bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of Legionella pneumophila, L. micdadei, L. bozemanii, and L. dumoffii by transmission electron microscopy
Authors: Hébert G A , Callaway C S , Ewing E P
Published: January 2020

Clinical isolates of Legionella pneumophila, L. micdadei, L. bozemanii, and L. dumoffii were grown on charcoal-yeast extract agar from a living-medium inoculum and prepared for transmission electron microscopy by three different methods. Cells of all four Legionella species possessed cytoplasmic vacuoles, a gram-negative type of cell envelope with a dense peptidoglycan-like layer, a ruthenium red-positive polysaccharide capsule, and a single subpolar flagellum. The dense polysaccharide capsule seen on cells of L. micdadei was separated from the outer membrane by an extra layer of electron-lucent material that was not present on cells of the other species examined.
Analysis of Campylobacter jejuni antigens with monoclonal antibodies
Authors: Kosunen T U , Bång B E , Hurme M
Published: January 2020

To develop monoclonal reagents for antigenic analysis and serotyping of Campylobacter spp., hybridoma cell lines were produced by fusion of mouse myeloma cells and spleen cells from mice immunized with Formalin-treated Campylobacter jejuni organisms. An enzyme immunoassay was used for preliminary screening of the cell culture supernatants and ascites. Twenty-nine clones which reacted with the immunogen were obtained. Seven of these clones were positive in passive hemagglutination tests with sheep erythrocytes coated with boiled saline extract of whole bacteria; four of these reacted with the purified polysaccharide preparation and with the autoclaved saline extract, but not with lipopolysaccharide prepared from the immunogen strain. Two of the antipolysaccharide clones agglutinated live bacteria in slide tests. Four additional clones gave positive slide agglutination tests with live bacteria, but in tube testing no clones agglutinated Formalin-treated bacteria. No cross-reactions with unrelated bacteria were seen, but several clones reacted in the enzyme immunoassay with many of the 24 Campylobacter strains studied. The clone which gave the highest mean enzyme immunoassay values with Campylobacter coli and C. jejuni strains also reacted with Campylobacter fetus subsp. veneralis and C. fetus subsp. fetus strains. This clone also gave the highest enzyme immunoassay value with an acid glycine extract of the immunogen, which indicates the presence of common antigens in the extract. The results suggest that monoclonal antibodies may be used to devise serotyping schemes for Campylobacter spp.
Serotyping and biotyping of Campylobacter jejuni and Campylobacter coli from sporadic cases and outbreaks in Norway
Authors: Kapperud G , Lassen J , Lauwers S , Rosef O
Published: January 2020

Of 172 thermophilic campylobacters isolated from human cases of gastroenteritis in Norway, 149 (86.6%) were classified as Campylobacter jejuni, whereas 23 isolates (13.4%) belonged to Campylobacter coli. C. jejuni biotype 1 comprised 66.3% and C. jejuni biotype 2 comprised 20.3% of the total number. Using 50 unabsorbed antisera, we were able to serotype 109 (80.1%) of 136 campylobacters on the basis of heat-stable antigens identified by means of passive hemagglutination. The typable strains fell into 36 different serotypes. A large proportion of the strains were isolated from travellers returning from abroad, a state of affairs which may have influenced the serotype and biotype distribution. Two family outbreaks were found to be caused by a bio-serotype common to all diseased members of the particular families. A third family outbreak and an outbreak among employees at a poultry processing plant each involved two distinct strains.
Wound infections caused by Vibrio vulnificus, a marine vibrio, in inland areas of the United States
Authors: Tacket C O , Barrett T J , Mann J M , Roberts M A , Blake P A
Published: January 2020

Vibrio vulnificus is a halophilic marine vibrio which may produce infection in wounds exposed to seawater or raw shellfish. The Centers for Disease Control has received two isolates from wounds exposed to inland waters, a New Mexico creek and an Oklahoma reservoir. Halophilic organisms were recovered from both the creek and the reservoir, and the water in both sites was found to be brackish. Both clinical isolates of V. vulnificus grew in salt concentrations as low as those found in the creek and reservoir. These cases illustrate the potential for pathogenic halophilic Vibrio species to live in brackish inland waters and produce infections in patients living in inland areas of the United States.
Large-scale serological screening for cytomegalovirus antibodies in homosexual males by enzyme-linked immunosorbent assay
Authors: Dylewski J S , Rasmussen L , Mills J , Merigan T C
Published: January 2020

We compared an enzyme-linked immunosorbent assay (ELISA) with complement fixation and radioimmunoassay in determining the presence of immunoglobulin antibodies to cytomegalovirus. Of an initial 93 serum samples tested, the correlation between ELISA and radioimmunoassay was 98.9% and that between ELISA and complement fixation was 96.1%. ELISA was used to screen 1,123 homosexual men in San Francisco. Of 479 men attending a homosexual health fair, 35 (7%) lacked cytomegalovirus antibodies by ELISA. Only 15 (2%) of 644 homosexual men attending a municipal sexually transmitted disease clinic were found to be seronegative. All but one of the seronegatives detected by ELISA were also seronegative by radioimmunoassay and complement fixation. We conclude that ELISA can be used to reliably perform large-scale screening for the presence of immunoglobulin G antibodies to cytomegalovirus.
Isolation of Corynebacterium group JK from clinical specimens with a semiselective medium
Authors: Wichmann S , Wirsing von Koenig C H , Becker-Boost E , Finger H
Published: January 2020

