bluuebunny/crossref_metadata_2025 huggingface dataset:
Postoperative infant septicemia caused by Pseudomonas luteola (CDC group Ve-1) and Pseudomonas oryzihabitans (CDC group Ve-2)
Authors: Freney J , Hansen W , Etienne J , Vandenesch F , Fleurette J
Published: January 2020

Pseudomonas luteola (CDC group Ve-1) and Pseudomonas oryzihabitans (CDC group Ve-2) were both isolated from the same blood culture of a 5-month-old infant, 8 days after open-heart surgery. He quickly responded to appropriate antibiotics. Carbon substrate assimilation tests and fatty acid analysis clearly differentiated these two rarely pathogenic organisms.
Evaluation of in vitro methods for testing susceptibility of anaerobes to ampicillin-sulbactam and amoxicillin-clavulanic acid
Authors: Fuchs P C , Barry A L , Jones R N
Published: January 2020

A total of 97 anaerobic bacteria were tested for susceptibility to ampicillin, ampicillin-sulbactam, and amoxicillin-clavulanic acid by broth microdilution and disk elution methods, the results of which were compared with those of the reference agar dilution method. With the broth microdilution method, approximately 95% of MICs were within 1 dilution of those of the reference agar method, with a definite (0.6 to 0.7 dilution) trend toward lower MICs. The disk elution test performed satisfactorily, but additional anaerobic isolates resistant to ampicillin-sulbactam and/or amoxicillin-clavulanic acid (currently rare) are needed to assure the predictability of resistance by the disk elution test.
Rapid diagnosis of influenza A and B by 24-h fluorescent focus assays
Authors: Stokes C E , Bernstein J M , Kyger S A , Hayden F G
Published: January 2020

Murine monoclonal antibodies directed against type-specific antigens of influenza A and B viruses have been shown to be useful diagnostic reagents for the detection of influenza viruses by immunofluorescence testing of nasopharyngeal cells. We have developed fluorescent focus assays utilizing these antibodies in cell culture chamber slides and shell vials for the rapid diagnosis of influenza A and B. Chamber slide assays were compared with virus isolation in 160 specimens from 135 patients with symptoms of influenza. Virus isolation was compared with immunofluorescence testing in 38 of the 160 specimens. Compared with virus isolation, 24-h cell culture chamber slide assays had a sensitivity of 75% and a specificity of 96%. Immunofluorescence testing of nasopharyngeal cells was only 38% sensitive and 91% specific. Shell vial assays were compared with virus isolation for 89 specimens. At 16 to 18 h postinoculation, the shell vial assay was 84% sensitive and 100% specific. We conclude that both chamber slide and shell vial assays are rapid, sensitive, and specific techniques for the diagnosis of influenza.
Detection of bacteria by hybridization of rRNA with DNA-latex and immunodetection of hybrids
Authors: Miller C A , Patterson W L , Johnson P K , Swartzell C T , Wogoman F , Albarella J P , Carrico R J
Published: January 2020

A novel nucleic acid hybridization assay with a DNA probe immobilized on 1.25-micron-diameter latex particles was developed. Hybridization of the immobilized probe DNA with sample rRNA was complete in 10 to 15 min. Alkaline phosphatase-labeled anti-DNA-RNA was allowed to bind to the DNA-RNA hybrids on the latex particles. Then the latex was collected on a small glass fiber filter pad, and bound alkaline phosphatase was quantitated by reflectance rate measurement. The method detected a broad range of bacterial species and had a detection limit of 500 cells per assay. The assay was used to screen urine samples for bacteriuria and had a sensitivity of 96.2% compared with conventional culture at a decision level of greater than or equal to 10(4) CFU/ml. The hybridization method could have broad application to the detection of bacteria and viruses.
Staphylococcal scalded skin syndrome in two immunocompetent adults caused by exfoliatin B-producing Staphylococcus aureus
Authors: Opal S M , Johnson-Winegar A D , Cross A S
Published: January 2020

An exfoliatin B-producing strain of Staphylococcus aureus was isolated from two adults with typical staphylococcal scalded skin syndrome (SSSS). One patient developed desquamation after a local staphylococcal infection of the hand, and the other developed exfoliation after nosocomially acquired staphylococcal endocarditis. Neither patient was immunocompromised, had evidence of renal insufficiency, or manifested other potential risk factors for SSSS. Purified toxin, isolated from the causative organisms, produced a Nikolsky sign in neonatal mice. The toxins were shown to be exfoliatin B by biochemical and immunologic methods and heretofore had been described only in children with SSSS. Analysis of plasmid DNAs from both strains revealed a 23-megadalton plasmid with identical restriction endonuclease digestion fragments. One isolate belonged to phage group II (3B/3C/6/7/47/54/55), whereas the other isolate belonged to phage groups I and III (7/29/52/52A/53/54/80). The observation that a non-phage group II exfoliatin-producing strain of S. aureus may produce SSSS in adults indicates the need to better define the diagnostic criteria for SSSS. Immunocompetent adults may remain susceptible to some strains of exfoliatin B-producing S. aureus.
Sensitivity of rhabdomyosarcoma and guinea pig embryo cell cultures to field isolates of difficult-to-cultivate group A coxsackieviruses
Authors: Lipson S M , Walderman R , Costello P , Szabo K
Published: January 2020

