| ambulatory patients with community-acquired pneumonia: the frequency of atypical agents and clinical course. | to determine the etiology of community-acquired pneumonia in patients treated in an ambulatory setting, using serological methods, and to compare presenting symptoms, radiographic manifestations, and clinical outcomes of patients with pneumonia of "atypical" and undetermined etiology. | 1996 | 8948274 |
| an oxaloacetate decarboxylase homologue protein influences the intracellular survival of legionella pneumophila. | legionella pneumophila is a facultative intracellular parasite which is able to survive in various eukaryotic cells. we characterised a tn5-mutant of the l. pneumophila corby strain and were able to identify the insertion site of the transposon. it is localised within an open reading frame which shows high homology to the alpha-subunit of the oxaloacetate decarboxylase (oada) of klebsiella pneumoniae. the oada homologous protein of l. pneumophila was detected in the wild-type strain by western b ... | 1996 | 8961567 |
| [legionnaires' disease is not uncommon in croatia]. | legionella pneumophila has been relatively frequent pathogen of pneumonias worldwide. it causes 2-15% of pneumonias requiring hospitalization. it appears sporadically and in outbreaks, and frequently as hospital-acquired infection. the main aim of this study is to show the permanent presence of legionnaires' disease in our country. in the 9-year period (1986-94), 42 patients were treated in the university hospital of infectious diseases "dr. fran mihaljevic" in zagreb. the disease was diagnosed ... | 1996 | 8965609 |
| severe community-acquired pneumonia: a possible role for chlamydia pneumoniae. | between july 1992 and june 1993, 61 patients with severe community-acquired pneumonia were admitted to our semi-intensive care unit. for all patients chest x-ray, blood gas analysis while breathing room air, gram stain and culture of bronchoaspirate, determination of acute and convalescent anti-body titers for legionella pneumophila, mycoplasma pneumoniae and chlamydia pneumoniae, blood culture when body temperature was greater than 38 degrees c, and pharyngeal swab for c. pneumoniae detection b ... | 1996 | 8966367 |
| distribution of mip-related sequences in 39 species (48 serogroups) of legionellaceae. | the macrophage infectivity potentiator gene (mip) from legionella pneumophila is a major virulence factor of the species. thus, mip-detection by amplification has been proposed to assess the presence of l. pneumophila in clinical and environmental samples. the distribution of mip-related sequences within the legionellaceae was studied by dna amplification using mip-specific primers followed by southern blot hybridization with an internal probe. thirty-nine species (48 serogroups) of legionellace ... | 1996 | 8972675 |
| the mouse region syntenic for human spinal muscular atrophy lies within the lgn1 critical interval and contains multiple copies of naip exon 5. | spinal muscular atrophy (sma) is a relatively common, autosomal recessively inherited neurodegenerative disorder that maps to human chromosome 5q13. this region of the human genome has an intricate genomic structure that has complicated the evaluation of sma candidate genes. we have chosen to study the mouse region syntenic for human sma in the hope that the homologous mouse interval would contain the same genes as human 5q13 on a simpler genomic background. here, we report the mapping of such a ... | 1996 | 8975718 |
| an iron- and fur-repressed legionella pneumophila gene that promotes intracellular infection and encodes a protein with similarity to the escherichia coli aerobactin synthetases. | legionella pneumophila, a parasite of alveolar macrophages, requires iron for intra- and extracellular growth. although its mechanisms for iron assimilation are poorly understood, this bacterium produces fur, a protein that can repress gene transcription in response to iron concentration. because iron- and fur-regulated genes are important for infection in other bacteria, the identification of similar genes in l. pneumophila was undertaken. a wild-type strain of l. pneumophila was randomly mutat ... | 1997 | 8975903 |
| bafilomycin a1 and intracellular multiplication of legionella pneumophila. | multiplication of legionella pneumophila in hela cells was found to be inhibited by noncytotoxic concentrations of bafilomycin a1, with blockage of bacterial growth at a concentration 15.6 nm. the inhibiting action was evident only when the antibiotic was present during the initial phase of intracellular multiplication, i.e., during the formation of the phagosome, whereas the addition of the drug did not affect microorganisms already actively multiplying within the phagosome. | 1997 | 8980784 |
| the alternative sigma factor sigma28 of legionella pneumophila restores flagellation and motility to an escherichia coli flia mutant. | gene expression in legionella pneumophila, the etiological agent of legionnaires' disease, can be controlled by alternative forms of rna polymerase programmed by distinct sigma factors. to understand the regulation of l. pneumophila flagellin expression, we cloned the sigma factor (flia) of rna polymerase responsible for the transcription of the flagellin gene, flaa. flia is a member of the sigma28 class of alternative sigma factors identified in several bacterial genera. the gene flia has been ... | 1997 | 8981975 |
| diagnosis of legionella pneumophila, mycoplasma pneumoniae, or chlamydia pneumoniae lower respiratory infection using the polymerase chain reaction on a single throat swab specimen. | diagnosis of mycoplasma pneumoniae and chlamydia pneumoniae lower respiratory infections using dna amplification by polymerase chain reaction (pcr) on throat swab specimens has been reported. in this study we determined the sensitivity of the detection of legionella pneumophila in simulated throat swab specimens by pcr. next, we compared the sensitivity and specificity of a single throat swab pcr with the current tests for diagnosis of legionella spp., m. pneumoniae, and c. pneumoniae in patient ... | 1996 | 8988757 |
| analysis of the intracellular fate of legionella pneumophila mutants. | l. pneumophila is a model organism for investigating the mechanisms by which intracellular pathogens acquire the metabolites needed for replication while evading the microbicidal mechanisms of the macrophage. we determined that intracellular l. pneumophila replicate in close association with the endoplasmic reticulum and suggest that l. pneumophila exploits the macrophage autophagy pathway to establish this specialized vacuole. to identify the bacterial factors required at this step as well as t ... | 1996 | 8993346 |
| use of salt to isolate legionella pneumophila mutants unable to replicate in macrophages. | | 1996 | 8993377 |
| 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 |
| legionella pneumophila pneumonia associated with acute respiratory distress syndrome successfully treated with imipenem. | although utility of beta-lactams in the treatment of legionnaire's disease could not be demonstrated, clinical cures of human legionellosis with imipenem have been reported. we report the case of a 45-year-old man who presented clinical and radiological features of 'typical' bacterial pneumonia. he was successfully treated with imipenem. serologic studies showed seroconversion for legionella pneumophila. | 1997 | 8996742 |
