bluuebunny/crossref_metadata_2025 huggingface dataset:
Microneutralization test for influenza A and B and parainfluenza 1 and 2 viruses that uses continuous cell lines and fresh serum enhancement
Authors: Frank A L , Puck J , Hughes B J , Cate T R
Published: January 2020

A modified microneutralization test for influenza A and B and parainfluenza 1 and 2 viruses was developed. Use of continuous cell lines (Madin-Darby canine kidney and LLC-MK2), hemagglutination for virus detection, and transfer plates and other microtiter equipment resulted in a highly mechanized technique suitable for titrating large numbers of sera easily and relatively inexpensively. Titers of heat-inactivated human sera were enhanced 0.5 to 3.5 log2 by addition of fresh hamster or human serum to the test. Seroconversion rates and identification of seronegative persons were not changed by fresh serum enhancement, but the magnitude of seroconversion was often increased and the distribution of positive titers was broadened. For influenza A and B, seroconversion rates in the microneutralization test were equivalent to those obtained in rhesus monkey kidney tube neutralization tests. For influenza B, seroconversion rates by micro-neutralization were almost double those obtained with the hemagglutination inhibition test, but the rates were similar for influenza A/USSR (H1N1). Preexisting microneutralization titers correlated well with resistance of infection with influenza B. Limited experience with parainfluenza 1 and 2 was similar to previously reported findings with the tube neutralization test.
Rapid, quantitative, semiautomated assay for virus-induced and immune human interferons
Authors: Green J A , Yeh T J , Overall J C
Published: January 2020

An improved human interferon (IF) assay is described. This procedure is based on the ability of encephalomyocarditis virus to replicate in WISH cell microcultures with the production of discrete plaques in the presence of a liquid tissue culture medium. Performance of 50% plaque reduction endpoint assays in micro-culture required only 0.1 ml of specimen for determinations using duplicate dilutions beginning at 1:3. Semiautomated equipment facilitated simultaneous in situ dilution and distribution of multiple IF samples in cultures containing preformed WISH cell monolayers. An incubation period of 5 to 6 h was adequate for development of maximal antiviral activity by both virus- and immune-induced IF. Sensitivity of the encephalomyocarditis microplaque reduction assay was comparable to that of other commonly used techniques. The method is rapid, can be completed within 30 h from the beginning of the IF assay, and is able to accommodate as many as 40 to 50 samples at a single time. Encephalomyocarditis microplaque reduction is suitable for the quantitation of IF as an antiviral agent or a lymphokine.
Immunological nonidentity of Pseudomonas paucimobilis with Pseudomonas aeruginosa and Pseudomonas cepacia
Authors: Smalley D L , Ourth D D
Published: January 2020

This investigation determined the serum agglutination activity and serum bactericidal response after rabbit immunization with Pseudomonas paucimobilis. Agglutination activity of antisera showed a twofold increase in titer from before immunization to 4 weeks post-immunization and peaked at 8 weeks post-immunization with a titer of 1:512. 2-Mercaptoethanol reduction of immunoglobulin M decreased agglutination titers. No major antigens were found to be common from crude antigen preparations of P. paucimobilis, Pseudomonas aeruginosa and Pseudomonas cepacia when tested with antisera to P. paucimobilis. Serum bactericidal activity was found in post-immunization antisera at 8 and 12 weeks against P. paucimobilis, with no activity present before immunization or at 4 weeks post-immunization. Antisera against P. paucimobilis showed no bactericidal activity against P. aeruginosa or P. cepacia.
Enriched brucella medium for storage and transport of cultures of Campylobacter fetus subsp. jejuni
Authors: Wang W L , Luechtefeld N W , Reller L B , Blaser M J
Published: January 2020

A semisolid brucella medium with 10% sheep blood was used for storage and transport of Campylobacter fetus subsp. jejuni and subsp. intestinalis and kept isolated alive about 3 weeks or longer at 25 degrees C or when sent through the regular mail.
Influence of residual moisture and sealing atmosphere on viability of two freeze-dried viral vaccines
Authors: Precausta P M , Simatos D , Le Pemp M , Devaux B , Kato F
Published: January 2020

This study demonstrated the complexity of the factors leading to changes in the infectivity titers of freeze-dried canine distemper and poultry infectious bronchitis viral vaccines. The change in moisture content during the storage period was an additional parameter which may influence the infectivity titer. The results emphasized the difficulty of predetermining variations in infectivity titers from the initial residual moisture. The analysis of the variations in infectivity titers during the storage of two vaccines led to the formulation of a hypothesis of the presence of two components of different thermostability. Moreover, the temporary increase in the infectivity titer of infectious bronchitis vaccine stored progressively dissociating during storage concurrent with a progressive inactivation of infectious particles.
Campylobacter fetus subsp. jejuni as a cause of gastroenteritis in Jakarta, Indonesia
Authors: Ringertz S , Rockhill R C , Ringertz O , Sutomo A
Published: January 2020

Campylobacter fetus subsp. jejuni was isolated from the feces of 15 out of 144 (10%) children (0 to 9 years old) and 4 out of 251 (2%) adults with gastroenteritis and was found together with another enteric pathogen in 2 of the children and in all 4 adults. It was isolated from 2 out of 7 (28%) children and 3 out of 160 (2%) adults with suspected typhoid fever. The bacterium was recovered from 3 out of 4 orphanage children with diarrhea and from 1 without symptoms and was isolated from only 1 child in a control group of 221 persons.
False no-growth blood cultures in pneumococcal pneumonia
Authors: Adeniyi-Jones C C , Stevens D L , Rasquinha E S
Published: January 2020

