Publications

an unusual case of hospital-acquired infection: legionella longbeachae.		2009	19585301
the clinical efficacy of fluoroquinolone and macrolide combination therapy compared with single-agent therapy against community-acquired pneumonia caused by legionella pneumophila.		2009	19592113
genome-scale identification of legionella pneumophila effectors using a machine learning approach.	a large number of highly pathogenic bacteria utilize secretion systems to translocate effector proteins into host cells. using these effectors, the bacteria subvert host cell processes during infection. legionella pneumophila translocates effectors via the icm/dot type-iv secretion system and to date, approximately 100 effectors have been identified by various experimental and computational techniques. effector identification is a critical first step towards the understanding of the pathogenesis ...	2009	19593377
[low mortality rate in an outbreak of legionnaires' disease: correlation with the cytopathogenity study].	in 2001 an outbreak of legionnaires' diseases occurred in murcia, spain, with one of the lowest known rates of associated mortality. we describe the clinical data of a subgroup of patients, and present the results from molecular and virulence studies to correlate the lower mortality of the overall series with the strain virulence.	2009	19595380
[a case of legionella pneumonia with diabetic ketoacidosis rescued despite the development of acute renal failure and ards].	a 57-year-old man was admitted to our hospital complaining of general fatigue and appetite loss. the initial chest radiograph showed infiltration in the left upper lung field. cefozopran was administered. concomitant diabetic ketoacidosis was treated with hydration and rapid-acting insulin. however he was intubated and ventilated because of deteriorated respiratory condition and ketoacidosis on the 3rd hospital day. urinary legionella antigen was detected the same day, therefore ciprofloxacin an ...	2009	19601525
direct sequencing of legionella pneumophila from respiratory samples for sequence-based typing analysis.	we have developed a procedure to test the efficiency and reliability of sequencing of legionella pneumophila genes directly from respiratory samples and have compared the results with those derived from cultured isolates. we tried to obtain the nucleotide sequences of six protein-coding loci included in the sequence-based typing scheme for legionella pneumophila and three intergenic regions from 132 samples corresponding to 106 patients positive for urine antigen. a seminested pcr approach was u ...	2009	19605573
sequence-based and monoclonal antibody typing of legionella pneumophila isolated from patients in portugal during 1987-2008.	the monoclonal antibodies and the sequence-based typing (sbt) are two methodologies widely used to characterise legionella pneumophila strains serogroup 1 (sg1). in this study, we analysed the clinical strains received in two portuguese laboratories since 1987, including the strains isolated in portugal during the four years of the surveillance scheme for legionnaires' disease implemented in 2004. in total, 63 clinical isolates of l. pneumophila sg1 were differentiated by sbt into 19 different s ...	2009	19607780
legionella as a cause of hyperpyrexia.		2009	19619052
nosocomial legionellosis: prevention and management.	legionnaires' disease (ld) can be nosocomial, community acquired or travel related. the source of legionella infection is potable water systems that become colonized by the microorganism. prevention studies involved mainly hospital water systems. different strategies have been suggested but none are fully successful: engineering modifications, heating of water to temperatures above 59 degrees c, heating and flushing the plumbing with hot water (80 degrees c), water chlorination, silver-copper io ...	2009	19622057
mycotic aortic aneurysm associated with legionella anisa.	legionella anisa is rarely associated with human disease. its gene was identified by broad-range pcr in whole blood and excised tissue from a patient with a culture-negative mycotic aneurysm and was considered as a possible pathogen. this case report is potentially useful for the future diagnosis of intravascular infection.	2009	19458178
[using real-time polymerase chain reaction for detection of legionella in objects of the environment].	to assess efficacy of using the method of quantitative detection of legionella in objects of the environment by real-time polymerase chain reaction (rt-pcr).	2009	19459484
laboratory-based evaluation of legionellosis epidemiology in ontario, canada, 1978 to 2006.	legionellosis is a common cause of severe community acquired pneumonia and respiratory disease outbreaks. the ontario public health laboratory (ophl) has conducted most testing for legionella species in the canadian province of ontario since 1978, and represents a multi-decade repository of population-based data on legionellosis epidemiology. we sought to provide a laboratory-based review of the epidemiology of legionellosis in ontario over the past 3 decades, with a focus on changing rates of d ...	2009	19460152
comparison of clinical and environmental samples of legionella pneumophila at the nucleotide sequence level.	legionella pneumophila serogroup 1 is the most common etiological agent of legionellosis. we have used clinical and environmental isolates from different sources to compare their genetic variability. we have obtained the nucleotide sequence for six protein-coding loci, included in the sbt scheme for l. pneumophila, and three intergenic regions from 127 samples, 47 of environmental origin and 80 from clinical samples. levels of genetic variability were found to be higher in the environmental than ...	2009	19465160
free-living protozoa in two unchlorinated drinking water supplies, identified by phylogenic analysis of 18s rrna gene sequences.	free-living protozoan communities in water supplies may include hosts for legionella pneumophila and other undesired bacteria, as well as pathogens. this study aimed at identifying free-living protozoa in two unchlorinated groundwater supplies, using cultivation-independent molecular approaches. for this purpose, samples (<20 degrees c) of treated water, distributed water, and distribution system biofilms were collected from supply a, with a low concentration of natural organic matter (nom) (<0. ...	2009	19465529
