murine macrophages from most inbred strains are non-permissive to intracellular replication of l. pneumophila, inflammatory macrophages from the mouse strain a/j are completely permissive to intracellular replication of this bacterium. this genetic difference is controlled by the expression of a single autosomal gene designated lgn1, with non-permiss ... | 1995 | 8589525 |
| intraphagocytic growth induces an antibiotic-resistant phenotype of legionella pneumophila. | the antimicrobial susceptibilities of legionella pneumophila isolates grown either in u937 human monocytic cells or in acanthamoeba polyphaga were studied after release from the host cells without further subculture. time-survival studies showed that exposure of l. pneumophila cells, gown exclusively in vitro, to 5 micrograms of rifampin per ml resulted in at least 99% killing after 6 h and no detectable survivors at 24 h. similar rates of killing were observed for in vitro-grown cells tested by ... | 1995 | 8593002 |
| outbreak of legionnaires' disease among cruise ship passengers exposed to a contaminated whirlpool spa. | outbreaks of travel-related legionnaires' disease present a public-health challenge since rapid, sensitive, and specific diagnostic tests are not widely used and because detection of clusters of disease among travellers is difficult. we report an outbreak of legionnaires' disease among cruise ship passengers that occurred in april, 1994, but that went unrecognised until july, 1994. | 1996 | 8596266 |
| differential nitric oxide (no) production by macrophages from mice and guinea pigs infected with virulent and avirulent legionella pneumophila serogroup 1. | l-arginine-dependent reactive nitrogen intermediates have been identified as macrophage cytotoxic effector molecules against intracellular pathogens. to determine its role, ex vivo production of no by peritoneal macrophages of c3h/hen mice and dunkin-hartley guinea pigs infected intraperitoneally with a virulent and isogenic avirulent legionella pneumophila serogroup 1 strain was compared with bacterial clearance from the lungs. while the virulent strain was cleared from mice lungs, the guinea p ... | 1996 | 8603533 |
| a paint incorporating silver to control mixed biofilms containing legionella pneumophila. | a three-stage chemostat containing a mixed consortium of microorganisms, including legionella pneumophila, was used to determine the suitability of a silver-containing paint to control biofouling in water systems. the paint was efficient in controlling total surface colonisation by heterotrophic microorganisms and growth of the pathogen over a 2-week period. biodiversity was limited in the presence of the silver paint and this was thought to help control l. pneumophila numbers. glass control til ... | 1995 | 8605075 |
| control of legionella pneumophila in a hospital water system by chlorine dioxide. | immuno-compromised patients are particularly susceptible to legionnaires' disease. after three cases of the disease occurred in a hospital, a continuous dosing regime using chlorine dioxide was initiated to replace chlorination of the water system. this study identified a number of factors which may have resulted in conditions that would encourage the growth of the water-borne pathogen legionella pneumophila. the residual chlorination was inadequate for microbial control at the taps furthest fro ... | 1995 | 8605076 |
| the legionella pneumophila hel locus encodes intracellularly induced homologs of heavy-metal ion transporters of alcaligenes spp. | we continued characterization of the legionella pneumophila hel locus. mutagenesis and dna sequencing identified three genes similar to the czc and cnr loci of alcaligenes eutrophus and the ncc locus of alcaligenes xylosoxidans. on the basis of their similarity to these loci, we designated the l. pneumophila genes helc, helb, and hela. mutations in the hel genes led to reduced cytopathicity towards u937 cells, although the mutant strains did not appear defective in other assays of virulence. tra ... | 1996 | 8613357 |
| de novo synthesis of legionella pneumophila antigens during intracellular growth in phagocytic cells. | legionella pneumophilia is a gram-negative rod which is able to multiply within phagocytic cells. the process of phagocytosis leads to a rapid environmental change that might require a coordinate regulation of gene expression to ensure intracellular survival. since there is little information on up- and downregulation of genes during the early phases of phagocytosis, we radiolabeled intracellular l. pneumophila at different times after phagocytosis by macrophages of the mono mac 6 cell line and ... | 1996 | 8613378 |
| spectrum of legionella species whose intracellular multiplication in murine macrophages is genetically controlled by lgn1. | we examined the intracellular growth of 20 strains within six species of legionella in thioglycolate-elicited peritoneal macrophages from a/j and c57bl/6 mice and a congenic strain derived from them (a.b lgn1). with the exception of legionella pneumophila togus-1 and bloomington-2, the intracellular growth of the 15 l. pneumophila strains tested was controlled by lgn1. however, the intracellular growth of five legionella species other than l. pneumophila was not under lgn1's control. | 1996 | 8613400 |
| absence of siderophore-like activity in legionella pneumophila supernatants. | conflicting reports have been given as to the existence of a legionella pneumophila siderophore. hence, we rigorously examined the reported siderophore-like activity using the chrome azurol s indicator. although chrome azurol s reactivity was detected in supernatants, control experiments indicate that it was due to cysteine in the media. when bacteria were cultured in media without cysteine, no siderophores were detected. | 1996 | 8613408 |
