bluuebunny/crossref_metadata_2025 huggingface dataset:
Neutralization of the inhibitory effect of sodium polyanetholesulfonate on Neisseria meningitidis in blood cultures processed with the Du Pont Isolator System
Authors: Scribner R K , Welch D F
Published: January 2020

The inhibitory and bactericidal effects of sodium polyanetholesulfonate on Neisseria meningitidis were neutralized by blood lysis which occurs within the pediatric Isolator 1.5 Microbial tube (E. I. du Pont de Nemours & Co., Inc., Wilmington, Del.). Lysed blood was more effective than 2.5% gelatin in preventing the inhibitory effect. All but 1 of 16 N. meningitidis strains were killed by 0.06% sodium polyanetholesulfonate in the absence of lysed blood, whereas none were killed by 1.0% sodium polyanetholesulfonate when lysed blood was present. The possible clinical relevance of these results was reflected in the improved detection of meningococcemia in children when the Isolator 1.5 Microbial tube was compared with a conventional broth system.
Production of toxic-shock-associated protein(s) in Staphylococcus aureus strains isolated from 1956 through 1982
Authors: Hayes P S , Graves L M , Feeley J C , Hancock G A , Cohen M L , Reingold A L , Broome C V , Hightower A W
Published: January 2020

A total of 281 Staphylococcus aureus strains selected from those submitted to the Centers for Disease Control for phage typing between 1956 and 1982 were tested for the production of toxic-shock-associated protein (TSAP) by isoelectric focusing (IEF) and solid-phase radioimmunoassay. The results suggest that the observed temporal trends in the incidence of toxic-shock syndrome were not primarily due to changes in the distribution of TSAP-positive strains of S. aureus. Overall, 39 (14%) were TSAP positive by both methods. The earliest positive strain was an isolate submitted in 1957. TSAP-positive strains were most prevalent in the group of isolates submitted in 1976 for which 29% reacted, but the percent positive subsequently declined for isolates submitted in later years. TSAP production was more frequent among strains of phage types 29, 29/52, and 52 than among other strains. The use of IEF to identify TSAP detected false-positive proteins. Seven strains were positive by IEF and negative by solid-phase radioimmunoassay, whereas only one was positive by solid-phase radioimmunoassay and negative by IEF.
Evaluation of a microtiter system for identification of anaerobic bacteria
Authors: Savuto P S , Ellner P D
Published: January 2020

The Anaerobe Combo Panel (American MicroScan, Mahwah, N.J.) was evaluated for its ability to identify anaerobic bacteria. The frozen, 96-well panel utilizes 24 biochemical reactions and four antimicrobial agents for species identification. The Anaerobe Combo Panel was used to test 114 clinical isolates of strict anaerobes. Reactions were read after 48 h, and the results were compared with those obtained with the PRAS II system (Scott Laboratories, Inc., Fiskeville, R.I.). Discrepancies between the two systems were resolved by gas-liquid chromatography. With the Anaerobe Combo Panel, 84% of the organisms were able to grow, and 89% of these were correctly identified to genus level and 78% to species level. The Anaerobe Combo Panel was easy to inoculate and read, but some of the reactions were difficult to interpret, and not all of the derived codes were found in the code book.
Proposed revision of the Wauters et al. antigenic scheme for serotyping of Yersinia enterocolitica
Authors: Aleksić S , Bockemühl J
Published: January 2020

The antigenic scheme of Wauters and co-workers was applied to serotype a total of 585 strains of Yersinia enterocolitica, 43 strains of Yersinia kristensenii, 40 strains of Yersinia frederiksenii, and 25 strains of Yersinia intermedia. The O antigens 11,23; 11,24; 12,25; 12,26; and 28 were exclusively associated with Y. kristensenii. O antigen 16 was associated with Y. kristensenii and Y. frederiksenii. The serogroups O:4,33 and O:17 were only found in Y. intermedia, whereas the remaining serogroups were associated with Y. enterocolitica. The O antigen 34 proved to be identical with O:10; O factor 29 was poorly expressed and is suggested to be excluded from the list of recognized antigens. As sera of O factors 1, 2a, and 2b of Y. enterocolitica are difficult to prepare, we propose to combine the serogroups O:1,2a,3 and O:2a,2b,3 with O group 3. The H antigens l, r, s, and t were characteristic of Y. kristensenii, whereas H:p was exclusively found in Y. frederiksenii. H:q belonged to Y. intermedia, whereas H:o occurred in Y. kristensenii, Y. frederiksenii, and Y. intermedia. The remaining H factors a to k, m, and n occurred in Y. enterocolitica in various combinations. Up to 15 different combinations of H antigen factors were identified in a single serogroup of Y. enterocolitica. We propose the definition of a new H antigen, u. We suggest the exclusion from the typing scheme of those O and H antigens which are not associated with Y. enterocolitica. For O typing, we present a revised antigenic scheme of Y. enterocolitica with 18 serogroups containing 20 O factors. We emphasize the necessity of its continuous usage, taking into account the international situation.
Characterization of antibody inhibiting adherence of Bordetella pertussis to human respiratory epithelial cells
Authors: Tuomanen E I , Zapiain L A , Galvan P , Hewlett E L
Published: January 2020

