bluuebunny/crossref_metadata_2025 huggingface dataset:
Use of a synthetic oligonucleotide probe to detect strains of non-serovar O1 Vibrio cholerae carrying the gene for heat-stable enterotoxin (NAG-ST)
Authors: Hoge C W , Sethabutr O , Bodhidatta L , Echeverria P , Robertson D C , Morris J G
Published: January 2020

A synthetic oligonucleotide probe was developed to identify the gene for the heat-stable enterotoxin (NAG-ST) of non-serovar O1 Vibrio cholerae. Of 103 non-O1 V. cholerae isolates from Thailand, 31 isolates from Mexico, and 47 isolates from patients in the United States, only 7 (all from Thailand) hybridized with the probe. Probe-positive strains produced significantly higher fluid accumulations in infant mice than probe-negative strains.
Evaluation of the indoxyl acetate hydrolysis test for the differentiation of Campylobacters
Authors: Hodge D S , Borczyk A , Wat L L
Published: January 2020

Indoxyl acetate hydrolysis is a rapid, inexpensive differential test which can be performed easily to help identify campylobacter. A total of 571 Campylobacter cultures, including atypical variants, representing 10 species was tested.
Spontaneous peritonitis caused by Enterococcus faecium
Authors: Pascual J , Sureda A , Lopez-San Roman A , Barcena R , De Rafael L , Hernandez-Cabrero J , Boixeda D
Published: January 2020

Three cases of spontaneous peritonitis caused by Enterococcus faecium are presented. The underlying condition was alcoholic cirrhosis in each case. This enterococcal species has never before been reported as a cause of spontaneous bacterial peritonitis. Two patients responded to therapy. The development of enterococcal peritonitis and the cases documented in the literature are briefly reviewed. Taxonomic problems with pathogenic, clinical, and therapeutic implications are discussed.
Evaluation of the ATB 32 A system for identification of anaerobic bacteria isolated from clinical specimens
Authors: Looney W J , Gallusser A J , Modde H K
Published: January 2020

A new miniaturized 4-h method for the identification of anaerobic bacteria, ATB 32 A (API System SA, Montalieu Vercieu, France), was evaluated against conventional methods of identification. The evaluation was done by using 260 recent clinical isolates and 21 reference strains of anaerobic bacteria. All reference strains were correctly identified and did not figure in the detailed analysis. Of the 140 gram-negative bacilli, 90.6% of Bacteroides spp. and 95.5% of Fusobacterium spp. were correctly identified to the species level, with an additional 8.4% of the Bacteroides spp. being identified to the genus level. Clostridia were correctly identified in 85.9% of cases, with an additional 9.9% being identified to the genus level. Peptostreptococci were correctly identified in 91.6% of cases. The 4 strains of Actinomyces spp. were all identified correctly, as were 10 of the 11 strains of Propionibacterium spp. A total of 3.1% of strains were not identified by ATB 32 A, while for 1.9% of strains, completely false identifications were obtained. Estimation of the individual preformed enzyme results may pose problems, although these decrease with familiarity with the system. With certain enzyme profiles, additional testing was necessary to arrive at an identification; however, there was no requirement for gas-liquid chromatography. If certain additions are made to the data base and the difficulties of determination of organisms to the species level among the non-Bacteroides fragilis (sensu stricto) members of the B. fragilis group can be reduced, this system holds promise as a reliable standardized alternative for the identification of anaerobic bacteria in clinical laboratories.
Molecular distinctions among clinical isolates of Mycoplasma pneumoniae
Authors: Su C J , Dallo S F , Baseman J B
Published: January 2020

Restriction enzyme fingerprinting of genomic DNA and Southern blots probed with subclones of the Mycoplasma pneumoniae cytadhesin P1 gene were used to characterize clinical isolates of M. pneumoniae. On the basis of the examination of 29 individual M. pneumoniae isolates, two distinct groups were established. Group 1, which displayed a 12-kilobase band following DNA digestion with HindIII, consisted of strain M129-B16 and three others obtained in the state of Washington during the 1960s. The remaining M. pneumoniae strains belonged to group 2, which lacked the 12-kilobase band and included samples from the 1940s, 1970s, and 1980s. This category also included the only M. pneumoniae strain isolated from the synovial fluid of an arthritic patient.
Use of immunoblotting to detect Aspergillus fumigatus antigen in sera and urines of rats with experimental invasive aspergillosis
Authors: Yu B , Niki Y , Armstrong D
Published: January 2020

Immunoblotting was used to detect Aspergillus fumigatus antigen in sera and urines of immunosuppressed rats experimentally infected with A. fumigatus. Organisms were administered by both intravenous and intratracheal injections. Intravenously infected rats developed disseminated aspergillosis, but intratracheally infected rats developed pulmonary disease only. Fungal cultures of blood and urine samples from infected rats were negative. In the urines of intravenously infected rats, antigen was detected 24 to 48 h after infection; in the urines of intratracheally infected animals, antigen was detected on days 4 to 5 after infection. Antigen in serum was detected later than antigen in urine was. Following sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting of serum and urine samples, the most strongly reacting antigenic materials were found in the 88-, 40-, 27-, and 20-kilodalton regions. These dominant antigens appeared to be the same as those of control antigens prepared from A. fumigatus grown in vitro. Rabbit antiserum to Aspergillus filtrate antigen was found to be more immunoreactive than antiserum to mycelial or conidial antigen. No mycelium-specific antigens were detected.
Comparative evaluation of nonradiometric BACTEC and improved oxoid signal blood culture systems in a clinical laboratory
Authors: Daley C , Lim I , Modra J , Wilkinson I
Published: January 2020