| [myocarditis in legionellosis. a case report]. | cardiac involvement during legionnaires' disease has been rarely described; few cases of myocarditis, pericarditis and endocarditis were reported. we describe a case of myocarditis associated to pneumonia, with high antibody title suggesting a disease due to legionella pneumophila. the patient had severe myocardial damage, with overt heart failure and important ecg and doppler-echocardiographic abnormalities, without associated multiorgan involvement. | 1996 | 8999366 |
| topology of legionella pneumophila dota: an inner membrane protein required for replication in macrophages. | the legionella pneumophila dota gene is required for intracellular growth of the bacterium in macrophages. in this study, a structure-function analysis of the dota protein was conducted to elucidate the role of this protein in l. pneumophila pathogenesis. translational fusions of dota to the escherichia coli phoa and lacz genes indicated that dota is an integral cytoplasmic membrane protein with eight membrane-spanning domains. dota contains two large periplasmic domains of approximately 503 and ... | 1997 | 9009315 |
| decreased intracellular survival of an fkpa mutant of salmonella typhimurium copenhagen. | the fkpa gene of salmonella typhimurium encodes a protein similar to the macrophage infectivity potentiator (mip) proteins of legionella pneumophila and chlamydia trachomatis. because mip proteins enhance the ability of these intracellular pathogens to survive within macrophages and epithelial cells, we tested whether the product of the fkpa gene would have the same effect on the intracellular growth of a virulent strain of s. typhimurium. by a series of p22 transductions, the fkpa gene of s. ty ... | 1997 | 9009347 |
| psychoactive cannabinoids increase mortality and alter acute phase cytokine responses in mice sublethally infected with legionella pneumophila. | marijuana contains both psychoactive and nonpsychoactive cannabinoids which have varying effects on the immune response system. previous studies with delta-9-tetrahydrocannabinol (thc), the major psychoactive component of marijuana, showed that this substance augmented the susceptibility of mice to infection with the opportunistic pathogen legionella pneumophila. the present study compared the enhancement of legionella-induced mortality in mice due to two other major of marijuana components, can ... | 1997 | 9012363 |
| prosthetic valve endocarditis due to legionella pneumophila. | prosthetic valve endocarditis is a potential complication of valve replacement surgery and warrants prompt diagnosis and appropriate treatment. thus, the blood culture in addition to providing an etiological organism is important in establishing appropriate antibiotic therapy. a case of prosthetic valve endocarditis (pve) is presented with repeatedly negative blood cultures at a community hospital and refractory to prolonged therapy with standard antibiotic regimens. appropriate workup eventuall ... | 1996 | 9016982 |
| marked inhibition of the intracellular multiplication of legionella pneumophila in monocytes isolated from carriers of human t lymphotrophic virus type i. | intracellular growth patterns of legionella pneumophila were examined in monocytes obtained from carriers of human t-lymphotropic virus type i (htlv-1) and controls who were htlv-1 seronegative. all subjects were seronegative for antibodies against l. pneumophila. bacterial growth was determined 0, 1, 2, and/or 3 days after infecting peripheral blood mononuclear cells (pbmcs) with the bacteria. the intracellular growth of l. pneumophila was markedly inhibited in htlv-1 carriers compared with nor ... | 1997 | 9021917 |
| a cytosolic serine endopeptidase from trypanosoma cruzi is required for the generation of ca2+ signaling in mammalian cells. | an early event in the trypanosoma cruzi cell invasion process, the recruitment of host lysosomes, led us to investigate the involvement of signal transduction. infective trypomastigotes were found to contain a soluble ca2+-signaling activity for mammalian cells that is sensitive to protease inhibitors. inhibitor and substrate utilization profiles were used to purify a candidate peptidase for involvement in this process, from which we isolated a full-length cdna clone. the sequence revealed a nov ... | 1997 | 9024691 |
| natural resistance to infection with intracellular pathogens: the nramp1 protein is recruited to the membrane of the phagosome. | the nramp1 (natural-resistance-associated macrophage protein 1) locus (bcg, ity, lsh) controls the innate resistance or susceptibility of mice to infection with a group of unrelated intracellular parasites which includes salmonella, leishmania, and mycobacterium. nramp1 is expressed exclusively in professional phagocytes and encodes an integral membrane protein that shares structural characteristics with ion channels and transporters. its function and mechanism of action remain unknown. the intr ... | 1997 | 9034150 |
| [serologic diagnosis of severe non-bacterial pneumonia and acquired in the community]. | the aim of this study was to evaluate the profitability of the serology, especially against streptococcus pneumoniae and chlamydia sp., in the community pneumonia with hospital admission. | 1996 | 9035712 |
| impact of management guidelines on the outcome of severe community acquired pneumonia. | ten years ago we published a study of 50 adults with severe community acquired pneumonia admitted to our intensive care unit and subsequently introduced guidelines for the management of severe community acquired pneumonia which are largely in accordance with those of the british thoracic society. the results of a follow up study are now reported in order to assess their impact on the outcome of this disease. | 1997 | 9039234 |
| flow cytometric determination of endocytosis of viable labelled legionella pneumophila by acanthamoeba palestinensis. | endocytosis of fluorescently labelled cells of legionella pneumophila (l. pneumophila) by free-living acanthamoeba palestinensis (a. palestinensis) has been studied using flow cytometry. l. pneumophila cells were labelled with cm-dii, a lipophilic fluorescent probe under conditions that did not modify viability. coculturing the bacteria with amoebae was accompanied by rapid endocytosis; after 5 min, 90% of the amoebae had internalized bacteria. this percentage remained unchanged during further c ... | 1997 | 9041116 |
| a study of iron acquisition mechanisms of legionella pneumophila grown in chemostat culture. | we recently demonstrated that the virulence of a clinical isolate of legionella pneumophila is significantly attenuated when cultured in an iron-limited environment. in this study the influence of iron limitation on the expression of enzyme activities and iron-transport mechanisms was investigated. expression of the important pathogenicity factor, the zinc metalloprotease, was reduced fivefold in response to iron limitation. ferric citrate reductase activity was demonstrated in both iron-limited ... | 1997 | 9058545 |
