Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| amoebae as training grounds for intracellular bacterial pathogens. | 2005 | 15640165 | |
| legionella species diversity in an acidic biofilm community in yellowstone national park. | legionella species are frequently detected in aquatic environments, but their occurrence in extreme, acidic, geothermal habitats has not been explored with cultivation-independent methods. we investigated a predominately eukaryotic algal mat community in a ph 2.7 geothermal stream in yellowstone national park for the presence of legionella and potential host amoebae. our analyses, using pcr amplification with legionella-specific primers targeting 16s rrna genes, detected four known legionella sp ... | 2005 | 15640227 |
| the pneumoplex assays, a multiplex pcr-enzyme hybridization assay that allows simultaneous detection of five organisms, mycoplasma pneumoniae, chlamydia (chlamydophila) pneumoniae, legionella pneumophila, legionella micdadei, and bordetella pertussis, and its real-time counterpart. | respiratory disease caused by atypical bacteria remains an important cause of morbidity and mortality for adults and children, despite the widespread use of effective antimicrobials agents. culture remains the "gold standard" for the detection of these agents. however, culture is labor-intensive, takes several days to weeks for growth, and can be very insensitive for the detection of some of these organisms. newer singleplex pcr diagnostic tests are sensitive and specific, but multiple assays wo ... | 2005 | 15695646 |
| bioinformatics analysis of the locus for enterocyte effacement provides novel insights into type-iii secretion. | like many other pathogens, enterohaemorrhagic and enteropathogenic strains of escherichia coli employ a type-iii secretion system to translocate bacterial effector proteins into host cells, where they then disrupt a range of cellular functions. this system is encoded by the locus for enterocyte effacement. many of the genes within this locus have been assigned names and functions through homology with the better characterised ysc-yop system from yersinia spp. however, the functions and homologie ... | 2005 | 15757514 |
| antibacterial activities of gemifloxacin, levofloxacin, gatifloxacin, moxifloxacin and erythromycin against intracellular legionella pneumophila and legionella micdadei in human monocytes. | the antibacterial activity of a new fluoroquinolone, gemifloxacin, was tested against intracellular legionella pneumophila and legionella micdadei and was compared with the activities of levofloxacin, gatifloxacin, moxifloxacin and erythromycin. | 2005 | 15941776 |
| l. micdadei pve successfully treated with levofloxacin/valve replacement: case report and review of the literature. | prosthetic valve endocarditis (pve) due to legionella micdadei was diagnosed in a man a year after valve replacement with a bovine xenograft. he did not have pneumonia. the microbiologic diagnosis was established after valvectomy, which was necessitated by failure of empiric antibiotics to eradicate the infection. the fastidious organism grew only on buffered charcoal yeast extract agar and was confirmed as l. micdadei by gene sequence analysis. we believe this to be the first culture-proven cas ... | 2005 | 15996745 |
| development and evaluation of chlamylege, a new commercial test allowing simultaneous detection and identification of legionella, chlamydophila pneumoniae, and mycoplasma pneumoniae in clinical respiratory specimens by multiplex pcr. | this study describes the development and evaluation of a new commercial test, chlamylege (argene inc.), which allows the simultaneous detection in respiratory samples of chlamydophila pneumoniae, mycoplasma pneumoniae, and most legionella species, as well as pcr inhibitors, by using a multiplex pcr and microplate hybridization. the sensitivities of chlamylege were 1 x 10(-3) ifu, 5 x 10(-2) color-changing units, and 1 cfu per reaction tube for c. pneumoniae, m. pneumoniae, and legionella pneumop ... | 2005 | 16000443 |
| coevolution between nonhomologous but functionally similar proteins and their conserved partners in the legionella pathogenesis system. | legionella pneumophila, the causative agent of legionnaires' disease, and other pathogenic legionella species multiply inside protozoa and human macrophages by using the intracellular multiplication (icm)/defect in organelle trafficking (dot) type-iv secretion system. the icmq protein, which possesses pore-forming activity, and icmr, which regulates the icmq activity, are two essential components of this system. analysis of the region expected to contain these two genes from 29 legionella specie ... | 2005 | 16091472 |
