bluuebunny/crossref_metadata_2025 huggingface dataset:
Superiority of hypertonic culture medium for detection of Haemophilus influenzae by the BACTEC procedure
Authors: Crist A E , Amsterdam D , Neter E
Published: January 2020

A comparison of hypertonic (sucrose), aerobic, and anaerobic media for the detection of eight recent clinical isolates of Haemophilus influenzae type b by the BACTEC procedure revealed that the hypertonic medium, without exception, yielded diagnostic growth index values of 30 or above from 4 to 24 h earlier than did the other media. This culture medium was also superior when an increase in growth index units of 10, before a value of 30 was reached, was taken as a criterion. The number of colony-forming units increased more rapidly in the hypertonic medium as compared with the other media. These results, together with limited observations on blood cultures from patients, suggest that the sucrose medium may permit earlier detection of H. influenzae bacteremia than the aerobic medium, particularly since a growth index of 20 rather than 30 is used for the indication of bacterial growth.
Effect of centrifugation and microagglutination techniques on Brucella agglutinin titers
Authors: Klein G C , Behan K A , Brown S L , Couch E E
Published: January 2020

The microagglutination technique without centrifugation was more effective than centrifugation of the standard tube test for increasing Brucella agglutinin titers of specimens with a titer greater than or equal to 160 but was less effective than centrifugation of the standard tube test for specimens with a titer less than 160.
Improved diagnostic medium for separation of Cryptococcus neoformans var. neoformans (serotypes A and D) and Cryptococcus neoformans var. gattii (serotypes B and C)
Authors: Kwon-Chung K J , Polacheck I , Bennett J E
Published: January 2020

A simple new agar medium containing L-canavanine, glycine, and bromthymol blue was found to give a clearer and more accurate distinction between serotype A or D (Cryptococcus neoformans var. neoformans) and serotype B or C (C. neoformans var. gattii) than creatinine-dextrose-bromthymol blue or glycine-cycloheximide-phenol red media. Among 143 isolates of serotype A or D and 70 isolates of serotype B or C, the new medium correlated completely with the serotype, whereas nearly 11% of these isolates gave discrepant reactions with creatinine-dextrose-bromthymol blue and glycine-cycloheximide-phenol red media.
Identification of Parainfluenza Virus Serotypes by Indirect Solid-Phase Enzyme Immunoassay
Authors: Parkinson A. J. , Scott E. N. , Muchmore H. G.
Published: January 2020

An indirect enzyme immunoassay was used to detect and identify parainfluenza virus serotypes 1 and 3 in cell culture residuals from which infectious virus could no longer be recovered.
Serotype and ampicillin susceptibility of Haemophilus influenzae causing systemic infections in children: 3 years of experience
Authors: Mason E O , Kaplan S L , Lamberth L B , Hinds D B , Kvernland S J , Loiselle E M , Feigin R D
Published: January 2020

Over a 3-year period, 96% of systemic infections in children caused by Haemophilus influenzae were of serotype b. Of 346 invasive infections, 15 (4%) were caused by non-type b H. influenzae. The monthly prevalence of ampicillin resistance in all isolates was highly variable (0 to 63%). Ampicillin resistance in H. influenzae causing invasive disease occurred in 13% of non-type b and 21.8% of type b isolates. There was no significant difference (x2 - 0.21; p greater than 0.10) in the rate of ampicillin resistance between type b and non-type b H. influenzae causing systemic illness in children over a 3-year period.
Comparison of acridine orange, methylene blue, and Gram stains for blood cultures
Authors: Mirrett S , Lauer B A , Miller G A , Reller L B
Published: January 2020

Direct microscopic screening of blood cultures by Gram stain or methylene blue stain is time consuming and frequently insensitive. Therefore, we evaluated a fluorescent-staining procedure that uses acridine orange (AO) at pH 3.5 and compared it with the methylene blue and Gram stain procedures. All smears were prepared within 24 h of receiving the culture, fixed with methanol, and examined without the results of the companion smears being known. AO-stained smears were examined with incident-light fluorescence at 600 x magnification and confirmed at 1,500x magnification. All bottles macroscopically positive within 24 h were excluded from the study. Of 2,946 cultures entered into the study, 204 (6.9%) were positive within 3 days. The sensitivity and specificity of AO based on these culture results were 52 and 98%, respectively, compared with 38% sensitivity and 99% specificity by methylene blue and Gram stains. The AO staining procedure is a simple, sensitive, screening technique for the early detection of positive blood cultures.
Pseudomonas aeruginosa skin infections in persons using a whirlpool in Vermont
Authors: Vogt R , LaRue D , Parry M F , Brokopp C D , Klaucke D , Allen J
Published: January 2020

Four guests at a ski resort in Vermont reported contracting a characteristic papular, pustular, or vesicular rash after using the resort's whirlpool. Pseudomonas aeruginosa serotype 1, bacteriophage type 86, was isolated from a pustule on one patient, water within the whirlpool, and the whirlpool diatomaceous earth filter. This appears to be the first outbreak of dermatitis associated with P. aeruginosa serotype 1. Previous reports of whirlpool-associated dermatitis outbreaks have identified serotype 9 and 11 isolates of P aeruginosa as the causative agents.
Identification of Enterobacteriaceae by the automicrobic system: Enterobacteriaceae biochemical cards versus Enterobacteriaceae-plus biochemical cards
Authors: Barry A L , Badal R E
Published: January 2020

