bluuebunny/crossref_metadata_2025 huggingface dataset:
Production of toxic shock syndrome toxin 1 by Staphylococcus aureus as determined by tampon disk-membrane-agar method
Authors: Robbins R N , Reiser R F , Hehl G L , Bergdoll M S
Published: January 2020

The influence of 17 commercially available tampons on production of toxic shock syndrome toxin 1 (TSST-1) by Staphylococcus aureus was investigated by using a tampon disk method. Filter membranes overlaying agar medium (with or without blood) in small petri dishes were spread inoculated with a TSST-1-producing strain of S. aureus. Disks cut from unrolled tampons were pressed and laid on the inoculated membranes; incubation was for 19 h at 37 degrees C with 5% CO2 in air. CFU on the membranes and in the disks were enumerated, and the presence of TSST-1 in the disks and in the agar layers was determined. Tampons made of different materials supported characteristic levels of cell growth and toxin production in the tampon. Colonization of the interface surface of the tampon disks was heavy. The number of CFU extracted from the tampon disks ranged from 5 X 10(10) to 82 X 10(10). There was little variation in the CFU recovered from the membranes ([1.9 +/- 0.4] X 10(11)). Sixty to 170 micrograms of TSST-1 was recoverable from the agar, with an additional 10 to 90 micrograms recoverable from tampon disks, depending on the type of tampon disk. The amount of toxin in the agar layer from the various tampon disks was relatively constant and indicated an important contribution of toxin from vaginal S. aureus cells not growing in the tampon. The main role of tampons in toxic shock syndrome may be that of providing a fibrous surface for heavy colonization and sufficient air for TSST-1 production.
Comparison of sensitivity of BHK-21 and murine neuroblastoma cells in the isolation of a street strain rabies virus
Authors: Rudd R J , Trimarchi C V
Published: January 2020

The sensitivities of BHK-21 (C-13) and murine neuroblastoma (C-1300; clone NA) cells for the isolation of small quantities of a street strain rabies virus were compared. Suspensions of brain from mice sacrificed prior to the onset of clinical signs of rabies were used to stimulate weakly positive diagnostic specimens. The results of cell culture isolation were compared with those of the direct fluorescent-antibody test and virus isolation in weanling mice. Neuroblastoma cells were more sensitive to the street strain rabies virus than were BHK-21 cells. Neuroblastoma cell virus isolation, the mouse inoculation test, and the fluorescent-antibody test all showed comparable sensitivity.
Pseudoepidemic of aspergillosis after development of pulmonary infiltrates in a group of bone marrow transplant patients
Authors: Weems J J , Andremont A , Davis B J , Tancrede C H , Guiguet M , Padhye A A , Squinazi F , Martone W J
Published: January 2020

During February and March 1985, seven patients in the pediatric bone marrow transplant unit (PBMTU) of a 350-bed cancer hospital developed pulmonary infiltrates. Five of the patients had Aspergillus spp. isolated from the respiratory tract, and two of these patients had histologic evidence of aspergillosis. Between 26 February and 22 April, Aspergillus spp. were isolated in a total of 70 cultures from 39 hospitalized patients. Of the 70 cultures, 14 (group 1) were from respiratory specimens of PBMTU patients with pulmonary infiltrates and were submitted to the laboratory intermittently over the 56-day period. However, of the other 56 Aspergillus-positive cultures (group 2), 41 (73%) were submitted on six days during this period (P less than 0.001, chi-square goodness of fit), including 8 blood cultures submitted on one day. When Aspergillus sp. was recovered from group 1 cultures early during this period, the isolates were stored in the culture-processing room. Aspergillus isolates were not handled in a biological safety cabinet, and blood cultures were done by using a system which requires opening of an evacuated bottle to room air. The presence of stored Aspergillus isolates was associated with a markedly elevated concentration of airborne fungi in the culture-processing room. After removal of the stored Aspergillus isolates from the culture-processing room, the concentration of airborne fungi returned to background level and there were no further Aspergillus-positive cultures. These findings suggested that group 2 cultures had been contaminated by stored Aspergillus isolates. No evidence for a common source of infection was found in the PBMTU patients with pulmonary infiltrates.
Potential use of continuous cell lines to distinguish between pathogenic and nonpathogenic Listeria spp
Authors: Farber J M , Speirs J I
Published: January 2020

Continuous cell lines were tested for their potential use in distinguishing pathogenic from nonpathogenic Listeria species. Listeria monocytogenes and Listeria ivanovii strains were lethal for mice, and culture filtrates were cytotoxic for cultured cells and hemolytic for sheep erythrocytes, while Listeria innocua, Listeria grayi, and Listeria murrayi strains were negative in all three tests. The eight cell lines tested were all affected but varied in sensitivity, with the Chinese hamster ovary cell line being the most sensitive. Cytolytic effect was noted within minutes of the addition of undiluted filtrates, with optimum titers obtained by 24 h.
HeLa cell-adherent enteropathogenic Escherichia coli in children under 1 year of age in Thailand
Authors: Echeverria P , Taylor D N , Bettelheim K A , Chatkaeomorakot A , Changchawalit S , Thongcharoen A , Leksomboon U
Published: January 2020

