bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of a 17-kilodalton Fasciola hepatica immunodiagnostic antigen by the enzyme-linked immunoelectrotransfer blot technique
Authors: Hillyer G V , Soler de Galanes M
Published: January 2020

Sera obtained from human patients, calves, sheep, and rabbits infected with Fasciola hepatica were tested by the Falcon assay screening test enzyme-linked immunosorbent assay (FAST-ELISA) and the enzyme-linked immunoelectrotransfer blot (EITB) techniques with Fasciola hepatica excretory-secretory antigens in order to evaluate their immunodiagnostic potential. The study included sera from 13 patients infected with F. hepatica or a history suggesting fascioliasis, 5 patients infected and treated with bithionol or praziquantel (3 were cured with bithionol), 10 patients infected with Schistosoma mansoni, 6 infected with Trichinella spiralis, and 13 controls and sera from calves, sheep, and rabbits with a primary F. hepatica infection. By FAST-ELISA with F. hepatica excretory-secretory antigens, the serum samples from fascioliasis patients gave the highest absorbance values, and the schistosomiasis patient sera gave intermediate values compared with a normal human serum control. Also by FAST-ELISA, the values for serum from patients with fascioliasis decreased steadily after cure, reaching normal levels 20 to 47 weeks postcure. In contrast, the serum from two patients who had been treated but were not yet cured had high levels of antibodies for up to 3 years of infection. By EITB, the serum samples from humans, rabbits, cattle, and sheep with fascioliasis recognized two antigenic polypeptides of 17 and 63 kilodaltons (kDa) in the form of sharp bands. For humans, this recognition lasted for at least 3 years of infection. Sera from individuals with schistosomiasis mansoni or trichinosis or from normal controls did not recognize the 17-kDa F. hepatica antigenic polypeptide. However, serum from one human with S. mansoni and one with T. spiralis infection has slight bands in the 63-kDa region, suggesting cross-reactivity. Reactivity to the 17-kDa polypeptide was absent in fascioliasis patients at 1 year postcure. Reactivity to the 63-kDa polypeptide was significantly diminished in fascioliasis patients at 1 year postcure. The sera from rabbits with a primary F. hepatica infection also recognized both the 17- and 63-kDa antigenic polypeptides by week 4 of infection. Reactivity to both antigens diminished significantly 6 weeks postcure and disappeared by 8 weeks postcure. The sera from infected cattle and sheep recognized these two antigenic polypeptides by week 8 of infection. These studies suggest that the 17-kDa F. hepatica excretory secretory antigen is an excellent candidate for the immunodiagnosis of acute and chronic fascioliasis. Purification of this antigen and its application to quantitative serologic tests will permit further analysis of its predictive value to evaluate cure.
Comparison of the Quantum II, API Yeast Ident, and AutoMicrobic systems for identification of clinical yeast isolates
Authors: Pfaller M A , Preston T , Bale M , Koontz F P , Body B A
Published: January 2020

The Quantum II Yeast Identification System (Abbott Laboratories) is a microprocessor-based spectrophotometric system for identification of clinical yeast isolates within 24 h. We compared the Quantum II system with the API Yeast Ident (Analytab Products) and the AutoMicrobic System Yeast Biochemical Card (AMS-YBC; Vitek Systems, Inc.) for the identification of 221 clinical yeast isolates, including 120 common clinical isolates (Candida albicans, C. tropicalis, C. parapsilosis, Torulopsis glabrata, and Cryptococcus neoformans) and 101 relatively uncommon clinical isolates. The API 20C (Analytab) was used as the reference system. The Quantum II and AMS-YBC systems correctly identified 181 (82%) and 184 (83%) isolates, respectively, whereas the Yeast Ident system correctly identified 132 (60%) isolates. Of the 120 common clinical isolates, 113 (94%) were correctly identified by Quantum II, 103 (86%) were correctly identified by AMS-YBC, and 83 (69%) were correctly identified by Yeast Ident. Of the 101 uncommon clinical isolates tested, 68 (67%) were correctly identified by Quantum II, 81 (80%) were correctly identified by AMS-YBC, and 49 (49%) were correctly identified by Yeast Ident. The overall accuracy of the Quantum II, AMS-YBC, and API Yeast Ident was not sufficient to recommend any of these systems for routine use in the clinical microbiology laboratory without substantial expansion of the respective data bases.
Vancomycin-resistant gram-positive bacteria isolated from human sources
Authors: Ruoff K L , Kuritzkes D R , Wolfson J S , Ferraro M J
Published: January 2020

Recent reports of infections with vancomycin-resistant gram-positive bacteria prompted us to study vancomycin-resistant isolates from human sources to characterize the types of bacteria displaying this phenotype. Thirty-six vancomycin-resistant gram-positive isolates, 14 from clinical specimens and 22 from stool samples, were identified. These isolates were tentatively identified as Lactobacillus spp. (25 strains), Leuconostoc spp. (6 strains), and Pediococcus spp. (3 strains) on the basis of morphology and physiological tests. Two isolates of indeterminate morphology could not be unambiguously assigned to a genus. Four isolates of vancomycin-resistant lactobacilli from normally sterile body sites were considered to be clinically significant. Vancomycin-resistant gram-positive bacteria may represent an emerging class of nosocomial pathogens. Better methods for distinguishing the various genera in the clinical microbiology laboratory are needed.
Monoclonal antibody-based sandwich enzyme-linked immunosorbent assay for detection of Bordetella pertussis filamentous hemagglutinin
Authors: Gustafsson B , Askelöf P
Published: January 2020