| differential effects of granulocyte/macrophage colony-stimulating factor (gm-csf) in enhancing macrophage resistance to legionella pneumophila vs candida albicans. | it has been reported that granulocyte/macrophage colony-stimulating factor (gm-csf), one of the hemopoietic growth factors which regulates the function of phagocytic cells, is a potent activator of cultured macrophages and induces antimicrobial activities as well as differentiation of precursor cells. in this study, we examined the ability of recombinant murine gm-csf to activate mouse peritoneal macrophages to restrict the growth of two different microorganisms, candida albicans and legionella ... | 1997 | 9070320 |
| legionnaires' disease: co-infection with legionella pneumophila serogroups 1 and 5. | | 1997 | 9076276 |
| legionnaire's disease during pregnancy: a case presentation and review of the literature. | acute pneumonia complicating pregnancy can have serious consequences for both the mother and the fetus. streptococcus pneumoniae remains the most common bacterial pathogen, but legionella pneumophila must be considered as well, especially in severe multisystem disease. with severe disease, premature delivery may occur as has been described in the only previous report of legionnaire's disease during pregnancy. we present here the first report of legionnaire's disease in pregnancy, resulting in th ... | 1997 | 9076416 |
| [determination of cutoff value of serum anti-legionella antibody titer--microplate agglutination test (mpat)]. | in order to promote the serological diagnosis of legionellosis in the clinical laboratory, the cutoff values of serum anti-legionella antibody titers for microplate agglutination (mpat) test were determined. antibody levels were tested for 178 serum specimens including 98 healthy persons, 22 ordinally workers having either metabolic or renal failure, definitely diagnosed patients of 17 mycoplasmal and 9 chlamydial pneumonia, 32 patients of other bacterial pneumonia. heat killed unstained cell su ... | 1997 | 9077068 |
| [a case of fatal pneumonia caused by legionella pneumophila serogroup 6 developed after drowning in a public bath]. | a 57-year-old male was admitted to our hospital because of high fever, productive cough and dyspnea. six days prior to admission he had an episode of drowning in a public bath. on admission chest x-ray showed wide-spread pneumonia causing severe respiratory distress for which mechanical ventilatory support was started. despite chemotherapy including erythromycin and rifampicin his condition continued to deteriorate. chemistry showed marked elevation of cpk and findings of acute renal failure. he ... | 1997 | 9077075 |
| excellent activity of newer quinolones on legionella pneumophila in j774 macrophages. | the activity of six antibiotics directed against intracellularly multiplying legionella pneumophilia was examined in tissue cultures with j774 macrophages. the drugs tested were the new quinolones, bay y 3118 and clinafloxacin, and ciprofloxacin, erythromycin, gentamicin and ampicillin served as reference drugs. additionally, the mics of these drugs against l. pneumophila were determined in vitro by broth microdilution. despite their low mic values, ampicillin and gentamicin did not inhibit intr ... | 1997 | 9084116 |
| cloning and nucleotide sequences of iron and copper-zinc superoxide dismutase genes of legionella pneumophila and their distribution among legionella species. | a facultative intracellular parasite legionella pneumophila has two kinds of superoxide dismutase (sod), iron-containing superoxide dismutase (fe-sod) and copper,zinc-containing one (cu,zn-sod). we cloned both sod genes of l. pneumophila and determined their dna sequences. the fe-sod gene (sodb), isolated by functional complementation of a sod-deficient escherichia coli strain, encoded a protein of 192 amino acids conserving the fe-sod-specific amino acid residues. a clone containing entire cu,z ... | 1996 | 9086394 |
| characterization and cloning of a 37.6-kb plasmid carried by legionella pneumophila recovered from patients and hospital water over a 12-year period. | for 12 years, strains of legionella pneumophila serogroup 1 harbouring a 37.6-kb (23 mda) plasmid have predominated among patient and potable water isolates at the victoria general hospital, halifax, n.s. plasmid dna recovered from 24 strains isolated between 1983 and 1995 was digested with the restriction endonucleases ecori, hindiii, kpni, pvuii, xbai, and bamhi. the distribution of cutting sites indicated that the 23-mda size group had remained essentially unchanged during this period, sugges ... | 1997 | 9090107 |
| [community acquired pneumonia. reliability of the criteria for deciding ambulatory treatment]. | to determine whether criteria for not admitting community-acquired pneumonia (cap) patients diagnosed in the emergency room are appropriate, and to characterize the symptoms, etiology and course of cap. this one-year prospective, protocol study of immunocompetent cap patients diagnosed in the emergency room of our hospital enrolled patients not considered to require hospital admission according to the recommendations of the spanish society of respiratory disease (separ). medical histories, chest ... | 1997 | 9091117 |
| multiplication of different legionella species in mono mac 6 cells and in acanthamoeba castellanii. | survival and distribution of legionellae in the environment are assumed to be associated with their multiplication in amoebae, whereas the ability to multiply in macrophages is usually regarded to correspond to pathogenicity. since most investigations focused on legionella pneumophila serogroup 1, we examined the intracellular multiplication of different legionella species in mono mac 6 cells, which express phenotypic and functional features of mature monocytes, and in acanthamoeba castellanii, ... | 1997 | 9097418 |
| high-resolution linkage map of mouse chromosome 13 in the vicinity of the host resistance locus lgn1. | natural resistance of inbred mouse strains to infection with legionella pneumophila is controlled by the expression of a single dominant gene on chromosome 13, designated lgn1. the genetic difference at lgn1 is phenotypically expressed as the presence or absence of intracellular replication of l. pneumophila in host macrophages. in our effort to identify the lgn1 gene by positional cloning, we have generated a high-resolution linkage map of the lgn1 chromosomal region. for this, we have carried ... | 1997 | 9119362 |
| porcine interferon-gamma inhibits the growth of legionella pneumophila in wiref cells in vitro. | the intracellular growth of legionella pneumophila in wiref (wistar rat embryonal fibroblast) cells was inhibited by porcine interferon-gamma. the effect was compared with that of different human interferons (alpha and gamma). the growth inhibition was dose-dependent and required the pretreatment of wiref cells with interferon. the development of an antibacterial state of the cells was observed. when interferon was added together with bacteria or 1 d after the infection there was no inhibition. ... | 1996 | 9131787 |
| resuscitation of viable but nonculturable legionella pneumophila philadelphia jr32 by acanthamoeba castellanii. | legionella pneumophila is an aquatic bacterium and is responsible for legionnaires' disease in humans. free-living amoebae are parasitized by legionellae and provide the intracellular environment required for the replication of this bacterium. in low-nutrient environments, however, l. pneumophila is able to enter a non-replicative viable but nonculturable (vbnc) state. in this study, l. pneumophila philadelphia i jr 32 was suspended in sterilized tap water at 10(4) cells/ml. the decreasing numbe ... | 1997 | 9143134 |