Enteropathogenic Escherichia coli (EPEC) was isolated from 11% of 148 Hmong children under 1 year old with diarrhea at a refugee camp in northern Thailand. Of 16 children with EPEC-associated diarrhea, 11 were infected with EPEC that adhered to HeLa cells in a diffuse pattern, 3 were infected with EPEC that adhered to HeLa cells in a localized adherence (LA) pattern, and 2 were infected with EPEC that were nonadherent. In Bangkok, EPEC was isolated from 6% of 64 children under 1 year old with diarrhea and 7% of 56 children of the same age without diarrhea. Of four children with diarrhea, two were infected with EPEC with an LA pattern, and two were infected with nonadherent EPEC. Of four children without diarrhea, one was infected with EPEC with an LA pattern, one was infected with EPEC that adhered in a diffuse pattern, and two were infected with nonadherent EPEC. The 21 EPEC isolates with an LA pattern hybridized with the EPEC adherence factor DNA probe. EPEC was the only enteric pathogen identified in 16 (80%) of 20 children with EPEC-associated diarrhea. EPEC was as frequently isolated from children under 1 year old as were other bacterial enteric pathogens. The problem of identifying EPEC with pools of polyvalent antisera are described, and the need to identify additional enteropathogenic determinants of EPEC is discussed.
Separation of Haemophilus influenzae type b subtypes by numerical analysis
Authors: Elliott J A , Bosley G S , Carlone G M , Plikaytis B D , Facklam R R
Published: January 2020

Outer membrane proteins (OMPs) were prepared from 20 previously established subtypes of Haemophilus influenzae type b. Proteins were separated by one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis (11% acrylamide). Each lane in the gels contained two internal molecular weight standards. One central lane contained a range of molecular weight standards, which were used to calculate a molecular weight curve for each gel. Migration distances of the OMPs were determined with a soft laser-scanning densitometer, and the distances were normalized by using the mean migration distances of the internal standards. The protein patterns of all subtypes were compared by a recently described method (B.D. Plikaytis, G.M. Carlone, and B.B. Plikaytis, J. Gen. Microbiol. 132:2653-2660, 1986). All subtypes could be differentiated by this method. The ability to store and compare numerous OMP patterns from different isolates of H. influenzae type b, separated with a single homogeneous polyacrylamide gel, will facilitate the continued development of a subtyping system based on these proteins.
New infectious spirochete isolated from short-tailed shrews and white-footed mice
Authors: Anderson J F , Johnson R C , Magnarelli L A , Hyde F W , Andreadis T G
Published: January 2020

A spirochete with two periplasmic flagella was isolated from the blood or tissues of spleens and kidneys from short-tailed shrews (Blarina brevicauda) and white-footed mice (Peromyscus leucopus) in Connecticut and Minnesota. After inoculation, the shrew-mouse spirochete infected Swiss mice and Syrian hamsters. This spirochete is morphologically and serologically distinct from the species of Treponema, Borrelia, Leptospira, and Spirochaeta examined.
Antibody to a synthetic oligopeptide in subjects at risk for human immunodeficiency virus infection
Authors: Smith R S , Naso R B , Rosen J , Whalley A , Hom Y L , Hoey K , Kennedy C J , McCutchan J A , Spector S A , Richman D D
Published: January 2020

Detection of antibodies to human immunodeficiency virus (HIV) by enzyme-linked immunosorbent assay (ELISA) is the accepted method to screen blood products at risk to transmit infection. The presence of antibodies to HIV in 565 serum specimens from 274 patients with acquired immunodeficiency syndrome (AIDS) or AIDS-related complex, symptomatic and asymptomatic subjects at risk for AIDS, and controls was determined with an ELISA that incorporates synthetic peptides (designated E32/E34) representing sequences in the envelope glycoprotein gp41. Of 105 specimens from patients with AIDS or AIDS-related complex, 3 specimens that were negative by commercially licensed ELISA and immunoblot test were similarly unreactive in the E32/E34 ELISA. For homosexual men with generalized lymphadenopathy, 186 specimens were positive by the E32/E34 ELISA and 63 specimens were negative. In comparison, with the licensed ELISA, 184 of these samples were positive and 65 samples were negative. The two samples that were positive in the E32/E34 ELISA but not the commercial kit were also positive by immunoblotting. Sequential sera from one individual who apparently underwent seroconversion according to the commercial assays were all positive by E32/E34 ELISA and immunoblotting. Thus, the ELISA with synthetic peptides is an extremely sensitive and specific test of antibody response to HIV and has not yet yielded a negative result with a Western blot (immunoblot)-confirmed antibody-positive serum.
Characteristics and sites of infection of Eubacterium nodatum, Eubacterium timidum, Eubacterium brachy, and other asaccharolytic eubacteria
Authors: Hill G B , Ayers O M , Kohan A P
Published: January 2020

Three new species, Eubacterium nodatum, Eubacterium timidum, and Eubacterium brachy, were described, primarily from subgingival samples taken from patients with moderate and severe adult periodontitis. Except for the isolation of E. brachy from a pleuropulmonary infection, these species have not been reported from other infected body sites. We report on the isolation of these species and an undescribed group (D-6) of asaccharolytic eubacteria also found in periodontal disease from numerous different sites of infection, mostly the head and neck. A similarity in cellular morphological properties of E. nodatum and Actinomyces sp. was noted previously. Additional similarities, particularly to Actinomyces israelii, that we found are the formation of molar tooth colonies and the isolation from cases of lumpy jaw and from the genital tract of women in association with the use of an intrauterine contraceptive device. E. timidum and E. brachy did not occur more often from any particular site outside of the head, neck, and respiratory tract. The group D-6 strains came from a variety of sites in the trunk and pelvis. These species are all obligately anaerobic, asaccharolytic, and generally nonreactive, and they grow poorly and slowly on media commonly used to isolate anaerobic bacteria. L-Lysine (0.5%) markedly stimulated the growth of E. nodatum and, to a lesser extent, another acetate- and butyrate-producing group, Eubacterium sp. group D-6, but we did not find comparable stimulants for the other species. We found the production of phenyl acetate to be a helpful marker in the identification of E. timidum and Eubacterium sp. group D-6. Although the isolation and identification of most of these species remain somewhat difficult, the evidence from dental infections and the present report suggests that these species are potential pathogens that are likely to be overlooked in infected clinical material without special attention to more prolonged incubation and use of enriched isolation media.
Rapid identification using a specific DNA probe of Mycobacterium avium complex from patients with acquired immunodeficiency syndrome
Authors: Kiehn T E , Edwards F F
Published: January 2020