Hybrid cell lines producing monoclonal antibodies against Bordetella pertussis filamentous hemagglutinin (FHA) were established. The specificity of the antibodies was ascertained by enzyme-linked immunosorbent assay (ELISA), sandwich ELISA, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by electroblotting. The monoclonal antibody-based sandwich ELISA was developed for detection of B. pertussis FHA. The assay had a detection limit of B. pertussis FHA in concentrations ranging from 7 to 15 ng/ml. The assay was also able to detect whole B. pertussis, Bordetella parapertussis, and Bordetella bronchiseptica bacteria. No cross-reactions were observed with strains of Branhamella catarrhalis, Neisseria meningitidis, Haemophilus influenzae, Klebsiella pneumoniae, Legionella pneumophila, Streptococcus miteor, or Streptococcus pneumoniae. The monoclonal antibodies might be useful for the detection of soluble antigens and whole bacteria in clinical samples and for studies of the immunochemical structure of B. pertussis FHA.
Comparative evaluation of selective media for isolation of Pseudomonas cepacia from cystic fibrosis patients and environmental sources
Authors: Carson L A , Tablan O C , Cusick L B , Jarvis W R , Favero M S , Bland L A
Published: January 2020

Pseudomonas cepacia has recently emerged as an important pathogen affecting cystic fibrosis (CF) patients. We evaluated three selective media to assess their comparative potential for identification of patients colonized with P. cepacia and for efficacy of detection of P. cepacia in environmental fluids. Test organisms included P. cepacia isolates from CF patients (10 each from two CF centers), non-CF patients (10 isolates), and environmental sources (10 isolates). Microbiologic assays were done by the membrane filter procedure; filters were placed on P. cepacia medium (PCM), OFPBL, TB-T, MacConkey agar (MAC), and blood agar (BA) or Standard Methods (SM) sugar, and colonies were counted after incubation at 30 or 35 degrees C for 72 h. Mean recovery efficiencies (MREs) (mean CFU/ml on selective media compared with CFU/ml on BA controls) for environmental and non-CF P. cepacia and patient isolates from one CF center showed a rank order of PCM greater than OFPBL greater than TB-T; for isolates from a second CF center, a rank order of PCM greater than TB-T greater than OFPBL was obtained. MREs for CF center isolates were generally lower than for non-CF patients or environmental isolates on P. cepacia-selective media. With MAC, the MREs for each group of CF isolates were extremely low (14 and 2%) compared with those for non-CF patient (47%) or environmental (84%) isolates. In laboratory and field studies, PCM and OFPBL showed good selectivity against bacteria commonly associated with CF patient respiratory secretions. These findings show that selective media should be used in clinical settings where P. cepacia is sought. With environmental fluids from CF centers, P. cepacia-selective media showed low selectivity against a variety of gram-negative water bacteria and appeared to afford little advantage over SM agar for isolating P. cepacia from environmental samples.
Immunoglobulin A antibodies to Trypanosoma cruzi antigens in digestive forms of Chagas' disease
Authors: Primavera K S , Hoshino-Shimizu S , Umezawa E S , Peres B A , Manigot D A , Camargo M E
Published: January 2020

In an attempt to find a serological marker for the diagnosis of chronic digestive forms of Chagas' disease, we compared amastigote and trypomastigote antigens obtained from immunosuppressed mice infected with Trypanosoma cruzi (Y strain) with conventional epimastigote antigens to search for immunoglobulin A (IgA) antibodies. A total of 255 serum samples from patients with acute and chronic (indeterminate, digestive, and cardiac) forms of Chagas' disease and with nonchagasic diseases and from healthy individuals were studied. Amastigote antigens proved to be the most adequate for our purpose, since IgA antibodies could be detected in 23 of 25 serum samples from patients with digestive forms, with relative indices of sensitivity, specificity, and efficiency of 0.920, 0.911, and 0.912, respectively. These antigens also showed high reactivity with IgA antibodies, with a geometric mean titer of 16,635 (12.7 log2). IgA antibodies were detected in 16 of 28 serum samples from patients with the acute form as well, but this clinical form is easily distinguished from the chronic form by the demonstration of IgM antibodies. Poor results were seen with trypomastigote and epimastigote antigens. The finding of IgA antibodies in about 20% of indeterminate forms and 20% of cardiac forms, although in low titers, requires further investigation to ascertain their role as an early signal of gastrointestinal lesions. In addition, the amastigote antigens described here seem more convenient for use in endemic areas than those obtained from cell cultures because of their lower cost.
Evaluation of the KOH test and the antibiotic disk test in routine clinical anaerobic bacteriology
Authors: Bourgault A M , Lamothe F
Published: January 2020