The BACTEC NR660 blood culture system, which uses infrared spectroscopy to detect carbon dioxide generated by bacterial growth, was compared with the new medium formulation of the Oxoid Signal system. Two trials were conducted: a comparative study of 88 organisms in simulated blood cultures and a clinical trial of 3,321 paired patient blood culture samples. Both trials showed that overall the BACTEC system performed better in the recovery of organisms. The Oxoid system was unable to detect by signal the growth of the majority of yeasts, nonfermentative gram-negative bacilli, Neisseria meningitidis, Nocardia spp., and Corynebacterium jeikeium. There were no significant differences in the yield of Staphylococcus spp., members of the family Enterobacteriaceae, Streptococcus spp., or anaerobic organisms. BACTEC detected growth more quickly than did the Oxoid system; 61% of the isolates were detected by BACTEC at 24 h, while 49% of the isolates were detected by Oxoid. The Oxoid system had a high proportion (58.5%) of false-positives, compared with 7.7% for the BACTEC system. Despite the new medium formulation of the Oxoid system, its performance is still not equivalent to that of the BACTEC system.
Isolation by a sensitive centrifugation cell culture system of 52 strains of spotted fever group rickettsiae from ticks collected in France
Authors: Péter O , Raoult D , Gilot B
Published: January 2020

Boutonneuse fever caused by Rickettsia conorii is transmitted mainly by the brown dog tick, Rhipicephalus sanguineus. We collected 540 ticks in Marseille, France, and tried to isolate as many strains of rickettsia as possible. Ticks were evaluated for the presence of rickettsia by the hemolymph test and by a new culture system, the centrifugation-shell vial technique. We avoided contamination in the culture system. Prior to ticks being submitted to the hemolymph test, they were disinfected. Only 5.6% (27 of 478) of the cultures were contaminated. A drop of hemolymph from each of 478 R. sanguineus ticks was cultured in two shell vials, and another drop was stained by the Gimenez method or indirect immunofluorescence. Since Gimenez staining in our hands was not satisfactory, comparison of the hemolymph test and culture is based on the results of indirect immunofluorescence. Thus, 50 of 369 (13.5%) examined ticks were hemolymph test positive, and 44 (11.9%) cultures were positive. After disinfection, another pool of 62 ticks were examined by the hemolymph test. The ticks were kept individually in a sterile environment. A few days later, the hemolymph of these ticks was collected again and cultured. The contamination rate was not significantly higher (6.4%) than in the above-described conditions. It allowed us to isolate eight more strains. Thus, we recommend screening ticks with the hemolymph test and culturing only the hemolymph test-positive ticks.
BacT/Alert: an automated colorimetric microbial detection system
Authors: Thorpe T C , Wilson M L , Turner J E , DiGuiseppi J L , Willert M , Mirrett S , Reller L B
Published: January 2020

BacT/Alert (Organon Teknika Corp., Durham, N.C.) is an automated microbial detection system based on the colorimetric detection of CO2 produced by growing microorganisms. Results of an evaluation of the media, sensor, detection system, and detection algorithm indicate that the system reliably grows and detects a wide variety of bacteria and fungi. Results of a limited pilot clinical trial with a prototype research instrument indicate that the system is comparable to the radiometric BACTEC 460 system in its ability to grow and detect microorganisms in blood. On the basis of these initial findings, large-scale clinical trials comparing BacT/Alert with other commercial microbial detection systems appear warranted.
Immunoglobulin E and G4 antibodies in cysticercosis
Authors: Short J A , Heiner D C , Hsiao R L , Andersen F L
Published: January 2020

The importance of immunoglobulin G (IgG) subclass responses in different infections has been elucidated for a number of organisms, but few parasitic organisms have been examined in this regard. In the current study, quantitative radioimmunoassays were used to examine the IgE and IgG4 subclass responses to larval Taenia solium. Patients were divided into clinically infected (CI) and probably uninfected (PU) groups. Unexposed normal subjects were used as controls. The CI group had elevated geometric mean levels of total IgE in serum (28.6 IU/ml) and specific IgG4 antibodies (438.8 arbitrary units [AU]/ml) compared with controls (8.3 IU/ml and 50.1 AU/ml, respectively). The CI group also had significantly elevated levels in cerebrospinal fluid of total IgG4 (18.6 micrograms/ml) and specific IgG4 antibodies (86.0 AU/ml) compared with the PU group (2.5 micrograms/ml and 1.6 AU/ml, respectively). There was no specific IgE antibody response detected in either the CI or PU patient group. The marked IgG4 response of CI patients to T. solium merits further investigation.
Natural habitat of Cryptococcus neoformans var. gattii
Authors: Ellis D H , Pfeiffer T J
Published: January 2020

Environmental isolations have established that Cryptococcus neoformans var. gattii appears to have a specific ecological association with Eucalyptus camaldulensis. So far, we have isolated C. neoformans var. gattii on 35 separate occasions, all from samples associated with E. camaldulensis. The global distribution of E. camaldulensis appears to correspond to the epidemiologic distribution of cryptococcosis caused by C. neoformans var. gattii. No other environmental source for the fungus has yet been detected, and no other eucalypt has the distribution pattern corresponding to reported cases caused by this fungus. These findings may provided an explanation for the high incidence of infections caused by C. neoformans var. gattii in Australian aborigines living in the Northern Territory and for its low worldwide incidence in acquired immunodeficiency syndrome patients.
Measurement of rotavirus-neutralizing coproantibody in children by fluorescent focus reduction assay
Authors: Coulson B S , Masendycz P J
Published: January 2020