Specific DNA probes (Gen-Probe Corp., San Diego, Calif.) for Mycobacterium avium, Mycobacterium intracellulare, and Mycobacterium tuberculosis were compared with conventional methods for the identification of isolates of the Mycobacterium avium complex. A total of 56 isolates of M. avium complex were recovered from 34 respiratory, 13 blood, 6 stool, and 3 urine samples from 23 patients. A total of 33 isolates were tested directly from Middlebrook 7H11 agar plates, and 23 isolates were tested directly from BACTEC radiometric 12B bottles (Johnston Laboratories, Inc., Towson, Md.). Of the 56 M. avium complex isolates, 41 tested positive with the M. avium probe, 4 were positive with the M. intracellulare probe, and 7 were positive with both probes. Four direct tests from BACTEC bottles were initially negative but were subsequently M. avium probe positive when subcultures from Lowenstein-Jensen agar were tested. All 56 strains were negative when tested with the M. tuberculosis probe.
Hydrolysis of indoxyl acetate by Campylobacter species
Authors: Mills C K , Gherna R L
Published: January 2020

One hundred and twelve Campylobacter strains comprising 15 species and subspecies were examined for their ability to hydrolyze indoxyl acetate. All strains of C. coli, C. cryaerophila, C. fennelliae, and C. jejuni hydrolyzed the compound, whereas three strains of C. cinaedi were negative and a fourth was weakly positive. Representatives of all other species were negative. Organisms that hydrolyzed indoxyl acetate did so regardless of the medium used.
Ocular infection in a newborn caused by Neisseria mucosa
Authors: Gini G A
Published: January 2020

Neisseria mucosa was isolated in pure culture from a purulent ocular infection of a newborn. The initial Gram-stained smear revealed intracellular gram-negative diplococci. The organism showed resistance to vancomycin, colistin, and trimethoprim in susceptibility testing and grew well on Thayer-Martin medium.
Bilateral abscessed orchiepididymitis associated with sepsis caused by Veillonella parvula and Clostridium perfringens: case report and review of the literature
Authors: Arrosagaray P M , Salas C , Morales M , Correas M , Barros J M , Cordon M L
Published: January 2020

Veillonella species is a gram-negative coccus which is part of the anaerobic normal flora in the oral cavity, small intestine, upper respiratory tract, vagina, and urinary tract. The role that this organism plays in infection is not well known, and it is generally associated with other bacteria. We present a case of bilateral abscessed orchiepididymitis associated with septicemia due to Veillonella parvula and, later, to Clostridium perfringens, with the development of severe renal insufficiency and septic shock, which resolved favorably with antibiotic therapy, treatment of shock, and hyperbaric oxygen therapy. In reviewing the literature, we have not found any other case of sepsis due to Veillonella sp. associated with urological disorders.
Comparative analysis of two rapid automated methods and a semiautomated version of the urease method for determining aminoglycoside concentrations in serum
Authors: Wells P , Robbins E , Cowley R , Noone P
Published: January 2020

The Syva EMIT Autolab 6000 and the Abbott TDX automated methods for measuring serum aminoglycoside concentrations were compared with each other and with a new semiautomated version of the urease technique. Each was evaluated for accuracy, reproducibility, cost, and ease of use. All three methods gave satisfactory results, although the Abbott TDX was the most accurate. Both automated methods gave results within minutes, whereas the new urease method, which involved more initial manipulation, took 1.25 h to complete (mainly incubation time). There was no difference in accuracy of performance between experienced and inexperienced operators. The new urease method was much cheaper in terms of initial capital expenditure and in cost per test and needed no provision of manufacturer's back-up maintenance services. This could prove invaluable in situations where financial resources are at a premium. Otherwise, the Abbott TDX is currently our method of choice, and reasons for its preference to the EMIT system are listed.
Diagnosis of porcine and bovine enteric coronavirus infections using cloned cDNA probes
Authors: Shockley L J , Kapke P A , Lapps W , Brian D A , Potgieter L N , Woods R
Published: January 2020

Molecular clones representing the first 2,000 bases from the 3' end of the porcine transmissible gastroenteritis coronavirus genome and the first 2,160 bases from the 3' end of the bovine enteric coronavirus genome were used in dot blot hybridization assays to detect viral RNA from cell culture and from fecal specimens. In each case, the cloned DNA represents approximately 10% of the genome. The cloned sequence for each virus encompasses the 3' noncoding region, the nucleocapsid protein gene, and a large portion of the matrix protein gene. 32P-labeled cDNA probes prepared from these clones detected as little as 25 pg of RNA from the parental virus but did not detect RNA from the nonparental virus even when amounts of up to 10 ng per dot were used. This specificity reflects the antigenic diversity between these two coronaviruses. The hybridization assay could also detect coronaviruses antigenically closely related to the parental virus but not coronaviruses belonging to an antigenically unrelated subgroup. Dot blot hybridization for transmissible gastroenteritis coronavirus diagnosis was compared with the routine procedures of virus isolation and electron microscopy as a diagnostic test.
Comparative study of tissue culture and mouse inoculation methods for demonstration of Toxoplasma gondii
Authors: Derouin F , Mazeron M C , Garin Y J
Published: January 2020