A semiselective medium for the detection of multiresistant lipophilic corynebacteria is described. The medium consisted of tryptose agar, supplemented with Tween 80, lecithin, histidine, glycerol, sodium thiosulfate, fosfomycin, ticarcillin, and 5-fluorocytosine. The medium was tentatively called lecithin-Tween medium (LT medium). It promoted mainly the growth of Corynebacterium group JK, which has recently been identified as a cause of serious infection in immunocompromised patients. The application of LT medium to 6,859 routine clinical specimens increased the percentage of Corynebacterium group JK isolation from 0.1 to 1.0%. Although a total of 72 isolates were found in 65 patients, on the basis of clinical criteria only 2 patients were regarded as having an infection with these bacteria. Consequently, Corynebacterium group JK infection can only be diagnosed through a combination of clinical and microbiological findings. In high-risk areas, however, the use of LT medium for surveillance may facilitate the early detection of these potentially dangerous organisms.
Evaluation of the API 20 Strep system for species identification of streptococci isolated from bovine mastitis
Authors: Poutrel B , Ryniewicz H Z
Published: January 2020

A new commercial system (API 20 Strep) for the species identification of streptococci associated with bovine mastitis was compared with the conventional biochemical methods. A total of 84 strains, including Streptococcus agalactiae (13), S. dysgalactiae (16), S. uberis (24), S. faecalis (12), S. faecium (5), and S. bovis (14) were tested. Using profile index and table data issued by the manufacturer, we identified 71.4% of strains by the API 20 Strep system. Our results indicate that improvement of the identification key is needed for accurate identification of streptococci isolated from bovine mastitis.
Isolation of Neisseria gonorrhoeae on selective and nonselective media in a sexually transmitted disease clinic
Authors: Bonin P , Tanino T T , Handsfield H H
Published: January 2020

To assess the practical significance of reported increases in the prevalence of vancomycin-susceptible strains of Neisseria gonorrhoeae on isolation of this organism, antibiotic-free chocolate agar (CA), modified Thayer-Martin medium (MTM), and a vancomycin-free selective medium (VFSM) were compared in a sexually transmitted disease clinic. Among 326 cervical gonococcal infections detected in a comparison of CA with MTM, 92.0% were detected on CA, compared with 98.2% on MTM (P less than 0.001). Similarly, among 306 cervical infections detected in a comparison of MTM and VFSM, 95.8% of infections were detected with VFSM, compared with 98.4% for MTM (P = 0.10). For 1,632 urethral infections in men, all three media were equivalent, with none detecting fewer than 98% of the infections. Compared with a single inoculation, dual inoculation of MTM increased the diagnostic yield by 1.5% for 206 urethral infections and 2.4% for 83 cervical infections. In our clinic population, MTM is superior to CA or VFSM for the diagnosis of genital gonococcal infections, especially in women. The increased yield that accrued from inoculation of both MTM and either of the other media was not sufficiently high to warrant routine use of this practice in our clinic.
Microvolume, kinetic-dependent enzyme-linked immunosorbent assay for amoeba antibodies
Authors: Mathews H M , Walls K W , Huong A Y
Published: January 2020

We describe a microvolume enzyme-linked immunosorbent assay based on enzyme rate kinetics. Antigens from Entamoeba histolytica were adsorbed in wells of disposable polystyrene strips containing 12 flat-bottom wells. After exposure to the serum of a patient and peroxidase-labeled anti-human immunoglobulin G, the rate of color change in specific substrate was determined by eight sequential readings of individual wells over a 2-min period with a microcomputer-controlled model MR-600 automated plate reader. The changes in absorbance readings were converted to slope values for each well by the microcomputer. Thus, 12 samples were read, and results were printed in ca. 3.5 min. Assay conditions are described and data are presented to show that this assay is quantitative for antibody and antigen concentration with a single-tube (well) dilution.
Rapid detection of bacteriuria by laser nephelometry
Authors: Richet H , Bayardelle P , Lemarie J C
Published: January 2020

A total of 1,002 urine specimens were evaluated by laser nephelometry. This technique was compared with both colony counts, done with a calibrated loop, and serial dilutions. For urine specimens containing between 10(4) and 10(5) bacteria per ml, laser nephelometry detected 75.4% of those detected by colony count and 65.6% of those detected by serial dilution. For specimens where the concentration of bacteria was greater than 10(5) per ml, laser nephelometry detected 95.8 and 92.4% of those detected by colony count and serial dilution, respectively. The mean detection time for bacteriuria varied from 1.57 h for more than 10(5) bacteria per ml to 4.47 h for more than 10(4) bacteria per ml. To determine the number of bacteria according to the voltage growth curve, the passage time at 3 V was used as an index. The mean passage time at 3 V decreased from 5.18 h for fewer than 10(4) bacteria per ml to 1.42 h for more than 10(6) bacteria per ml. The mean passage time at 3 V differed significantly for different concentrations of bacteria. Thus, this index allowed us to predict the number of bacteria in the urine specimens. Laser nephelometry has been used for many years for the immunological determination of proteins; it can now also be considered a tool for rapid screening in bacteriology.
Rapid identification of antibiotic-resistant corynebacteria with the API 20S system
Authors: Kelly M C , Smith I D , Anstey R J , Thornley J H , Rennie R P
Published: January 2020

The API 20S system (Analytab Products, Plainview, N.Y.) was evaluated for the rapid identification of multiply antibiotic-resistant aerobic diphtheroids. Sixty-eight clinical isolates of multiply resistant Centers for Disease Control group JK and group D2 corynebacteria had API 20S profiles which were clearly different from those of a number of strains of other Corynebacterium species which were tested. The API 20S system allowed more rapid identification of antibiotic-resistant diphtheroids than conventional biochemical tests. Its use for corynebacteria other than group JK and group D2 is not recommended at this time.
Five-hour novobiocin test for differentiation of coagulase-negative staphylococci
Authors: Harrington B J , Gaydos J M
Published: January 2020

