bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of Clostridium botulinum, Clostridium argentinense, and related organisms by cellular fatty acid analysis
Authors: Ghanem F M , Ridpath A C , Moore W E , Moore L V
Published: January 2020

On the basis of 686 analyses of 285 strains of Clostridium botulinum, Clostridium argentinense (formerly C. botulinum type G), and phenotypically related organisms, 14 cellular fatty acid (CFA) groups of toxic organisms and 6 CFA groups of nontoxic organisms were delineated. The CFA groups of toxic strains included two of type A, three of proteolytic strains of type B, two of proteolytic strains of type F, one each of nonproteolytic strains of types B, E, and F, and one each of types C alpha, C beta, and D and C. argentinense. The groups of phenotypically similar nontoxic strains included Clostridium sporogenes, Clostridium putrificum, nontoxic strains with phenotypic characteristics similar to those of nonproteolytic strains of C. botulinum types B, E, and F (BEF-like), two groups of nontoxigenic organisms with phenotypic characteristics similar to those of C. botulinum types C and D and Clostridium novyi (CDN-like), and Clostridium subterminale, which has phenotypic characteristics similar to those of C. argentinense. Within the toxin types, 89 to 100% of the strains were correctly identified by CFA analysis, and 74 to 100% of the analyses were correct. Of 36 strains of C. sporogenes, 30 (83%) were correctly identified; 17% of the strains of C. sporogenes were incorrectly identified as C. botulinum type A or B. All analyses of C. putrificum and C. subterminale were correctly identified. There was no significant level of similarity between strains of C. botulinum and phenotypically similar organisms and 85 other species of clostridia or 407 other taxa of gram-positive and gram-negative bacteria. Additionally, the one strain each of Clostridium baratii and Clostridium butyricum previously reported to produce C. botulinum toxin could be differentiated from C.botulinum types as well as from strains of C. baratii and C. butyricum that did not produce neurotoxin.
High prevalence of Helicobacter pylori infection and histologic gastritis in asymptomatic Hispanics
Authors: Dehesa M , Dooley C P , Cohen H , Fitzgibbons P L , Perez-Perez G I , Blaser M J
Published: January 2020

In this study, we estimated the prevalence of Helicobacter pylori infection and histologic gastritis in 58 asymptomatic Hispanic adult volunteers (mean age, 41 years; 59% male) by endoscopic biopsy of the upper gastrointestinal tract. Forty-six subjects (79%) were found to harbor H. pylori in gastric biopsies, and all had histologic gastritis. Four other subjects were found to have gastritis in the absence of H. pylori. Similar prevalences of H. pylori and gastritis were noted in all age groups and also in American-born and immigrant Hispanics. Biopsy data and serologic studies of H. pylori antibodies correlated well. We conclude that H. pylori infection is an almost universal finding in the gastric mucosa of asymptomatic adult Hispanics, regardless of age. The clinical significance of these findings is unknown, but we speculate that H. pylori and its associated gastritis could have a role in the high incidence of gastric carcinoma in Hispanic populations.
Preliminary evaluation of Biolog, a carbon source utilization method for bacterial identification
Authors: Miller J M , Rhoden D L
Published: January 2020

The Biolog Identification System (Biolog, Inc., Hayward, Calif.) is a new bacterial identification method that establishes an identification based on the exchange of electrons generated during respiration, leading to a subsequent tetrazolium-based color change. This system tests the ability of a microorganism to oxidize a panel of 95 different carbon sources. We report on a preliminary investigation of the ability of the instrument to identify, using its computer-driven enzyme immunoassay reader, a diverse group of clinically relevant members of the family Enterobacteriaceae and gram-negative non-Enterobacteriaceae. The Biolog reported identifications (correct or incorrect) for 266 of 352 organisms tested (75.6%). Of the 266 identifications reported, 87.3% were correct at the genus level and 75.6% were correct at the species level at 24 h. In the total study of 352 strains, 46.6% were correct to the species level at 4 h and 57.1% were correct to the species level at 24 h. The error rate was 10.4% after 4 h and 9.6% after 24 h. The Biolog performed well with many genera, but problems were encountered with some strains of Klebsiella, Enterobacter, and Serratia. We found the system to be versatile and easy to use.
Use of immunofluorescence to identify measles virus infections
Authors: Minnich L L , Goodenough F , Ray C G
Published: January 2020

Monoclonal antibody to measles virus was used successfully to identify measles virus antigen directly in clinical specimens, as well as in cell cultures. Pooled nasopharyngeal-throat swab specimens had a higher yield than throat swabs or urine samples for virus detection. Use of A549 cell cultures in the spin amplification vial assay proved to be highly efficient, allowing virus recognition within 1 to 2 days of inoculation. A combination of appropriately collected specimens, which includes a nasopharyngeal-throat swab, direct antigen detection with monoclonal antibody to measles in an indirect immunofluorescence system, and the spin amplification vial assay using A549 cells provides a sensitive and rapid system for isolation and/or identification of measles virus infections.
Immune capture and detection of Borrelia burgdorferi antigens in urine, blood, or tissues from infected ticks, mice, dogs, and humans
Authors: Dorward D W , Schwan T G , Garon C F
Published: January 2020