Enterobacteriaceae Biochemical Cards (EBC) may be used in the AutoMicrobic system for identification of enteric bacilli. Recently, the card has been modified to permit identification of enteric and certain nonenteric bacilli. Also, minor modifications have been in the computer program used for interpretation of tests with the new cards (EBC+). The two types of cards (EBC and EBC+) were tested in parallel and found to be in agreement with 97% of 650 Enterobacteriaceae. Most of the discrepancies were resolved when selected strains were retested on 3 separate days. A lack of absolute reproducibility with either system was demonstrated and explained most of the initial discrepancies. Approximately 97% of the AutoMicrobic system identifications agreed with those obtained from standard reference methods, after equivocal AutoMicrobic system results (P less than 0.80) were excluded. Equivocal responses occurred with 4% of our EBC tests and 7% of our EBC+ tests; additional tests are needed before such strains can be identified with confidence.
Comparison of indirect fluorescent-antibody amoebic serology with counterimmunoelectrophoresis and indirect hemagglutination amoebic serologies
Authors: Garcia L S , Bruckner D A , Brewer T C , Shimizu R Y
Published: January 2020

Patients ranged from those with no prior diagnosis of or suspected exposure to Entamoeba histolytica to those with proven amoebic liver abscesses (extraintestinal disease). A comparison of serologies from patients with proven and suspected amoebiasis or possible past exposure revealed good correlation between the indirect fluorescent antibody (IFA) procedure and the other methods used, counterimmunoelectrophoresis and indirect hemagglutination. Titers from patients with proven extraintestinal amoebiasis were in the expected high range previously reported by other authors. Patients with clinical histories suggestive of exposure to E. histolytica but no proven disease had lower titers which indicated possible background exposure. The IFA procedure provides a rapid method of antibody detection; results obtained on an emergency basis provide essential information in making the diagnosis of amoebic abscess, pyogenic abscess, or tumor. The IFA procedure is rapid, reliable reproducible, and relatively inexpensive to perform, provided a good source of antigen is consistently available.
New radioimmunoadsorbent method for detection of hepatitis B surface antigen
Authors: Moore R P , Carpenter S K , Swartzell C T , Schick L A
Published: January 2020

A radioimmunoadsorbent assay for the detection of hepatitis B surface antigen (HBsAG) is described. The method uses small DEAE-cellulose columns to adsorb HBsAg from serum or plasma samples, and it uses 125 I-labeled antibody to HBsAg to detect the adsorbed antigen. A single 2-h incubation at 45 degrees C is used in the procedure. The sensitivity of the method was determined with the Bureau of Biologics HBsAg reference panels and was shown to be equivalent to other third-generation test methods. The specificity of the method was evaluated by testing specimens from blood donors, dialysis patients, and hospital staff in parallel with commercial radioimmunoassay kits for HBsAg. In the tests performed on 2,868 blood donor specimens, 6 positive specimens were identified by both the radioimmunoadsorbent method and the commercial radioimmunoassay kits. These positive specimens were confirmed by a counterimmunoelectrophoresis procedure. One nonconfirmable, repeatably positive specimen was observed with the radioimmunoadsorbent method. In testing 1,250 specimens from dialysis patients and hospital staff, 120 confirmable positive specimens were identified by both the radioimmunoadsorbent method and a commercial test. Overall, the false positive rate for the radioimmunoadsorbent method was found to be less than 1%.
Species identification and susceptibility to 17 antibiotics of coagulase-negative staphylococci isolated from clinical specimens
Authors: Marsik F J , Brake S
Published: January 2020

A total of 299 isolates of gram-positive, catalase-positive, coagulase-negative cocci were isolated from a variety of specimens collected from patients at a large university hospital, and 281 (94%) were identified as staphylococci by established methods. Using the scheme of Kloos and Schleifer, we determined the species of the coagulase-negative staphylococci. Staphylococcus epidermidis was the cause of all bacteremias and the most commonly isolated species from bone, joint, and wound infections. Staphylococcus haemolyticus was the second most common isolate from wound infections, and Staphylococcus saprophyticus was the most commonly isolated species from urinary tract infections. Antibiograms to 17 antimicrobial agents were performed by a microdilution technique, and the results revealed that S. epidermidis was resistant to a water spectrum of antimicrobial agents than the other species of staphylococci were.
In vitro evaluation of pyridine-2-azo-p-dimethylaniline cephalosporin, a new diagnostic chromogenic reagent, and comparison with nitrocefin, cephacetrile, and other beta-lactam compounds
Authors: Jones R N , Wilson H W , Novick W J
Published: January 2020

Pyridine-2-azo-p-dimethylanaline cephalosporin (PADAC), a chromogenic reagent which is purple and changes to yellow upon cleavage of its beta-lactam ring, was evaluated in comparison with other chromogenic cephalosporins. PADAC exhibited little antimicrobial activity against gram-negative bacteria, but did have good activity (minimum inhibitory concentration, 0.12 to 0.5 microgram/ml) against Staphylococcus aureus, a quality comparable to nitrocefin. Nitrocefin, however, demonstrated an unexpected and uniquely potent activity against Streptococcus faecalis (minimum inhibitory concentration, less than or equal to 0.06 to 0.12 microgram/ml) The relative hydrolysis rate of PADAC when subjected to six different beta-lactamases was substantially greater than that of cephacetrile, but less than that of nitrocefin. The relative hydrolysis rates of PADAC and nitrocefin were comparable with type IIIa beta lactamase and the derived from Bacillus cereus. The inhibition of beta-lactamase hydrolysis of the chromogenic cephalosporin substrates by six enzyme-stable inhibitors was generally greater with PADAC than with nitrocefin. Unlike nitrocefin, PADAC mixed with 50% human serum or various broth culture media showed no evidence of color change or degradation over several hours. The subsequent enzyme hydrolysis rates of such mixtures were the same as in phosphate buffer. Beta-lactamase-containing bacterial suspensions and clinical specimens containing such bacteria produced positive visual and spectrophotometric color changes when mixed with PADAC or nitrocefin. Although color changes occurred more slowly with PADAC than with nitrocefin, PADAC was not adversely influenced (non-enzyme-related color change) by the protein content of specimens. PADAC appears to be a promising alternative for beta-lactamase diagnostic testing in the clinical and research microbiology laboratory.
Increased indole detection for Pasteurella multocida
Authors: Clemons K V , Gadberry J L
Published: January 2020