Forty-two difficult-to-cultivate group A coxsackieviruses (i.e., group A types other than A7, A9, and A16), collected primarily from throat swab specimens of patients suffering from fever, pharyngitis, lymphadenopathy, and cough during the 1986 enterovirus season, were isolated in less than 24-h-old suckling mice. Thirty-six moribund mice were sacrificed and autopsied, and then their brains and back musculature were inoculated into rhabdomyosarcoma (RD), guinea pig embryo (GPE), rhesus monkey kidney (RhMk) and human carcinoma of the larynx (HEp-2) cell cultures. Twelve of the 36 suckling mice isolates were adapted to grow in RD and GPE cells after two passes and have been identified in RD cells by type-specific antisera as group A coxsackievirus types A2, A4, and A8. Three passes in RhMk or HEp-2 cell cultures were insufficient to affect a discernible cytopathic effect. Coxsackievirus types A1, A19, and A22, unable to grow in any of the four cell cultures tested, were identified by virus neutralization in suckling mice. These data denote the efficacy of suckling mice for the isolation of difficult-to-cultivate group A coxsackieviruses.
Entamoeba histolytica antigen-specific induction of human immunodeficiency virus replication
Authors: Croxson S , Mildvan D , Mathews H , Poiesz B J
Published: January 2020

Replication of human immunodeficiency virus (HIV) may be initiated in infected lymphocytes by antigenic or mitogenic stimulation. A soluble protein derived from an invasive strain of Entamoeba histolytica (amoebic antigen [AA]) was used to study the lymphoblastic responses of T lymphocytes derived from 8 HIV-seronegative homosexual men (controls) and 15 HIV-seropositive homosexual men (patients). The soluble protein was also used in long-term cultures as a stimulus for HIV replication. No control or patient produced detectable lymphoblastic responses to AA in a 6-day tritiated-thymidine incorporation assay. Of 15 patients, 5 (33%) produced HIV p24 (ranging from 31 pg/ml to 151 ng/ml) in response to AA in 30-day cell cultures. HIV p24 was expressed in three of seven patients in response to AA but not to the T-lymphocyte mitogen phytohemagglutinin. Implications for managing HIV-infected patients are discussed.
New, practical approach to detecting antibody to pertussis toxin for public health and clinical laboratories
Authors: Wong K H , Skelton S K
Published: January 2020

A new, practical method for determining antibody to pertussis toxin (PT) by enzyme-linked immunosorbent assay for public health and clinical laboratories is possible because of recent advances in understanding the pathobiology of Bordetella pertussis and the physicochemical properties of PT. The new approach does not require the use of highly purified PT antigen, which is difficult and expensive for most laboratories to obtain. Moreover, it employs only reagents that are commercially readily available. The method combines the purification of PT antigen and an assay for PT antibody into one process. It depends on (i) growth of B. pertussis in a simple, defined medium to obtain a PT-rich supernatant with little contamination of cellular antigens; (ii) a simple, one-step concentration of PT in the culture supernatant with Affi-Gel Blue (Bio-Rad Laboratories, Richmond, Calif.); and (iii) specific adsorption of PT as the test antigen to microtiter wells coated with fetuin for the enzyme-linked immunosorbent assay. The procedure is sensitive and specific for PT antibody. It is technically simple, reproducible, and can be performed in a modestly equipped laboratory.
Improvement of a direct agglutination test for field studies of visceral leishmaniasis
Authors: el Harith A , Kolk A H , Leeuwenburg J , Muigai R , Huigen E , Jelsma T , Kager P A
Published: January 2020

To increase the potential for the wide-scale application of our direct agglutination test for visceral leishmaniasis, modifications in the components and procedures were introduced. Supplementation with 0.056 M citrate of the suspension medium stabilized the antigen for 9 weeks at 37 degrees C. To circumvent the need for cooling systems in the field, 0.2% (wt/vol) gelatin was added to the serum diluent instead of fetal bovine serum, with reliable results. Specificity and sensitivity were improved by the incorporation of 0.1 M 2-mercaptoethanol in samples with borderline titers. The test could be performed on samples of whole blood; thus the difficulties of preparation and storage of serum, plasma, or filter paper blood are avoided. For mass screening programs, a single serum dilution of 1:6,400 could be employed, contributing to a further reduction in test expenses. Sera from different geographical areas showed equal reactivities in this direct agglutination test despite the nonhomologous Leishmania donovani antigens used.
Enzyme-linked immunosorbent assay for detection of leukocidin toxin from Staphylococcus aureus in bovine milk samples
Authors: Loeffler D A , Creasy M T , Norcross N L , Paape M J
Published: January 2020

An enzyme-linked immunosorbent assay was developed for the detection of leukocidin toxin from Staphylococcus aureus. The minimum concentration of leukocidin detectable with the assay was 30 ng/ml. The enzyme-linked immunosorbent assay was found to be a more sensitive method, by a mean of 45-fold, for leukocidin detection than was observation of cytolytic effects of the toxin on bovine neutrophils. A mean toxin concentration of 974 ng/ml was required to produce observable cytolytic effects on neutrophils. Although the enzyme-linked immunosorbent assay was able to detect leukocidin in milk samples from toxin-infused mammary glands, the toxin was detectable in only 2 of 27 S. aureus-infected milk samples (7%) from cows with chronic staphylococcal mastitis. To determine whether leukocidin antibodies in the mastitic milk samples were preventing toxin detection, leukocidin was mixed with milk with a high antileukocidin antibody titer (from a vaccinated cow) and evaluated with the immunoassay. Leukocidin was readily detected in this sample, indicating that milk antileukocidin antibodies were not sufficient to prevent detection of any leukocidin present in the mastitic milk samples. Failure to detect leukocidin in most mastitic milk samples with this assay indicated that, if leukocidin is produced in the bovine mammary gland during chronic staphylococcal mastitis, the concentration of the toxin may be too low to produce cytolytic effects on neutrophils.
Evaluation of several commercial biochemical and immunologic methods for rapid identification of gram-positive cocci directly from blood cultures
Authors: Rappaport T , Sawyer K P , Nachamkin I
Published: January 2020