We have evaluated the KOH test, the antibiotic disk identification test, and the Gram stain reaction for the preliminary grouping of gram-positive and gram-negative anaerobes and have assessed the value of erythromycin 60-micrograms-disk resistance as a predictive index of clindamycin resistance among anaerobes. By testing 931 clinical isolates, 281 gram positive and 650 gram negative, with the KOH test and vancomycin 5-micrograms-disk test, we obtained the following parameters: sensitivity, 89.7 and 97.1%; specificity, 97.5 and 98.3%; positive predictive value, 80.4 and 98.7%; and efficiency, 92.1 and 98% for the KOH test and the vancomycin test, respectively. The KOH reaction incorrectly grouped 42 of 97 Bacteroides bivius and 12 of 50 pigmented Bacteroides strains. The vancomycin test correctly identified 63 of 67 gram-negative strains that had given a negative KOH reaction. The erythromycin disk result correctly predicted clindamycin resistance in gram-negative isolates but had a sensitivity of 85.7%, a specificity of 92.4%, and a positive predictive value of 42.8% for gram-positive isolates. Therefore, the use of these preliminary identification tests can assist in the correct grouping of anaerobes and accurately predict significant clindamycin resistance in gram-negative anaerobic bacteria.
Possible common biological and immunological properties for detecting encapsulated strains of Staphylococcus epidermidis
Authors: Yamada T , Ichiman Y , Yoshida K
Published: January 2020

Twenty strains of capsular type II Staphylococcus epidermidis, determined by the method of Ichiman, were obtained from clinical specimens. Among them, 5, 5, and 10 strains were 4+, 3+, and 2+ in the intensities of their reactions against fluorescent antibody, respectively. Strains exhibiting 4+ and 3+ intensities were mouse virulent and phage nontypable, while 2+ strains were mouse avirulent and phage typable. When three strains randomly selected from each of the mouse-virulent and mouse-avirulent strains were compared in terms of their cell volume indices, all mouse-virulent strains had significantly higher indices (average, 1.86 times) than the mouse-avirulent strains. With intraperitoneal injection of the strains into mice, strains with higher cell volume indices resisted ingestion by peritoneal cells, while strains with low cell volume indices were sensitive to phagocytosis. When the capacity to absorb a definite amount of passive protective activity in rabbit antiserum prepared with capsular type II strains was compared among these strains, 10 to 20 mg of mouse-virulent strains was capable of completely absorbing the passive protective activity, whereas more than 80 mg of the cells was required for similar absorption by mouse-avirulent strains. In ultra-thin sections of three mouse-virulent strains stained with ferritin-conjugated rabbit antiserum, well-defined capsules were detected around cell walls; however, no capsule was seen around the walls of three mouse-avirulent strains.
Lack of Shiga-like cytotoxin production by enteroinvasive Escherichia coli
Authors: Cleary T G , Murray B E
Published: January 2020

Enteroinvasive Escherichia coli has not been extensively studied for cytotoxin production. We evaluated 30 well-characterized enteroinvasive E. coli strains of all the known invasive serogroups from several geographic regions for their ability to produce Shiga-like cytotoxic activity assayed in a HeLa cell system. None of these strains produced cytotoxic activity that was neutralizable with antibody to Shiga-like toxin I or II.
Four cases of vesicular lesions in adults caused by enterovirus infections
Authors: Dechamps C , Peigue-Lafeuille H H , Laveran H , Beytout J , Roger H , Beytout D
Published: January 2020

Echovirus types 4 and 33 and coxsackievirus type B1 were recovered from vesicular lesions in four adults. Patient 1 had cutaneous localized vesicles, patient 2 had a recurrent cutaneous vesicle, and patients 3 and 4 had mucosal vesicles. Three of the patients were suspected of having herpesvirus lesions. One of the patients was a human immunodeficiency virus type 1-seropositive man, and the enterovirus infection was the first clinical manifestation. Our results underline the importance of virological diagnosis before treatment with acyclovir, especially for immunocompromised patients.
Genetic confirmation of identities of neurotoxigenic Clostridium baratii and Clostridium butyricum implicated as agents of infant botulism
Authors: Suen J C , Hatheway C L , Steigerwalt A G , Brenner D J
Published: January 2020

Two unusual neurotoxigenic clostridia isolated from fecal specimens from patients with type F and type E infant botulism were phenotypically identical to the existing species Clostridium baratii and C. butyricum, respectively. DNA hybridization experiments confirmed that one strain was C. baratii and that the other was C. butyricum. These species therefore do contain neurotoxigenic strains and are possible causes of infant botulism.
Characterization of a circular plasmid from Borrelia burgdorferi, etiologic agent of Lyme disease
Authors: Hyde F W , Johnson R C
Published: January 2020

Borrelia burgdorferi, the etiologic agent of Lyme disease, was recently shown to contain plasmid DNA. Two plasmid species have been described in strain CT1, a Wisconsin tick isolate: a 9.2-kilobase entity; and a larger, 70-kilobase entity. Characterization of the 9.2-kilobase entity by using DNase I and restriction endonucleases demonstrated that the plasmid is supercoiled and exists as a stable dimer in this strain. The role played by the plasmid in B. burgdorferi is unknown.
New Borrelia burgdorferi antigenic variant isolated from Ixodes dammini from upstate New York
Authors: Anderson J F , Magnarelli L A , McAninch J B
Published: January 2020

A previously undescribed Borrelia burgdorferi antigenic variant was isolated from each of four Ixodes dammini larvae removed from white-footed mice, Peromyscus leucopus, captured in Millbrook, N.Y. This site is in the northern range of the known distribution of the tick in the northeastern United States. The molecular weights of approximately 32,500 and 35,500 for outer surface A and outer surface B proteins, respectively, were distinctly higher than those for previously characterized isolates from North American ticks, humans, and wild mammals. A prominent low-molecular-weight protein of about 23,500 was also present. All four isolates infected Syrian hamsters and retained their antigenicity after passage through these rodent hosts. Serum samples from patients with Lyme disease tended to have immunoglobulin M, immunoglobulin G, and immunoglobulin antibodies to Connecticut B. burgdorferi 2591 at titers slightly higher than or equal to those recorded for an antigenically different strain of B. burgdorferi from Millbrook, N.Y.
Cavitating pneumonia caused by Corynebacterium group JK
Authors: McNaughton R D , Villanueva R R , Donnelly R , Freedman J , Nawrot R
Published: January 2020