A supplemented 2% peptone broth is described for the detection of indole production by Pasteurella multocida. The 96 isolates of P. multocida that were utilized in this evaluation were indole positive within 18 to 24 h.
Indirect hemagglutination test that uses glutaraldehyde-fixed sheep erythrocytes sensitized with extract antigens for detection of Pasteurella antibody
Authors: Sawada T , Rimler R B , Rhoades K R
Published: January 2020

Glutaraldehyde-fixed sheep erythrocytes (GA-SRBC) were used in the indirect hemagglutination test for the detection of Pasteurella antibody. GA-SRBC were stable for at least 6 months. Heat extract or potassium thiocyanate extract antigens of Pasteurella strains could be adsorbed onto GA-SRBC or tanned GA-SRBC, respectively. The indirect hemagglutination test reaction was capsular group specific with heat extract antigen-sensitized GA-SRBC but not potassium thiocyanate extract antigen-sensitized tanned GA-SRBC.
Serotyping of Campylobacter jejuni by slide agglutination based on heat-labile antigenic factors
Authors: Lior H , Woodward D L , Edgar J A , Laroche L J , Gill P
Published: January 2020

A serotyping scheme for Campylobacter jejuni was developed based on slide agglutination of live bacteria with whole cell antisera absorbed with homologous heated and heterologous unheated cross-reactive antigens. Among 815 isolates from human and nonhuman sources, 21 serogroups were recognized. Of the 615 isolates from human cases of gastroenteritis, 529 (86%) were typable; 455 strains agglutinated in 20 single antisera, whereas 74 isolates agglutinated in various pairs of antisera, allowing subdivision of some main serogroups into subserogroups. Of the 200 isolates of C. jejuni from nonhuman sources (chicken, swine, etc.), 166 (83%) were typable, 145 cultures agglutinated in various single antisera, and 21 strains agglutinated with different pairs of antisera. Among isolates from all sources, 8 serogroups (1, 2, 4, 5, 7, 8, 9, and 11) were encountered most frequently. Serogroups 1, 2, 4, 5, 7, 9, and 11 were most common among human isolates; the majority of the chicken and all of the swine isolates belonged to the same serogroups identified from human cases. Very good serological correlation was obtained in 20 family outbreaks and 4 community outbreaks.
Tentative interpretive standards for agar disk diffusion antimicrobial susceptibility testing of cefoperazone
Authors: Thornsberry C , Barry A L , Jones R N , Baker C N , Badal R E
Published: January 2020

Cefoperazone is a new cephalosporin with a very wide spectrum of activity, including activity against Pseudomonas aeruginosa. It has less activity on enterococci and Acinetobacter. Of the 459 selected bacterial strains tested in this study, only 1.5% (7 strains and 6 genera) had minimum inhibitory concentrations of greater than or equal to 128 micrograms/ml. For a minimum inhibitory concentration breakpoint of less than or equal to 32 micrograms/ml (susceptible), we recommend that the disk diffusion test be done with a 75-micrograms disk and breakpoints of greater than or equal to 18 mm for susceptible, 15 to 17 mm for intermediate, and less than or equal to 14 mm for resistant. Diffusion tests using these criteria yielded only 1.1% very major or major errors.
Comparison of different tobramycin assays
Authors: Stobberingh E E , Houben A W , van Boven C P
Published: January 2020

Three commercial available tobramycin assays, the fluorescent immunoassay (AMES), the Diagnostic Products Corp. radioimmunoassay, and the Nuclear Medical System radioimmunoassay, were compared with the microbiological assay and the chemical assay involving high-performance liquid chromatography. The results obtained with each assay were evaluated in terms of usefulness, reproducibility, and cost-effectiveness.
Evaluation and reporting of enzyme immunoassay determinations of antibody to herpes simplex virus in sera and cerebrospinal fluid
Authors: Cremer N E , Cossen C K , Hanson C V , Shell G R
Published: January 2020