Two methods for the isolation of Toxoplasma gondii were analyzed and compared. Bradyzoites or tachyzoites of three strains of T. gondii were injected into mice and introduced in parallel onto MRC5 fibroblasts cultured on cover slips. In the cultures, the parasites were more readily identified by an indirect immunofluorescence assay than by examination of unstained or Giemsa-stained cultures. With the RH strain, the tachyzoites replicated actively, and large foci of parasites were observed in 24 h. The bradyzoites or tachyzoites of the other strains could also be cultivated, but grew rather slowly; 2 days after inoculation, early stages of multiplication could be observed: from day +4, Toxoplasma clusters or foci were easily identified at a x100 magnification. The course of infection in mice was greatly dependent on the virulence of the strain and on the parasitic stage inoculated. In the chronically infected mice, evidence of Toxoplasma infection was only detected 45 days after inoculation through the demonstration of cysts in the brain or the presence of specific antibodies in the serum. The mean ratio of infected mice and positive cultures was compared in relation to the inoculum size. The tissue culture method was found to be at least as sensitive as mouse inoculation. Since Toxoplasma organisms may be isolated within a few days in tissue culture, it is proposed that this method should be used when early isolation of the parasite is crucial for the diagnosis of toxoplasmosis.
Comparison of modified Minitek system with Staph-Ident system for species identification of coagulase-negative staphylococci
Authors: Crouch S F , Pearson T A , Parham D M
Published: January 2020

A modified Minitek system (BBL Microbiology Systems, Cockeysville, Md.) for species identification of coagulase-negative staphylococci was compared with the Staph-Ident system (Analytab Products, Plainview, N.Y.). The conventional method of Kloos and Schleifer (J. Clin. Microbiol. 1:82-88, 1975) was used as the reference method for identification. When tested with 78 coagulase-negative staphylococcal isolates from 63 children with cancer. Minitek concurred with the conventional identification in 67 (86%) isolates and Staph-Ident concurred in 61 (78%) isolates. Identification of species other than Staphylococcus epidermidis was better with Staph-Ident (19 of 23 isolates) than with Minitek (14 of 23 isolates). Concordance of results was likewise high, 88% (7 of 8) for Minitek and 100% (8 of 8) for Staph-Ident in studies with eight coagulase-negative staphylococcal strains obtained from the American Type Culture Collection (Rockville, Md.). We conclude that the modified Minitek system is a practical and reliable test for identifying coagulase-negative staphylococci in clinical microbiology laboratories. Its versatility and larger repertoire of biochemical tests may offer advantages over the Staph-Ident system.
Immunoglobulin class and immunoglobulin G subclass enzyme-linked immunosorbent assays compared with microneutralization assay for serodiagnosis of mumps infection and determination of immunity
Authors: Linde G A , Granström M , Orvell C
Published: January 2020

Total immunoglobulin G (IgG) and IgG subclass reactivities with purified mumps glycoproteins (GP) and nucleoprotein (NP), measured in enzyme-linked immunosorbent assays (ELISAs), were compared with titers in a mumps microneutralization assay (NT). For determination of mumps immunity, the sensitivity of both ELISAs was 100% in comparison with the NT and the specificity was 90%. IgG1 was the dominant subclass against the two antigens found in seropositive healthy individuals. In samples from patients with clinical mumps infections and positive mumps IgM, titer rises of total IgG against NP were invariably seen before GP titer rises. Significant but often late titers rises in NT were found in all patients. Changes of IgG1 levels against both antigens followed the changes of total specific IgG. High levels of IgG3 against NP were diagnostic for mumps infection. In parainfluenza infections, titer rises in the mumps ELISAs and NT were found, but mumps IgM, NP IgG3, and the high ratio between the NP and GP titers found in early samples from patients with mumps infection were not observed.
Naturally occurring auxotrophs of Campylobacter jejuni and Campylobacter coli
Authors: Tenover F C , Patton C M
Published: January 2020

The nutritional requirements for 439 Campylobacter jejuni isolates and 46 Campylobacter coli isolates were determined by using a previously described chemically defined medium, campylobacter defined medium. With this medium, 45% of both human and nonhuman C. jejuni isolates demonstrated auxotrophic requirements. None of the 46 C. coli isolates studied demonstrated requirements for amino acids on campylobacter defined medium. The most common auxotrophic requirement among C. jejuni isolates was for methionine, which was present as a single requirement or in combination with other markers in 21% of human and 28% of nonhuman isolates. There was no correlation between plasmid carriage and auxotype, and a comparison of the Lior serotypes of 472 of the strains showed a correlation only between proline auxotrophs and Lior serotype 11 for strains isolated in the Seattle-King County region.
Ampicillin disk diffusion susceptibility testing of Haemophilus influenzae
Authors: Doern G V , Daum G S , Tubert T A
Published: January 2020