Corynebacterium group JK organisms were isolated from lung fluid aspirated with a fine needle from one of four thick-walled cavitary lesions in a 72-year-old female. Cultures and stains for mycobacteria and fungi were negative. The patient was successfully treated with an 8-week course of vancomycin.
Inadequate mixing in microdilution wells during preparation of antimicrobial dilutions for susceptibility testing
Authors: Zhi J G , Nightingale C H , Quintiliani R
Published: January 2020

An equation representing a twofold series of antibiotic dilutions was derived. The theoretical results were then validated with experimental observations of piperacillin against Pseudomonas aeruginosa. Insufficient mixing leads to an erroneously low MIC. It is concluded that maintaining antibiotic concentration equilibrium during microdilution is required for accurate microdilution susceptibility tests.
Addition of monoclonal antibodies specific for Rickettsia akari to the rickettsial diagnostic panel
Authors: McDade J E , Black C M , Roumillat L F , Redus M A , Spruill C L
Published: January 2020

Monoclonal antibodies were produced from mice infected with Rickettsia akari (the etiologic agent of rickettsialpox) and evaluated for specificity in indirect fluorescent-antibody tests with 23 different rickettsial antigens. Of the nine antibodies that were evaluated, two were specific for R. akari and four reacted with R. akari and all other spotted fever group rickettsiae. The remaining three antibodies reacted with some, but not all, members of the spotted fever group. None of the antibodies reacted with typhus, scrub typhus, trench fever, or Q fever rickettsiae. Adding these antibodies to the list of available diagnostic reagents will facilitate identification of rickettsial diseases, particularly those caused by members of the spotted fever group, where the clinical presentations are similar and the etiologic agents are closely related antigenically.
Disseminated infection caused by urease-negative Cryptococcus neoformans
Authors: Ruane P J , Walker L J , George W L
Published: January 2020

We report a case of fungemia and disseminated disease caused by a urease-negative strain of Cryptococcus neoformans in a patient with the acquired immune deficiency syndrome. Except for failure to hydrolyze urea, the microbiological characteristics of the isolate were typical of C. neoformans. Laboratory specialists should be aware of the occurrence of atypical strains of C. neoformans, particularly those recovered from patients with the acquired immune deficiency syndrome.
Improved detection of heat-labile enterotoxin of enterotoxigenic Escherichia coli by using a commercial coagglutination test
Authors: Rudensky B , Isacsohn M , Zilberberg A
Published: January 2020

Escherichia coli strains grown on lincomycin-supplemented Mundell agar and on blood agar were compared for their ability to produce heat-labile enterotoxin, as detected by a commercial coagglutination kit. The special agar allowed more strains to be detected, and the results were much more clear-cut.
Characterization of a soluble protein of Coccidiodes immitis with activity as an immunodiffusion-complement fixation antigen
Authors: Zimmer B L , Pappagianis D
Published: January 2020

A 48-kilodalton (kDa) electrophoretically distinct antigen from Coccidioides immitis mycelial- and spherule-endospore-phase filtrates was previously associated by immunoblotting with the immunodiffusion band that corresponds to complement-fixing activity (ID-CF). To characterize this antigen and its precursor, both mycelial- and spherule-endospore-phase filtrates were fractionated by size exclusion chromatography, lectin affinity chromatography, and nondenaturing electrophoresis. By size exclusion chromatography, most of the protein and carbohydrate of the crude filtrates eluted in a peak of average molecular size less than 30 kDa, although other components were detected. ID-CF activity was associated with the component at a relative mobility of 110 kDa. Fractions containing the ID band that corresponded to tube precipitin activity occurred from 200 to 40 kDa. The appearance of the 48-kDa band in denaturing sodium dodecyl sulfate-polyacrylamide gel electrophoresis (PAGE) specifically coincided with the fractions containing ID-CF activity. Nondenaturing PAGE of filtrates showed silver-stainable and immunoblot-reactive bands in the region of 110 kDa. Prior treatment with pronase destroyed this electrophoretically separable antigen, whereas periodate had no effect. Trypsin did not affect the 110-kDa band in unheated or unreduced antigen. Mycelial filtrates were chromatographed on lentil lectin or concanavalin A-Sepharose 4B to deplete them of glucose- or mannose-containing carbohydrate. The effluent fraction contained ID-CF activity and, upon denaturing electrophoresis, the 48-kDa antigen. The 110-kDa protein represents the ID-CF antigen which is heat labile and denatured to a 48-kDa band by sodium dodecyl sulfate-PAGE.
Rapid detection of positive blood cultures with the BACTEC NR-660 does not require first-day subculturing
Authors: Levi M H , Gialanella P , Motyl M R , McKitrick J C
Published: January 2020