bathwater-associated cases of legionellosis in japan, with a special focus on legionella concentrations in water.	to evaluate the relationship between the incidence of legionellosis and legionella concentrations in bathwater, we sent a questionnaire to 76 prefectural and municipal public health laboratories in japan and found that 35 had encountered cases of legionellosis and had implemented investigations to determine the sources of the infections. based on the results of the questionnaire, we were able to analyze various characteristics of the patients, of the facilities that were thought to be associated ...	2009	19468181
mutational paths towards increased fluoroquinolone resistance in legionella pneumophila.	fluoroquinolone resistance has been poorly studied in legionella pneumophila, an intracellular pathogen responsible for legionellosis. our goal was to further characterize molecular mechanisms involved in fluoroquinolone resistance in this species.	2009	19474069
phenotypic heterogeneity within microbial populations at the single-cell level investigated by confocal raman microspectroscopy.	single cells in genetically homogeneous microbial cultures exhibit marked phenotypic heterogeneity that is considered to bolster the fitness of the whole population. heterogeneity on the single-cell level is typically masked in conventional studies of microbial populations, which rely on data averaged across thousands or millions of cells in a sample. here we introduce confocal raman microspectroscopy as a method for investigating and illustrating the spatial heterogeneity of microbial cell popu ...	2009	19475141
region of elongation factor 1a1 involved in substrate recognition by legionella pneumophila glucosyltransferase lgt1: identification of lgt1 as a retaining glucosyltransferase.	lgt1 is one of the glucosyltransferases produced by the gram-negative bacterium legionella pneumophila. this enzyme modifies eukaryotic elongation factor 1a (eef1a) at serine 53, which leads to inhibition of protein synthesis and death of target cells. here we studied the region of eef1a, which is essential for substrate recognition by lgt1. we report that the decapeptide (50)gkgsfkyawv(59) of eef1a is efficiently modified by lgt1. this peptide covers the loop of the helix-loop-helix region form ...	2009	19478083
[legionella and legionnaires' disease: what do we know?]		2009	19481374
proteomic analysis of legionella-containing phagosomes isolated from dictyostelium.	legionella pneumophila, the agent of legionnaires' disease, replicates intracellularly within specialized phagosomes of human macrophages and amoebae. in this study, we have developed a protocol for the isolation of legionella-containing phagosomes from dictyostelium discoideum. cell fractionation, two-dimensional gel electrophoresis and maldi-tof ms combined with genomic data identified 157 phagosome host proteins. in addition to proteins with an evident role in phagosome maturation, we identif ...	2009	19482547
the antibacterial activity of fragrance ingredients against legionella pneumophila.	in the current study we investigated the antibacterial activity of fragrance ingredients against legionella pneumophila, a causative agent of severe pneumonia. among the 41 different fragrance ingredients tested, we found that the natural fragrance ingredients oakmoss (om) and birch tar oil (bt), which contain many components, exhibit potent antibacterial activity. the minimum inhibitory concentration (mic, % (v/v)) of om and bt were 0.0020 and 0.0024, respectively and were lower than that of ci ...	2009	19483326
contribution of phosphatidylserine to membrane surface charge and protein targeting during phagosome maturation.	during phagocytosis, the phosphoinositide content of the activated membrane decreases sharply, as does the associated surface charge, which attracts polycationic proteins. the cytosolic leaflet of the plasma membrane is enriched in phosphatidylserine (ps); however, a lack of suitable probes has precluded investigation of the fate of this phospholipid during phagocytosis. we used a recently developed fluorescent biosensor to monitor the distribution and dynamics of ps during phagosome formation a ...	2009	19487458
transcriptional down-regulation and rrna cleavage in dictyostelium discoideum mitochondria during legionella pneumophila infection.	bacterial pathogens employ a variety of survival strategies when they invade eukaryotic cells. the amoeba dictyostelium discoideum is used as a model host to study the pathogenic mechanisms that legionella pneumophila, the causative agent of legionnaire's disease, uses to kill eukaryotic cells. here we show that the infection of d. discoideum by l. pneumophila results in a decrease in mitochondrial messenger rnas, beginning more than 8 hours prior to detectable host cell death. these changes can ...	2009	19492077
potentially pathogenic amoeba-associated microorganisms in cooling towers and their control.	cooling towers provide a favorable environment for the proliferation of microorganisms. cooling towers generate a biofilm and often aerosolize contaminated water, thereby increasing the risk of microorganism dissemination by human inhalation. this pathogen dissemination was first revealed by the epidemics of legionnaires' disease that were directly related to the presence of cooling towers, and since then, the ecology of legionella pneumophila has been well studied. each country has specific sta ...	2009	19492970
severe concurrent lung infection caused by legionella and mycoplasma in a 3-year-old patient with down syndrome and tuberous sclerosis.		2009	19500283
legionella pneumophila goes clonal--paris and lorraine strain-specific risk factors.		2009	19508166
host-related risk factors and clinical features of community-acquired legionnaires disease due to the paris and lorraine endemic strains, 1998-2007, france.	in france, legionnaires disease is mainly caused by legionella pneumophila. here, we investigated possible host factors associated with susceptibility to community-acquired legionnaires disease caused by the endemic paris and lorraine strains.	2009	19508168
modulation of membrane traffic between endoplasmic reticulum, ergic and golgi to generate compartments for the replication of bacteria and viruses.	several bacteria and viruses remodel cellular membranes to form compartments specialised for replication. bacteria replicate within inclusions which recruit membrane vesicles from the secretory pathway to provide nutrients for microbial growth and division. viruses generate densely packed membrane vesicles called viroplasm which provide a platform to recruit host and viral proteins necessary for replication. this review describes examples where both intracellular bacteria (salmonella, chlamydia ...	2009	19508853