The growth of Streptococcus pneumoniae in commercial media containing 14C-labeled substrates was studied experimentally; the results of blood cultures that were positive for S. pneumoniae over a 14-month period were analyzed to explain no-growth but radiometrically positive blood cultures from four patients with clinically diagnosed pneumococcal pneumonia. The growth of S. pneumonoiae in aerobic blood culture vials resulted in a chocolate color in the medium. S. pneumoniae grew rapidly in both aerobic and anaerobic media, but 14CO2 evolved from the metabolism of the labeled substrates was detected only in the aerobic culture vials. Radiometric detection lagged behind growth of the organisms and was accompanied by visual changes in the media. By 24 h, the viability of the culture was on the decline; radiometric readings remained positive even when the culture had died.
An unusual phagocytosis: ingestion of a Giardia lamblia cyst by an Entamoeba coli trophozoite
Authors: Logan A L , Turner W E , Price J
Published: January 2020

Microscopic examination of a permanently stained fecal preparation revealed the unusual inclusion of a Giardia lamblia cyst within the cytoplasm of an Entamoeba coli trophozoite.
Relationship to coagglutination of immunoglobulin class dissociated from Escherichia coli-antibody complexes
Authors: Hovanec D L , Absolom D R , van Oss C J , Gorzynski E A
Published: January 2020

Immunoglobulin G was present only in those Escherichia coli antisera causing coagglutination, as determined by immunoelectrophoretic patterns in eluates of antigen-antibody complexes.
Isolation of oxidase-negative Pseudomonas aeruginosa from urine culture
Authors: McCleskey F K , Adams E D
Published: January 2020

An isolate of Pseudomonas aeruginosa lacking characteristic indophenol oxidase was recovered from a catheterized urine specimen.
Euparal as a permanent mounting medium for helminth eggs and proglottids
Authors: Berlin O G , Miller M J
Published: January 2020

The importance of euparal as a permanent mounting medium for eggs of parasites and the process of making permanent slides are analyzed and discussed in detail. Studies show that helminth eggs mounted in euparal exhibit excellent optical and drying properties. Euparal also can be used to identify proglottids of Taenia species and to examine for the presence of Trichinella spiralis in suspicious muscle biopsies.
Legionella gormanii
sp. nov
Authors: Morris George K. , Steigerwalt Arnold , Feeley James C. , Wong Edward S. , Martin William T. , Patton Charlotte M. , Brenner Don J.
Published: January 2020

A new species of
Legionella
was isolated from soil collected from a creek bank. The name
Legionella gormanii
sp. nov. is proposed.
Detection of enterotoxigenic Escherichia coli colonization factor antigen I in stool specimens by an enzyme-linked immunosorbent assay
Authors: Evans D G , Evans D J , Clegg S
Published: January 2020

An enzyme-linked immunosorbent assay (ELISA) was employed to detect and quantitate the fimbrial colonization factor antigen (CFA/I) of enterotoxigenic Escherichia coli in stool specimens obtained from adult cases of diarrhea in which CFA/I-positive E. coli was the known causative agent. The inhibition method, or blocking technique, was used. In this method, a standardized dilution of human anti-CFA/I serum was preincubated with dilutions of stool extract before transfer to CFA/I-coated microtiter plate wells, and then ELISA was performed with alkaline phosphatase-conjugated anti-human immunoglobulin. CFA/I purified from E. coli strain H-10407 (O78:H11) was used. Acute-phase diarrheal stool specimens were found to contain approximately 3.0 mg of antigen (mean value) per g stool, whereas control (CFA/I-negative) specimens contained insignificant amounts (less than 0.03 mg/g) of antigen. Also, CFA/I was detected in culture fluids of CFA/I positive enterotoxigenic E. coli belonging to a variety of serotypes and was undetectable in similar preparations from P-strains (spontaneous CFA/I-negative derivatives) of the same test cultures. Equivalent results were obtained in ELISA tests by using bacterial cells taken from isolated colonies grown on CFA agar. These results indicate that the ELISA technique will be useful for the diagnosis of diarrhea caused by CFA/I-positive enterotoxigenic E. coli.
Evaluation of preservation methods and solid media suitable for recovery of Ureaplasma urealyticum from transported urine specimens
Authors: Hipp S S , Rockwood L D , Gaafar H A , Han Y
Published: January 2020

Urine specimens to be tested for Ureaplasma urealyticum (T-strain mycoplasma) must often be transported to a central laboratory for identification. To examine survival of these organisms over 2 days of transport, fresh urine samples were tested for the presence of ureaplasmas and then divided into four groups: (i) fresh, (ii) frozen, (iii) preserved with 1% (wt/vol) boric acid at room temperature, and (iv) preserved with 10% dimethyl sulfoxide and frozen. The samples were cultured on both A7 and New York City solid media, and the estimates of survival were compared to that of fresh urine. Less than 10% survival of Ureaplasma was observed in 11 of 14 specimens stored frozen for 2 days without preservation; six specimens lost all organisms. Specimens containing either dimethyl sulfoxide or boric acid showed higher survival rates, although neither method consistently approached the full recovery of the T-strains found with the fresh urine. Ureaplasmas from fresh specimens grew well on both New York City and A7 media; however, the New York City medium proved superior for those preserved with boric acid and for urine samples containing few ureaplasmas. These results indicate that preservation of samples does increase the yield of U. urealyticum from urine samples delayed in transit.
Rapid detection of Gram-negative bacteriuria by Limulus amoebocyte lysate assay
Authors: Nachum R , Shanbrom E
Published: January 2020