| characterization of legionella pneumophila pmia, a gene essential for infectivity of protozoa and macrophages. | the ability of legionella pneumophila to cause pneumonia is dependent on intracellular replication within alveolar macrophages. the icm/dot secretion apparatus is essential for the ability of l. pneumophila to evade endocytic fusion, to remodel the phagosome by the endoplasmic reticulum (er), and to replicate intracellularly. protozoan and macrophage infectivity (pmi) mutants of l. pneumophila, which include 11 dot/icm mutants, exhibit defects in intracellular growth and replication within both ... | 2005 | 16177298 |
| in vitro activity of pazufloxacin, tosufloxacin and other quinolones against legionella species. | the activities of pazufloxacin and tosufloxacin against legionella spp. were evaluated in vitro and compared with those of other quinolones, macrolides and azithromycin. | 2005 | 16260445 |
| legionella confirmation using real-time pcr and syto9 is an alternative to current methodology. | the currently accepted culture techniques for the detection of legionella spp. in water samples (as/nzs 3896:1998 and iso 11731 standard methods) are slow and laborious, requiring from 7 to 14 days for a result. we describe a fully validated rapid confirmation technique that uses real-time pcr incorporating the intercalating dye syto9 for the direct identification of primary cultures, significantly decreasing turnaround time and allowing faster remedial action to be taken by the industry. | 2005 | 16332896 |
| [monitoring and control of opportunistic bacteria in a spa water used for aerosol hydrotherapy]. | a bicarbonate-sulphate-calcic water of a therapeutic spa was monitored for the presence of legionella, pseudomonas and mycobacteria. the water was analysed by taking samples from the well, the feed tank and from the final aerosol generating devices of two different water lines, the former at 21-23 degrees, the second at 36-38 degrees. the bacteria in question were always absent from the well. legionellae were found in the water of aerosol equipment: legionella micdadei was isolated from 75% of s ... | 2005 | 16353675 |
| 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. | 2004 | 15004121 |
| legionella micdadei infection presenting as severe secretory diarrhea and a solitary pulmonary mass. | sixty percent of infections with non-pneumophila species of legionella are caused by legionella micdadei. although diarrhea is a common symptom of legionellosis, including that due to l. micdadei infection, severe, life-threatening diarrhea is rare. we describe a patient with profound secretory diarrhea (secretion rate, up to 8 l/day) that was secondary to culture-proven l. micdadei pneumonia. in addition, a 3-cm pulmonary nodule was detected, which completely resolved after proper treatment for ... | 2004 | 15034849 |
| characterization of the alternative sigma factor sigma54 and the transcriptional regulator fleq of legionella pneumophila, which are both involved in the regulation cascade of flagellar gene expression. | we cloned and analyzed legionella pneumophila corby homologs of rpon (encoding sigma(54)) and fleq (encoding sigma(54) activator protein). two other genes (fler and pilr) whose products have a sigma(54) interaction domain were identified in the genome sequence of l. pneumophila. an rpon mutant strain was nonflagellated and expressed very small amounts of the flaa (flagellin) protein. like the rpon mutant, the fleq mutant strain of l. pneumophila was also nonflagellated and expressed only small a ... | 2004 | 15090493 |
| characterization of the icmh and icmf genes required for legionella pneumophila intracellular growth, genes that are present in many bacteria associated with eukaryotic cells. | legionella pneumophila, the causative agent of legionnaires' disease, replicates intracellularly within a specialized phagosome of mammalian and protozoan host cells, and the icm/dot type iv secretion system has been shown to be essential for this process. unlike all the other known icm/dot proteins, the icmf protein, which was described before, and the icmh protein, which is characterized here, have homologous proteins in many bacteria (such as yersinia pestis, salmonella enterica, rhizobium le ... | 2004 | 15155646 |
| legionella in two splenectomized patients. coincidence or causal relationship? | we describe two splenectomized patients admitted with pneumonia. the course in one was complicated by overwhelming multiorgan failure when the only indicative laboratory result was seropositivity for legionella hackeliae and legionella longbeachae. he was initially treated with ceftriaxone and roxithromycin, followed by levofloxacin as well as intensive supportive treatment, and survived. the second patient was seroreactive for legionella micdadei. in some cases of pneumonia in splenectomized pa ... | 2004 | 15188080 |