| [rhabdomyolysis associated with legionella pneumophila pneumonia]. | | 1997 | 9147510 |
| rapid diagnosis of legionella pneumophila serogroup 1 infection with the binax enzyme immunoassay urinary antigen test. | the binax legionella urinary antigen (lua) enzyme immunoassay (binax, portland, maine) was evaluated in 159 patients with suspected or proven legionellosis and 209 controls. a positive lua test was found in 37% of patients with suspected legionellosis overall and in 83% of those with proven legionella pneumophila serogroup 1 infection. the sensitivity of the lua test was significantly greater than that of the direct fluorescent-antigen test (83 versus 42%; p < 0.0001) but not significantly diffe ... | 1997 | 9157160 |
| direct detection and identification of pseudomonas aeruginosa in clinical samples such as skin biopsy specimens and expectorations by multiplex pcr based on two outer membrane lipoprotein genes, opri and oprl. | a multiplex pcr test based on the simultaneous amplification of two lipoprotein genes, opri and oprl, was designed and evaluated for its ability to directly detect fluorescent pseudomonads (amplification of opri open reading frame, 249 bp) and pseudomonas aeruginosa (amplification of oprl open reading frame, 504 bp) in clinical material. a collection of reference strains including 20 different species of fluorescent pseudomonads was tested. positive pcr results for both genes were observed only ... | 1997 | 9163432 |
| use of heteroduplex analysis to classify legionellae on the basis of 5s rrna gene sequences. | seventeen different species of legionella, 12 serogroups of legionella pneumophila, and 2 legionella-like amoebal pathogens (llap1 and sarcobium lyticum) were examined by heteroduplex analysis of pcr products of the 5s rrna gene. eight different banding patterns were identified, indicating that heteroduplex analysis of this gene can be used to classify these bacteria according to base substitutions between species. this classification may have future applications in clinical and epidemiological ... | 1997 | 9163496 |
| comparison of radioimmunoassay and enzyme immunoassay kits for detection of legionella pneumophila serogroup 1 antigen in both concentrated and nonconcentrated urine samples. | we evaluated a commercial enzyme immunoassay (eia) kit for detection of legionella pneumophila serogroup 1 soluble antigen by comparing it to radioimmunoassay (ria), using both concentrated and nonconcentrated urine samples. the sensitivity of eia was 67.4% in nonconcentrated urine samples and 82.6% in concentrated urine samples. the sensitivity of ria was 60.9% and 84.8% in nonconcentrated and concentrated urine samples, respectively. our study indicates that the sensitivity and specificity of ... | 1997 | 9163502 |
| analysis of the legionella pneumophila flii gene: intracellular growth of a defined mutant defective for flagellum biosynthesis. | using a pcr-based strategy and degenerate oligonucleotides, we isolated a legionella pneumophila gene that showed high sequence similarity to members of the flii gene family. an insertion mutation that disrupted the flii open reading frame was recombined onto the l. pneumophila chromosome and analyzed for its effects on production of flagella and intracellular growth. the mutation resulted in loss of surface-localized flagellin protein but had no effect on the ability of the bacteria to grow wit ... | 1997 | 9169800 |
| cloning and characterization of two immunophilin-like genes, ilpa and fkpa, on a single 3.9-kilobase fragment of aeromonas hydrophila genomic dna. | antiserum to aeromonas hydrophila a6 cell envelopes was shown in a previous study (c. y. f. wong, g. mayrhofer, m. w. heuzenroeder, h. m. atkinson, d. m. quinn, and r. l. p. flower, fems immunol. med. microbiol. 15:233-241, 1996) to protect mice against lethal infection by this organism. in this study, colony blot analysis of an a. hydrophila genomic library using antiserum to a. hydrophila a6 cell envelopes revealed a cosmid clone expressing a 30-kda protein which has not been described previou ... | 1997 | 9171380 |
| isolation of a gene encoding a novel spectinomycin phosphotransferase from legionella pneumophila. | a gene capable of conferring spectinomycin resistance was isolated from legionella pneumophila, the agent of legionnaires' disease. the gene (aph) encoded a 36-kda protein which has similarity to aminoglycoside phosphotransferases. biochemical analysis confirmed that aph encodes a phosphotransferase which modifies spectinomycin but not hygromycin, kanamycin, or streptomycin. the strain that was the source of aph demonstrated resistance to spectinomycin, and southern hybridizations determined tha ... | 1997 | 9174205 |
| transcriptional regulation of the macrophage-induced gene (gspa) of legionella pneumophila and phenotypic characterization of a null mutant. | expression of the global stress protein gene (gspa) is induced during the intracellular infection of macrophages and upon exposure of legionella pneumophila to in vitro stress stimuli. transcription of gspa is regulated by two promoters, one of which is regulated by the sigma 32 heat-shock transcription factor. we utilized a gspa promoter fusion to a promoter less lacz to probe the phagososmal 'microenvironment' for the kinetics of exposure of intracellular l. pneumophila to stress stimuli. expr ... | 1997 | 9179855 |
| the role of arbitrarily primed pcr in identifying the source of an outbreak of legionnaires' disease. | an outbreak of community-acquired legionnaires' disease (ld) occurred in providence, r.i., in fall 1993. to find the outbreak source, exposures of 17 case patients were compared to those of 33 matched controls. case patients were more likely than controls to have visited a section of downtown (area a) during the 2 weeks before illness (11 [65%] versus 9 [27%]; matched odds ratio, 6.5; p = 0.01). water samples were cultured from 27 aerosol-producing devices within area a. legionella pneumophila s ... | 1997 | 9196197 |
| stability of legionella urinary antigens over time. | twenty-two urine samples positive for legionella pneumophila serogroup 1 antigen by equate radioimmunoassay (ria) (binax, portland, me, usa) were stored at various temperatures and the ria repeated at 1, 7, 30, 90, and 120 days to evaluate stability of the urinary antigens. the mean ratios of patient/negative control remained stable. although there was a 10% decrease in the mean ratios after 1 month, changes were not significant. however, individual samples with ratios close to 3 may fall to < 3 ... | 1997 | 9218912 |
| lack of resistance to erythromycin, rifampicin and ciprofloxacin in 98 clinical isolates of legionella pneumophila. | ninety-eight consecutive clinical isolates of legionella pneumophila were tested for erythromycin, rifampicin and ciprofloxacin susceptibility. mics, determined by agar dilution testing, were in the range 0.06-1 mg/l of erythromycin, 0.007-0.015 mg/l of rifampicin and 0.015-0.03 mg/l of ciprofloxacin. no resistance against the antibiotics tested was detected. it is thus likely that therapeutic failures in legionnaires' disease are not related to the emergence of resistance against commonly used ... | 1997 | 9222053 |
