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Biomedical subjects

W B Cherry

Publications and source records attributed to W B Cherry.

At least 19 recordsLinked to original sources
PubMed1984

Legionnaires' disease: the epidemiology of two outbreaks in Burlington, Vermont, 1980.

Eighty-five cases of Legionnaires' disease were diagnosed in two major outbreaks at a large regional medical center in Burlington, Vermont, in the summer of 1980. Cases in both outbreaks were positive for Legionella pneumophila, serogroup 1 by culture, serology, or direct fluorescent antibody tests. All cases had spent time in the city of Burlington in the 10 days before the onset of symptoms. Cases in both outbreaks were both hospital- and community-acquired. A case-control study identified no common in-hospital exposure, including shower use, that was associated with illness. Cases without previous exposure to the hospital were more likely to occur in persons with residences in neighborhoods just downwind of cooling tower A, but not throughout the municipal water system. Epidemiologic and environmental studies supported the association of this cooling tower, located 150 m from the hospital, with both outbreaks. Maintenance employees who worked with tower A had higher Legionella titers than those who worked with a comparison tower located 1.6 km away. Aerosolization of L. pneumophila by tower A and airborne spread to the hospital and community are postulated. The distance of airborne transmission of L. pneumophila in these consecutive outbreaks is greater than previously reported.

Cross Infection↗
PubMed1983

Legionella oakridgensis: unusual new species isolated from cooling tower water.

We describe a new species of Legionella represented by 10 strains isolated from industrial cooling towers. Legionella oakridgensis differed genetically from the other seven species of Legionella in DNA hybridization studies and differed serologically in direct fluorescent-antibody tests. The new species, unlike all other species except L. jordanis, did not require added L-cysteine for growth in serial transfer on charcoal-yeast extract agar. L. oakridgensis, as well as three other species tested, required L-cysteine for primary isolation from animal tissues. L. oakridgensis was the only species of Legionella that failed to produce alkaline phosphatase at pH 8.5. In all other respects, it resembled other species of Legionella, including having a high content of branched-chain cellular fatty acids and being pathogenic for guinea pigs. These bacteria have not yet been associated with human disease, but they are potential causes of legionellosis.

Air Conditioning↗
PubMed1983

Determination of antigenic relationships among legionellae and non-legionellae by direct fluorescent-antibody and immunodiffusion tests.

Six isolates, five from water samples and one from a human tracheal swab taken at autopsy, reacted strongly with working dilutions of Legionella fluorescent-antibody conjugates. Of these, two isolates of Pseudomonas fluorescens (EB and CDC93), one isolate of the Flavobacterium-Xanthomonas group (CDC65), and one isolate of P. alcaligenes (CDC11) reacted with Legionella pneumophila serogroup 1 conjugate. P. alcaligenes ABB 50 reacted with an L. pneumophila serogroup 3 conjugate and of P. maltophilia reacted with the L. micdadei conjugate. Antisera and labeled conjugates were prepared for these new cross-reacting isolates, and their relationships to the legionellae were examined by direct fluorescent-antibody and immunodiffusion tests. A nonreciprocal cross-reaction existed between L. micdadei and P. maltophilia and also between serogroups 3 of L. pneumophila and P. alcaligenes ABB50. Of the four isolates that reacted with serogroup 1 of L. pneumophila, P. fluorescens CDC93 had the strongest relationship, and the other three had only minor relationships. Although cross-reactivity among non-legionellae and legionellae has not been a major problem, these findings are relevant to the interpretation of direct fluorescent-antibody tests for detecting these bacteria.

Antigens, Bacterial↗
PubMed1982

Legionella jordanis: a new species of Legionella isolated from water and sewage.

Legionella jordanis sp. nov., as found in two cultures, is described. One isolate was from river water in Indiana and the other isolate was from sewage in DeKalb County, Ga. The former is the type strain of the species, and is designated BL-540 (ATCC 33623). L. jordanis had a partial relationship to L. bozemanii by direct fluorescent-antibody tests but was unrelated to L. pneumophila, L. dumoffii, L. micdadei, L. gormanii, or L. longbeachae. Legionella phenotypic characteristics, including large amounts of branched-chain cellular fatty acids, were shown by the isolates. Studies of DNA relatedness showed that the two cultures of L. jordanis were only slightly related to the six previously described species of Legionella but were more than 90% related to each other. Indirect fluorescent-antibody tests with human sera suggested that unrecognized human infections with L. jordanis may be occurring.