A fluorescent focus reduction assay suitable for the measurement of rotavirus-neutralizing antibodies in the feces of children was developed. Of 408 stools tested, 7% showed false-positive neutralization, and the number of rotavirus serotypes neutralized by a fecal extract was proportional to the levels of antirotaviral immunoglobulin A in the extract.
Association of cell-adherent glycocalyx and endocarditis production by viridans group streptococci
Authors: Dall L H , Herndon B L
Published: January 2020

To assess the role of glycocalyx production in the pathogenesis of endocarditis caused by viridans group streptococci in adult patients, glycocalyx production was examined for 49 blood culture isolates. The tryptophan assay, a quantitative spectrophotometric test, was used to measure cell-adherent glycocalyx production. Absorbance values of the isolates that produced endocarditis were significantly higher (means, 0.166 versus 0.060 [P less than 0.001]). At a breakpoint of absorbance of 0.120, the sensitivity of the test was 0.83, the specificity was 0.96, and the predictive value was 0.95. These data suggest that the in vitro tryptophan assay of glycocalyx production by viridans group streptococci has potential value as a predictor of clinical pathogenicity.
Enhancement by calcium of the detection of cytomegalovirus in cells treated with dexamethasone and dimethyl sulfoxide
Authors: West P G , Baker W W
Published: January 2020

MRC-5 cultures treated with dexamethasone, dimethyl sulfoxide, and calcium were compared with untreated cultures and cultures treated with dexamethasone and dimethyl sulfoxide for the detection of human cytomegalovirus by the shell vial method. The addition of calcium resulted in significantly increased growth of human cytomegalovirus AD169. Protein studies and cell counts showed renewed cell proliferation in the treated cultures. When low-titer clinical specimens were retested, 27.5% of all positives revealed were found only on the vials treated with calcium. In a group of freshly tested specimens, the calcium-treated group accounted for 20% of the positives.
Antigenic relationships among the porin proteins of encapsulated Haemophilus influenzae clones
Authors: Martin D , Hamel J , Brodeur B R , Musser J M
Published: January 2020

Monoclonal antibodies (Mabs) specific for Haemophilus influenzae were generated to identify antigenic determinants shared among encapsulated H. influenzae clones. Sixteen MAbs reacted by Western immunoblot with a protein of an approximate molecular size of 40 kilodaltons corresponding to the P2 major outer membrane protein (porin). These MAbs also reacted with purified and recombinant H. influenzae porin. Fourteen of the MAbs recognized cell surface-exposed epitopes, and two of the MAbs, P2-16 and P2-17, identified epitopes that are not present or are not accessible on the cell surface. The reactivity spectrum of the MAb panel was studied by dot immunoassay against 32 serologically nontypeable and 119 encapsulated H. influenzae strains recovered worldwide, representing the major serotype a, b, and d clone families. MAbs P2-4 and P2-6 recognized only serotype b clones assigned to primary phylogenetic division I. These clones account for more than 99% of all invasive episodes worldwide. MAbs P2-3, P2-8, and P2-11 reacted with division I serotype b isolates and also identified all genetically allied strains expressing serotype a and d polysaccharide capsules. In contrast, none of the 16 MAbs reacted with genetically divergent serotype a or b clones assigned to primary phylogenetic division II. These results demonstrate that, in general, the patterns of P2 protein surface epitope exposure are cognate with genetic lineages of encapsulated H. influenzae strains and support the hypothesis that the population structure of encapsulated H. influenzae is predominantly clonal.
Detection of specific immunoglobulin E in patients with toxoplasmosis
Authors: Pinon J M , Toubas D , Marx C , Mougeot G , Bonnin A , Bonhomme A , Villaume M , Foudrinier F , Lepan H
Published: January 2020

An immunocapture assay was developed to detect Toxoplasma gondii-specific immunoglobulin E (IgE) in sera from adults with acute acquired infection or reactivation and from babies with congenital toxoplasmosis. The components of this assay were monoclonal antibody to human IgE, samples from patients, and T. gondii tachyzoites treated with Formalin. When T. gondii-specific IgE antibodies were present, visually detectable agglutination occurred. Sera, umbilical cord blood, fetal blood, cerebrospinal fluid, and amniotic fluid were tested by this method. Specific IgE antibodies were detected in sera from 25 (86%) of 29 adults who developed specific IgG antibody during pregnancy or had specific IgA and IgM antibodies. Specific IgE was present early during infection, at the time that IgM antibodies were present, and slightly preceding the presence of specific IgA antibodies. In 23 patients tested serially, IgE antibodies never persisted for longer than 4 months. No nonspecific anti-T. gondii IgE was detected in sera from uninfected individuals. Maternal IgE antibodies did not cross the placenta. In sera of patients with congenital toxoplasmosis, specific IgE antibodies were found at birth, during the first year of life, and during immunologic recrudescence following discontinuation of pyrimethamine-sulfonamide therapy. The IgE immunocapture assay is simple to perform. It is especially useful for determining when T. gondii was acquired by recently infected pregnant women.
Selective medium for isolation of Bacteroides gracilis
Authors: Lee K , Baron E J , Summanen P , Finegold S M
Published: January 2020