We have recently established the topographic specificity of the adherence of Bordetella pertussis to human ciliated respiratory epithelial cells. For this study, we employed the same quantitative, immunofluorescent adherence assay to test the possibility that sera of patients recovering from naturally acquired whooping cough or immunized with pertussis vaccine may contain activity capable of interfering with this specific adherence. Evaluation of paired sera from six children with culture-proven pertussis demonstrated that antiadherence activity appeared in serum during convalescence from disease. Nine children immunized with diptheria-pertussin-tetanus vaccine also showed activity against adherence, although it was significantly less than in those with clinical disease. Naturally acquired serum antiadherence activity was identified in both immunoglobulin G (IgG) and IgA antibody classes, whereas, as expected, only IgG antibody was present in children receiving the parenteral vaccine. The findings suggest that natural infection or vaccination are associated with the acquisition of serum activity inhibiting the adherence of B. pertussis to ciliated cells. Immunization may fail to elicit IgA antiadherence activity.
Antigenic characterization of human coronaviruses 229E and OC43 by enzyme-linked immunosorbent assay
Authors: Schmidt O W
Published: January 2020

Human coronaviruses 229E and OC43 possess three distinct antigens each which are located in peplomer, membrane, and nucleoprotein virion subcomponents. Although specific antigens are associated with similar polypeptides in both viruses, neither shared antigens nor serological cross-reactions have been observed. These findings were confirmed by enzyme-linked immunosorbent assay; rabbit whole-virus-specific antisera reacted with dissociated homologous virus and each of its subcomponents, whereas antisera monospecific to separate subcomponents (peplomers, membrane, or core) recognized only their respective components. Since neither shared antigens nor serological cross-reactions were seen between the two viruses, the specificity of the assay was similar to that of crossed-immunoelectrophoresis, virus neutralization, and complement fixation assays. However, sensitivity was increased at least 1,000-fold; complement fixation antibody titers of 2,000 corresponded to enzyme-linked immunosorbent assay titers of 3,200,000. Similar results were obtained with human convalescent-phase sera. In addition, the most prevalent human antibodies were found to be directed against virion peplomers. However, specific antibodies to core antigens and lesser amounts to membrane antigens were found in the sera of patients, which showed significant antibody rises when purified virion subcomponents were used as antigens. Importantly, rises and declines in titers of antibody to one virus and its specific antigens were independent from levels of titers of antibody to the other virus.
Comparison of an indirect fluorescent-antibody test with an enzyme-linked immunosorbent assay for serological studies of Lyme disease
Authors: Magnarelli L A , Meegan J M , Anderson J F , Chappell W A
Published: January 2020

An enzyme-linked immunosorbent assay was compared with an indirect fluorescent antibody test for its ability to detect antibodies to the Lyme disease spirochete in sera of naturally infected humans, dogs, and white-footed mice and experimentally infected Swiss mice. Ninety-five percent of the total 123 sera analyzed reacted similarly in both tests. For 36 human sera, the correlation coefficient (r = 0.47) for logarithmic transformations of indirect fluorescent antibody and enzyme-linked immunosorbent assay titers was significant at P less than 0.01. Within each mammalian species, mean titers for indirect fluorescent antibody and enzyme-linked immunosorbent assay antibodies were within three-fold. Comparisons of different naturally infected mammals revealed relatively higher average titration endpoints in both tests for patients with Lyme disease. Human sera also had the widest range of titers. Both methods proved satisfactory for serological confirmation of prior spirochetal infections.
Bacterial growth and killing in chronic ambulatory peritoneal dialysis fluids
Authors: Verbrugh H A , Keane W F , Conroy W E , Peterson P K
Published: January 2020

We determined the ability of Staphylococcus epidermidis, Staphylococcus aureus, and Escherichia coli to survive and grow in peritoneal dialysis fluids from patients undergoing chronic ambulatory peritoneal dialysis. Staphylococci did not survive in commercially available dialysis solutions but grew readily in peritoneal effluents obtained from patients after the dialysis dwell time. The number of CFU doubled 6 and 13 times in 24 h for S. epidermidis and S. aureus, respectively. E. coli grew well in both the pre- and postdialysis peritoneal fluid. Peritoneal macrophages as well as peripheral blood leukocytes inhibited bacterial growth in peritoneal dialysis fluid. However, 10(6) phagocytes per ml were minimally required to obtain a bacteriostatic effect. The addition of serum to peritoneal dialysis fluid increased the antibacterial activity of macrophages and blood leukocytes. The capacity of the aminoglycoside antibiotic tobramycin to reduce bacterial CFU in peritoneal dialysis fluid was only 10% of its bactericidal capacity in standard Mueller-Hinton brush. Peritoneal dialysis fluid had no effect on the antibacterial activity of imipenem.
Identification of Streptococcus bovis and Streptococcus salivarius in clinical laboratories
Authors: Ruoff K L , Ferraro M J , Holden J , Kunz L J
Published: January 2020

Streptococci identified as Streptococcus bovis, S. bovis variant, and Streptococcus salivarius were examined with respect to physiological and serological characteristics and cellular fatty acid content. Similarities in physiological reactions and problems encountered in serological analysis were noted, suggesting that an expanded battery of physiological tests is needed to definitively identify these streptococci. Cellular fatty acid analysis provided an accurate method for distinguishing S. salivarius from S. bovis and S. bovis variant.
Detection of Lassa virus antigens and Lassa virus-specific immunoglobulins G and M by enzyme-linked immunosorbent assay
Authors: Niklasson B S , Jahrling P B , Peters C J
Published: January 2020