To develop laboratory methods for the rapid identification of gram-positive cocci from blood cultures, several commercial immunological and biochemical tests for identifying staphylococci and streptococci from two different blood culture systems (Thiol/TSB, Difco Laboratories; BACTEC, Johnston Laboratories, Inc.) were evaluated and compared with conventional identification methods. A total of 44 cultures contained Staphylococcus aureus as determined by conventional methods. Commercial immunological methods (six tested) ranged in overall sensitivity from 38.6 (Staphyloslide; BBL Microbiology Systems) to 77.3% (Staphaurex; Wellcome Diagnostics). All methods tested had 100% specificity. A total of 30 isolates of group D streptococci were tested with immunological and biochemical identification systems. The overall sensitivity ranged from 14.2% (Phadebact Group D; Pharmacia Diagnostics) to 100% with Streptex (Wellcome; immunological) and Identicult A-E (Scott Laboratories, Inc.; biochemical). The results of this study suggest that some reagents can be used to provide rapid identification of gram-positive cocci from blood cultures 24 h earlier than standard methods.
Use of monoclonal antibodies to identify the distribution of A and M epitopes on smooth Brucella species
Authors: Douglas J T , Palmer D A
Published: January 2020

The smooth types of Brucella species express two lipopolysaccharides (LPSs) (A and M) which are antigenically distinct. Their existence as cross-reactive antigenic complexes makes definitive serology difficult. Murine hybridomas were produced and selected for their ability to produce monoclonal antibodies to the specific A- or M-LPS epitopes. The specificity of the monoclonal antibodies was determined by microplate enzyme-linked immunoassay, binding inhibition assay, microplate agglutination, and dot blot assay. Monoclonal antibody 12AE6 was specific for an epitope on the A LPS of Brucella spp., which was also expressed on Yersinia enterocolitica O:9. A unique epitope of M LPS was detected by monoclonal antibody 33.1.5. The two monoclonal antibodies did not exhibit cross-reactions when assayed with whole Brucella cells or purified M- and A-LPS preparations. Cross-reactive serology with polyvalent sera can be attributed to the presence of common antigenic determinants on both molecules. The use of A- and M-LPS-specific monoclonal antibodies has the potential to replace the more laborious methods involved in the production of monospecific sera.
Evaluation of a rapid urease test to detect Campylobacter pylori infection
Authors: Westblom T U , Madan E , Kemp J , Subik M A
Published: January 2020

Seventy-five consecutive patients referred for upper gastrointestinal tract endoscopy were evaluated for Campylobacter pylori infection by pathology, culture, and a biochemical test to detect bacterial urease. Forty-eight patients (64%) had C. pylori present based on pathology or culture or both. Thirty-two urease tests were positive after 1 h, all in patients with C. pylori detected by the two other methods (specificity, 100%; sensitivity, 67%). After 24 h, 47 urease tests were positive, but only 40 had C. pylori present (specificity, 74%; sensitivity, 83%). When read after 1 h, the urease test was highly specific and led to rapid presumptive diagnosis.
Determination of patient herpes simplex virus immune status by latex agglutination
Authors: Gleaves C A , Meyers J D
Published: January 2020

A rapid latex agglutination (LA) test was compared with complement fixation and enzyme immunoassay for the determination of herpes simplex virus immune status in sera of patients. Of 173 samples, 88% gave concordant results in all three assays (115 positive and 37 negative). The LA and complement fixation tests agreed 92% of the time, and the LA agreed with the enzyme immunoassay 94% of the time. LA is a simple and rapid test which can be used for determining the herpes simplex virus immune status in sera of patients.
Evaluation of a direct identification method for Staphylococcus aureus from blood culture broth
Authors: Hamoudi A C , Hribar M M
Published: January 2020

We evaluated the reliability of Staphaurex (Wellcome Diagnostics, Dartford, England) for the direct identification of staphylococci from blood culture broth with evidence of positivity and a suggestive Gram-stained smear. Our evaluation indicates that this application is of limited sensitivity, thus reducing the value of a negative test. However, since the test is highly specific, a positive test is significant in predicting the isolation of Staphylococcus aureus.
Differentiation of toxigenic from nontoxigenic isolates of Pasteurella multocida by enzyme-linked immunosorbent assay
Authors: Foged N T , Nielsen J P , Pedersen K B
Published: January 2020

An enzyme-linked immunosorbent assay (ELISA) was developed for the rapid and simple differentiation of toxigenic from nontoxigenic strains of Pasteurella multocida. The sandwich ELISA is based on two different murine monoclonal antibodies with specificity for the P. multocida toxin. The ELISA, which is now used as a routine test in Denmark, has several advantages compared with previously described biological tests.
Virulence of Escherichia coli in relation to host factors in women with symptomatic urinary tract infection
Authors: Sandberg T , Kaijser B , Lidin-Janson G , Lincoln K , Orskov F , Orskov I , Stokland E , Svanborg-Edén C
Published: January 2020

