bluuebunny/crossref_metadata_2025 huggingface dataset:
Inactivation of Lassa, Marburg, and Ebola viruses by gamma irradiation
Authors: Elliott L H , McCormick J B , Johnson K M
Published: January 2020

Because of the cumbersome conditions experienced in a maximum containment laboratory, methods for inactivating highly pathogenic viruses were investigated. The infectivity of Lassa, Marburg, and Ebola viruses was inactivated without altering the immunological activity after radiation with Co60 gamma rays. At 4 degrees C, Lassa virus was the most difficult to inactivate with a rate of 5.3 X 10(-6) log 50% tissue culture infective dose per rad of CO60 radiation, as compared with 6.8 X 10(-6) log 50% tissue culture infective dose per rad for Ebola virus and 8.4 X 10(-6) log 50% tissue culture infective dose per rad for Marburg virus. Experimental inactivation curves, as well as curves giving the total radiation needed to inactivate a given concentration of any of the three viruses, are presented. We found this method of inactivation to be superior to UV light or beta-propiolactone inactivation and now routinely use it for preparation of material for protein-chemistry studies or for preparation of immunological reagents.
Rotavirus and hemolytic enteropathogenic Escherichia coli in weanling diarrhea of pigs
Authors: Lecce J G , Balsbaugh R K , Clare D A , King M W
Published: January 2020

Since the turn of the century, Escherichia coli has been implicated in the etiology of weanling diarrhea (colibacillosis). However, rotavirus--a virus that destroys enterocytes--has been shown recently to be causally associated with weanling diarrhea of pigs. The role of both rotavirus and hemolytic enteropathogenic E. coli in weanling diarrhea was assessed in this study. Pigs from a closed herd were farrowed and weaned by two markedly different systems: an "intensive care sanitary" system and a "conventional unsanitary" system. Pigs weaned at 3 weeks of age in the sanitary system usually experienced a rotaviral diarrhea about 16 days postweaning. No hemolytic E. coli were detected in feces from these pigs. Peers weaned at the same time by the unsanitary system commenced diarrhea 3 days postweaning. Rotavirus and nonhemolytic E. coli were detected in the feces at the onset of diarrhea and for a few days thereafter. Then, the aerobic fecal flora shifted to nearly pure hemolytic enteropathogenic E. coli. About 10 days later, the diarrhea waned, and the fecal flora shifted back to nonhemolytic E. coli. This hemolytic E. coli shedding pattern could not be duplicated in artificially inoculated sanitary pigs unless they were inoculated with the hemolytic E. coli during a rotaviral-associated diarrhea. Otherwise, the shedding of hemolytic E. coli was fleeting, and the diarrhea, if present, was mild. Pigs developed humoral antibodies to the rotavirus but not to the hemolytic E. coli. We conclude that rotavirus damages the epithelium of the small intestines, which changes the luminal environment to one that favors colonization by enteropathogenic E. coli.
Epidemiology of Rotavirus Diarrhea in Yogyakarta, Indonesia, as Revealed by Electrophoresis of Genome RNA
Authors: Albert M. John , Soenarto Yati , Bishop Ruth F.
Published: January 2020

Nine different electropherotypes of rotaviruses occurred among 85 children with rotavirus diarrhea in Yogyakarta, Indonesia. Eighty percent of the electropherotypes had a “long” RNA pattern characteristic of human subgroup 2.
Microtiter-Adapted Method That Facilitates the Coombs Test for Brucellosis
Authors: Otero Joaquín R. , Fuertes Antonio , Palenque Elia , Noriega Antonio R.
Published: January 2020

A simple method for carrying out the Coombs test with U-shaped microtiter plates instead of tubes is described. This technique provides reliable and more rapid testing of large numbers of sera in suspected cases of human brucellosis.
Screening for penicillin tolerance in viridans streptococci by a simple disk method
Authors: Dankert J , Holloway Y , Joldersma W , Hess J
Published: January 2020

A disk method was developed for demonstrating penicillin tolerance in viridans streptococci. This was achieved by the substitution of the penicillin disk used for susceptibility testing by a disk containing penicillinase. After reincubation, penicillin-tolerant strains exhibited new growth in the area adjacent to this disk, providing a rapid screening test.
Production of Phenylacetic Acid by Anaerobes
Authors: Mayrand D. , Bourgeau G.
Published: January 2020

We tested 388 strains of anaerobes from 17 genera for the production of phenylacetic acid. The compound was found in only two genera (
Bacteroides
and
Clostridium
) but not within all the species of these genera.
Serological diagnosis of Toxoplasma gondii infections by rapid separation of serum immunoglobulins M and G with CM Bio-Gel A
Authors: Ordonez G A , Newman J T , Stone M J
Published: January 2020

A simple and rapid method has been developed for the separation of serum immunoglobulin M (IgM) and IgG. CM Bio-Gel A chromatography was used in the technique, which resulted in an IgM-rich fraction containing 31% of the original serum IgM and less than 2% of the serum IgG. The procedure was used to detect masked IgM antibodies in patients suspected of having Toxoplasma gondii infections.
Factitious Bacterial Meningitis Revisited
Authors: Peterson E. , Thrupp L. , Uchiyama N. , Hawkins B. , Wolvin B. , Greene G.
Published: January 2020

Nonviable gram-negative bacilli were seen in smears of cerebrospinal fluid from eight infants in whom bacterial meningitis was ruled out. Tubes from commercial kits were the source of the factitious organisms.
Clinical laboratory evaluation of a reverse CAMP test for presumptive identification of Clostridium perfringens
Authors: Buchanan A G
Published: January 2020