DNA, Bacterial↗
PubMed1981

Ecological distribution of Legionella pneumophila.

Bacteria were concentrated 500-fold from 20-liter water samples collected from 67 different lakes and rivers in the United States. The data suggest that Legionella pneumophila is part of the natural aquatic environment and that the bacterium is capable of surviving extreme ranges of environmental conditions. The data further demonstrate the effectiveness of the direct fluorescent-antibody technique for detecting L. pneumophila in natural aquatic systems. Smears of the concentrated samples were screened microscopically for serogroups of L. pneumophila by the direct fluorescent-antibody technique. Virtually all of the 793 samples were found to be positive by this method. The 318 samples containing the largest numbers of positive bacteria which were morphologically consistent with L. pneumophila were injected into guinea pigs for attempted isolations. Isolates were obtained from habitats with a wide range of physical, chemical, and biological parameters. Samples collected monthly from a thermally altered lake and injected into guinea pigs demonstrated a seasonality of infection, with the highest frequency of infection occurring during the summer months.

Animals↗
PubMed1981

Isolation of Legionella pneumophilia from cooling tower water by filtration.

Methods are described for detection of Legionella pneumophila in cooling tower water or other water sources by direct fluorescent-antibody staining. A procedure for isolation of Legionella bacteria from water samples by guinea pig inoculation is described. Two different serogroups of L. pneumophila were isolated repeatedly from one of the cooling towers.

Air Conditioning↗
PubMed1981

Characteristics of environmental isolates of Legionella pneumophila.

Thirty-eight cultures of Legionella pneumophila isolated from surface waters were characterized by their morphological, tinctorial, biochemical, and serological properties and by their ability to produce disease in guinea pigs. Their susceptibility to antimicrobial agents also was tested. When they were compared with clinical isolates, no important differences were found between cultures from the two sources. Sodium hippurate hydrolysis, gelatin liquefaction, pigment formation, and beta-lactamase and alkaline phosphatase activity were useful in differentiating the four described species of Legionella. Hydrolysis of diacetylfluorescein and the inability to reduce nitrate help to distinguish Legionella species from other gram-negative bacterial rods.

Alkaline Phosphatase↗
PubMed1981

Legionellosis.

Explore the source record for details and available documents.

Agglutination Tests↗
PubMed1980

Growth of Legionella pneumophila in association with blue-green algae (cyanobacteria).

Legionella pneumophila (Legionnaires disease bacterium) of serogroup 1 was isolated from an algal-bacterial mat community growing at 45 degrees C in a man-made thermal effluent. This isolate was grown in mineral salts medium at 45 degrees C in association with the blue-green alga (cyanobacterium) Fischerella sp. over a pH range of 6.9 to 7.6. L. pneumophila was apparently using algal extracellular products as its carbon and energy sources. These observations indicate that the temperature, pH, and nutritional requirements of L. pneumophila are not as stringent as those previously observed when cultured on complex media. This association between L. pneumophila and certain blue-green algae suggests an explanation for the apparent widespread distribution of the bacterium in nature.

Bacteria↗
PubMed1980

Direct immunofluorescent detection of Legionella pneumophila in respiratory specimens.

Respiratory secretions from patients with clinically suspected Legionnaires pneumonia were examined by direc immunofluorescent tests at the Medical Center Hospital of Vermont and at the Center for Disease Control. No fluorescent bacteria were found by either laboratory in eight specimens from eight patients who were seronegative. Twenty specimens were obtained from seven patients who had serologically confirmed Legionnaires disease. Four of the seven cases were identified at the Medical Center Hospital of Vermont, and six of the seven were identified at the Center for Disease Control. Of 20 specimens, 8 were positive at the Center for Disease Control (six or more bacilli per slide), and 7 specimens were suspicious (one to five bacilli per slide); at the Medical Center Hospital of Vermont, 4 of 20 specimens were positive, and 2 were suspicious. The inclusion of a rhodamine-conjugated counterstain at the Center for Disease Control facilitated the examination and may have improved the sensitivity. Smears from transtracheal aspirates, bronchoscopic aspirates, transcutaneous lung aspirates, pleural fluids, and tracheal aspirate-expectorated sputum produced positive results. Several specimens contained fluorescing bacilli when stained for serogroup 2 as well as serogroup 1, perhaps reflecting the presence of cross-reacting antigens in vivo.