| legionella micdadei pneumonia diagnosed by culture isolation and dna-dna hybridization from bronchial lavage fluid. | an 80-year-old man was admitted because of dyspnea on effort. we suspected an acute exacerbation of chronic heart failure and idiopathic interstitial pneumonia caused by right-sided pneumonia. a nodular shadow in right upper lobe spread and consolidated into the airspace, and it failed to improve despite administration of meropenem trihydrate, vancomycin hydrochloride and clindamycin. a definitive diagnosis of legionella micdadei pneumonia was made on the basis of this organism being isolated in ... | 2004 | 15283188 |
| rapid detection and identification of human adenovirus species by adenoplex, a multiplex pcr-enzyme hybridization assay. | human adenoviruses (adv) have been implicated in a wide variety of diseases and are ubiquitous in populations worldwide. these agents are of concern particularly in immunocompromised patients, children, and military recruits, resulting in severe disease or death. clinical diagnosis of adv is usually achieved through routine viral cell culture, which can take weeks for results. immunofluorescence and enzyme-linked immunosorbent assay-based techniques are more timely but lack sensitivity. the abil ... | 2004 | 15364992 |
| [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, ... | 2003 | 15029835 |
| 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 ... | 2003 | 12517855 |
| 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 ... | 2003 | 12676871 |
| 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 ... | 2003 | 12734211 |
| 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. | 2003 | 12734286 |
| [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 ... | 2003 | 14984304 |
| legionnaires' disease - results of a multicentre canadian study. | there has never been a cross-canada surveillance project to determine the rate of legionella species as a cause of community-acquired pneumonia requiring hospitalization and to determine whether there are any regional differences in the rates of legionnaires' disease in canada. anecdotally, legionnaires' disease is thought to be uncommon in western canada. | 2003 | 18159449 |
| pregnancy and gamma/delta t cells: taking on the hard questions. | 2003 | 14651751 | |
| rapid identification of bacteria from positive blood cultures by terminal restriction fragment length polymorphism profile analysis of the 16s rrna gene. | bacteremia results in significant morbidity and mortality, especially among patient populations that are immunocompromised. broad-spectrum antibiotics are administered to patients suspected to have bloodstream infections that are awaiting diagnosis that depends on blood culture analysis. significant delays in identification of pathogens can result, primarily due to the dependence on growth-based identification systems. to address these limitations, we took advantage of terminal restriction fragm ... | 2003 | 12904391 |
| 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 ... | 2002 | 11914343 |
| 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. | 2002 | 12354888 |
| 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 ... | 2002 | 12364373 |
| 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. | 2002 | 12508793 |
| 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 ... | 2001 | 11119504 |
| 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 ... | 2001 | 11136765 |
| 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 ... | 2001 | 11148009 |
| 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 ... | 2001 | 11254553 |
| 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 ... | 2001 | 11254621 |
| 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 ... | 2001 | 11349975 |
| 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 ... | 2001 | 11401964 |
| 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 ... | 2001 | 11446394 |
| 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 ... | 2001 | 11500403 |
| 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 ... | 2001 | 11525995 |
| 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 ... | 2001 | 11527809 |
| 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 ... | 2001 | 11557455 |
| 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 ... | 2001 | 11571186 |
| 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 ... | 2001 | 11679917 |
| 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 ... | 2001 | 11724886 |
| [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. | 2000 | 11860816 |
| impact of antimicrobial agents and chemotherapy from 1972 to 1998. | 2000 | 10898668 | |
| 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 ... | 2000 | 10633110 |
| 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 ... | 2000 | 10671453 |
| 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 ... | 2000 | 10678909 |
| 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 ... | 2000 | 10722574 |