Rapid diagnosis of Lassa fever is desirable for the timely therapeutic intervention and implementation of strict quarantine procedures both in West Africa field hospitals where the disease is endemic and at international crossroads. An enzyme-linked immunosorbent assay (ELISA) to measure Lassa virus antigens in viremic sera was developed in which experimentally infected monkeys were used as a model for the human disease. In this test, Lassa virus antigens in test sera were captured in wells of microtiter plates by monkey anti-Lassa virus immunoglobulin. Guinea pig anti-Lassa virus immunoglobulin was then added, and binding of specific immunoglobulin was quantitated by the addition of rabbit anti-guinea pig immunoglobulin followed by alkaline phosphatase-labeled anti-rabbit immunoglobulin. This test detected viremia titers as low as 2.1 log10 PFU/ml in experimentally infected monkey sera, a titer often exceeded in patients with Lassa fever. Inactivation of infectious virus by beta-propiolactone or gamma-irradiation did not diminish reactivity. Antigen-ELISA concentrations increased with infectivity for the first 10 days after infection but then declined while infectivity titers remained high, suggesting that the presence of humoral antibody in viremic sera diminishes the sensitivity of the antigen ELISA. Lassa virus-specific immunoglobulin M (IgM) titers measured in an IgM capture ELISA were detectable within 10 days of infection and peaked after 36 days but remained detectable for 1.5 years. The Lassa virus-specific IgG ELISA response was slightly delayed, peaking on day 73 but declining only slightly thereafter. These studies in a realistic primate model suggest that the antigen detection ELISA or the IgM capture ELISA described, in which beta-propiolactone-inactivated sera are used, should be useful for the rapid diagnosis of human Lassa fever.
Single radial hemolysis test for quantitation of complement-fixing antibodies to non-hemagglutinating viruses
Authors: Fulton R E , DiNinno V L , Frank R I , Fildes J , Turner I J
Published: January 2020

A single radial hemolysis test, which overcomes many of the problems of conventional complement fixation tests, was developed for the quantitation of virus complement-fixing antibodies. The test procedure utilized staphylococcal protein A-coated sheep erythrocytes immobilized in agarose into which antigen was incorporated. Undiluted heat-inactivated serum samples were allowed to diffuse radially from wells punched in the agarose. Protein A served to concentrate the subsequent antigen-antibody reaction on the surface of the erythrocytes. Zones of hemolysis were developed by flooding with complement. With adenovirus as a model, basic test parameters were defined, and optimum reagent concentrations and diffusion conditions were determined. A positive linear relationship was found to exist between zone diameter and increasing log concentration of specific antiserum. No correlation was found between zone diameter and total concentration of immunoglobulin G in test sera. Sera rendered anticomplementary by the addition of carrageenan produced hemolytic zones equal to diameter to those observed with untreated sera. Seventy-seven human sera with known complement fixation titers were tested by this method. Good correlation (r = 0.74) between the complement fixation test and single radial hemolysis was observed. This test was highly reproducible and more sensitive than the conventional complement fixation test.
Rotavirus-specific antibodies in fetal bovine serum and commercial preparations of serum albumin
Authors: Offit P A , Clark H F , Taylor A H , Hess R G , Bachmann P A , Plotkin S A
Published: January 2020

Rotavirus-specific antibodies were detected in fetal bovine serum, bovine serum albumin, and human serum albumin by radioimmunoprecipitation with the NCDV strain of bovine rotavirus as the detecting antigen. Fetal bovine sera neutralized bovine rotavirus in a plaque reduction neutralization test to titers of 1:20 or greater. Immunoglobulins purified from fetal bovine serum by protein A-agarose affinity chromatography precipitated rotavirus antigens but did not neutralize bovine rotavirus. Rotavirus antibodies in fetal bovine serum and in purified serum albumin preparations may interfere with diagnostic assays for the detection of rotavirus antigens or antibodies.
Evaluation of the API latex conjugate reagent for serological typing of Salmonella and Shigella species
Authors: Cleary T J
Published: January 2020

The serological types of Salmonella and Shigella isolates were determined by using the SerImm Sure latex conjugates (Analytab Products, Plainview, N.Y.) and the standard slide agglutination test. The Salmonella latex conjugates correctly typed 114 of the 115 Salmonella isolates found in serogroups A through F; 50% these isolates were from serogroups B. The Shigella latex conjugates correctly typed 87 of the 92 Shigella isolates; 87% of these isolates were from serogroups B and D.
Three-year prospective study of intestinal pathogens in Madrid, Spain
Authors: Velasco A C , Mateos M L , Más G , Pedraza A , Díez M , Gutiérrez A
Published: January 2020

During the period July 1980 through June 1983, in a General Hospital in Madrid, the following organisms were detected from 6,970 patients with gastroenteritis: 710 Salmonella spp. 506 Campylobacter jejuni, 379 Shigella spp., 12 Yersinia enterocolitica, 1,466 rotavirus, 134 Giardia lamblia, and 4 Entamoeba histolytica. Chloramphenicol showed good activity against most tested strains of Salmonella spp., Shigella spp., and C. jejuni. The incidence of Salmonella spp. and Shigella spp. was very marked in the hot dry months of the year, rotavirus predominated during the cold months, and no seasonal variations of importance were seen for C. jejuni and G. lamblia.
C-reactive protein in patients with bacteremia
Authors: McCabe R E , Remington J S
Published: January 2020