A new medium selective for Bacteroides gracilis was developed. The medium is tryptic soy agar (Difco Laboratories, Detroit, Mich.) containing nalidixic acid, teicoplanin, sodium formate, sodium fumarate, and potassium nitrate. All 18 strains of B. gracilis tested grew with only minimal inhibition. Most of the other 214 organisms tested, including most Bacteroides species, other anaerobes, and a substantial number of facultative anaerobes, were significantly inhibited by the medium. In a diagnostic study of 49 clinical specimens (28 patients with intra-abdominal infection, mostly gangrenous or perforated appendicitis), four strains of B. gracilis were isolated (from 4 different patients) on B. gracilis selective agar but were not detected on standard media.
Detection and identification of mycobacteria by amplification of rRNA
Authors: Böddinghaus B , Rogall T , Flohr T , Blöcker H , Böttger E C
Published: January 2020

Oligonucleotides specific at a genus, group, or species level were defined by a systematic comparison of small-subunit rRNA sequences from Mycobacterium tuberculosis, M. bovis, M. africanum, M. bovis BCG, M. avium, M. kansasii, M. marinum, M. gastri, M. chelonae, M. smegmatis, M. terrae, M. nonchromogenicum, M. xenopi, M. malmoense, M. szulgai, M. scrofulaceum, M. fortuitum, M. gordonae, M. intracellulare, M. simiae, M. flavescens, M. paratuberculosis, M. sphagni, M. cookii, M. komossense, M. phlei, and M. farcinica. On the basis of the defined oligonucleotides, the polymerase chain reaction technique was explored to develop a sensitive taxon-specific detection system for mycobacteria. By using M. tuberculosis as a model system, fewer than 10 bacteria could be reliably detected by this kind of assay. These results suggest that amplification of rRNA sequences by the polymerase chain reaction may provide a highly sensitive and specific tool for the direct detection of microorganisms without the need for prior cultivation.
Pneumocystis carinii karyotypes
Authors: Hong S T , Steele P E , Cushion M T , Walzer P D , Stringer S L , Stringer J R
Published: January 2020

Pulsed-field gel electrophoresis techniques were used to examine the chromosomes of Pneumocystis carinii isolated from laboratory rats and two human subjects. P. carinii organisms isolated from each of four rat colonies and from two patients each produced a distinct band pattern, but in all cases the bands ranged in size from 300 to 700 kilobase pairs. P. carinii from three rat colonies produced patterns containing 15 prominent bands. Of these 15 bands, 2 stained more intensely than would be expected of bands of their size, suggesting that the P. carinii haploid genome contains 17 to 19 chromosomes. Summing the molecular sizes of the bands and accounting for staining intensities suggested that the haploid genome of rat-derived P. carinii contains on the order of 10(7) base pairs. Human-derived P. carinii produced patterns containing 10 to 12 bands which appeared to be similar to the 15-band patterns seen in rat-derived P. carinii with respect to the size range of the bands. P. carinii from the fourth rat colony produced a more complex band pattern containing approximately 22 bands, most of which appeared to comigrate with the bands present in one of the 15-band P. carinii patterns, suggesting that these animals were simultaneously infected by two different varieties of P. carinii. Hybridization experiments using oligonucleotide probes specific for the P. carinii 18S rRNA gene supported this possibility. The band pattern of P. carinii derived from a given rat colony was generally stable over time. P. carinii band patterns were not strictly rat strain specific and appeared to be transferrable between animals housed in the same room.
Cytotoxin and enterotoxin production as factors delineating enteropathogenicity of Aeromonas caviae
Authors: Namdari H , Bottone E J
Published: January 2020

Twenty-one stool and environmental Aeromonas caviae isolates were studied for cytopathogenicity for cultured HEp-2 cells. Cytotoxic activity was demonstrated by the 21 A. caviae strains and by A. caviae ATCC 15468 after challenging HEp-2 cells with filtrates from a 24-h-old broth shake culture composed of double-strength, glucose-free Trypticase soy broth, incubated at 35 degrees C. Heat-stable cytotoxicity was observed 5 h after the addition of 1/5 and 1/10 concentrations of filtrates and consisted of cell rounding and cell detachment. Enterotoxin activity was also demonstrated through the suckling mouse assay. These data advance the role of A. caviae as a gastrointestinal pathogen.
Transient intestinal colonization by multiple phenotypes of Aeromonas species during the first week of life
Authors: Pazzaglia G , Escalante J R , Sack R B , Rocca C , Benavides V
Published: January 2020

The intestinal colonization rate of Aeromonas spp. was determined for 52 cesarean-born Peruvian neonates. Rectal swabs were obtained daily from newborns during their postdelivery hospitalization (mean = 5.5 days), and the gross appearances of their feces (blind determinations) were recorded. Aeromonas spp. were recovered from rectal swabs of 12 of 52 (23.1%) infants during their first week of life; the isolates were obtained from 5 of 9 (55.6%) infants with at least one stool with a watery consistency and from 7 of 43 (16.3%) neonates with no watery stools (P = 0.022). None of the infected infants became clinically ill. No other commonly recognized enteropathogens were detected in watery stools. An environmental survey indicated that hospital water was the probable source of infection. These and other data indicated that Aeromonas colonization occurs transiently at a very early age in Peruvian neonates and that in some instances, initial infection may be followed several days later by one or more watery stools of normal volume.
Comparison of human immune responses to purified Vero cell and human diploid cell rabies vaccines by using two different antibody titration methods
Authors: Kitala P M , Lindqvist K J , Koimett E , Johnson B K , Chunge C N , Perrin P , Olsvik O
Published: January 2020