The Limulus amoebocyte lysate (LAL) test was evaluated for rapid detection of gram-negative bacteriuria in an adult patient population. Time to gelation of a standard LAL preparation was used as a measure of significant (greater than 10(5) bacteria per ml) gram-negative bacteriuria, and the results of 190 LAL assays were compared with quantitative urine cultures. Initially, 33 of 36 urine specimens containing greater than 10(5) gram-negative bacteria per ml were detected by LAL assay. The three false-negative LAL tests were the result of urine pH levels below the pH minimum for LAL gelation; neutralization of these urine specimens resulted in positive LAL assays and 100% correlation with culture results. All 36 bacteriuric urine specimens were LAL positive within 15 min, with the majority of assays (86.1%) being positive after only 10 min of incubation at 37 degrees C. These data compared favorably with gelation times of 15 min when 1 X 10(5) to 2 X 10(5) gram-negative bacteria per ml were added to sterile urine. Two urine samples obtained from male patients with culture-proven gonococcal urethritis yielded positive LAL assays. The LAL assay was shown to correctly differentiate 96.2% of urine specimens as containing less than 10(5) or greater than 10(5) gram-negative bacteria per ml. The results of this study have shown that the LAL test can be used as a rapid, simple, and reliable screening procedure for the diagnosis of clinically significant gram-negative bacteriuria.
Hemolysin and K antigens in relation to serotype and hemagglutination type of Escherichia coli isolated from extraintestinal infections
Authors: Evans D J , Evans D G , Höhne C , Noble M A , Haldane E V , Lior H , Young L S
Published: January 2020

Escherichia coli isolated from cases of bacteremia and from a variety of urinary tract infections were characterized according to serotype (O:H antigenicity), K type (possession of K1, K2, K3, K12, or K13), hemagglutination (HA) type, and production of beta-hemolysin. Results obtained with the bacteremia and urinary tract infection isolates were similar except for more hemolytic isolated from urine than from blood (42 versus 29%) and more K1+ isolates from blood than from urine (50 versus 29%). A close correlation was found between Ha type VI (production of fimbriae which mediate mannose-resistant HA of human and African green monkey erythrocytes) and the production of hemolysin or K1 capsular antigen or both. Most (95 of 98, or 95%) of the HA type VI+ blood isolates and most (146 of 164, or 89%) of the HA type VI+ urine isolates produced hemolysin or K1 or both, in contrast to 22 and 26%, respectively, of those belonging to HA types other than HA type VI. Also, 76% of all hemolytic and 70% of all K1+ isolates belonged to HA type VI. Remarkably few of the HA type VI+ isolates (13%) and even fewer of the HA type VI- isolates (3%) produced both K1 and hemolysin; these belonged mainly to serotypes O16:H6, O18:H7 and O2:H4. Other major serogroups were usually K1+/hemolysin- (O1, O7) or K1-/hemolysin+ (O2, O4, O6). At least 74% (262 of 351) and possibly as many as 83% (293 of 351) of those isolates which produced mannose-resistant HA of human erythrocytes were classified as HA type VI+; 31 isolates produced mannose-resistant HA with all erythrocytes tested. Taking serogroup and serotype into consideration, we conclude that the E. coli fimbrial hemagglutinin(s) responsible for the HA type VI phenotype will prove to be the same as the virulence-associated mannose-resistant adhesins of uropathogenic E. coli which other investigators have characterized as unique fimbrial antigens detectable by mannose-resistant HA of human erythrocytes.
Diagnostic characters of an atypical Candida
Authors: Baker J G , Salkin I F , Pincus D H , D'Amato R F
Published: January 2020

The morphological and physiological characters of an atypical Candida isolated from diverse clinical specimens are described. The colony and microscopic morphologies of the atypical Candida most closely resemble those of Candida tropicalis or of reported sucrose-negative variants of C. tropicalis. However, the atypical isolates differ from C. tropicalis by their inability to ferment sucrose or melezitose and from the sucrose-negative variants by their inability to assimilate inulin and their varied utilization of other carbon substrates.
Enzyme immunoassay for detection of antibody-coated bacteria
Authors: Stamm W E , Cutter B E , Grootes-Reuvecamp G A
Published: January 2020

To quantitatively evaluate factors potentially affecting antibody coating of bacteria in urine, we developed an assay with enzyme-linked rather than fluorescein-conjugated immunoglobulin. Using the enzyme immunoassay (EIA) in an in vitro system in which concentrations of serotype O44 Escherichia coli and antibody titer to E. coli Orr O44 O antigen were known, we compared specimens run in parallel with a fluorescent antibody (FA) assay. At greater than or equal to 10(5) bacteria per ml, antibody titer to homologous O antigen correlated directly with absorbance in the EIA. Both tests had sensitivities exceeding 95% in specimens containing greater than or equal to 10(5) bacteria per ml, but the FA test detected 23 of 27 positive specimens with less than 10(5) bacteria per ml compared with 21 of 43 detected by EIA (P = 0.002). However, nonspecific fluorescence caused false positives in 8% of negative tests run by FA compared with 1% of simultaneous EIA tests (P = 0.05). pH alterations and pretreatment of bacteria with antibiotics did not affect either test. Heterologous E. coli strains showed no cross-reactivity with O44 antiserum, but all Staphylococcus aureus isolates tested caused false positives in both assays, and one Klebsiella strain repeatedly caused a false-positive FA assay. The EIA appears to be a simple, quantitative, and specific technique for detection of antibody-coated bacteria in this experimental system.
Ether treatment of type B influenza virus antigen for the hemagglutination inhibition test
Authors: Monto A S , Maassab H F
Published: January 2020