A 5-h broth disk test, read visually for growth or no growth to determine resistance of coagulase-negative staphylococci to 1.6 micrograms of novobiocin per ml, was evaluated as a rapid test for the presumptive identification of Staphylococcus saprophyticus. The correlation with an overnight disk diffusion test was 100%.
Effect of storage of the du Pont lysis-centrifugation system on recovery of bacteria and fungi in a prospective clinical trial
Authors: Stockman L , Roberts G D , Ilstrup D M
Published: January 2020

A commercially available lysis-centrifugation system was compared with a conventional biphasic brain heart infusion medium in a prospective clinical study of 5,125 fungal blood cultures. Recovery rates were compared between two time periods to assess the effect of 25 degrees C storage before processing by the lysis-centrifugation system. The lysis-centrifugation tubes processed within 9 h showed a significantly higher yield (3.4 versus 1.49%) for yeasts (Candida glabrata), filamentous fungi (Histoplasma capsulatum), and bacteria (8.84 versus 7.34%) (Klebsiella pneumoniae and Serratia marcescens) than did those processed after 9 h.
Characterization of Pseudomonas cepacia isolates from patients with cystic fibrosis
Authors: McKevitt A I , Woods D E
Published: January 2020

Pseudomonas cepacia infections which follow a fulminant course and which include septicemia are being reported with increasing frequency from cystic fibrosis patients. Forty-eight P. cepacia isolates from cystic fibrosis patients were screened for production of potential virulence factors. A majority of strains tested produced protease and lipase. Eleven strains harbored plasmids of approximate molecular weights in the range 50 X 10(6) to 100 X 10(6). Twenty-two strains produced a smooth lipopolysaccharide. Studies are presently under way to determine the role of these potential virulence factors in the pathogenesis of P. cepacia disease.
Analysis of fatty acids of the genus Rochalimaea by electron capture gas chromatography: detection of nonanoic acid
Authors: Westfall H N , Edman D C , Weiss E
Published: January 2020

The fatty acid compositions of Rochalimaea quintana, strains Fuller and Guadalupe, and R. vinsonii, the Canadian vole agent, were determined in an effort to further characterize these bacteria. The cells were saponified with 5% NaOH in 50% methanol and acidified to pH 2. The methanolysates were extracted with chloroform, derivatized with 2,2,2-trichloroethanol, and analyzed using a Hewlett-Packard gas chromatograph equipped with a frequency pulse-modulated electron capture detector and a 3% OV-101 packed-glass column. The fatty acid profiles of the three Rochalimaea strains were similar, with octadecenoic acid (C18:1) the most abundant, followed by octadecanoic (C18:0) and hexadecanoic (C16:0) acids. Moderate to trace amounts of other acids were also present. Unexpectedly, well-defined peaks of nonanoic acid (C9) were found consistently. A portion of this acid, but not all, was extractable with chloroform. Since C9 is not reported as a usual component of bacteria and most analyses do not include a search for this fatty acid, this study was extended to three strains of Legionella and one of Campylobacter. Comparable results were obtained. Since these bacteria were grown in complex media which contain some C9, it is possible that the medium is the source of bacterial C9. Whether this compound can be synthesized by the bacteria remains to be investigated.
Capillary gas chromatographic analysis of carbohydrates of Legionella pneumophila and other members of the family Legionellaceae
Authors: Fox A , Lau P Y , Brown A , Morgan S L , Zhu Z T , Lema M , Walla M D
Published: January 2020

Legionella pneumophila, the causative agent of Legionnaires disease, and related organisms have previously been characterized primarily by conventional bacteriological methods, DNA-DNA hybridization, antigenic analysis, and fatty acid analysis. By capillary gas chromatographic analysis for carbohydrates, we have shown that muramic acid and glucosamine, characteristic markers of bacterial cell walls, were present in samples of L. pneumophila and a group of legionella-like organisms. Some bacterial samples contained two unusual isomeric aminodideoxyhexoses (X1 and X2). L. pneumophila was characterized by the absence of fucose and the presence of the peak X1. Tatlockia micdadei (Legionella micdadei) was distinguishable by the presence of large amounts of rhamnose and fucose and by the absence of X1 and X2. Fluoribacter strains were much more variable in their carbohydrate composition. These data suggest that, in addition to other reported techniques, carbohydrate profiling by capillary gas chromatography can be a valuable diagnostic method in reference microbiology laboratories for differentiating members of the family Legionellaceae.
Validity of an enzyme immunoassay for detection of Neisseria gonorrhoeae antigens
Authors: Papasian C J , Bartholomew W R , Amsterdam D
Published: January 2020

An enzyme immunoassay (EIA; Gonozyme, Abbott Laboratories) for the antigenic detection of Neisseria gonorrhoeae in endocervical or urethral specimens was evaluated. EIA results were compared with results of conventional culture tests for N. gonorrhoeae. Specimens from 208 males (113 culture positive) and 252 females (72 culture positive) were tested. The sensitivity and specificity of EIA for specimens from males were 97.3 and 95.8%, respectively. The sensitivity and specificity of EIA for specimens from females were 79.2 and 87.2%, respectively.
Etiological diagnosis of influenza A virus by enzymatic radioimmunoassay
Authors: Coonrod J D , Betts R F , Linnemann C C , Hsu L C
Published: January 2020