A total of 114 strains of Haemophilus influenza were characterized with respect to beta-lactamase production and ampicillin MIC. Of this total, 41 strains produced a TEM-type beta-lactamase, and ampicillin MICs for these strains were greater than or equal to 2.0 microgram/ml. It was found that 54 strains lacked TEM-type beta-lactamase activity, and ampicillin MICs for them were less than or equal to 0.5 microgram/ml. The remaining 19 strains were beta-lactamase negative, but ampicillin MICs were greater than or equal to 2.0 micrograms/ml. Disk diffusion susceptibility tests were performed with two media, i.e., Mueller-Hinton agar containing 1.0% hemoglobin and 1.0% IsoVitaleX supplement (CHOC-MHA) and enriched chocolate agar (CHOC), by using disks containing 10 and 2 micrograms of ampicillin. If strains of H. influenzae for which ampicillin MICs were greater than or equal to 2.0 micrograms/ml were considered resistant, while strains for which MICs were less than or equal to 0.5 microgram/ml were considered susceptible, the following zone diameter interpretive criteria were identified as indicating ampicillin susceptibility: CHOC-MHA (10-micrograms disks), greater than or equal to 20 mm; CHOC-MHA (2-micrograms disks), greater than or equal to 17 mm; CHOC (10-micrograms disks), greater than or equal to 25 mm; and CHOC (2-micrograms disks), greater than or equal to 20 mm. In all cases, zones of inhibition less than those listed above would be interpreted as indicating resistance. Each of these four combinations was found to be essentially equivalent in identifying susceptible and resistant strains of H. influenzae, irrespective of beta-lactamase production.
Comparison of competitive and indirect enzyme-linked immunosorbent assays for detection of bluetongue virus antibodies in serum and whole blood
Authors: Afshar A , Thomas F C , Wright P F , Shapiro J L , Shettigara P T , Anderson J
Published: January 2020

An indirect (I) enzyme-linked immunosorbent assay (ELISA) and a competitive (C) ELISA, using a group-specific monoclonal antibody against bluetongue virus (BTV), are described for the detection of antibodies to BTV in cattle and sheep sera. The performance of these assays in detecting anti-BTV antibody in sequential serum samples and eluates from whole blood (WB) dried on filter paper from three calves and four sheep experimentally infected with type 10 BTV was evaluated. The C-ELISA was superior to the I-ELISA in the detection of anti-BTV antibody in the sera and WB samples from both cattle and sheep early after infection with BTV. BTV antibodies were demonstrable by C-ELISA in all the bovine and ovine sera and WB eluates by 9 days postinfection; whereas the I-ELISA results for sheep sera and WB eluates were similar, anti-BTV antibody was not detected in bovine serum and WB eluates until 26 and 14 days postinfection, respectively. While both ELISAs proved reliable, under the present test conditions involving detection of early postinfection reactions of experimentally infected animals, the C-ELISA was always as sensitive or more sensitive than the standard agar gel immunodiffusion test, the modified complement fixation test, and the plaque neutralization tests in the detection of anti-BTV antibodies. Unlike observations with the immunodiffusion test, no reaction was seen between BTV antigen and bovine epizootic hemorrhagic disease virus antiserum in either ELISA. The results suggest that either ELISA may be suitable for routine diagnostic testing and may have the potential to replace other tests for detection of anti-BTV group-specific antibodies and that the C-ELISA may have the most potential.
Enzyme-linked immunosorbent assay for detection of antibodies to the venereal disease research laboratory (VDRL) antigen in syphilis
Authors: Pedersen N S , Orum O , Mouritsen S
Published: January 2020

An enzyme-linked immunosorbent assay (ELISA) for detection of immunoglobulin G (IgG) and IgM to cardiolipin, lecithin, and cholesterol (VDRL [Venereal Disease Research Laboratory] ELISA) is described. The specificity of the VDRL ELISA for IgG and IgM was 99.6 and 99.5%, respectively, with sera from 1,008 persons without syphilis. For a group of patients with false-positive results in traditional nontreponemal tests and for patients with autoimmune diseases, the VDRL ELISA for IgG had a higher specificity than the VDRL ELISA for IgM. The sensitivity for IgG and IgM with 118 sera from patients with untreated syphilis was 96.6 and 94.9%, respectively, which was equivalent to the sensitivities of the traditional nontreponemal tests. The performance of the VDRL ELISA was compared with that of an ELISA that uses cardiolipin as the antigen (cardiolipin ELISA). The VDRL ELISA was significantly more sensitive (P less than or equal to 0.01) than the cardiolipin ELISA with 25 sera from syphilis patients but was less sensitive (P less than or equal to 0.01) with 53 sera from patients with autoimmune diseases. The antibody reactivity in the VDRL ELISA could not be absorbed out by lecithin and cholesterol, and the sera from patients with syphilis did not react in an ELISA that uses cholesterol and lecithin as the antigen. This indicates that cholesterol and lecithin, although not antigenic by themselves, may change the structural form of the epitope on cardiolipin so that it becomes more recognizable for antibodies in syphilis and less recognizable for antibodies in autoimmune diseases. The results of the VDRL ELISA were expressed in percentages of the absorbance value of a positive control. The VDRL ELISA gave, without titration of sera, quantitative results that correlated with the quantitative results of the traditional nontreponemal tests obtained by titration. The VDRL ELISA will be well suited for large-scale testing for syphilis and may replace other nontreponemal tests.
Comparison of a new, rapid enzyme immunoassay with a latex agglutination test for qualitative detection of rubella antibodies
Authors: Ferraro M J , Kallas W M , Welch K P , Lau A Y
Published: January 2020

A total of 450 sera were tested for rubella virus antibodies by using a new, rapid enzyme immunoassay, SUDS Rubella. The results were compared with those obtained by using the Rubascan test, a well-established latex agglutination method. The sensitivity of the SUDS Rubella was 99.5%, and the specificity was 100%, when compared with Rubascan. The SUDS Rubella test can be performed in 10 min and provides an accurate screening test for the detection of rubella antibodies.
Prevalence and characterization of hippurate-negative Campylobacter jejuni in King County, Washington
Authors: Totten P A , Patton C M , Tenover F C , Barrett T J , Stamm W E , Steigerwalt A G , Lin J Y , Holmes K K , Brenner D J
Published: January 2020

