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D J Brenner

Publications and source records attributed to D J Brenner.

At least 181 records · Page 10Linked to original sources
PubMed1991

Proposal of Afipia gen. nov., with Afipia felis sp. nov. (formerly the cat scratch disease bacillus), Afipia clevelandensis sp. nov. (formerly the Cleveland Clinic Foundation strain), Afipia broomeae sp. nov., and three unnamed genospecies.

On the basis of phenotypic characterization and DNA relatedness determinations, the genus Afipia gen. nov., which contains six species, is described. The type species is Afipia felis sp. nov. (the cat scratch disease bacillus). Afipia clevelandensis sp. nov., Afipia broomeae sp. nov., and three unnamed not associated with cat-borne disease. All but one strain (Afipia genospecies 3) were isolated from human wound and respiratory sources. All Afipia species are gram-negative, oxidase-positive, nonfermentative rods in the alpha-2 subgroup of the class Proteobacteria. They are motile by means of a single flagellum. They grow on buffered charcoal-yeast extract agar and nutrient broth, but rarely on MacConkey agar, at 25 and 30 degrees C. They are urease positive; but they are negative in reactions for hemolysis, indole production, H2S production (triple sugar iron agar), gelatin hydrolysis, esculin hydrolysis, and peptonization of litmus milk. They do not produce acid oxidatively from D-glucose, lactose, maltose, or sucrose. The major cell wall fatty acids are 11-methyloctadec-12-enoic (CBr19:1), cis-octadec-11-enoic (C18:1omega7c), and generally, 9,10-methylenehexadecanote and 11,12-methyleneoctadecanoate; and there are only trace amounts of hydroxy acids. The guanineplus-cytosine content is 61.5 to 69 mol%. A. felis is positive for nitrate reduction and is delayed positive for acid production from D-xylose, but it is catalase negative. A. clevelandensis is negative in all of these tests. A. broomeae is weakly positive for catalase production and acid production from D-xylose, but it is negative for nitrate reduction.

Bacterial Typing Techniques↗
PubMed1991

Campylobacter butzleri sp. nov. isolated from humans and animals with diarrheal illness.

Seventy-eight aerotolerant Campylobacter isolates were characterized phenotypically and by DNA hybridization (hydroxyapatite method at 50 and 65 degrees C). Two DNA relatedness groups were found. (i) Sixty-four strains belonged to aerotolerant Campylobacter DNA hybridization group 2. These organisms were isolated from humans, primarily with diarrheal illness, and animals on several continents. Strains were aerotolerant at 30 and 36 degrees C and catalase negative or weakly catalase positive, grew in media containing glycine and on MacConkey agar, were susceptible to nalidixic acid, and were resistant to cephalothin. The name Campylobacter butzleri sp. nov. is proposed for this group. (ii) DNA hybridization group 1 consisted of the type strain of Campylobacter cryaerophila and 13 additional strains isolated from 10 animals outside the United States and from three humans within the United States. This group was genetically diverse; five strains were closely related to the type strain of C. cryaerophila (DNA hybridization group 1A), and eight strains were more closely related to one another (DNA hybridization group 1B). Strains in DNA hybridization group 1B were phenotypically diverse, with two of eight strains resembling C. cryaerophila. The seven strains from DNA hybridization groups 1A and 1B which resembled C. cryaerophila and the C. cryaerophila type strain were aerotolerant only at 30 degrees C and catalase positive, did not grow in glycine or on MacConkey agar, were generally susceptible to nalidixic acid, and were resistant to cephalothin. The remaining six strains of DNA hybridization group 1B phenotypically resembled C. butzleri; however, they were generally catalase positive and susceptible to nalidixic acid and cephalothin. DNA hybridization group 1B is not designated as a separate species at this time since it cannot, with certainty, be separated genetically from C. cryaerophila or phenotypically from C. butzleri.

Animals↗
PubMed1991

Legionella fairfieldensis sp. nov. isolated from cooling tower waters in Australia.