The relationship between bacterial characteristics and the severity of urinary tract infection in adults has not been clarified. In this study, Escherichia coli strains (n = 178) were prospectively collected from women with community-acquired urinary tract infection. The isolates were identified by O:K:H serotype and characterized for adherence, hemolysin production, and serum bactericidal resistance. The patients had acute pyelonephritis with or without complicating factors and acute cystitis. Nine serotypes (O1:K1:H7, O1:K1:H-, O2:K1:H-, O4:K12:H1, O7:K1:H-, O9:K34:H-, O16:K1:H6, O16:K1:H-, and O75:K5:H-) comprised 65% of the strains in uncomplicated pyelonephritis, but were significantly less often encountered in complicated pyelonephritis or cystitis. Adherence was the single property most characteristic of the pyelonephritogenic clones. Adhesins specifically recognizing Gal alpha 1----4Gal beta-containing receptors occurred in 80% of strains in uncomplicated pyelonephritis, in 50% of strains in complicated infections, and in 37% of cystitis strains. Hemolysin production and serum resistance did not correlate with any disease pattern. Advanced age did not seem to reduce the selection of virulent E. coli to cause pyelonephritis. These results demonstrate in women a relationship between E. coli virulence and the severity of urinary tract infection analogous to that previously observed in pediatric populations and also illustrate the balance between host resistance and bacterial virulence in the urinary tract.
Ticks and biting insects infected with the etiologic agent of Lyme disease, Borrelia burgdorferi
Authors: Magnarelli L A , Anderson J F
Published: January 2020

Members of 18 species of ticks, mosquitoes, horse flies, and deer flies were collected in southeastern Connecticut and tested by indirect fluorescent-antibody staining methods for Borrelia burgdorferi, the etiologic agent of Lyme disease. An infection rate of 36.2% (116 tested), recorded for immature Ixodes dammini, exceeded positivity values for all other arthropod species. Prevalence of infection for hematophagous insects ranged from 2.9% of 105 Hybomitra lasiophthalma to 14.3% of seven Hybomitra epistates. Infected I. dammini larvae and nymphs coexisted with infected Dermacentor variabilis (American dog tick) immatures on white-footed mice (Peromyscus leucopus), but unlike I. dammini, none of the 55 adult American dog ticks collected from vegetation harbored B. burgdorferi. Groups of 113 field-collected mosquitoes of Aedes canadensis and 43 Aedes stimulans were placed in cages with uninfected Syrian hamsters. Of these, 11 females of both species contained B. burgdorferi and had fed fully or partially from the hamsters. No spirochetes were isolated from the hamsters, but antibodies were produced in one test animal.
Occurrence of mucoid M-18 Streptococcus pyogenes in a central Ohio pediatric population
Authors: Marcon M J , Hribar M M , Hosier D M , Powell D A , Brady M T , Hamoudi A C , Kaplan E L
Published: January 2020

During a 1-year period from October 1986 through September 1987, we recovered 116 mucoid, hemolytic Streptococcus pyogenes isolates from clinical specimens collected from patients seen at our pediatric institution. A total of 102 isolates were from throat cultures (101 for pharyngitis, 1 for acute rheumatic fever), 13 were from other superficial body sites, and 1 was from pleural fluid. All of 40 mucoid isolates tested to date were determined to be M-type 18 strains. A direct latex agglutination test for group A carbohydrate antigen in throat swab specimens was equally sensitive in detecting M-18 mucoid and nonmucoid strains (45 of 77 [58%] and 795 of 1,186 [67%], respectively; not significant, P greater than 0.05). Antimicrobial susceptibility tests performed with 40 mucoid and 40 nonmucoid isolates against penicillin and nine other antimicrobial agents showed all strains to be susceptible, with no difference in MICs. All isolates tested were also considered fully susceptible to the bactericidal activity of penicillin. Further studies are needed to establish the relative virulence of M-18 strains and their possible association with the resurgence of acute rheumatic fever in central Ohio and other areas of the United States.
Prediction and diagnosis of early Pseudomonas aeruginosa infection in cystic fibrosis: a follow-up study
Authors: Brett M M , Ghoneim A T , Littlewood J M
Published: January 2020

Immunoglobulin G (IgG) antibodies to Pseudomonas aeruginosa surface antigens in serum were estimated by enzyme-linked immunosorbent assay for all patients from whom P. aeruginosa was isolated for the first time during a study period of 3 years (33 patients). The titer of IgG antibodies was greater than control values at or up to 24 months before the first isolation of P. aeruginosa in 24 patients. Another five patients had titers that were within the control range before isolation of P. aeruginosa but increased to above the control range within the following 2 months. In these 29 patients, continuing intermittent isolations of P. aeruginosa were accompanied by further increases in titer. The presence of a systemic immune response above the control range indicates tissue invasion and hence infection. Four patients were deemed to have no infection: one or two isolations of P. aeruginosa were accompanied by no increase in specific antibodies to above the control range throughout the entire study period. Fifteen patients received intravenous antipseudomonal chemotherapy. Eradication of the organism and a return of titer to control values, suggesting complete removal of the organisms, occurred in 5 patients, while continued isolations and only a partial decrease in titer occurred in 10 patients. The 15 patients who received treatment improved clinically, in contrast to untreated patients, whose clinical state worsened during the study period. Continuous steroid treatment, given to two patients, was accompanied by a dramatic decrease in both serum IgG concentration and titer, despite continuing intermittent isolations of P. aeruginosa. These results confirm and extend our earlier finding that this assay appears to detect P. aeruginosa infection at a very early stage and helps in differentiating between early infection and harmless colonization. It also appears to be a useful monitor of the progress of infection and the response to intravenous antibiotic treatment in these early stages of infection, before any clinical changes are sufficiently large to be detected, in patients who were not on continuous steroid therapy. The effect of steroid treatment on the immunological response and clinical outcome of patients with early P. aeruginosa infection requires further investigation.
Plasmid, serotypic, and enterotoxin analysis of Bacillus cereus in an outbreak setting
Authors: DeBuono B A , Brondum J , Kramer J M , Gilbert R J , Opal S M
Published: January 2020