Ninety-six percent of Clostridium perfringens isolates from clinical specimens were reverse CAMP test positive, whereas several other Clostridium species tested were reverse CAMP test negative. C. perfringens was detected by direct inoculation of clinical specimens to reverse CAMP plates, and the reverse CAMP procedure provided reliable presumptive identification of this organism.
Monoclonal antibodies for rapid, strain-specific identification of influenza virus isolates
Authors: Schmidt N J , Ota M , Gallo D , Fox V L
Published: January 2020

Monoclonal antibodies conjugated with fluorescein permitted rapid, strain-specific identification of influenza A isolates and type-specific identification of influenza B isolates by direct immunofluorescence staining. Identification of H1 influenza A strains could be accomplished by direct immunofluorescence on cell culture fluids lacking sufficient hemagglutinin activity to permit identification by hemagglutination inhibition.
Coreactivity of Legionella pneumophila immune sera in the Mycoplasma pneumoniae complement fixation test
Authors: Berdal B P , Eng J
Published: January 2020

Sheep and guinea pigs were immunized with cellular and extracellular antigen from Legionella pneumophila bacteria. After immunization, the animals developed immunoglobulin G titers against the immunizing agent. The same sera were also tested in a Mycoplasma pneumoniae complement fixation test. All the preimmunization sera from sheep showed positive M. pneumoniae complement fixation tests of varying titers, with significant antibody rises in two of five sheep as a result of the Legionella immunizations. In contrast to the sheep, all the guinea pigs were negative in the M. pneumoniae complement fixation test, both in their preimmunization sera and after completion of the Legionella immunizations. The results obtained with the sheep sera may be explained as a nonspecific booster effect of Legionella bacteria upon previously elicited immune responses.
Application of potassium thiocyanate as a destaining agent for confirming the specificity of viral immunofluorescence
Authors: Greenham L W , Caul E O
Published: January 2020

A study was made of the destaining effects of various agents on measles-infected monolayers which were stained by the indirect method of immunofluorescence. It was found that KSCN, a chaotropic agent, gave the required destaining but was nonspecific in its action, removing antigen as well as adsorbed immunoglobulins. By using a KSCN-EDTA destaining solution, it was shown that two sequential restainings of infected monolayers were possible, which permitted the demonstration of the specificity of the observed immunofluorescence. The technique may be of particular use with clinical specimens in which relatively few cells give immunofluorescence and when the specificity of this fluorescence is questioned.
Haemophilus pleuropneumoniae serotyping
Authors: Rosendal S , Boyd D A
Published: January 2020

A total of 126 Haemophilus strains isolated from porcine pneumonia were serotyped, using the indirect fluorescent-antibody technique. Of these, 103 were successfully typed within the recognized scheme of serotypes 1 to 5. Eleven strains were antigenically similar but were different from other strains of H. pleuropneumoniae or H. parasuis. These strains are proposed as serotype 7. Eight strains were not identified as serotype 1 when serum against strain Shope 4074 was used, but their identity as type 1 strains was concluded on the basis of complete cross-titrations, using unabsorbed and absorbed sera and indirect fluorescent-antibody and agglutination tests. The type-specific antigen of these strains may have been masked by an additional antigen. A similar situation was believed to exist for four strains which belonged to serotype 5 but did not react with serum against strain K17 (reference strain) in the indirect fluorescent-antibody test. Strain Femø was antigenically different from other H. pleuropneumoniae or H. parasuis strains and was proposed as serotype 6, thus replacing the "minor group" (represented by strain 202), which is of uncertain taxonomical status within the genus Haemophilus.
Comparison of methods for cultivation and isolation of Chlamydia trachomatis
Authors: Benes S , McCormack W M
Published: January 2020

McCoy cells treated with cycloheximide, iododeoxyuridine, and DEAE-dextran and untreated McCoy cells were inoculated with two stock strains of Chlamydia trachomatis and with 231 urethral specimens from men, 53 (23%) of which contained C. trachomatis. Isolation rates, number and quality of inclusions, and quality of the cell monolayers were compared. There were no significant differences between the isolation rates in the four systems, although the most isolations were made in the untreated and cycloheximide-treated cells. Cycloheximide-treated cells produced, from both the clinical specimens and the two stock strains, significantly more inclusions than any of the other systems. The monolayer of the cycloheximide-treated cells and the inclusions that grew in these cells were optimal for examination and detection of C. trachomatis.
Epidemiology of Klebsiella antibiotic resistance and serotypes
Authors: Smith S M , Digori J T , Eng R H
Published: January 2020

Because of the emergence of drug-resistant Klebsiella strains in many hospitals, the distribution of the serotypes was reexamined to determine whether there was any correlation between the serotype and the site of isolation from the body, the antimicrobial susceptibility pattern, or the place of acquisition of the organism (hospital or community). One hundred consecutive isolates of Klebsiella pneumoniae from different patients were typed as 1, 2, 3, 4, 5, 6, or greater than 6. Of these, 8 of 28 strains isolated from respiratory secretions were serotype 2 (9 typable strains), 6 of 24 wound isolates were serotype 3 (8 typable strains), and the urine isolates varied in their serotypes. Regardless of serotype, most strains appeared mucoid on blood and MacConkey agars. Twenty-six percent of the isolates were resistant to at least one antimicrobial agent. No correlation was found between the serotypes and the antibiotic resistance; however, strains isolated within 25 days of admission to the hospital from the community were all susceptible. It appears that although there may be a correlation between the serotype and isolation from some sites of the body, knowledge of the serotype of the organism cannot predict the antimicrobial susceptibility pattern. The clinician's choice of antibiotic therapy should depend largely on whether the Klebsiella strain was acquired by the patient in the community (0% resistant) or in the hospital (31% resistant).
Evaluation of the AutoMicrobic system for identification of yeasts
Authors: Hasyn J J , Buckley H R
Published: January 2020

