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hot water systems as sources of legionella pneumophila in hospital and nonhospital plumbing fixtures.samples obtained from plumbing systems of hospitals, nonhospital institutions and homes were cultured for legionella spp. by plating the samples directly on a selective medium. swab samples were taken from the inner surfaces of faucet assemblies (aerators, spouts, and valve seats), showerheads, and shower pipes. water and sediment were collected from the bottom of hot-water tanks. legionella pneumophila serogroups 1, 5, and 6 were recovered from plumbing fixtures of the hospitals and nonhospital ...19827103477
acanthamoebiasis and immunosuppression. case report.immunosuppression and debilitating illnesses are occasionally associated with multifocal brain lesions of acanthamoebiasis, an encephalitis distinct from the acute, water-sport related meningoencephalitis caused by naegleria fowler. a 38-year-old man with a renal transplant two and one-half years before his final illness developed pneumonia due to legionella micdadei. candida albicans was isolated from sputum and cytomegalovirus was found in lung and liver biopsies. he had continuous corticoster ...19827108568
lytic activity of bdellovibrio bacteriovorus against bacteria of the family legionellaceae.a lytic activity of bdellovibrio bacteriovorus strains 6-5-s and 12 was found to be present, against representatives of three legionella species: legionella pneumophila-strains knoxville 1 (serogroup 1), togus 1 (serogroup 2), bloomington 2 (serogroup 3) and los angeles 1 (serogroup 4); legionella micdadei-strain tatlock; legionella bozemanii-strain wiga, as well as against strains of legionella pneumophila isolated in bulgaria-draginovo 1, 2, 3-belonging to serogroup 1. it is suggested that b. ...19827124158
legionella micdadei pneumonia. historical perspective of a new pneumonia. 19827140393
legionella micdadei (pittsburgh pneumonia agent) infection in nonimmunosuppressed patients with pneumonia. 19817212505
growth of the pittsburgh pneumonia agent in animal cell cultures.pittsburgh pneumonia agent (legionella micdadei) grew in monkey, chicken, and human cell cultures. pittsburgh pneumonia agent grew predominantly in the cytoplasm, resulting in a nonfocal, mild cytopathic effect.19817287191
detection of cell-associated or soluble antigens of legionella pneumophila serogroups 1 to 6, legionella bozemanii, legionella dumoffii, legionella gormanii, and legionella micdadei by staphylococcal coagglutination tests.current methods used for the detection of whole-cell isolates of legionella or for the detection of legionella soluble antigens are technically impractical for many clinical laboratories. the purpose of this study was to explore practical alternatives. the results showed that whole cell isolates of legionella pneumophila serogroups 1 to 6, legionella bozemanii, legionella dumoffii, legionella gormanii, and legionella micdadei were identified specifically by a simple slide agglutination test or s ...19817287888
successful treatment of legionella micdadei (pittsburgh pneumonia agent) pneumonia with erythromycin.optimal treatment of legionella micdadei pneumonia has not been established, although in vitro studies have shown the pathogen to be sensitive to erythromycin. at our institution, l. micdadei pneumonia was diagnosed in six patients over a one and one-half year period. all patients were immunocompromised and had a typical clinical syndrome; in four of six, diagnosis was made by isolation of the pathogen. all patients received erythromycin (2 to 4 g daily) for 12 to 27 days, and five of six recove ...19817304656
susceptibility of pittsburgh pneumonia agent (legionella micdadei) and other newly recognized members of the genus legionella to nineteen antimicrobial agents.the susceptibilities of 11 strains representing the five recognized species of legionella were determined by agar dilution testing on buffered charcoal-yeast extract agar. all of the legionellae tested were susceptible to rifampin, erythromycin, rosaramycin, chloramphenicol, and the aminoglycosides and were resistant to clindamycin and vancomycin. susceptibilities to penicillins and cephalosporins were variable. legionella micdadei, legionella bozemanii, and legionella gormanii were susceptible ...19817325645
monoclonal antibodies to legionella mip proteins recognize genus- and species-specific epitopes.monoclonal antibodies (mabs) against the virulence-associated mip protein of legionella spp. were raised by immunizing balb/c mice with (i) legionella pneumophila, (ii) legionella micdadei, and (iii) purified recombinant native mip protein cloned from l. pneumophila philadelphia 1. following screening of seeded wells by immunoblot analysis with homologous antigens, eight mip-specific mabs were found. these mabs were chosen to investigate the antigenic diversity of mip proteins in the genus legio ...19957535177
characterization of a legionella micdadei mip mutant.the pathogenesis of legionella micdadei is dependent upon its ability to infect alveolar phagocytes. to better understand the basis of intracellular infection by this organism, we examined the importance of its mip surface protein. in legionella pneumophila, mip promotes infection of both human macrophages and freshwater protozoa. southern hybridization and immunoblot analyses demonstrated that mip sequences were present and expressed within a panel of virulent l. micdadei strains. using allelic ...19957622203
detection of legionella dna in human and guinea pig urine samples by the polymerase chain reaction.a detection system for legionella dna in urine samples based on the polymerase chain reaction (pcr) was developed and tested on infected guinea pigs and patients suffering from pneumonia. results were compared with standard methods for diagnosis of legionnaires' disease. a primer system was selected which amplifies a 108 bp dna fragment of the 5s rrna gene. the sensitivity of the pcr system was one femtogram of extracted legionella dna. three methods were tested for pretreatment of urine samples ...19957729449
phosphatase-negative mutants of legionella pneumophila and their behavior in mammalian cell infection.microbial phosphatases are known or suspected to play a role in the pathogenesis of several intracellular pathogens, including legionella micdadei. legionella pneumophila also possess phosphatase activities, but their possible roles in cellular infection are unknown. we generated mutants of a serogroup 1 isolate of l. pneumophila that lack the major phosphatase. isolation of a pho- mutant after random mutagenesis with transposon mudii4041 allowed us to dissociate the major alkaline phosphatase ( ...19947861953
