bluuebunny/crossref_metadata_2025 huggingface dataset:
Enzyme-linked protein A: an enzyme-linked immunosorbent assay reagent for detection of human immunoglobulin G and virus-specific antibody
Authors: Madore H P , Baumgarten A
Published: January 2020

A general-purpose reagent capable of reacting with immunoglobulin G in a modified enzyme-linked immunosorbent assay technique was prepared by using protein A coupled with horseradish peroxidase. The reagent detected low levels (0.003 to 1.0 microgram/ml) of human immunoglobulin G and was also applied in an enzyme-linked immunosorbent assay for titration of antibody to human cytomegalovirus. The antibody titers to human cytomegalovirus determined by enzyme-linked immunosorbent assay and by complement fixation were compared. The correlation coefficient between the two techniques was 0.85, but the enzyme-linked immunosorbent assay was 10 times more sensitive than complement fixation in terms of antibody titers detected.
Immunoglobulin A Antibodies Reactive with
Streptococcus mutans
in Saliva of Adults, Children, and Predentate Infants
Authors: Bammann L. L. , Gibbons R. J.
Published: January 2020

Immunoglobulin A (IgA) antibodies reactive with
Streptococcus mutans
MT3 cells (serotype
c
) were sought, using an indirect enzyme-linked immunosorbent assay, in the saliva of humans who either harbored or did not harbor detectable levels of this organism. Samples of unstimulated whole saliva from three adults and one child who were infected with
S. mutans
contained IgA which bound to MT3 cells. Saliva samples of two adults studied also contained IgA which reacted with
S. mutans
strains of serotypes
e, g, a,
and
b
, the latter two of which are rarely isolated from humans. The saliva of three children who did not harbor detectable levels of
S. mutans
and of three of five predentate infants also contained IgA reactive with MT3 cells. The latter observation is of special interest since
S. mutans
does not colonize the mouth before eruption of teeth. Thus, the presence of salivary IgA reactive with
S. mutans
cells is not necessarily related to present or past infection by this organism. Absorption with MT3 cells markedly reduced the reactivity of adult saliva without greatly altering the total concentration of IgA present; this suggests that the IgA was not binding to
S. mutans
MT3 cells via Fc receptors. The possibility that the antibodies which reacted with
S. mutans
MT3 may have been induced to other bacteria with cross-reactive antigens was supported by the finding that absorption of saliva with mixed bacterial growth derived from common dairy products significantly reduced its reactivity. Absorption experiments further suggested that a significant portion of the salivary IgA antibodies was binding to glucans on the cell surface.
Detection, identification, and comparison of Capnocytophaga, Bacteroides ochraceus, and DF-1
Authors: Newman M G , Sutter V L , Pickett M J , Blachman U , Greenwood J R , Grinenko V , Citron D
Published: January 2020

Working independently, three laboratories had recognized considerable similarity among certain strains of dysgonic, fermentative, capnophilic, surface translocating, gram-negative bacilli referred to as Capnocytophaga, Bacteroides ochraceus, and Center for Disease Control biogroup DF-1. To determine the relationship among these groups, 21 strains were exchanged and independently characterized by the three laboratories. Additionally, a fourth laboratory examined the deoxyribonucleic acid homologies of the same strains. Using methods common to dental microbiology, eight of the strains had been isolated from the gingival sulcus and periodontal lesions and identified as Capnocytophaga. Three strains isolated from blood and transtracheal aspirate had been characterized by conventional anaerobic methods and recorded as B. ochraceus. Ten strains isolated from sputum, blood, throat, spinal fluid, and tracheal aspirate had been identified as DF-1 with the methods of E. O. King and a buffered single-substrate technique. All strains were similar in respect to colonial and microscopic morphology, surface translocation, biochemical features, gas-liquid chromatograms of metabolic end products, and deoxyribonucleic acid composition. We conclude that these biogroups should be termed Capnocytophaga species.
Adhesion to a human cell line by Escherichia coli strains isolated during urinary tract infections
Authors: Chabanon G , Hartley C L , Richmond M H
Published: January 2020