| legionellosis linked with a hotel car park--how many were infected? | an outbreak of legionellosis associated with a hotel in sydney, australia, and the subsequent epidemiological and environmental investigations are described. four cases of legionnaires' disease were notified to the public health unit. a cross-sectional study of 184 people who attended a seminar at the hotel was carried out. serological and questionnaire data were obtained for 152 (83%) of these. twenty-eight (18%) respondents reported symptoms compatible with legionellosis. thirty-three subjects ... | 1996 | 8620910 |
| nosocomial and community-acquired legionella pneumonia: clinical comparative analysis. | previous reports have suggested that nosocomial and community legionella pneumonia cases are similar. however, community and hospital characteristics, such as aquatic environment, antibiotic pressure (usage) and populations, are quite different, leading to the suspicion that legionella infection may differ in the two settings. univariate and multivariate analyses were performed to compare demographic data, risk factors, clinical, radiological and outcome data between 125 nosocomial and 33 commun ... | 1995 | 8620964 |
| construction of an alkaline phosphatase fusion-generating transposon, mtn10phoa. | we constructed a derivative of the mini-transposon mtn10 that generates translational fusions to the phoa gene from escherichia coli and carries the kmr determinant from tn5. this new transposon, mtn10phoa, is carried on a mobilizable plasmid with both selectable and counterselectable markers. the plasmid carrying mtn10phoa was introduced into legionella pneumophila. southern hybridization analysis indicated that the mtn10phoa insertions were randomly distributed. | 1996 | 8621078 |
| periplasmic copper-zinc superoxide dismutase of legionella pneumophila: role in stationary-phase survival. | copper-zinc superoxide dismutases (cuznsods) are infrequently found in bacteria although widespread in eukaryotes. legionella pneumophila, the causative organism of legionnaires' disease, is one of a small number of bacterial species that contain a cuznsod, residing in the periplasm, in addition to an iron sod (fesod) in their cytoplasm. to investigate cuznsod function, we purified the enzyme from wild-type l. pneumophila, obtained amino acid sequence data from isolated peptides, cloned and sequ ... | 1996 | 8626284 |
| the pseudomonas putida peptidoglycan-associated outer membrane lipoprotein is involved in maintenance of the integrity of the cell cell envelope. | pseudomonas putida 14g-3, a derivative of the natural soil inhabitant p. putida kt2440, exhibited a chromosomal insertion of a mini-tn5/'phoa transposon that resulted in reduced ability to colonize soil. in vitro characterization of p. putida 14g-3 revealed that it exhibited an altered cell morphology and envelope, as revealed by electron microscopy. the derived strain was sensitive to sodium dodecyl sulfate, deoxycholate, and edta, produced clumps when it reached high cell densities in the late ... | 1996 | 8626299 |
| comparison of multiplex pcr and culture for detection of legionellae in cooling tower water samples. | we compared multiplex polymerase chain reaction (pcr) and culture for detecting the presence of legionella pneumophila and legionella spp in cooling tower water samples. multiplex pcr was performed after phenol extraction of dna from the samples. the set of primers for the pcr assay involved the 5s rrna (legionella spp) and the mip (macrophage infectivity potentiator gene, specific for l. pneumophila) genes as target sequences for amplification. both the sensitivity and the specificity of the pc ... | 1995 | 8629056 |
| a legionella pneumophila gene that promotes hemin binding. | the ability to bind and utilize hemin is a trait common to many human pathogens. nevertheless, the relationship between legionella pneumophila, the agent of legionnaires' disease, and hemin has received little attention. thus, we explored the capacity of a virulent, serogroup 1 strain of l. pneumophila to bind hemin and use it as an iron source. hemin, but not protoporphyrin ix, restored bacterial growth in iron-limiting media, indicating that it can serve as an iron source for l. pneumophila. i ... | 1996 | 8641790 |
| in-vitro activity of levofloxacin against clinical isolates of legionella spp, its pharmacokinetics in guinea pigs, and use in experimental legionella pneumophila pneumonia. | the activities of levofloxacin and ofloxacin against 22 clinical legionella isolates was determined by microbroth dilution susceptibility testing. growth inhibition of two legionella pneumophila strains grown in guinea pig alveolar macrophages by levofloxacin, ofloxacin, or erythromycin was also determined. the drug concentrations required to inhibit 90% of strains tested was 0.032 mg/l for levofloxacin or ofloxacin, and was 0.016 mg/l for ciprofloxacin. bye alpha broth significantly inhibited t ... | 1996 | 8647752 |
| elevated levels of legionella pneumophila stress protein hsp60 early in infection of human monocytes and l929 cells correlate with virulence. | legionella pneumophila 2064 was selectively radiolabelled in mouse l929 cells and human monocytes to identify proteins expressed early in the course of infection. polypeptide profiles (sodium dodecyl sulfate-polyacrylamide gel electrophoresis and fluorography) of adherent or intracellular bacteria indicated that a 60-kda stress protein (hsp60) was preferentially synthesized. hsp60 synthesis was not induced by medium alone. the synthesis of many polypeptides, including omps (major outer membrane ... | 1996 | 8675295 |