Quantitative measurement of C-reactive protein (CRP) in serum has been proposed as a sensitive and, for some populations, a specific indicator of infection. To determine whether early measurement of CRP in serum could differentiate patients with bacteremia from a control group of patients whose blood cultures yielded contaminants, we measured CRP concentrations quantitatively by rate nephelometry in serum samples that had been obtained from patients on the same day as blood samples that yielded bacteria or fungi. Of the 36 episodes of bacteremia, 3 (8.5%) occurred in patients with normal concentrations of CRP in serum and 2 (5.5%) in patients with minimally elevated levels. Of the 21 episodes associated with contaminated blood cultures, only 2 (9.5%) occurred in patients with normal CRP levels. Of the patients with marked elevations of CRP (greater than 10 mg/dl), 18 (86%) had infection, although not all of these patients had bacteremia. We conclude that a normal concentration of CRP in serum does not eliminate the possibility of bacteremia. Moderate elevations (1 to 10 mg/dl) of CRP levels are common in both patients with contaminated blood cultures and in those with bacteremia. If the CRP concentration in serum is greater than 10 mg/dl and if other causes of marked elevations of CRP levels are eliminated, CRP concentration in serum may be a relatively specific indicator of infection. However, elevations of CRP concentrations are neither completely sensitive nor specific for detecting infection in patients with bacteremia.
Diagnosis of fastidious enteric adenoviruses 40 and 41 in stool specimens
Authors: Brown M , Petric M , Middleton P J
Published: January 2020

Thirty-five stool specimens, collected over a 14-week period from pediatric gastroenteritis patients and shown to contain adenovirus by electron microscopy, were inoculated onto 293 and HeLa cells. Virus isolates were characterized by serum neutralization and restriction endonuclease cleavage analysis of viral DNA from infected cells. Adenovirus was isolated upon primary inoculation of 293 cells from all 35 specimens shown to contain adenovirus by electron microscopy. Fastidious adenoviruses 40 and 41 (Ad40 and Ad41) were found in 17 (49%) of the stool specimens, and 4 of these specimens contained a conventional species (Ad1, Ad1, Ad18, Ad31) as well as Ad40. This was first manifest by the observation that four of the isolates which initially grew only in 293 cells acquired the capacity to grow in HeLa cells upon subsequent passage. In each case, the conventional species was undetectable by DNA analysis in the original inoculum but was selected in 293 cells and became the only one detectable by the second passage. Four other specimens, containing Ad1 or Ad31 alone, failed to grow initially in HeLa cells but did grow in 293 cells. The results of this study demonstrate therefore that (i) 293 cells are more sensitive than HeLa cells for the isolation of conventional as well as fastidious enteric adenovirus species and (ii) identification of viruses from patient specimens should involve minimal passage of the virus in cell culture, as a single passage can result in misdiagnosis of the virus associated with the infection.
Bovine rotavirus serotypes and their significance for immunization
Authors: Snodgrass D R , Ojeh C K , Campbell I , Herring A J
Published: January 2020

Neutralization assays on calf fecal rotavirus with antisera to two previously described bovine rotavirus serotypes allowed the isolation of four rotaviruses belonging to a distinct third serotype. In a survey of 85 calf isolates, 80 rotaviruses belonged to serotype 1 (91%), 1 belonged to serotype 2 (1%), and 4 belonged to serotype 3 (5%). Serotypes 1 and 2 were shown to not cross-protect in a passive immunization experiment in gnotobiotic lambs. Ingestion of specific antiserum protected against infection with the homologous, but not heterologous, serotype. Rabbits with no previous exposure to rotavirus responded to sequential vaccination with bovine and human rotavirus serotypes with antibody specific to those serotypes, and the response did not broaden to include serotypes to which they had not been exposed. These factors suggested the need for multivalent rotavirus vaccines. By contrast, 47 adult cows on 11 farms had neutralizing antibodies to two bovine and three human rotavirus serotypes. After vaccination with one bovine rotavirus serotype, these cows produced a significant increase in antibody titers to these same five serotypes but not to two other serotypes to which they had no preexisting antibody. These results were interpreted to indicate that cows will respond heterotypically after monovalent vaccination to all rotavirus serotypes with which they have had experience and, therefore, that single serotype vaccination may be sufficient. This conclusion has practical importance for rotavirus immunization procedures.
Radioimmunofocus assay for detection and quantitation of human rotavirus
Authors: Liu S , Birch C , Coulepis A , Gust I
Published: January 2020

A radioimmunofocus assay suitable for quantitation of cell culture-adapted human rotavirus was developed. The method was reproducible, more sensitive than plaque assay, and useful to detect and quantify strains of rotavirus which do not produce plaques. Preliminary results also suggested that the technique will be a useful means of serotyping cell culture-adapted strains of the virus.
Importance of enteric adenoviruses 40 and 41 in acute gastroenteritis in infants and young children
Authors: Uhnoo I , Wadell G , Svensson L , Johansson M E
Published: January 2020

In a prospective 1-year study of acute infantile gastroenteritis, adenoviruses were detected in the stools or by seroconversions, or both, in 56 of 416 (13.5%) ill children. By use of DNA restriction enzyme analysis, enzyme immunoassay, and culture techniques, 33 of 56 (59%) adenovirus specimens were identified as enteric adenoviruses 40 and 41 (Ad40 and Ad41). They were found as the sole recognizable cause of diarrhea in 30 of 416 (7.2%) ill children and in 0 of 200 controls. Three additional ill children had enteric adenoviruses as a part of a dual infection. Evidence for established adenoviruses (Ad1 through Ad39) in gastroenteritis was found in 15 of 416 (3.6%) ill children but also in 3 of 200 (1.5%) controls. Eight adenovirus specimens remained untyped. Seroconversions were demonstrated in 17 of 18 (94%) paired serum samples from patients shedding enteric adenoviruses. The predominant symptom of infections with enteric adenoviruses was diarrhea, with a mean duration of 8.6 days (Ad40) and 12.2 days (Ad41). One-third of the children with Ad41 infections had prolonged symptoms (greater than or equal to 14 days). The frequency of respiratory symptoms was low (21%). The established adenoviruses presented a different clinical picture, characterized by diarrhea of shorter duration, higher fever, and significantly increased occurrence of respiratory symptoms (79%). In conclusion, enteric adenoviruses appear to be an important cause of acute infantile gastroenteritis, second only to rotaviruses in this study.
Selective medium for isolation of Clostridium butyricum from human feces
Authors: Popoff M R
Published: January 2020