Current biological and serological techniques for demonstrating infections by Borrelia burgdorferi can be inconclusive. In order to monitor Lyme borreliosis, we developed a rapid and sensitive assay for B. burgdorferi antigens in infected hosts. Polyclonal rabbit antisera were raised against membrane vesicles and an 83-kDa vesicle-associated protein band that was purified from in vitro B. burgdorferi cultures. Immunoglobulin G (IgG) antibodies were recovered from these sera and tested for a species-specific reaction with several geographically diverse Borrelia isolates by immunoblot analysis. Parlodion-coated electron microscope grids were activated with anti-vesicle F(ab')2 fragments and then incubated with confirmed or experimental sources of spirochetal antigens. Such sources included cultured spirochetes; spirochete culture supernatants; samples of urine, blood, or serum from mice, dogs, and humans; triturates of Ixodes ticks; and bladder, spleen, liver, kidney, heart, or brain tissues from infected or control mice. Captured antigens were assayed by immune electron microscopy by using anti-83-kDa IgG antibodies and protein A-colloidal gold conjugates. The results indicated that B. burgdorferi appears to shed surface antigens which are readily detectable in urine, blood, and several organs from infected hosts. Such antigens were detectable in mouse urine at dilutions exceeding 10(-6). Intact spirochetes were frequently observed on grids incubated with blood, spleen, or bladder preparations, and B. burgdorferi was reisolated from the urinary bladders of all experimentally infected mice. These results indicated that B. burgdorferi antigens arise in a variety of host materials. Such antigens can be captured and identified with specific polyclonal antibodies, providing a sensitive assay for monitoring and studying Lyme borreliosis.
Determination of genetic variation within Plasmodium falciparum by using enzymatically amplified DNA from filter paper disks impregnated with whole blood
Authors: Kain K C , Lanar D E
Published: January 2020

A new method which allows the enzymatic amplification of DNA extracted from whole blood dried on filter paper disks is presented. The method was used to study heterogeneity within an erythrocyte-binding antigen (EBA-175) of Plasmodium falciparum. Blood specimens from malaria-infected patients in Southeast Asia and Africa were spotted onto filter paper, dried, and transported for processing. P. falciparum DNA was extracted by boiling the filter paper disks in the presence of Chelex-100 ion-chelating resin, amplified by the polymerase chain reaction, and analyzed for the presence of genetic variation. In all cases examined, plasmodial DNA was successfully amplified and characterized from filter paper disks. Hybridization of the polymerase chain reaction products with internal probes demonstrated simultaneous infection with two strains of P. falciparum in two patients. This technique represents a sensitive and practical field method for the determination of genetic variation within P. falciparum and the study of molecular epidemiology.
Construction of a DNA probe and detection of Actinobacillus pleuropneumoniae by using polymerase chain reaction
Authors: Sirois M , Lemire E G , Levesque R C
Published: January 2020

A 1.5-kb Actinobacillus pleuropneumoniae 4074 DNA fragment from a genomic library was found to hybridization. No cross-hybridization hybridization. No cross-hybridization was detected with DNAs from hemolytic members of the family Pasteurellaceae. From the nucleotide sequence of the putative genomic probe, three primers were synthesized for use in polymerase chain reactions (PCRs), with 31 strains tested by using purified and crude DNA targets. PCR amplification products of 610 and 985 bp were observed in nucleic acids extracted from the 12 known serotypes and a biotype 2 strain. Template DNAs from other gram-negative and gram-positive bacteria, some of them found in the normal flora of swine and the upper respiratory tract, were not amplified by PCR. The only exception was an amplification of a similar 610- or 985-bp sequence in Actinobacillus lignieresii, a species that is closely related to A. pleuropneumoniae but that has never been isolated from swine. Amplification of specific A. pleuropneumoniae sequences by PCR directly from clinical specimens may find applications in the identification of asymptomatic carriers as well as in efforts to eradicate porcine pleuropneumonia.
Sensitive immunoradiometric assay for the detection of Paracoccidioides brasiliensis antigens in human sera
Authors: Ferreira-da-Cruz M F , Galvão-Castro B , Daniel-Ribeiro C T
Published: January 2020

In the present study we report the standardization of an immunoradiometric assay (IRMA) for detection of Paracoccidioides brasiliensis circulating antigens that could be useful in the diagnosis and prognosis of paracoccidioidomycosis. For this purpose we studied the reactivities of P. brasiliensis and other mycotic antigens with rabbit polyclonal anti-P. brasiliensis antibodies (immunoglobulin G) in order to evaluate the sensitivity and specificity of an IRMA for detecting P. brasiliensis antigens. The results were compared with those obtained by the double immunodiffusion test, the standard technique for the serodiagnosis of paracoccidioidomycosis. By using the immunoglobulin G fraction of rabbit antisera (900 ng per well), it was possible to detect up to 3.6 ng (0.12 micrograms/ml) of cellular antigen and 360 ng (12 micrograms/ml) of metabolic antigen in contrast to the double immunodiffusion test that could detect only 12 micrograms (1.2 mg/ml) of both antigens. IRMA was shown to be feasible and very sensitive and may therefore help, together with clinical data, in establishing early diagnosis and assessing disease activity. It could also allow the study of relationships between P. brasiliensis circulating antigens and host defense mechanisms during the disease.
Effect of delays in processing on the survival of Mycobacterium avium-M. intracellulare in the isolator blood culture system
Authors: von Reyn C F , Hennigan S , Niemczyk S , Jacobs N J
Published: January 2020