| coinoculation with hartmannella vermiformis enhances replicative legionella pneumophila lung infection in a murine model of legionnaires' disease. | the effect of inhaled amoebae on the pathogenesis of legionnaires' disease was investigated in vivo. a/j mice, which are susceptible to replicative legionella pneumophila infections, were inoculated intratracheally with l. pneumophila (10(6) bacteria per mouse) or were coinoculated with l. pneumophila (10(6) bacteria per mouse) and hartmannella vermiformis (10(6) amoebae per mouse). the effect of coinoculation with h. vermiformis on bacterial clearance, histopathology, cellular recruitment into ... | 1996 | 8698466 |
| identification of legionella pneumophila mutants that have aberrant intracellular fates. | after uptake by macrophages, legionella pneumiophila evades phagosome-lysosome fusion and replicates in a compartment associated with the endoplasmic reticulum. a collection of bacterial mutants defective for growth in macrophages were isolated, and the intracellular fate of each mutant strain was analyzed by fluorescence microscopy. to measure intracellular replication, bacteria inside macrophages were stained with the dna dye 4',6-diamidino-2-phenylindole (dapi). evasion of the endocytic pathw ... | 1996 | 8698483 |
| isolation and amino acid sequence of a new 22-kda fkbp-like peptidyl-prolyl cis/trans-isomerase of escherichia coli. similarity to mip-like proteins of pathogenic bacteria. | we identified a periplasmic peptidyl-prolyl cis/trans-isomerase (ppiase) of the (fk506-binding protein (fkbp) type in escherichia coli (fk506 represents a natural peptidomacrolide containing an acylated pipecolic acid residue). after purification to homogeneity, its complete amino acid sequence was determined by a combination of edman degradation and electrospray mass spectrometry of the authentic protein and peptides generated by proteolysis. the molecular mass calculated from the amino acid se ... | 1996 | 8703024 |
| [acute community-acquired pneumonia of moderate and grave severity investigated by bronchoscopy. analysis of 193 cases hospitalized in a general hospital]. | between february 1989 and june 1994 193 cases of acute community acquired pneumonia (pac) which were of intermediate or great severity were admitted to two hospitals in the south west of france. these patients were explored using bronchofibroscopy (fb) with a protected brush (bp) and alveolar microlavage (mlba) and quantitative cultures were performed, also there were other specimens taken in a regular fashion. the percentage of positive examinations was 60% for brushings (bp), 59% for mlba and ... | 1996 | 8711237 |
| effects of interferon-alpha, beta, and gamma on the function of differentiated leukemic hl-60 cells induced by 1,25-dihydroxyvitamin d3. | the differentiation of hl-60, a human leukemic cell line, into monocyte-like cells (d3-hl-60 cells) is induced by 1,25-dihydroxyvitamin d3 (d3). we examined the effects of interferon (ifn) treatment of d3-hl-60 cells on the expression of cell surface antigens, the phagocytic activity for fluorescent beads, production of oxygen radicals, and intracellular growth of legionella pneumophila. activation of d3-hl-60 cells with ifn-gamma, beta, and alpha for 24 h significantly increased expression of c ... | 1996 | 8727074 |
| [virulent factors of legionella pneumophila and their uses in molecular epidemiology]. | | 1995 | 8728961 |
| legionnaires' disease--a potential hazard of rationalisation. | the cases of two elderly patients who complained of general malaise after they had undergone ward transfer (due to rationalisation of the rehabilitation service) are discussed. both were pyrexial and had signs of pneumonic consolidation. subsequent investigation revealed that their symptoms were due to infection with legionella pneumophila. their cases highlight the problems associated with ward closures and the hazards of stagnant water. | 1996 | 8731649 |
| comparison of binax legionella urinary antigen eia kit with binax ria urinary antigen kit for detection of legionella pneumophila serogroup 1 antigen. | the legionella urinary antigen eia kit (binax, portland, maine) was compared with the equate ria legionella urinary antigen kit (binax) for its ability to detect the presence of urinary antigens to legionella pneumophila serogroup 1. urine specimens from patients without legionnaires' disease (n = 33) were negative by both methods (specificity, 100%). twenty (77%) of 26 urine specimens from patients with legionnaires' disease positive by the radioimmunoassay kit were also positive by the enzyme ... | 1996 | 8735125 |
| molecular typing of nosocomial strains of legionella pneumophila by arbitrarily primed pcr. | arbitrarily primed pcr with two different primers was compared with ribotyping and monoclonal antibody analysis for typing legionella strains. applied to 11 epidemiologically unrelated strains, arbitrarily primed pcr resulted in an index of discrimination of 100% with both primers. it was found able to identify an epidemic clone of legionella pneumophila serogroup 1 that was isolated from both patients and a hot water circuit of the same hospital. | 1996 | 8735131 |
| value of routine microbial investigation in community-acquired pneumonia treated in a tertiary care center. | the study was conducted at a tertiary care and teaching hospital with about 200 beds for internal medicine. the objective was to determine the diagnostic yield and value in directing antibiotic therapy of a routine microbial approach in patients with community-acquired pneumonia referred to a tertiary care center. we studied 93 episodes in a retrospective study. 69/93 (74%) cases were treated with at least one empirical antibiotic therapy prior to admission. microbial investigation was performed ... | 1996 | 8739487 |
| legionella pneumophila invasion of mononuclear phagocytes. | | 1996 | 8742248 |
