Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023241 (Legionella)
 6,990 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Although cases of community-acquired Legionnaires' disease have been epidemiologically linked to residential water supplies, the risk of acquiring Legionnaires' disease from exposure to Legionella pneumophila in residential water systems is uncertain. The residential water supplies of 218 members of the American Legion in six different geographical areas in Pittsburgh were cultured for L. pneumophila. Residents of the homes provided a recent medical history and a blood sample for detection of antibodies to legionella. A urine sample for legionella urinary antigen testing was also requested from individuals residing in legionella-positive homes and individuals with a positive antibody test. Six percent (14/218) of the homes yielded L. pneumophila (range within six areas 0-22%). Lower hot water tank temperature was significantly associated with legionella positivity (P less than 0.01). Analysis of water samples for mineral content showed no association between legionella positivity and concentrations of calcium and magnesium. Water samples from the area where 22% of the homes surveyed were positive for legionella had a higher iron content than water samples from the other areas tested. None of the individuals residing in legionella-positive homes showed elevated antibody titres to legionella or the presence of legionella antigen in urine. For the immunocompetent hosts, the risk of contracting Legionnaires' disease from exposure to contaminated household water supplies in the Pittsburgh area appears to be low.
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PMID:Legionella pneumophila in residential water supplies: environmental surveillance with clinical assessment for Legionnaires' disease. 149 72

Survival studies were conducted on Legionella pneumophila cells that had been grown intracellularly in Acanthamoeba polyphaga and then exposed to polyhexamethylene biguanide (PHMB), benzisothiazolone (BIT), and 5-chloro-N-methylisothiazolone (CMIT). Susceptibilities were also determined for L. pneumophila grown under iron-sufficient and iron-depleted conditions. BIT was relatively ineffective against cells grown under iron depletion; in contrast, iron-depleted conditions increased the susceptibilities of cells to PHMB and CMIT. The activities of all three biocides were greatly reduced against L. pneumophila grown in amoebae. PHMB (1 x MIC) gave 99.99% reductions in viability for cultures grown in broth within 6 h and no detectable survivors at 24 h but only 90 and 99.9% killing at 6 h and 24 h, respectively, for cells grown in amoebae. The antimicrobial properties of the three biocides against A. polyphaga were also determined. The majority of amoebae recovered from BIT treatment, but few, if any, survived CMIT treatment or exposure to PHMB. This study not only shows the profound effect that intra-amoebal growth has on the physiological status and antimicrobial susceptibility of L. pneumophila but also reveals PHMB to be a potential biocide for effective water treatment. In this respect, PHMB has significant activity, below its recommended use concentrations, against both the host amoeba and L. pneumophila.
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PMID:Relationship between Legionella pneumophila and Acanthamoeba polyphaga: physiological status and susceptibility to chemical inactivation. 151 90

Legionella pneumophila serogroup 1 (Lp1) strains isolated from patients and hot water supplies in different locations of Germany were subtyped using seven monoclonal antibodies (mabs) in the indirect immunofluorescence test (IFA) and in part, using a dot blot assay. Four of these mabs were produced in Dresden. Three mabs (mab 33G3, mab 32A12 and mab 144c2) were kindly supplied by J. Joly, Quebec, Canada. Altogether, seven antigenic variants were found among Lp1 strains isolated in Germany. Patient strains belonged to the Philadelphia, Benidorm, Knoxville, France, Olda-Heysham and Bellingham subgroups, whereas environmental isolates reacted like the Bellingham, Oxford, Philadelphia, Knoxville and France strains. The majority of patient strains (15 out of 26, 58%) reacted with our mab 3/1 (corresponding to mab 2 of the standard panel), but only 26 out of 118 environmental strains (22%) isolated from 4 of 15 hot water supplies did so (p less than 0.05). The majority of water-borne Lp1 strains reacted with a mab specific of the Bellingham subgroup. Three water systems under study were associated with human legionellosis. Two of them contained Bellingham-like strains, one Philadelphia-like legionellae.
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PMID:Subtyping of Legionella pneumophila serogroup 1 strains isolated in Germany using monoclonal antibodies. 152 Sep 76