Concentrations of Mycobacterium avium-M. intracellulare ranging from 10(-1) to 10(3) CFU/ml were added to blood, placed in Isolator tubes, and held at room temperature for intervals ranging from 4 h to 56 days before being processed (centrifugation and culture on Middlebrook 7H10 agar). At all concentrations tested, M. avium-M. intracellulare was recovered after hold times ranging from 4 h to 7 days; the number of final CFU actually increased progressively for hold times of 8 h or more. Hold times of up to 7 days did not increase the time from processing to the first appearance of visible colonies. At an inoculum of 10(2) CFU/ml, M. avium-M. intracellulare was recovered from Isolator tubes processed 56 days after inoculation. Two Isolator blood cultures were drawn from a patient with AIDS; M. avium-M. intracellulare was recovered from the sample processed immediately and from the sample processed after a hold time of 7 days. Since M. avium-M. intracellulare survives for prolonged periods in Isolator tubes, blood cultures may be collected in outpatient settings or in hospitals without mycobacterial culture facilities and shipped to reference laboratories for processing without loss of viability.
Reactivation of Epstein-Barr virus during early infection with human immunodeficiency virus
Authors: Rahman M A , Kingsley L A , Atchison R W , Belle S , Breinig M C , Ho M , Rinaldo C R
Published: January 2020

Reactivation of Epstein-Barr virus (EBV) in early human immunodeficiency virus (HIV) infection was investigated in 49 homosexual men who seroconverted to HIV (cases) as compared with 49 matched controls who remained seronegative to HIV during a longitudinal study. EBV infection was reactivated in cases 6 months, but not 12 months, prior to HIV seroconversion as compared with controls and remained reactivated during 18 months of follow-up after HIV seroconversion, as shown by increases in immunoglobulin (Ig) G antibody titers to EBV early antigen. Antibody titers to EBV viral capsid antigen did not differ between cases and controls prior to the time of seroconversion to HIV but were significantly increased among cases by the first seropositive study visit and remained elevated during the 18 months after HIV seroconversion. Total serum IgG levels were increased in cases at the visit of seroconversion, and during 18 months of follow-up, but did not correlate with enhanced IgG production specific for EBV antigens. Significant decreases in numbers of CD4+ cells and increases in numbers of CD8+ cells during this early phase of HIV infection were not associated with changes in patterns of EBV antibody responses. Reactivation of EBV beginning 6 months before HIV seroconversion may have implications regarding the role of this herpesvirus in the pathogenesis of HIV.
Characterization of Staphylococcus hyicus with the ATB 32 Staph system and with conventional tests
Authors: Lämmler C
Published: January 2020

The ATB 32 Staph system correctly identified 45 of 54 Staphylococcus hyicus cultures isolated from pigs and cattle. The biochemical profiles of the remaining nine cultures were not listed in the product data base. The 40 porcine and 14 bovine cultures resulted in three and seven different biochemical profiles, respectively. In parallel experiments, almost all S. hyicus cultures showed hemolytic reactions on chocolate agar, had CAMP-like reactivities in the zone of lysis of the staphylococcal beta-lysin, and had bacteriolytic properties on Micrococcus luteus cells. In addition, the S. hyicus cultures were unpigmented, were DNase positive, expressed an S. hyicus-specific teichoic acid, and were usually coagulase positive in porcine plasma. Most of the porcine strains were protein A positive, and two porcine cultures were clumping factor positive.
Antimicrobial susceptibility testing of veterinary clinical isolates with the Sceptor System
Authors: Papp J R , Muckle C A
Published: January 2020

The Sceptor System (Becton Dickinson) was compared with an agar dilution method for antimicrobial susceptibility testing of veterinary clinical isolates. The results indicate that the Sceptor System may be used to test gram-positive and fastidious gram-negative bacteria.
Synthetic oligonucleotide probes differentiate respiratory syncytial virus subgroups in a nucleic acid hybridization assay
Authors: Sullender W M , Wertz G W
Published: January 2020

A new approach to respiratory syncytial virus subgroup differentiation has been developed on the basis of the hybridization of subgroup-specific synthetic oligonucleotides with viral mRNA. Two oligonucleotide probes were designed from the nucleotide sequences of an A and a B subgroup respiratory syncytial virus glycoprotein G gene. All 28 virus isolates tested were correctly classified by subgroup with these probes.
Comparison of the new MicroScan Pos MIC Type 6 panel and AMS-Vitek Gram Positive Susceptibility Card (GPS-TA) for detection of high-level aminoglycoside resistance in Enterococcus species
Authors: Szeto S , Louie M , Low D E , Patel M , Simor A E
Published: January 2020

We compared the MicroScan Pos MIC Type 6 panel and AMS-Vitek Gram Positive Susceptibility Card (GPS-TA) to agar dilution screen plates for the detection of high-level aminoglycoside resistance in 182 enterococcal isolates. The specificity of the two commercial systems was 100%, with the exception of one susceptible isolate found to be streptomycin resistant by the Vitek system. The MicroScan and Vitek systems had comparable sensitivities for the detection of gentamicin resistance (90 and 95% respectively) and streptomycin resistance (85 and 78%, respectively). These results suggest that screening tests such as agar dilution screen plates, broth dilution, or disk diffusion should continue to be used to detect high-level gentamicin and streptomycin resistance.
Incidence of toxigenic Campylobacter strains in South Africa
Authors: Bok H E , Greeff A S , Crewe-Brown H H
Published: January 2020

Campylobacter strains can produce a heat-labile cytotonic toxin (CTON) and various cytotoxins (CTOX). Of 22 South African Campylobacter strains tested, 86% were toxigenic (77% produced CTON, 41% produced CTOX, and 32% produced both types) and 14% were toxin negative. Campylobacter jejuni strains were 67% CTON positive and 47% CTOX positive, whereas Campylobacter coli strains were 100 and 29% positive, respectively.
Restriction fragment analysis of a Candida tropicalis outbreak of sternal wound infections
Authors: Doebbeling B N , Hollis R J , Isenberg H D , Wenzel R P , Pfaller M A
Published: January 2020