Three Legionella-like organisms were isolated from water from the cooling towers of two Australian institutions. The strains grew on buffered charcoal-yeast extract (BCYE) agar but not on BCYE agar in the absence of L-cysteine. Gas-liquid chromatography profiles of the isolates were consistent with those for Legionella spp. They were serologically distinct from other legionellae in a slide agglutination test. DNA hybridization studies showed that the three isolates belong to a new species of Legionella, Legionella fairfieldensis (ATCC 49588).

Australia↗
PubMed1991

Legionella adelaidensis, a new species isolated from cooling tower water.

A Legionella-like organism (strain 1762-AUS-E) was isolated from a cooling tower of an air-conditioning system in Adelaide, South Australia, Australia. The isolate was presumptively identified as a Legionella strain by its growth requirement for L-cysteine and its cellular branched-chain fatty acids. Strain 1762-AUS-E was serologically distinct in the slide agglutination test with absorbed antisera. DNA hybridization confirmed that it is a new Legionella species for which the name Legionella adelaidensis is proposed.

Air Conditioning↗
PubMed1991

Molecular characterization and proposal of a neotype strain for Bartonella bacilliformis.

Bartonella bacilliformis, the etiologic agent of bartonellosis, was characterized biochemically and by DNA hybridization, guanine-plus-cytosine content, genome size, and 16S rRNA sequencing. DNAs from the two strains in our collection exhibited 97% relatedness in hydroxyapatite reactions done at 55 degrees C (optimal reassociation criterion) and 100% relatedness in reactions done at 70 degrees C (stringent reassociation criterion). There was no evidence of divergence within the related sequences. B. bacilliformis DNA showed no relatedness to the cat scratch disease bacillus or to a strain of a second species in the same genus as the cat scratch disease bacillus in hybridization reactions done at 65 degrees C. The guanine-plus-cytosine contents of DNAs from the two B. bacilliformis strains were 39 and 40 mol%. Time course reassociation, done by determining spectrophotometrically the time required for one-half of the denatured DNA to form duplexes, indicated that B. bacilliformis has a genome size of approximately 4 x 10(8). The 16S rRNA sequence analysis indicated that B. bacilliformis is in the alpha-2 subgroup of the purple bacteria, class Proteobacteria, and that its closest relatives are Rochalimaea quintana and Brucella abortus. Strain KC583 (= Herrer 020/F12,63 = ATCC 35685) is proposed as the type strain of B. bacilliformis.

Bartonella↗
PubMed1991

Trabulsiella guamensis, a new genus and species of the family Enterobacteriaceae that resembles Salmonella subgroups 4 and 5.