tissue-directed antibiotics and intracellular parasites: complex interaction of phagocytes, pathogens, and drugs.antibiotics with significant tissue penetration and intracellular accumulation may have an important role in the treatment of intracellular infections. however, clinically relevant evaluation of these antibiotics in vitro remains a challenge. measurement of serum drug concentrations or serum bactericidal levels may not be relevant. measurement of intracellular drug concentrations may be simplistic, given the complex interaction of drug, microbe, and phagocyte. the effect of an antibiotic on an i ...19947893881
genomic heterogenicity amongst phenotypically similar legionella micdadei strains.nine unrelated legionella micdadei strains isolated from clinical and environmental samples have been characterized biochemically, serologically using polyclonal and monoclonal antibodies and by macrorestriction analyses using pulsed-field gel electrophoresis. all strains were positive in the bromocresol purple spot test and grew as blue colonies on dye-containing media. they were positive for catalase, weakly positive for oxidase, and negative for sodium-hippurate hydrolysis, beta-lactamase and ...19957896076
increased synthesis of dnak, groel, and groes homologs by francisella tularensis lvs in response to heat and hydrogen peroxide.the response of the facultative intracellular bacterium francisella tularensis lvs to stress was assayed by pulse-labeling with [35s]methionine followed by two-dimensional gel electrophoresis and autoradiography. a temperature increase from 37 to 42 degrees c or exposure to 5 mm hydrogen peroxide induced increased syntheses of at least 15 proteins. among these proteins were a 75-, a 60-, and a 10-kda protein. by n-terminal sequence analysis, these three proteins were found to be extensively homo ...19947903283
legionella micdadei prosthetic valve endocarditis.legionella usually causes pneumonia, but occasionally is in the differential diagnosis of "culture negative endocarditis" which sometimes involves prosthetic heart valves. legionella prosthetic valve endocarditis is nearly always due to legionella pneumophila and its clinical presentation is indistinguishable from other causes of prosthetic valve endocarditis. diagnosis of legionella prosthetic valve endocarditis is by recovery of the organism from the blood, demonstration or isolation of the or ...19947927821
composition of 2,3-dihydroxy fatty acid-containing lipopolysaccharides from legionella israelensis, legionella maceachernii and legionella micdadei.lipopolysaccharides (lps) from legionella israelensis, l. maceachernii and l. micdadei were analysed for chemical composition. the main sugar of the lipid a fractions was in each case 2,3-diamino-2,3-dideoxy-d-glucose. lipid a of l. israelensis also contained a substantial amount of d-glucosamine. in each lipid a fraction a complex fatty acid pattern was detected. this comprised at least 19 different 3-hydroxy fatty acids (amide-linked), three 2,3-dihydroxy fatty acids (amide-linked), non-hydrox ...19948081491
azithromycin inhibition of intracellular legionella micdadei.legionella micdadei is an intracellular parasite that is ingested, but not killed, by leukocytes. within monocytes, the organism has been shown to grow 1.0 to 2.0 log10 units over 48 h (d. l. weinbaum, r. r. benner, j. n. dowling, a. alpern, a. w. pasculle, and g. r. donowitz, infect. immun. 46:68-73, 1984). intracellular l. micdadei would appear to be a useful model in which to study the effect of antibiotics which accumulate intracellularly. azithromycin, a newly introduced azalide, is highly ...19938285604
demonstration of lectin-like activity for the common antigen of neisseria gonorrhoeae by quantitative immunoelectrophoretic techniques.to overcome problems associated with western blotting of denatured proteins, we have used quantitative immunoelectrophoretic techniques to perform functional analysis of the neisseria gonorrhoeae common antigen. using these techniques, we show (a) that neisseria gonorrhoeae expresses an antigen that is cross-reactive with the common antigen of pseudomonas aeruginosa and legionella micdadei and with the groel-like protein of chlamydia, and (b) that this n. gonorrhoeae common antigen has lectin-li ...19938319879
properties of the genus tatlockia. differentiation of tatlockia (legionella) maceachernii and micdadei from each other and from other legionellae.the biochemical reactions, carbohydrate content, and 16s-rrna sequences of tatlockia (legionella) maceachernii and tatlockia micdadei strains were studied. except for catalase activity, tatlockia strains were relatively inert in the biochemical tests commonly used in clinical laboratories. phenotypically, the two tatlockia species could be distinguished from other legionellae by the presence of yersiniose a, by their inability to hydrolyze hippurate or starch, by the absence of colony or media f ...19938330260
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 ...19958549715
the legionella micdadei flagellin: expression in escherichia coli k 12 and dna sequence of the gene.to study the structure and function of the legionella flagellum, we screened a genomic l. micdadei library in escherichia coli for expression of the flagellin (fla) subunit. one recombinant clone, jm105 (phi5588), producing a truncated fla protein of 40.5 kda was identified. the plasmid phi5588 carried a l. micdadei dna insert of 5 kb, containing ca 95% of the fla gene. the complete dna sequence of the l. micdadei fla gene was obtained by combining sequence data from phi5588 with results using a ...19958562027
[a case of legionella micdadei pneumonia].a 60-year-old male with type c chronic hepatitis was admitted to kibikogen rehabilitation center with high fever, cough and general fatigue. chest x-ray film on admission showed consolidation in the left middle and lower lung lung field. initial treatment with intravenous ceftazidime, imipenem/cilastatin and clindamycin were ineffective due to continuous high fever and cough and spread of the pneumonia shadow. administration of minocycline was started for suspected non-bacterial pneumonia whereu ...19968621971
lung abscess caused by legionella micdadei.we describe a case of lung abscess caused by sporadic infection with legionella micdadei in a patient with aids. l micdadei infection can be very difficult to diagnose because the organism stains only weakly gram negative, requires special culture media, and is not detectable with some direct fluorescent antibody tests that are directed only at legionella pneumophila. since it can stain acid fast, it may be confused with mycobacteria. the abscess was successfully treated using antibiotics and pe ...19978996029
serological cross-reactions between coxiella burnetii and legionella micdadei.coxiella burnetii and legionella micdadei are both gram-negative bacteria potentially responsible for identical clinical syndromes resembling upper respiratory infections. these infections, quite common in immunocompromised patients, are usually diagnosed by serology with a microimmunofluorescence assay. we found that 34.5% of q fever patients had a significant titer of antibodies against l. micdadei. cross-reactions involved immunoglobulin g antibodies and were demonstrated by a cross-adsorptio ...19979067657