An apparent single-source outbreak of Candida tropicalis sternal wound infections in eight patients was investigated by utilizing DNA restriction fragment analysis (RFA) with HindIII and BstNI. All eight outbreak isolates appeared to be identical and were easily differentiated from control isolates by DNA RFA. Compared with an arbitrarily selected reference outbreak isolate, greater than or equal to 95% of the bands in the restriction digests identified by a computerized image analysis system from each of the outbreak isolates were identical versus 13 to 53% of the bands in any of the nine control isolates. Outbreak strains were significantly more likely to match the reference outbreak isolate than were controls (P less than 0.0001). The RFA was greatly facilitated by the use of computerized image analysis and confirmed the epidemiologic link between a scrub nurse and the infected patients.
Intermediate human adenovirus type 22/H10,19,37 as a new etiological agent of conjunctivitis
Authors: Noda M , Miyamoto Y , Ikeda Y , Matsuishi T , Ogino T
Published: January 2020

Eight strains of a new intermediate adenovirus were isolated in the course of an investigation of conjunctivitis in Hiroshima City, Japan. The strain was first isolated in July 1986. All eight strains were isolated from conjunctival swab samples from patients with conjunctivitis, mainly epidemic keratoconjunctivitis. The virus was typed as adenovirus type 22 in neutralization tests and was related closely to types 10, 19, and 37 in hemagglutination inhibition tests. The DNA cleavage patterns of the eight strains with nine restriction endonucleases were the same with one exception but different from those of the above serologically related species. We conclude that the intermediate adenovirus is a new etiological agent of conjunctivitis, mainly epidemic keratoconjunctivitis.
Comparison of ribotyping with conventional methods for the type identification of Enterobacter cloacae
Authors: Garaizar J , Kaufmann M E , Pitt T L
Published: January 2020

An Escherichia coli rRNA probe was compared with a combination of O serotyping, phage susceptibility, and biotype pattern for the type identification of strains of Enterobacter cloacae. Forty-five isolates of E. cloacae from 36 patients in nine hospitals were examined. By conventional typing, only 26 (57.7%) could be assigned to a specific serotype and 6 (13.3%) were autoagglutinating owing to rough lipopolysaccharide antigens. All isolates could be assigned to one of three biotypes, but many phage sensitivity patterns were evident. Twenty-nine distinct strains were identified by combined typing. Probing of EcoRI and BamHI digests of chromosomal DNA with a cDNA copy of E. coli rRNA proved to be highly discriminating between strains. Thirty different ribotypes based on 28 bands were recorded. Overall, agreement between the ribotyping and combined typing methods was good (84.4%), and discrepancies were generally confined to serologically unclassifiable strains and variability in biotype codes. Ribotyping was reproducible, and five of six pairs of isolates from the same and different patients gave identical hybridization profiles on separate occasions. We conclude that ribotyping is a highly discriminatory and reproducible method for the typing of E. cloacae, but in most outbreaks it offers little increase in discrimination over traditional methods.
Detection of human papillomavirus DNA in genital lesions by using a modified commercially available in situ hybridization assay
Authors: Meyer M P , Markiw C A , Matuscak R R , Saker A , McIntyre-Seltman K , Amortegui A J
Published: January 2020

A modified, commercially available DNA-DNA in situ hybridization test that uses biotinylated probes for the identification of human papillomavirus (HPV) DNA types 6/11, 16/18, and 31/33/35 was evaluated. HPV DNA was detected in 314 of 787 (40%) histologically abnormal genital biopsy specimens by using the ViraType in situ assay (Life Technologies, Gaithersburg, Md.), in which the hybridization time was increased from 2 to 16 h. Ninety percent of positive condyloma acuminata specimens contained HPV type 6/11 DNA. The prevalences of HPV DNA for cervical intraepithelial neoplasia I, II, and III lesions by this in situ hybridization test were 42, 54, and 55%, respectively. The combined prevalence of HPV type 16/18 and 31/33/35 DNAs increased with the severity of the lesion, while the prevalence of type 6/11 DNA decreased. HPV type 6/11 DNA was found only in 1 of 16 (6%) positive cervical intraepithelial neoplasia III specimens. HPV type 16/18 and 31/33/35 DNA was detected in 11 of 16 (69%) and 4 of 16 (25%) in situ hybridization-positive cervical intraepithelial neoplasia III specimens, respectively. Thus, the observation that certain "higher-risk" HPV genotypes are associated with upper-grade cervical precancer lesions was confirmed by this commercial hybridization system. In general, the assay was found to be well suited for use in the clinical laboratory. The ViraType in situ procedure modified for a longer hybridization time may be helpful in identifying lesions containing higher-risk HPV strains.
Model of recurrent pulmonary aspergillosis in rats
Authors: Niki Y , Bernard E M , Edwards F F , Schmitt H J , Yu B , Armstrong D
Published: January 2020