| field inversion gel electrophoretic analysis of legionella pneumophila strains associated with nosocomial legionellosis in children. | two nosocomial cases of legionnaires' disease occurred in children. legionella pneumophila serogroup 1 was isolated from both patients and 30 of 39 plumbing system sites in the hospital. the patient and hospital environmental isolates yielded identical field inversion gel electrophoretic patterns which differed from patterns observed with epidemiologically unrelated strains. | 1996 | 8748296 |
| antimicrobial chemotherapy for legionnaires' disease: a review. | controlled trials of antimicrobial chemotherapy for legionnaires' disease have not been performed, although erythromycin and tetracycline appear to be effective therapies. laboratory data indicate that the activities of the fluoroquinolone and newer macrolide/azalide agents against legionella pneumophila are superior to that of erythromycin, and case reports substantiate that the activities of these agents are at least equal. results of clinical treatment with and laboratory testing of macrolide ... | 1995 | 8749675 |
| prevalence of legionella pneumophila infection in children and its role in pediatric community-acquired atypical pneumonia. | the infection status of legionella pneumophila in children and its role in pediatric community-acquired pneumonia were investigated. because exposure to legionella pneumophila may be highly variable and there has been no unanimously agreed-upon cut-off values in previous seroprevalence studies, 60 serum samples collected from infants aged 12 to 18 months were examined using immunofluorescence antibody test to determine the cut-off titer which represents past legionella pneumophila infection. an ... | 1996 | 8755173 |
| induction of cytokine granulocyte-macrophage colony-stimulating factor and chemokine macrophage inflammatory protein 2 mrnas in macrophages by legionella pneumophila or salmonella typhimurium attachment requires different ligand-receptor systems. | the attachment of bacteria to macrophages is mediated by different ligands and receptors and induces various intracellular molecular responses. in the present study, induction of cytokines and chemokines, especially granulocyte-macrophage colony-stimulating factor (gm-csf) and macrophage inflammatory protein 2 (mip-2), was examined, following bacterial attachment, with regard to the ligand-receptor systems involved. attachment of legionella pneumophila or salmonella typhimurium to cultured mouse ... | 1996 | 8757834 |
| roles for tumor necrosis factor alpha and nitric oxide in resistance of rat alveolar macrophages to legionella pneumophila. | legionella pneumophila is an intracellular parasite of alveolar macrophages, and recovery from legionellosis is associated with activation of alveolar macrophages to resist intracellular bacterial replication. gamma interferon (ifn-gamma) is known to activate alveolar macrophages to suppress l. pneumophila, but the role of macrophage-derived cytokines in modulating alveolar macrophage resistance is unknown. to test the hypothesis that macrophage-derived mediators contribute to the resistance of ... | 1996 | 8757859 |
| serotyping, ribotyping, pcr-mediated ribosomal 16s-23s spacer analysis and arbitrarily primed pcr for epidemiological studies on legionella pneumophila. | fifty clinical and environmental isolates of legionella pneumophila were typed serologically and by dna fingerprinting using arbitrarily primed polymerase chain reaction (ap-pcr). furthermore, variability in and around ribosomal operons was assessed by conventional ribotyping and pcr-mediated amplification of the spacer region separating the 16s and 23s genes. it appears that serotyping suffers from low resolution capabilities, and ribotyping and spacer pcr display intermediate resolving capabil ... | 1996 | 8763626 |
| species-specific detection of legionella using polymerase chain reaction and reverse dot-blotting. | legionella pneumophila and some other legionella species are capable of causing legionnaire's disease, a potentially fatal pneumonia. the identification of legionellae by standard laboratory techniques such as culture is difficult and time consuming. in the present work, the dna sequence of the 23s-5s spacer region was determined for 43 legionella isolates, and the sequence information was used to develop a species-specific detection system using pcr and reverse dot-blotting which employs just o ... | 1996 | 8764471 |
| [atypical pneumonia caused by legionella pneumophila. report of a second case in mexico]. | an outbreak of pneumonia that caused 34 deaths among 221 legionnaires was reported in 1977 at the american legion convention in philadelphia. the causative agent was eventually recognized and named legionella pneumophila. legionellosis is a worldwide disease, but in mexico there is only one report of legionnaires' disease, possibly because it is not thought of as a cause of community-acquired pneumonia. we report a previously healthy patient who required admittance to our icu with community-acqu ... | 1995 | 8768605 |
| effect of heat flushing on the concentrations of legionella pneumophila and other heterotrophic microbes in hot water systems of apartment buildings. | the decontamination of legionella pneumophila and other heterotrophic microbes by heat flushing in four legionellae-positive hot water systems was studied. before the decontamination procedure, the concentration of legionellae varied from 3.0 x 10(3) to 3.5 x 10(5) cfu/l and the hot water temperature from 43.6 to 51.5 degrees c. during the contamination the temperature was raised to 60-70 degrees c. all taps and showers were cleaned from sediments and flushed with hot water twice a day for sever ... | 1996 | 8776852 |