The AutoMicrobic system (Vitek Systems, Hazelwood, Mo.) for identification of yeasts was evaluated by testing 352 freshly isolated, germ tube-negative yeasts from clinical laboratories. Of these isolates, 84.9% were correctly identified. The system correctly identified 86.5% of the Candida isolates and 74.3% of the Cryptococcus isolates.
Detection of yeasts and filamentous fungi in blood cultures during a 10-year period (1972 to 1981)
Authors: Bille J , Stockman L , Roberts G D
Published: January 2020

During a 10-year period (January 1972 to December 1981), 69,066 fungal blood cultures were performed by using a biphasic brain heart infusion medium. A total of 838 fungi were recovered from 302 patients. Candida species represented 71% (595) of all positive cultures, Cryptococcus neoformans 12.6% (106), and Histoplasma capsulatum 13.1% (110).
New latex agglutination test for rapid determination of rubella immune status
Authors: Weissfeld A S , Sonnenwirth A C
Published: January 2020

A prototype rubella latex agglutination card assay (Hynson, Westcott and Dunning, Baltimore, Md.) was compared with a standard hemagglutination inhibition test for the detection of rubella antibodies in 500 sera. The sensitivity and specificity of the latex agglutination assay were 100% and 94%, respectively. This assay did not require pretreatment of serum, and the entire assay could be performed in 10 min.
Serodiagnosis of acute hepatitis B virus infection by a modified competitive binding radioimmunoassay
Authors: Schable C A , Maynard J E
Published: January 2020

Using the Staphylococcus aureus absorption method, we have modified a commercial radioimmunoassay kit for the determination of total antibody to hepatitis B core antigen so that we can now determine the predominant globulin species of that antibody. One-hundred percent of acute hepatitis B sera had a predominance of immunoglobulin M antibody to hepatitis B core antigen, whereas immunoglobulin G antibody to hepatitis B core antigen was predominant in 98.2% of chronic hepatitis B surface antigen carriers. With this test and the commercially available tests for immunoglobulin M anti-hepatitis A virus, one can now reasonably differentiate acute hepatitis B from non A/non B hepatitis in a chronic hepatitis B surface antigen carrier.
Nature and identification of Exophiala werneckii
Authors: Mok W Y
Published: January 2020

The morphological and physiological characteristics of 44 isolates of Exophiala werneckii recovered from human and environmental sources were indistinguishable from 2 isolates that caused tinea nigra. Casein hydrolysis and inability to decompose tyrosine differentiate E. werneckii from Exophiala jeanselmei, Exophiala spinifera, and Wangiella dermatitidis.
Diarrhea Associated with
Vibrio fluvialis
in the United States
Authors: Tacket Carol O. , Hickman Frances , Pierce Gloria V. , Mendoza Luis F.
Published: January 2020

We report the isolation in the United States of
Vibrio fluvialis
from the stools of a patient who had severe watery diarrhea without fever and who subsequently died.
V. fluvialis
, a known enteric pathogen in other parts of the world, should be suspected in patients with watery diarrhea, especially in coastal areas.
Determination of cellular fatty acid compositions of various yeasts by gas-liquid chromatography
Authors: Moss C W , Shinoda T , Samuels J W
Published: January 2020

The cellular fatty acid composition of 51 cultures of various species of yeasts was determined by gas-liquid chromatography. Analysis was done with a fused-silica gas-liquid chromatography capillary column, with resolution of all components including mono-, di-, and tri-unsaturated 18-carbon acids. The cultures were placed into one of four distinct gas-liquid chromatography groups on the basis of large quantitative differences in fatty acids. Group I contained only Saccharomyces species and group II only Torulopsis glabrata. Most Candida species were placed into group III, and group IV contained only basidiomycetous yeasts.
Automated identification of gram-positive bacteria
Authors: Ruoff K L , Ferraro M J , Jerz M E , Kissling J
Published: January 2020

A total of 451 strains of gram-positive bacteria were identified with a prototype of the Gram-Positive Identification card used in conjunction with the AutoMicrobic system (Vitek Systems, Inc., Hazelwood, Mo.). Of the species that the Gram-Positive Identification card is capable of identifying, 85% of staphylococcal, 50% of beta-hemolytic group A, B, C, F, and G streptococcal, 91% of group D streptococcal, 100% of pneumococcal, 63% of viridans streptococcal, and 100% of Listeria monocytogenes strains tested displayed Gram-Positive Identification card identifications that were in agreement with identifications obtained by conventional methods.
Investigation of an outbreak of antibiotic-associated colitis by various typing methods
Authors: Wüst J , Sullivan N M , Hardegger U , Wilkins T D
Published: January 2020

During an outbreak of diarrheal disease due to Clostridium difficile in a surgical ward, 16 C. difficile isolates were cultured from fecal samples of 15 patients. Agarose gel electrophoresis for the detection of plasmid DNA, crossed immunoelectrophoresis for the detection of extracellular antigens and toxins, polyacrylamide gel electrophoresis for analyses of soluble proteins, assays for cytotoxicity, and a comparison of susceptibility to antimicrobial agents were employed. At least 12 of the 16 isolates were shown to be phenotypically the same strain. These findings suggest that in a hospital setting, diarrhea and pseudomembranous colitis caused by C. difficile can be of nosocomial origin and that they can spread from patient to patient.
Failure to recover alpha-hemolytic streptococci or malignancy-associated microorganisms from patients with kidney disease and from healthy humans
Authors: Zierdt C H , Hasbargen J , Copley J B
Published: January 2020