| [legionella pneumonia successfully treated despite late diagnosis]. | status asthmaticus developed in a 72-year-old man who was being treated with oral prednisolone for severe persistent asthma. the dosage of prednisolone was increased, and amikacin was injected to treat pneumonia that had developed in the right lung. progressive pulmonary infiltrates, respiratory compromise, and hypoxemia developed, and the patient eventually required mechanical ventilation. antibiotic treatment was changed to imipenem/cilastatin, piperacillin, gentamicin, clarithromycin, erythro ... | 1997 | 9234637 |
| [legionella infection with rhabdomyolysis]. | rhabdomyolysis complicating infection with legionella pneumophila has previously been reported and may in some cases have led to acute tubular interstitial necrosis. we report a case of severe legionnaires' disease complicated with rhabdomyolysis, myoglobinuria and neurological symptoms. treatment with erythromycin and rifampicin was initiated early in the course of disease. the myoglobinuria was treated with forced diuresis and alkanization and renal failure did not develop. the frequency of rh ... | 1997 | 9245043 |
| flagella are a positive predictor for virulence in legionella. | pathogenesis of legionnaires>> disease is strictly related to the ability of the legionellae to infect phagocytic cells, yet surface markers of virulence in legionella isolates are currently unknown. rabbit antibodies raised against purified flagella of legionella pneumophila serogroup 1 recognized a total of 24 of 30 laboratory-maintained isolates of l. pneumophila serogroups 1-15 and 16 of 24 other legionella species tested by rapid immunoblot and indirect immunofluorescence assay. all isolate ... | 1997 | 9245622 |
| identification of a gal/galnac lectin in the protozoan hartmannella vermiformis as a potential receptor for attachment and invasion by the legionnaires' disease bacterium. | the legionnaire's disease bacterium, legionella pneumophila, is a facultative intracellular pathogen which invades and replicates within two evolutionarily distant hosts, free-living protozoa and mammalian cells. invasion and intracellular replication within protozoa are thought to be major factors in the transmission of legionnaire's disease. although attachment and invasion of human macrophages by l. pneumophila is mediated in part by the complement receptors cr1 and cr3, the protozoan recepto ... | 1997 | 9254652 |
| adenosine deaminase activity in the aetiological diagnosis of community-acquired pneumonia. | a prospective study was undertaken to assess the usefulness of serum adenosine deaminase (ada) activity in the aetiological diagnosis of 75 patients (mean age 58 years) with community-acquired pneumonia who required hospitalization. measurements of ada were also carried out in 35 healthy subjects (mean age 52 years). the serum ada activity in patients with typical bacterial pneumonia (tbp) was 21 +/- 7 iu/l and in controls 22 +/- 9 iu/l. in 43 patients with atypical pneumonia (ap), ada levels (4 ... | 1997 | 9255891 |
| [infection with legionella pneumophila among workers of polish sea drilling platforms]. | the epidemiology, clinic, diagnostic dates and treatment of legionella pneumophila (l. pneumophila) were discussion. the our study were removal in 246 workers seas drill platforms. the antibody opposed of l. pneumophila were mean in 54 with 246 workers. investigation were execution into conjunction of specifically job and life workers and frequently appearance of bronchitis. the antibody l. pneumophila were detection in 25% persons. these dates may suggest possibilities of l. pneumophila infecti ... | 1997 | 9297350 |
| risk assessment of opportunistic bacterial pathogens in drinking water. | this study was undertaken to examine quantitatively the risks to human health posed by heterotrophic plate count (hpc) bacteria found naturally in ambient and potable waters. there is no clear-cut evidence that the hpc bacteria as a whole pose a public health risk. only certain members are opportunistic pathogens. using the four-tiered approach for risk assessment from the national academy of sciences, hazard identification, dose-response modeling, and exposure through ingestion of drinking wate ... | 1997 | 9297985 |
| a multicenter, randomized study comparing the efficacy and safety of intravenous and/or oral levofloxacin versus ceftriaxone and/or cefuroxime axetil in treatment of adults with community-acquired pneumonia. | five hundred ninety patients were enrolled in a prospective, multicenter, randomized trial comparing the efficacy and safety of 7 to 14 days of levofloxacin treatment with that of ceftriaxone and/or cefuroxime axetil in the management of community-acquired pneumonia in adults. patients received either intravenous and/or oral levofloxacin (500 mg once daily) or the comparative agents, parenteral ceftriaxone (1 to 2 g once to twice daily) and/or oral cefuroxime axetil (500 mg twice daily). erythro ... | 1997 | 9303395 |
| nosocomial legionellosis traced to a contaminated ice machine. | to investigate a case of nosocomial legionellosis, identify pathways of transmission, and effect control of the environmental source. | 1997 | 9309436 |
| [isolation of legionella pneumophila from 24 hr-home bath water and an eradication trial of the bacteria from the bath]. | contamination of 24 hr home bath with legionella pneumophila is recently well recognized. eradication of the water-bath contamination from l. pneumophila and other bacteria is an important matter to prevent the infection because the 24 hr-bathing facility is widely accepted in japanese houses. among the 16 bathing water samples we tested, legionella pneumophia was isolated from 6 cases (37.5%) when the bathing water was not treated with disinfectants. number of l. pneumophila increased up to 10( ... | 1997 | 9311194 |
| colonization of transplant unit water supplies with legionella and protozoa: precautions required to reduce the risk of legionellosis. | organ transplant recipients and other immunosuppressed patients are known to be at increased risk of nosocomial legionnaires' disease. although the ecology of legionella in hospital water storage and distribution systems (including a protozoonotic relationship with free-living protozoa) has been well documented, little is known regarding the quality of water supplied to high-risk units. hot- and cold-water samples (two first draw and one run to waste for 5 min) were taken from 69 (85%) of the 81 ... | 1997 | 9321724 |
| pseudoepidemic of legionella pneumophila serogroup 6 associated with contaminated bronchoscopes. | an investigation of a pseudoepidemic of legionella pneumophila serogroup 6 contaminating bronchoalveolar lavage specimens traced the source to contaminated tap water used to rinse disinfected bronchoscopes. the problem recurred despite plumbing changes and the installation of filters in the endoscopy unit water system because of inadequate maintenance of the filters. | 1997 | 9321725 |