Ether treatment was studied as a method of increasing the ability of type B influenza antigen to detect antibody by hemagglutination inhibition. Comparisons were made with the untreated antigen, with an eluate made from the same virus, and with a standard type B antigen of an earlier virus. Results were evaluated based on the comparative ability to detect rises in antibody titer, as well as the relative frequency of antibody prevalence determined by each method. The ether-treated antigen was far superior to the untreated antigen in both respects; it was also superior to the eluate, although the difference was less pronounced. The treated antigen performed better than the standard type B antigen in detecting antibody in children, but there was little difference in adults. This pattern was felt to be a result of the closer relation of the treated antigen to the infecting strain. The method is, therefore, proposed as a means of producing more reactive antigens of currently circulating strains of type B influenza virus.
Molecular epidemiology of human rotaviruses in Melbourne, Australia, from 1973 to 1979, as determined by electrophoresis of genome ribonucleic acid
Authors: Rodger S M , Bishop R F , Birch C , McLean B , Holmes I H
Published: January 2020

Rotaviruses contain a double-stranded ribonucleic acid genome consisting of 11 segments. Gel electrophoresis separates genome segments and allows identification of strain differences. This electrophoretic typing technique was applied to rotavirus specimens from 116 children and 72 newborn babies. Between 1973 and 1979, 17 different electropherotypes of rotavirus were observed in children with acute gastroenteritis. These electropherotypes showed a sequential pattern of appearance, with a limited number of electropherotypes present at any given time. By contrast, only two electropherotypes were identified from isolates from newborn babies in seven hospitals during 1975 to 1979. These two electropherotypes were very similar and were never identified in children with acute gastroenteritis. One of the neonatal electropherotypes was found in the nurseries of five different hospitals and persisted in one hospital for 4 years. Electrophoretic typing techniques can be applied routinely and reproducibly to small samples of feces and could prove to be of value in epidemiological studies of rotavirus infection
Direct enzyme-linked immunosorbent assay that uses peroxidase-labeled antigen for determination of immunoglobulin M antibody to cytomegalovirus
Authors: van Loon A M , Heessen F W , van der Logt J T , van der Veen J
Published: January 2020

A direct enzyme-linked immunosorbent assay was developed for the measurement of immunoglobulin M (IgM) antibody to cytomegalovirus (CMV). Wells of microtiter plates were coated with anti-human IgM. Each patient's serum was added at a dilution of 1:100, and IgM from the serum was allowed to react with anti-human IgM. The amount of CMV-specific IgM antibody bound was determined by measuring the intensity of color change after the addition of peroxidase-labeled CMV antigen and substrate. Nuclei of infected cells served as an antigen source. CMV IgM could be detected only in IgM fractions of sera from patients with a recent CMV infection. Rheumatoid factor did not cause false-positive results. No cross-reactions were observed when paired sera from 22 patients with herpes simplex or varicella and single sera from 12 patients with suspected infectious mononucleosis were tested by the direct enzyme-linked immunosorbent assay. Each of 17 patients with a seroconversion for CMV antibody showed CMV-specific IgM antibody. In six of these patients the antibody was detected in the initial serum. The direct enzyme-linked immunosorbent assay for CMV IgM is a specific and sensitive test for the diagnosis of recent CMV infections and possesses distinct advantages over indirect tests.
Diagnosis of bacteremia in children by quantitative direct plating and a radiometric procedure
Authors: La Scolea L J , Dryja D , Sullivan T D , Mosovich L , Ellerstein N , Neter E
Published: January 2020

During a 1-year period, three bacteriological systems for detecting bacteremia in children were analyzed, namely, the BACTEC system (Johnston Laboratories, Inc., Cockeysville, Md.), the Fisher/Lederle bottle (Lederle Diagnostics, Pearl River, N.Y.), and a direct plating method of blood termed quantitative direct plating (QDP). Of 2,123 blood cultures, 135 (6.4%) were positive; Haemophilus influenzae type b, Neisseria meningitidis, and Streptococcus pneumoniae accounted for 3.4%, representing 61 patients, other pathogens accounted for 0.6%, and contaminants accounted for 2.4%. Of 72 cultures yielding H. influenzae, N. meningitidis, and S. pneumoniae, 60 were recovered by both broth systems, 2 by BACTEC only and 10 by Fisher/Lederle bottle only. The BACTEC system failed to register a positive growth index reading by 24 h in 15 cultures which were positive for H. influenzae, even though growth had occurred, as shown by positive subculture and microscopy at this time. QDP detected 89% of the cultures positive for H. influenzae and N. meningitidis, of which 55% yielded results before either broth procedure. Only 50% of the cultures positive for S. pneumoniae yielded growth on QDP. This difference in the recovery rate probably is accounted for by the number of organisms in the blood. Thus, more than 100 organisms per ml of blood were found in 71% of cultures positive for H. influenzae and N. meningitidis but in only 7% of those positive for S. pneumoniae. These studies, then, have revealed that H. influenzae, which grew well in BACTEC broth, did not, however, give a significant growth index reading during day 1 of incubation, in contrast to N. meningitidis and S. pneumoniae. The QDP system not only provided information on the magnitude of bacteremia due to H. influenzae and N. meningitidis but frequently allowed earlier diagnosis and, thus, proved to be a valuable, simple, and inexpensive supplementary technique for broth cultures, although not for the diagnosis of S. pneumoniae bacteremia.
Clinical laboratory evaluation of the Auto-Microbic system for rapid identification of Enterobacteriaceae
Authors: Hasyn J J , Cundy K R , Dietz C C , Wong W
Published: January 2020