An enzymatic radioimmunoassay for influenza A virus was developed by using polystyrene beads coated with rabbit immunoglobulin G to capture viral hemagglutinins (H1 and H3). Captured hemagglutinin was detected with goat immunoglobulin G followed by affinity-purified rabbit anti-goat immunoglobulin G labeled with alkaline phosphatase. [3H]AMP was added to quantify alkaline phosphatase activity, and free [3H]adenosine was measured with a scintillation counter. The assay detected as little as 0.1 ng of purified hemagglutinin. It was specific for hemagglutinin subtype and, depending on the source of the goat immunoglobulin G used, detected either H1 or H3. There was no reaction with neuraminidase or core antigens of influenza strain WSN-33. The clinical efficacy of the assay was evaluated with sequential nasal washes from 33 patients with naturally acquired H1N1 influenza. In the first 3 days of infection, the assay was consistently less sensitive than the viral culture, although detectable antigen persisted in secretions longer than did the infectious virus. Testing of multiple samples greatly increased the number of individuals in whom an etiological diagnosis could be made by immunoassay (81% of patients were positive for viral antigens at some point in their illness), and such testing was necessary to achieve the sensitivity of a single culture. Mean antigen levels were highest in nasal washes with the highest titers of infectious virus.
Enzyme-linked immunosorbent assay for evaluation of immunity to measles virus
Authors: Weigle K A , Murphy M D , Brunell P A
Published: January 2020

An enzyme-linked immunosorbent assay for the determination of immunity to measles virus was developed and standardized; it was compared to the hemagglutination inhibition and plaque reduction neutralization methods for sensitivity and specificity. The conditions of the enzyme-linked immunosorbent assay were adjusted such that groups of susceptible and immune individuals were clearly separable on the basis of the reactivity of a single (1:100) dilution of their sera to viral and control antigens. The range of values corresponding to susceptibility and immunity was defined by using the distribution of values observed from testing sera obtained from susceptible and immune control groups. The enzyme-linked immunosorbent assay was then applied in a study of measles vaccinees and found to be more sensitive than the hemagglutination inhibition method and equal in sensitivity to the plaque reduction neutralization method. The three methods were equal in specificity. Thus, the measles virus enzyme-linked immunosorbent assay is a rapid, reproducible, sensitive, and specific method for screening for the presence of measles antibody.
Enzyme-linked immunosorbent assay for detection of Staphylococcus aureus alpha-toxin
Authors: Surujballi O P , Fackrell H B
Published: January 2020

A sandwich enzyme-linked immunosorbent assay was developed for measuring Staphylococcus aureus alpha-toxin. This assay was 500 to 1,000 times more sensitive than the commonly used hemolytic titration assay and was less variable. The binding of alpha-toxin to the adsorbed antibody was most effective after an overnight incubation at 27 degrees C. The toxin was detectable even at a log2 17 dilution of an S. aureus culture supernatant.
Isolation and identification of yeasts and yeastlike organisms from clinical veterinary sources
Authors: Chengappa M M , Maddux R L , Greer S C , Pincus D H , Geist L L
Published: January 2020

A total of 229 isolates of yeasts and yeastlike organisms recovered from a variety of clinical specimens were identified by using the API 20C microsystem in conjunction with morphological characteristics and urea hydrolysis. Of the 229, 218 (95.1%) were from bovine, porcine, canine, and equine species and the remaining 11 (4.9%) were from feline and avian species. The gastrointestinal and reproductive tracts were the major sources of yeasts and yeastlike organisms, representing 60 (26.2%) and 28 (12.2%) isolates, respectively.
Retrospective examination of lung tissue specimens for the presence of Legionella organisms: comparison of an indirect fluorescent-antibody system with direct fluorescent-antibody testing
Authors: Brown S L , Bibb W F , McKinney R M
Published: January 2020

Although direct fluorescent-antibody (DFA) testing has been used successfully for a number of years to detect legionellae in clinical specimens, the number of known species and serogroups of Legionella has now increased to such an extent that the performance of DFA testing for all serological variants is impractical. Lung homogenates that were submitted to the Centers for Disease Control, Atlanta, Ga., from patients with suspected legionellosis, from November 1977 through May 1982, were originally screened by DFA testing. In our study 498 of these lung homogenates were screened by indirect fluorescent-antibody (IFA) testing, using a panvalent antiserum pool containing antibodies to 25 serological variants of Legionella spp. Fluorescein isothiocyanate-labeled goat anti-rabbit immunoglobulin was used as the second antibody of the sandwich system. For positive homogenates, i.e., those containing Legionella organisms, species and serogroup identification was made by IFA staining with polyvalent serum pools and then with monovalent antiserum. Of the 498 homogenates screened, 39 (7.8%) were positive by IFA testing. Four (0.8% of total; 10.3% of positive homogenates) of these had previously been negative by DFA testing, but subsequent testing showed that they contained Legionella organisms for which DFA reagents were not available at the initial screening. All specimens that were positive by DFA testing were also positive by IFA testing. IFA testing with polyvalent antisera is a simple, efficient method which is at least as sensitive as DFA testing and which can be used by clinical laboratories to cope with the increasing number of known serological variants of Legionella spp.
Differentiation of Alcaligenes-like bacteria of avian origin and comparison with Alcaligenes spp. reference strains
Authors: Berkhoff H A , Riddle G D
Published: January 2020