| susceptibility of ninety-eight clinical isolates of legionella to macrolides and quinolones using the etest. | isolates of legionella from 98 patients with legionnaires' disease hospitalized in columbus, ohio, usa between 1991 through 1995 were tested for antimicrobial susceptibility to macrolides and quinolones using the etest. most (87%) isolates were legionella pneumophila serogroup 1. all isolates tested remain susceptible to erythromycin, azithromycin, clarithromycin, ciprofloxacin, ofloxacin, and levofloxacin. in vitro susceptibility testing of legionella to representative macrolides and quinolones ... | 1997 | 9327252 |
| cloning and sequence analysis of a novel hemolysin gene (vlly) from vibrio vulnificus. | a gene (vlly) encoding a novel hemolysin of vibrio vulnificus ckm-1 has been cloned and sequenced. when the vlly gene was expressed in minicells, a unique peptide of approximately 40 kda was identified. subcellular fractionation of escherichia coli cells carrying the vlly gene indicated that the vlly protein was distributed in both the cytoplasmic and the periplasmic fractions, with the notable ability to appear in the latter compartment. nucleotide sequence analysis predicted a single open read ... | 1997 | 9327548 |
| cloning and sequencing of the dnak and grpe genes of legionella pneumophila. | a 4.4-kb dna fragment from legionella pneumophila (lp) was isolated, which could complement an escherichia coli (ec) dnak ts mutant, hc4102. nucleotide sequence analysis of the region revealed two complete open reading frames (orfs) encoding both a predicted dnak protein of 644 aa and a predicted grpe protein of 199 aa, and also the 5'-end of the predicted dnaj gene organized in the order of grpe-dnak-dnaj. consensus heat shock (hs) promoter sequences were identified upstream of the start of bot ... | 1997 | 9332363 |
| antibody-mediated depletion of tumor necrosis factor-alpha impairs pulmonary host defenses to legionella pneumophila. | tumor necrosis factor-alpha (tnf-alpha) has been shown to stimulate the resistance of alveolar macrophages and neutrophils to legionella pneumophila in vitro. to determine whether endogenous tnf-alpha is necessary for host defense against legionellosis in vivo, anti-tnf-alpha igg or control igg was administered to rats exposed to aerosolized l. pneumophila. treatment with anti-tnf-alpha neutralized >90% of the intrapulmonary tnf-alpha response to infection, resulting in persistent pneumonitis an ... | 1997 | 9333161 |
| in-vitro activities of ciprofloxacin, levofloxacin, lomefloxacin, ofloxacin, pefloxacin, sparfloxacin and trovafloxacin against gram-positive and gram-negative pathogens from respiratory tract infections. | trovafloxacin, sparfloxacin, ciprofloxacin and levofloxacin were equally active against moraxella catarrhalis, haemophilus influenzae, legionella pneumophila, klebsiella pneumoniae, enterobacter cloacae and serratia marcescens. ciprofloxacin was the most active compound against pseudomonas aeruginosa (mic90 = 1 mg/l), followed by trovafloxacin (mic90 = 4 mg/l). trovafloxacin was twice as active as sparfloxacin against streptococcus pyogenes (mic90 = 0.12 mg/l), streptococcus pneumoniae (mic90 = ... | 1997 | 9338498 |
| safe haven: the cell biology of nonfusogenic pathogen vacuoles. | our understanding of both membrane traffic in mammalian cells and the cell biology of infection with intracellular pathogens has increased dramatically in recent years. in this review, we discuss the cell biology of the host-microbe interaction for four intracellular pathogens: chlamydia spp., legionella pneumophila, mycobacterium spp., and the protozoan parasite toxoplasma gondii. all of these organisms reside in vacuoles inside cells that have restricted fusion with host organelles of the endo ... | 1997 | 9343356 |
| antigenic lipopolysaccharide components of legionella pneumophila recognized by monoclonal antibodies: possibilities and limitations for division of the species into serogroups. | legionella pneumophila accounts for the majority of cases of legionnaires' disease. by using rabbit antisera, the species has been divided into 14 numbered and 1 unnumbered serogroups. to recognize the antigenic diversity of the lipopolysaccharide (lps) responsible for this classification, the dresden legionella lps mab panel, containing 98 monoclonal antibodies (mabs), was created. each serogroup reference strain possesses at least one specific epitope not found on any other reference strain an ... | 1997 | 9350744 |
| utilization of similar mechanisms by legionella pneumophila to parasitize two evolutionarily distant host cells, mammalian macrophages and protozoa. | the legionnaires' disease bacterium, legionella pneumophila, is an intracellular pathogen of humans that is amplified in the environment by intracellular multiplication within protozoa. within both evolutionarily distant hosts, the bacterium multiplies in a rough endoplasmic reticulum-surrounded phagosome that is retarded from maturation through the endosomal-lysosomal degradation pathway. to gain an understanding of the mechanisms utilized by l. pneumophila to invade and replicate within two ev ... | 1997 | 9353059 |
| intrapulmonary hartmannella vermiformis: a potential niche for legionella pneumophila replication in a murine model of legionellosis. | the potential role of inhaled protozoa as a niche for intrapulmonary replication of legionella pneumophila was investigated in vivo with mutant strains of l. pneumophila which have reduced virulence for the amoeba hartmannella vermiformis. l. pneumophila aa488 and aa502 were derived from wild-type strain aa100 after transposon mutagenesis. these mutants have reduced virulence for h. vermiformis but are fully virulent for mononuclear phagocytic cells. a/j mice, which are susceptible to replicativ ... | 1997 | 9353084 |
| use of the polymerase chain reaction for the detection of legionella pneumophila dna in serum samples. | | 1997 | 9356824 |
| prognostic factors of severe legionella pneumonia requiring admission to icu. | despite the fact that the epidemiology of community-acquired pneumonia and nosocomial legionella infection is well known, there are no specific reports dealing with severe cases of legionella pneumophila pneumonia admitted to intensive care units. we undertook a prospective study upon 84 patients with a reliable diagnosis of l. pneumophila pneumonia that required icu admission. the study assessed the prognostic factors, clinical, radiological and outcome variables of both nosocomial (n = 33) and ... | 1997 | 9372662 |
| efficacy and safety of grepafloxacin 600 mg daily for 10 days in patients with community-acquired pneumonia. | the efficacy and safety of grepafloxacin in treating patients with community-acquired pneumonia (cap) was assessed in an open-label, noncomparative study. patients (n = 273) received grepafloxacin 600 mg qd for 10 days. a total of 237 patients (87%) completed the study. in assessable patients, the clinical success rate at follow-up (4 to 6 weeks after the last dose) was 89% (211/238 patients). in microbiologically assessable patients, the eradication rate at follow-up was 95% (86/91 isolates). g ... | 1997 | 9385485 |
| intracellular multiplication of legionella pneumophila: human pathogen or accidental tourist? | | 1998 | 9386330 |