Male Sprague-Dawley rats were treated with cortisone acetate and fed a low-protein diet for 3 weeks. At the end of week 2, animals were infected intratracheally with 10(5) conidia of Aspergillus fumigatus H11-20. Despite discontinuation of steroids and the low-protein diet 1 week after the infection, 94% of controls died of invasive pulmonary aspergillosis within 3 weeks postinfection. When rats were treated with a single dose of 1.6 mg of aerosolized amphotericin B per kg of body weight 48 h prior to the infection, mortality was reduced to 11% within 3 weeks postinfection. Despite apparent good health and rapid weight gain, all survivors showed multiple lesions in histopathological sections of the lungs, and 10(3) to 10(4) CFU of aspergilli was recovered from cultures of their lungs. With discontinuation of immunosuppression, the infection was slowly cleared; however, when cortisone acetate was restarted during week 5, reactivation of progressive invasive pulmonary aspergillosis was observed. On the basis of these results, we conclude that a single low dose of aerosolized amphotericin B prophylaxis is effective in preventing an exogenous aspergillus infection of the lung. Additional therapy is needed to prevent recurrent infection caused by endogenous aspergilli when immunosuppression is resumed.
DNA polymorphism in strains of Listeria monocytogenes
Authors: Carriere C , Allardet-Servent A , Bourg G , Audurier A , Ramuz M
Published: January 2020

DNA polymorphism in 35 Listeria monocytogenes strains belonging to serovars 1/2a, 1/2b, 1/2c, and 4b was studied by genomic DNA digestion. The restriction endonucleases ApaI and NotI, which cleave DNA at rare sequences, were used, and DNA fragments were analyzed by pulsed-field gel electrophoresis. Restriction fragment length polymorphism varied among different serovars and was used for epidemiological studies, but serovar 1/2c isolates could not be analyzed because their restriction patterns were indistinguishable. The genome sizes were calculated by addition of the sizes of the ApaI fragments and were found to be about 2,660 kb for serovar 1/2a strains, 2,640 kb for serovar 1/2b strains, and 2,710 kb for serovar 4b strains but only 2,340 kb for serovar 1/2c strains. This last group therefore appears to differ from the other serovar strains by the absence of restriction fragment length polymorphism and a chromosome that is 15% shorter, suggesting that strains of serovar 1/2c have quite recently emerged.
Evaluation of a synthetic-peptide enzyme-linked immunosorbent assay for immunoglobulin M to human parvovirus B19
Authors: Fridell E , Cohen B J , Wahren B
Published: January 2020

A synthetic peptide corresponding to a part of the virus protein 1-virus protein 2 overlapping region of human parvovirus B19 was used in an indirect enzyme-linked immunosorbent assay. Antibodies of the immunoglobulin (Ig) M class were measured in serum samples from patients with erythema infectiosum and controls. In comparison with an IgM assay using native B19 viral antigen, the peptide antigen assay was 92% sensitive and 87% specific. B19 IgM reactivities were seen in a limited number of children with other viral diseases. Specific IgM reactivities to short synthetic viral peptides have previously been reported only with Epstein-Barr virus. Since other sources of viral antigen are limited, the peptide antigen assay may be a useful alternative for the diagnosis of B19-associated disease in human beings.
Seropositivity to Helicobacter pylori: lack of association with length of hospitalization
Authors: Thoene J G , Burken M I , Hopkins R J , Russell R G , Morris J G
Published: January 2020

To examine the possibility of nosocomial spread of Helicobacter pylori, a serosurvey (n = 238) was conducted at Perry Point Department of Veterans Affairs Medical Center, an institution providing both acute and chronic care. We hypothesized that if significant nosocomial transmission was occurring, seropositivity (as measured by enzyme-linked immunosorbent assay [ELISA]) would correlate with length of stay in the facility. Whether treated as a continuous or dichotomous variable, the ELISA results did not correlate significantly with length of stay even after adjustments were made for age, race, antibiotic use, gastrointestinal instrumentation, and diagnoses by using multiple-regression models. Age was found to be a significant risk factor for a higher ELISA optical density value. A history of chronic obstructive pulmonary disease was significantly protective among internal medicine ward patients in adjusted analysis; black race was a significant risk factor among psychiatry ward patients. Our results confirm the association of H. pylori infection with age but provide no indication that extended hospitalization is a risk factor for infection.
Immunologic function in a cohort of human immunodeficiency virus type 1-seropositive and -negative healthy homosexual men
Authors: Klimas N G , Caralis P , LaPerriere A , Antoni M H , Ironson G , Simoneau J , Schneiderman N , Fletcher M A
Published: January 2020

The study objectives were to determine the early effects of human immunodeficiency virus type 1 (HIV-1) infection on both phenotypic and functional immunologic markers in healthy homosexual men, to ascertain the relationships of these markers to each other, and to discover which markers were affected by enrollment in an AIDS study in which HIV-1 serostatus would be determined. The major findings were as follows. (i) The CD4/CD8 ratio and lymphocyte proliferative response to pokeweed mitogen were the characteristics most affected by early HIV-1 infection. (ii) The loss in CD4 cells observed in the HIV-1-positive homosexual men was entirely due to diminished numbers of the memory subset. CD4+ CD29+. The reciprocal subset of CD4, CD4+ CD45RA+, did not differ in the two groups of homosexual men at either time point or in the controls. (iii) Prior to learning their HIV-1 serostatus, HIV-1 antibody-negative risk-group males had lower phytohemagglutinin (PHA) responses than the controls did. In the assays following notification of their seronegativity, however, these men had PHA values which were not different from those of the controls. In the HIV-1-positive group, the responses to both PHA and pokeweed mitogen were below those of both HIV-1-negative groups and did not change after serostatus notification. (iv) The activity of natural killer cells was lower in the risk-group men than in the controls at both pre- and postdiagnosis but was not related to HIV-1 serostatus. (v) In this cohort of homosexual men, the CD4/CD8 ratio correlated significantly with the functional measures of immunologic status in the HIV-1-positive men, but not in the HIV-1-negative men.
Comparison of the autoSCAN-W/A rapid bacterial identification system and the Vitek AutoMicrobic system for identification of gram-negative bacilli
Authors: Pfaller M A , Sahm D , O'Hara C , Ciaglia C , Yu M , Yamane N , Scharnweber G , Rhoden D
Published: January 2020