A total of 593 strains of thermophilic Campylobacter species were isolated either from humans with diarrhea or from poultry in King County, Washington. Of these strains, 98 (52 hippurate-positive strains and all 46 of the hippurate-negative strains) were selected for further phenotypic characterization and genetic classification. Hippurate hydrolysis, the test typically used to differentiate Campylobacter jejuni and C. coli, did not always correlate with the genetic classification. All hippurate-positive strains were classified as C. jejuni. Of the hippurate-negative strains, 20% were C. jejuni, 78% were C. coli, and 2% were C. laridis. Assuming that the remaining hippurate-positive strains were all C. jejuni, then hippurate-negative C. jejuni represented a small percentage (9 of 556 or 1.6%) of C. jejuni strains but a significant percentage (9 of 46 or 20%) of hippurate-negative strains. This finding suggests that hippurate hydrolysis should not be used as the sole criterion for differentiating thermophilic Campylobacter species, particularly when describing the disease states associated with these organisms.
Rotavirus isolate WI61 representing a presumptive new human serotype
Authors: Clark H F , Hoshino Y , Bell L M , Groff J , Hess G , Bachman P , Offit P A
Published: January 2020

A virus (strain WI61) representing a presumptive new human serotype was isolated from an 18-month-old child with gastroenteritis admitted to Children's Hospital of Philadelphia in February 1983. The WI61 virus was clearly distinguished by cross-neutralization tests from human rotaviruses of serotypes 1, 2, 3, and 4, human 69M, and representative bovine (NCDV), porcine (OSU), and chicken (Ch2) rotaviruses. Antisera generated in guinea pigs hyperimmunized to WI61 virus displayed a partial cross-reactivity with rotaviruses of human serotypes 1, 2, 3, and 4. By means of studies with reassortant rotaviruses, it was presumptively determined that the WI61 virus cross-reactive antigenic determinants are localized on the vp3 surface polypeptide coded by gene segment 4. The characteristic RNA genome electropherotype of WI61 virus was observed in 5 of 59 cases of infant gastroenteritis detected in 1983 and 1984 but has not been observed in a subsequently at Children's Hospital. Serotype WI61-specific neutralizing antibodies were observed in a majority of sera of normal adults and infants of less than 4 or greater than 12 months of age collected in the Philadelphia area. Median antibody titers to WI61 equaled or exceeded those to rotaviruses of serotype 1 or 3. Each of seven samples of commercial cow's milk exhibited neutralizing antibodies to WI61 virus at a titer greater than or equal to that to serotype 1 or 3 or bovine (strain NCDV) rotavirus. However, WI61 rotavirus did not induce disease or a specific serum-neutralizing antibody response when fed to a caesarean-derived colostrum-deprived newborn calf. WI61 rotavirus caused diarrhea in newborn mice with a 50% diarrhea-inducing dose of 10(7.0) PFU.
Test-of-cure analysis by direct immunofluorescence for Chlamydia trachomatis after antimicrobial therapy
Authors: Nachamkin I , Sawyer K , Skalina D , Crooks G W , Ciotti R , Sondheimer S J
Published: January 2020

The direct immunofluorescence assay (DFA) was compared with culture for test-of-cure analysis for Chlamydia trachomatis in patients 7 to 10 days after antimicrobial therapy was given. DFA test-of-cure results correlated with culture results in 79.5% of 39 patients. Of DFA-negative patients, 97% had negative cultures. Six of seven patients with borderline DFA results had negative culture results.
Rapid and improved gas-liquid chromatography technique for detection of hippurate hydrolysis by Campylobacter jejuni and Campylobacter coli
Authors: Bär W , Fricke G
Published: January 2020

A gas-liquid chromatographic method which requires no chloroform extraction of the split products has been investigated for the detection of hippurate hydrolysis by Campylobacter spp. This technique gave better reproducibility than other tests also used in this study and allows the routine use of the gas-liquid chromatographic method for identification of Campylobacter isolates.
Association between specific plasmids and relapse in typhoid fever
Authors: Gotuzzo E , Morris J G , Benavente L , Wood P K , Levine O , Black R E , Levine M M
Published: January 2020

We studied isolates from 73 patients hospitalized with typhoid fever in Lima, Peru. Of these 73 patients, 11 (15%) suffered a clinical relapse, with fever and positive blood cultures, within 3 months of their original illness. Using plasmids as epidemiologic markers, we found that three patients who subsequently relapsed were initially infected with more than one strain of Salmonella typhi. There was a highly significant association between relapse and isolation of a strain containing either a 24- or a 38-kilobase plasmid at the time of the original infection; however, we were unable to show any evidence of homology between these two plasmids. Our data indicate that infection with multiple strains is not uncommon in this endemic area and suggest that relapse may be partly strain dependent.
Meningitis caused by vancomycin-resistant Leuconostoc sp
Authors: Coovadia Y M , Solwa Z , van den Ende J
Published: January 2020

A rare case of purulent meningitis caused by vancomycin-resistant Leuconostoc sp. is reported. The patient was treated successfully with penicillin G, and there were no neurological sequelae. We recommend that all gram-positive cocci isolated from cerebrospinal fluid and blood be fully identified so as not to confuse Leuconostoc spp. with more commonly isolated pathogens such as pneumococci and other alpha-hemolytic streptococci.
Streptococcal group B type antigen X in group L streptococci
Authors: Lämmler C , Gürtürk K , Blobel H
Published: January 2020