lung abcess complicating legionella micdadei pneumonia in an adult liver transplant recipient: case report and review.legionella micdadei (pittsburgh pneumonia agent) is the second most common cause of legionella pneumonia, and occurs predominantly in immunocompromised hosts. l micdadei is the cause of nosocomial pneumonia in renal transplant recipients, but has not been described in other adult solid organ transplant recipients. this report describes the first case of l micdadei pneumonia in an adult liver transplant recipient on immunosuppressive therapy. importantly, this case highlights the difficulties in ...19989448158
variation in flagellin genes and proteins of burkholderia cepacia.the majority of isolates of burkholderia cepacia, an important opportunistic pathogen associated with cystic fibrosis, can be classified into two types on the basis of flagellin protein size. electron microscopic analysis indicates that the flagella of strains with the larger flagellin type (type i) are wider in diameter. flagellin genes representative of both types were cloned and sequenced to design oligonucleotide primers for pcr amplification of the central variable domain of b. cepacia flag ...19989495748
a review of the in-vitro activity of quinupristin/dalfopristin against intracellular pathogens and mycoplasmas.quinupristin/dalfopristin displays in-vitro bacteriostatic activity against all legionella spp. (mics = 0.06-2 mg/l), with legionella pneumophila usually being at least two-fold more sensitive to quinupristin/dalfopristin than legionella bozemanii, legionella dumoffii, legionella gormanii and legionella micdadei (mic = 0.06-2 vs 1-2 mg/l, respectively). against legionella spp., quinupristin/dalfopristin was at least as active as erythromycin. quinupristin/dalfopristin was active in vitro against ...19979511064
immunoreactivity of five monoclonal antibodies against the 37-kilodalton common cell wall protein (psaa) of streptococcus pneumoniae.five monoclonal antibodies (mabs) were produced against the streptococcus pneumoniae pneumococcal surface adhesin a (psaa) 37-kda common cell wall protein. these antibodies were used in a dot immunoblot and western blot study of clinical isolates of s. pneumoniae to detect the presence of the protein. by both assays, the mabs reacted with clinical isolates representing the 23 type-specific serotypes present in the licensed pneumococcal polysaccharide vaccine. western blot analysis confirmed the ...19989521144
sequence analysis of the mip gene of the soilborne pathogen legionella longbeachae.to understand the basis of pathogenesis by legionella longbeachae serogroup 1, the importance of the mip protein in this species was examined. amino-terminal analysis of the purified, cloned l. longbeachae serogroup 1 atcc 33462 mip protein confirmed that the cloned gene protein was expressed and processed in an escherichia coli background. dna sequence analysis of plasmid pimvs27, containing the entire l. longbeachae serogroup 1 mip gene, revealed a high degree of homology to the mip gene of le ...19989529072
identification and temperature regulation of legionella pneumophila genes involved in type iv pilus biogenesis and type ii protein secretion.previously, we had isolated by transposon mutagenesis a legionella pneumophila mutant that appeared defective for intracellular iron acquisition. while sequencing in the proximity of the mini-tn10 insertion, we found a locus that had a predicted protein product with strong similarity to pilb from pseudomonas aeruginosa. pilb is a component of the type ii secretory pathway, which is required for the assembly of type iv pili. consequently, the locus was cloned and sequenced. within this 4-kb regio ...19989529113
systemic lupus erythematosus: a risk factor for pneumonia caused by legionella micdadei? 19979531245
activity of azithromycin, clarithromycin, roxithromycin, dirithromycin, quinupristin/dalfopristin and erythromycin against legionella species by intracellular susceptibility testing in hl-60 cells.we evaluated a human monocyte cell line (hl-60) as a model for testing the intracellular activity of anti-legionella antibiotics; 1.5 x 10(6) hl-60 cells/well were differentiated into adherent cells and infected with 1.5 x 10(7) cfu of legionella pneumophila. the most active agents against l. pneumophila as judged by broth dilution mics were (in order of activity) azithromycin, clarithromycin, roxithromycin, quinupristin/dalfopristin, erythromycin and dirithromycin. the most active inhibitors of ...19989533475
nosocomial pneumonia caused by three genetically different strains of legionella pneumophila and detection of these strains in the hospital water supply.a 44-year-old woman developed legionella pneumophila pneumonia after cerebral surgery. initially, one colony from a clinical specimen and two colonies from water samples, all belonging to serogroup 12, did not match when their dna restriction patterns were compared. when additional colonies from the water specimens were analyzed, a serogroup 12 strain complementary to that found in the clinical specimen was identified. other colonies from the clinical specimen were identified as serogroup 12 str ...19989542962
signal transduction during legionella pneumophila entry into human monocytes.legionella pneumophila causes legionnaires' disease by replication in alveolar macrophages and monocytes. the bacteria are internalized most efficiently by opsonin-dependent, cr3-mediated phagocytosis. this investigation focused on determining the role of actin polymerization and phosphorylation signals in this uptake mechanism. uptake inhibition assays and confocal microscopic analysis indicated that entry of l. pneumophila activated tyrosine kinase (tk) and protein kinase c (pkc) and induced a ...19989596766
sequence-based classification scheme for the genus legionella targeting the mip gene.the identification and speciation of strains of legionella is often difficult, and even the more successful chromatographic classification techniques have struggled to discriminate newly described species. a sequence-based genotypic classification scheme is reported, targeting approximately 700 nucleotide bases of the mip gene and utilizing gene amplification and direct amplicon sequencing. with the exception of legionella geestiana, for which an amplicon was not produced, the scheme clearly and ...19989620377
an outbreak of pontiac fever among children following use of a whirlpool.we investigated an outbreak of fever, most likely due to a contaminated whirlpool, among nine adults and six children residing in a summerhouse. the outbreak was characterized by a high attack rate, short incubation periods, influenza-like symptoms, and rapid recoveries, all features typical of pontiac fever. however, the children had less-characteristic symptoms than the adults, and they did not have any sequelae. findings on the children's chest radiographs were unremarkable, and none of the c ...19989636866