A hospital warm water system was monitored for the presence and distribution of legionellae. Subtyping of ten selected Legionella pneumophila isolates, originating from four different sites in the system by using serogroup specific antisera in an indirect immunofluorescence test, revealed that nine of the ten isolates belong to serogroup 6, while the remaining one was serogroup 10. Two monoclonal antibodies (mAbs) specific for a subgroup of serogroup 6 strains were further used for characterization. None of the strains reacted with these mAbs. Genome analysis by elaborating NotI profiles using the pulsed field gel electrophoresis (PFGE) technique revealed that nearly all serogroup 6 isolates derived from different sites, including a new building connected by a ring pipe, were identical according to restriction fragment patterns. The patterns were distinguishable from those of the two L. pneumophila serogroup 6 reference strains, and from that of the L. pneumophila serogroup 10 isolate. These data argue for a relatively homogeneous L. pneumophila serogroup 6 population in the entire water system.
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PMID:Distribution of legionellae in a hospital water system: prevalence of immunologically and genetically related Legionella pneumophila serogroup 6 isolates. 152 52

Ten days after starting military service in a police barracks a 25-year-old man developed left middle and lower lobe pneumonia which did not respond to ampicillin (8 g daily) and gentamycin (120 mg daily). Parenteral administration of doxycycline (100 mg daily) was equally ineffective. However, the fever fell on administration of cefotiam (4 g daily). Antibody tests demonstrated Legionella pneumophila serogroup 1 as the causative organism. Because of the confined accommodation of the conscripts the source of the infection was thought to be the hot water system in the barracks. In two other policemen the demonstration of antibodies and of urine antigens confirmed Legionella infection as cause of an acute respiratory illness (Pontiac disease). Legionella pneumophila serogroup 1 subtype Philadelphia, 1-8 colony-forming units per ml, was isolated from six of 14 hot water samples in the barracks. This subtype possesses a virulence-associated antigen which is found in the majority of patient isolates of Legionella pneumophila serogroup 1.
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PMID:[A minor epidemic due to Legionella pneumophila serogroup 1]. 154 2

We cultured potable water from seven institutions (six hospitals and one medical school) every 2 weeks for 6 months for Legionella pneumophila. All of the institutions were located close to each other and received water from the same freshwater source. Two institutions (the medical school and hospital F, a maternity hospital) never had L. pneumophila isolated from their potable water. The remaining five had 17 to 72% of their water samples positive for L. pneumophila. Most of the isolates were serogroup 1; however, in hospital B serogroup 5 accounted for 56% of the isolates. Oxford and OLDA monoclonal antibody subtypes of L. pneumophila serogroup 1 coexisted in four of the five institutions, while subtype France only was found in one institution. All 10 isolates from this institution lacked plasmids. The other four institutions had Legionella populations with plasmid profiles II, III, and VI. Two of these institutions also had isolates with no plasmids. The distribution of the plasmid types was significantly different for all institutions except C and D. The distribution of monoclonal antibody subtypes was significantly different for L. pneumophila isolates recovered from institutions C and D. There were no characteristics that distinguished the culture-positive institutions from the culture-negative areas. We conclude that diverse populations of L. pneumophila exist within these institutions despite their geographic proximity and identical potable water source.
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PMID:Diverse populations of Legionella pneumophila present in the water of geographically clustered institutions served by the same water reservoir. 155 72

From 10 October through 13 November 1989, 33 patients were hospitalized with legionnaires' disease in Bogalusa, Louisiana. A case-control study revealed case-patients were more likely than controls to have shopped at grocery store A (93% vs. 52%; odds ratio [OR], 11.6; 95% confidence interval [CI], 2.3-78.7) in the 10 days before illness. Among those who shopped at grocery store A, case-patients were more likely to shop for greater than 30 min (OR, 18.0; CI, 2.0-407.8) and to buy produce items located close to an ultrasonic mist machine (OR, 7.4; CI, 1.3-56.2). Employees of grocery store A were more likely than employees of other grocery stores in Bogalusa to have antibody titers of greater than or equal to 1:128 to Legionella pneumophila serogroup 1 (Lp-1; relative risk, 2.9; CI, 1.3-6.8). Lp-1 was isolated from water in the reservoir of the mist machine. The monoclonal antibody subtype of the isolate was identical to organisms identified in two patients. Viable Lp-1 was isolated from mist produced by the machine. Aerosols from a grocery store mist machine were the source of this outbreak.
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PMID:Communitywide outbreak of Legionnaires' disease associated with a grocery store mist machine. 155 3