Although standard biochemical tests used for the identification of Alcaligenes spp. revealed only minor differences, the oxidative low-peptone technique clearly differentiated between Alcaligenes-like bacteria of avian origin and Alcaligenes spp. reference strains. Based on their colonial morphology, biochemical profiles, and hemagglutination, the Alcaligenes-like bacteria of avian origin were further divided into two subgroups, C1-T1 and C2-T2. Colonies of subgroup C1-T1 were nondescript, round, raised, glistening, translucent, greyish, and about 2 mm in diameter. Colonies of subgroup C2-T2 were off-white, flat, dry and wrinkled, generally round, and resembled tiny lily pads. Biochemical profiles by the oxidative low-peptone method showed the C1-T1 subgroup alkalinizing only three substrates (citrate, acetate, and succinate), whereas the C2-T2 subgroup alkalinized eight substrates (citrate, acetate, butyrate, itaconate, malonate, saccharate, succinate, and M-tartrate). Subgroup C1-T1 agglutinated human, chicken, and turkey erythrocytes, whereas subgroup C2-T2 did not. The recognition of these two subgroups within the Alcaligenes-like bacteria of avian origin is important, since it may explain the differences seen in pathogenicity among isolates.
Prevalence of heat-stable II enterotoxigenic Escherichia coli in pigs, water, and people at farms in Thailand as determined by DNA hybridization
Authors: Echeverria P , Seriwatana J , Patamaroj U , Moseley S L , McFarland A , Chityothin O , Chaicumpa W
Published: January 2020

The DNA hybridization assay employing a 460-base-pair fragment of DNA encoding for the methanol-insoluble form of heat-stable toxin (ST-II) was used to determine the prevalence of ST-II enterotoxigenic Escherichia coli (ETEC) in pigs, people, and water at 57 farms in Sri Racha, Thailand. ST-II ETEC was found in 62 (3%) of 2,110 suckling, 181 (32%) of 560 weaned, and 4 (1%) of 457 adult pigs examined. Of 62 suckling pigs with ST-II ETEC infections 21% had diarrhea, but none of 185 infected older pigs had diarrhea. ST-II ETEC was found more frequently in suckling pigs with diarrhea than without diarrhea (13 of 146 versus 49 of 1,964) (P less than 0.001). ST-II ETEC was detected in water collected from 3 of 57 clay jars containing water used to bathe at three pig farms, in 1 jar used to bathe immediately after working in the barn, and from one farmer who did not have a recent history of diarrhea. Evidence of this organism was not found in 245 other individuals living on the pig farms or in 220 inhabitants and 114 water specimens collected at tapioca farms nearby. In Thailand ST-II ETEC was found in suckling pigs with diarrhea but was infrequently found in humans.
Antiviral effects of bovine interferons on bovine respiratory tract viruses
Authors: Fulton R W , Downing M M , Cummins J M
Published: January 2020

The antiviral effects of bovine interferons on the replication of bovine respiratory tract viruses were studied. Bovine turbinate monolayer cultures were treated with bovine interferons and challenged with several bovine herpesvirus 1 strains, bovine viral diarrhea virus, parainfluenza type 3 virus, goat respiratory syncytial virus, bovine respiratory syncytial virus, bovine adenovirus type 7, or vesicular stomatitis virus. Treatment with bovine interferons reduced viral yield for each of these viruses as compared with that of control cultures.
Monoclonal antibody enzyme-linked immunosorbent assay for identification of K99-positive Escherichia coli isolates from calves
Authors: Mills K W , Tietze K L
Published: January 2020

For Escherichia coli to produce diarrhea in animals it must possess the ability to attach to the epithelial cells of the intestine and to produce enterotoxins. Tests developed to differentiate pathogenic from nonpathogenic E. coli have relied on detection of adherence structures called pili or detection of the toxins. We utilized a monoclonal antibody to K99 pili in an enzyme-linked immunosorbent assay to detect the presence of K99 pili in E. coli isolated from calves. Twenty-three E. coli isolates that were known to be stable toxin positive were all shown to produce K99 pili. A 100% correlation also was shown between the presence of K99 antigen and production of stable toxin by E. coli isolates. Of the 251 isolates, 245 were negative by K99 enzyme-linked immunosorbent assay and stable toxin assay. The other six were positive on both tests. The enzyme-linked immunosorbent assay also was shown to be specific for K99 pili by antibody-blocking assays. The number of E. coli necessary for detecting K99 pili by enzyme-linked immunosorbent assay was determined to be 3.5 X 10(5) bacteria per ml.
Group B streptococcal Ibc protein antigen: distribution of two determinants in wild-type strains of common serotypes
Authors: Johnson D R , Ferrieri P
Published: January 2020

Studies were carried out on the distribution of the Ibc protein antigenic marker in wild-type strains of group B streptococci of diverse serotypes isolated from epidemiological studies. Rabbits were immunized with group B streptococcal strain H36B, a prototype Ib strain, to produce antibody to the Ibc protein antigens. One antiserum (no. 970) contained antibody only against the trypsin-sensitive (TS) portion of the Ibc antigen. A second antiserum (no. 973), however, contained antibody to both the TS and the trypsin-resistant (TR) determinants or components of the antigen. A total of 785 wild-type strains of group B streptococci were serotyped by using antiserum 973 as well as antisera to the polysaccharide types Ia, Ib, II, III, and IV. Remarkably, 59% of all the strains tested (462 of 785) reacted positively with the Ibc antiserum, although not all carried both components of the Ibc antigen. Of the 99 Ib strains examined, 84% carried both TS and TR components. In contrast, 96% of the 202 Ic strains carried only the TR component of the Ibc antigen. Antiserum 970 failed to identify these strains. Routine typing with an antiserum which contains antibodies to only one portion of the Ibc antigen could result in significant serotype misidentification. Differentiation of group B streptococcal strains by the presence or absence of individual TS or TR components of the Ibc antigen could prove to be a useful additional epidemiological and serological marker. It is noteworthy that wild-type Ic strains carry, ordinarily, only the TR component, in contrast to the prototype Ic strain, which possesses the complete Ibc protein antigen. The possible contribution of the Ibc antigen to group B streptococcal virulence is of interest and requires further study.
Distribution and relationship to serotype of Haemophilus influenzae biotypes isolated from upper respiratory tracts of children and adults in Papua New Guinea
Authors: Gratten M , Lupiwa T , Montgomery J , Gerega G
Published: January 2020