specific detection of legionella pneumophila: construction of a new 16s rrna-targeted oligonucleotide probe.based on comparative sequence analysis, we have designed an oligonucleotide probe complementary to a region of 16s rrna of legionella pneumophila which allows the differentiation of l. pneumophila from other legionella species without cultivation. the specificity of the new probe, legpne1, was tested by in situ hybridization to a total of four serogroups of six strains of l. pneumophila, five different legionella spp. and three nonlegionella species as reference strains. furthermore, l. pneumoph ...19989647849
diagnosis of q fever. 19989650920
epidemiological and environmental investigations of legionella pneumophila infection in cattle and case report of fatal pneumonia in a calf.a fatal pneumonia due to legionella pneumophila was diagnosed in a young calf reared in a dairy herd located in northern italy. clinical symptoms consisted of watery diarrhea, hyperthermia, anorexia, and severe dyspnea. the pathological and histological findings were very similar to those observed in human legionellosis. legionella pneumophila serogroup 1 (sg1) and sg10 were isolated from the calfs lung, and l. pneumophila sg1 was isolated from the calfs liver. l. pneumophila sg1 was also demons ...19989650941
comparison of the binax legionella urinary antigen enzyme immunoassay (eia) with the biotest legionella urin antigen eia for detection of legionella antigen in both concentrated and nonconcentrated urine samples.we evaluated a newly commercial enzyme immunoassay (eia) (biotest legionella urin antigen eia; biotest ag, dreieich, germany) for detection of antigens of all legionella pneumophila serogroups with a relatively wide spectrum of cross-reactivity as well as antigens of other legionella spp. by comparing its sensitivity and specificity with those of an eia for detection of l. pneumophila serogroup 1 antigen (legionella urinary antigen eia; binax, portland, maine). both tests were performed with bot ...19989705420
low endotoxic potential of legionella pneumophila lipopolysaccharide due to failure of interaction with the monocyte lipopolysaccharide receptor cd14.legionella pneumophila, a gram-negative bacterium causing legionnaires' disease and pontiac fever, was shown to be highly reactive in in vitro gelation of limulus lysate but not able to induce fever and the local shwartzman reaction in rabbits and mice. we analyzed the capacity of purified l. pneumophila lipopolysaccharide (lps-lp) to induce activation of the human monocytic cell line mono mac 6, as revealed by secretion of proinflammatory cytokines and desensitization to subsequent lps stimulat ...19989712761
invasion of protozoa by legionella pneumophila and its role in bacterial ecology and pathogenesis. 19989726849
signal transduction in the protozoan host hartmannella vermiformis upon attachment and invasion by legionella micdadei.the intracellular pathogens legionella micdadei and legionella pneumophila are the two most common legionella species that cause legionnaires' disease. intracellular replication within pulmonary cells is the hallmark of legionnaires' disease. in the environment, legionellae are parasites of protozoans, and intracellular bacterial replication within protozoans plays a major role in the transmission of legionnaires' disease. in this study, we characterized the initial host signal transduction mech ...19989726850
identification of a 71-kilodalton surface-associated hsp70 homologue in coxiella burnetii.a coxiella burnetii hsp70 homologue was identified by using an acid activation in vitro system in which protein synthesis has been followed by [35s]methionine labeling, autoradiography, and immunoblotting. the protein was one of those predominantly labeled, and the immunoblots revealed that it was recognized by anti-dnak antibodies. the corresponding gene was isolated, and its nucleotide sequence was determined and analyzed. a single open reading frame (orf) with a size of 1,968 bp was identifie ...19989826369
systemic infection of an immunocompromised patient with methylobacterium zatmanii.we describe the identification of methylobacterium zatmanii as the causative agent of bacteremia and fever in an immunocompromised patient. the patient, a 60-year-old man, had a 5-month history of acute myeloid leukemia and had been on chemotherapy throughout this period. seven days after the onset of neutropenia, the patient developed fever. the combination of ciprofloxacin, co-trimoxazole, imipenem, amikacin, and vancomycin led to a complete defervescence. on subculture from six positive blood ...19999854105
[severe legionella micdadei pneumonia effectively treated with hemofiltration therapy].a 42-year-old man was admitted because of fever, productive cough, and progressive dyspnea. chest x-ray films and computed tomographic scans disclosed dense consolidation in the left and right lung fields. no pathogenic agent was found despite extensive bacteriological examinations. based on serological findings, the patient was given a diagnosis of acute pneumonia caused by legionella micdadei. it has been reported that legionnaire's disease is easily complicated by fatal systemic illnesses suc ...19989893432
[epidemiological studies on legionella infection in taiyuan area of shanxi province].to study the prevalence and epidemic features of legionella infection in taiyuan area of shanxi province.199810322756
bilateral pleuritis caused by legionella micdadei.a 58-year-old woman was hospitalized because of progressive respiratory distress. she had a history of myasthenia gravis and invasive thymoma. after thymectomy, she had been administered oral prednisolone and intrathoracic anti-cancer drugs postoperatively. her chest radiograph revealed bilateral pleural effusions. legionella micdadei (l. micdadei) was isolated from the pleural effusions, and she was diagnosed as pleuritis caused by l. micdadei. she died despite intensive therapy with mechanical ...199910361912
usefulness of fatty acid composition for differentiation of legionella species.numerical analysis of fatty acid methyl ester (fame) profiles of 199 isolates and 76 reference strains, belonging to all validly described species of the genus legionella that can be cultured in laboratory media, was used to differentiate between the species of this genus. with the exception of the strains that autofluoresced red, it was possible to differentiate all the other legionella species. the strains of the species l. bozemanii, l. dumoffii, l. feeleii, l. gormanii, l. maceachernii, l. m ...199910364593