The capability of the Auto-Microbic system (Vitek Systems, Inc., Hazelwood, Mo.) has been expanded to identify members of the family Enterobacteriaceae with the use of a sealed, disposable accessory card (the Enterobacteriaceae Biochemical Card) containing 26 biochemical tests. To judge the accuracy of the AutoMicrobic system's identification in a hospital laboratory, 933 Enterobacteriaceae isolates were studied. The AutoMicrobic system provided the correct identification for 905 of the isolates (97%). For Enterobacteriaceae excluding Escherichia coli (533 isolates not E. coli), 506 isolates were correctly identified (94.9%). The AutoMicrobic system integrates well into the clinical microbiology laboratory, providing a simple, accurate, and efficient automated system for the rapid identification of Enterobacteriaceae.
Comparative evaluation of the Iatron serological Candida check kit and the API 20C kit for identification of medically important Candida species
Authors: Shinoda T , Kaufman L , Padhye A A
Published: January 2020

A newly developed commercial serological test (Iatron Laboratories, Inc., Tokyo, Japan) for the rapid identification of medically important species of Candida was evaluated against the API 20C (Analytab Products, Plainview, N.Y.) and the standard Wickerham assimilation and fermentation procedures. Our results indicated that the Iatron and the API 20C methods are 95% accurate since both permitted identification of 78 of 82 Candida isolates, representing eight medically important species. None of the tests on nine Cryptococcus, six Trichosporon, three Geotrichum, three Saccharomyces, and one Rhodotorula species yielded false-positive reactions. False-positive serological tests occurred with a species of Pichia and Candida rugosa. The API 20C procedure correctly identified C. rugosa but not the Pichia sp. The Iatron method permitted reliable identification of the Candida species in 10 min to 5 h, whereas the API 20C procedure required 48 to 72 h. Neither method could properly identify sucrose-negative Candida tropicalis or Candida lusitaniae isolates. In addition, Candida albicans isolates could be serotyped by the Iatron method.
Transferable urease activity in Providencia stuartii
Authors: Grant R B , Penner J L , Hennessy J N , Jackowski B J
Published: January 2020

Six urea-positive Providencia stuartii strains were tested for transmissible urease determinants. Two strains, when implanted with "helper" conjugative plasmids, were found to be capable of transferring urease genes to Escherichia coli or urea-negative P. stuartii. Recombination of the urease genes with the helper plasmid in P. stuartii was noted in one case. One of the urea-positive P. staurtii strains was found to harbor a conjugative plasmid which mediated both urease activity and ampicillin resistance. This large plasmid (molecular weight, approximately 140 x 10(6)) was transmissible to and stably maintained in E. coli strains. The demonstration of transmissible genes for urease activity in P. stuartii is significant in that it accounts for previous problems associated with classifying urea-positive strains of this species.
Rapid diagnostic test that uses isocitrate lyase activity for identification of Yersinia pestis
Authors: Hillier S L , Charnetzky W T
Published: January 2020

The presence of high levels of isocitrate lyase activity in Yersinia pestis grown on blood agar base medium, as compared with low levels of this enzyme in Yersinia pseudotuberculosis and Yersinia enterocolitica, suggested that the differences in the levels of this enzyme could be used for the presumptive identification of Y. pestis. A modified, semiquantitative assay for isocitrate lyase activity is described which requires no expensive instrumentation, utilizes readily available chemicals and substrates, and requires only 20 min for completion. This test yielded positive results with all 108 isolates of Y. pestis tested and negative results with all strains of Y. pseudotuberculosis (68 isolates) and Y. enterocolitica (202 isolates) tested. Less than 2% of the approximately 1,300 non-Yersinia isolates from the family Enterobacteriaceae and none of the 93 isolates from the family Pseudomonadaceae yielded positive results. We conclude that this test provides for rapid identification of Y. pestis and should be useful in the initial screening of isolates from rodent and flea populations and in the presumptive identification of this organism from suspected cases of human plague.
Minimum number of bacteria needed for antigen detection by counterimmunoelectrophoresis: in vivo and in vitro studies
Authors: Fung J C , Wicher K
Published: January 2020

Threshold concentrations of Streptococcus pneumoniae type 3, Haemophilus influenzae type b, and Streptococcus sp. group B type Ib required for positive counterimmunoelectrophoresis reactions were determined in vivo and in vitro. Animals were infected intraperitoneally with various concentrations of microorganisms: adult mice with S. pneumoniae, suckling rats with H. influenzae, and 3-week-old mice with Streptococcus sp. group B. At 24 h after infection a minimum blood concentration of 10(3) colony-forming units (CFU)/ml was needed for S. pneumoniae or H. influenzae before antigen was detected in the serum. A minimum concentration of 10(6) CFU/ml was needed for Streptococcus sp. group B at 10 h after infection. Larger threshold concentrations (10(4) CFU/ml for S. pneumoniae, 10(5) CFU/ml for H. influenzae, and 10(7) CFU/ml for Streptococcus) were required in broth-grown cultures before cell-free antigens could be demonstrated by counterimmunoelectrophoresis in the medium. Marked levels of antigen release by group B streptococci were observed as the cultures entered early stationary phase. This study provides evidence of a long-accepted, though poorly substantiated, hypothesis that a threshold concentration of microorganism is necessary before counterimmunoelectrophoresis reactions become positive. Counterimmunoelecrophoresis results for clinical specimens should be interpreted cautiously in light of this evidence.
Sensitivity, specificity, and predictive value of anti-candida serum precipitin and agglutinin quantification: comparison of counterimmunoelectrophoresis and latex agglutination
Authors: Dee T H , Johnson G M , Berger C S
Published: January 2020