The relationship between serotypes and biotypes of 505 carriage strains of Haemophilus influenzae isolated from the upper respiratory tracts of well children, children with pneumonia, and healthy adults was studied. All except serotype c were significantly associated with one or two specific biotypes (P less than 0.001). No encapsulated organisms belonging to biotypes V, VI, or VII were encountered. No significant difference in the interaction of biotypes and serotypes isolated from well and sick children was present. Both encapsulated and nonserotypable biotype I H. influenzae strains were commonly carried in the upper respiratory tracts of healthy Melanesian children. The distribution of nonserotypable H. influenzae strains occurred throughout all biotypes, and the frequency of nonencapsulated biotype III and IV strains differed significantly from serotypable organisms with the same biotype (P less than 0.001).
Septic arthritis involving Capnocytophaga ochracea
Authors: Winn R E , Chase W F , Lauderdale P W , McCleskey F K
Published: January 2020

Septic arthritis of the knee developed in a 21-month-old child. The causative organism, isolated from two separate arthrocenteses, was identified as Capnocytophaga ochracea morphologically and by biochemical reactions. Previous human infections (bacteremias) have occurred in granulocytopenic hosts with concomitant oral pathology including periodontitis and gingivitis. No abnormalities of oral hygiene were present in this patient, and granulocyte numbers were normal or elevated. Eradication of the infection was accomplished with 8 weeks of antibiotic therapy combined with surgical drainage. Septic arthritis expands the spectrum of infections reported to be caused by Capnocytophaga spp.
Flavobacterium multivorum septicemia in a hemodialyzed patient
Authors: Potvliege C , Dejaegher-Bauduin C , Hansen W , Dratwa M , Collart F , Tielemans C , Yourassowsky E
Published: January 2020

A case of Flavobacterium multivorum septicemia in a hemodialyzed patient is reported. Two blood cultures were positive at 48 h, and the patient became afebrile only after antimicrobial therapy. The origin of the septicemia could not be determined.
Identification of Salmonella O antigens by coagglutination
Authors: Cohen J O , Britt L E , Harrell W K
Published: January 2020

This study concerns the preparation of reagents for identifying the somatic O antigens of Salmonella enteritidis. Coagglutination reagents (COAGs) with antibody fixed to killed and stabilized protein A-bearing staphylococci were prepared with antisera which were used for identifying the somatic O antigens of S. enteritidis by the slide agglutination test. The reactions of the COAGs were compared with those obtained with the grouping antisera in routine slide agglutination tests in which 41 or more serologically different Salmonella strains, representing most of the known groups, were used. One-third of the COAGs gave identical reactions to those of the slide agglutination antisera. The reactions of the other COAGs varied from the slide agglutination antisera results, some by many reactions and others by only a few. The coagglutination procedure was more reactive than the routine slide agglutination test and resulted in cross-reactions which were not observed in the original grouping antisera. More COAGs were specific when they were tested with alcohol-treated cultures than with live cultures. Coagglutination conserves antiserum, allowing about 12 times as many tests for a given volume of group-specific glycerolized antiserum as does the slide agglutination method.
Antibody class capture assays for varicella-zoster virus
Authors: Forghani B , Myoraku C K , Dupuis K W , Schmidt N J
Published: January 2020

Pooled monoclonal antibodies to varicella-zoster virus (VZV) were used as "detector" antibodies in a four-phase enzyme immunofluorescence assay for determination of immunoglobulin M (IgM), IgA, and IgG antibodies to VZV. Polyclonal antisera specific for heavy chains of human IgM, IgA, and IgG were employed as "capture" antibodies on the solid phase. The antibody class capture assay (ACCA) for VZV IgM antibody detected high titers of virus-specific IgM in all patients with varicella and in 5 of 10 zoster patients. VZV IgM antibody was not detected in patients with primary herpes simplex virus infections or in other individuals without active VZV infection, with one exception, a patient with encephalitis who had other serological findings compatible with a reactivated VZV infection. VZV-specific IgA and IgG antibody titers demonstrable by ACCA were compared with those measured by solid-phase indirect enzyme immunofluorescence assay (EIFA). VZV IgA antibody titers detected in patients with varicella and zoster were variable and could not be considered to be reliable markers of active VZV infection. IgA antibody titers detected by ACCA tended to be higher than those demonstrated by solid-phase indirect EIFA in varicella and zoster patients. VZV IgG antibody titers detected by ACCA in patients with varicella, and to a lesser extent in zoster patients, were as high as or higher than those demonstrated by solid-phase indirect EIFA. However, ACCA was totally insensitive in detecting VZV IgG antibody in individuals with past infections with VZV and would not be a suitable approach for determination of immunity status to VZV.
Prospective systematic study of Yersinia spp. in dogs
Authors: Fukushima H , Nakamura R , Iitsuka S , Tsubokura M , Otsuki K , Kawaoka Y
Published: January 2020