Antibody responses to a conventional rabies preexposure regimen of a new purified Vero cell rabies vaccine (PVRV) and a human diploid cell vaccine (HDCV) were compared in 80 healthy Kenyan veterinary students. Forty-three of the students received the PVRV and 37 received the HDCV on days 0, 7, and 28. Antibody responses were monitored by using the rapid fluorescent-focus inhibition test (RFFIT) and an inhibition enzyme immunoassay (INH EIA) on days 0, 7, 28, and 49. Both vaccines elicited a rapid antibody response. A good correlation between the RFFIT titers and the INH EIA titers was obtained (r = 0.90). Our results also showed that the INH EIA was more reproducible and might therefore be a suitable substitute for the more expensive and less reproducible RFFIT. The geometric mean titers determined by both tests in the two groups of students were statistically similar during the test period. The RFFIT and the INH EIA gave comparable geometric mean titers, which differed significantly only on day 28 in the PVRV group. The effect of the new PVRV is comparable to that of the more expensive HDCV, as determined by the present test systems. The PVRV could therefore be the vaccine of choice, especially in tropical rabies-endemic areas, where the high cost of the HDCV has confined its use to a privileged few.
Multivariate analyses of cellular carbohydrates and fatty acids of Candida albicans, Torulopsis glabrata, and Saccharomyces cerevisiae
Authors: Brondz I , Olsen I
Published: January 2020

Quantitative data of major cellular carbohydrates distinguished Candida albicans or Torulopsis glabrata from Saccharomyces cerevisiae but not C. albicans from T. glabrata. Multivariate analyses of both carbohydrate and fatty acid variables (I. Brondz, I. Olsen, and M. Sjöström, J. Clin. Microbiol. 27:2815-2819, 1989), however, differentiated all three species.
Comparison of epidemic and endemic group G streptococci by restriction enzyme analysis
Authors: Martin N J , Kaplan E L , Gerber M A , Menegus M A , Randolph M , Bell K , Cleary P P
Published: January 2020

Restriction enzyme profiles of group G beta-hemolytic streptococci associated with a point source outbreak and an outbreak of sporadic pharyngitis in two different communities were compared. To asses the epidemiologic utility of this approach for studying group G streptococci, DNA fingerprints of strains responsible for a point source outbreak of pharyngitis associated with the consumption of contaminated food were compared with DNA fingerprints of pharyngeal isolates from children with pharyngitis seen at a pediatric practice during a 6-month period. In each epidemiologic situation, a single strain characterized by a unique restriction enzyme pattern predominated. The results are compatible with the conclusion that human infections could be limited to a few strains of group G streptococci which have the capacity to spread through a given population. The restriction enzyme profiles proved to be a highly specific and precise means of evaluating strain relatedness and of providing further understanding of the epidemiology of group G streptococcal infections.
Homotypic serum antibody responses to rotavirus proteins following primary infection of young children with serotype 1 rotavirus
Authors: Richardson S C , Bishop R F
Published: January 2020

The class-specific antibody responses to serotype 1 rotavirus structural proteins were examined by immunoblotting with sera obtained from young children hospitalized with acute rotavirus diarrhea caused by serotype 1. All were believed to be primary infections. Three consecutive samples were obtained from 16 patients during the acute and convalescent phases of the disease and then approximately 4 months later. Immunoglobulin G (IgG)-class antibody responses to two inner capsid proteins (VP2 and VP6) and to the major homologous outer capsid protein (VP7) were detected in all patients. Antibody responses to VP6 were rapid, increased in intensity during 20 to 40 days after the onset of symptoms, and persisted for more than 4 months. Responses to VP2 and VP7 were more delayed, were maximal in convalescent-phase sera, and decreased markedly in intensity 4 months after the onset of symptoms in the majority of children. Two patients with evidence of mixed infection showed persisting high levels of antibody to VP7. Responses to the outer capsid protein VP4 were detected in 67% of patients, peaked at 20 to 40 days after the onset of symptoms, and were no longer detected at 4 months in the majority of patients. It is likely that the immunoblotting technique underestimated responses to VP4. Acute- and convalescent-phase sera (known to contain antirotavirus IgM or IgA measured by enzyme immunoassay) were also examined by immunoblotting. IgM- and IgA-class antibody responses to viral proteins VP2, VP4, and VP7 appeared to be qualitatively identical to those observed for IgG in the same serum samples.
Antibody response of Schistosoma mansoni-infected human subjects to the recombinant P28 glutathione-S-transferase and to synthetic peptides
Authors: Auriault C , Gras-Masse H , Pierce R J , Butterworth A E , Wolowczuk I , Capron M , Ouma J H , Balloul J M , Khalife J , Neyrinck J L
Published: January 2020