We duplicated blood culture techniques and media used by workers reporting alpha-hemolytic streptococci from nephropathy patients as well as from healthy persons. We studied 33 kidney patients presenting 12 diagnosed kidney diseases. The study was expanded to duplicate the experimental blood culture techniques of workers who reported Bacillus licheniformis and Cryptocides tumefaciens from patients with malignancies and, to a lesser degree, from healthy people. Seven culture media and 21 conditions of growth were used. There were no streptococcal isolates, and the few random isolates of other bacteria indicated that they were contaminants. Thus, our study did not corroborate the previous reports.
Improved method for testing susceptibility of Mycobacterium tuberculosis to pyrazinamide
Authors: Butler W R , Kilburn J O
Published: January 2020

The acid medium required to test susceptibility of Mycobacterium tuberculosis to pyrazinamide (PZA) is a major problem in obtaining reliable test results. Satisfactory growth is usually obtained on Middlebrook and Cohn 7H10 medium at pH 5.5 if albumin-dextrose-catalase (ADC) supplement rather than oleic acid-albumin-dextrose-catalase is used; however, some lots of ADC supplement still fail to support growth at this low pH. A rapid turbidimetric test was developed to determine the growth-supporting potential of ADC enrichment for M. tuberculosis at pH 5.5. An atmosphere supplemented with 5 to 10% carbon dioxide, used to stimulate growth of tubercle bacilli on 7H10 medium, counteracted the growth-inhibiting effects of PZA. By using optimum conditions of medium and pH, the susceptibility of 90% of M. tuberculosis strains to PZA was determined.
Demonstration of age-dependent capsular material on Pasteurella haemolytica serotype 1
Authors: Corstvet R E , Gentry M J , Newman P R , Rummage J A , Confer A W
Published: January 2020

Extracellular capsular material was demonstrated on early log-phase cells of Pasteurella haemolytica serotype 1 by the fluorescent-antibody and several capsular staining techniques. The presence of this material was shown to be age dependent. Wide capsules were demonstrable on cells from 2- to 12-h cultures, whereas cells from 16- to 22-h cultures had very little cell-associated capsular material. The Maneval technique most clearly demonstrated the presence of capsules on cells from young (6-h) cultures when compared with other capsule staining techniques.
Long-wave UV light fluorescence for identification of black-pigmented Bacteroides spp
Authors: Slots J , Reynolds H S
Published: January 2020

Black-pigmented Bacteroides strains were grown on blood agar, and the colonies were evaluated for fluorescence from long-wave UV light. Most test strains of Bacteroides melaninogenicus subsp. intermedius exhibited a brilliant red fluorescence. B. melaninogenicus subsp. melaninogenicus fluoresced mostly red-orange. Bacteroides asaccharolyticus showed a yellow or red fluorescence. The intensity of the Bacteroides fluorescence weakened when the black pigment of the colonies developed. In contrast, neither young nor old colonies of the oral species Bacteroides gingivalis displayed fluorescence. Since B. gingivalis can produce severe oral infections and also can seed to nonoral sites, awareness of the inability of this organism to fluoresce is important for microbiologists utilizing UV light fluorescence to screen for black-pigmented Bacteroides spp. The present data also indicate that UV light fluorescence may be a rapid method of distinguishing some black-pigmented Bacteroides spp.
Methods for distinguishing gram-positive from gram-negative bacteria
Authors: Carlone G M , Valadez M J , Pickett M J
Published: January 2020

Lysis by KOH and hydrolysis of L-alanine-4-nitroanilide were compared with the Gram reaction of aerobic, microaerophilic, and anaerobic bacteria. Both tests correlated well with the Gram reaction with nonfermentative bacilli and Bacillus species, whereas they did not correlate with nonsporulating anaerobes. Only campylobacteria were KOH positive and L-alanine-4-nitroanilide and gram negative.
Thymidine plaque autoradiography of thymidine kinase-positive and thymidine kinase-negative herpesviruses
Authors: Tenser R B , Jones J C , Ressel S J , Fralish F A
Published: January 2020

Plaques formed by herpes simplex virus (HSV), pseudorabies virus, and varicella-zoster virus were studied by plaque autoradiography after [14C]thymidine labeling. Standard thymidine kinase-positive (TK+) viruses and TK- mutants of HSV types 1 and 2 and pseudorabies virus were studied, including cell cultured viruses and viruses isolated from animals. Autoradiography was performed with X-ray film with an exposure time of 5 days. After development of films, TK+ plaques showed dark rims due to isotope incorporation, whereas TK- plaques were minimally labeled. Plaque autoradiography of stock TK- viruses showed reversion frequencies to the TK+ phenotype of less than 10(-3). Autoradiography indicated that TK- virus retained the TK- phenotype after replication in vivo. In addition, it was shown that TK- HSV could be isolated from mouse trigeminal ganglion tissue after corneal inoculation of TK- HSV together with TK+ HSV. The plaque autoradiographic procedure was very useful to evaluate proportions of TK+ and TK- virus present in TK+-TK- virus mixtures.
Virulence and phenotypic characterization of Yersinia enterocolitica isolated from humans in the United States
Authors: Kay B A , Wachsmuth K , Gemski P , Feeley J C , Quan T J , Brenner D J
Published: January 2020