| characterization of a new region required for macrophage killing by legionella pneumophila. | in a previous study, a collection of 55 legionella pneumophila mutants defective for macrophage killing was isolated by transposon mutagenesis. in this study, nine of these mutants that belong to the same dna hybridization group (group 3) were characterized. a wild-type dna fragment that covers this dna hybridization group was cloned and sequenced. this region was found to contain six new genes (designated icmt, icms, icmr, icmq, icmp, and icmo), five of which contain at least one transposon ins ... | 1997 | 9393796 |
| the role of legionella pneumophila-infected hartmannella vermiformis as an infectious particle in a murine model of legionnaire's disease. | legionella pneumophila is a bacterial parasite of many species of freshwater protozoa and occasionally an intracellular pathogen of humans. while protozoa are known to play a key role in the persistence of l. pneumophila in the environment, there has been limited research addressing the potential role of l. pneumophila-infected protozoa in the pathogenesis of human infection. in this report, the potential role of an l. pneumophila-infected amoeba as an infectious particle in replicative l. pneum ... | 1997 | 9393834 |
| identification of legionella species by lipopolysaccharide antigen pattern. | electrophoretic analysis of lipopolysaccharide (lps) extracts from 430 previously serotyped legionella isolates and 28 american type culture collection (atcc) non-legionella pneumophila legionella reference strains representing different legionella species and serogroups has been performed. lps was prepared from legionella suspensions by sonication and proteinase k digestion. following sodium dodecyl sulfate-polyacrylamide gel electrophoresis, lps bands were either stained with silver nitrate or ... | 1997 | 9399493 |
| chemical characterization of a new 5,7-diamino-3,5,7,9-tetradeoxynonulosonic acid released by mild acid hydrolysis of the legionella pneumophila serogroup 1 lipopolysaccharide. | a derivative of a new 5,7-diamino-3,5,7,9-tetradeoxynonulosonic acid was released from the lipopolysaccharide of legionella pneumophila serogroup 1 (strain philadelphia 1) by mild acid hydrolysis, and identified, using nmr spectroscopy and glc-ms, as 5,7-diacetamido-8-o-acetyl-3,5,7,9-tetradeoxy-l-glycero-d-talo- nonulosonic acid or its enantiomer. | 1997 | 9403997 |
| identification of an alpha-d-manp-(1-->8)-kdo disaccharide in the inner core region and the structure of the complete core region of the legionella pneumophila serogroup 1 lipopolysaccharide. | a disaccharide alpha-d-mannopyranosyl-(1-->8)-3-deoxy-d-manno-octulosonic acid [alpha-d-manp-(1-->8)-kdo] was released by mild acid degradation of legionella pneumophila serogroup 1 (strain philadelphia 1) lipopolysaccharide (lps) and identified using nmr spectroscopy and glc-ms of derived products. these data, together with methylation analysis of the native lps and previously reported data [y.a. knirel, h. moll, and u. zähringer, carbohydr. res., 293 (1996) 223-234], allowed elucidation of the ... | 1997 | 9403999 |
| detection of legionella pneumophila in wastewater by nested polymerase chain reaction. | the study of legionella in treated wastewater acquires special importance when this water is used in irrigation by spray, as legionella is transmitted via the inhalation of aerosols and may consequently represent a health risk. in this study, we applied polymerase chain reaction (pcr) amplification as an alternative method to plate culture for detecting l. pneumophila in twelve heavily biocontaminated samples from a wastewater treatment plant. moreover, we studied the efficiency of rapid gel fil ... | 1997 | 9404507 |
| [effect of silver and copper ions on survival of legionella pneumophila in tap water]. | in vitro studies were performed to give information about the required metal concentrations in decontaminating legionella-loaded warm water systems with the electrochemical generation of ag+ and cu2+ ions. the influence of ag and cu ions, as single compounds and in combination, on the survival of legionella pneumophila (serogroup 6) was determined in tap water at 45 degrees c. marked differences were detected in the action of these metals. ag produced a much stronger inhibition than cu. no addit ... | 1996 | 9409904 |
| [isolation and biological characterization of legionella pneumophila mutants resistant to aminoglycoside antibotics and their protective action]. | preliminary estimation of virulence in some antibiotic resistant mutants of legionella pneumophila, philadelphia 1 in various models of infection revealed its decrease in the mutants resistant to azlocillin, cefotaxime, fluoroquinolone lib-80, neamine and streptomycin. detailed investigation of the neamine resistant mutants showed that in relation to streptomycin susceptibility such mutants could be divided into 3 classes: susceptible to streptomycin, resistant to high concentrations of streptom ... | 1997 | 9412401 |
| [community-acquired pneumonia: etiological diagnosis]. | microbiological and immunoserological approaches were used in etiological diagnosis of community-acquired pneumonia. it was concluded that streptococcus pneumoniae, staphylococcus aureus, pseudomonas aeruginosa, legionella pneumophila and klebsiella pneumoniae predominated in the etiological structure of present severe community-acquired pneumonia. the most actual causative agents of nonsevere community-acquired pneumonia in persons under 60 were s. pneumoniae, hemophilus influenzae, mycoplasma ... | 1997 | 9412402 |
| potato leafroll virus binds to the equatorial domain of the aphid endosymbiotic groel homolog. | a groel homolog with a molecular mass of 60 kda, produced by the primary endosymbiotic bacterium (a buchnera sp.) of myzus persicae and released into the hemolymph, has previously been shown to be a key protein in the transmission of potato leafroll virus (plrv). like other luteoviruses and pea enation mosaic virus, plrv readily binds to extracellular buchnera groel, and in vivo interference in this interaction coincides with reduced capsid integrity and loss of infectivity. to gain more knowled ... | 1998 | 9420234 |
| effect of levofloxacin, erythromycin or rifampicin pretreatment on growth of legionella pneumophila in human monocytes. | opsonophagocytic killing of some bacteria (staphylococcus aureus, pseudomonas aeruginosa) by phagocytes is enhanced by previous brief exposure of the organism to antibiotics. we studied the regrowth of legionella pneumophila previously pretreated with levofloxacin, erythromycin and/or rifampicin in human monocytes. the mic for the l. pneumophila isolate of levofloxacin, erythromycin and rifampicin was 0.03, 0.5 and 0.001 mg/l, respectively. growth of l. pneumophila from buffered charcoal yeast e ... | 1997 | 9421315 |
| in vivo regulation of replicative legionella pneumophila lung infection by endogenous interleukin-12. | the in vivo role of endogenous interleukin 12 (il-12) in modulating intrapulmonary growth of legionella pneumophila was assessed by using a murine model of replicative l. pneumophila lung infection. intratracheal inoculation of a/j mice with virulent bacteria (10(6) l. pneumophila cells per mouse) resulted in induction of il-12, which preceded clearance of the bacteria from the lung. inhibition of endogenous il-12 activity, via administration of il-12 neutralizing antiserum, resulted in enhanced ... | 1998 | 9423840 |