The 28-kilodalton antigen of Schistosoma mansoni has been previously described as having importance as the basis for a potential vaccine. The P28 recombinant molecule and three peptides derived from its primary sequence, namely the 24-43, 115-131, and 140-153 peptides, have been tested to evaluate the humoral responses of Kenyan school children previously classified as susceptible or resistant to reinfection after chemotherapy. We report here that the P28 molecule and two of the peptides studied (peptides 115-131 and 140-153) can be used for detecting specific immunoglobulin G (IgG), IgE, and IgA antibodies. Moreover, the IgG4 response of the susceptible population was significantly greater than that of the resistant group, whereas no differences between the two populations were noticed in total IgG anti-P28 antibodies. This suggested that IgG4 could play a role in the lack of immunity of susceptible patients. A strong IgG3 response restricted to the 140-153 peptide was observed but did not discriminate between the resistant and susceptible populations. In contrast, a marked increase in the IgA response to the 140-153 peptide epitope(s) in sera of the resistant population was noticed. Taken together, these results suggest that the P28 antigen and two of the three peptides selected could give predictive information about the development of the disease or the efficiency of vaccination with P28 as the immunogen.
Differential agglutination test for diagnosis of recently acquired infection with Toxoplasma gondii
Authors: Dannemann B R , Vaughan W C , Thulliez P , Remington J S
Published: January 2020

We evaluated the recently described differential agglutination test (HS/AC test) to differentiate recently acquired toxoplasma infections from those acquired in the more distant past in sera obtained from 38 patients with carefully defined symptomatic and asymptomatic infections. AC antigens detect acute-phase-specific immunoglobulin G (IgG) antibodies against Toxoplasma gondii tachyzoites that are formed only during the acute stage of infection in humans. The HS/AC test correctly identified recently acquired infections in patients with toxoplasmic lymphadenopathy or asymptomatic infections (including infections in 7 women who seroconverted during gestation) in 31 of 33 patients. We also studied 15 individuals who had been infected for at least 2 years. In that group, only 13% had an acute pattern in the HS/AC test. However, the wide range in times from infection (from 2 to 14 years) did not allow for an estimate of when the pattern in the HS/AC test changed from acute to not acute. These results reveal that in the appropriate clinical situation, when both IgG and IgM tests are positive and a question still remains about the acuteness of infection, the HS/AC test may be useful for differentiating between toxoplasma infections acquired recently and those acquired in the more distant past.
Oerskovia xanthineolytica implicated in peritonitis associated with peritoneal dialysis: case report and review of Oerskovia infections in humans
Authors: Rihs J D , McNeil M M , Brown J M , Yu V L
Published: January 2020

Oerskovia species are nocardialike bacteria that have been implicated as pathogens only rarely. These organisms are branched, gram-positive bacilli that are oxidase negative, catalase positive, and non-acid fast. Unlike Nocardia species, these organisms are motile, do not produce aerial mycelia, and possess a cell wall with large amounts of galactose. Colonies are bright yellow and produce branched vegetative hyphae on nutrient agar. A 70-year-old patient undergoing chronic ambulatory peritoneal dialysis for end-stage renal dysfunction developed recurrent peritonitis. Five peritoneal fluid cultures and one catheter specimen obtained over a period of two weeks yielded a gram-positive bacillus; Oerskovia xanthineolytica was isolated from all six cultures. Prolonged systemic therapy with gentamicin and vancomycin was unsuccessful in curing the peritonitis, but the infection resolved following removal of the peritoneal catheter. This is the first reported case of peritonitis associated with this microorganism. A review of previously described Oerskovia infections, most of which were associated with foreign bodies, showed that removal of infected foci was usually necessary for cure.
Comparison of immunofluorescence, particle agglutination, and enzyme immunoassays for detection of human T-cell leukemia virus type I antibody in African sera
Authors: Verdier M , Denis F , Leonard G , Sangare A , Patillaud S , Prince-David M , Essex M
Published: January 2020

The effectiveness of four screening tests for detecting antibody to human T-cell leukemia virus type I (HTLV-I) was determined by using 2,700 African serum specimens. The tests studied were indirect immunofluorescence, particle agglutination from Fujirebio, and two enzyme immunoassays, one from Abbott Laboratories that used virus lysate from HUT 102 cells and the other from Cambridge BioScience Corp. that used an env recombinant protein. Positive and doubtful sera were confirmed by Western immunoblot and radioimmunoprecipitation assay with Food and Drug Administration seropositivity criteria. The best results were obtained with the two enzyme immunoassays, which were more sensitive (100 and 98.6% [Abbott and Cambridge, respectively]) and more specific (98.7 and 96.5%). Indirect immunofluorescence exhibited difficulties for reading and interpretation. With particle agglutination, prozone was observed for 9 of 78 HTLV-I-positive serum specimens. False-positives in any of the tests were not linked to cross-reactions with human immunodeficiency viruses. However, confirmation tests remain necessary for HTLV-I screening.
Adhesive fimbriae associated with porcine enterotoxigenic Escherichia coli of the O141 serotype
Authors: Kennan R M , Monckton R P
Published: January 2020

Enterotoxigenic Escherichia coli of the O141 serotype, isolated from piglets with postweaning coliform enteritis but producing none of the characterized adhesive fimbriae, was examined for fimbrial production by transmission electron microscopy. Two strains that produced numerous fimbriae were chosen for further characterization. The fimbriae were isolated and purified and had a subunit molecular weight of 17,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Using antiserum raised against this protein, we have shown it to be specific for the 17,000-molecular-weight band by immunoblotting and to be directed against the fimbriae by immunoelectron microscopy. These fimbriae were not produced when the bacteria were grown at 18 degrees C and did not show any mannose-resistant hemagglutination of the erythrocytes tested. We propose that these are a new type of adhesive fimbriae associated with porcine enterotoxigenic E. coli of the O141 serotype.
Epidemiologic study of Taylorella equigenitalis strains by field inversion gel electrophoresis of genomic restriction endonuclease fragments
Authors: Bleumink-Pluym N , ter Laak E A , van der Zeijst B A
Published: January 2020