Many serological techniques have been developed to aid in the discrimination of significant candidiasis from other clinical states. Serum anti-candida precipitin and agglutinin quantification by counterimmunoelectrophoresis and latex agglutination were statistically evaluated as to their respective ability to accomplish this discrimination. Forty-five serum specimens from 16 patients with documented disease and 2 with presumptive disease and 81 specimens from 70 control patients were studied. The control population consisted of patients with candida colonization, transient candidemia, bacteremia, other systemic mycoses, and healthy medical personnel. The two techniques were compared as to sensitivity, specificity, and predictive value of a positive and a negative test. Using a precipitin or agglutinin titer of greater than or equal to 1:8 as the criterion for a positive test, we obtained the following results: counterimmunoelectrophoresis, 78, 97, 88, and 94%, respectively; latex agglutination, 94, 50, 33, and 97%, respectively.
Pseudomonas pickettii
Bacteremia
Authors: Fujita S. , Yoshida T. , Matsubara F.
Published: January 2020

A case of bacteremia caused by
Pseudomonas pickettii
is reported. This represents the first case of infection due to this species.
Rapid bead counting and dispensing device for radioimmunoassays and enzyme-linked immunosorbent assays
Authors: Hui G W
Published: January 2020

A simple time- and labor-saving device is described for counting and dispensing beads used in solid-phase radioimmunoassay and enzyme-linked immunosorbent assay. In parallel radioimmunoassays, the data obtained with beads prepared by this device indicate an equivalent or superior sensitivity as compared with beads handled in the more tedious, conventional manner. The rapid handling of beads not only facilitates the processing of larger numbers of specimens, but also has the advantage of exposing up to 60 beads simultaneously to reactants in the same reaction tray.
Rapid Flagella Stain
Authors: Forbes Lorenzo
Published: January 2020

Leifson stain was modified to produce rapid staining of bacterial flagella on untreated microscope slides. The procedure was reliable when tested against a variety of motile and nonmotile bacteria.
Metabolic analysis of serologically defined Neisseria meningitidis isolates by frequency-pulsed electron capture gas-liquid chromatography
Authors: Brooks J B , Kellogg D S , Shepherd M E , Craven D E
Published: January 2020

Eight serogroups [A, B, C, D, X, Y, 29E [Z'], and W135] along with nongroupable and nontypable strains of Neisseria meningitidis were cultured in a defined liquid medium. The whole-culture spent medium was extracted, derivatized, and analyzed by frequency-pulsed electron capture gas-liquid chromatography. The frequency-pulsed electron capture gas-liquid chromatography profiles were then used to group the organisms on the basis of their metabolic profiles. First, two basic groups were formed which consisted of elevated spent-medium compounds and reduced spent-medium compounds. Then, these two basic groups were further subdivided on the basis of metabolites and cellular fatty acids detected in the spent medium to form a total of seven metabolic groups. The nongroupable strains (with the exception of two strains) fell within one of these metabolic groups. The elevated spent-medium compounds group contained all of the A, B, Y, and Z' strains, and the reduced spent-medium compounds group contained most of the C and all of the W135 and D strains. The potential usefulness of the metabolic group scheme is discussed.
Comparison of hemagglutination inhibition test and enzyme-linked immunosorbent assay for determining antibody to rubella virus
Authors: Shekarchi I C , Sever J L , Tzan N , Ley A , Ward L C , Madden D
Published: January 2020

The hemagglutination inhibition test (HAI) and the enzyme-linked immunosorbent assay (ELISA) for detecting antibody to rubella virus were compared by testing 25 sets of paired sera taken before and after infection and 10 sets of sera taken during acute and convalescent stages of the disease and by screening 700 serum samples from the Collaborative Perinatal Project, NIH/NINCDS. The tests were found to be comparable in their ability to detect positive and negative sera, rises in titers, and seroconversions. When a purified antigen and carefully prepared reagents were used, ELISA was found to be as accurate and reliable as HAI. ELISA required no pretreatment of serum, could easily be automated, and was less time-consuming than HAI.
Ankylosing spondylitis associated with Trichomonas vaginalis infection
Authors: Kuberski T T
Published: January 2020

A patient is described who developed signs and symptoms of ankylosing spondylitis after prostatitis due to Trichomonas vaginalis. Chronic prostatitis of unknown cause had previously been reported as being common in patients with ankylosing spondylitis. The observations in this case raise the possibility that T. vaginalis might play a role in the prostatitis and pathogenesis of ankylosing spondylitis in some patients.
Evaluation of techniques for isolation of group A streptococci from throat cultures
Authors: Kurzynski T A , Van Holten C M
Published: January 2020