The autoSCAN-W/A (W/A; Baxter MicroScan, West Sacramento, Calif.) with the new fluorometric Rapid Neg Combo 1 (RNC) panel is a fully automated fluorometric system for identification of both enteric and nonenteric gram-negative bacilli within 2 h. We compared the W/A with the Vitek AutoMicrobic System (Vitek AMS; Vitek Systems, Inc., Hazelwood, Mo.) for identification of 383 clinical isolates of gram-negative bacilli. The API 20E (Analytab Products, Plainview, N.Y.) and conventional biochemical testing were used as the reference systems. The W/A correctly identified 336 isolates (87.7%) to the species level and classified an additional 29 isolates (7.6%) as correct with low probability (overall identification = 95.3%); the Vitek AMS correctly identified 355 isolates (92.7%) to the species level and classified an additional 8 isolates (2.1%) as correct with low probability (overall identification = 94.8%). A common set of 134 isolates of gram-negative bacilli was tested in both participating laboratories as a means of assessing interlaboratory agreement with both the W/A and the Vitek AMS. The overall agreements between the two laboratories were 86% with the W/A and 92% with the Vitek AMS. The W/A performed comparably to the Vitek AMS for identification of most gram-negative bacilli, actually exceeding the Vitek AMS for identification of nonenteric bacilli. Rapid time to identification and a high level of automation make the W/A an attractive system for clinical microbiology laboratories.
False-positive Chlamydiazyme results during urine sediment analysis due to bacterial urinary tract infections
Authors: Demaio J , Boyd R S , Rensi R , Clark A
Published: January 2020

Our study examined whether urinary tract infections (UTIs) would cause false-positive results when urine sediment was tested with the Chlamydiazyme (CZ) system. Thirty-six infected urine samples and fifteen controls were studied. All controls were negative. Forty-seven percent of Escherichia coli UTIs (n = 30) and 100% of Klebsiella pneumoniae UTIs (n = 4) were positive on CZ testing of urine sediment. Nine E. coli UTIs positive by CZ were negative by direct fluorescent-antibody staining. When suspensions of the pure cultures were analyzed, 47% of E. coli and 100% of K. pneumoniae samples were CZ positive. False-positive results were not related to organism biotype or urine characteristics, including pH, specific gravity, and leukocyte count. We conclude that the presence of a UTI and also bacterial contamination must be ruled out prior to urine sediment testing.
Effect of Tween 80 on formation of the superficial L1 layer of the Mycobacterium avium-Mycobacterium intracellulare complex
Authors: Masaki S , Sugimori G , Okamoto A , Imose J , Hayashi Y
Published: January 2020

The effects of Tween 80 supplementation of liquid culture medium on the formation of the superficial L1 layer of the Mycobacterium avium-Mycobacterium intracellulare complex (MAC) were examined by serological and scanning electron microscopic experiments. Specific antiserum to the glycopeptidolipids on the L1 layer of M. avium S-139, made in a rabbit, was used for seroagglutination reactions with antigens prepared from strain S-139 grown in medium supplemented with various levels of Tween 80 (0, 0.05, 0.5, 5, and 50 mg/ml). The agglutination titers gradually decreased as the concentration of Tween 80 rose. Scanning electron microscopy showed that the fibrillar materials consisting mainly of glycopeptidolipids on the L1 layer of strain S-139 also disappeared with increases in the concentration of Tween 80. In addition, there was no obvious correlation between (i) the plasmid DNAs and serotypes of MAC and (ii) formation of the L1 layer of MAC. It is therefore concluded that Tween 80 used to supplement liquid culture medium affects formation of the L1 layer, which has been considered to be one of the pathogenic factors of MAC.
Evaluation of monoclonal antibody-based capture enzyme immunoassays for detection of specific antibodies to measles virus
Authors: Erdman D D , Anderson L J , Adams D R , Stewart J A , Markowitz L E , Bellini W J
Published: January 2020

Monoclonal antibodies to the hemagglutinin protein, fusion protein, phosphoprotein, matrix protein, and nucleoprotein of measles virus were evaluated as detector antibodies in capture enzyme immunoassays (EIAs) for the detection of specific serum immunoglobulin G (IgG), IgA, and IgM antibodies to measles virus. A pool of monoclonal antibodies to hemagglutinin protein and nucleoprotein proved optimal and was further evaluated. Specific IgM was detected in 97% of adolescents with clinical measles, 97% of infants 3 weeks postvaccination, and less than 1% of normal serum specimens. Specific IgA antibodies were found in 97% of adolescents with clinical measles, 97% of infants 3 weeks postvaccination, and less than 1% of normal serum specimens. Specific IgA antibodies were found in 97% of clinical measles cases and vaccinees, in 26% of healthy persons, and in 36% of infants 8 months postvaccination; consequently, IgA antibodies were not a useful indicator of recent measles infection. A significant increase in IgG antibodies between paired specimens was detected in 92% of clinical cases and all vaccinees. Only 59% of infant specimens had persistent IgG antibodies as detected by capture EIA at 8 months postvaccination, whereas all specimens had antibodies as detected by hemagglutination inhibition and plaque neutralization. An alternative indirect EIA, in which antigen was directly absorbed to the solid phase, was more sensitive than the capture design, detecting IgG antibodies in all infants postvaccination. When standardized with a microneutralization assay for the detection of persistent antibodies, the indirect IgG EIA gave predictive values for positive and negative tests exceeding 90%. Our capture IgM and indirect IgG EIAs provide a practical combination of serologic tests for the determination of acute measles virus infection and past exposure to measles virus or vaccine, respectively.
Characterization of serogroup A and B strains of Neisseria meningitidis with serotype 4 and 21 monoclonal antibodies and by multilocus enzyme electrophoresis
Authors: Wedege E , Caugant D A , Frøholm L O , Zollinger W D
Published: January 2020