Several methods for evaluating and reporting enzyme immunoassay (EIA) determinations of antibody to herpes simplex virus derived from one dilution of single serum samples were studied. An EIA ratio method for serological evidence of current infection from paired serum samples was also evaluated. Optical density (OD) of the reaction at a 1:100 serum dilution and estimated titers obtained by reference of the OD of the serum dilution to a standard curve were compared to the corresponding plotted EIA titer obtained by titration to endpoint. Neither the OD per se nor the estimated titer was completely predictive of the plotted titer (correlation coefficient [r] of 0.824 and 0.817, respectively), and they provided only a semiquantitative measurement of antibody concentration. For an antibody status report, however, OD would be sufficient if related to the cutoff value as an EIA index (OD of sample divided by cutoff OD for positive specimens). The OD of the EIA reaction at a single dilution (1:5) of cerebrospinal fluid, on the other hand, correlated quite well with the titer obtained by titration (r = 0.950). For serological diagnosis of current infection, the OD ratio of convalescence-phase/acute-phase sera was determined at several dilutions. A ratio of greater than or equal to 1.54 was calculated as a reliable index for a significant rise in antibody concentration and compatible with current infection. By determining the convalescent-phase/acute-phase serum ratio at two dilutions, 1:100 and 1:1,000, the EIA ratio method appeared to be a sensitive as or more sensitive than, complement fixation in diagnosing current infection.
Serological diagnosis of influenza B virus infection: comparison of an enzyme-linked immunosorbent assay and the hemagglutination inhibition test
Authors: Turner R , Lathey J L , Van Voris L P , Belshe R B
Published: January 2020

The sensitivity of an enzyme-linked immunosorbent assay (ELISA) for the detection of antibody to influenza B virus was compared with that of the hemagglutination inhibition test on acute- and convalescence-phase sera obtained from adults and children infected with influenza B virus. Two whole virus, tissue culture-grown antigen preparations were used in the ELISA, influenza B/West Virginia/81 and influenza B/Hong Kong/72. Four antigens were used in the hemagglutination inhibition test. These included the tissue culture-grown whole virus antigens that were used in the ELISA. In addition the standard egg-grown antigens, influenza B/Singapore/79 and influenza B/Hong Kong/72, were included for comparison. The ELISA antibody titer was significantly correlated to the hemagglutination inhibition antibody titer, and 10 of 10 adults and 17 of 21 children infected with influenza B had fourfold antibody increases as detected by ELISA with either antigenic type of tissue culture-grown whole virus. Increases in geometric mean antibody titers of 16- to 71-fold were detected by ELISA. Increases in geometric mean antibody titers of 3- to 10-fold were detected by hemagglutination inhibition depending on the type of antigen utilized. We found that ELISA with whole virus antigens was a sensitive and specific test for the detection of antibody to influenza B virus.
Evaluation of leukocyte esterase activity as a rapid screening technique for bacteriuria
Authors: Perry J L , Matthews J S , Weesner D E
Published: January 2020

Microscopy and leukocyte esterase activity, both employed as screening techniques for urine cultures, were evaluated with respect to two distinct populations, male and female. When 424 urine specimens from males were examined, 95% of the Gram-stained smears and 91% of the leukocyte esterase tests correctly correlated with culture results, indicating significant bacteriuria. There were no significant differences between the Gram stain and leukocyte esterase activity in predicting a negative culture: 99% and 98%, respectively. Neither microscopy nor esterase activity proved as sensitive or as efficient in predicting a negative culture with the female population.
Effect of diving and diving hoods on the bacterial flora of the external ear canal and skin
Authors: Brook I , Coolbaugh J C , Williscroft R G
Published: January 2020

The bacterial flora of the external ear canals and posterior auricular skin surfaces were investigated in a group of 26 divers after 25 dry-suit dives in harbor water and 20 dry-suit dives in clear test tank test. A control group of 16 divers wore rubber hoods 19 times for a similar period (25 to 30 min) but did not dive. The protective effect of 2% acetic acid was tested by instilling it in the left ear of 14 divers and 8 nondivers. Staphylococcus epidermidis, Propionibacterium acnes, alpha-hemolytic streptococci, and enteric gram-negative rods were the predominant isolates from skin and ear samples. After the divers dove or after they wore hoods without going in the water, there was a substantial increase in the number of these organisms on the skin (46.9%) or in the external ears (43.8%) of the divers. However, an increase in the bacterial counts in the external ear canals occurred in only 13.6% of the individuals treated prophylactically with acetic acid drops. Although no gram-negative rods were recovered from the skin or external ear canals of divers in clear tank water, 23 strains were isolated after the dives in harbor water. Identical gram-negative isolates also were recovered from the harbor water. Gram-negative organisms also were recovered from three newly acquired skin lacerations, where they persisted for at least 24 h. Our data show the acquisition of gram-negative rods when dives were made in polluted water. The data also demonstrate the increase in bacterial counts that occurs when rubber diving rods are worn (in or out of water) and that this increase can be controlled by pretreatment of ears with acetic acid.
Comparison of recovery of organisms from blood cultures diluted 10% (volume/volume) and 20% (volume/volume)
Authors: Auckenthaler R , Ilstrup D M , Washington J A
Published: January 2020

We compared blood cultures that were diluted 1:5 (20%, vol/vol) and 1:10 (10%, vol/vol) and contained specimens from patients with suspected septicemia. Streptococcus pneumoniae was recovered significantly more frequently from blood cultures diluted 20%, whereas gram-negative bacilli, group D streptococci, Staphylococcus aureus, and Candida spp. were recovered significantly sooner and more frequently from blood cultures diluted 10%. Statistically significant differences in isolation rates, however, represented only a small number of patients for whom the positive cultures affected therapy. We conclude that as long as at least two separate sets of blood cultures are obtained per septic episode from each patient, a 1:5 to 1:10 blood/vented (aerobic) medium ratio provides acceptable results. Nevertheless, the results also demonstrate that blood cultures diluted 10% provided greater and faster yields than those provided by blood cultures diluted 20%.
Expanded serotyping scheme for Ureaplasma urealyticum strains isolated from humans
Authors: Robertson J A , Stemke G W
Published: January 2020