In the first study, selective sulfamethoxazole-trimethoprim blood agar (SXT-BA) and conventional blood agar (BA) plates incubated under CO2 and anaerobically were compared for their ability to recover group A streptococci from throat cultures. Recovery rates were: SXT-BA (anaerobic), 100%; SXT-BA (CO2), 98%; BA (anaerobic), 89.2%; and BA (CO2), 76.5%. Primary plate bacitracin test results could be read on significantly more of the SXT-BA plates. Readability rates were: SXT-BA (anaerobic), 97%; SXT-BA (CO2), 96%; BA (anaerobic), 70.6%; and BA (CO2), 32.4%. A second study compared with the SXT-BA method versus a BA-double-disk (BA-DD) method which utilizes conventional media with addition of a bacitracin differentiation and a sulfamethoxazole-trimethoprim susceptibility disk placed adjacent to one another in the heavy area of inoculation. Isolation rates were: SXT-BA, 100% and BA-DD, 88%. Readability rates for direct bacitracin tests were: SXT-BA, 92% and BA-DD, 76.2%. In our hands, the SXT-BA method was superior for yielding highest isolation rates and for yielding highest readability rates of direct bacitracin test results.
Sensitivity of Toxorhynchites amboinensis mosquitoes versus chicken embryonic cell cultures for assays of Venezuelan encephalitis virus
Authors: Scherer W F , Chin J
Published: January 2020

Toxorhynchites amboinensis mosquitoes inoculated intrathoracically with Venezuelan encephalitis virus and tested for infectious virus 12 to 19 days later by inoculation of primary chicken embryonic cell cultures yielded approximately the same titers of virus as did direct inoculation of cultures, with counting of plaques 3 days thereafter. Titers were slightly higher in T. amboinensis for three virus strains, equal for two virus strains, and slightly lower for two virus strains. Comparative titers of four strains were similar, whether virus suspensions came from infectious vertebrate cells or infected invertebrate (T. amboinensis) cells. Each of the seven strains of Venezuelan encephalitis virus reached virus concentrations of 10(4.2) to 10(5.1) plaque-forming units in individual T. amboinensis mosquitoes after extrinsic incubation periods of 12 to 19 days. No temperature-sensitive (29 versus 37 degrees C) virus was detected in T. amboinensis mosquitoes infected by six strains of Venezuelan encephalitis virus.
New method that uses binding of immunoglobulin A to group A streptococcal immunoglobulin A Fc receptors for demonstration of microbial immunoglobulin A protease activity
Authors: Lindahl L , Schalén C , Christensen P
Published: January 2020

A new method is described for the detection of bacterial immunoglobulin A (IgA) protease which splits IgA into Fab and Fc fragments. The method takes advantage of a recent finding that receptors for IgA fragments occur commonly among type 4 group A streptococci. The bacterial preparation to be tested for protease activity was first incubated with radiolabeled purified IgA1 myeloma protein, and the proportion of radioactivity bound to a standard suspension of the streptococci was then measured. Since isolated Fab fragments do not bind to streptococcal IgA receptors, a decrease in the amount of radioactivity bound to the streptococci, as compared with the amount before digestion, indicates the presence of protease in the test preparation. Using this method, protease activity was detected in Neisseria gonorrhoeae, Neisseria meningitidis, Haemophilus influenzae, Streptococcus pneumoniae, and Streptococcus sanguis, but not in Escherichia coli or Branhamella catarrhalis.
Improved method for trypsin digestion of Paraplast sections before immunofluorescence staining
Authors: Rowse-Eagle D , Watson H D , Tignor G H
Published: January 2020

Formalin-fixed, Paraplast-embedded tissue sections mounted on subbed slides were digested with crude trypsin in modified Sorensen phosphate buffer containing sodium fluoride before immunofluorescence staining. This method prevented detachment of sections from slides during processing, thereby permitting immunofluorescence and histological examinations of adjacent serial sections.
Combined Modified Heat-Stable Acid Phosphatase and 68°C Catalase Test for Differentiation of Mycobacteria
Authors: Tierno Philip M. , Milstoc Mayer
Published: January 2020

A rapid, simple, modified heat-stable acid phosphatase and 68°C catalase test for the differentiation of mycobacteria is described. A total of 181 strains of mycobacteria, including 141 slow growers and 40 rapid growers, were investigated for acid phosphatase and catalase activities.
Evaluation of an indirect hemagglutination test for Legionella pneumophila serogroups 1 to 4
Authors: Yonke C A , Stiefel H E , Wilson D L , Wentworth B B
Published: January 2020

Parallel testing of 895 sera by indirect hemagglutination and indirect fluorescent-antibody techniques showed 97.3% agreement. Although the indirect hemagglutination technique usually showed more cross-reactivity among serogroups than the indirect fluorescent-antibody technique with Formalin-fixed antigens and a conjugate which detected primarily immunoglobulin G antibodies, heterologous serogroup reactions were significantly lower than homologous serogroup titers and the etiological serogroup could be easily defined. The indirect hemagglutination techniques showed no cross-reactivity with a crude extract of Escherichia coli O13:K92:H4. Since the indirect hemagglutination technique was shown to detect both immunoglobulin M and immunoglobulin G antibodies and was found to be rapid, simple, and inexpensive, it appears to be an excellent alternative to the indirect fluorescent-antibody test for serodiagnosis of legionellosis.
Antibodies to the enterobacterial common antigen: standardization of the passive hemagglutination test and levels in normal human sera
Authors: Malkamäki M
Published: January 2020