[case of legionella pneumonia caused by a household humidifier].	a 60-year-old-man with diabetes mellitus was admitted to our hospital because of pyrexia of up to 40 degrees and dyspnea. chest radiograph revealed ground glass infiltrates in both lung fields. legionella pneumonia was diagnosed as a consequence of the urinary examination performed for legionella antigen detection; further, we initiated intravenous pazufloxacin administration. despite an antibiotic, sivelestat sodium, and mechanical ventilation, the condition of the patient worsened and he died ...	2009	19514500
[topical aspects of hot water supply to the population].	the aspects of hot water supply, which determine the safety of hot water delivered to the population, are considered. the authors underline the antiepidemic value of hot water temperature maintenance at the water pumping points of not below 60 degrees c as only this measure liably prevents water multiplication of legionella pneumophila that induces legionellosis, a severe disease, as well as other high temperature-resistant microorganisms. the results of estimating the residential use of hot wat ...	2009	19517595
[atypical and opportunistic pulmonary infections after cardiac surgery].	new diseases and therapies that lead to marked immunocompromise, have brought to medicine so-called opportunistic infections, caused by pathogens that usually do not cause disease in the presence of a healthy immune system. first diagnosed in aids patients, opportunistic infections have appeared in many other situations, including transplant recipients, other immunosuppressed patients, and even in otherwise healthy patients undergoing major elective surgery. among the most common pathogens causi ...	2009	19517677
chemical structure and biological significance of lipopolysaccharide from legionella.	legionella are aerobic, gram-negative, motile, rod-shaped bacteria, which form a distinct taxonomic unit within the gamma - 2 subdivision of the proteobacteria. the reservoirs of legionella are natural or man-made water systems where the bacteria survive and disseminate as obligate intracellular parasites of free living protozoa. in the human lung, the bacteria invade alveolar macrophages inducing the potentially lethal pneumonia commonly known as legionnaires' disease. although all legionella s ...	2009	19519544
dynamics of legionella antibody levels during 1 year in a healthy population.	a total of 522 danish blood donors were followed during 2004-2005 to describe the seroepidemiology of legionella infections in healthy individuals from a general population. antibodies to legionella spp. were measured by indirect immunofluorescence antibody test. the prevalence of legionella antibodies (titre 1:128) was 26.8% and remained fairly constant during the year of follow-up. however, 6.9% of the blood donors developed a fourfold or greater rise in antibody titres. a history of visits to ...	2009	19102798
surface translocation by legionella pneumophila: a form of sliding motility that is dependent upon type ii protein secretion.	legionella pneumophila exhibits surface translocation when it is grown on a buffered charcoal yeast extract (bcye) containing 0.5 to 1.0% agar. after 7 to 22 days of incubation, spreading legionellae appear in an amorphous, lobed pattern that is most manifest at 25 to 30 degrees c. all nine l. pneumophila strains examined displayed the phenotype. surface translocation was also exhibited by some, but not all, other legionella species examined. l. pneumophila mutants that were lacking flagella and ...	2009	19114479
legionella pollution in cooling tower water of air-conditioning systems in shanghai, china.	to determine legionella pollution prevalence, describe the amount of legionellae with respect to temperature in shanghai cooling tower water (ctws) in various types of public sites.	2009	19120608
the efficacy of biocides and other chemical additives in cooling water systems in the control of amoebae.	in vitro experiments were undertaken to evaluate biocide formulations commonly used in cooling water systems against protozoa previously isolated from cooling towers. the investigations evaluated the efficacy of these formulations against amoebic cysts and trophozoites.	2009	19187130
biofilm problems in dental unit water systems and its practical control.	dental chair units (dcus) contain integrated systems that provide the instruments and services for a wide range of dental procedures. dcus use water to cool and irrigate dcu-supplied instruments and tooth surfaces during dental treatment. water is supplied to these instruments by a network of interconnected narrow-bore (2-3 mm) plastic tubes called dental unit waterlines (duwls). many studies over the last 40 years demonstrated that duwl output water is often contaminated with high densities of ...	2009	19187140
stopping legionella in its tracks.	recent legionella outbreaks have done nothing to reassure the general public and "customers" of the healthcare sector that there is no risk from the disease. here jo welters, microbiologist and sector head of ta-aqua+ at hydronic balancing specialist tour & andersson, discusses the relevance of a new method for tackling legionella prevention and the means of removing the current risks associated with the bacteria.	2009	19192600
asc and ipaf inflammasomes direct distinct pathways for caspase-1 activation in response to legionella pneumophila.	caspase-1 activation is a key feature of the innate immune response of macrophages elicited by pathogens and a variety of toxins. here, we determined the requirement for different adapter proteins involved in regulating host processes mediated by caspase-1 after macrophage infection by legionella pneumophila. the adapter protein asc was found to be important for caspase-1 activation during l. pneumophila infection. activation of caspase-1 through asc did not require the flagellin-sensing pathway ...	2009	19237518
incorporation of natural uncultivable legionella pneumophila into potable water biofilms provides a protective niche against chlorination stress.	legionella pneumophila is a waterborne pathogen that has been isolated sporadically from drinking water distribution systems (dwds). resistance to disinfectants is mainly attributed to the association of cells with amoebae, but biofilms are also thought to provide some degree of protection. in the present work, a two-stage chemostat was used to form heterotrophic biofilms from drinking water to study the influence of chlorine on the presence of naturally occurring l. pneumophila. the pathogen wa ...	2009	19241230