Contagious equine metritis (CEM), a sexually transmitted bacterial disease, was first described in thoroughbred horses. It also occurs in nonthoroughbred horses, in which it produces isolated, apparently unrelated outbreaks. Thirty-two strains of Taylorella equigenitalis, the causative agent of CEM, from all over the world were characterized by field inversion gel electrophoresis of fragments of genomic DNA obtained by digestion with low-cleavage-frequency restriction enzymes. This resulted in a division into five clearly distinct groups. Strains from thoroughbred horses from all continents belonged to one group. Strains from nonthoroughbred horses from various countries were different from strains from thoroughbred horses; four groups could be determined. Two groups contained both streptomycin-resistant and streptomycin-susceptible strains. The data indicate that CEM in nonthoroughbreds did not originate from the thoroughbred population; also, the reverse was not demonstrated. Thus, extensive international transportation directives regarding the testing of nonthoroughbred horses for CEM may need reconsideration.
New sensitive and specific assay for human immunodeficiency virus antibodies using labeled recombinant fusion protein and time-resolved fluoroimmunoassay
Authors: Siitari H , Turunen P , Schrimsher J , Nunn M
Published: January 2020

A new, rapid method for the detection of human immunodeficiency virus type 1 (HIV-1) antibody by time-resolved fluoroimmunoassay (TR-FIA) was developed. In this assay format, microtitration strips were coated with a recombinant fusion protein, and the same protein was labeled with europium and added into the wells simultaneously with the test specimens. The recombinant fusion protein contained the HIV-1 p24 gag protein sequence that carried an insertion, near the carboxyl terminus, of a 23-amino-acid sequence from a highly conserved region of the HIV-1 gp41 envelope protein. This recombinant antigen enabled the detection of antibodies to both gag and env gene products. When this assay was compared with a commercially available recombinant enzyme-linked immunoabsorbent assay (ELISA) by using four quality-control panels, the TR-FIA detected all 20 positive specimens, while the recombinant ELISA detected only 16 of them. This increased sensitivity could be demonstrated directly by the assay of dilution series of HIV-1-positive sera. The analysis of two seroconversion panels by TR-FIA and six ELISAs showed that TR-FIA allowed detection of antibody in infected individuals 16 days earlier than the other assays did. In addition to being highly sensitive, the assay was highly specific; of the 57 samples shown to be repeatedly positive by ELISA but known to be HIV-1 negative by Western immunoblot analysis, only 1 sample reacted positively in this assay. The specificity of the assay was 99.9% when 1.054 random serum specimens were tested.
Comparison of Western immunoblot antigens and interpretive criteria for detection of antibody to human T-lymphotropic virus types I and II
Authors: Gallo D , Diggs J L , Hanson C V
Published: January 2020

Twenty human T-lymphotropic virus type I (HTLV-I) antibody-positive sera from Japan, Hawaii, and the Marshall Islands and 15 HTLV type II (HTLV-II) antibody-positive sera from intravenous drug users in the United States were tested by immunoblotting with two recombinant HTLV-I proteins and three commercial kits to determine whether there were any differences in reactions between HTLV-I- and HTLV-II-positive sera by the Western immunoblot method and, also, to evaluate the ability of these reagents to detect HTLV-I- and HTLV-II-seropositive individuals by using the recommended Western blot interpretation. These sera were first extensively characterized by immunofluorescence, enzyme immunoassay, radioimmunoprecipitation assay, and Western blot using HTLV-I and HTLV-II viral lysates and an envelope (env) recombinant protein. Although both HTLV-I- and HTLV-II antibody-positive sera reacted with the env protein gp68, reactions with the gp46 env antigens appeared to be specific for HTLV-I. It was found that the use of either p19 or p24 core bands plus an env reaction instead of only the p24 plus env reaction (as presently recommended) increased the number of positive interpretations for HTLV-I but had no effect on the number of HTLV-II-positive interpretations.
DNA probes for the identification of Nocardia asteroides
Authors: Brownell G H , Belcher K E
Published: January 2020

DNA probes for the rapid identification of Nocardia asteroides were obtained by constructing a genomic library of strain GUH-2 in the lambda cloning vector EMBL3. Of 50 recombinant clones tested, 2 were identified that hybridized with 31% of the N. asteroides strains in a reference collection without cross-hybridization with related members of the Actinomycetales. Additional libraries were then generated from selected strains of N. asteroides that had failed to hybridize with any of the GUH-2 clones. Four additional clones were obtained from these strains which, when pooled, provided DNA probes specific for all of the N. asteroides strains tested.
Rapid detection of cytomegalovirus DNA in urine samples with a dot blot hybridization immunoenzymatic assay
Authors: Musiani M , Zerbini M , Gentilomi G , Gallinella G , Venturoli S , Gibellini D , La Placa M
Published: January 2020

A dot blot hybridization immunoenzymatic assay for the rapid detection of cytomegalovirus DNA in urine samples was developed by using a digoxigenin-labeled probe which was immunoenzymatically visualized by antidigoxigenin Fab fragments labeled with alkaline phosphatase. A total of 516 urine samples from different groups of subjects were analyzed, and the hybridization assay was able to yield results within 24 h. The results obtained were compared with results for detection of cytomegalovirus antigens in infected cell cultures.
Arylsulfatase activity for differentiating Mycobacterium avium and Mycobacterium intracellulare
Authors: Tomioka H , Saito H , Sato K , Dawson D J
Published: January 2020