Bacillus cereus is a recognized agent of food-borne disease. In this report we describe an outbreak of B. cereus gastroenteritis associated with consumption of beef stew among patients and staff at a Rhode Island nursing home. The beef had been improperly stored after preparation. The predominant symptoms of the illness were cramps and diarrhea; it lasted an average of 16 h. No deaths occurred. The organism was recovered from 10 of 23 stools collected from ill patients and 1 of 21 stools collected from controls (P = 0.0044, Fisher's two-tailed exact test). All isolates had the same biotype and serotype, newly designated H.26; all elaborated the diarrheal B. cereus enterotoxin when tested in rabbits by the vascular permeability reaction; and all had identical plasmid profiles, which differed from those of B. cereus strains selected randomly from other outbreaks. Plasmid analysis may prove to be a useful new tool in investigating outbreaks of B. cereus food poisoning.
Formalin-inactivated respiratory syncytial virus vaccine induces antibodies to the fusion glycoprotein that are deficient in fusion-inhibiting activity
Authors: Murphy B R , Walsh E E
Published: January 2020

The fusion (F) glycoprotein of respiratory syncytial virus (RSV) induces neutralizing antibodies and antibodies that inhibit fusion of infected cells (FI antibody). It was previously shown that infants and children immunized with Formalin-inactivated RSV 20 years ago developed antibodies that bound to the F glycoprotein but were deficient in neutralizing activity. A reexamination of these sera indicated that they were also deficient in FI activity. Thus, Formalin-inactivated RSV vaccine stimulated an unbalanced immune response in which an unusually large proportion of the induced antibodies were directed against nonprotective epitopes rather than against the epitopes that induce functional antibodies, i.e., neutralizing and FI antibodies. This deficiency in stimulation of functional antibodies probably decreased the protective efficacy of the vaccine and could have contributed to potentiation of disease in the vaccines during subsequent RSV infection.
Progress in culture and subculture of spheroplasts and fastidious acid-fast bacilli isolated from intestinal tissues
Authors: Markesich D C , Graham D Y , Yoshimura H H
Published: January 2020

The efficiency of culture media was compared for the culture and subculture of very slowly growing acid-fast bacilli and spheroplast forms obtained from intestinal tissues of patients with Crohn's disease and ulcerative colitis and from controls without inflammatory bowel disease. Media were developed by modifying a nutrient broth medium based on veal infusion broth and yeast extract. We evaluated the effects of pH and the addition of Tween 80, Dubo oleic albumin complex, an extract from intestinal tissue from a patient with Crohn's disease, horse serum, sucrose, magnesium sulfate, ferrous ammonium sulfate, and sodium citrate. All media contained mycobactin J (2 micrograms/ml). We developed a medium (MG3) which was highly successful in promoting the growth of very fastidious organisms and promoted reversion of spheroplasts to acid-fast rods. MG3 contained veal infusion broth, 1% yeast extract, 10% horse serum, 0.3 M sucrose, 0.2% MgSO4, 0.1% ferrous ammonium sulfate, 0.1% sodium citrate, and 2 mg of mycobactin J per liter. We were able to obtain quantities of organisms sufficient for examination of the organisms by molecular techniques. Successful cultivation of all isolates and reversion of spheroplasts to acid-fast forms encourage further studies of the possibility of a complex association of mycobacteria and Crohn's disease.
Routine evaluation of BACTEC NR-16A and NR-17A media
Authors: Courcol R J , Durocher A V , Roussel-Delvallez M , Fruchart A , Martin G R
Published: January 2020

The purpose of this study was to determine whether the BACTEC NR-16A and NR-17A media were more effective than the BACTEC NR-6A and NR-7A media in recovering organisms from the blood of patients undergoing antimicrobial therapy. A total of 986 sets of four blood culture bottles were compared, giving 141, 174, 93, and 104 isolates with BACTEC NR-6A, NR-16A, NR-7A, and NR-17A, respectively. BACTEC NR-6A and NR-7A media recovered 234 isolates, whereas BACTEC NR-16A and NR-17A media recovered 278 isolates. The recovery rate of bacteria when aerobic resin media were used was better than that with conventional aerobic media (P less than 0.001). The mean detection times were 51.5 and 69.7 h with NR-16A and NR-6A, respectively (P less than 0.01), whereas they were 68.2 and 71.3 h with NR-17A and NR-7A, respectively (P greater than 0.05). The small number of anaerobes recovered precluded a statistical comparison of relative recovery for that group of organisms.
Comparison of nine commercial immunoassays for the detection of rotavirus in fecal specimens
Authors: Dennehy P H , Gauntlett D R , Tente W E
Published: January 2020

One hundred fecal specimens obtained from patients with acute gastroenteritis were tested for rotavirus with nine commercial immunoassays to evaluate the sensitivity, specificity, predictive value, and diagnostic accuracy of these assays. Kits evaluated included two monoclonal antibody-based enzyme immunoassays (EIAs) (Rotaclone and Pathfinder Rotavirus), three polyclonal antibody-based EIAs (Rotavirus Immunoassay, Rotazyme II, and Wellcozyme Rotavirus), and four latex agglutination assays (Rotastat, Virogen Rotatest, Meritec-Rotavirus, and The Wellcome Latex Test). Thirty-eight of the 100 specimens were found to contain rotavirus by a reference microplate EIA. The accuracy of the reference assay was determined by RNA electrophoresis and a blocking assay on discordant specimens. The two monoclonal antibody EIAs had superior sensitivities (100%) and identified two positive specimens which were negative by the reference method but positive by the blocking assay. Among the polyclonal EIAs, all had sensitivities of greater than 90%, but specificities were variable; Rotazyme II, with a specificity of 50%, showed considerable discrepancy from other polyclonal EIAs. The latex tests had sensitivities ranging from 70 to 90% and specificities of 80 to 100%. Latex agglutination tests were more rapid than EIAs and did not require expensive equipment. The final choice of assay system will depend on the cost, speed, and accuracy requirements of the clinical laboratory.
Optimal use of the cytocentrifuge for recovery and diagnosis of Pneumocystis carinii in bronchoalveolar lavage and sputum specimens
Authors: Gill V J , Nelson N A , Stock F , Evans G
Published: January 2020