A selective medium, Clostridium butyricum isolation medium (BIM), is described for the isolation of C. butyricum from human feces. The BIM is a synthetic minimal medium and contains trimethoprim (16 micrograms/ml), D-cycloserine (10 micrograms/ml), and polymyxin B sulfate (20 micrograms/ml) as selective inhibitory agents. Qualitative tests indicated that C. butyricum and other butyric acid-producing clostridia grew on BIM, Clostridium sphenoides and Bacillus cereus produced small colonies, and other clostridia and other obligate anaerobic or facultatively anerobic bacteria were inhibited. Quantitative recovery of C. butyricum from cultures or seeded fecal samples was comparable with BIM and with complex medium, but the quantitative recovery of the other butyric acid-producing clostridia tested (C. beijerinckii, C. acetobutylicum) was lower with BIM than with complex medium. The BIM should aid the rapid isolation of C. butyricum from fecal samples and should be useful for bacteriological investigation of neonatal necrotizing enterocolitis.
Determination of catalase, peroxidase, and superoxide dismutase within the genus Legionella
Authors: Pine L , Hoffman P S , Malcolm G B , Benson R F , Keen M G
Published: January 2020

We examined 40 strains of Legionella for reduced-oxygen scavenging enzymes. Using a simple reaction chamber with a Swinney filter for the Beers and Sizer assay, we determined the catalase activity of live cells grown on buffered charcoal-yeast extract agar. For 29 strains of Legionella pneumophila, the apparent first-order rate constants for catalase ranged from 0.000 to 0.005. Similarly, low values ranging from 0.001 to 0.005 were observed for Legionella wadsworthii, Legionella oakridgensis, and Legionella gormanii. High catalase activities were found for Legionella jordanis, Legionella longbeachae, Legionella micdadei, and Legionella bozemanii, with first-order rate constant values of 0.010 to 0.035. Cell-free extracts were analyzed for catalase, peroxidase, and superoxide dismutase. Cell-free extracts of all strains had superoxide dismutase levels ranging from 8.2 to 30.5 U per mg of protein. The species could be characterized by their catalase and peroxidase since L. pneumophila and L. gormanii had only peroxidase (relative molecular weight [Mr], 150,000); L. dumoffii had a peroxidase (Mr, 150,000) plus a catalase (Mr, 174,000); and all remaining species had catalase only (Mr, 300,000, 220,000, or 150,000).
Successive extraction of specific protective immunoglobulins from pooled human sera
Authors: Yoshida K , Ichiman Y
Published: January 2020

By use of pooled human sera, specific protective immunoglobulins against the Smith-diffuse strain of Staphylococcus aureus, strains SS-620 and SS-619 of types III and II group B streptococci, and strain K-9 of Klebsiella pneumoniae were successively extracted from their whole cell and antibody complexes by elution with propionic acid containing 5% sucrose. Injection of 0.14, 0.05, 0.09, and 0.15 mg of these eluates in mice gave protection against lethal infection only with homologous strains. However, no protective effect was observed against these infections, even with considerably higher amounts of a conventional immunoglobulin preparation. The major components of the eluates were the three major immunoglobulins, immunoglobulin G (IgG), IgA, and IgM, although nonspecific proteins were also included. Protective activities of these eluates were absorbed out by their protection-inducing antigens, indicating that they contained specific protective immunoglobulins.
Detection of Chlamydia trachomatis in genital specimens by the Chlamydiazyme test
Authors: Jones M F , Smith T F , Houglum A J , Herrmann J E
Published: January 2020

Cotton swabs were used to collect two specimens each from 416 patients (206 males, 210 females) attending a sexually transmitted disease clinic. The first swab was transported in Specimen Storage Reagent and extracted in Specimen Dilution Buffer for enzyme immunoassay by Chlamydiazyme (Abbott Laboratories); the second swab was extracted into 2SP and inoculated into McCoy cell cultures. In the first phase of the study (215 patients: 111 males, 114 females) enzyme immunoassay results were positive (optical density greater than or equal to 0.1) in 30 of 35 instances in which Chlamydia trachomatis was isolated (sensitivity, 86%). Of 18 false-positive enzyme immunoassay results, 15 (83%) were cervical swabs (specificity, 90%). In a phase II study, using a modified Chlamydiazyme kit, 201 patients were tested (95 males, 106 females). Of 41 chlamydial isolates, 8 were not detected by the Chlamydiazyme test (sensitivity, 81%). Only three positive Chlamydiazyme test results could not be confirmed by culture (specificity, 98%). Overall, Chlamydiazyme assay provided a rapid (4 h), sensitive, and specific assay for the detection of chlamydial antigens.
Physicochemical inactivation of Lassa, Ebola, and Marburg viruses and effect on clinical laboratory analyses
Authors: Mitchell S W , McCormick J B
Published: January 2020