identification and characterization of a flagellin gene from the endosymbiont of the hydrothermal vent tubeworm riftia pachyptila.the bacterial endosymbionts of the hydrothermal vent tubeworm riftia pachyptila play a key role in providing their host with fixed carbon. results of prior research suggest that the symbionts are selected from an environmental bacterial population, although a free-living form has been neither cultured from nor identified in the hydrothermal vent environment. to begin to assess the free-living potential of the symbiont, we cloned and characterized a flagellin gene from a symbiont fosmid library. ...199910388713
comparative analysis of legionella pneumophila and legionella micdadei virulence traits.while the majority of legionnaire's disease has been attributed to legionella pneumophila, legionella micdadei can cause a similar infection in immunocompromised people. consistent with its epidemiological profile, the growth of l. micdadei in cultured macrophages is less robust than that of l. pneumophila. to identify those features of the legionella spp. which are correlated to efficient growth in macrophages, two approaches were taken. first, a phenotypic analysis compared four clinical isola ...199910417184
australian isolates of legionella longbeachae are not a clonal population.legionella longbeachae is almost as frequent a cause of legionellosis in australia as legionella pneumophila, but epidemiological investigation of possible environmental sources and clinical cases has been limited by the lack of a discriminatory subtyping method. the purpose of this study was to examine the genetic variability among australian isolates of l. longbeachae serogroup 1. pulsed-field gel electrophoresis (pfge) of sfii fragments revealed three distinct pulsotypes among 57 clinical and ...199910488187
relapsing life threatening community acquired pneumonia due to rare legionella species responsive to ceftriaxone and aztreonam.a 24 year old saudi housewife was admitted thrice with life threatening community acquired pneumonia. even though she responded to an initial cocktail of cefriaxone, erythromcin, rifampicin and flucloxacillin during the second admission, she relapsed within four days of discharge when she was on erythromycin only. during the third admission she was put on ceftriaxone and aztreonam and recovered fully without any relapse. serology results received later showed legionella igm titres of more than 1 ...199810497650
q fever.q fever is a zoonosis with a worldwide distribution with the exception of new zealand. the disease is caused by coxiella burnetii, a strictly intracellular, gram-negative bacterium. many species of mammals, birds, and ticks are reservoirs of c. burnetii in nature. c. burnetii infection is most often latent in animals, with persistent shedding of bacteria into the environment. however, in females intermittent high-level shedding occurs at the time of parturition, with millions of bacteria being r ...199910515901
outer membrane lipoprotein e (p4) of haemophilus influenzae is a novel phosphomonoesterase.haemophilus influenzae exists as a commensal of the upper respiratory tract of humans but also causes infections of contiguous structures. we describe the identification, localization, purification, and characterization of a novel, surface-localized phosphomonoesterase from a nontypeable h. influenzae strain, r2866. sequences obtained from two cnbr-derived fragments of this protein matched lipoprotein e (p4) within the h. influenzae sequence database. escherichia coli dh5alpha transformed with p ...199910542183
heterogeneity in intracellular replication and cytopathogenicity of legionella pneumophila and legionella micdadei in mammalian and protozoan cells.in contrast to legionella pneumophila, little is known about the pathogenesis of other legionellae species that are capable of causing legionnaires' disease. in this report, we contrast l. pneumophila and l. micdadei for their cytopathogenicity and intracellular replication within mammalian and protozoan cells. we show by transmission electron microscopy that l. micdadei replicates within an endoplasmic reticulum (rer)-free phagosome within human macrophages, alveolar epithelial cells, and withi ...199910545255
discovery of a nonclassical siderophore, legiobactin, produced by strains of legionella pneumophila.the mechanisms by which legionella pneumophila, a facultative intracellular parasite and the agent of legionnaires' disease, acquires iron are largely unexplained. several earlier studies indicated that l. pneumophila does not elaborate siderophores. however, we now present evidence that supernatants from l. pneumophila cultures can contain a nonproteinaceous, high-affinity iron chelator. more specifically, when aerobically grown in a low-iron, chemically defined medium (cdm), l. pneumophila sec ...200010633110
novel phospholipase a activity secreted by legionella species.bacterial phospholipases are regarded as a major virulence factor in infection. in bacteria associated with pneumonia, destruction of lung surfactant and host cell membranes by bacterial phospholipases secreted during infection is thought to contribute to the disease. phospholipase c (plc) activity has been described in several legionella species (w. b. baine, j. gen. microbiol. 134:489-498, 1988; w. b. baine, j. gen. microbiol. 131:1383-1391, 1985). by using detection methods such as thin-layer ...200010671453
the legionella pneumophila iraab locus is required for iron assimilation, intracellular infection, and virulence.legionella pneumophila, a facultative intracellular parasite of human alveolar macrophages and protozoa, causes legionnaires' disease. using mini-tn10 mutagenesis, we previously isolated a l. pneumophila mutant that was hypersensitive to iron chelators. this mutant, nu216, and its allelic equivalent, nu216r, were also defective for intracellular infection, particularly in iron-deficient host cells. to determine whether nu216r was attenuated for virulence, we assessed its ability to cause disease ...200010678909
[a serological investigation of legionella infection in six-species of poultries and domestic animals in luzhou city, sichuan province].to understand the prevalence rates of legionella infection in poutries and domestic animals in luzhou city.199910682546
secreted enzymatic activities of wild-type and pild-deficient legionella pneumophila.legionella pneumophila, the agent of legionnaires' disease, is an intracellular pathogen of protozoa and macrophages. previously, we had determined that the legionella pild gene is involved in type iv pilus biogenesis, type ii protein secretion, intracellular infection, and virulence. since the loss of pili and a protease do not account for the infection defect exhibited by a pild-deficient strain, we sought to define other secreted proteins absent in the mutant. based upon the release of p-nitr ...200010722574