Extracts from 19 of 29 group L streptococcal cultures reacted distinctly with antiserum against group B streptococcal type antigen X in coagglutination and immunodiffusion tests. The X antigen corresponded to those obtained by streptococci of serological groups B and G.
Problems in identification of Campylobacter jejuni associated with acquisition of resistance to nalidixic acid
Authors: Altwegg M , Burnens A , Zollinger-Iten J , Penner J L
Published: January 2020

In a patient with campylobacteriosis, we observed development of resistance to nalidixic acid and norfloxacin under adequate treatment with the latter antibiotic. Isolates before and after treatment differed in their total protein profile but were otherwise identical with respect to enzymatic activity, serotype, crude membrane protein profiles, and other phenotypic characteristics.
Quantification of immunoglobulin on electrophoretic immunoblot strips as a tool for human immunodeficiency virus serodiagnosis
Authors: Blomberg J , Klasse P J
Published: January 2020

Electrophoretic immunoblotting (EIB [Western blotting]), the main method for verification of human immunodeficiency virus (HIV) seropositivity, needs thorough characterization and standardization. We explored the possibilities of quantifying immunoglobulin G (IgG) bound to EIB strips both by densitometry of the peroxidase-stained bands and by measurement of radioactivity with labeled anti-HIV IgG. The radioactivity method is inherently more exact but was more cumbersome. However, despite saturation phenomena at high IgG densities, the densitometric method was more convenient and yielded reproducible estimates of the amount of bound IgG. We found it useful primarily for documentation of changes in the relative abundance of antibodies to different HIV proteins from individual patients over time. To explore the potential usefulness of the method, we studied a small set of HIV-seropositive persons. The average p24/gp41 color yield ratios and standard deviations in 3 persons with recent seroconversion, 15 healthy subjects, and 6 diseased HIV-seropositive persons were 6.6 +/- 0.9, 2.3 +/- 1.9, and 1.3 +/- 0.5, respectively. These data are in accord with previous qualitative or semiquantitative observations but are too limited for any conclusions regarding the use of quantitative EIB for prognostic use with individual patients. Quantitative EIB is a valuable tool for comparative methodological studies and for research on the protective role of anti-HIV antibodies in acquired immunodeficiency syndrome pathogenesis. Its possible use in prognostication for individual patients must be evaluated in long-term studies.
Criteria for disk susceptibility tests and quality control guidelines for the cefoperazone-sulbactam combination
Authors: Barry A L , Jones R N
Published: January 2020

For in vitro susceptibility tests with cefoperazone and sulbactam (a beta-lactamase inhibitor), 75/30-micrograms disks may be used with the interpretive zone size breakpoints that are currently used for 75-micrograms cefoperazone disks. For dilution tests, a 2:1 ratio of cefoperazone to sulbactam is recommended. For quality control purposes, MIC limits that are used to monitor cefoperazone tests were also applied to tests with the combination of drugs. For gram-negative control strains, zone size limits were calculated to be 1 mm smaller than those used for cefoperazone disks. To monitor the sulbactam portion of the combination, Acinetobacter calcoaceticus subsp. anitratus ATCC 43498 was selected; zones with 75/30-micrograms disks were 26 to 32 mm in diameter, and broth microdilution MICs ranged from 1.0/0.5 to 8.0/4.0 micrograms/ml. With cefoperazone alone, MICs for Acinetobacter calcoaceticus subsp. anitratus were 16 to 64 micrograms/ml and zones ranged from 14 to 18 mm in diameter. For anaerobic dilution tests, only Bacteroides thetaiotaomicron ATCC 29741 is recommended for cefoperazone-sulbactam; MICs ranged from 8.0/4.0 to 32/16 micrograms/ml.
Predominance of the ac variant in K88-positive Escherichia coli isolates from swine
Authors: Westerman R B , Mills K W , Phillips R M , Fortner G W , Greenwood J M
Published: January 2020

Monoclonal antibodies to K88ac and K88ab were used in enzyme-linked immunosorbent assays on Escherichia coli cultures known to produce K88 pili. A total of 415 K88-positive E. coli isolates from nine states were all found to be the K88ac variant. The cultures tested were isolated during the years 1976 to 1985.
Mesenteric lymphadenitis of swine caused by Rhodococcus sputi
Authors: Tsukamura M , Komatsuzaki C , Sakai R , Kaneda K , Kudo T , Seino A
Published: January 2020

Rhodococcus sputi caused tuberculosislike lymphadenitis of mesenteric lymph nodes in swine. This is the first study reporting that R. sputi can be a pathogen in swine.
Polyacrylamide gel electrophoresis and silver staining for detection of rotavirus in stools from diarrheic patients in Thailand
Authors: Kasempimolporn S , Louisirirotchanakul S , Sinarachatanant P , Wasi C
Published: January 2020

Detection of rotavirus by polyacrylamide gel electrophoresis in combination with silver staining and by enzyme-linked immunosorbent assay showed 96.7% identical results in tests with 1,304 stool specimens from diarrheic patients. The polyacrylamide gel electrophoresis method can be modified to reduce cost and working time. Phenol extraction of stools, however, is essential in maintaining the sensitivity of the method.
Detection of herpes simplex virus in conventional tube cell cultures and in shell vials with a DNA probe kit and monoclonal antibodies
Authors: Espy M J , Smith T F
Published: January 2020