An analysis of blood culture data was performed to determine whether subculturing within the first 24 h of incubation decreased the time to detection of positive blood cultures when compared with the routine use of the BACTEC NR-660 system (Johnston Laboratories, Inc., Towson, Md.). During a 9-month period (June 1985 to February 1986), 17,913 blood cultures were received in our laboratory, of which 1,463 (8.2%) became positive. Of the positive cultures, 97% were detected with equal or greater rapidity by the NR-660 system than by visual inspection and first-day blind subculturing. There were 37 delayed positive cultures from which only one isolate (0.07%) was not eventually detected by the NR-660 system. Coagulase-negative staphylococcus was the most frequent isolate among the delayed positive cultures, but only 3 of 15 isolates were known to be clinically significant isolates. The longest delay in detection by the NR-660 system was 6 days for one isolate of Cryptococcus neoformans and one isolate of Klebsiella pneumoniae. Although subculturing may decrease the time to detection of a few cultures, the majority of positive blood cultures were detected faster or with equal speed by the NR-660 system. When the data were evaluated, routine use of the NR-660 system was sufficient for the detection of positive blood cultures and was cost-effective.
Rapid method for differentiation of Trichophyton rubrum, Trichophyton mentagrophytes, and related dermatophyte species
Authors: Summerbell R C , Rosenthal S A , Kane J
Published: January 2020

Bromocresol purple-milk solids-glucose medium, proposed by Fischer and Kane in 1971 (Mycopathol. Mycol. Appl. 43:169-180, 1971) as an aid in the rapid determination of Trichophyton rubrum and Trichophyton mentagrophytes, was evaluated across a wide range of isolates to determine its accuracy and efficacy in the clinical laboratory. Results showed that it facilitated accurate determination of typical and atypical isolates of both species and also permitted the rapid identification of other closely related and similar species. Identification of all dermatophyte species tested was possible within 7 to 10 days. Occult contamination of isolates by antibiotic-resistant bacteria did not hinder identification.
Serologic confirmation of Neisseria gonorrhoeae by monoclonal antibody-based coagglutination procedures
Authors: Anand C M , Gubash S M , Shaw H
Published: January 2020

Two commercially available monoclonal antibody coagglutination tests, Phadebact Monoclonal GC OMNI Test (PMGOT; Pharmacia Diagnostics AB, Uppsala, Sweden) and GonoGen (GG; New Horizons Diagnostics, Columbia, Md.), for the confirmation of Neisseria gonorrhoeae were evaluated. The sensitivities of PMGOT and GG were 99.2 and 98.7% and the specificities were 91.5 and 100.0%, respectively. False-positive reactions were observed with Neisseria lactamica and Neisseria meningitidis in PMGOT. A modification of the procedure recommended by the manufacturer for PMGOT was done by substituting Todd-Hewitt broth for 0.9% saline to prepare the suspension of the test organism. This eliminated technical difficulties with the test and resulted in a sensitivity and a specificity of 99.3 and 100.0%, respectively. Advantages offered by the modified PMGOT over GG were the better predictive value of the negative test, the lower cost, the ease of reading of the test, and the lack of noninterpretable results.
Monoclonal antibodies delineate multiple epitopes on the O antigens of Salmonella typhi lipopolysaccharide
Authors: Qadri A , Gupta S K , Talwar G P
Published: January 2020

Fifteen monoclonal antibodies (MAbs) directed against Salmonella typhi were produced and characterized. The specificities of the antibodies were determined by their binding patterns in an enzyme immunoassay, with a panel of lipopolysaccharides isolated from different bacteria. Seven MAbs reacted with S. typhi, Salmonella enteritidis, and Salmonella dublin (all belonging to serogroup D). One MAb also reacted with Salmonella paratyphi A and S. paratyphi B. Five MAbs reacted with S. typhi, S. enteritidis, S. dublin, and S. paratyphi B. Two MAbs did not bind to any lipopolysaccharide but showed reactivity with bacterial sonic extracts isolated from S. typhi, S. paratyphi A, S. paratyphi B, Escherichia coli, and Shigella sonnei. These antibodies would be helpful in studying the complexity of antigenic determinants expressed by S. typhi and the nature of the antibody response during typhoid and paratyphoid fevers and also in the diagnosis of the disease.
Value of semiquantitative cultures of blood drawn through catheter hubs for estimating the risk of catheter tip colonization in cancer patients
Authors: Andremont A , Paulet R , Nitenberg G , Hill C
Published: January 2020

Colonization of central catheter tips has been associated with catheter-related infections. This colonization is defined as the presence of over 15 CFU in a semiquantitative catheter tip culture performed after catheter removal. Using a simple pour-plate technique, we determined the microbial concentrations in samples of blood collected via the hubs of 205 central catheters while they were in position in 179 cancer patients. All catheters were removed within three days of blood collection via the hub and cultured semiquantitatively. We then compared the results for the hub blood cultures and catheter tip cultures. Cultures from 18% of the hub samples and 29% of the tips were positive. When a cutoff limit of 1,000 CFU/ml was used for the blood cultures, the sensitivity was 20% and the specificity was 99% for estimating catheter tip colonization. These values did not seem to be related to the underlying disease, the site of catheter insertion, or the antibiotic treatment administered at catheter removal. We conclude that, if positive, cultures of blood sampled via the catheter hub can be useful in assessing the risk of catheter colonization in cancer patients.
Specificity of antibodies to immunodominant mycobacterial antigens in pulmonary tuberculosis
Authors: Jackett P S , Bothamley G H , Batra H V , Mistry A , Young D B , Ivanyi J
Published: January 2020