comparison between standard culture and peptide nucleic acid 16s rrna hybridization quantification to study the influence of physico-chemical parameters on legionella pneumophila survival in drinking water biofilms.	legionella pneumophila is a waterborne pathogen that is mainly transmitted by the inhalation of contaminated aerosols. in this article, the influence of several physico-chemical parameters relating to the supply of potable water was studied using a l. pneumophila peptide nucleic acid (pna) specific probe to quantify total l. pneumophila in addition to standard culture methods. a two-stage chemostat was used to form the heterotrophic biofilms, with biofilm generating vessels fed with naturally oc ...	2009	19241231
twitching motility in legionella pneumophila.	twitching motility is a form of bacterial translocation over solid or semi-solid surfaces mediated by the extension, tethering, and subsequent retraction of type iv pili. these pili are also known to be involved in virulence, biofilm formation, formation of fruiting bodies, horizontal gene transfer, and protein secretion. we have characterized the presence of twitching motility on agar plates in legionella pneumophila, the etiological agent of legionnaires' disease. by examining twitching motili ...	2009	19243440
a type ii secreted rnase of legionella pneumophila facilitates optimal intracellular infection of hartmannella vermiformis.	type ii protein secretion plays a role in a wide variety of functions that are important for the ecology and pathogenesis of legionella pneumophila. perhaps most dramatic is the critical role that this secretion pathway has in l. pneumophila intracellular infection of aquatic protozoa. recently, we showed that virulent l. pneumophila strain 130b secretes rnase activity through its type ii secretion system. we now report the cloning and mutational analysis of the gene (srna) encoding that novel t ...	2009	19246759
[comparison of five commercial assays for the detection of legionella pneumophila antigens in urine].	antigenuria detection is the main approach for diagnosing legionella infections. the aim of this study was to compare 5 commercially available methods for detecting legionella pneumophila soluble antigens in urine.	2009	19254639
identification of legionella species by use of an oligonucleotide array.	the genus legionella contains a diverse group of motile, asaccharolytic, nutritionally fastidious gram-negative rods. legionella pneumophila is the most important human pathogen, followed by l. micdadei, l. longbeachae, l. dumoffii, and other rare species. accurate identification of legionella spp. other than l. pneumophila is difficult because of biochemical inertness and phenotypic identity of different species. the feasibility of using an oligonucleotide array for identification of 18 species ...	2009	19261788
determination of legionella pneumophila susceptibility to melaleuca alternifolia cheel (tea tree) oil by an improved broth micro-dilution method under vapour controlled conditions.	the aim of this study was to determine the in vitro activity of melaleuca alternifolia cheel (tea tree) oil (tto) against 22 strains of legionella pneumophila of different serogroup and source of isolation. both a standard broth micro-dilution method, with slight modifications, and a micro-atmosphere diffusion method were used. furthermore, we have established a simple sealing procedure in the micro-dilution method to determine the antibacterial activity of tto against legionella in aqueous phas ...	2009	19264101
respiratory failure at home after coronary artery bypass graft surgery requiring extracorporeal membrane oxygenation.		2009	19264514
[inspection on legionella pollution and the health impact of workers in public places of central air conditioning systems in dalian city].	to inspect the conditions of legionella pollution in cooling towers of central air conditioning systems and the state of legionella potential infection of workers in public places in dalian city in order to study the impact factors related witb legiondlla organism infection.	2009	19267082
polymerase chain reaction for pathogen identification in persistent pediatric cervical lymphadenitis.	to study routine culture-negative persistent cervical lymphadenitis in children treated surgically during a 10-year period (december 26, 1997, to october 1, 2007) at a single institution.	2009	19289701
overview of diagnostic and detection methods for legionellosis and legionella spp.	since 1977, the diagnostic tools for legionnaires' disease have been based on culture and serological investigations. both methods require considerable time to produce results and have 'low' to 'reasonable' sensitivity. since the introduction of urinary antigen tests in the mid 1990s, underdiagnosis has diminished and mortality has declined, thanks to early diagnosis. to obtain the most accurate diagnosis, culture, serological investigation, and urinary antigen testing should all be performed. i ...	2009	19291209
bacterial fic proteins amp up infection.	proteins containing fic (filamentation induced by cyclic adenosine monophosphate) domains are found in both prokaryotic and eukaryotic organisms, but their function has remained elusive. recent studies indicate that bacterial fic domain-containing proteins disrupt host cell processes after being delivered into eukaryotic host cells: the vibrio parahaemolyticus vops protein interferes with rho guanine triphosphatase (gtpase) function, and the legionella pneumophila ankx protein disrupts the micro ...	2009	19293428
early and late treatment failure in community-acquired pneumonia.	treatment failure is a matter of great concern in the management of community-acquired pneumonia (cap). defined generally as lack of response or clinical deterioration, failure is considered early when it occurs within the first 72 hours and late when it occurs after 72 hours. the reported incidence of treatment failure among hospitalized patients with cap ranges from 2.4 to 31% for early failure and from 3.9 to 11% for late failure. most cases of early failure occur because of inadequate host-p ...	2009	19296415