To facilitate the diagnosis of Pneumocystis carinii from bronchoalveolar lavage and sputum specimens, we have defined conditions for optimal use of the cytocentrifuge for this purpose. Centrifugation in the cytocentrifuge at 1,200 rpm for 10 min yielded the best recovery of P. carinii. To reliably ensure complete absorption of the fluid specimen from the cytocentrifuge chamber, it was necessary to use two absorption filters simultaneously. Different methods of treating induced sputum with mucolytic agents to process sputum with the cytocentrifuge were tried. Results of these studies and our current method for treating sputa are discussed. Comparisons of slides prepared by traditional centrifugation and by cytocentrifuge processing showed the latter to be equally effective for detecting P. carinii. The most prominent advantage of the cytocentrifuge was the much smaller area to review and consequently the shortened time required to read the slides.
Incidence and persistence of Pseudomonas aeruginosa in whirlpools
Authors: Price D , Ahearn D G
Published: January 2020

Pseudomonas aeruginosa was isolated from seven commercial and two residential whirlpools that were treated with halogens. None of the commercial whirlpools was constantly maintained at appropriate disinfection levels. Superchlorination or the draining, cleaning, disinfection, and refilling of whirlpools markedly reduced densities of P. aeruginosa in whirlpool water, but the bacterial populations were rapidly reestablished (less than 10(3) cells per ml) when disinfectant concentrations decreased below recommended levels (chlorine, 3.0 ppm [3.0 micrograms/ml]; bromine, 6.0 ppm). P. aeruginosa in the water was replenished from various sources, such as hoses used to fill the whirlpool and the biofilm in the filter and piping of the whirlpool systems. Daily monitoring and adjustment of chemical characteristics (regardless of bather load) were essential for controlling densities of P. aeruginosa.
Restriction fragment length polymorphisms of the DNA of selected Naegleria and Acanthamoeba amebae
Authors: McLaughlin G L , Brandt F H , Visvesvara G S
Published: January 2020

Fourteen strains of Naegleria fowleri, two strains of N. gruberi, and one strain each of N. australiensis, N. jadini, N. lovaniensis, Acanthamoeba sp., A. castellanii, A. polyphaga, and A. comandoni isolated from patients, soil, or water were characterized by restriction fragment length polymorphisms. Total cellular DNA (1 microgram) was digested with either HindIII, BglII, or EcoRI; separated on agarose gels; and stained with ethidium bromide. From 2 to 15 unusually prominent repetitive restriction fragment bands, totaling 15 to 50 kilobases in length and constituting probably more than 30% of the total DNA, were detected for all ameba strains. Each species displayed a characteristic pattern of repetitive restriction fragments. Digests of the four Acanthamoeba spp. displayed fewer, less intensely staining repetitive fragments than those of the Naegleria spp. All N. fowleri strains, whether isolated from the cerebrospinal fluid of patients from different parts of the world or from hot springs, had repetitive restriction fragment bands of similar total lengths (ca. 45 kilobases), and most repetitive bands displayed identical mobilities. However, polymorphic bands were useful in identifying particular isolates. Restriction fragment length polymorphism analysis generally was consistent with taxonomy based on studies of infectivity, morphology, isoenzyme patterns, and antibody reactivity and suggests that this technique may help classify amebae isolated from clinical specimens or from the environment.
Enzyme immunoassay for detection of Giardia lamblia cyst antigens in formalin-fixed and unfixed human stool
Authors: Stibbs H H , Samadpour M , Manning J F
Published: January 2020

An antigen-capture enzyme-linked immunosorbent assay employing rabbit and mouse antisera to Giardia lamblia cyst antigens was developed for the diagnosis of Giardia infection through detection of G. lamblia-specific stool antigens in cell-free aqueous eluates of human stool. This is the first report of the use of anti-cyst antibodies in an enzyme immunoassay for G. lamblia. The assay gave a positive result with 54 of 59 stools from patients with symptomatic, clinically diagnosed giardiasis, giving the test a sensitivity of 91.5%. A negative reading was obtained with all of 25 stools from G. lamblia-negative control patients. The assay could detect as few as 20 sonicated cysts added to control stool eluate. The assay was more sensitive to cyst-derived antigens than to trophozoite-derived antigens. With two exceptions, the assay gave a negative result with stools from patients infected with Entamoeba histolytica (seven), Cryptosporidium sp. (four), or Blastocystis hominis (seven) and thus appears to be specific for G. lamblia antigens. Storage of stool eluates for more than 6 months at 4 degrees C as unpreserved aqueous eluates or as formalinized eluates did not affect the ability of the assay to detect the giardial antigens. The enzyme-linked immunosorbent assay proved useful for monitoring the levels of G. lamblia-specific stool antigens in the stool of patients undergoing antigiardial chemotherapy.
Enantioselective measurement of fungal D-arabinitol in the sera of normal adults and patients with candidiasis
Authors: Wong B , Brauer K L
Published: January 2020