A serological survey was performed in groups of patients with active sputum smear-positive or smear-negative pulmonary tuberculosis, healthy household contacts, and controls. Sera were tested for titers of antibodies which bound to each of five purified mycobacterial antigens by enzyme immunoassay and for competition of binding to single epitopes, using six radiolabeled monoclonal antibodies directed toward corresponding molecules. The evaluation of diagnostic specificity was based on a positive score represented by titers above the cutoff point of 2 standard deviations above the mean titer of a control group. For smear-positive samples, the best sensitivity (83%) was achieved by exclusive use of the 38-kilodalton (kDa) antigen or its corresponding monoclonal antibodies. For smear-negative samples, levels of antibodies binding to the 19-kDa antigen showed a lower sensitivity of 62% compared with the control group or 38% compared with the contact group. Titers of antibody binding to the 14-kDa antigen were raised in Mycobacterium bovis BCG-vaccinated contacts, indicating that the greatest potential of this antigen may be in the detection of infection in a population for which tuberculin testing is unreliable. The results demonstrated the differing antibody responses to each of the tested antigens and distinct associations with the stage of infection or disease.
Quality control of individual components used in Middlebrook 7H10 medium for mycobacterial susceptibility testing
Authors: Guthertz L S , Griffith M E , Ford E G , Janda J M , Midura T F
Published: January 2020

The acceptability of different lots of commercial components which constitute our basal medium for susceptibility testing of mycobacteria was evaluated. The basal medium consisted of Middlebrook 7H10 agar supplemented with 10% oleic acid-albumin-dextrose-catalase and 0.5% glycerol. Studies were performed by using three separate microbiologic assays, and results were compared with parallel tests on previously standardized and acceptable lots of media. Components were rejected if comparison with standardized medium showed a major change in growth support or susceptibility status of any reference strain to any antimicrobial agent tested. Of the components tested in such a manner, 7 of 23 (30%) lots of 10% oleic acid-albumin-dextrose-catalase, 2 of 13 (15%) lots of Middlebrook 7H10 agar, and 0 of 5 lots of glycerol were found to be unacceptable. This study demonstrates that individual lots of components of this basal medium may vary significantly in their suitability for susceptibility testing, and failure to detect such variation may dramatically affect susceptibility profiles.
Monoclonal antibodies to Vibrio cholerae O1 serotype inaba
Authors: Ito T , Yokota T
Published: January 2020

Eighteen monoclonal antibodies were generated from mice immunized with Vibrio cholerae O1 serotype Inaba. Reactivities of these antibodies were investigated by slide agglutination, microdilution agglutination, and passive hemagglutination tests. Although all antibodies reacted to the Inaba-type cells, reactivity to Ogawa cells showed some variation. These antibodies were roughly subdivided into three groups by slide agglutination tests and microdilution agglutination tests by using type-specific standard strains. The first group showed almost identical reactivities to both the Ogawa- and the Inaba-type cells, while the second group reacted to Inaba-type cells but only very weakly reacted to Ogawa-type cells. The third group reacted only to Inaba-type cells; no agglutination was observed for Ogawa-type cells in either the slide agglutination or the microdilution agglutination tests. Most of the third group showed cross-reactivity to Brucella abortus and Yersinia enterocolitica O9. Results of passive hemagglutination tests showed that all 18 antibodies were to the lipopolysaccharide of V. cholerae O1.
Characteristics of anti-Legionella antibodies in patients infected with Legionella pneumophila serogroups 1, 6, and 10
Authors: van Zwet T L , Meenhorst P L , Leijh P C , Daha M R , van Furth R
Published: January 2020

Nosocomial infections with Legionella pneumophila serogroups 1 and 10 in the Leiden University Hospital and infections with L. pneumophila serogroup 6 in neighboring hospitals gave us an opportunity to study the development of opsonizing antibodies against L. pneumophila serogroups 1, 6, and 10 in the serum of 13 patients. Seven of these patients were infected with L. pneumophila serogroup 1, two were infected with serogroup 6, and four were infected with serogroup 10. The opsonic cross-reactivity of antibodies against these serogroups of L. pneumophila and complement involvement in opsonization were also investigated. Convalescent-phase sera from patients infected with L. pneumophila serogroup 1 or 6 were able to promote ingestion of these serogroups by polymorphonuclear leukocytes, whereas ingestion of L. pneumophila serogroup 10 was enhanced only in the presence of convalescent-phase sera from patients infected with this serogroup. Opsonization of L. pneumophila serogroups 1, 6, and 10 was complement dependent.
Identification of Escherichia coli serotype O157 strains by using a monoclonal antibody
Authors: Perry M B , Bundle D R , Gidney M A , Lior H
Published: January 2020

The O157 antigenic determinant of Escherichia coli serotype O157:H7, an important bacterial pathogen, resides in the polysaccharide portion of its cellular lipopolysaccharide component which, from structural studies, was identified as a linear polymer of a repeating tetrasaccharide unit composed of D-glucose, L-fucose, 2-acetamido-2-deoxy-D-galactose, and 4-acetamido-4,6-dideoxy-D-mannose residues (1:1:1:1). Hybrid cells producing monoclonal antibodies against the E. coli O157 antigen were obtained by fusion of myeloma cells with lymphocytes from BALB/c mice immunized with killed E. coli O157:117 cells. Clones were selected for binding specificity with purified O polysaccharide. One monoclonal antibody used in direct slide agglutinations or in coagglutination reactions with Staphylococcus aureus Cowan 1 cells sensitized with the affinity column-purified antibody accurately detected all strains of E. coli O157 tested. This selected monoclonal antibody did not agglutinate E. coli strains such as E. coli O7 and E. coli O116 or other bacteria which are known to give positive agglutinations with conventional polyclonal E. coli antisera. These results indicate that the monoclonal antibody is a superior specific-typing reagent.
Immunoblots, antimicrobial resistance, and bacteriophage typing of oxacillin-resistant Staphylococcus aureus
Authors: Mulligan M E , Kwok R Y , Citron D M , John J F , Smith P B
Published: January 2020