Clinical specimens from patients infected with Lassa, Ebola, or Marburg virus may present a serious biohazard to laboratory workers. We have examined the effects of heat, alteration of pH, and gamma radiation on these viruses in human blood and on the electrolytes, enzymes, and coagulation factors measured in laboratory tests that are important in the care of an infected patient. Heating serum at 60 degrees C for 1 h reduced high titers of these viruses to noninfectious levels without altering the serum levels of glucose, blood urea nitrogen, and electrolytes. Dilution of blood in 3% acetic acid, diluent for a leukocyte count, inactivated all of these viruses. All of the methods tested for viral inactivation markedly altered certain serum proteins, making these methods unsuitable for samples that are to be tested for certain enzyme levels and coagulation factors.
Characterization of uterine growth response to cholera toxin in hamsters and test of heat-labile enterotoxin from Escherichia coli
Authors: Alleva J J , Lamanna C
Published: January 2020

Cholera toxin (CT) and the heat-labile enterotoxin from Escherichia coli, when injected intraperitoneally into cycling hamsters but not rats or mice, induced a massive uterine growth similar to that normally induced by the implanting blastocyst during pregnancy. CT and heat-labile enterotoxin are the only known agents that have this action in any species. Uterine weight reached a maximal sixfold increase 48 h after injection of CT. Concurrent injection of estrogen, progesterone, and CT increased the maximal response to eightfold and eliminated differences in the response to CT injected on different days of the 4-day hamster estrous cycle. The dose response for CT, heat-labile enterotoxin, and CT plus estrogen plus progesterone was most linear (r greater than 0.93) when the logarithm of uterine weight was plotted against the dose of toxin. The hamster uterine weight response can serve as a simple, highly precise, and highly specific bioassay for CT and heat-labile enterotoxin.
Changes in antibody avidity after virus infections: detection by an immunosorbent assay in which a mild protein-denaturing agent is employed
Authors: Inouye S , Hasegawa A , Matsuno S , Katow S
Published: January 2020

In titrating serum immunoglobulin G antibody to viruses by enzyme-linked immunosorbent assay, we used two rows of wells for serial twofold dilutions of the serum; in one row, a low concentration of a protein denaturant, 0.5 or 1.0 M guanidine hydrochloride, was added to the diluent so that the binding of low-avidity antibodies to viral antigens on the solid phase was inhibited. We then compared the antibody titration curves obtained in the two rows. We found that the addition of the reagent resulted in a parallel leftward shift of the curves and that the extent of the shift was greater in early than in late sera from all of the three infections studied (Japanese encephalitis virus, rotavirus, and rubella virus infections). This procedure may be useful for estimation of the avidity of antibody in serum and, with further evaluation, may prove to be applicable to single-serum diagnosis of virus infections.
Evaluation of five commercially available immunodiffusion kits for detection of Coccidioides immitis and Histoplasma capsulatum antibodies
Authors: Johnson J E , Jeffery B , Huppert M
Published: January 2020

Five commercial test kits for the serodiagnosis of coccidioidomycosis and histoplasmosis based upon immunodiffusion were evaluated. The correlation of results with the test kits in the Clinical Laboratory varied from 71 to 100% for coccidioidomycosis. The correlation for coccidioidomycosis immunodiffusion testing varied from 57 to 83% when results from the test kits and the Mycology Research Laboratory were compared. Only 81% correlation was noted between the two laboratories when the same reference system was used. Results with the test kits for Histoplasma serodiagnosis and results from the Mycology Research Laboratory showed a correlation of 52 to 75%. There were no false-positive results with any system. All of the commercial kits were 100% specific for the diagnosis of both coccidioidomycosis and histoplasmosis, but the sensitivity of the immunodiffusion tests varied with the system used.
Studies of stools from pseudomembranous colitis, rotaviral, and other diarrheal syndromes by frequency-pulsed electron capture gas-liquid chromatography
Authors: Brooks J B , Nunez-Montiel O L , Basta M T , Hierholzer J C
Published: January 2020

Thirty-five patients with various diarrheal syndromes and 22 controls were studied. All stool samples were carefully cultured for Clostridium difficile, using selective isolation media. Cytotoxin assays with proper antitoxin neutralization were done in MRC-5 cells. The stool samples were extracted four times, three times at pH 2 and once at pH 10, using CHCl3 or ether. Derivatizations of extracts were done with trichloroethanol, heptafluorobutyric anhydride, and heptafluorobutyric anhydride-ethanol, and all derivatives were analyzed by frequency-pulsed electron capture gas-liquid chromatography (FPEC-GLC). A dedicated computer was used to assist in both qualitative and quantitative data analysis. Isocaproic acid (iC6) was always found in stool from which C. difficile was isolated and was absent in C. difficile-negative specimens. p-Cresol was found frequently in both persons with pseudomembranous colitis and controls. Tryptamine was found in stool containing C. bifermentans. The FPEC-GLC profiles of persons with acute diarrhea were very different from those of normal persons. Diarrhea associated with adenovirus and rotavirus, Klebsiella spp., and Escherichia spp. showed different FPEC-GLC patterns. Stools from well persons consistently contained full-scale peaks of pyruvic, acetic, propionic, isobutyric, butyric, isovaleric, and valeric acids. In rotavirus stools isobutyric, isovaleric, and valeric acids were reduced in quantity from those found in control stools, whereas propionic and butyric acids were increased.
Evaluation of cost-effectiveness and rationale for use of a selective culture plate for isolation of Staphylococcus aureus from stool specimens
Authors: Cashman J S , Smith C B , Weidner M , Matsen J M
Published: January 2020