A total of 93 Yersinia spp. were isolated from 68 of 252 dogs in Shimane Prefecture, Japan. The Yersinia spp. were 70 Yersinia enterocolitica isolates from 50 dogs, 2 Yersinia frederiksenii isolates from 2 dogs, 5 Yersinia intermedia isolates from 5 dogs, and 16 Yersinia pseudotuberculosis isolates from 16 dogs. Fifteen of 70 Y. enterocolitica isolates belonged to biotype 4 serotype O3 phagotype 8 (6 isolates), biotype 4 (maltose negative) serotype O3 phagotype 8 (4 isolates), biotype 3 (Voges-Proskauer and sorbose negative) serotype O3 phagotype 9 (2 isolates), and biotype 2 serotype O5.27 (3 isolates). The other 55 Y. enterocolitica isolates belonged to biotype 1 and were classified into serotypes O4, O5, O7 .8, O9, O10 , O12 , O13 .7, O14 , O15 , and untypable. Sixteen Y. pseudotuberculosis isolates belonged to serotypes IB (two), IIB (two), IVA (two), IVB (three), VA (five), and untypable (two). These isolates were mostly detected in cold months. Y. enterocolitica serotype O3 and Y. pseudotuberculosis were isolated more frequently from puppies. Y. enterocolitica serotype O3 was recovered at less than 10(7.0) cells per g of the jejunal-to-rectal contents and at less than 10(2) cells per g of mesenteric lymph nodes. Y. pseudotuberculosis was recovered at less than 10(4.3) cells per g of the cecal-to-rectal contents and at less than 10(2.9) cells per g of mesenteric lymph nodes. Almost all strains of Y. enterocolitica biotype 1, Y. intermedia, and Y. frederiksenii were recovered at less than 10(2) cells per g of gastric-to-rectal contents.
Comparison of standard tissue culture, tissue culture plus staining, and direct staining for detection of genital herpes simplex virus infection
Authors: Nerurkar L S , Namba M , Sever J L
Published: January 2020

Genital herpes simplex virus infection in women was studied by using conventional tissue culture (TC) virus isolation compared with short-term (24-h) TC on Lab-Tek chamber slides followed by fluorescent-antibody (FA) staining. Three different staining techniques were used after TC: (i) staining with biotin-avidin (TC-BA/FA), (ii) direct FA (TC-FA), and (iii) indirect FA. The TC-BA/FA method showed complete correlation with the TC method. The TC-FA method showed no false-positive results but 31.5% false-negative results compared with the TC method. In contrast, the TC-indirect FA method showed 11.9% false-positive results and 11.7% false-negative results. The direct staining of specimens by the biotin-avidin technique (direct BA/FA) without prior tissue culture showed 37.7% false-positive results and 11.1% false-negative results. The TC-BA/FA technique thus was as sensitive as, but more rapid than, the TC method. The quality of fluorescence was far superior in TC-BA/FA staining as compared with TC-FA or TC-indirect FA procedures. The TC-BA/FA appears to be a valuable technique in laboratory diagnosis of genital herpes infections, especially in clinical situations requiring rapid detection of the virus.
Clinical comparison of the Isolator 1.5 microbial tube and the BACTEC radiometric system for detection of bacteremia in children
Authors: Carey R B
Published: January 2020

The Isolator 1.5 microbial tube (E. I. du Pont de Nemours & Co., Inc., Wilmington , Del.) was compared with the BACTEC radiometric detection system (Johnston Laboratories, Inc., Cockeysville, Md.) for the detection of bacteremia in children. The Isolator 1.5 is a blood culture system designed for small volumes of blood (0.5 to 1.5 ml). The method involves lysis of the cells of the patient and the direct plating of the entire blood lysate on agar media appropriate for the growth of fastidious microorganisms. Of 1,500 paired samples inoculated into the two systems, 68 were positive for 73 clinically significant organisms. The Isolator 1.5 recovered 81% of the positive cultures compared with 84% recovered by the BACTEC system. When paired blood samples with disproportionate volumes were excluded, the Isolator 1.5 detected 3% more positive cultures. More isolates of Streptococcus pneumoniae and Neisseria meningitidis were recovered by the Isolator 1.5, whereas Haemophilus influenzae was recovered most often in the BACTEC bottles (P greater than 0.1). The contamination rates were 8.7 and 3.1% for the Isolator 1.5 and the BACTEC system, respectively. In cultures positive by both systems, the mean time to detection was 4.1 h faster with the Isolator 1.5. The mean time to obtain isolated colonies was 26.6 h faster with the Isolator 1.5. These data indicate the potential value of the Isolator 1.5 microbial tube as a simple, rapid, and sensitive method for the detection of bacteremia in children.
Serological identification of oral Bacteroides spp. by enzyme-linked immunosorbent assay
Authors: Ebersole J L , Frey D E , Taubman M A , Smith D J , Socransky S S , Tanner A C
Published: January 2020

A rapid method for identifying black-pigmented oral Bacteroides spp. is described. Species-specific rabbit antisera to Bacteroides gingivalis, B. intermedius, and B. melaninogenicus were used in an enzyme-linked immunosorbent assay to identify clinical isolates of black-pigmented Bacteroides spp. from humans. The results showed excellent agreement with biochemical identification of B. gingivalis and B. intermedius. Only 36% of the B. melaninogenicus isolates were identified with the enzyme-linked immunosorbent assay, suggesting that this group of black-pigmented Bacteroides spp. is made up of more than one serotype. The serological enzyme-linked immunosorbent assay should enable rapid identification of black-pigmented Bacteroides spp. isolated from sites of oral diseases and may also be used to identify the presence of these organisms in complex bacterial mixtures from oral sites.
Detection of Clostridium botulinum type A toxin by enzyme-linked immunosorbent assay with antibodies produced in immunologically tolerant animals
Authors: Dezfulian M , Bartlett J G
Published: January 2020