A new method was used to measure D-arabinitol enantioselectively in the sera of 27 healthy adults and four patients with candidiasis. Arabinitol was measured by gas chromatography in serum that was treated with and without the Klebsiella pneumoniae enzyme D-arabinitol dehydrogenase, lactic dehydrogenase, NAD, and sodium pyruvate. Since enzyme treatment removed 98% of 0 to 20 micrograms of D-arabinitol per ml and none of 0 to 20 micrograms of L-arabinitol per ml from spiked sera, D-arabinitol could be determined from the difference in the treated and untreated samples. The concentrations of D- and L-arabinitol in serum from normal subjects were 0.22 +/- 0.052 and 0.16 +/- 0.055 micrograms/ml, respectively, and their D-arabinitol/creatinine and L-arabinitol/creatinine ratios were 0.024 +/- 0.0089 and 0.017 +/- 0.0053 (all means +/- standard deviations). The infected patients all had markedly elevated serum D-arabinitol levels, but their L-arabinitol levels were either normal or proportionately much lower. The excess arabinitol in the sera of individuals with candidiasis is D-arabinitol, and use of enantioselective analytical methods should result in improved ability to diagnose and estimate the severity of candidiasis.
Plasmids in Vibrio salmonicida isolated from salmonids with hemorrhagic syndrome (Hitra disease)
Authors: Søorum H , Poppe T T , Olsvik O
Published: January 2020

Vibrio-like isolates from Atlantic salmon (Salmo salar Linnaeas) and a few from rainbow trout (S. gairdneri Richardson) suffering from hemorrhagic syndrome (Hitra disease), also called cold-water vibriosis, a disease of great importance in Norwegian fish farming, were examined for plasmid content. Of 84 strains isolated from 1982 to 1984, 70 (83.3%) had a common 21-megadalton (MDa) plasmid. A 3.4-MDa plasmid was found in 58 of the strains with the 21-MDa plasmid, and a 2.8-MDa plasmid was found in 23 of the strains with both the 21- and 3.4-MDa plasmids. The strains were isolated from fish farms along the western and northern coasts of Norway. Ten (11.9%) of the strains possessed a 61-MDa plasmid in addition to a 21-MDa plasmid. Two strains had only a 21-MDa plasmid. Of the 84-Vibrio-like isolates, 14 did not harbor plasmids identical in mass to any other plasmids found in this material. Vibrio salmonicida strains, 257 in all, isolated from salmonids with the same disease from the same area from July 1986 to July 1987, all possessed a 21-MDa plasmid, either alone or in addition to a 3.4-MDa plasmid, or a combination of 3.4- and 2.8-MDa plasmids. Six of the strains had a 5.5-MDa plasmid instead of the 3.4-MDa plasmid. The restriction endonuclease patterns of the plasmids of similar molecular mass reflected similar nucleotide sequences. The plasmid content detected in isolates of V. salmonicida obtained from a coastline of more than 2,000 km and over a period of almost 6 years is stable.
Monoclonal antibodies selectively directed against the cell wall surface of Mycobacterium tuberculosis
Authors: Mauch H , Brehmer W , Sonneborn H H , Horn J , Wagner S
Published: January 2020

In the last few years several monoclonal antibodies against Mycobacterium tuberculosis have been described, but their use as diagnostic tools has been limited. In this study we describe eight monoclonal antibodies against M. tuberculosis for diagnostic purposes. The monoclonal antibodies were selected after enzyme-linked immunosorbent assay screening with whole bacterial suspensions of mycobacteria and other bacterial species. Four monoclonal antibodies (BS100, BS101, BS102, and BS104) reacted with a whole bacterial suspension of M. tuberculosis but not with the other mycobacteria. When tested with a cytoplasmic fraction of mycobacteria the same monoclonal antibodies showed a broad cross-reactivity. Therefore the monoclonal antibodies showed not specific but selective binding to M. tuberculosis. The molecular size of the recognized antigens ranged from 12 to 71 kilodaltons as determined by the immunoblotting technique. The ability to differentiate M. tuberculosis from mycobacteria other than tuberculosis was investigated by enzyme-linked immunosorbent assay with 131 freshly cultured strains of M. tuberculosis from patients and 36 strains of mycobacteria other than tuberculosis. The monoclonal antibody BS104 could clearly distinguish between M. tuberculosis and other mycobacterial species.
DNA hybridization for assessment of response of Plasmodium falciparum to chloroquine therapy
Authors: McLaughlin G L , Deloron P , Huong A Y , Sezibera C , Campbell G H
Published: January 2020

We studied the accuracy of PFR1-AP, a synthetic DNA hybridization probe conjugated to alkaline phosphatase, in monitoring Plasmodium falciparum parasitemia during in vivo drug susceptibility surveys. Duplicate blood samples were collected from six children enrolled in a 14-day in vivo chloroquine study in Rwanda. Results obtained by microscopic examination of Giemsa-stained thick blood smears and by DNA hybridization were compared. Both techniques successfully monitored an infection with chloroquine-susceptible parasites and infections exhibiting various levels of resistance to treatment. For each patient, temporal evolution of the microscopic parasite counts and the DNA hybridization signals were closely parallel, although a wide range of rapidly changing levels of parasitemia occurred through the course of the study. This suggests that DNA hybridization assay using PFR1-AP detects P. falciparum parasites sensitively and specifically and is a valuable tool for drug resistance surveys.
Enterococcus hirae implicated as a cause of diarrhea in suckling rats
Authors: Etheridge M E , Yolken R H , Vonderfecht S L
Published: January 2020

A Lancefield group D enteric streptococcus was isolated from diarrheic suckling rats that had been inoculated orally with stool from a diarrheic human. After oral administration of the organism to other suckling rats, diarrhea was reproduced, and the enteric streptococcus was reisolated. The brush border of small intestinal villi in affected animals was coated with numerous adherent gram-positive cocci. The organism was identified as Enterococcus hirae by a battery of biochemical tests. These and previous studies indicate that certain enterococci should be considered as etiologic agents of diarrheal disease in neonatal animals.
Subdivision of O serotypes of Pseudomonas aeruginosa with monoclonal antibodies
Authors: Vale T A , Gaston M A , Pitt T L
Published: January 2020