For the last decade the serological heterogeneity of strains of Ureaplasma urealyticum isolated from humans has been represented by eight serotypes. We have identified two additional serotypes, strains Vancouver and Western. Using a modified metabolic inhibition test and a colony indirect epifluorescence method, we tested antisera to the above 10 types against the 11 members of the independent Lin-Kass classification. Four of the latter, K2, U24, U26, and U38, showed unique specificities; these were confirmed by reciprocal testing with antisera prepared against the respective strains. With the addition of these strains, the serotyping scheme now has 14 members. Since this expanded classification allows greater discrimination between strains, it will allow also for their future characterization. It provides, in addition, a potentially more effective epidemiological tool.
Detection of La Crosse arbovirus antigen in mosquito pools: application of chromogenic and fluorogenic enzyme immunoassay systems
Authors: Hildreth S W , Beaty B J , Meegan J M , Frazier C L , Shope R E
Published: January 2020

An enzyme immunoassay producing either a chromogenic or fluorogenic end product was developed and evaluated for detecting La Crosse viral antigen within mosquito pools. The enzyme immunoassay was found to be sensitive, detecting one infected mosquito within a pool of 100 mosquitoes, and specific, distinguishing between closely related California group viruses. Assays were completed within 5 h after the addition of test samples. La Crosse viral antigen could be readily detected in mosquito pools after seven freeze-thaw cycles.
Anaerobic survival of clinical isolates and laboratory strains of Neisseria gonorrhoea: use in transfer and storage
Authors: Short H B , Clark V L , Kellogg D S , Young F E
Published: January 2020

Eleven laboratory strains and 67 clinical isolates of Neisseria gonorrhoeae were tested for the ability to survive during anaerobic incubation. The survival of the laboratory strains was dependent on auxotype, temperature, and cell density on agar plates. For both the laboratory strains and the clinical isolates, anaerobic survival was better at lower temperatures. We concluded that anaerobic incubation, for as long as 7 days, is useful when transporting or storing N. gonorrhoeae.
Comparison of an enzyme immunoassay with electron microscopic procedures for detecting rotavirus
Authors: Rubenstein A S , Miller M F
Published: January 2020

The sensitivity and specificity of an enzyme immunoassay (Rotazyme), an ongrid immunoelectron microscopy procedure, and conventional negative stain electron microscopic techniques were compared. By using partially purified human rotavirus and simian rotavirus (SA-11) of known particle concentration, the enzyme immunoassay was essentially equivalent to the immunoelectron microscopic procedure and significantly more sensitive than conventional electron microscopic techniques. The level of sensitivity was approximately 10(6) particles per ml for simian rotavirus SA-11 and 10(7) particles per ml for human rotavirus. In an evaluation of 455 clinical samples by these techniques, a sensitivity of 98% and specificity of 92% were demonstrated. Samples negative by the immunoelectron microscopic procedure and positive by enzyme immunoassay could be confirmed by a blocking assay.
Comparison of rectal swabs and stool cultures in detecting Campylobacter fetus subsp. jejuni
Authors: Kaplan R L , Goodman L J , Barrett J E , Trenholme G M , Landau W
Published: January 2020

Rectal swabs and stool specimens were compared for the detection of Campylobacter fetus subsp. jejuni in marmosets. Rectal swabs were superior to stool specimens for detection of Campylobacter fetus subsp. jejuni (P = 0.016). Preliminary human data are also presented.
Studies of the specificity of Legionella serology
Authors: Wentworth B B , Stiefel H E
Published: January 2020

Sera with concurrent rises in titer to Legionella and mycoplasmal or chlamydial antigens were absorbed with whole Legionella organisms. Absorption removed Legionella reactivity only. No evidence of cross-reactivity between Legionella organisms and either Mycoplasma or Chlamydia organisms was found in studies of hyperimmune rabbit antisera.
Technique for extracting niacin from Mycobacterium tuberculosis cultured on 7H-10 and 7H-11 agars
Authors: Neimeister R
Published: January 2020

Niacin extractions from M. tuberculosis growing on 7H-10 or 7H-11 agar base medium yield consistent results when performed at 37 degrees C for 2 h. The technique does not require any modification of the media formulation.
Interaction between plant agglutinins and Legionella species
Authors: Doyle R J , Nedjat-Haiem F , Miller R D , Keller K F
Published: January 2020

Serogroups of Legionella pneumophila exhibited differential reactivities with plant agglutinin. Agglutination patterns were modified by growing the organisms in different media. The passage of four strains through guinea pigs did not result in altered reactivities with lectins or with plant agglutinins.
Evaluation of slide agglutination and ring precipitation tests for capsular serotyping of Haemophilus pleuropneumoniae
Authors: Mittal K R , Higgins R , Lariviere S
Published: January 2020

Rapid slide agglutination (RSA), quantitative plate agglutination, slow tube agglutination (STA), and ring precipitation (RP) tests were performed on 200 isolates of Haemophilus pleuropneumoniae by using the type sera produced in rabbits against five known serotype strains and one strain 202. RSA and RP tests both yielded the same results as those by STA. None of the agglutination procedures could be used for serotyping isolates that autoagglutinated in saline. The RP test was successfully used for serotyping such strains. The specificity of the RSA and RP tests was confirmed by cross-absorption studies. All of the isolates except two had strong serotype-specific activities. The most common serotype isolated in Quebec was serotype 1, followed by serotypes 5 and 2. None of the isolates belonged to serotypes 3 and 4. Only two isolates were found to be untypable; they could possibly belong to serotype(s) not yet defined. The RSA and RP tests may be at least as reliable as the STA test, but easier to perform, less expensive, and much more rapid than any of the other methods reported. Of all the procedures studied by us, the RP test proved to be the method of choice for serotyping H. pleuropneumoniae; hence, it should replace the STA test for serotyping H. pleuropneumoniae.
Clostridium difficile and its cytotoxin in feces of patients with antimicrobial agent-associated diarrhea and miscellaneous conditions
Authors: George W L , Rolfe R D , Finegold S M
Published: January 2020