identification and subcellular localization of the legionella pneumophila icmx protein: a factor essential for establishment of a replicative organelle in eukaryotic host cells.the gram-negative respiratory pathogen legionella pneumophila infects and grows within mammalian macrophages and protozoan host cells. upon uptake into macrophages, l. pneumophila establishes a replicative organelle that avoids fusion with endocytic vesicles. there are 24 dot/icm genes on the l. pneumophila chromosome required for biogenesis of this vacuole. many of the dot/icm proteins are predicted to be components of a membrane-bound secretion apparatus similar to type iv conjugal transfer sy ...200010858211
recombinant chimeric borrelia proteins for diagnosis of lyme disease.current serologic lyme disease tests use whole borrelia cells as the source of antigen. these assays are difficult to standardize and to optimize for sensitivity and specificity. to help solve these problems, we constructed a library of recombinant chimeric proteins composed of portions of key antigens of borrelia burgdorferi. these proteins were then used to develop an enzyme-linked immunosorbent assay. we compared our assay with the most sensitive of three whole-cell borrelia assays. we found ...200010878038
sequencing of the rpob gene in legionella pneumophila and characterization of mutations associated with rifampin resistance in the legionellaceae.rifampin in combination with erythromycin is a recommended treatment for severe cases of legionellosis. mutations in the rpob gene are known to cause rifampin resistance in escherichia coli and mycobacterium tuberculosis, and the purpose of the present study was to investigate a possible similar resistance mechanism within the members of the family legionellaceae. since the rna polymerase genes of this genus have never been characterized, the dna sequence of the legionella pneumophila rpob gene ...200010991843
an outbreak of legionella micdadei pneumonia in transplant patients: evaluation, molecular epidemiology, and control.to describe a nosocomial outbreak of legionella micdadei pneumonia in transplant patients and to characterize the source of the outbreak and the control measures utilized.200011014721
nosocomial legionella micdadei infection in transplant patients: fortune favors the prepared mind. 200011014731
temporal pore formation-mediated egress from macrophages and alveolar epithelial cells by legionella pneumophila.legionella pneumophila does not induce apoptosis in the protozoan host, but induces pore formation-mediated cytolysis after termination of intracellular replication (l.-y. gao and y. abu kwaik, environ. microbiol. 2:79-90, 2000). in contrast to this single mode of killing of protozoa, we have recently proposed a biphasic model by which l. pneumophila kills macrophages, in which the first phase is manifested through the induction of apoptosis during early stages of the infection, followed by an i ...200011035756
localization of legionella bacteria within ribosome-studded phagosomes is not restricted to legionella pneumophila.in this report, we investigate the intracellular fate of selected members of the genus legionella within the monocytic cell line mono mac 6 cells. by means of electron microscopy and immunocytochemistry, we could show that legionella pneumophila as well as legionella longbeachae are able to induce ribosome-studded phagosomes which associate with the rough endoplasmic reticulum (rer), whereas legionella micdadei remains to be located within smooth phagosomes but also shows signs of rer associatio ...200011040443
secretion of an acid phosphatase (sapm) by mycobacterium tuberculosis that is similar to eukaryotic acid phosphatases.mycobacterium tuberculosis secretes a large number of polypeptides with broad biological and immunological functions. we describe here the characterization of a 28-kda acid phosphatase of m. tuberculosis (sapm) localized to the culture filtrate. the mature protein demonstrated biochemical characteristics similar to those of the bacterial nonspecific acid phosphatases. however, sapm yielded significant sequence homology to fungal acid phosphatases and not those of bacteria. thus, sapm may represe ...200011073936
essential role for the legionella pneumophila rep helicase homologue in intracellular infection of mammalian cells.we have previously isolated 32 mutants of legionella pneumophila that are defective in the infection of mammalian cells but not protozoa. the mutated loci have been designated macrophage-specific infectivity (mil) loci. in this study we characterized the mil mutant gk11. this mutant was incapable of growth within u937 macrophage-like cells and wi-26 alveolar epithelial cells. this defect in intracellular replication correlated with a defect in cytopathogenicity to these cells. sequence analysis ...200011083821
legionella pneumophila major acid phosphatase and its role in intracellular infection.legionella pneumophila is an intracellular pathogen of protozoa and alveolar macrophages. this bacterium contains a gene (pild) that is involved in both type iv pilus biogenesis and type ii protein secretion. we previously demonstrated that the pild prepilin peptidase is crucial for intracellular infection by l. pneumophila and that the secreted pild-dependent proteins include a metalloprotease, an acid phosphatase, an esterase/lipase, a phospholipase a, and a p-nitrophenyl phosphorylcholine hyd ...200111119504
rapid identification of clinically relevant legionella spp. by analysis of transfer dna intergenic spacer length polymorphism.analysis of pcr-amplified transfer dna (tdna) intergenic spacers was evaluated as a rapid method for identification to the species level of 18 species of legionella known as human pathogens. type strains (n = 19), reference strains (n = 16), environmental strains (n = 31), and clinical strains (n = 32) were tested. pcr products using outwardly directed tdna consensus primers were separated on polyacrylamide gels and analyzed with automated laser fluorescence. test results were obtained in 8 h st ...200111136765
endocarditis due to rare and fastidious bacteria.the etiologic diagnosis of infective endocarditis is easily made in the presence of continuous bacteremia with gram-positive cocci. however, the blood culture may contain a bacterium rarely associated with endocarditis, such as lactobacillus spp., klebsiella spp., or nontoxigenic corynebacterium, salmonella, gemella, campylobacter, aeromonas, yersinia, nocardia, pasteurella, listeria, or erysipelothrix spp., that requires further investigation to establish the relationship with endocarditis, or ...200111148009
chemokine-dependent neutrophil recruitment in a murine model of legionella pneumonia: potential role of neutrophils as immunoregulatory cells.the roles of cxc chemokine-mediated host responses were examined with an a/j mouse model of legionella pneumophila pneumonia. after intratracheal inoculation of 10(6) cfu of l. pneumophila, the bacterial numbers in the lungs increased 10-fold by day 2; this increase was accompanied by the massive accumulation of neutrophils. reverse transcription-pcr data demonstrated the up-regulation of cxc chemokines, such as keratinocyte-derived chemokine, macrophage inflammatory protein 2 (mip-2), and lipop ...200111254553