Yersinia enterocolitica was recently reclassified into Yersinia enterocolitica sensu stricto and three additional species. With this new classification, it was of interest to reexamine pathogenicity previously ascribed to Y. enterocolitica. All available clinical isolates of Y. enterocolitica sent to the Centers for Disease Control from 1970 through 1980 were selected for characterization and comparison. One-hundred such strains had been submitted, from 21 states. Most (85%) were biotype 1, and O:8 was the most common of the 24 serotypes encountered. All strains were examined by several virulence assays. Two strains caused conjunctivitis in guinea pigs, 7 were lethal for mice, 54 invaded HEp2 cells, 18 produced a heat-stable enterotoxin, 9 were calcium dependent, 20 autoagglutinated, and 34 had a distinctive colonial morphology at 37 degrees C. Ten isolates of each of the new species that had previously been grouped with Y. enterocolitica (Y. kristensenii, Y. intermedia, and Y. frederiksenii) were characterized and were generally negative in all assays. This study points out pathogenicity differences among Yersinia species, confirms the complex nature of virulence in Y. enterocolitica, and confirms that no single current assay correlates with virulence in Y. enterocolitica.
Septic arthritis caused by Kingella kingae
Authors: Gay R M , Lane T W , Keller D C
Published: January 2020

A normal part of the oral flora, Kingella kingae has seldom been recognized as the cause of serious clinical infections. We report a case of documented septic arthritis caused by K. kingae in an otherwise healthy infant. We suggest that it may be more common than thought based on the general unfamiliarity with this organism and the fact that several dozen clinical isolates have been identified by reference laboratories.
Micronitrous acid extraction-coagglutination test for rapid diagnosis of streptococcal pharyngitis
Authors: Gerber M A
Published: January 2020

A micronitrous acid extraction-coagglutination test for the rapid diagnosis of streptococcal pharyngitis was examined in a busy pediatric clinic and found to be a simple, rapid, and inexpensive procedure with a sensitivity of 78% and a specificity of 98% when compared with blood agar culturing.
Solid-phase enzyme immunoassay for Chlamydial antibodies
Authors: Saikku P , Paavonen J , Väänänen P , Vaheri A
Published: January 2020

An enzyme immunoassay (EIA) for chlamydial immunoglobulin G antibodies was developed by using microtiter wells coated with partially purified reticulate bodies of Chlamydia trachomatis serotype L2, grown in McCoy cells, and uninfected McCoy cells as a control. Duplicate testing of a single serum dilution, 1:500, was found to be sufficient. A good correlation between positive reactions was observed in a comparative study of 421 patient sera with the EIA and an inclusion immunofluorescence test. A good correlation between positive reactions was also observed in a comparative study of 140 patient sera with EIA and microimmunofluorescence tests in which chlamydial elementary or reticulate bodies were used as antigens. Sera of 77 healthy control individuals with low titers in inclusion immunofluorescence or complement fixation tests gave negative results in the EIA. Immunoblotting experiments showed that the major antigenic component in the EIA antigen was a protein with an Mr of 39,000.
Differentiation between spores of Bacillus anthracis and Bacillus cereus by a quantitative immunofluorescence technique
Authors: Phillips A P , Martin K L , Broster M G
Published: January 2020

A quantitative immunofluorescence assay based on fiber optic microscopy was used to measure the reaction of formalized spores of Bacillus anthracis and Bacillus cereus isolates with fluorescein conjugates prepared by hyperimmunization with B. anthracis Vollum spores. The spores of 11 of the 20 B. cereus strains reacted with the anti-anthrax conjugate to such an extent that they were indistinguishable from the spores of the several B. anthracis isolates tested. However, absorption of the conjugate with spores of B. cereus NCTC 8035 and B. cereus NCTC 10320 greatly reduced the cross-reaction with the B. cereus preparations so that the mean specific fluorescence of samples of B. cereus spores was in no case higher than 14% of the fluorescence of a reference B. anthracis Vollum preparation.
Rapid Latex Agglutination Test for Rubella Antibody
Authors: Sever John L. , Tzan Nancy R. , Shekarchi Isabel C. , Madden David L.
Published: January 2020

The latex agglutination card test (Rubascan) for the detection of rubella antibody was compared with the standard hemagglutination inhibition and enzyme-linked immunosorbent assay tests. There was complete agreement with sera which had hemagglutination inhibition titers of ≥16. Sera with low levels of antibody which were positive in the enzyme-linked immunosorbent assay, however, gave negative latex agglutination results approximately 25% of the time (false negatives), whereas sera which were negative in the enzyme-linked immunosorbent assay gave false-positive results in about 3% of the cases. The use of capillary “finger stick” plasma instead of venous sera resulted in additional false-negative latex agglutination tests among patients with very low antibody titers. Because of the simplicity of the method, it should be possible to use this test in physicians' offices and in large immunization campaigns. Care should be taken to become completely familiar with the procedures and reading of the agglutination patterns. Control sera should always be used. Interpretation of results should take into consideration the rates of false-negative and false-positive results noted above. These rates apply to sera with little or no antibody. In particular, negative tests should be confirmed with more specific methods in critical cases, such as pregnant women exposed to rubella or women of childbearing age who are being considered for immunization. There was no problem with the latex agglutination findings for sera with higher titers. Since results are available in 8 min, physicians should be able to counsel their patients rapidly and immunize, if necessary, while the patient is still present.
Cephalexin-supplemented Jones-Kendrick charcoal agar for selective isolation of Bordetella pertussis: comparison with previously described media
Authors: Stauffer L R , Brown D R , Sandstrom R E
Published: January 2020