atypical bacterial pathogens in community-acquired pneumonia in children: a hospital-based study.	a total of 243 children aged one month to five years with world health organization defined severe community acquired pneumonia were studied for the presence of atypical bacterial pathogens: 24 were found positive for mycoplasma infection. there was no significant association with any of the clinical, laboratory and radiological variables in children with pneumonia by the atypical pathogen.	2009	19299299
legionella pneumonia and use of the legionella urinary antigen test.		2009	19301376
the role of biofilms and protozoa in legionella pathogenesis: implications for drinking water.	current models to study legionella pathogenesis include the use of primary macrophages and monocyte cell lines, various free-living protozoan species and murine models of pneumonia. however, there are very few studies of legionella spp. pathogenesis aimed at associating the role of biofilm colonization and parasitization of biofilm microbiota and release of virulent bacterial cell/vacuoles in drinking water distribution systems. moreover, the implications of these environmental niches for drinki ...	2009	19302312
development and evaluation of a multiplex test for the detection of atypical bacterial dna in community-acquired pneumonia during childhood.	an incorrect or late diagnosis can lead to an increase in the morbidity and mortality caused by pneumonia, and the availability of a rapid and accurate microbiological test to verify the aetiology is imperative. this study evaluated a molecular test for the identification of the bacterial cause of atypical community-acquired pneumonia (acap). fifty-four children with pneumonia were studied using bacteriological cultures, mycoplasma pneumoniae, coxiella burnetii, chlamydophila pneumoniae and legi ...	2009	19302698
management in the emergency room of patients requiring hospital treatment of community-acquired pneumonia.	to identify factors influencing decisions in initial management of community-acquired pneumonia (cap) admitted to hospital through emergency departments.	2009	19308740
an outbreak of human metapneumovirus infection in hospitalized psychiatric adult patients in taiwan.	human metapneumovirus (hmpv) is a paramyxovirus that is associated with respiratory tract infection (rti) mostly in children, but these outbreaks have rarely been reported in adults. we encountered an outbreak of this disease involving 10 adults in a psychiatric ward in eastern taiwan. the nasopharyngeal swab specimens from 13 patients with symptoms of rti were obtained and analyzed. the rt-pcr tests were negative to influenza virus a/b, adenovirus, rsv, parainfluenza virus, coronavirus, nipah v ...	2009	19308801
systematic review and metaanalysis: urinary antigen tests for legionellosis.	urinary antigen assays offer simplicity and rapidity in diagnosing legionnaires' disease, though studies report a range of sensitivities. we conducted a systematic review to assess the test characteristics of legionella urinary antigen.	2009	19318671
pseudo-outbreak of legionella pneumophila serogroup 8 infection associated with a contaminated ice machine in a bronchoscopy suite.	to investigate the marked increase noted over an 8-month period in the number of legionella pneumophila isolates recovered from bronchoalveolar lavage fluid specimens obtained during bronchoscopy in our healthcare system.	2009	19320573
pkc(alpha) and pkc(epsilon) differentially regulate legionella pneumophila-induced gm-csf.	legionella pneumophila is an important causative agent of severe pneumonia in humans. the human alveolar epithelium is an effective barrier for inhaled microorganisms and actively participates in the initiation of innate host defense. although secretion of granulocyte-macrophage colony-stimulating factor (gm-csf) is essential for the elimination of invading legionella spp., mechanisms of legionella pneumophila-induced release of this cytokine are widely unknown. in this study, we have demonstrat ...	2009	19324950
evidence that the intra-amoebal legionella drancourtii acquired a sterol reductase gene from eukaryotes.	free-living amoebae serve as a natural reservoir for some bacteria that have evolved into "amoeba-resistant" bacteria. among these, some are strictly intra-amoebal, such as candidatus "protochlamydia amoebophila" (candidatus "p. amoebophila"), whose genomic sequence is available. we sequenced the genome of legionella drancourtii (l. drancourtii), another recently described intra-amoebal bacterium. by comparing these two genomes with those of their closely related species, we were able to study t ...	2009	19327142
caspase-7 activation by the nlrc4/ipaf inflammasome restricts legionella pneumophila infection.	legionella pneumophila (l. pneumophila), the causative agent of a severe form of pneumonia called legionnaires' disease, replicates in human monocytes and macrophages. most inbred mouse strains are restrictive to l. pneumophila infection except for the a/j, nlrc4(-/-) (ipaf(-/-)), and caspase-1(-/-) derived macrophages. particularly, caspase-1 activation is detected during l. pneumophila infection of murine macrophages while absent in human cells. recent in vitro experiments demonstrate that cas ...	2009	19343209
"my foot hurts": a flare of rheumatoid arthritis?	a 56-year-old man with a history of rheumatoid arthritis presented with a 2-day history of worsening pain in his left foot. treatment with high-dose steroids was of no benefit, hence a diagnosis of septic arthritis was considered. however, the patient's condition deteriorated despite empirical antibiotic therapy. following persistent investigation, the cause was identified as a fastidious legionella longbeachae infection, and appropriate antibiotic therapy led to complete resolution of the sepsi ...	2009	19351317
impact of the legionella urinary antigen test on epidemiological trends in community outbreaks of legionellosis in catalonia, spain, 1990-2004.	to describe the characteristics of community outbreaks of legionellosis in catalonia, spain from 1990 to 2004, to compare two time periods (1990-1996 and 1997-2004), and to assess the influence of outbreak characteristics on the case fatality rate (cfr).	2009	19356959
[detection of legionella in water and other environmental objects].		2009	19358362
