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

Infection by Legionella pneumophila is believed to depend upon its ability to multiply within host alveolar macrophages. To investigate this, a site-specific mutation was introduced into a gene (mip) that encodes a 24,000-Da surface protein; an 80-fold loss of infectivity for both U937 cells and explanted human alveolar macrophages was observed. Further phenotypic analysis of the mutant strain has failed to show alterations in bacterial factors (e.g., proteinase, lipopolysaccharide) that have suspected roles in virulence. To substantiate that this mutation also results in reduced virulence in animals, the lethality and clinical illnesses produced by the parent and mutant L. pneumophila strains were compared in guinea pigs after intratracheal inoculation. The mutant strain produced fewer illnesses, slower-progressing disease, and fewer lethal infections than either the parent strain or a derivative of the mutant strain with the wild-type mip gene reintroduced. When sublethal inocula of the three strains were used, the mutant bacteria were recovered in slightly lower numbers from lung homogenates and in significantly lower numbers from the spleen, at 48 h, than were the other two test strains. Thus mip seems to be necessary for full virulence of L. pneumophila and may represent the first genetically defined virulence factor in this species.
 ...
PMID:A mutation in the mip gene results in an attenuation of Legionella pneumophila virulence. 235 88

A microbiological and epidemiological investigation at the Infectious Diseases Hospital in Turin, Italy, demonstrated Legionella pneumophila serogroup 3 at 10(2) to greater than 4 X 10(3) cfu l-1 from 24 of 32 hot water samples collected from hand-basins in six separate buildings. A sample taken from the public water supply, and a hot water sample (80 degrees C) collected from hot water tanks, did not yield legionellas. Legionella pneumophila serogroup 3 was found in samples taken at the first point of mixed hot and cold water (50 degrees C) at 3 X 10(2) cfu l-1. 12 of 26 samples from the shower-heads yielded 10(3) to 2.5 X 10(5) cfu l-1 and one of 12 water samples from oxygen bubble humidifiers tested yielded 1.6 X 10(4) cfu l-1. No other legionellas species or serogroups of Legionella pneumophila were isolated during the study. No cases of nosocomial pneumonia were detected among 3653 patients' records, nor was there serological evidence of Legionella infection in the 180 patients tested.
 ...
PMID:Endemicity of Legionella pneumophila serogroup 3 in a hospital water supply. 256 58

A 43-year-old woman was hospitalized for fulminant pericarditis. During diagnostic work-up, an as yet unknown bronchial carcinoma was detected. In the pericardial exudate Legionella pneumophila serogroup 3 was demonstrated by direct fluorescent antibody technique and by culture. In a lung biopsy L. pneumophila serogroup 3 was found, too. Using an antigen-ELISA for L. pneumophila serogroup 1, antigenuria was demonstrated. In cases of pericarditis negative for common bacterial pathogens, all diagnostic tests for legionellae, e.g. culture, antigen detection in pericardial, pleural effusion and urine and antibody detection should be included in the diagnostic programme.
Infection
PMID:Isolation of Legionella pneumophila serogroup 3 from pericardial fluid in a case of pericarditis. 261 28

The availability of new biotechnologies has led to the prediction that new or improved vaccines can be developed for 27 diseases within the next decade. The reasons why such optimism cannot be extended to the availability of vaccines for many other infectious diseases are considered by reviewing the steps in vaccine development, from identification of the etiologic agent to construction of attenuated or inactivated vaccines. Impediments to development may exist or arise at any point in this pathway (e.g., multiplicity of serotypes, inability to cultivate the pathogen, multistage life cycles with multiple antigens, unpredictability of epidemics, inadequate knowledge of pathogenesis and immunity, fear of gene splicing, need for an adjuvant, and lack of profitability). Diseases for which vaccines are not likely to be available in the next decade include trachoma, onchocerciasis, pneumonia due to Legionella and to mycoplasmas, amebiasis and giardiasis, schistosomiasis, syphilis, chlamydial urethritis, trypanosomiasis, leishmaniasis, and filariasis, and non-A, non-B hepatitis.
 ...
PMID:Impediments to the development of additional vaccines: vaccines against important diseases that will not be available in the next decade. 266 4

Current microbiologic techniques (determinations of minimal inhibitory and/or microbicidal concentrations) are unable to delineate the true role of anti-infectious drugs in the treatment of human infections due to intracellular pathogens. The prediction and evaluation of the efficacy of quinolones against intracellular pathogens requires information on four different steps. (1) Quinolones should be able to penetrate phagocytes; intramacrophagic concentration is highly dependent on serum pharmacokinetics; finally, the best quinolone should have the longest serum half-life and reach highest maximum serum concentrations. (2) The evaluation of antibacterial activity requires an adequate cellular model (e.g., multiplication of Legionella pneumophila within human monocyte-derived macrophages). (3) The prediction of drug efficacy requires an experimental animal model. (4) Clinical trials in human disease are necessary. This stage is difficult when the evaluation concerns severe infectious diseases because the rarity of these diseases makes random clinical trials difficult. In this paper we describe methodologies for assessing the efficacy of quinolones against intracellular bacterial pathogens with a particular focus on Legionella pneumophila.
 ...
PMID:Use of fluoroquinolones for intracellular pathogens. 267 63