Four agar media, Jones-Kendrick (JK) charcoal agar unsupplemented, JK agar supplemented with 0.5 U of penicillin per ml, JK medium supplemented with 2.5 micrograms of methicillin per ml, and JK medium supplemented with 40 micrograms of cephalexin per ml, were evaluated to determine their ability to support growth of Bordetella pertussis, their ability to selectively inhibit normal pharyngeal flora while maintaining growth of B. pertussis, and their stability during storage. Five stock cultures of B. pertussis were plated on each of the media. Penicillin- and cephalexin-supplemented media were more inhibitory for early growth of B. pertussis than was medium supplemented with methicillin. However, after 5 days of incubation at 35 degrees C, all media supported good growth of this organism. When employed to detect B. pertussis in sham specimens, prepared by mixing normal pharyngeal material with each of the five B. pertussis stock cultures, the medium containing cephalexin was judged superior to all other media tested in its combined ability to suppress the growth of normal pharyngeal flora and to allow early detection of Bordetella colonies. All media tested retained their efficacy after 9 weeks of storage at 2 to 8 degrees C.
Current trends of Yersinia enterocolitica isolates in the New York City area
Authors: Bottone E J
Published: January 2020

During an 8.5-year period (1974 to 1982), 56 Yersinia enterocolitica isolates from patients residing mainly in the New York City area were studied. Evaluation of these isolates revealed a marked increase in bacteremic episodes caused by strains of serogroups of O:3 and O:5,27 and the overall emergence of serogroup O:3, biotype 4, phage type 9b Y. enterocolitica. Of the serogroup O:3 stool isolates, 59% (19/32) were recovered from patients in their first year of life. One of these subjects had concurrent serogroup O:3 bacteremia. The apparent establishment of serogroup O:3 Y. enterocolitica in urban communities raises the potential for widespread outbreaks of disease caused by these strains.
Characteristics of pathogenic Neisseria spp. isolated from homosexual men
Authors: Janda W M , Morello J A , Lerner S A , Bohnhoff M
Published: January 2020

Oropharyngeal, urethral, and rectal cultures for pathogenic Neisseria spp. were collected from 815 homosexual men attending a community clinic in Chicago. Meningococci were characterized by serogrouping and antimicrobial susceptibility testing. Gonococci were auxotyped, and susceptibilities to penicillin and tetracycline were determined. Of the 815 men tested, 42.5% carried meningococci in the oropharynx. Gonococci were recovered from the urethra, rectum, and oropharynx of 18.5, 16.3, and 5.6%, respectively. Meningococci were also recovered from the urethra (6 patients) and the rectum (15 patients). Some of these isolates were identical to the isolates from the oropharynges of the same patients, whereas others were distinct from the oropharyngeal isolates by serogroup or antimicrobial susceptibilities. Serogroups B, W135, and C comprised over 90% of the meningococci. Almost 80% of the gonococcal strains required minimal inhibitory concentrations greater than 0.06 micrograms of penicillin per ml, whereas greater than 90% of the meningococci were inhibited at this concentration. Auxotyping demonstrated three major auxotypes: Zero (required none of the nutrients tested), 60%; arginine requiring, 19.4%; and proline requiring, 12.3%. Only four strains (1.2%) required arginine, hypoxanthine, and uracil.
Evaluation of the cefonicid disk test criteria, including disk quality control guidelines
Authors: Barry A L , Jones R N , Thornsberry C
Published: January 2020

Cefonicid (SKF 75073) is a second-generation cephalosporin which has a spectrum of antimicrobial activity similar to that of cefamandole, but cefoxitin (a cephamycin) and cephalothin have uniquely different spectra of activity. The second-generation cephalosporins tested displayed comparable susceptibility to beta-lactamases and inhibited type I beta-lactamases. Although cefonicid has a longer serum half-life (3 to 4 h) compared with the currently used drugs, the same minimal inhibitory concentration breakpoints separating susceptible and resistant categories were applied to tests with cefonicid, cefamandole, and cephalothin. Regression analysis of the disk diffusion test results confirmed the use of identical zone size breakpoints for 30-micrograms cefonicid, cefamandole, and cephalothin disks: all three produced similar parabolic regression lines. Further analysis of disk test data confirmed the fact that cefonicid and cefamandole disks might be used interchangeably. But for routine tests, cefonicid disks might be preferred in order to minimize the number of very major (false-susceptible) interpretive errors. Suggested cefonicid 30-micrograms disk interpretive criteria are: susceptible, greater than or equal to 18 mm (less than or equal to 8.0 micrograms/ml), and resistant, less than or equal to 14 mm (greater than 16 micrograms/ml). Quality control zone diameter limits were calculated from data obtained in a multilaboratory collaborative study.
Fluorescent Treponemal Antibody Absorption Double-Staining Test Evaluation
Authors: Farshy Carol E. , Kennedy Edward J. , Hunter Elizabeth F. , Larsen Sandra A.
Published: January 2020