Fecal specimens from 223 subjects were evaluated for the presence of Clostridium difficile by use of a selective medium developed in our laboratory and for the presence of C. difficile cytotoxin. C. difficile and cytotoxin were detected in 89 and 83%, respectively, of patients with antimicrobial agent-associated pseudomembranous colitis (PMC). In patients in whom PMC was not documented, C. difficile and cytotoxin were present in only 37 and 21%, respectively. C. difficile and cytotoxin were also recovered from the feces of 6 and 3, respectively, of 13 antimicrobial recipients who did not have diarrhea. Although C. difficile appears to be a major cause of PMC, it is not responsible for at least some two-thirds of cases of antimicrobial agent-associated diarrhea in which PMC is not documented. Neither the recovery of C. difficile nor the detection of its cytotoxin should be considered diagnostic for C. difficile-induced disease.
Detection by enzyme-linked immunosorbent assays of antibody specific for Pseudomonas proteases and exotoxin A in sera from cystic fibrosis patients
Authors: Jagger K S , Robinson D L , Franz M N , Warren R L
Published: January 2020

Enzyme-linked immunosorbent assays were developed to measure serum antibody specific for Pseudomonas elastase, alkaline protease, and exotoxin A. Antibody responses to each Pseudomonas antigen were measured in cystic fibrosis (CF) patients who were not colonized with Pseudomonas aeruginosa, in those who were colonized, in those who were chronically infected with this organism, and in control subjects. Antibody levels for each antigen in the colonized and infected CF patients were higher than levels in uncolonized CF patients or non-CF control subjects. The antibody responses to elastase were similar in patients of the colonized and infected groups. However, infected CF patients had significantly elevated levels of antibody to exotoxin A (P less than 0.01) and alkaline protease (P less than 0.05) when compared with patients simply colonized with P. aeruginosa. These findings confirm that Pseudomonas alkaline protease, elastase, and exotoxin A are produced by Pseudomonas strains which colonize and infect CF patients. As an adjunct to established procedures (X-ray, microbiological culture, etc.), the antitoxin and anti-protease enzyme-linked immunosorbent assays may be clinically useful tests for differentiating colonized CF patients from those who have more severe Pseudomonas pulmonary infections.
Frequency of Escherichia coli strains producing heat-labile toxin or heat-stable toxin or both in children with and without diarrhea in São Paulo
Authors: Reis M H , Guth B E , Gomes T A , Murahovschi J , Trabulsi L R
Published: January 2020

Enterotoxigenic Escherichia coli strains were isolated from 32 (13.4%) of 245 children with diarrhea and from 11 (11.4%) of 96 children of the control group. Strains producing heat-labile toxin were found more frequently in normal children than in children with diarrhea. Strains producing heat-stable toxin and both heat-labile and heat-stable toxins were isolated only from children with diarrhea. Association of these strains with diarrhea was highly significant as shown by statistical analysis. The O:H types and the colonization factors of strains producing heat-stable toxin and both heat-labile and heat-stable toxins are presented.
Evaluation of Two
Salmonella typhi
Strains with Reduced Virulence for Use in Teaching and Proficiency Testing
Authors: Hickman F. W. , Rhoden Dwane L. , Esaias Ann O. , Baron L. S. , Brenner Don J. , Farmer J. J.
Published: January 2020

A total of 21 cases of laboratory-acquired typhoid fever associated with teaching and proficiency tests occurred in the United States during a 33-month period, prompting a search for less virulent strains of
S. typhi
which would be suitable for teaching purposes. Two strains were evaluated which are reported to have reduced virulence for mice. Strain Ty21a is a genetically constructed mutant that lacks the enzyme UDP-glucose-4-epimerase. This strain has reduced virulence for humans if grown under special laboratory conditions (in the presence of 0.1%
d
-galactose) and has been evaluated as a candidate for use as a live, oral vaccine. Strain H901 was originally isolated in Russia in 1918. It has not been tested in humans, but its nonmotile variant, O901, has been found to be somewhat less virulent for humans; however, it can cause infection with doses of 10
7
organisms. In teaching exercises, all strains should be treated as though they are fully virulent. Ty21a and H901 were satisfactory, but not ideal, for teaching purposes. Biochemically, they could be identified by conventional tests and by commercially available diagnostic systems, although Ty21a was H
2
S negative. Serologically, both strains posed problems. Both Ty21a and H901 were Vi antigen negative, and Ty21a was rough and grew poorly. Both strains were susceptible to antibiotics, including chloramphenicol, ampicillin, and trimethoprim-sulfameth-oxazole. When Ty21a and H901 were mixed with
Escherichia coli
and plated, Hektoen and salmonella-shigella agars were most useful for their recovery. The appearance of Ty21a and H901 on differential plating media was typical, although Ty21a had smaller colonies. The plating efficiency on MacConkey agar for Ty21a was 0.6 compared with 1 for H901. Neither strain can be recommended unequivocally for teaching purposes; instead, the advantages and disadvantages of each must be considered. Both strains have been deposited in the American Type Culture Collection (Ty21a = ATCC 33459 = CDC 2861-79; H901 = ATCC 33458 = CDC 2862-79).
Novel approach to bacterial identification that uses the autobac system
Authors: Sielaff B H , Matsen J M , McKie J E
Published: January 2020