| the phagosome containing legionella pneumophila within the protozoan hartmannella vermiformis is surrounded by the rough endoplasmic reticulum. | legionella pneumophila is an intracellular parasite of protozoa and human phagocytes. to examine adaptation of this bacterium to parasitize protozoa, the sequence of events of the intracellular infection of the amoeba hartmannella vermiformis was examined. the previously described uptake phenomenon of coiling phagocytosis by human monocytes was not detected. a 1 h postinfection with wild-type strain aa100, mitochondria were observed within the vicinity of the phagosome. at 2.5 h postinfection, n ... | 1996 | 8787400 |
| cannabinoids and immunity to legionella pneumophila infection. | | 1996 | 8787650 |
| [subserogrouping of 49 legionella pneumophila serogroup 1 strains with monoclonal antibodies by slide latex agglutination method and its usefulness for epidemiologic study]. | legionella pneumophila serogroup (sg) 1 has been known as a most frequent and important causative bacteria of legionella pneumonia. it was reported that antigenicity of the serogroup was composed by numerous antigenic factors. to study antigenic factor formula of japanese isolates from both clinical and environmental sources together with philadelphia 1 strain, we examined slide latex agglutination system with monoclonal antibodies for subsergorouping. philadelphia 1 and gifu10102 strain (enviro ... | 1996 | 8797301 |
| increased plasma adenosine deaminase activity in the early phase of legionella pneumophila infection in guinea pigs. | we measured adenosine deaminase (ada) activity in a guinea pig model of legionella pneumophila infection. female hartley guinea pigs were inoculated intraperitoneally with one-quarter of the ld50 dose of l. pneumophila philadelphia-1 strain. control groups were inoculated with clinical isolates of staphylococcus aureus, streptococcus pneumoniae, haemophilus influenzae or klebsiella pneumoniae. each group consisted of 5 animals. ada activity in plasma was assayed calorimetrically before and at va ... | 1996 | 8804974 |
| il-10 enhances the growth of legionella pneumophila in human mononuclear phagocytes and reverses the protective effect of ifn-gamma: differential responses of blood monocytes and alveolar macrophages. | legionella pneumophila is a facultative intracellular pathogen that parasitizes human alveolar macrophages and blood monocytes recruited to the lungs. the inhibitory cytokines il-10, tgf-beta, and il-4 generally deactivate macrophages and permit enhanced microbial growth in some models of intracellular infection, but their effects on human alveolar macrophages are unknown. we hypothesized that inhibitory cytokines could facilitate the infection of human alveolar macrophages and monocytes by viru ... | 1996 | 8805654 |
| immunoregulatory role of nitric oxide in legionella pneumophila-infected macrophages. | nitric oxide (no) is an intercellular messenger molecule produced by a variety of cells, including macrophages. however, the role of no in infection, especially its immunological role, is poorly understood. in the present study, the role of no in legionella pneumophila-infected macrophages was examined. whereas infection of mouse macrophages in vitro with l. pneumophila did not induce detectable no, when the macrophages were primed with interferon-gamma (ifn-gamma), the treated macrophages marke ... | 1996 | 8806792 |
| typing of legionella pneumophila serogroup 1 isolates by degenerate (d-)rapd fingerprinting. | a new method to identify clonal strains of pathogenic bacteria has been developed recently in this laboratory. the method utilizes degenerate random amplified polymorphic dna primers (d-rapd) to amplify random fragments in crude bacterial lysates, generating reproducible dna banding profiles or fingerprints. we use this method to type outbreak and non-outbreak isolates of legionella pneumophila serogroup 1 from four hospitals near to, and affiliated with the university of pittsburgh medical cent ... | 1995 | 8808311 |
| [prospective study of the etiology of community-acquired pneumonia among patients in a general hospital]. | we prospectively studied the etiology of community-acquired pneumonia among all patients who were admitted to our hospital from july 1994 to june 1995. tests for microbial pathogens including chlamydia spp. and legionella spp. were performed and diagnoses were made with strict criteria. a total 110 patients with 111 episodes of pneumonia were evaluated, and a pathogen was identified in 61 episodes (55%). the most common pathogen was streptococcus pneumoniae (18%), followed by haemophilus influen ... | 1996 | 8810756 |
| differences in immune functions between human t-lymphotropic virus type i carriers and patients with adult t-cell leukemia/lymphoma. | a variety of immunologic tests were compared between human t-lymphotropic virus type i (htlv-i) carriers and patients with adult t-cell leukemia/lymphoma (atl). the mitogenic responses of the lymphocytes to concanavalin a and phytohemagglutinin were depressed in the atl patients but not in the carriers, while the response to pokeweed mitogen in the carriers and atl patients was depressed compared to the htlv-i-seronegative controls. a positive tuberculin reaction in the carriers was as frequent ... | 1996 | 8811055 |
| characterization of an oprl null mutant of pseudomonas putida. | a pseudomonas putida oprl null mutant was generated with reverse genetics by using an in vitro-truncated oprl::xyle construct and in vivo allelic exchange. the nature of the mutation introduced in p. putida was confirmed by southern blotting. western blots (immunoblots) of peptidoglycan-associated proteins revealed that the oprl protein was not made in the mutant strain, whereas it was detectable as a 19-kda band in protein preparations of the wild-type strain. the p. putida oprl, mutant exhibit ... | 1996 | 8824639 |