viability pcr, a culture-independent method for rapid and selective quantification of viable legionella pneumophila cells in environmental water samples.	pcr-based methods have been developed to rapidly screen for legionella pneumophila in water as an alternative to time-consuming culture techniques. however, these methods fail to discriminate between live and dead bacteria. here, we report a viability assay (viability pcr [v-pcr]) for l. pneumophila that combines ethidium monoazide bromide with quantitative real-time pcr (qpcr). the ability of v-pcr to differentiate viable from nonviable l. pneumophila cells was confirmed with permeabilizing age ...	2009	19363080
legionella, protozoa, and biofilms: interactions within complex microbial systems.	currently, the investigation of legionella ecology falls into two distinct areas of research activity: (1) that legionella multiply within water sources by parasitizing amoebic or ciliate hosts or (2) that legionella grows extracellularly within biofilms. less focus has been given to the overlaps that may occur between these two areas or the likelihood that legionella employs multiple survival strategies to persist in water sources. it is likely that legionella interacts with protozoa, bacteria, ...	2009	19365668
structure and function of interacting icmr-icmq domains from a type ivb secretion system in legionella pneumophila.	during infection, legionella pneumophila creates a replication vacuole within eukaryotic cells and this requires a type ivb secretion system (t4bss). icmq plays a critical role in the translocase and associates with icmr. in this paper, we show that the n-terminal domain of icmq (qn) mediates self-dimerization, whereas the c-terminal domain with a basic linker promotes membrane association. in addition, the binding of icmr to icmq prevents self-dimerization and also blocks membrane permeabilizat ...	2009	19368892
pcr-based 'serotyping' of legionella pneumophila.	currently, several pcr assays based on 16s rrna and virulence-associated genes are available for detection of legionella pneumophila. so far, no genotyping method has been published that can discriminate between serogroups and monoclonal subgroups of the most common l. pneumophila serogroup 1. our first approach was to analyse lps-associated genes of seven l. pneumophila serogroup 1 strains, and we developed two pcr-based methods specific for serogroup 1. specific dna fragments could be amplifie ...	2009	19369520
antimicrobial mechanisms of phagocytes and bacterial evasion strategies.	professional phagocytes have a vast and sophisticated arsenal of microbicidal features. they are capable of ingesting and destroying invading organisms, and can present microbial antigens on their surface, eliciting acquired immune responses. to survive this hostile response, certain bacterial species have developed evasive strategies that often involve the secretion of effectors to co-opt the cellular machinery of the host. in this review, we present an overview of the antimicrobial defences of ...	2009	19369951
going with the flow: legionellosis risk in toronto, canada is strongly associated with local watershed hydrology.	legionella species are increasingly recognized as a cause of both healthcare- and community-acquired pneumonia (so-called "legionnaire's disease"). these pathogens are ubiquitous in the environment, but environmental factors in the occurrence of sporadic legionellosis remain poorly understood. we analyzed all legionellosis cases identified in the greater toronto area of ontario from 1978 to 2006, and evaluated seasonal and environmental patterns in legionellosis case occurrence by using both neg ...	2009	19370300
diagnostic and therapeutic challenges.		2009	19373127
the rapid and specific real-time detection of legionella pneumophila in water samples using optical waveguide lightmode spectroscopy.	the detection of legionella pneumophila in water samples using standard microbiological culture techniques is both prolonged and problematic. the bacterium is slow-growing and nutritionally fastidious, such that other indigenous species can out-compete the legionella even when using antibiotic supplemented media. optical waveguide lightmode spectroscopy (owls) is a real-time analytical system whereby a change to a higher coupling angle where the refractive index of a bacterial cell is higher tha ...	2009	19376163
is driving a car a risk for legionnaires' disease?	legionnaires' disease (ld) is a major cause of severe community-acquired pneumonia but the source and mode of transmission are not always apparent, especially in sporadic cases. we hypothesized that ld can be acquired from the air-conditioning systems of motor cars. swabs were taken from the evaporator compartments of the air-conditioning system of scrapped cars. healthy subjects who were mainly employees of regional transportation companies were tested for antibody to legionella pneumophila ser ...	2009	19379540
pseudomonas aeruginosa las quorum sensing autoinducer suppresses growth and biofilm production in legionella species.	bacteria commonly communicate with each other by a cell-to-cell signalling mechanism known as quorum sensing (qs). recent studies have shown that the las qs autoinducer n-(3-oxododecanoyl)-l-homoserine lactone (3-oxo-c(12)-hsl) of pseudomonas aeruginosa performs a variety of functions not only in intraspecies communication, but also in interspecies and interkingdom interactions. in this study, we report the effects of pseudomonas 3-oxo-c(12)-hsl on the growth and suppression of virulence factors ...	2009	19383702
[identification of legionella spp. by means of cultural and molecular methods in a public hospital].	an epidemiologic study on the isolation of legionella spp from the sanitary water of a public hospital in cagliari (italy) has been performed. the aim of the study was the comparison between the isolation of various legionella spp from different hospital sources and the real hazard of legionella infection of the inpatients. two test methods were used for legionella detection: a) the culture on selective media, that has the disadvantage of being quite time-consuming and of isolating also other ba ...	2009	19385336
targeting eef1a by a legionella pneumophila effector leads to inhibition of protein synthesis and induction of host stress response.	the legionella pneumophila dot/icm type iv secretion system is essential for the biogenesis of a phagosome that supports bacterial multiplication, most likely via the functions of its protein substrates. recent studies indicate that fundamental cellular processes, such as vesicle trafficking, stress response, autophagy and cell death, are modulated by these effectors. however, how each translocated protein contributes to the modulation of these pathways is largely unknown. in a screen to search ...	2009	19386084