In 1985 the vernacular name Enteric Group 90 was coined for a small group of strains that had been referred to our laboratory as probable strains of Salmonella but did not agglutinate in Salmonella typing antisera. By DNA-DNA hybridization (hydroxyapatite method, 32P), seven strains of Enteric Group 90 were found to be closely related (98 to 100% at 60 degrees C and 94 to 100% at 75 degrees C) to the first strain received (0370-85). The relatedness of Enteric Group 90 to 62 strains of other species of the family Enterobacteriaceae was only 6 to 41%, with the highest values obtained with strains of Salmonella, Kluyvera, Shigella, Klebsiella, Enterobacter, and Citrobacter. We propose a new genus, Trabulsiella, with a single new species, Trabulsiella guamensis, for the highly related group of eight strains formerly known as Enteric Group 90. The type strain is designated ATCC 49490 (CDC 0370-85). T. guamensis strains grew well at 36 degrees C and had positive reactions in the following tests: methyl red, citrate utilization (Simmons) (38% positive at day 1, 88% positive at 2 days), H2S production, lysine decarboxylase, arginine dihydrolase (50% positive at 2 days, 100% positive at 7 days), ornithine decarboxylase, motility, growth in KCN medium, mucate fermentation, acetate utilization, nitrate reduction to nitrite, weak tyrosine hydrolysis (88% positive at 2 days, 100% positive at 7 days), and ONPG (o-nitrophenyl-beta-D-galactopyranoside) test. The strains fermented D-glucose with gas production and fermented L-arabinose, cellobiose, D-galactose, D-galacturonate, maltose, D-mannitol, D-mannose, L-rhamnose, D-sorbitol, trehalose, and D-xylose. T. guamensis strains had negative reactions in the following tests: indole production (13% positive), Voges-Proskauer, urea hydrolysis, phenylalanine deaminase, malonate utilization, lipase (corn oil), DNase, oxidase, pigment production, and acid production from adonitol, D-arabitol, dulcitol, erythritol, myo-inositol, melibiose, alpha-methyl-D-glucoside, raffinose, and sucrose. There were delayed positive reactions for gelatin liquefaction (22 degrees C), which was positive at 12 to 23 days, esculin hydrolysis (13% positive at day 1, 50% positive at 7 days), lactose fermentation (13% positive at 3 to 7 days, 100% positive at 8 to 10 days), glycerol fermentation (88% positive at 7 days), and salicin fermentation (13% positive at day 1, 88% positive at 7 days). All strains were susceptible by the disk diffusion method to colistin, nalidixic acid, gentamicin, streptomycin, kanamycin, chloramphenicol, and trimethoprim-sulfamethoxazole, and most strains were susceptible to sulfadiazine (75% susceptible), tetracycline (88%), and carbenicillin (75%). The strains were resistant to penicillin, cephalothin, and ampicillin. The strains were isolated from vacuum cleaner dust (five strains), soil (one strain), and human feces (two strains). Although T. guamensis can occur in human diarrheal stools, there is no evidence that it actually causes diarrhea. Its main interest to clinical microbiologists may be its possible misidentification as a strain Salmonella.

DNA, Bacterial↗
PubMed1991

Fractionated high dose rate versus low dose rate regimens for intracavitary brachytherapy of the cervix. I. General considerations based on radiobiology.

Intracavitary brachytherapy at low dose rate (LDR), often with the addition of external-beam radiotherapy, has long been considered the treatment of choice for carcinoma of the cervix, maximizing acute damage in the treatment volume, whilst minimizing late effects. In recent years, primarily for reasons of convenience and cost, there has been a move towards treatments involving a few fractions at high dose rate (HDR). Using data from cells of human origin cultured in vitro, we make estimates of the doses that, delivered in 2-12 HDR fractions, produce tumour control and early effects equivalent to intracavitary treatments at LDR. We also show that, for situations where the normal-tissue dose responsible for late effects is significantly smaller than the tumour dose, HDR schemes may be devised which, while yielding early killing comparable with that of LDR, should not result in worse late effects. We suggest that this scenario probably applies to treatment of carcinoma of the cervix.

Brachytherapy↗
PubMed1991

Accelerated heavy particles and the lens. VI. RBE studies at low doses.

We report on the prevalence, hazard, and relative biological effectiveness (RBE) for various stages of lens opacification in rats induced by very low doses of fast argon ions of LET 88 keV/microns, compared to those for X rays. Doses of argon ions from 0.01 to 0.25 Gy were used and RBEs of these ions relative to X rays estimated using a nonparametric technique. At the end of the follow-up period, which encompasses a significant fraction of the animals' lifetime, 90% confidence intervals for the RBE of the argon ions relative to X rays were 4-8 at 0.25 Gy, 10-40 at 0.05 Gy, and 50-100 at 0.01 Gy. Our results are consistent with the point-estimate neutron RBEs in Japanese A-bomb survivors, though broad confidence bounds are present in the Japanese results. If a reasonable extrapolation to higher doses is used, our results are also consistent with data reported earlier at higher doses for argon-ion cataractogenesis in rats, mice, and rabbits. We conclude from these results that at very low doses the RBE for cataractogenesis from HZE particles in space is considerably more than 20, and use of a quality factor of at least 50 would be prudent.

Animals↗
PubMed1991

Neoplastic transformation and the inverse dose-rate effect for neutrons.