| induced expression of the legionella pneumophila gene encoding a 20-kilodalton protein during intracellular infection. | the eukaryotic protein synthesis inhibitor cycloheximid has been used by many investigators to selectively radiolabel intracellular bacteria. although cycloheximide has no direct effect on bacterial gene expression, there are concerns that long-term inhibition of the host cell protein synthesis may have secondary effects on bacterial gene expression. therefore, prior to further identification and cloning of the macrophage-induced (mi) genes of legionella pneumophila, the effects of cycloheximide ... | 1998 | 9423859 |
| periplasmic superoxide dismutase in meningococcal pathogenicity. | meningococcal sodc encodes periplasmic copper- and zinc-cofactored superoxide dismutase (cu,zn sod) which catalyzes the conversion of the superoxide radical anion to hydrogen peroxide, preventing a sequence of reactions leading to production of toxic hydroxyl free radicals. from its periplasmic location, cu,zn sod was inferred to acquire its substrate from outside the bacterial cell and was speculated to play a role in preserving meningococci from the action of microbicidal oxygen free radicals ... | 1998 | 9423860 |
| clinical evaluation of a new pcr assay for detection of coxiella burnetii in human serum samples. | a nested pcr method was developed for the detection of coxiella burnetii in human serum samples. two pairs of oligonucleotide primers were designed to amplify a 438-bp fragment of the com1 gene encoding a 27-kda outer membrane protein of c. burnetii. the primers amplified the predicted fragments of 21 various strains of c. burnetii but did not react with dna samples from other microorganisms. the 438-bp amplification products could be digested with restriction enzymes sspi and sali. the utility ... | 1998 | 9431924 |
| comparative analysis of infrequent-restriction-site pcr and pulsed-field gel electrophoresis for epidemiological typing of legionella pneumophila serogroup 1 strains. | two methods were compared for the analysis of 48 unrelated and epidemiologically related legionella pneumophila serogroup 1 isolates. these are the infrequent-restriction-site pcr (irs-pcr) assay with adapters designed for xbai and psti restriction sites and the pulsed-field gel electrophoresis (pfge) analysis determined after dna restriction with sfii. both methods demonstrated a high level of discrimination with a similar capacity for differentiating 23 of the 24 unrelated isolates. pfge analy ... | 1998 | 9431941 |
| detection of toxin-producing cyanobacteria by use of paramagnetic beads for cell concentration and dna purification. | early detection of water blooms caused by potential toxin-producing cyanobacteria is important in environmental monitoring. we present a new nucleic acid-based method for detection of cyanobacteria in water that utilizes the same paramagnetic solid phase (beads) for both bacterial cell concentration and subsequent dna purification. in the cell concentration step, the beads were attracted to a magnet after cell adsorption (in an alcohol- and salt-containing solution), and the supernatant was remo ... | 1998 | 9435059 |
| heterogeneity in the attachment and uptake mechanisms of the legionnaires' disease bacterium, legionella pneumophila, by protozoan hosts. | invasion and intracellular replication of legionella pneumophila within protozoa in the environment plays a major role in the transmission of legionnaires' disease. intracellular replication of l. pneumophila within protozoa occurs in a rough endoplasmic reticulum (rer)-surrounded phagosome (y. abu kwaik, appl. environ. microbiol. 62:2022-2028, 1996). since the subsequent fate of many intracellular pathogens is determined by the route of entry, we compared the mechanisms of attachment and subseq ... | 1998 | 9435069 |
| protozoan bacterivory and escherichia coli survival in drinking water distribution systems. | the development of bacterial communities in drinking water distribution systems leads to a food chain which supports the growth of macroorganisms incompatible with water quality requirements and esthetics. nevertheless, very few studies have examined the microbial communities in drinking water distribution systems and their trophic relationships. this study was done to quantify the microbial communities (especially bacteria and protozoa) and obtain direct and indirect proof of protozoan feeding ... | 1998 | 9435076 |
| production of respirable vesicles containing live legionella pneumophila cells by two acanthamoeba spp. | two acanthamoeba species, fed at three temperatures, expelled vesicles containing living legionella pneumophila cells. vesicles ranged from 2.1 to 6.4 microns in diameter and theoretically could contain several hundred bacteria. viable l. pneumophila cells were observed within vesicles which had been exposed to two cooling tower biocides for 24 h. clusters of bacteria in vesicles were not dispersed by freeze-thawing and sonication. such vesicles may be agents for the transmission of legionellosi ... | 1998 | 9435080 |
| efficacy of thermal treatment and copper-silver ionization for controlling legionella pneumophila in high-volume hot water plumbing systems in hospitals. | thermal treatment and copper-silver ionization are often used for controlling legionella pneumophila in high-volume hospital plumbing systems, although the comparative efficacies of these measures in high-volume systems are unknown. | 1997 | 9437482 |
| biochemical and genetic characterization of an fk506-sensitive peptidyl prolyl cis-trans isomerase from a thermophilic archaeon, methanococcus thermolithotrophicus. | a peptidyl prolyl cis-trans isomerase (ppiase) was purified from a thermophilic methanogen, methanococcus thermolithotrophicus. the ppiase activity was inhibited by fk506 but not by cyclosporine. the molecular mass of the purified enzyme was estimated to be 16 kda by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and 42 kda by gel filtration. the enzyme was thermostable, with the half-lives of its activity at 90 and 100 degrees c being 90 and 30 min, respectively. the catalytic effici ... | 1998 | 9440528 |
| conjugative transfer by the virulence system of legionella pneumophila. | legionella pneumophila, the causative agent of legionnaires' pneumonia, replicates within alveolar macrophages by preventing phagosome-lysosome fusion. here, a large number of mutants called dot (defective for organelle trafficking) that were unable to replicate intracellularly because of an inability of the bacteria to alter the endocytic pathway of macrophages were isolated. the dot virulence genes encoded a large putative membrane complex that functioned as a secretion system that was able to ... | 1998 | 9452389 |
| the role of sialic acid in opsonin-dependent and opsonin-independent adhesion of listeria monocytogenes to murine peritoneal macrophages. | the adhesion of listeriae to host cells employs mechanisms which are complex and not well understood. listeria monocytogenes is a facultative intracellular pathogen responsible for meningoencephalitis, septicemia, and abortion in susceptible and immunocompromised individuals. subsequent to colonization and penetration of the gut epithelium, the organism attaches to resident macrophages and replicates intracellularly, thus evading the humoral immune system of the infected host. the focus of these ... | 1998 | 9453618 |