pneumonia due to legionella feeleii: case report and review of the literature.	legionella feeleii is a rare cause of community-acquired pneumonia that occurs in immunocompromised hosts who are often receiving corticosteroid therapy. we report a 69-year-old man who underwent bone marrow transplantation and developed pneumonia due to l. feeleii, and review the clinical characteristics of 7 cases of l. feeleii infection reported in the literature.	2009	19392730
commercial potting soils as an alternative infection source of legionella pneumophila and other legionella species in switzerland.	legionella spp. are pathogens that can cause legionnaires' disease in humans through inhalation of contaminated aerosols. the principal reservoir for these microorganisms is water, but legionella spp. have been isolated from composted vegetable and plant material, and from many potting mixes as well. in australia, there have been several cases of legionnaires' disease in which legionella longbeachae has been isolated from potting soils. in switzerland, the source of infection cannot always be id ...	2009	19392903
purification of legiobactin and importance of this siderophore in lung infection by legionella pneumophila.	when cultured in a low-iron medium, legionella pneumophila secretes a siderophore (legiobactin) that is both reactive in the chrome azurol s (cas) assay and capable of stimulating the growth of iron-starved legionellae. using anion-exchange high-pressure liquid chromatography (hplc), we purified legiobactin from culture supernatants of a virulent strain of l. pneumophila. in the process, we detected the ferrated form of legiobactin as well as other cas-reactive substances. purified legiobactin h ...	2009	19398549
autophagy induced by 2-deoxy-d-glucose suppresses intracellular multiplication of legionella pneumophila in a/j mouse macrophages.	legionella pneumophila philadelphia-1 (lp-1) can grow intracellularly in a/j mouse peritoneal macrophages (a/j mphi). we previously reported that 2-deoxy-d-glucose (2dg), when added in macrophage culture medium, inhibited the intracellular multiplication of lp-1 in a/j mphi. we found that 1 mm of 2dg causes lc3-ii-conversion that reflects an induction of autophagy and that 1 and 10 mm of 2dg induced apoptosis associated with caspase-4 activation. we therefore investigated whether 2dg-induced aut ...	2009	19398893
two small ncrnas jointly govern virulence and transmission in legionella pneumophila.	to transit from intra- to extracellular environments, legionella pneumophila differentiates from a replicative/non-virulent to a transmissive/virulent form using the two-component system leta/lets and the global repressor protein csra. while investigating how both regulators act co-ordinately we characterized two ncrnas, rsmy and rsmz, that link the leta/lets and csra regulatory networks. we demonstrate that leta directly regulates their expression and show that rsmy and rsmz are functional in e ...	2009	19400772
the leta-rsmyz-csra regulatory cascade, together with rpos and pmra, post-transcriptionally regulates stationary phase activation of legionella pneumophila icm/dot effectors.	legionella pneumophila utilize the icm/dot type-iv secretion system to translocate effector proteins into host cells. some of these effectors were shown before to be regulated at the transcriptional level by the pmrab and cpxra two-component systems. in addition, the stationary phase-related regulators leta and csra, which are both members of the same post-transcriptional regulatory cascade, were shown to be involved in l. pneumophila virulence. in this report, we identified two small non-coding ...	2009	19400807
impact of biocide treatments on the bacterial communities of the lascaux cave.	the lascaux cave contains a remarkable set of paintings from the upper palaeolithic. shortly after discovery in 1940, the cave was modified for public viewing and, in 2001, was invaded by a fusarium solani species complex. benzalkonium chloride was used from 2001 to 2004 to eliminate the fungal outbreak. in this study, we carried out a sampling in most of the cave halls and galleries. sequence analysis and isolation methods detected that the most abundant genera of bacteria were ralstonia and ps ...	2009	19404600
treatment strategies for legionella infection.	given the nonspecific clinical manifestations of legionnaires' disease and the high mortality of untreated legionnaires' disease, we recommend routine use of legionella testing, especially the legionella urinary antigen test, for all patients with community-acquired pneumonia. this includes patients with ambulatory pneumonia and hospitalized children. legionella cultures should be more widely available, especially in hospitals where the drinking water is colonized with legionella. azithromycin o ...	2009	19405787
the coxiella burnetii ankyrin repeat domain-containing protein family is heterogeneous, with c-terminal truncations that influence dot/icm-mediated secretion.	coxiella burnetii is an obligate intracellular bacterium that directs biogenesis of a parasitophorous vacuole (pv) for replication. effectors of pv maturation are likely translocated into the host cytosol by a type iv secretion system (t4ss) with homology to the dot/icm apparatus of legionella pneumophila. since secreted bacterial virulence factors often functionally mimic the activities of host proteins, prokaryotic proteins with eukaryotic features are considered candidate t4ss substrates. gen ...	2009	19411324
bdha-patd operon as a virulence determinant, revealed by a novel large-scale approach for identification of legionella pneumophila mutants defective for amoeba infection.	legionella pneumophila, the causative agent of legionnaires' disease, is an intracellular parasite of eukaryotic cells. in the environment, it colonizes amoebae. after being inhaled into the human lung, the bacteria infect and damage alveolar cells in a way that is mechanistically similar to the amoeba infection. several l. pneumophila traits, among those the dot/icm type ivb protein secretion machinery, are essential for exploiting host cells. in our search for novel legionella virulence factor ...	2009	19411431