A new system for the rapid identification of gram-negative bacilli on the Autobac system is described. This system utilizes growth inhibition profiles to a panel of differentially inhibitory chemical agents. These profiles are analyzed with a two-stage quadratic discriminant analysis to arrive at the organism identification. The system identifies 30 different groups of gram-negative bacilli, including the most clinically significant Enterobacteriaceae and glucose nonfermenters. A total of 3,726 strains, distributed among the 30 groups, was tested. The Autobac system agreed with the conventional biochemical identification 88.4% of the time. When the individual group results were weighted to reflect clinical frequency, the result was a 93.1% agreement.
Novel method of biotyping Haemophilus influenzae that uses API 20e
Authors: Holmes R L , DeFranco L M , Otto M
Published: January 2020

One hundred Haemophilus influenzae isolates from various body sites were biotyped by conventional methods and by the API 20E system (Analytab Products, Plainview, N.Y.). By using a hemin- and a nicotinamide adenine dinucleotide-enriched saline solution as the inoculating fluid for the API 20E, a 100% correlation of results was obtained between the two methods. Ninety percent of the blood and cerebrospinal fluid isolates were biotype I. Biotype II was the predominant biotype encountered overall. No correlation was observed between beta-lactamase production and biotype. The API 20E is a reliable method and should prove useful for routine biotyping of H. influenzae in the clinical laboratory.
Detection of "neutral" type 7F and type 14 pneumococcal capsular polysaccharides by immunoelectrophoresis
Authors: Szu S C , Oravec L S
Published: January 2020

Type 7F and type 14 pneumococcal capsular polysaccharides, neutral at pH 8.6, were studied by immunoelectrophoresis at pH 5. Three techniques were used: rocket, countercurrent, and reversed immunoelectrophoresis. Our results show that these two capsular polysaccharides types can be detected at pH 5 with high sensitivity.
Antiserum-agar plate method for simultaneous detection and direct isolation of Legionella species in clinical and environmental specimens
Authors: Janssen W A , Hedlund K W
Published: January 2020

Colonies of Legionella pneumophila serotypes 1 through 6, L. micdadei, L. bozemanii, L. dumoffii, and L. gormanii, which were developed on filtered yeast extract agar containing polyvalent antiserum, were surrounded by distinct, specific precipitin rings.
Identification of Staphylococcus hyicus with the API staph strip
Authors: Maddux R L , Koehne G
Published: January 2020

The API Staph Strip system (API System S.A., Montalïeu-Vercieu, France) was compared with conventional methods for identification of Staphylococcus hyicus isolated from cases of exudative epidermitis in swine. The API Staph Strip was found to provide unique profile numbers, namely, 6-514-151, 6-514-153, and 6-516-153. These profile numbers are not listed in the API Staph Strip data base. It was found that the use of this miniaturized system is preferable to conventional methods for the identification of the causal agent of swine exudative epidermitis.
Detection of pneumococci in the upper respiratory tract: comparison of media and culture techniques
Authors: Robins-Browne R M , Kharsany A B , Ramsaroop U G
Published: January 2020

A survey for carriers of Streptococcus pneumoniae among 573 children was undertaken. Throat and nasopharyngeal cultures from 303 children disclosed pneumococci in 89 (29.4%) nasopharyngeal swabs but in only 8 (2.6%) throat specimens. Carriers of pneumococci were detected with frequencies of 84.4 and 79.9% on aerobically incubated 5% horse blood agar with a 5-micrograms optochin disk and on 5% horse blood agar with 5 mg of gentamicin per liter, respectively. Anaerobically incubated 5% horse blood agar yield pneumococci from 78.2% of 179 carriers. We consider the examination of nasopharyngeal secretions for optochin-susceptible alpha-hemolytic bacteria to be the most sensitive and convenient means for detecting carriers of pneumococci.
In vitro lymphocyte proliferation in response to type III group B streptococci
Authors: Lillie M A , Cody C S , Douglas S D , Polin R A
Published: January 2020

The in vitro cell-mediated responses to group B streptococci (GBS) and the relationship of cell-mediated immunity to specific humoral immunity to type III GBS were investigated. Blood was obtained from 20 adult volunteers, and lymphocytes were isolated and cultured in microtiter plates. Each well contained 2 x 10(5) lymphocytes, 15% autologous serum, and either GBS (cell-to-organism ratio of 1:10, 1:1, or 1:0.1), phytohemagglutinin, streptokinase-streptodornase, or RPMI 1640. Cells were harvested at 5, 6, or 7 days, and DNA synthesis was quantitated. Serum antibody titers were determined with an enzyme-linked immunosorbent assay. Maximal lymphocyte responses occurred at 6 days of culture and at a cell-to-organism ratio of 1:1. Individuals with significant antibody titers to type III GBS, as well as those with undetectable antibody, responded to GBS (stimulation index greater than 10). There was a significant difference (P less than 0.001) between mean antibody concentrations in responders (stimulation index greater than 10) and nonresponders (stimulation index less than 10). Thus, the in vitro responses to GBS may be both to a specific antigen and to a nonspecific mitogen and may be important in host immunity to GBS.
New human adenovirus associated with respiratory illness: candidate adenovirus type 39
Authors: Hierholzer J C , Kemp M C , Gary G W , Spencer H C
Published: January 2020