| the molecular ecology of legionellae. | legionella pneumophila is the most highly characterized member of a genus of bacteria that survive as intracellular parasites of freshwater protozoa. these bacteria can also multiply intracellularly in human phagocytic cells and cause respiratory disease in humans. comparison of the invasive strategies of l. pneumophila in mammalian and protozoan cells and study of the interactions between legionella and protozoa should prove useful in development of strategies for the prevention of legionellosi ... | 1996 | 8829338 |
| insufficient evidence of synergistic effect of levofloxacin and rifampin against legionella pneumophila. | | 1996 | 8834916 |
| community outbreak of legionnaires' disease: an investigation confirming the potential for cooling towers to transmit legionella species. | in august and september 1993, we investigated an outbreak of legionnaires' disease in fall river, massachusetts, that involved 11 persons; the attack rate was highest in flint, a community of fall river. all cases were infected with legionella pneumophila serogroup 1 (lp-1). a case-control study revealed that cases were more likely than matched controls to have visited sites in neighborhood a of flint. environmental sampling in flint found that four of nine aerosol-producing devices sampled cont ... | 1996 | 8838181 |
| legionella pneumophila infection in taiwan: a preliminary report. | legionella pneumophila infection has been recognized as an important cause of pneumonia. however, epidemiologic baseline data about the occurrence of legionella-related pneumonia and the distribution of legionellae in aquatic environments are still not available in taiwan. a survey conducted by the national institute of preventive medicine found that 8.6% of 487 pneumonia patients studied were positive for the l. pneumophila serologic test (indirect fluorescent test, ifa) and 32.0% of the 25 wat ... | 1996 | 8840755 |
| false-positive legionella titres in routine clinical serology testing detected by absorption with campylobacter: implications for the serological diagnosis of legionnaires' disease. | a simple absorption step using blocking fluid prepared from a selected campylobacter strain was introduced in parallel with routine legionella serology tests. over 12 months, 2716 patients were tested for legionella antibodies by the indirect fluorescent antibody test of whom 58 (2.1%) had a positive titre (> or = 16) in one or more sera. campylobacter blocking fluid significantly reduced the legionella titres in 17 of these patients (29%) including four patients with diagnostic serology results ... | 1996 | 8852547 |
| hot tub legionellosis. | legionella pneumophila is the cause of legionnaires' disease, and pontiac fever, an influenza-like condition without pneumonia. we present a case of pontiac fever after exposure to a hot tub contaminated with l pneumophila. a 37 y/o wf presented to the office with acute onset of sore throat, fever, headache, and myalgia. patient was hospitalized 3 days later because of worsening shortness of air. chest x-ray was normal. patient was treated with 2 days of iv erythromycin and was discharged home o ... | 1996 | 8855593 |
| live tularemia vaccine confers protection against lethal legionella and listeria infections in experimental animals. | the efficacy of a live francisella tularensis vaccine strain to cause nonspecific immunity toward experimental legionellosis and listeriosis was studied. immunisation with tularemia vaccine protected over 80% and 17% of experimental animals against subsequent lethal challenge with legionella pneumophila and listeria monocytogenes, respectively. the protection was maximal during the first month following immunisation and declined thereafter. in order to delineate the immunostimulatory moieties of ... | 1996 | 8861031 |
| detection of legionella pneumophila serogroup 1 antigen in nonconcentrated urine and urine concentrated by selective ultrafiltration. | we evaluated a commercially available radioimmunoassay technique for detecting the soluble antigen of legionella pneumophila serogroup 1 using concentrated and nonconcentrated urine. concentration was achieved by selective ultrafiltration. the sensitivity of the technique was 60.9% for nonconcentrated urine and 80.4% for concentrated samples, with 100% specificity in both cases. | 1996 | 8862616 |
| effects of different surfactant preparations on bacterial growth in vitro. | several lines of evidence suggest that surfactant and surfactant proteins may have direct effects on inhaled bacteria and are able to interact with lung defence mechanisms in many ways. we examined the effect of three different surfactant preparations (alveofact, survanta and exosurf) approved for treatment of the infant respiratory distress syndrome on different strains of escherichia coli, staphylococcus aureus, staphylococcus epidermidis and streptococcus agalactiae which are important neonat ... | 1996 | 8864432 |
| the use of differential display-pcr to isolate and characterize a legionella pneumophila locus induced during the intracellular infection of macrophages. | the differential display (dd)-pcr technique has been modified to identify prokaryotic cdna fragments that are differentially induced by facultative intracellular bacteria in response to the intracellular environment of eukaryotic cells. several dd-pcr fragments identified from the intracellular bacterium legionella pneumophila were induced at 4 h post-infection of the u937 macrophage-like cells. from these, a 700 bp fragment was cloned and sequenced. neither the dna sequence nor the predicted pr ... | 1996 | 8866478 |
| assessment of enzyme immunoassay versus radioimmunoassay for detection of legionella pneumophila serogroup 1 antigen in frozen urine specimens. | an enzyme immunoassay (eia) was compared with a radioimmunoassay (ria) for detection of legionella pneumophila serogroup 1 antigen in 37 frozen urine samples. among 18 samples positive by the ria at the time of collection, 50% (9 of 18) of stored specimens retained positivity when retested by the ria whereas 78% (14 of 18) of stored specimens retained positivity when retested by the eia (p < 0.02). a false-negative result occurred after storage for 5 months or less if the original ria result sho ... | 1996 | 8880539 |