htra homologue of legionella pneumophila: an indispensable element for intracellular infection of mammalian but not protozoan cells.legionella pneumophila replicates within alveolar macrophages, and possibly, alveolar epithelial cells and also within protozoa in the aquatic environment. here we characterize an l. pneumophila mutant defective in the htra/degp stress-induced protease/chaperone homologue and show that htra is indispensable for intracellular replication within mammalian macrophages and alveolar epithelial cells and for intrapulmonary replication in a/j mice. importantly, amino acid substitutions of two conserved ...200111254621
a whirlpool associated outbreak of pontiac fever at a hotel in northern sweden.in april 1999, an outbreak of pontiac fever occurred at a hotel in northern sweden. a retrospective cohort study to find the source and define the extent of the outbreak was carried out among 530 swedish and norwegian guests. twenty-nine epidemiological cases (8% of 378 responders) aged 21-57 years were identified. antibodies against legionella micdadei were detected in 17 of 27 tested cases and 3 other symptomatic persons. visiting the whirlpool area was identified as the sole risk factor (rr 8 ...200111349975
identification of legionella pneumophila rcp, a pagp-like gene that confers resistance to cationic antimicrobial peptides and promotes intracellular infection.in the course of characterizing a locus involved in heme utilization, we identified a legionella pneumophila gene predicted to encode a protein with homology to the product of the salmonella enterica serovar typhimurium pagp gene. in salmonella, pagp increases resistance to the bactericidal effects of cationic antimicrobial peptides (camps). mutants with insertions in the l. pneumophila pagp-like gene were generated and showed decreased resistance to different structural classes of camps compare ...200111401964
legionella micdadei lung abscess in a patient with hiv-associated nephropathy.a patient with end-stage renal disease due to human immunodeficiency-associated nephropathy developed fever, cough and chest pain over a week's duration. he was diagnosed with lung abscess and started on antibiotic coverage. he underwent bronchoscopy because of progression of his illness and persistent fever and bronchoalveolar lavage culture isolated legionella micdadei. in spite of appropriate antibiotic therapy, the patient remained febrile for 10 days, necessitating chest tube drainage. afte ...200111446394
comparison of virulence of legionella longbeachae strains in guinea pigs and u937 macrophage-like cells.a guinea pig model of experimental legionellosis was established for assessment of virulence of isolates of legionella longbeachae. the results showed that there were distinct virulence groupings of l. longbeachae serogroup 1 strains based on the severity of disease produced in this model. statistical analysis of the animal model data suggests that australian isolates of l. longbeachae may be inherently more virulent than non-australian strains. infection studies performed with u937 cells were c ...200111500403
detection of legionellae in hospital water samples by quantitative real-time lightcycler pcr.contamination of hospital water systems with legionellae is a well-known cause of nosocomial legionellosis. we describe a new real-time lightcycler pcr assay for quantitative determination of legionellae in potable water samples. primers that amplify both a 386-bp fragment of the 16s rrna gene from legionella spp. and a specifically cloned fragment of the phage lambda, added to each sample as an internal inhibitor control, were used. the amplified products were detected by use of a dual-color hy ...200111525995
v gamma 9v delta 2 t cells in human legionellosis.in humans, expansion of circulating vgamma9vdelta2 t cells seems to be a pathophysiological denominator shared by protozoan and intracellular bacterial diseases. the assumption was tested here on legionellosis, a condition conforming to the category but not yet described with respect to gammadelta t cells. levels of vgamma9vdelta2 t cells in peripheral blood were measured at various intervals in 14 subjects undergoing a pontiac fever-like disease, shown by serological investigation to be caused ...200111527809
in vitro activity of abt-773 against legionella pneumophila, its pharmacokinetics in guinea pigs, and its use to treat guinea pigs with l. pneumophila pneumonia.the activity of abt-773 was studied against extracellular and intracellular legionella pneumophila and for the treatment of guinea pigs with l. pneumophila pneumonia. the abt-773 mic at which 50% of isolates are inhibited (mic(50)) for 20 different legionella sp. strains was 0.016 microg/ml, whereas the mic(50)s of clarithromycin and erythromycin were 0.032 and 0.125 microg/ml, respectively. abt-773 (1 microg/ml) was bactericidal for two l. pneumophila strains grown in guinea pig alveolar macrop ...200111557455
infection of acanthamoeba polyphaga with simkania negevensis and s. negevensis survival within amoebal cysts.simkania negevensis, a novel microorganism belonging to the family simkaniaceae in the order chlamydiales, has an intracellular developmental cycle during which two morphological entities, elementary bodies (eb) and reticulate bodies (rb), are seen by electron microscopy. rates of seropositivity to the organism are high in certain population groups, and s. negevensis has been associated with respiratory illness in humans. this study reports for the first time the ability of s. negevensis to surv ...200111571186
pontiac fever due to legionella micdadei from a whirlpool spa: possible role of bacterial endotoxin.during january 1998, a cluster of illnesses occurred among hotel guests in wisconsin. ill persons had been exposed to the hotel's whirlpool spa and swimming pool. symptoms included headache, fever, chills, myalgia, shortness of breath, and fatigue. a diagnosis of pontiac fever was made, based on serologic evidence of acute infection with legionella micdadei. high concentrations of heterotrophic bacteria were recovered from the spa, despite apparently high disinfectant levels. l. micdadei was iso ...200111679917
recurrent soft tissue abscesses caused by legionella cincinnatiensis.recurrent soft tissue abscesses of the jaw, wrist, and arm developed in a 73-year-old housewife with nephrotic syndrome and immunoglobulin a(kappa) gammopathy of unknown etiology. conventional cultures remained negative, despite visible gram-negative rods on microscopy. broad-spectrum pcr revealed legionella cincinnatiensis, which was confirmed by isolation of the organism on special legionella medium. infections due to legionella species outside the lungs are rare. l. cincinnatiensis has been i ...200111724886