Sixteen murine monoclonal antibodies (MAbs) against serotypes O2, O5, and O16 (serogroup II) and subtypes O2b and O5d of Pseudomonas aeruginosa were evaluated by agglutination and enzyme-linked immunosorbent assay. Six MAbs that exhibited different specificities were compared with absorbed rabbit O-type antisera for the serotyping of 55 clinical isolates of serogroup II. There was good agreement between the antibodies for strains of serotypes O2 and O2b, but MAbs revealed reproducible differences between strains that were indistinguishable with rabbit antisera. The greater serotype specificity of MAbs was illustrated by the fact that only 5 of 20 strains which were agglutinated by rabbit antiserum O16 reacted with the MAb to that serotype. One antibody, M89, that reacted with 27 of 55 serogroup II strains, apparently bound to core lipopolysaccharide epitopes. Three MAbs to the frequent serotype O6 identified six subtypes, one of which accounted for over half of the clinical strains, while two subtypes were represented by single strains only. Overall, MAbs provided a greater discrimination between strains of P. aeruginosa of the same serotype than did absorbed polyclonal antisera.
Sensitive immune dot blot test for diagnosis of Chlamydia trachomatis infection
Authors: Mearns G , Richmond S J , Storey C C
Published: January 2020

The sensitivity and specificity of an immune dot blot test (IDBT), which relies on a 125I-labeled genus-specific monoclonal antibody to detect the Chlamydia lipopolysaccharide (LPS) antigen, were improved by pretreatment of specimens with proteinase K. This enzyme destroys protein A and therefore eliminates false-positive reactions caused by the presence of Staphylococcus aureus. Proteinase K treatment also improved the ability of the assay to detect the Chlamydia LPS antigen. When the improved IDBT was compared with culture for detection of C. trachomatis in 1,394 urogenital specimens obtained from a genitourinary medicine clinic, the overall sensitivity was 96%, and LPS antigen was detected in 76 of 83 (92%) specimens that yielded less than 10 inclusions in culture. The specificity and positive and negative predictive values of the test were 97, 81.5, and 99%, respectively. Of 123 conjunctival swabs, 7 were positive by both tests and 4 swabs were positive only by IDBT. This improved IDBT provides a simple, reliable alternative to culture for the detection of C. trachomatis in urogenital and conjunctival specimens.
Effects of transport temperature and medium on recovery of Bordetella pertussis from nasopharyngeal swabs
Authors: Morrill W E , Barbaree J M , Fields B S , Sanden G N , Martin W T
Published: January 2020

We compared relative recoveries of Bordetella pertussis from simulated nasopharyngeal (NP) specimens incubated in three separate transport media at different temperatures. Transport media included one-half-strength Regan-Lowe (RL.5), Regan-Lowe with one-half-strength agar (RL.5A), and buffered charcoal-yeast extract agar supplemented with alpha-ketoglutarate, lincomycin, and anisomycin (BCYE alpha LA). For each transport medium, recovery of B. pertussis was least efficient after storage at 25 degrees C. The highest recovery of B. pertussis from a mixed culture was achieved with RL.5 at 4 degrees C. Overall, RL.5 and RL.5A were comparable as transport media whether held at 4 or 25 degrees C, but fewer organisms were recovered from BCYE alpha LA. In addition, Regan-Lowe (RL), Bordet-Gengou, and cyclodextrin media were compared as primary isolation media for recovering B. pertussis from simulated NP swabs held at 4 and 35 degrees C in RL.5 medium. The highest recovery of B. pertussis was obtained on RL primary isolation medium. Bordet-Gengou medium recovered only 80% and cyclodextrin medium recovered less than 60% of the numbers recovered on RL medium. Based on these results, refrigeration (4 degrees C) of NP swabs shipped in RL.5 transport medium and using RL as the primary isolation medium are recommended for recovering B. pertussis from swab specimens.
Detection with monoclonal antibody of Salmonella typhi antigen 9 in specimens from patients
Authors: Chaicumpa W , Thin-Inta W , Khusmith S , Tapchaisri P , Echeverria P , Kalambaheti T , Chongsa-Nguan M
Published: January 2020

Monoclonal antibodies were raised against Barber antigen (Ba) of Salmonella typhi 0901. Antibodies produced to antigen 9 of group D salmonellae were used in double- and triple-sandwich antibody enzyme-linked immunosorbent assays (ELISAs) for detecting antigen 9 in urine and plasma specimens from three groups of patients and 49 controls. The triple-antibody ELISA detected the antigen in urine samples from 11 of 18 (65%) patients with hemoculture-proven typhoid (group 1) and 12 of 39 (31%) patients with clinical features compatible with typhoid but whose hemocultures were negative (group 2). This ELISA was negative in three patients from whom Salmonella paratyphi A, Escherichia coli, and Klebsiella pneumoniae (group 3) were isolated by hemoculture and in all healthy controls. The double-antibody sandwich ELISA was positive in 41 and 15% of urine samples from patients in groups 1 and 2, respectively, and was negative with samples from two patients from group 3 and all controls. The sensitivity and specificity compared with those for healthy controls were 65 and 100%, respectively, for the triple-antibody ELISA. Although as little as 7.8 ng of homologous lipopolysaccharide could be detected, background in clinical specimens prevented accurate interpretation of the detection of this antigen in serum. Results were best with urine specimens.