An assessment was made of the necessity of performing routine screening for Staphylococcus aureus in stool specimens. A total of 527 stool specimens were evaluated. Because of the rare incidence of staphylococcal enterocolitis and the high ($2.50) screening cost, the results of this evaluation suggest that such a screening need not be performed routinely.
New biphasic culture system for isolation of mycobacteria from blood of patients with acquired immune deficiency syndrome
Authors: Berlin O G , Zakowski P , Bruckner D A , Johnson B L
Published: January 2020

A new biphasic medium consisting of a 7H11 agar slant and brain heart infusion broth liquid phase has been used for the past 10 months at the University of California at Los Angeles for isolation of Mycobacterium avium complex from blood. In 12 patients whose blood cultures were grown on this medium, the median time for isolation of M. avium complex was 7 days (range 6 to 15 days) compared with 21 to 27 days on a fungal medium and 28 to 38 days on routine blood culture medium. The system has provided a reliable and rapid way to obtain morphology and rapid identification of colonies produced from blood samples of patients with acquired immune deficiency syndrome, who are at high risk for M. avium complex mycobacteremia.
Recovery of Salmonella group B from blood and Salmonella group C2 from feces and serological evidence of dual infection in one patient
Authors: Papasian C J , Bartholomew W R , Neter E , Amsterdam D
Published: January 2020

A patient with a dual Salmonella infection is described. Salmonella group B was recovered from three blood culture sets but was not detected in seven stool cultures. Salmonella group C2 was isolated from three of seven stool cultures but was not recovered from blood cultures. Specific, non-cross-reactive antibodies to Salmonella groups B and C2 were detected in the sera of the patient by passive hemagglutination assays.
Diarrhea due to Plesiomonas shigelloides in cancer patients
Authors: Rolston K V , Hopfer R L
Published: January 2020

Plesiomonas shigelloides was isolated from the stools of two patients with gastrointestinal malignancies and from one "healthy" patient with diarrhea. No other enteric pathogens were isolated. One patient was neutropenic after antineoplastic chemotherapy. The two cancer patients had crampy abdominal pain and severe diarrhea and required antibiotic therapy for resolution of symptoms. The third patient responded to symptomatic treatment. Patients with gastrointestinal malignancies may be more susceptible to gastroenteritis caused by P. shigelloides than normal individuals, and these infections may be more severe than those seen in normal individuals.
Onset and duration of urinary antigen excretion in Legionnaires disease
Authors: Kohler R B , Winn W C , Wheat L J
Published: January 2020

The purposes of this study were to determine whether antigen is excreted by patients with Legionnaires disease early enough after the onset of symptoms to be useful for making therapeutic decisions and whether antigen excretion ends when successful treatment is concluded. Specific antigen was detected in the urine of 14 (88%) of 16 patients with Legionnaires disease during days 1 to 3 of symptoms, 33 (80%) of 41 patients during days 4 to 7, 25 (89%) of 28 patients during days 8 to 14, and 11 of 11 patients after day 14, by solid-phase immunoassays for serogroup 1 Legionella pneumophila antigen. Antigen excretion persisted for 42 days or longer after the onset of treatment in at least 15 patients. The longest documented duration of excretion was 326 days. We conclude that antigen can be detected approximately as often early after symptoms begin as later, allowing meaningful therapeutic decisions to be made, but that prolonged antigen excretion may negate the diagnostic value of urinary antigen detection for relapsing or recurrent L. pneumophila pneumonia.
Pseudomonas mesophilica and an unnamed taxon, clinical isolates of pink-pigmented oxidative bacteria
Authors: Gilardi G L , Faur Y C
Published: January 2020

Twenty-one strains of pink-pigmented bacteria, isolated from human clinical specimens and an environmental source, were compared with Pseudomonas mesophilica ATCC 29983 and Protaminobacter ruber ATCC 8457. These isolates were gram-negative, oxidative rods which were motile by means of a single polar flagellum; gave positive catalase, indophenol oxidase, urease, and amylase reactions; and grew slowly at 30 degrees C. Fourteen isolates conformed to the designated type strains Pseudomonas mesophilica ATCC 29983 and Protaminobacter ruber ATCC 8457. The remaining seven strains represented an undescribed taxon. These pink bacteria appear to be invaders of debilitated patients with an underlying chronic disease.
New, extended biotyping scheme for Campylobacter jejuni, Campylobacter coli, and "Campylobacter laridis"
Authors: Lior H
Published: January 2020

A biotyping scheme using improved media and methods for the detection of hippurate hydrolysis, rapid H2S production, and DNA hydrolysis was applied to 1,826 cultures of Campylobacter jejuni, Campylobacter coli and "Campylobacter laridis" isolates from human and nonhuman sources. Four biotypes were identified among C. jejuni: 57.3% of the isolates belonged to biotype I; 36.0%, to biotype II; 4.0%, to biotype III; and 2.7%, to biotype IV. C. coli organisms were differentiated into biotype I (67.0% of the isolates) and biotype II (33.0%). All "C. laridis" isolates belonged to biotype I. The combination of the biotyping scheme with the serotyping of campylobacters provided additional epidemiological markers by further differentiating the serogroups by species and biotypes.
Glucose-sucrose-potassium tellurite-bacitracin agar, an alternative to mitis salivarius-bacitracin agar for enumeration of Streptococcus mutans
Authors: Tanzer J M , Börjesson A C , Laskowski L , Kurasz A B , Testa M
Published: January 2020