A new human adenovirus was isolated from a stool specimen from a 2-year-old El Salvadorian male hospitalized with severe respiratory illness. The virus, strain D335, is a typical adenovirus by routine classification tests and bears little resemblance to the other 38 adenovirus serotypes by standard hemagglutination inhibition and serum neutralization tests. The only significant cross-reaction observed was between adenovirus types 39 and 13, bilaterally, by the hemagglutination inhibition test. The virus was clearly differentiated from the other human adenoviruses by restriction enzyme analyses with SmaI, SacI, and KpnI enzymes. Strain D335 agglutinates human and rat erythrocytes to moderately high titers and is placed in hemagglutination subgroup 2B on the basis of differential hemagglutination with erythrocytes from 13 animal species. It has a density in cesium chloride of 1.339 g/ml and produces soluble components in human embryonic kidney culture that band at 1.303 g/ml (hexon), 1.283 g/ml (dodecon), and 1.212 g/ml (fiber), the last component being the only incomplete hemagglutinin found. The viral DNA is cleaved into 17 fragments by the SmaI restriction enzyme, indicating that strain D335 is a member of adenovirus subgenus D. Strain D335 is herein described as candidate adenovirus type 39 (Mastadenovirus h 39).
Antigenic Heterogeneity of Hemagglutination Type VI Fimbriae Produced by
Escherichia coli
Isolated from Patients with Bacteremia
Authors: Clegg Steven , Evans Doyle J. , Evans Dolores G.
Published: January 2020

In previous work it was observed that the majority of
Escherichia coli
strains isolated from the blood of bacteremia patients possess fimbriae which mediate mannose-resistant hemagglutination (HA) of human and monkey erythrocytes; this HA pattern (HA type VI) is different from those of enterotoxigenic
E. coli
possessing the colonization factor antigen CFA/I or CFA/II, which are also mannose-resistant HA positive. We and other investigators have found that HA type VI fimbriae may function as colonization factor antigens, especially in urinary tract infections. The work reported here was concerned with determining the number of antigenic types of fimbriae responsible for the HA type VI property. Fimbriae were isolated by hydrophobic interaction chromatography from four isolates of
E. coli
possessing the same HA pattern but belonging to different serotypes; antifimbrial antiserum was prepared by hyperimmunization of rabbits. Homologous and heterologous antifimbrial antibody titers were determined by the indirect enzyme-linked immunosorbent assay, bacterial agglutination by the tube method, and the HA inhibition test. Antiserum against the fimbriae of strain LY-71 (O4:H1) produced a high homologous titer but low or insignificant titers with fimbriae of strains LY-63 (O6:H31), LY-154 (O25:H
−
) and LY-156 (O2:H
−
). Antiserum against the fimbriae of strain LY-63 produced high titers with its own and with LY-71 fimbriae but insignificant titers with the fimbriae of strains LY-154 and LY-156. LY-154 and LY-156 fimbriae were highly cross-identical but antigenically different from those of LY-63 and LY-71. Twenty-five other test strains all identified with at least one of the prototype strains, as determined by HA inhibition tests performed with the four antifimbrial sera, although these belonged to a wide variety of serotypes. These data indicate the existence of at least two major different antigenic types of HA type VI fimbriae and possibly three, depending on the nature of the unidirectional crossidentity observed between the fimbriae of strains LY-63 and LY-71.
Shedding of rotavirus in feces of sows before and after farrowing
Authors: Benfield D A , Stotz I , Moore R , McAdaragh J P
Published: January 2020

The purpose of this study was to determine whether sows shed rotavirus near the time of farrowing. Twelve sows purchased from a common source and seropositive for rotavirus were housed in isolation in farrowing crates from 5 days before to 3 weeks after farrowing. Fecal samples were collected at 3- to 4-day intervals and examined for the presence of rotavirus by direct electron microscopy. Samples were also treated with pancreatin and inoculated onto monkey kidney cells. Rotaviral antigens were detected by a direct immunofluorescence technique, and selected positive cultures were examined by immunoelectron microscopy. Rotavirus was detected in the feces of 5 of 12 sows as early as 5 days before to 2 weeks after farrowing. Diarrhea related to rotavirus developed in 4 of 12 litters. Two of these four litters were farrowed by sows which shed rotavirus at 7 and 10 and 14 days after farrowing. The results of this study indicate that sows immune to rotavirus can shed virus in their feces at a time when piglets are particularly susceptible to infection and that adult swine are of primary importance in the epidemiology of rotavirus as initiators of infection.
Identification and typing of herpes simplex viruses with monoclonal antibodies
Authors: Balachandran N , Frame B , Chernesky M , Kraiselburd E , Kouri Y , Garcia D , Lavery C , Rawls W E
Published: January 2020

Monoclonal antibodies which reacted with type-specific antigens of herpes simplex virus type 2 or with antigens shared by herpes simplex virus types 1 and 2 were used in an indirect immunofluorescence assay to type virus isolates and to detect viral antigens in cells obtained from herpetic lesions. Complete concordance was obtained for 42 isolates typed by endonuclease restriction analysis of viral DNA and by indirect immunofluorescence with monoclonal antibodies. Examination of a limited number of ulcerative lesions revealed that indirect immunofluorescence and virus isolation were comparable in detecting herpes simplex virus. The results indicate that monoclonal antibodies can be used to accurately identify and type isolates of herpes simplex virus.