Considerable evidence has recently accumulated, both in vivo and in vitro, to suggest that neutrons at low dose rates, or in multiple fractions, have an enhanced effectiveness for inducing neoplastic transformation. A consistent pattern has emerged as to the dependence of the effect on dose, dose rate, and radiation type. A consistent model of the phenomenon as a function of dose, dose rate, and radiation type is presented. The approach, first suggested by Rossi, is that cells are extra sensitive in part of their cycle. Then an acute exposure of cycling cells to high-LET radiation results in some fraction of the sensitive cells receiving large depositions of energy--greater than required for the effect. If the exposure is protracted, a larger proportion of sensitive cells will be exposed, but to smaller numbers of energy depositions--still enough, however, to produce the effect. The model produces results consistent with all available data on enhancement of neoplastic transformation in the C3H 10T1/2 system by protraction or fractionation at medium or high LET. Implications for radiation protection and the radon problem are discussed.

Animals↗
PubMed1991

Hiroshima-like neutrons from A-bomb replica: physical basis for their use in biological experiments.

The lineal energy distribution and several other dosimetric parameters were measured for the neutrons emitted from a replica of the Hiroshima bomb to determine their usefulness in biological experiments designed to estimate the effectiveness of actual Hiroshima neutrons. The "Little-Boy" replica (LBR) was constructed at the Los Alamos National Laboratory in support of the recent atomic-bomb dose reevaluation and was made of identical materials and had nearly identical dimensions and geometry as the Hiroshima bomb. However, the LBR was operated as a steady-state nuclear reactor, which permitted measurements under controlled conditions. Detailed dosimetric measurements and calculations were made at distances of up to 2.1 m from the center of the LBR uranium core. At these distances, the in-air kerma was approximately 97% from neutrons and kerma rates were shown to be particularly useful for biological experiments (up to approximately 7 Gy/h was possible). Quantitative intercomparisons of neutron energy spectra, lineal energy distributions, and measured cytogenetic results for several fission-neutron sources indicate that Hiroshima and LBR neutrons should be of similar biological effectiveness. Based on these evaluations, and cytogenetic results for LBR neutrons reported in a companion paper (this issue), it is estimated that Hiroshima neutrons were 20 to 30% more effective than the fission neutrons commonly used in radiobiology.

Neutrons↗
PubMed1990

The relative biological effectiveness of photon radiation from encapsulated iodine-125, assessed in cells of human origin: I. Normal diploid fibroblasts.

The relative biological effectiveness (RBE) of photon radiation from encapsulated Iodine-125 "seed" sources has not previously been investigated in human cells. The RBE of 125I photons relative to 137Cs gamma rays was examined in normal diploid human fibroblasts derived from lung and skin. The cells were irradiated in plateau phase using a specially designed incubator-irradiator which permitted simultaneous 125I and 137Cs irradiation. The cells were irradiated at various dose rates ranging from 7 to 70 cGy/hr. Dosimetry was performed using Monte Carlo computer calculations to simulate the 125I irradiations and the exposure-standardization measurements made by the U.S. National Bureau of Standards which are the basis for the specified strengths of 125I seeds. Simulation of the exposure standardization measurements revealed systematic errors due to the unrecognized presence of low-energy fluorescence X rays. The specified activity of the type of seeds used for this study (high-activity, no radiographic marker) was found to be too high by more than 10%. The RBE of 125I assessed with both lung fibroblast lines was found to be 1.2 and was 1.3 for the skin fibroblasts. The RBE did not change over the range of dose rates tested. In fact, for both 125I and 137Cs, the dose response curves did not change with dose rate over the range tested, implying full repair of sublethal damage at dose rates below 70 cGy/hr in these non-dividing cells.

Brachytherapy↗
PubMed1990

Identification of the bacterium associated with haemorrhagic septicaemia in rainbow trout as Hafnia alvei.