An immunoblotting system was developed for typing of oxacillin-resistant Staphylococcus aureus. Clinical isolates recovered during a 40-month period at a single institution were evaluated with this typing scheme. Results were compared with susceptibility patterns and with bacteriophage typing results for 100 clinical isolates and with plasmid fingerprints for 14 isolates. Immunoblotting was found to be a useful method with good reproducibility that distinguished seven major groups of patient isolates that were clinically and epidemiologically related. Susceptibility patterns showed specific correlations with other typing results but were inferior to immunoblotting and phage typing for differentiating major groups of organisms. Plasmid profiles failed to distinguish two major groups that were readily identified by immunoblots and phage typing. There was evidence of increasing antimicrobial resistance of endemic hospital strains. Immunoblotting correlated well with phage typing, offered an alternative method for typing isolates that could not be typed by phage typing, and was superior to susceptibility testing and plasmid profiles for distinguishing different groups of oxacillin-resistant S. aureus at our institution.
Variability of clarithromycin and erythromycin susceptibility tests with Haemophilus influenzae in four different broth media and correlation with the standard disk diffusion test
Authors: Barry A L , Fernandes P B , Jorgensen J H , Thornsberry C , Hardy D J , Jones R N
Published: January 2020

Four separate laboratories performed antimicrobial susceptibility tests with 40 Haemophilus influenzae isolates, each tested in triplicate. Erythromycin and a new macrolide, clarithromycin (A-56268; TE-031), were tested by the disk diffusion method, by the agar dilution procedure in two different media, and by broth microdilution tests in four different media. Erythromycin MICs for 90% of the strains were 16 micrograms/ml in Mueller-Hinton broth with 3% lysed horse blood and NAD, 4.0 micrograms/ml in hemophilus test medium, and 2.0 micrograms/ml in supplemented Schaedler broth or in the fastidious broth medium from Beckman Instruments, Inc. Clarithromycin MICs were generally 1 doubling dilution greater than erythromycin MICs in each of the media. Erythromycin disk tests corresponded best with MICs determined in the fastidious broth medium. In that same medium, clarithromycin MICs were about 1 doubling dilution greater than what would be expected from the results of disk tests. Because there were fewer growth failures, hemophilus test medium is recommended for microdilution tests with H. influenzae. Incubation of all tests for a full 24 h without an increased CO2 atmosphere was needed to achieve maximal precision of the tests. Interlaboratory and intralaboratory reproducibility of all tests was satisfactory.
Detection of human immunodeficiency virus antigen in vitreous humor
Authors: Cowan W T , Wahab S , Lucia H L
Published: January 2020

The vitreous humor from 11 patients with acquired immunodeficiency syndrome was obtained at postmortem examination and tested for human immunodeficiency virus antigen and antibody by using the Abbott enzyme-linked immunosorbent assay procedures. Five patients had detectable antigen, supporting the recent observation that the virus may directly infect the retina.
Outer membranes of environmental isolates of Pseudomonas aeruginosa
Authors: Hancock R E , Chan L
Published: January 2020

The outer membrane composition of 30 environmental isolates of Pseudomonas aeruginosa was examined. Other than variations in the amounts of lipoprotein H2, there were no major differences in the outer membrane protein or lipopolysaccharide patterns when compared with those of previously studied clinical isolates.
Achromobacter xylosoxidans (Alcaligenes xylosoxidans subsp. xylosoxidans) meningitis associated with a gunshot wound
Authors: D'Amato R F , Salemi M , Mathews A , Cleri D J , Reddy G
Published: January 2020

The microbiological and clinical features of a case of Achromobacter xylosoxidans (Alcaligenes xylosoxidans subsp. xylosoxidans) meningitis associated with a gunshot wound are described. To our knowledge, this is the third confirmed case report of meningitis caused by this organism.
Time-resolved fluorometry for the identification of viral DNA in clinical specimens
Authors: Dahlén P , Hurskainen P , Lövgren T , Hyypiä T
Published: January 2020

Time-resolved fluorometry was used for the detection of DNA probes labeled directly with europium (Eu3+) chelate. The sensitivity of this nonisotopic hybridization assay was 100 pg of homologous DNA. Equivalent results with reference tests were obtained in the detection of adenoviruses in clinical specimens.
Multilocus enzyme electrophoresis of Clostridium argentinense (Clostridium botulinum toxin type G) and phenotypically similar asaccharolytic clostridia
Authors: Altwegg M , Hatheway C L
Published: January 2020