| azithromycin. a review of its pharmacological properties and use as 3-day therapy in respiratory tract infections. | the azalide antibacterial agent azithromycin is a semisynthetic acid-stable erythromycin derivative with an expanded spectrum of activity and improved tissue pharmacokinetic characteristics relative to erythromycin. the drug is noted for its activity against some gram-negative organisms associated with respiratory tract infections, particularly haemophilus influenzae. azithromycin has similar activity to other macrolides against streptococcus pneumoniae and moraxella catarrhalis, and is active a ... | 1996 | 8882383 |
| an international investigation of an outbreak of legionnaires disease among uk and french tourists. | five cases of legionnaires disease and one death were associated with four members of a tour group from the united kingdom (uk) and one french tourist who all visited spain in the spring of 1993. the uk group stayed at four hotels, one of which was also used by the french tourist. phenotypic and genotypic comparison of isolates of legionella pneumophila obtained from one of the uk cases and the french patient demonstrated that they were indistinguishable from each other and from environmental is ... | 1996 | 8884186 |
| nosocomial pneumonia in mechanically ventilated adult patients: epidemiology and prevention in 1996. | mechanically ventilated patients have a higher incidence of pneumonia and mortality than do nonventilated patients. ventilator-associated pneumonia (vap) is diagnosed clinically, by bronchoscopy or "blind" bronchoalveolar lavage (bal) or protected specimen brush (psb), and by quantitative endobronchial aspirates (qea). vap is usually caused by bacteria, but legionella pneumophila, mycobacterium tuberculosis, viruses, and fungi are also potential pathogens. bacteria causing nosocomial pneumonia m ... | 1996 | 8885061 |
| typing of legionella pneumophila strains isolated in greece by arbitrarily-primed pcr. | genomic fingerprints from dna of fifteen environmental and clinical strains of legionella pneumophila serogroup 1, isolated from diverse geographic areas of greece, during the period 1986 to 1994, were generated with arbitrarily-primed polymerase chain reaction (ap-pcr) in order to use the discriminatory power of two arbitrary primers, bg2 and m13 forward to clarify the relationship among the fifteen isolates. both primers were found to have the ability to discriminate strains of the same serogr ... | 1996 | 8891350 |
| growth, respiration and survival of legionella pneumophila at high temperatures. | the optimum temperature for multiplication of legionella strains in culture media is around 37 degrees c. the effect of high temperatures on the growth of strains isolated from various environments is poorly known. we studied the growth (cell multiplication, respiration) of clinical and environmental legionella pneumophila strains in liquid media at intervals of 0.5 degrees c in the temperature range from 41.6 to 51.6 degrees c using a temperature gradient incubator. cell multiplication and co2 ... | 1996 | 8896348 |
| nosocomial legionnaires' disease caused by legionella pneumophila serogroup 5: laboratory and epidemiologic implications. | environmental monitoring and clinical surveillance for legionella species were done for 12 months as recommended by the allegheny county health department (pittsburgh). the water system of a hospital was found to be colonized with legionella pneumophila serogroup 5. three patients with nosocomial l. pneumophila serogroup 5 disease were subsequently diagnosed after laboratory tests for legionellae were made available for all patients with nosocomial pneumonia. all serogroup 5 isolates from the ho ... | 1996 | 8896520 |
| a cyclophilin-like peptidyl-prolyl cis/trans isomerase from legionella pneumophila--characterization, molecular cloning and overexpression. | legionella pneumophila is the causative agent of a severe form of pneumonia in humans (legionnaires' disease). a major virulence factor, the mip protein (fk506-binding protein, fkbp25mem), belongs to the enzyme family of peptidyl-prolyl cis/trans isomerases (pplases). here we show that l. pneumophila philadelphia i possesses an additional cytoplasmic pplase at a level of enzyme activity comparable to that of fkbp25mem. the n-terminal amino acid sequence of the purified protein was obtained by ed ... | 1996 | 8898384 |
| in vitro activity of macrolides against intracellular legionella pneumophila. | the antibacterial effects of clarithromycin, azithromycin, and erythromycin were determined against five strains of legionella pneumophila including l. pneumophila atcc 33823 and four clinical isolates. extracellular minimum inhibitory concentrations (mics) and mbcs were determined by a microdilution method. clarithromycin was the most active drug (mic < or = 0.015-0.06), followed by azithromycin (mic 0.03-0.12) and erythromycin (mic 0.06-0.25). the antibacterial effect of these macrolides was t ... | 1996 | 8902407 |
| detection of rrna from four respiratory pathogens using an automated q beta replicase assay. | ribosomal rna targets from mycobacterium avium complex (23s), mycoplasma pneumoniae (16s), pneumocystis carinii (18s) and legionella pneumophila (16s) were detected in four separate assays on a model automated q-beta amplification instrument. sandwich hybridization, reversible target capture, detector probe amplification and fluorescent signal detection occurred in closed, disposable packs at 38 degrees c. packs were injected with 0.5 ml samples in 3.06 m guanidine thiocyanate. ten samples per r ... | 1996 | 8910891 |