Bacteria↗
PubMed1979

Isolation of Legionella pneumophila from nonepidemic-related aquatic habitats.

Continuous centrifugation of large volumes of water from natural southeastern lakes allowed quantitative detection of Legionella pneumophila by direct immunofluorescent staining. Positive samples were injected intraperitoneally into guinea pigs, and the L. pneumophila were isolated and identified by their morphological, cultural, physiological, and serological characteristics.

Animals↗
PubMed1979

Rapid diagnosis of Legionnaires' disease by direct immunofluorescent staining.

A blind reading of direct immunofluorescent staining of sputum smears was positive in five of 21 patients with Legionnaires' disease and none of 47 control patients. Positive slides showed from eight organisms per smear (one slide) to 20 to 100 organisms per oil-immersion (magnification, 100) field (three slides). Two of the positive specimens were obtained through an endotracheal tube, one at bronchoscopy, and the other positive slides were from expectorated specimens. In addition, two open-lung biopsies and a bronchial lavage sediment from three confirmed cases of Legionnaires' disease were positive by direct immunofluorescent staining for Legionnaires' disease bacterium.

Fluorescent Antibody Technique↗
PubMed1979

Legionnaires' disease in patients with associated serious disease.

Of nine patients with Legionnaires' disease, seven were receiving corticosteroids, and all nine had serious underlying diseases. Direct immunofluorescent examination of respiratory secretions, including sputum and transtracheal aspirates, showed the Legionnaires' disease (LD) bacterium in five of seven patients who seroconverted and in a sixth patient with a single elevated titer to the LD bacterium. All nine patients received erythromycin therapy, and five survived. Two patients showed persistence of their infection after receiving 2 weeks of erythromycin therapy, and two patients developed pulmonary abscesses. These cases of Legionnaires' disease show the occurrence of pulmonary abscesses, the possibility of relapse after giving only 2 weeks of erythromycin therapy, and the utility of direct immunofluorescence for early diagnosis.

Adrenal Cortex Hormones↗
PubMed1978

Detection of Legionnaires disease bacteria by direct immunofluorescent staining.

Antisera and fluorescein isothiocyanate conjugates prepared for five strains of the Legionnaires bacteria were tested in both homologous and heterologous staining reactions with 10 isolates of the organism from patients in seven geographic areas. The strains were related but not identical as judged by the results of direct immunofluorescence staining. The conjugates were successfully used to detect Legionnaires disease bacteria in Formalin-fixed lung scrapings, in histological sections, and in fresh lung tissue obtained at biopsy or autopsy. In addition, the labeled antibodies are valuable for staining suspected cultures of the bacterium and for searching for the source of these organisms in soil, water, and other environmental niches. The reagents are highly specific for detecting the Legionnaires organism in clinical specimens.

Bacteria↗
PubMed1977

Increased recovery of salmonellae from environmental samples enriched with buffered peptone water.

The incidence and persistence of salmonellae in weather pools on the top of Stone Mountain were investigated with lactose and buffered peptone water used as pre-enrichment broths. A total of 162 samples were collected from 16 weather pools over a 3-month period. The use of buffered peptone water increased the recovery of salmonellae by approximately 25%. The combined use of direct enrichment in tetrathionate broth containing brilliant green dye and pre-enrichment in buffered peptone water followed by enrichment in tetrathionate broth made it possible to detect all 37 of the contaminated samples. All of the isolates were Salmonella bareilly, the only serotype recovered in a previous study. All but one of the isolations were made from moist or wet samples. S. bareilly was isolated from rabbit dung and litter collected near the weather pools, but attempts to trap rabbits for study were unsuccessful. Random samples taken along a side of the mountain yielded S. bareilly in weather pools within the upper third of the mountain; below this level, S. weslaco and S. memphis were recovered, but not S. bareilly.

Animals↗
PubMed1977

Salmonellae in health foods.

Various health food products of different brands were purchased from stores in the metropolitan Atlanta area. These foods were examined for the presence of salmonellae by fluorescent-antibody and cultural methods. Included in the study were tablets of alfalfa, parsley, kelp, wheat bran, enzyme, bone meal, and vitamins. Beef liver powder and tablets and granola cereal were also studied. Salmonella minnesota, Salmonella anatum, and Salmonella derby were isolated from two of three lots of beef liver powder from one manufacturer. All other products were negative.

Animals↗