During the first nine months of 1987, the bacteriological and virological tests as well as the indirect fluorescence test to Legionella pneumophila were performed in 40 children with bronchopneumonia (one- or both-sided) or pleuropneumonia and in 10 children with protracted bronchitis. In a 15 month old boy we have proved (by titer dynamics) the infection with Legionella pneumophila serotype 5, and in a 15 month old girl and in a 16 month old boy serotype 1. The infection was sporadic and the possible source of infection was unknown. The course of the disease was not wasting and the infection was accompanied with fever. The patients had an increased sedimentation rate of red cells and leukocytosis. All the other laboratory findings were within normal limits. In seven children seropositiveness 1:256 to Legionella pneumophila serotype 1, and in two children an increased titer to adenovirus was proved. The high titer to Legionella pneumophila in those seven children indicates an early contact with the causal agent. The patients were successfully treated with cefuroxim, which is not the drug of choice. Infection due to Legionella pneumophila in children does not exhibit a clinical or laboratory characteristic features that differ from those of the other respiratory diseases in children. It means that Legionnaires' disease in children with intact immunity is not the wasting illness. We stress the importance of using serologic examination to Legionella pneumophila as a routine procedure in the aetiological diagnosis of respiratory diseases in children.
 ...
PMID:[Legionnaires' disease in children]. 279 76

Two patients with Legionella pneumophila infection (serogroup 1) associated with a reactivated cytomegalovirus infection are described. Predisposing underlying factors were not evident.
Infection
PMID:Legionella pneumophila pneumonia associated with reactivation of cytomegalovirus infection. 300 Sep 47

The antibacterial activity of ofloxacin against Enterobacteriaceae, Pseudomonas aeruginosa, Haemophilus influenzae, Branhamella catarrhalis, and Neisseria gonorrhoeae was comparable to norfloxacin and enoxacin, and far exceeded the activity of pipemidic acid and nalidixic acid. The activity of ofloxacin was two to eight times less than that of ciprofloxacin. Ofloxacin was more active against Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pneumoniae, Acinetobacter spp., Legionella spp., and Bacteroides fragilis, than norfloxacin, enoxacin, pipemidic acid and nalidixic acid, and the activity of ofloxacin was comparable to that of ciprofloxacin. Ofloxacin was two to seven times more effective than norfloxacin in systemic infections in mice with S. aureus, Escherichia coli, Serratia marcescens and P. aeruginosa. Ofloxacin strongly inhibited DNA supercoiling activity of DNA gyrase purified from E. coli KL-16. There is a parallel relationship between antibacterial activity of ofloxacin and its inhibitory action against DNA gyrases from ofloxacin-susceptible and ofloxacin-resistant clinical isolates of E. coli. These results indicate that the high bactericidal action of ofloxacin and the related new quinolone agents can be explained by their potent inhibitory activities against DNA gyrase in bacterial cells.
Infection 1986
PMID:Antibacterial activity of ofloxacin and its mode of action. 302 66

42 dental units in 35 dentist practices were bacteriologically examined. Legionella of the species Legionella pneumophila--SG1 could be isolated from 4 dental units. Infection can occur during inhalation of finest aerosols, which are formed during the use of dental turbines and sprays.
 ...
PMID:[Demonstration of Legionella pneumophila in dental units]. 310 61

The University of Iowa Hospitals and Clinics is located in the center of the United States in Eastern Iowa, has 1,000 hospital beds, and is the largest university owned teaching hospital in the country. Over 35,000 patients are admitted each year. The infection control efforts began in 1969 and were broadened in 1976 with the establishment and implementation of the Program of Epidemiology directed by W.J. Hierholzer, Jr., M.D., hospital epidemiologist. Hospital-wide surveillance is routinely performed by three and a half full-time equivalent LPN practitioners who assess problems and evaluate data essential to realistic identification of nosocomial infection rates, implementation of controls and evaluation of control measures. Nosocomial infection surveillance, utilizing modified CDC criteria, has been performed since July 1976. Ward rounds are made by staff, utilizing nursing care and medication Kardex's, microbiology, hematology and X-ray reports. Importantly, the surveillance system is being validated by concurrent prospective surveys to determine the sensitivity and specificity of reporting data. Outbreaks/epidemics of infections, such as Legionella pneumonia, diarrhea of unknown species, and wounds, as well as burns from manufactured changes in cautery grounds, have been identified and controlled before they have become major epidemics. Surveillance has identified one epidemic per 10,000 patients admitted.(ABSTRACT TRUNCATED AT 250 WORDS)
Infection 1988
PMID:Organization and operation of the hospital-infection-control program of the University of Iowa Hospitals and Clinics. 322 May 85


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>