Water samples taken from hot water springs, from the water distribution system and from various places of consumption of thermal water were collected in an Austrian spa. 56.5% of the samples contained Legionella; serogroups 1, 3 and 5 of Legionella pneumophila were most frequently identified. The large number of positive Legionella samples indicates a potential risk of infection to patients, especially those undergoing inhalation treatment with thermal water, or those using a whirlpool or taking a shower. In those inhalators actually in use, no Legionella could be detected. Thus they are no source of infection when they are maintained and serviced properly. Thermal disinfection and service checks at regular intervals are suggested for the contaminated systems.
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PMID:[Detection of legionellae in thermal water]. 155 6

Helicobacter pylori is associated with gastritis and peptic ulcer disease in humans. We have identified a homolog of the chaperonin cpn60 family of heat shock proteins in H. pylori, referred to as Hp54K. Hp54K, purified from water-extractable H. pylori proteins, migrated as a single band at 54 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Its native molecular mass was 740 kDa; thus, Hp54K apparently comprises a 14-mer. The N-terminal 33 residues of Hp54K exhibited 60.6, 57.6, 54.5, 54.5, 51.5, and 51.5% identity with corresponding sequences in the following cpn60 homologs: HtpB (Legionella pneumophila), P1 (human mitochondria), GroEL (Escherichia coli), BA60K (Brucella abortus), HypB (Chlamydia trachomatis), and the 65-kDa immunodominant protein of Mycobacterium bovis BCG, respectively. Hp54K was the only protein recognized in whole-cell preparations of H. pylori by immunoblotting using monospecific antisera against cpn60 homologs from L. pneumophila, E. coli, C. trachomatis, and M. bovis BCG. Antiserum against Hp54K recognized proteins with molecular masses of 50 to 60 kDa in a large number of gram-negative bacteria, consistent with the known highly conserved nature of cpn60 proteins. Hp54K is a major protein and is immunogenic in humans infected with H. pylori. Thus, Hp54K shares many similarities with known cpn60 homologs. On the basis of the proposed role of other cpn60 proteins in induction of chronic inflammation, immune cross-reactivity between Hp54K and gastric tissue may provide an important link between H. pylori infection and gastritis.
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PMID:Identification and purification of a cpn60 heat shock protein homolog from Helicobacter pylori. 156 86

We determined the natural history of the colonization of our hospital's potable water by culturing water approximately biweekly from 20 sites throughout the hospital for 4 years. Overall, 545 (24.7%) of the 2200 samples grew Legionella pneumophila. During hyperchlorination, 11.7% of the samples were positive while 41.6% were positive in the absence of chlorination. There was no seasonal trend towards positivity, but there was marked inter-site variation in the semi-quantitative culture results. However, a single strain of legionella (as defined by plasmid profiling) tended to persist at a site. Such a site was a unique ecological niche in that different sites in the same wing were populated by distinct strains. The two wings of our hospital had a significantly different distribution of strains of legionella-plasmid profile type III predominated in the Victoria Wing while types II and VI predominated in Centennial Wing. Twenty-four of our 28 cases of nosocomial Legionnaires' disease occurred in the Centennial Wing. Three of the four cases in the Victoria Wing were caused by plasmid profile type III while 18 of the 24 isolates from patients who acquired their infection in the Centennial Wing were type II. We conclude that each water outlet serves as its own ecological niche of L. pneumophila.
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PMID:Each water outlet is a unique ecological niche for Legionella pneumophila. 158 68


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