An agar medium for selective recovery and enumeration of Streptococcus mutans was developed as an alternative to mitis salivarius-bacitracin (MSB) agar. Combinations of dyes, antibiotics, and tellurite were added to a nonselective medium which, because of its sucrose content, allowed easy recognition of S. mutans colonies. Candle jar incubation for 2 days, by comparison with anaerobic incubation, reduced background flora but did not diminish S. mutans recoveries from clinical samples. Quantitative comparisons were made of the simultaneous recoveries of a number of authentic S. mutans serotype representatives and fresh clinical isolates, using various glucose-sucrose-potassium tellurite-bacitracin (GSTB) formulations and mitis salivarius, MSB, and blood agars. Mitis salivarius counts were not detectably different from blood counts, but counts on MSB were distinctly lower. A formulation of the new medium containing 5% glucose 5% sucrose, 0.001% potassium tellurite, 0.3 U of bacitracin per ml (hence GSTB), and 2% agar gave recoveries nearly equal to those on mitis salivarius agar and much greater than those on MSB. The medium yielded readily recognized S. mutans colonies and facilitated detection of intracellular polysaccharide formers upon flooding with I2 reagent. Freshly isolated serotype c, E, and f colonies could often be distinguished from serotype d and g colonies, a distinction made reliable by testing for intracellular polysaccharide. A study of 300 salivary samples revealed GSTB to give significantly higher recoveries than MSB. About 72% of all samples were substantially underestimated for S. mutans with MSB, and 6.7% of samples were falsely negative for S. mutans with MSB. Recovery of background flora on GSTB was as low or lower than on MSB, and both types of agar could be stored for at least 9 weeks without notable change of selectivity. Thus, GSTB agar appears to be simple and reliable to use and requires no anaerobic incubation. Caution is voiced about interpretation of data previously reported which evaluated S. mutans on MSB agar.
Enzymatic profiles of Enterobacter sakazakii and related species with special reference to the alpha-glucosidase reaction and reproducibility of the test system
Authors: Muytjens H L , van der Ros-van de Repe J , van Druten H A
Published: January 2020

The enzymatic profiles of Enterobacter sakazakii, Enterobacter cloacae, Enterobacter aerogenes, and Enterobacter agglomerans were determined with the API ZYM system (API System S.A., La Balme Les Grottes, France). Each assay was performed three times. A simple formula was derived and applied to assess the reproducibility of the API ZYM tests. In addition, a separate alpha-glucosidase test was performed. All E. sakazakii isolates produced alpha-glucosidase, in contrast to the other Enterobacter isolates. No phosphoamidase activity was detected in any of the E. sakazakii isolates, whereas it was present in 72% of E. cloacae, 89% of E. agglomerans, and 100% of E. aerogenes isolates. It was concluded that detection of alpha-glucosidase permits rapid and reliable differentiation between E. sakazakii and other Enterobacter species. The reproducibilities of alpha-glucosidase and phosphoamidase reactions were estimated to be 89 and 81%, respectively.
Enzyme immunoassay for the detection of group A streptococcal antigen
Authors: Knigge K M , Babb J L , Firca J R , Ancell K , Bloomster T G , Marchlewicz B A
Published: January 2020

A competitive inhibition enzyme immunoassay for the detection of Streptococcus pyogenes directly from throat specimens or from solid bacteriological medium is described. Group A-specific polysaccharide adsorbed onto treated polystyrene beads, in conjunction with rabbit antibody to S. pyogenes, was used to determine the presence of the polysaccharide antigen. Inhibition values in excess of 65% were observed with 10(4) or more CFU of S. pyogenes per test. An inhibition of 25% was demonstrated with as few as 10(3) CFU per test. Heterologous microorganisms tested at 10(6) CFU per test reacted at levels of inhibition less than 25%. Two types of bacterial transport medium and swabs of different fiber compositions did not alter the assay performance. Accurate identification of S. pyogenes was achieved by testing single colonies picked directly from blood agar plates which had been incubated for 18 to 24 h. In addition, the assay was performed on throat specimens from children and adults having pharyngitis. A single-swab, blind study was conducted in which enzyme immunoassay reactivity was compared with results of blood agar culture and bacitracin sensitivity. When there were discordant results, serological identification was used as the confirmatory test. At an optimal cutoff value of 40% inhibition, sensitivity and specificity by enzyme immunoassay were 97.0% and 97.9%, respectively, as compared with confirmed culture results. The assay has an incubation time of 3 h and is a sensitive and specific method for the detection of S. pyogenes antigen.
Comparison of the Lumac and Monolight systems for detection of bacteriuria by bioluminescence
Authors: Drow D L , Baum C H , Hirschfield G
Published: January 2020

The development of practical and rapid methods for detection of infectious-disease-producing agents in clinical specimens is the most important current goal of clinical microbiology. Bioluminescence is a technique which is rapid and potentially sensitive enough to detect significant numbers of bacteria in urine specimens. To determine whether bioluminescence is practical and cost effective for routine use, we compared two commercially available instruments and kits, Lumac and Monolight, to standard bacterial cultures on 986 urine specimens. Lumac had an overall 83.7% agreement with cultures, a sensitivity of 92.4%, and a specificity of 79.4%. Monolight had 83.5% agreement with cultures, a sensitivity of 89.1%, and a specificity of 81.8%. There were 13.8% false-positive results and 2.5% false-negative results with both systems. When only potentially significant organisms were included, the false-negative rate was reduced to ca. 1%. Both systems are sufficiently accurate to be recommended for routine use. The cost of bioluminescence is higher than that of bacterial cultures, and bioluminescence may not be cost effective in some laboratories.