An unidentified bacterium responsible for epizootic haemorrhagic septicaemic disease in rainbow trout was recently described. This organism exhibited some antigenic similarity to Brucella abortus and to Yersinia ruckeri and was presumed to belong to the family Enterobacteriaceae. Further biochemical characterization and DNA relatedness studies showed that pathogenic fish strains are Hafnia alvei.

Animals↗
PubMed1990

Legionella sainthelensi serogroup 2 isolated from patients with pneumonia.

Three Legionella-like organisms isolated from patients with pneumonia are shown to belong to the species Legionella sainthelensi by DNA hybridization studies and to a new serogroup, serogroup 2, by serological studies (ATCC 49322). L. sainthelensi serogroup 2 and L. santicrucis are indistinguishable by slide agglutination, but are separable on the basis of their cell wall fatty acid profiles.

Agglutination Tests↗
PubMed1990

Confidence limits for low induced frequencies of oncogenic transformation in the presence of a background.

The problem is addressed of assessing realistic confidence limits for oncogenic transformation rates when the incidence of transformation is small, and there is a background present. It is shown that the commonly used approximations for assessing the confidence interval on the radiation-induced transformation rate (t1) and the control rate (t2) are inadequate when only a small number of transformants are observed. Accurate techniques are described for these cases for the estimation of confidence limits of t1, t2 and also t1-t2.

Cell Transformation, Neoplastic↗
PubMed1990

The inverse dose-rate effect for oncogenic transformation by neutrons and charged particles: a plausible interpretation consistent with published data.

The enhancement of oncogenic transformation in the C3H10T1/2 system by protraction of a high-LET irradiation has been widely reported. Prima facie, the results are inconsistent in that some but not all experiments have shown an enhancement. That the reported data follow a clear pattern is shown, and a model whose predictions are quantitatively consistent with these trends is discussed. The model, developed from that originally suggested by Rossi and Kellerer (1986), postulates that cells are especially sensitive to radiation during some period of their cycle. A sensitive period of about 1 h is shown to yield predictions consistent with all available data. If the suggested model is realistic and applicable to human cells in vivo, little enhancement would be expected for high-LET radiations such as from radon daughters or HZE cosmic rays, though an effect might be expected from trapped protons on astronauts in earth orbit. For fission neutrons a time-dependent factor of N = 2 in the formula for dose equivalent (H = DQN) might be appropriate for very low dose rates, if a quality factor Q = 10 were applied. If Q was taken as 20, then a value of N = 1 would probably be adequate.

Animals↗
PubMed1990

Erwinia persicinus, a new species isolated from plants.

Five strains of a gram-negative, oxidase-negative, facultatively anaerobic, fermentative, motile, rod-shaped bacterium with the general characteristics of the family Enterobacteriaceae were isolated from tomatoes (three strains), a banana, and a cucumber. All of the strains produced a water-soluble pink pigment. As determined by DNA hybridization (hydroxyapatite method) these five strains were 85 to 100% related in 60 and 75 degrees C reactions, and related sequences exhibited 1% or less base sequence divergence, indicating that the organisms are members of a single species. These bacteria were most closely related to Erwinia rhapontici (68 to 72% at 60 degrees C, 42 to 44% at 75 degrees C, 10.5% divergence) and to hybridization group VIII in the Enterobacter agglomerans (Pantoea agglomerans, Erwinia herbicola) complex (64% at 60 degrees C, 32% at 75 degrees C, 14.5% divergence). Phenotypic differentiation from Erwinia rhapontici, which also produces a water-soluble pink pigment, is based on negative reactions by the new species in tests for methyl red, N-acetylglucosamine, DL-tartrate assimilation, and acid production from amygdalin, dulcitol, D-fucose, beta-gentiobiose, alpha-methyl-D-glucoside, glycerol, D-lyxose, melezitose, D-turanose, xylitol, and D-xylose and a positive reaction for acetoin (Voges-Proskauer test). On the basis of these data, the name Erwinia persicinus is proposed for the new organism. The type strain is strain HK 204 (= AJ 2716 = CDC 9108-82 = IAM 12843 = JCM 3704 = ATCC 35998).

Base Composition↗