The fluorescent treponemal antibody absorption (FTA-ABS) double-staining (DS) test has been developed for microscopes equipped with incident illumination, and the procedure offers many advantages over the FTA-ABS test when tests are performed with this equipment. In this study, 346 fresh sera, including 35 from patients with syphilis, were evaluated by the FTA-ABS DS test. Parameters for investigation included two readers, each using a different microscope; a new FTA-ABS DS test reporting system; sera heated at 56°C for 30 min versus unheated sera; and sera retested after at least 2 weeks of freezer storage. Agreement for FTA-ABS DS test readings between the two microscopes was 99%. Between-test agreement for the FTA-ABS test with the conventional reporting system and the FTA-ABS DS test with the new reporting system was 95%. Sensitivity calculations based on reactivity for the 35 syphilis sera were 94% for the FTA-ABS DS test and 91% for the FTA-ABS test. Specificity calculations based on non-reactivity of nonsyphilis sera were 98% for the FTA-ABS DS test and 93% for the FTA-ABS test. Differences in percentages appeared to be related to borderline readings in the FTA-ABS test. For example, if the same reporting system was used for the reference FTA-ABS test, the specificity was 97%. When sera were examined within 48 h, no difference was observed in results obtained with heated and unheated sera. Sera frozen for 2 weeks showed comparable results in the FTA-ABS DS test and the FTA-ABS test. These findings strongly support the recommendation that the FTA-ABS DS test be accepted as a confirmatory test for syphilis. The new reporting system for the FTA-ABS DS test would be advantageous for the reference FTA-ABS procedure.
Diagnosis of bacterial pulmonary infections with quantitative protected catheter cultures obtained during bronchoscopy
Authors: Pollock H M , Hawkins E L , Bonner J R , Sparkman T , Bass J B
Published: January 2020

Quantitative bacteriology was performed on specimens collected by protected catheter fiberoptic bronchoscopy from 172 patients. Of the patients who had pneumonia, 75 of 78 (96%) had one or more species present at greater than or equal to 10(3) CFU/ml, whereas 2 of 35 (6%) control patients had organisms present in that quantity. In addition, 66% of the control specimens yielded no isolates by this technique. All of the 11 patients with bronchitis had greater than or equal to 10(3) CFU/ml. Quantitative bacteriology revealed high levels of colonization in patients without infection and endobronchial structural disease. The data suggest that bacterial counts of greater than or equal to 10(3) CFU/ml in suspended secretions collected with a protected catheter brush were diagnostic of the bacteriological etiology of lower respiratory tract infections in patients without endobronchial structural abnormalities.
Deficient spontaneous cell-mediated cytotoxicity and lectin-induced cellular cytotoxicity by peripheral blood mononuclear cells from Thai adults naturally infected with malaria
Authors: Gilbreath M J , Pavanand K , MacDermott R P , Phisphumvithi P , Permpanich B , Wimonwattrawatee T
Published: January 2020

To assess general cytotoxic effector cell capabilities by peripheral blood mononuclear cells from patients with active malaria infections, we examined antibody-dependent cellular cytotoxicity, spontaneous cell-mediated cytotoxicity, and lectin-induced cellular cytotoxicity by using human and chicken erythrocyte, Chang cell line, and K562 cell line targets. By using human erythrocyte and Change cell line targets, we found that Thai adults naturally infected with malaria had significantly impaired lectin-induced cellular cytotoxicity. In addition, spontaneous cell-mediated cytotoxicity was deficient with K562 but not with Chang cell line targets. Finally, no change in antibody-dependent cellular cytotoxicity was observed when chicken erythrocyte or Chang cell line targets were used. These observations, coupled with our previous observations of a physical loss of peripheral blood T cells, the presence of lymphocytotoxic serum antibodies, and defective T suppressor cell generation in patients with malaria, indicate that major alterations in the cellular immune system occur in patients with active malaria infections.
Sensitive Enzyme Immunoassay with β-
d
-Galactosidase—Fab Conjugate for Detection of Type A Influenza Virus Antigen in Clinical Specimens
Authors: Harmon Maurice W. , Russo Lorrie L. , Wilson Samuel Z.
Published: January 2020

The most sensitive method for diagnosis of type A influenza virus infection is isolation of the agent in cell culture. However, detection and identification may require several days to complete. This delay in diagnosis prevents effective use of the antiviral agents available for treatment of type A influenza infection. As a rapid diagnostic method, enzyme immunoassay (EIA) is attaining increased usage for direct detection of viral antigen in clinical specimens. Standard EIA techniques, however, are usually not sensitive enough for reliable detection of viral antigen in respiratory secretions. We developed a conjugate consisting of the antigen-binding fragment of goat antirabbit immunoglobulin G coupled to β-
d
-galactosidase, using the heterobifunctional reagent
N
-succinimidyl 3-(2-pyridyldithio)propionate. Other immunoreagents in our EIA consisted of guinea pig and rabbit antisera to influenza A/Brazil/11/78 (H1N1) for microtiter plate coating and primary antiserum, respectively. The sensitivity of this EIA was tested with 60 clinical specimens containing influenza A/England/333/80 (H1N1) which closely resembles A/Brazil. Of 31 initial specimens, collected within 24 h of the onset of symptoms, 27 (87%) were positive, using a fluorgenic substrate, and 18 of 29 (62%) specimens obtained 12 to 60 h after the initial specimens were positive, for a total of 75% (45 of 60). All positive reactions were specific, as shown in a confirmatory test with preimmune and hyperimmune guinea pig globulins. Clinical specimens negative for virus (
n
= 33) or containing heterologous respiratory viruses (
n
= 26) were negative in this system. These results indicate that EIA systems can be developed with a sensitivity approaching that required for clinical usefulness.
Potential spectrum of etiological agents of viral enteritis in hospitalized infants
Authors: Riepenhoff-Talty M , Saif L J , Barrett H J , Suzuki H , Ogra P L
Published: January 2020