The reactions of serogroup A strains of Neisseria meningitidis with one monoclonal antibody specific for serotype 21 and three different monoclonal antibodies specific for serotype 4 were compared with those of serogroup B strains previously assigned to serotype 4. Antibody binding was studied by enzyme-linked immunosorbent assay (ELISA), dot blotting, and immunoblotting. Characterization of the isolates by the electrophoretic mobilities of 14 metabolic enzymes showed 50 multilocus enzyme genotypes. All except two genotypes fell into three distinct clusters: I, IIa and IIb. The enzyme genotypes of serogroup B strains were mainly in cluster I, and 88% of the serogroup A strains had genotypes in clusters IIa and IIb. Serogroup B strains generally reacted with all three serotype 4 monoclonal antibodies in ELISA and dot blotting but with only two in immunoblots. Serogroup A strains showed two different reactions in the blotting methods: either binding of the serotype 21 antibody only or binding of this and two of the three serotype 4 monoclonal antibodies. Strains of the first pattern were in clusters I and IIa, whereas all but two strains in cluster IIb were of the second pattern. In ELISA, an additional reaction of two of the serotype 4 monoclonal antibodies with serogroup A isolates was observed. The different binding of these two monoclonal antibodies in ELISA and the blotting methods appeared to result from heat inactivation of the meningococcal cells and use of detergent-containing reagents in ELISA. The results show that the serotype of serogroup A strains is distinct from serotype 4 of serogroup B strains.
Molecular epidemiology of Staphylococcus haemolyticus strains isolated in an Albanian hospital
Authors: Renaud F , Etienne J , Bertrand A , Brun Y , Greenland T B , Freney J , Fleurette J
Published: January 2020

A recent outbreak of erythroderma in young children in an Albanian hospital was investigated. The etiology was not established, but Staphylococcus haemolyticus was frequently isolated from the affected children and from staff working in the same unit. Possible relationships among the isolates were investigated by using classical techniques (biotype, antimicrobial susceptibility, and extrachromosomal DNA pattern) and by restriction endonuclease analysis (REA) of total DNA. Control isolates of proven pathogenicity from hospitalized patients in Lyon, France were subjected to the same procedures. Distinct REA patterns were obtained after digestion with two enzymes in 7 of 10 isolates from five affected children. Six distinct patterns were observed in nine isolates from six staff members; two REA patterns from patient isolates and two from staff members were identical, and these were distinguishable by the other markers examined. Only two different REA patterns were found in the pathogenic control isolates despite the use of a third additional enzyme. Again, the isolates with the same REA patterns could be distinguished by their plasmid profile or antimicrobial resistance profile. REA of total DNA used in combination with other markers indicated that the Albanian isolates differed considerably, whereas the French pathogenic isolates showed little variability.
Detection of the Lyme disease bacterium, Borrelia burgdorferi, by using the polymerase chain reaction and a nonradioisotopic gene probe
Authors: Wise D J , Weaver T L
Published: January 2020

A 419-bp region of the flagellin gene sequence of Borrelia burgdorferi was used as a target for the polymerase chain reaction. With a nonradioactively labeled gene-specific probe, sensitivity to as few as 1 to 10 spirochetes was observed. The targeted gene fragment was conserved in the American and European strains of B. burgdorferi tested and among several other pathogenic borreliae.
Cross-reactive antibodies induced by a monovalent influenza B virus vaccine
Authors: Levandowski R A , Gross P A , Weksler M , Staton E , Williams M S , Bonelli J
Published: January 2020

Influenza viruses related to the markedly antigenically divergent strains B/Yamagata/16/88 and B/Victoria/2/87 are circulating in human populations. Adults develop cross-reacting antibodies against recent and earlier influenza B virus strains after vaccination with B/Yamagata/16/88, probably because of previous influenza B virus infections or immunizations. Vaccines containing B/Yamagata/16/88 should adequately protect adults against B/Victoria/2/87 infections.
Use of a siderophore detection medium, ethylene glycol degradation, and beta-galactosidase activity in the early presumptive differentiation of Nocardia, Rhodococcus, Streptomyces, and rapidly growing Mycobacterium species
Authors: Fiss E , Brooks G F
Published: January 2020

A simplified scheme for the presumptive early identification of Nocardia, Rhodococcus, rapidly growing Mycobacterium, and Streptomyces species is presented. The Nocardia and Streptomyces spp. and the Mycobacterium spp. were positive. The spp. were positive for siderophore activity, but only 25% of the Rhodococcus spp. were positive. The Rhodococcus and Mycobacterium spp. were negative for beta-galactosidase, while the Nocardia and Streptomyces spp. were positive. The Nocardia and Streptomyces spp. and the Mycobacterium spp. were negative for ethylene glycol degradation, while 75% of the Rhodococcus spp. were positive. In combination, these tests were useful for differentiating Mycobacterium, Rhodococcus, and Nocardia species but did not differentiate Nocardia from Streptomyces species.
Evaluation of a rapid screening test for detecting group B streptococci in pregnant women
Authors: Granato P A , Petosa M T
Published: January 2020