The passive hemagglutination test for antibodies against the enterobacterial common antigen (ECA) of Kunin was standardized for diagnostic purposes. Human erythrocytes were coated with a soluble ECA+ preparation from Salmonella typhimurium or, as specificity controls, with a similar ECA- preparation from congenic ECA-negative bacteria with saline, and the hemagglutination assay was performed on microtiter plates. The specificity of the test was ascertained further by inhibition assays with purified ECA and with crude ECA+ and ECA- preparations. The reproducibility of the tests was 96.4%; on this basis, a fourfold or larger difference in titers was regarded as significant. The anti-ECA titers in 649 serum samples from healthy persons ranged from less than 4 to 8,192. The titers increased with age, so that th geometric mean titers were 57 at 1.5 years of age and 201 at 45 years of age. After this, the titers decreased again, to a low of 52 in persons more than 70 years old. Women had higher titers than men up to the age of 40 years.
Seroreactivity to Mycoplasma pneumoniae and Legionella pneumophila: lack of a statistically significant relationship
Authors: Renner E D , Helms C M , Hall N H , Johnson W , Wong Y W , Lattimer G L
Published: January 2020

We reviewed antibody titers to Mycoplasma pneumoniae and Legionella pneumophila serogroup I in sera from 1,060 cases of acute respiratory infection to determine whether there was an association in seroreactivity to these organisms. Of the 170 serum pairs with antibodies to L. pneumophila (35 seroconversions and 135 with presumptive titers), 32 (18.8%) demonstrated seroreactivity to M. pneumoniae (17 seroconversions and 15 with presumptive titers). This frequency was not significantly greater than the seroreactivity to M. pneumoniae observed in sera without antibodies to L. pneumophila (17.5%) (0.05 less than P less than 0.10), which included 111 seroconversions and 45 sera with presumptive titers.
Delayed hypersensitivity to heart antigens in Chagas' disease as measured by in vitro lymphocyte stimulation
Authors: Mosca W , Plaja J
Published: January 2020

Reactivity to Trypanosoma cruzi antigens and autoreactivity to heart antigens were evaluated in 27 patients with Chagasic cardiomyopathy (group I), 52 patients without evidence of cardiac dysfunction (group II), and 36 selected controls, either healthy patients or patients with other heart diseases (group III). The in vitro lymphoblastogenesis response to T. cruzi antigens was found to be high in groups I and II and low in group III. The mean stimulation index to T. cruzi antigens, in fact, tended to be highest in group I, suggesting a more intense immune response in patients with Chagasic cardiomyopathy. The proportion of individuals with reactivity to heart antigens was 28.6% in group I, 25% in group II, and 0% in group III. The finding of an equal percentage of reactivity to heart antigens in groups I and II was unexpected, as a higher incidence of positive reactions in group I was predicted. Consequently, it is thought that this finding and its relevance to the pathogenic process of Chagasic cardiomyopathy need to be carefully assessed in a longitudinal study.
Diarrhea due to Cryptosporidium infection in artificially reared lambs
Authors: Tzipori S , Angus K W , Campbell I , Clerihew L W
Published: January 2020

Severe diarrhea which lasted 7 to 12 days occurred in 40 of 48 artificially reared lambs within 5 to 12 days of birth, and 16 of them died. Of 16 diarrheic fecal samples examined, 10 contained Cryptosporidium oocysts and 1 contained rotavirus, but no other known enteropathogen was detected. Upon histological examination, cryptosporidia were found in the ilea of three affected lambs, and in one of them, villous atrophy and fusion, with epithelial cross-bridging between villi, were present in distal small intestine. Diarrhea was induced in two specific pathogen-free lambs by oral inoculation with fecal homogenate containing Cryptosporidium oocysts. Both the small and large intestines became infected with the organism, and associated lesions included stunting, fusion, and deformities of villi in the distal small intestine, with replacement of columnar enterocytes by immature cuboidal cells. Subclinical infections were induced in newborn specific pathogen-free mice and rats. Judged by these data, the lamb-derived Cryptosporidium sp. is similar to those recovered from calves, deer, and humans.
Bacteriocins as tools in analysis of nosocomial Klebsiella pneumoniae infections
Authors: Bauernfeind A , Petermüller C , Schneider R
Published: January 2020

Epidemiological analysis of isolates from nosocomial infections caused by Klebsiella pneumoniae was improved by the use of bacteriocins in addition to capsular serotyping. Screening for bacteriocins produced by 77 reference strains for capsular serotyping identified 39 strains, and 8 of these strains were selected as a typing set. Using this set, we found that 241 to 259 (91%) nonepidemic clinical isolates of K. pneumoniae were inhibited by one or more of the eight producers. Of the most frequent bacteriocin type there were 31 examples (12%). High reproducibility of typing patterns (83.3%) and easy practicability of typing were achieved with a streak-and-point method avoiding the use of suspensions of bacteriocins and the risk of instability. The Klebsiella bacteriocins were active also on Enterobacter and Shigella species and on Escherichia coli strains, but were ineffective on other Enterobacteriacae.
Characterization of some groups of gram-negative nonfermentative bacteria by the carbon source alkalinization technique
Authors: Martin R , Riley P S , Hollis D G , Weaver R E , Krichevsky M I
Published: January 2020

A total of 541 gram-negative nonfermentative bacterial strains comprising 26 species and unclassified groups were characterized by routine diagnostic and carbon substrate alkalinization techniques. These microorganisms were tested for the ability to cause alkalinization of a basal medium on a total of 217 substrates. We found that 58 carbon substrates had some discriminatory potential. We also performed 30 routine diagnostic tests. The results of these studies were evaluated by numerical taxonomy techniques. A cluster analysis of the results by the Jaccard coefficient method identified 30 clusters at the 45% level. We identified 39 tests that separated most of the groups. Groups of similar organisms or organisms that were difficult to identify were analyzed, and tests that were differential were identified. Because of variability within the clusters, further studies utilizing deoxyribonucleic acid-deoxyribonucleic acid homologies should be undertaken.