Twenty-three strains of Clostridium argentinense, C. subterminale, C. hastiforme, and other phenotypically similar asaccharolytic clostridia recently placed in seven DNA hybridization groups were compared by multilocus enzyme electrophoresis. The three nontoxigenic strains of C. argentinense were most closely related to the toxigenic strains of this species. All nine toxigenic strains of C. argentinense belonging to a single DNA hybridization group had identical enzyme types on the basis of nine enzymes. All other strains except for two derived from the type strain of C. subterminale were differentiable. Overall, there was excellent agreement between DNA relatedness and multilocus enzyme electrophoresis results.
Experience with the use of pronase to eliminate interference factors in the latex agglutination test for cryptococcal antigen
Authors: Gray L D , Roberts G D
Published: January 2020

Cryptococcal antigen titers of 70 cerebrospinal fluid and 57 serum specimens from patients suspected of having cryptococcosis were determined both before and after treatment with pronase. Median titers of cerebrospinal fluid specimens before and after treatment were 128 and 128, respectively; mean geometric titers of these specimens before and after treatment were 102 and 204, respectively. Median titers of the serum specimens before and after treatment were 16 and 512, respectively; mean geometric titers of these specimens before and after treatment were 19 and 631, respectively. The modified latex agglutination test did not detect antigen in any of 50 cerebrospinal fluid and 51 serum specimens from patients not suspected of having cryptococcosis. These results suggest that the pronase modification increases the sensitivity of the latex agglutination test and that the modification be routinely incorporated into it.
Ability of TESTPACK ROTAVIRUS enzyme immunoassay to diagnose rotavirus gastroenteritis
Authors: Chernesky M , Castriciano S , Mahony J , Spiewak M , Schaefer L
Published: January 2020

TESTPACK ROTAVIRUS, a simple 10-min enzyme immunoassay, was compared with electron microscopy and Pathfinder enzyme immunoassay on feces from 172 patients of various ages with gastroenteritis. The percent sensitivities and specificities before blocking with antiserum were as follows: TESTPACK, 100% sensitivity and 99% specificity; Pathfinder, 95% sensitivity and 98% specificity. After blocking, the sensitivity and specificity, respectively, were 100% and 100% for TESTPACK and 95% and 99% for Pathfinder. TESTPACK ROTAVIRUS was more sensitive, but not significantly, than Pathfinder (P greater than 0.1) and the direct electron microscopy technique (P greater than 0.1).
Comparison of sensitivities and specificities of latex agglutination and an enzyme-linked immunosorbent assay for detection of antibodies to the human immunodeficiency virus in African sera
Authors: Francis H L , Kabeya M , Kafuama N , Riggins C , Colebunders R , Ryder R , Curran J , Izaley L , Quinn T C
Published: January 2020

The sensitivities, specificities, and positive and negative predictive values of the Cambridge BioScience Corp. (Worcester, Mass.) human immunodeficiency virus latex agglutination assay were compared by using three different blood preparations. By using the manufacturer's standard test method with diluted sera, the sensitivity of latex agglutination was 100%, the specificity was 99.58%, and the positive and negative predictive values were 99.26 and 100%, respectively. Use of diluted whole blood or undiluted whole blood did not significantly affect the sensitivity (mean, 99.72%), specificity (mean, 99.47%), positive predictive value (mean, 99.07%), or negative predictive value (mean, 99.89%). The latex agglutination assay is a simple, rapid assay for the detection of human immunodeficiency virus that would be useful in Third World countries or other areas where enzyme-linked immunosorbent assays are not available or cannot be used.
Recognition of mycobacterial antigens by sera from patients with leprosy
Authors: Vega-Lopez F , Stoker N G , Locniskar M F , Dockrell H M , Grant K A , McAdam K P
Published: January 2020

Mycobacterium leprae sonic extracts prepared from armadillo-derived bacteria were subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blotting (immunoblotting) procedures and probed with serum or plasma samples from 20 patients with lepromatous leprosy and 14 healthy endemic controls. Five proteins of 33, 25, 18, 15, and 12 kilodaltons (kDa) were frequently recognized; the 33- and 15-kDa proteins were, respectively, recognized with high intensity by 16 and 13 of the 20 samples from patients with leprosy, whereas only one healthy donor had antibodies that recognized the 15-kDa protein. By the use of M. leprae-specific murine monoclonal antibodies it was demonstrated that the 33-, 25-, and 15-kDa antigens were different from those bound by the available murine monoclonal antibodies. The 18- and 12-kDa proteins detected had molecular masses similar to those detected by the corresponding murine monoclonal antibodies. The serum and plasma samples from patients with leprosy were also used to probe Western blots of a soluble extract of M. tuberculosis. They recognized, among others, antigens with molecular weights similar to those detected in the M. leprae antigenic preparations, although with less intensity and at a lower frequency.
Repetitive sequence element cloned from Leptospira interrogans serovar hardjo type hardjo-bovis provides a sensitive diagnostic probe for bovine leptospirosis
Authors: Zuerner R L , Bolin C A
Published: January 2020

A repetitive sequence element was cloned from the primary etiological agent causing bovine leptospirosis in North America, Leptospira interrogans serovar hardjo type hardjo-bovis. This element was used to design a sensitive diagnostic probe which distinguishes hardjo-bovis from other pathogenic leptospires which commonly infect domestic animals in North America and discriminates between hardjo-bovis and the reference strain for serovar hardjo, hardjoprajitno. By using this probe, it was possible to identify infected cattle shedding hardjo-bovis in their urine. This is the first practical demonstration of a cloned DNA probe for leptospirosis, and it provides a sensitive method for studying the transmission and pathogenesis of L. interrogans infections. Control measures for L. interrogans infections may now be improved by rapidly and efficiently identifying infected animals.