The QUIDEL Group B Strep Test is an enzyme immunoassay (EIA) that was compared with culture for the rapid detection of moderate to high levels of group B streptococci (GBS) colonization in pregnant women. A total of 331 pregnant women were included in the study protocol, and GBS were cultured from 19 of these patients in moderate or greater amounts (incidence of 5.7%). Compared with culture, the EIA had a sensitivity, specificity, and positive and negative predictive values of 89, 99, 89, and 99%, respectively. With a sensitivity of 89%, the 95% confidence interval for this assay is 88 to 90%. The QUIDEL EIA test can be performed in less than 10 min and appears to be a reliable method for detecting moderate or greater amounts of GBS in vaginal or cervical specimens.
Antigenic properties of Borrelia burgdorferi isolated from Ixodes ovatus and Ixodes persulcatus in Hokkaido, Japan
Authors: Masuzawa T , Okada Y , Yanagihara Y , Sato N
Published: January 2020

Spirochete strains HP3 and HO14, isolated from Ixodes persulcatus and I. ovatus in Hokkaido in 1989, were the first isolates of Borrelia burgdorferi, the etiological agent of Lyme disease, to be recognized in Japan. Antigenic properties of the Japanese strains were compared with those of the strains isolated in the United States (B31 and 297) and Europe (IRS, P/Gau, P/Bi, 2/B45, and 3/B56) by Western blotting (immunoblotting), by using monoclonal antibodies (MAbs) against strains B31 and P/Bi. The Japanese strains reacted with MAb U40 against the 41-kDa antigen. MAb E34a31 against Osp A reacted with all the strains tested except for strain HP3. Furthermore, MAb U31b against Osp A reacted with all the American and European strains but did not react with the Japanese strains. When MAbs against Osp B were used, MAb E34b reacted only with European strains and MAb U34b reacted only with the American strains. However, neither showed reactivity to two Japanese strains. MAb E60 against 60-kDa antigen reacted with all the U.S. and European strains and strain HP3 but did not react with Japanese strain HO14. These results indicate that the antigenicity of the Japanese strains isolated from two species of ixodid ticks is different from that of the strains isolated in the United States and Europe. It is suggested that the Japanese strains are much more suitable than the U.S. or European strains as the antigen source for the serodiagnosis of Lyme disease in Japan.
Identification of genomic clonal types of Actinobacillus actinomycetemcomitans by restriction endonuclease analysis
Authors: Han N , Hoover C I , Winkler J R , Ng C Y , Armitage G C
Published: January 2020

To evaluate its utility in discriminating different strains, restriction endonuclease analysis was applied to 12 strains of Actinobacillus actinomycetemcomitans (3 serotype a, 5 serotype b, and 4 serotype c strains). DNA isolated from each strain was digested by 12 different restriction endonucleases, and the electrophoretic banding patterns of the resulting DNA fragments were compared. The DNA fragment patterns produced by SalI, XhoI, and XbaI for the 12 A. actinomycetemcomitans strains were simple (less than 30 bands) and allowed us to recognize easily 10 distinct genomic clonal types. The three serotype a strains exhibited distinctly different clonal types from one another, the five serotype b strains exhibited an additional four distinct clonal types, and the four serotype c strains showed another three different clonal types. The other endonucleases tested were less useful in typing A. actinomycetemcomitans. We conclude that restriction endonuclease analysis is a powerful tool for typing and discerning genetic heterogeneity and homogeneity among A. actinomycetemcomitans strains. It should, therefore, be very useful for epidemiologic studies.
Clinical and microbiological observations on CDC group DF-3, a gram-negative coccobacillus
Authors: Gill V J , Travis L B , Williams D Y
Published: January 2020

Sequential stool cultures submitted for routine culture were screened for the presence of CDC group DF-3. Of 690 specimens, 11 (1.6%) yielded moderate to heavy growth of DF-3. Information on the 11 patients from whom these specimens were obtained showed that 4 had a history of prolonged diarrheal disease that resolved after specific therapy to eradicate DF-3, while for the other 7 patients no clear role could be established. Microbiological characterization of the stool isolates and 10 CDC strains of DF-3 suggested the presence of two subtypes within the group. Antibiotic susceptibility studies showed DF-3 to be relatively resistant to a wide variety of antibiotics.
Longitudinal study of the microbiology of endemic trachoma
Authors: Taylor H R , Siler J A , Mkocha H A , Muñoz B , Velez V , Dejong L , West S
Published: January 2020

A longitudinal study of trachoma in 100 members of nine Tanzanian families was conducted to assess the sources of variation in the laboratory identification of trachoma and the changes that might occur over time. Multiple conjunctival swabs were collected every 3 months for 1 year and examined by direct fluorescent-antibody cytology (DFA), enzyme immunoassay, or microimmunofluorescence serology for tear antichlamydial antibodies. DFA specimens collected 5 min apart had a discordance rate of 10% and this is attributable to sampling variation. DFA specimens collected 2 days or more apart show a 25% discordance rate. This suggests a biologic variation in shedding in addition to sampling variation. Good correlation existed between the DFA and the enzyme immunoassay. Tear serology was quite specific in predicting the presence of clinical disease and correlated with the other two antigen detection tests, although it does not seem to offer any practical advantages. These studies indicate that there is considerable variation in the shedding of chlamydia by people living in trachoma-endemic areas.