Arylsulfatase activities (96-h reaction) of various strains of Mycobacterium avium and M. intracellulare, as identified by a DNA probe test, were measured. The enzyme activities of M. avium strains were significantly lower [corrected] than those of M. intracellulare strains (P less than 0.005 to P less than 0.025). The enzyme activities did not vary with serovar; that is, the activities of serovars 1, 2, 8, and 9 (belonging to M. avium) were similar to each other, as were the activities of serovars 7, 12, 13, 14, and 16 (belonging to M. intracellulare). The results indicate the usefulness of the arylsulfatase test in distinguishing M. avium from M. intracellulare in an accurate manner.
Detection of herpes simplex virus by the Kodak SureCell Herpes Test
Authors: Dorian K J , Beatty E , Atterbury K E
Published: January 2020

The Kodak SureCell Herpes Test Kit (SC-HSV) was evaluated in a high-risk sexually transmitted disease clinic population. A total of 97 lesion specimens (from 94 patients) were tested for the presence of herpes simplex virus by SC-HSV and by spin-amplified tissue culture confirmed by an enzyme immunoassay. The overall sensitivity of SC-HSV compared with that of spin-amplified tissue culture-enzyme immunoassay was 81.1%; the specificity was 100%. For vesicular lesions only, SC-HSV sensitivity was 100%; for nonvesicular lesions, sensitivity was 75.6%, SC-HSV was rapid (less than 15 min) and very easy to perform.
Meningitis in a neonate caused by Leuconostoc sp
Authors: Friedland I R , Snipelisky M , Khoosal M
Published: January 2020

A case of meningitis in a neonate caused by vancomycin-resistant Leuconostoc mesenteroides is presented. This case was complicated by severe ventriculitis and was ultimately fatal. Infection with Leuconostoc spp. is rare but should be suspected when vancomycin-resistant organisms resembling streptococci are isolated. Previous reports of this infection are reviewed.
False-positive latex agglutination test for Neisseria meningitidis groups A and Y caused by povidone-iodine antiseptic contamination of cerebrospinal fluid
Authors: D'Amato R F , Hochstein L , Fay E A
Published: January 2020

The cerebrospinal fluid of a patient yielded a positive latex agglutination test for Neisseria meningitidis groups A and Y. The latex agglutination results were not consistent with clinical and other laboratory findings. An investigation determined that the positive agglutination test was caused by contamination of the cerebrospinal fluid with povidone-iodine during the lumbar puncture.
Molecular epidemiology of Shigella infections: plasmid profiles, serotype correlation, and restriction endonuclease analysis
Authors: Litwin C M , Storm A L , Chipowsky S , Ryan K J
Published: January 2020

Plasmid isolation was used to refine the epidemiologic analysis for 168 shigellosis cases in Pima County, Ariz. Plasmids of less than 20 kb were used for comparison of plasmid profiles. Plasmid patterns for each species were distinct. A total of 57 of 74 (77%) Shigella flexneri strains could be placed into seven plasmid patterns, 70 of 79 (89%) Shigella sonnei strains could be placed into seven patterns, 12 Shigella boydii strains could be placed into six patterns, and each of 3 Shigella dysenteriae strains differed. There was a correlation between plasmid patterns and serotypes for S. flexneri, and multiple plasmid patterns were found in serotypes 1, 2, and 6, offering a refinement beyond serotyping. In previous studies we found an association between Mexican travel and an S. sonnei 5.1-kb plasmid. When this plasmid was used as a probe, strong homology was seen with numerous small plasmids in all Shigella species: restriction endonuclease analysis revealed a 1.1-kb AvaI-AvaII fragment common to various plasmids of S. sonnei. S. flexneri, and S. boydii independent of species. Of 34 Pima County Shigella isolates from the mid-1970s. 8 showed plasmid patterns similar to those of the recent isolates. Some plasmids from S. sonnei, S. flexneri, and S. boydii strains isolated in the 1970s also contained the AvaI-AvaII fragment. The conservation of this specific fragment in our population for more than 12 years suggests that it may contain genes important in virulence or survival.
Nosocomial transmission of respiratory syncytial virus in immunocompromised adults
Authors: Englund J A , Anderson L J , Rhame F S
Published: January 2020

Respiratory syncytial virus (RSV) isolates obtained from nine infected immunocompromised adult patients hospitalized during two consecutive winters (January through April 1987 and 1988) were collected and analyzed against a panel of monoclonal antibodies by an enzyme immunoassay. The history of the patients' illness, onset of symptoms, and date of initial isolation of virus was correlated with the hospital ward and time of hospitalization. Three patients died of respiratory failure related to RSV infection acquired nosocomially. A cluster of RSV disease in four patients hospitalized simultaneously during the 1987 season was demonstrated to be caused by four antigenically distinct viruses; despite an epidemiologic link among the patients, each had been infected from a different source. The RSV disease in the five immunocompromised adults in 1988 was caused by two distinct strains; three patients were infected with RSV subgroup A/4, and two were infected with RSV subgroup B/2. Combining the epidemiologic and strain characterization studies, none of four patients in 1987 were infected from each other, and two of five patients in 1988 may have been infected, directly or indirectly, from one of the other five. The strain characterization studies demonstrated the potential complexity of RSV nosocomial transmission and the need to consider a number of sources for transmission in developing effective prevention strategies. The three deaths underscore the importance of nosocomial RSV disease and the importance of effective prevention strategies.