Immunological tolerance is a state of unresponsiveness to foreign substances (antigens) which can develop in human and animal species as the result of continued exposure to antigens early in life. We utilized this principle for the preparation of antibodies against Clostridium botulinum type A toxin. By selective suppression of the immunological response of rabbits to unwanted antigens and subsequent immunization with a toxoid, we were able to produce a specific type A antitoxin without the need to purify the toxin. Despite cross-reactivity with C. botulinum type B, our type A antitoxin was otherwise specific since it did not react with culture filtrates of nontoxigenic variants of type B, any other C. botulinum type (C, D, E, F, and G), nor with 18 other Clostridium species, including Clostridium sporogenes. Using this antitoxin, we developed a sensitive enzyme-linked immunosorbent assay for detection of C. botulinum type A toxin.
Antibody response to dengue-2 vaccine measured by two different radioimmunoassay methods
Authors: Summers P L , Eckels K H , Dalrymple J M , Scott R M , Boyd V A
Published: January 2020

Two different radioimmunoassays were used to detect virus-specific antibodies in sera from human volunteers inoculated with an attenuated dengue type 2 (DEN-2) vaccine (PR-159/S-1). An indirect radioimmunoassay required purified DEN-2 virions for optimal reactivity but was 10 to 500 times more sensitive than neutralization or hemagglutination inhibition tests. An antibody capture radioimmunoassay was able to utilize crude antigens from either DEN-infected mouse brains or Aedes albopictus cell culture supernatants. When the two radioimmunoassay techniques were compared, the indirect method appeared to be the best assay for immunoglobulin G (IgG), whereas the antibody capture method was more sensitive for IgM detection. Selected human sera were examined for IgG, IgM, and IgA responses by using both techniques at various intervals after immunization. Although there were differences in magnitude, yellow fever immune as well as flavivirus nonimmune volunteers responded to DEN-2 vaccination by demonstrating IgG, IgM, and IgA antibody responses. In the nonimmune group, the most prevalent immunoglobulin detected was IgM, whereas in the yellow fever immune group, the predominant post-DEN-2 vaccine immunoglobulin was IgG. The preponderance of DEN-2-specific neutralizing antibodies were associated with either IgM or IgG according to the immune status of the volunteer. All classes of immunoglobulins attained maximum levels between 21 and 60 days postvaccination. In the majority of volunteers, IgM responses were relatively transient and could not be detected 6 months after immunization, whereas IgG and IgA antibodies were still detectable after this period.
Evaluation of a rapid radiometric differentiation test for the Mycobacterium tuberculosis complex by selective inhibition with p-nitro-alpha-acetylamino-beta-hydroxypropiophenone
Authors: Laszlo A , Siddiqi S H
Published: January 2020

This study is an evaluation of a rapid technique for the differentiation of the Mycobacterium tuberculosis complex from other mycobacteria, using p-nitro-alpha-acetylamino-beta- hydroxypropiophenone (NAP) as a selective inhibitory agent. A total of 416 coded cultures, 234 cultures belonging to the M. tuberculosis complex and 182 cultures belonging to 35 other mycobacterial species, were tested in two laboratories for p-nitro-alpha-acetylamino-beta- hydroxypropiophenone inhibition to concentrations of 5 and 10 micrograms of NAP per ml in Middlebrook 7H12 liquid medium. Two testing modes were compared: the indirect, in which a large bacterial inoculum was used from an isolated culture on a solid medium, and the direct, which used a small inoculum from 7H12 medium. A decrease or no increase in daily 14CO2 output as measured by a BACTEC system was considered evidence of inhibition. The data presented show that a concentration of 5 micrograms of NAP per ml can effectively separate the M. tuberculosis complex from other mycobacterial species in 4 to 6 days. The direct test data show that, unlike other conventional biochemical tests, it does not require a heavy inoculum of mycobacteria and can therefore be performed soon after growth is detected by the radiometric method.
Specific identification of Salmonella serogroup E antigen O3 by immunofluorescence and coagglutination with antiserum elicited by a synthetic trisaccharide-bovine serum albumin glycoconjugate
Authors: Ekwall E , Norberg T , Svenson S B , Lindberg A A
Published: January 2020

Antiserum specific for Salmonella O3 antigen was raised by immunization of rabbits with an artificial glycoconjugate consisting of the synthetic trisaccharide beta-D- Manp (1----4)-alpha-L- Rhap (1----3)-alpha-D-Galp covalently linked to bovine serum albumin (beta- MRG -BSA). Enzyme immunoassays showed that only lipopolysaccharides extracted from Salmonella serogroup E (O3 antigen-containing) bacteria bound the antiserum. The usefulness of the beta- MRG -BSA antiserum for rapid and accurate identification of Salmonella isolates of serogroup E was shown by indirect immunofluorescence tests in which 50 Salmonella strains of serogroup E 1-4 were correctly identified from among 651 intestinal strains investigated. The finding that one strain of Citrobacter freundii was positive in immunofluorescence tests with this antiserum is readily explained by the known cross-reactivity between some C. freundii strains and Salmonella spp. strains of serogroup E. As expected, the specificity of the antiserum for the O3 antigen could further be demonstrated in coagglutination tests with staphylococci sensitized with beta- MRG -BSA antiserum.