| 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 ... | 2000 | 10858211 |
| 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 ... | 2000 | 10878038 |
| 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 ... | 2000 | 10991843 |
| 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. | 2000 | 11014721 |
| nosocomial legionella micdadei infection in transplant patients: fortune favors the prepared mind. | 2000 | 11014731 | |
| 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 ... | 2000 | 11035756 |
| 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 ... | 2000 | 11040443 |
| 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 ... | 2000 | 11073936 |
| 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 ... | 2000 | 11083821 |
| [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. | 1999 | 10682546 |
| 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 ... | 1999 | 10361912 |
| 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 ... | 1999 | 10364593 |
| 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. ... | 1999 | 10388713 |
| 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 ... | 1999 | 10417184 |
| 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 ... | 1999 | 10488187 |
| 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 ... | 1999 | 9854105 |
| 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 ... | 1999 | 11856250 |
| 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 ... | 1999 | 10515901 |
| 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 ... | 1999 | 10542183 |
| 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 ... | 1999 | 10545255 |
| diagnosis of infectious diseases: a cytopathologist's perspective. | this review explores the role of the cytopathology laboratory in the detection and presumptive identification of microorganisms. sample procurement by exfoliation, abrasion, and aspiration techniques, as well as a variety of cytopreparatory and staining methods, is reviewed. emphasis is placed on the utility of fine-needle aspiration as a rapid, safe, and cost-effective diagnositic procedure. the role of rapid interpretation and specimen triage is also discussed. cytomorphologic features and sta ... | 1998 | 9564567 |
| [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 ... | 1998 | 9893432 |
| [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. | 1998 | 10322756 |
| 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 ... | 1998 | 9448158 |
| 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 ... | 1998 | 9495748 |
| 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 ... | 1998 | 9521144 |
| 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 ... | 1998 | 9529072 |
| 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 ... | 1998 | 9529113 |
| 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 ... | 1998 | 9533475 |
| 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 ... | 1998 | 9542962 |
| 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 ... | 1998 | 9596766 |
| 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 ... | 1998 | 9620377 |
| 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 ... | 1998 | 9636866 |
| 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 ... | 1998 | 9647849 |
| diagnosis of q fever. | 1998 | 9650920 | |
| 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 ... | 1998 | 9650941 |
| 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 ... | 1998 | 9705420 |
| 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 ... | 1998 | 9712761 |
| invasion of protozoa by legionella pneumophila and its role in bacterial ecology and pathogenesis. | 1998 | 9726849 | |
| 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 ... | 1998 | 9726850 |
| 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 ... | 1998 | 9826369 |
| 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 ... | 1998 | 10497650 |
| systemic lupus erythematosus: a risk factor for pneumonia caused by legionella micdadei? | 1997 | 9531245 | |
| 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 ... | 1997 | 9511064 |
| 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 ... | 1997 | 8996029 |
| 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 ... | 1997 | 9067657 |
| invasion of eukaryotic cells by legionella pneumophila: a common strategy for all hosts? | legionella pneumophila is an environmental micro-organism capable of producing an acute lobar pneumonia, commonly referred to as legionnaires' disease, in susceptible humans. legionellae are ubiquitous in aquatic environments, where they survive in biofilms or intracellularly in various protozoans. susceptible humans become infected by breathing aerosols laden with the bacteria. the target cell for human infection is the alveolar macrophage, in which the bacteria abrogate phagolysosomal fusion. ... | 1997 | 22514486 |