comparison of serologic tests with urinary antigen detection for diagnosis of legionnaires' disease in patients with community-acquired pneumonia.objective: to compare serologic methods and detection of urinary antigen in the diagnosis of community-acquired pneumonia. methods: paired sera from 84 patients with community-acquired pneumonia were tested for legionella pneumophila serogroup (lp sg) 1-7 and legionella micdadei by use of the indirect immunofluorescence antibody test (iif), enzyme-linked immunosorbent assay (elisa) for lp sg 1-7 and complement-fixation (cf) test for lp sg 1. all patients were evaluated by elisa urinary antigen d ...199911856250
[a serological investigation of legionella infection in eight-species of poultry and domestic animals in sichuan province].to understand the prevalence rates of legionella infection in poultries and domestic animals in sichuan province.200011860816
population genetic structure of legionella pneumophila inferred from rna polymerase gene (rpob) and dota gene (dota) sequences.the population structure of legionella pneumophila was studied by using partial rna polymerase gene (rpob) and dota gene (dota) sequences. trees inferred from rpob sequences showed that two subspecies of l. pneumophila, legionella pneumophila subsp. pneumophila and legionella pneumophila subsp. fraseri, were clearly separated genetically. in both rpob and dota trees, 79 korean isolates used in this study constituted six clonal populations, four of which (designated subgroups p-i to p-iv) were id ...200211914343
direct detection and differentiation of legionella spp. and legionella pneumophila in clinical specimens by dual-color real-time pcr and melting curve analysis.a dual-color lightcycler pcr assay targeting the 16s rdna gene of legionella spp. was established. by using two pairs of hybridization probes, legionella spp. and legionella pneumophila could be detected and differentiated simultaneously. with 26 culture-positive and 42 culture-negative respiratory specimens from patients with atypical pneumonia, 100% sensitivity and specificity was observed for l. pneumophila.200212354888
tularemia.francisella tularensis is the etiological agent of tularemia, a serious and occasionally fatal disease of humans and animals. in humans, ulceroglandular tularemia is the most common form of the disease and is usually a consequence of a bite from an arthropod vector which has previously fed on an infected animal. the pneumonic form of the disease occurs rarely but is the likely form of the disease should this bacterium be used as a bioterrorism agent. the diagnosis of disease is not straightforwa ...200212364373
extrapulmonary legionella micdadei infection in a previously healthy child.a previously healthy 9-year-old girl presented with a 1-week history of left neck mass and low grade fever. surgical drainage specimens from the mass were bacterial culture-negative. legionella micdadei infection was diagnosed by a two step pcr-nucleic acid sequencing method and supported by organism-specific serology. a backyard hot tub was suspected as the source of infection.200212508793
comparison of lightcycler pcr, rapid antigen immunoassay, and culture for detection of group a streptococci from throat swabs.we compared the performance characteristics of a real-time pcr method, the lightcycler strep-a assay (roche applied science, indianapolis, ind.), to those of a rapid antigen immunoassay, the directigen 1-2-3 group a strep test kit (bd diagnostic systems, sparks, md.), and a standard culture method for detection of group a streptococci (gas) from 384 throat swabs. the lightcycler pcr produced more positive results (n = 58) than either culture (n = 55) or the directigen immunoassay (n = 31). the r ...200312517855
detection of legionella dna by pcr of whole-blood samples in a mouse model.a detection system for legionella dna in blood samples based on the pcr was developed and evaluated in a/j mice with experimentally induced legionella pneumonia. primers were designed to amplify a 106 bp dna fragment of the 16s rrna gene specific to legionella species. the pcr system could detect clinically relevant legionella species including legionella pneumophila, legionella micdadei, legionella bozemanae, legionella dumoffii, legionella longbeachae, legionella gormanii and legionella jordan ...200312676871
characterization of a tandem repeat polymorphism in legionella pneumophila and its use for genotyping.we have analyzed the variability of minisatellite sequences (also called variable-number tandem repeats [vntrs]) in the genome of legionella pneumophila. based upon the genome sequence of the philadelphia-1 strain (serogroup 1), 25 minisatellites were selected and their polymorphisms were analyzed by pcr with the dna of serogroup 1 to 14 reference strains. for 22 markers, a pcr product of the expected size was found with the dna of the philadelphia-1 strain. most of these markers did not amplify ...200312734211
neonatal sudden death due to legionella pneumonia associated with water birth in a domestic spa bath.we report the first case of neonatal legionnaires' disease associated with water birth in a spa bath at home. legionella pneumophila serogroup 6 was detected from postmortem lung tissue.200312734286
[rapid and simple detection of legionella species by lamp, a mew dna amplification method].legionella is a common cause of community-acquired respiratory tract infections and occasionally causes nosocomial pneumonia. rapid and accurate detection of legionellae is important for diagnosis and treatment of patients. in order to detect legionellae, a new dna amplification method was designed and evaluated. loop-mediated isothermal amplification (lamp) method amplifies dna with high specificity, sensitivity, and rapidity under isothermal conditions at 65 degrees c. this method employs a dn ...200314984304
legionella pneumophila serogroup 4 isolated from joint tissue.we report the isolation of legionella pneumophila serogroup 4 from synovial tissue obtained from an 80-year-old female with chronic swelling of her right metacarpophalangeal joint. synovial tissue infections caused by l. pneumophila are rare. interestingly, this isolate was recovered from chocolate agar after 5 days of incubation.200415004121
[pontiac fever--non-pneumonic legionellosis].pontiac fever is a non-pneumonic, epidemic form of legionellosis. the symptoms are similar to flu: fever, tiredness, myalgia, arthralgia, headache, cough, sore throat and nausea. the incubation period is from 30 to 90 hours, approx. 36 h., the attack rate is high: 70-90%. there are no differences in sex and age of ill people, the same number of women and men or children were affected. unfortunately, ill children symptoms might be differ: higher fever (40 c), lack of leukocytosis with left shift, ...200315029835
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