Fecal specimens were obtained from 1,160 infants and young children with acute nonbacterial gastroenteritis over a period of 2 years. A total of 100 specimens were obtained from age-matched asymptomatic controls. The specimens were examined for the presence of viruses by electron microscopy. Viruses or virus-like particles frequently associated with enteritis were detected in 27% (314 of 1,160) of the symptomatic patients. No viruses or virus-like particles were detected in the 100 control subjects. Rotavirus was detected in 73% (230 of 314) of the virus-positive samples. The mean age of rotavirus-positive patients was 11.5 months, although the patients ranged in age from 2 weeks to 5 years. Of the symptomatic patients, 45 (14%) exhibited small virus-like particles (15 to 40 nm) in the feces in the absence of any other detectable pathogen. Some of the virus-like particles observed in these patients appeared to be similar to astrovirus, and some appeared to be similar to the Otofuke agent or possibly minireovirus. Significantly, however, the mean age of infants with enteritis from whom these small virus-like particles were recovered was 4.5 months (range, 10 days to 19 months). Our findings confirmed the already-known fact that rotaviruses constitute the most important cause of viral enteritis in young children. In addition, small viruses may be an important cause of gastroenteritis in infants under 5 months of age.
Identification of Legionella pneumophila by latex agglutination
Authors: Sedgwick A K , Tilton R C
Published: January 2020

A latex agglutination test for the identification of Legionella pneumophila serogroups 1 through 6 is described. The reagent is specific for L. pneumophila and enables the ready identification of L. pneumophila colonies on agar plates. Preliminary evidence suggests that latex agglutination enables the detection of soluble L. pneumophila antigens in respiratory secretions of patients suspected of having legionellosis.
Immunofluorescence staining of adenovirus in fixed tissues pretreated with trypsin
Authors: Chandler F W , Gorelkin L
Published: January 2020

We describe an immunofluorescence staining procedure for adenovirus in Formalin-fixed, paraffin-embedded tissue sections pretreated with a 0.25% trypsin solution. In trypsinized tissue sections stained with fluorescein-labeled antibody to adenovirus, viral antigen was brightly fluorescent and easily detected each time specimens were processed, and the nonspecific background fluorescence was always minimal. Viral antigen was nonfluorescent or only weakly fluorescent in tissue sections not pretreated with trypsin. Because pathology laboratories usually receive Formalin-fixed tissues for examination, this rapid and practical procedure can be routinely used to extend the diagnostic capability of conventional histopathology.
Streptococcus equisimilis Pneumonia in a compromised host
Authors: Siefkin A D , Peterson D L , Hansen B
Published: January 2020

A fatal case of Streptococcus equisimilis pneumonia and septicemia is described in a young man with Hodgkin's disease. The disease course consisted of exudative pharyngitis, macular rash, septic shock, disseminated intravascular coagulation, deep vein thrombosis, and pulmonary embolization. S. equisimilis was isolated from blood, throat, and sputum cultures antemortem and from lung cultures at autopsy.
Preservation of tissue specimens during transport to mycobacteriology laboratories
Authors: Richards W D , Wright H S
Published: January 2020

Chloramine-T and sodium borate solutions were evaluated for their effectiveness in preserving Mycobacterium bovis and controlling the growth of non-mycobacterial contaminants on tissue specimens during transport to laboratories. The number of culturable M. bovis cells in suspension was reduced by 5.1 log10 upon exposure to chloramine-T solution and by less than 1 log10 upon exposure to sodium borate solution for 7 days. Reinoculation of laboratory media (because of overgrowth by non-mycobacterial contaminants) was required for 52.6% of 190 routine bovine tissue specimens shipped refrigerated in chloramine-T solution and for 6.1% of 520 specimens shipped unrefrigerated in sodium borate solution. M. bovis was isolated from bovine tissue stored in sodium borate solution at 23 degrees C for 17 weeks and at 4 degrees C for 25 weeks. Unrefrigerated sodium borate solution has been used successfully to ship tissue specimens to our laboratory for the past 11 years.
Probe colorimeter for quantitating enzyme-linked immunosorbent assays and other colorimetric assays performed with microplates
Authors: Ackerman S B , Kelley E A
Published: January 2020

The performance of a fiberoptic probe colorimeter (model PC800; Brinkmann Instruments, Inc., Westbury, N.Y.) for quantitating enzymatic or colorimetric assays in 96-well microtiter plates was compared with the performances of a spectrophotometer (model 240; Gilford Instrument Laboratories, Inc., Oberlin, Ohio) and a commercially available enzyme immunoassay reader (model MR590; Dynatech Laboratories, Inc., Alexandria, Va.). Alkaline phosphatase-p-nitrophenyl phosphate in 3 M NaOH was used as the chromophore source. Six types of plates were evaluated for use with the probe colorimeter; they generated reproducibility values (100% coefficient of variation) ranging from 91 to 98% when one individual made 24 independent measurements on the same dilution of chromophore on each plate. Eleven individuals each performed 24 measurements with the colorimeter on either a visually light (absorbance of 0.10 at 420 nm) or a dark (absorbance of 0.80 at 420 nm) dilution of chromophore; reproducibilities averaged 87% for the light dilution and 97% for the dark dilution. When one individual measured the same chromophore sample at least 20 times in the colorimeter, in the spectrophotometer or in the enzyme immunoassay reader, reproducibility for each instrument was greater than 99%. Measurements of a dilution series of chromophore in a fixed volume indicated that the optical responses of each instrument were linear in a range of 0.05 to 1.10 absorbance units.