Specimens submitted for diagnosis of herpes simplex virus (HSV) infection were inoculated into shell vials and reacted with a commercial DNA probe kit (Pathogene; Enzo Biochem, Inc., New York, N.Y.) and an immunofluorescence assay at 16 h postinoculation. The results were compared with isolation of the virus in conventional tube cell cultures. Of 504 specimens, 105 (20.8%) were positive for HSV. Of the 105, 93 HSV-positive specimens (89%) were detected by all three assay systems. Maximum detection of HSV (100 of 105 [95%]) was obtained by probe or monoclonal antibody assay in shell vials, which had sensitivities of 98 and 97%, respectively, compared with viral recovery in conventional tube cell cultures (mean time for recognition of cytopathic effects, 2 days). Both shell vial assays were 99% specific. The DNA probe kit may be used as an alternative to a monoclonal antibody and fluorescence assay in shell vials as a diagnostic method for rapid laboratory detection of HSV infection.
Quantitation of effects of subinhibitory concentrations of trimethoprim on P fimbria expression and in vitro adhesiveness of uropathogenic Escherichia coli
Authors: Dean E A , Kessler R E
Published: January 2020

The ability to adhere to and colonize urogenital mucosa is an important virulence attribute of uropathogenic Escherichia coli. This adherence, which appears to be mediated by P fimbriae, may be affected by antibiotics or other agents that affect fimbrial expression. We describe here an enzyme immunofiltration assay to quantitate fimbriation and the application of that technique to measurement of the effects of sublethal doses of trimethoprim on P fimbrial expression. Effects on P fimbriation correlated with effects on the adherence of treated bacteria to cultured T24 bladder carcinoma epithelial cells; i.e., trimethoprim treatment decreased both P fimbriation and bacterial adherence. It was possible to quantitate effects on P fimbriation when type 1 fimbriae were also present. The enzyme immunofiltration assay may be useful for studies on the role of fimbriae in the pathogenesis of bacterial infections, and it may facilitate identification of antimicrobial agents that interfere with bacterial adherence to mucosal surfaces.
Prevalence of capsular polysaccharide types 5 and 8 among Staphylococcus aureus isolates from cow, goat, and ewe milk
Authors: Poutrel B , Boutonnier A , Sutra L , Fournier J M
Published: January 2020

Monoclonal antibodies to Staphylococcus aureus capsular polysaccharide types 5 and 8 were used to serotype by enzyme-linked immunosorbent assay 212, 54, and 33 isolates from cow, goat, and ewe milk, respectively. Capsular types 5 and 8 accounted for 69.4% of bovine isolates and 71.5 and 78.8% of goat and ewe isolates, respectively. Type 5 was predominant in strains from bovine sources (51.4%), whereas type 8 was prevalent in strains from caprine (68.5%) and ovine (75.8%) sources.
Immunoblots and plasmid fingerprints compared with serotyping and polyacrylamide gel electrophoresis for typing Clostridium difficile
Authors: Mulligan M E , Peterson L R , Kwok R Y , Clabots C R , Gerding D N
Published: January 2020

Two new methods for typing Clostridium difficile, immunoblotting and plasmid fingerprinting, were compared with serotyping and polyacrylamide gel electrophoresis (PAGE). Of these methods, immunoblotting was found to be the most valuable for use in a comprehensive typing system. More groups could be distinguished by immunoblotting than by serotyping or PAGE. Immunoblotting results were also more reproducible and distinctive than results by PAGE. Plasmid fingerprinting was an excellent marker for plasmid-bearing strains, but it had limited use because many isolates lacked plasmids. A unique plasmid profile observed for one group of isolates correlated with differences in phenotypic characteristics resolved by immunoblot analysis but not by serotyping or PAGE. Preliminary attempts to correlate typing results with pathogenicity of isolates were not successful but underscored the need for future studies to include careful assessment of the clinical significance of isolates.
Identification of major slowly growing pathogenic mycobacteria and Mycobacterium gordonae by high-performance liquid chromatography of their mycolic acids
Authors: Butler W R , Kilburn J O
Published: January 2020

A rapid, reverse-phase high-performance liquid chromatography method was used to detect rho-bromophenacyl mycolic acid ester patterns for strains of four major pathogenic Mycobacterium species and for the most commonly encountered saprophytic species, Mycobacterium gordonae. Mycobacteria in low numbers (2.5 X 10(6) CFU) were detected and identified to the species level. Standard chromatographic patterns characteristic of each species were established. Simple pattern recognition enabled rapid identification of M. tuberculosis, M. kansasii, M. avium, M. intracellulare, and M. gordonae.
DNA homology and immunological cross-reactivity between Aeromonas hydrophila cytotonic toxin and cholera toxin
Authors: Schultz A J , McCardell B A
Published: January 2020

DNA colony hybridization with three 18- to 20-base-long synthetic oligonucleotide probes for cholera toxin (CT) was used to screen 12 clinical isolates of Aeromonas hydrophila. Under stringent hybridizing (overnight at 40 degrees C) and washing (1 h at 50 degrees C) conditions, nine strains reacted with the 32P-labeled CT probes. Concentrated (10x) cell-free supernatants or lysates from eight cultures, heated at 56 degrees C for 20 min, produced cytotonic effects in Y-1 mouse adrenal cells and Chinese hamster ovary (CHO) cells and caused a 1.5- to 22-fold increase in production of cyclic AMP in CHO cells. Preincubation with anti-CT reduced the CHO cell titer of cell lysates by 10-fold. In the GM1 ganglioside enzyme-linked immunosorbent assay, heated supernatants and lysates gave readings equivalent to 3.5 to 100 ng of CT. Three proteins with molecular weights of 89,900, 37,000, and 11,000 reacted with anti-CT on immunoblots of cell lysates from sodium dodecyl sulfate-polyacrylamide gels. These results suggest that there is DNA homology and immunological cross-reactivity between CT and the A. hydrophila cytotonic toxin.