| community-acquired pneumonia in chronic obstructive pulmonary disease: a spanish multicenter study. | community-acquired pneumonia (cap) is an infectious illness that frequently motivates hospital admission when comorbid conditions are present. however, the epidemiology of cap in relation to the underlying disease of the patients is not well known. we performed a prospective multicenter study with the aim of assessing the clinical characteristics, etiology, and outcome of chronic obstructive pulmonary disease (copd) patients with cap. between october 1992 and december 1994 we studied 124 copd pa ... | 1996 | 8912764 |
| presence of legionella spp. in thermal springs of the campania region of south italy. | water samples from 66 thermal springs in the campania region of south italy were cultured for legionella spp., pseudomonas aeruginosa, and indicators of faecal pollution. the temperature of the sources ranged from 21 degrees c to 59.5 degrees c. legionella pneumophila, serogroup 7-10, was isolated from two out of 60 sources on the island of ischia and legionella dumoffii from one mainland source. the temperatures of these sources were 35.2 degrees c, 48.2 degrees c, and 52.0 degrees c respective ... | 1996 | 8914132 |
| spontaneous rupture of the spleen associated with pneumonia. | spontaneous rupture of the spleen is a rare and life-threatening complication of bacterial pneumonia, only six properly documented cases having been reported to date. a case of spontaneous splenic rupture associated with pneumonia caused by legionella pneumophila is presented, together with a review of the literature. most of the patients were aged over 50, but none had predisposing conditions. left lung involvement predominated. legionellosis and q fever were the most frequent etiologic diagnos ... | 1996 | 8922573 |
| a 28 kda major immunogen of chlamydia psittaci shares identity with mip proteins of legionella spp. and chlamydia trachomatis-cloning and characterization of the c. psittaci mip-like gene. | chlamydia psittaci strain guinea-pig inclusion conjunctivitis (gpic) produces a self-limiting ocular infection of guinea-pigs, and this condition is a representative animal model of ocular chlamydial disease. convalescent guinea-pigs, which are resistant to reinfection, produce antibodies to several elementary-body proteins, including an uncharacterized antigen of 28 kda. convalescent guinea-pig sera were used to identify, from a lambda expression library, two overlapping gpic genomic clones tha ... | 1996 | 8936321 |
| structural study of a highly o-acetylated core of legionella pneumophila serogroup 1 lipopolysaccharide. | a core oligosaccharide was obtained after mild acid degradation of legionella pneumophila serogroup 1 lipopolysaccharide (lps). on the basis of chemical, glc-ms, 1h, and 13c nmr spectroscopic data, it was found that the oligosaccharide obtained is a highly o-acetylated heptasaccharide having the following structure: [formula: see text] where kdo is 3-deoxy-d-manno-octulosonic acid and quinac is 2-acetamido-2,6-dideoxyglucose. in the lps, the o-specific polysaccharide chain is linked to position ... | 1996 | 8938377 |
| humoral immunity and regulation of intrapulmonary growth of legionella pneumophila in the immunocompetent host. | the potential role of humoral immunity in regulating intrapulmonary growth of legionella pneumophila in the immunocompetent host was investigated using a murine model of legionnaires' disease. intratracheal inoculation of a/j mice with a virulent strain of l. pneumophila (10(6) bacteria per mouse) resulted in the recruitment of b lymphocytes into the lung and the development of anti-l. pneumophila ab. opsonization of l. pneumophila in vitro with anti-l. pneumophila-specific mab resulted in a sig ... | 1996 | 8943407 |
| legionella pneumophila heat-shock protein-induced increase of interleukin-1 beta mrna involves protein kinase c signalling in macrophages. | heat-shock proteins (hsp) are chaperon molecules important in protein folding and assembly. furthermore, they may have functions in immunoregulatory processes, like t-cell stimulation and antigen presentation, which are not yet fully understood. it has been shown that several hsp of various species and family derivations modulate functions in macrophage immunity by directly increasing cytokine production. in the present study we showed that the 60,000 mw hsp of legionella pneumophila (lp-hsp 60) ... | 1996 | 8943727 |
| evidence for apoptosis of human macrophage-like hl-60 cells by legionella pneumophila infection. | legionella pneumophila, the causative agent of legionnaires' disease and pontiac fever, replicates within and eventually kills human macrophages. in this study, we show that l. pneumophila is cytotoxic to hl-60 cells, a macrophage-like cell line. we demonstrate that cell death mediated by l. pneumophila occurred at least in part through apoptosis, as shown by changes in nuclear morphology, an increase in the proportion of fragmented host cell dna, and the typical ladder pattern of dna fragmentat ... | 1996 | 8945524 |
| effector mechanisms responsible for gamma interferon-mediated host resistance to legionella pneumophila lung infection: the role of endogenous nitric oxide differs in susceptible and resistant murine hosts. | to facilitate identification of the effector mechanism(s) responsible for gamma interferon (ifn-gamma)-mediated host resistance to legionella pneumophila, a murine model of legionellosis in balb/c mice with a targeted disruption in the ifn-gamma gene (gamma knockout [gko] mice) was developed. immunocompetent balb/c mice and gko mice were inoculated intratracheally with virulent l. pneumophila (10(6) bacteria per mouse), and bacterial clearance and the pulmonary inflammatory response were assesse ... | 1996 | 8945559 |