conjugative plasmid pld-tex-kl promotes growth of host bacterium legionella dumoffii at low temperatures.	legionella (fluoribacter) dumoffii is a resident of various aquatic environments and occasionally causes pneumonia in humans. we found that l. dumoffii strain tex-kl carries a 66-kb circular plasmid. as predicted by the presence of tra genes similar to those of other transferable plasmids, we showed that pld-tex-kl was actually capable of transferring itself to a plasmid-cured derivative of the original strain. unexpectedly, this plasmid-free derivative turned out to be partially defective in te ...	2009	19415237
evaluation of the oxoid xpect legionella test kit for detection of legionella pneumophila serogroup 1 antigen in urine.	we evaluated a new immunochromatographic assay (oxoid xpect legionella test kit) for the ability to detect legionella pneumophila serogroup 1 antigen in urine. the results were compared with those obtained with the binax now urinary antigen test by following the manufacturers' instructions. the sensitivities and specificities were estimated to be 89 and 100%, respectively, for the oxoid xpect legionella test kit and 86 and 100%, respectively, for the binax now test.	2009	19420163
travel-associated legionnaires disease in europe in 2007.	nine hundred and forty six cases of travel-associated legionnaires disease were reported to the european surveillance scheme for travel associated legionnaires disease (ewglinet) with onset during 2007; 890 were confirmed and 56 were presumptive. twenty eight cases died, giving a case fatality rate of 3.0%. 8.2% of cases were diagnosed by culture, an important increase from 5.2% in 2006. one hundred and twelve new clusters were identified; the largest involved nine cases. sixteen of these cluste ...	2009	19422777
suspected legionella-induced perimyocarditis in an adult in the absence of pneumonia: a rare clinical entity.	legionella infection can manifest itself in many clinical forms, most commonly as pneumonia, but rarely in the form of myocardial involvement. legionella with myocardial involvement independent of pneumonia is almost never seen in the adult population and therefore is cited only a handful of times in the medical literature. when reported, legionella carditis itself typically occurs as an isolated pericarditis with effusion. cases of isolated legionella with myocardial involvement, but without as ...	2009	20069090
[radiologic manifestations of legionnaire's disease].		2009	20058333
[investigation on strains of legionella pneumophila, isolated from a hospital of milano, with three genotyping methods].	various techniques have been developed in recent years for the molecular typing of microorganisms. remains particularly difficult to isolate clinical strains for the low availability of cases and even more problematic matching clinical / environmental strains. we investigated 13 strains of legionella pneumophila of clinical and environmental origin, isolated in 3 health facilities in milan (2003-2006), using three molecular typing methods: pulse-field gel electrophoresis, amplified fragment leng ...	2009	20058542
severe legionnaires disease complicated by multi-organ dysfunction in a previously healthy patient: a case report.	a case of a previously healthy lady with community-acquired pneumonia who progressed to severe acute respiratory distress syndrome, acute renal failure, disseminated intravascular coagulation and sepsis is reported. treatment with antibiotics and various modes of mechanical ventilation in the intensive care unit were successful. a urinary legionella antigen test was positive for legionella pneumophila.	2009	20062668
[modern conception of organization of epidemiological surveillance for legionella infections].	evolution of views on legionellosis is analyzed in the review: from extremely dangerous rare infection to sufficiently widespread severe pneumonia emergence of which is determined by features of ecology and prevalence of natural water microorganism in potentially dangerous water systems created by man. epidemiologic features of 3 main groups of legionellosis determined according to place of acquisition are discussed: sporadic (community-acquired) legionellosis; nosocomial legionellosis; legionel ...	2009	20063800
rabgdi displacement by drra from legionella is a consequence of its guanine nucleotide exchange activity.	prenylated rab proteins exist in the cytosol as soluble, high-affinity complexes with gdi that need to be disrupted for membrane attachment and targeting of rab proteins. the legionella pneumophila protein drra displaces gdi from rab1:gdi complexes, incorporating rab1 into legionella-containing vacuoles and activating rab1 by exchanging gdp for gtp. here, we present the crystal structure of a complex between the gef domain of drra and rab1 and a detailed kinetic analysis of this exchange. drra e ...	2009	20064470
disinfection of the hospital water supply: a hidden risk to dialysis patients.	water suitable for drinking is unsuited for use in the preparation of haemodialysis fluid and undergoes additional treatment. the primary component of the additional treatment is reverse osmosis, which does not remove low-molecular-weight contaminants, and the water treatment system must contain carbon beds or filters to ensure effective removal of such contaminants. the recent article by bek and colleagues highlights an unrecognised issue with respect to chemicals that may be added to the water ...	2009	20053299
[novel model of replicative legionella pneumophila lung infection in dba/2 mice].	we present here a new model of legionella pneumophila lung infection in dba/2 mice. by intranasal inoculation with 106 colony-forming units of l. pneumophila strain suzuki serogoup 1, persistent non-lethal lung infection was established as reflected by the detection of more than 10(4) cfu/lung of the organism 14 days after infection. treatment of mice with cyclophosphamide before infection enhanced bacterial replication in the lungs and all cyclophosphamide-treated mice experienced lethal infect ...	2009	20055121
[therapeutic efficacy of levofloxacin against a model of replicable legionella pneumophila lung infection in dba/2 mice].	the in vitro and in vivo antibacterial activities of levofloxacin (lvfx), a quinolone antibacterial, against clinically isolated legionella pneumophila were investigated in comparison with those of existing antimicrobial agents approved for legionnaires disease. the minimum inhibitory concentrations (mics) of the agents against 42 strains of l. pneumophila isolated in japan were determined using agar dilution methods with buffered starch yeast extract agar. mic90 of lvfx was 0.03 microg/ml and t ...	2009	20055122