It has been shown that some, but not all, Escherichia coli strains isolated from urine adhere, in vitro, to the surface of uroepithelial or vaginal cells. In the present study, 212 strains, isolated from urine of 212 infected patients, were tested for adhesion by using an in vitro human cell line assay. A variable degree of attachment to the cell monolayer was detected in these strains. From patients with cystitis, only 19 (9.7%) of the 195 strains examined were adherent, whereas 5 (29.4%) of the 17 pyelonephritis strains had similar properties (P less than 0.05). To investigate the incidence of adhesion in the clinical manifestations of urinary tract infection, a sample of patients was picked at random from those with cystitis. During cystitis caused by adhesive bacteria, patients suffer more often from macroscopic hematuria than from dysuria, frequency, or recurrency (P less than 0.05). This study shows that E. coli strains isolated from urine samples possess a strikingly difference in capacity to adhere to a human cell line surface as demonstrated previously with uroepithelial or vaginal cells. Moreover, according to these data, the adhesion of E. coli may be considered as a virulent factor and would play a part in the infection of the urinary tract in humans.
Acceptability and cost savings of selective sputum microbiology in a community teaching hospital
Authors: Heineman H S , Radano R R
Published: January 2020

Our experience in introducing selective sputum microbiology into a clinical laboratory was recorded prospectively and analyzed. Based on low-power microscopy with determination of ratios of polymorphonuclear to squamous cells, 32% of specimens were discarded as unfit for culture. Speedy processing and prompt telephone calls afforded opportunities to replace these with better specimens, but only 29% of rejected specimens were resubmitted. Interpretive readings of smears for microorganisms yielded meaningful yielded meaningful information to clinicians and correctly predicted culture results in 73.8% of acceptable specimens. Technological time was similar to that required to process the same number of specimens in the usual way, but rejection of unsatisfactory specimens led to a 22% saving in supplies. Clinicians readily accepted the new system. Where nurses are responsible for specimen collection, they must be informed of the rationale for selective culture and the unreliability of gross visual inspection in evaluating sputum.
Enteric adenoviruses: detection, replication, and significance
Authors: Retter M , Middleton P J , Tam J S , Petric M
Published: January 2020

Adenoviruses can be demonstrated readily in the stools of pediatric gastroenteritis patients by electron microscopy or counterimmunoelectrophoresis, but in 45% of these cases the virus will not grow in cell culture. Indirect immunofluorescence microscopy can be used to detect nongrowing strains of adenovirus; these strains have a unique single-cell fluorescence pattern. Hematoxylin and eosin staining reveals adenovirus-like inclusion bodies in the same distribution as fluorescent cells. Pretreatment of nongrowing adenovirus with convalescent-phase patient serum neutralized its ability to infect the cell culture and produce fluorescent cells. Indirect immunofluorescence microscopy compared favorably with electron microscopy in demonstrating virus in the stools of patients.
Detection of antibodies to alphaviruses by enzyme-linked immunosorbent assay
Authors: Frazier C L , Shope R E
Published: January 2020

Cell culture-derived antigens detected antibodies to alphaviruses in human sera with the enzyme-linked immunosorbent assay technique. Results correlated with those from hemagglutination inhibition and neutralization tests.
Plate Assay for Detection of
Leptospira interrogans
serovar
pomona
Hemolysin
Authors: Stamm Lola V. , Charon Nyles W.
Published: January 2020

A plate assay which utilizes the addition of a blood agar overlay for detection of hemolysin by colonies of
Leptospira interrogans
serovar
pomona
is described.
Enzyme-linked immunosorbent assay for detection of antibodies to murine hepatitis virus
Authors: Peters R L , Collins M J , O'Beirne A J , Howton P A , Hourihan S L , Thomas S F
Published: January 2020

An enzyme-linked immunosorbent assay was developed for the detection of antibodies to murine hepatitis virus. A high prevalence of antibody to murine hepatitis virus was found by the enzyme-linked immunosorbent assay in colonies with a low prevalence of complement-fixing antibodies. Murine hepatitis virus strain A59 was found to be broadly reactive as an enzyme-linked immunosorbent assay antigen.
Isolation of acid-fast organisms from surgical specimens
Authors: Morimoto M G , Rothrock A G , Stottmeier K D
Published: January 2020

A total of 204 surgical specimens positive for acid-fast organisms yielded 169 strains of Mycobacterium tuberculosis, 15 of which were isolated by Middlebrook 7H-9 broth medium only. Mycobacteria other than M. tuberculosis were isolated from 33 specimens, and Nocardia asteroides was isolated from 2 specimens.
Survival of Ureaplasma urealyticum on different kinds of swabs
Authors: Poulin S A , Kundsin R B , Horne H W
Published: January 2020

The survival of Ureaplasma urealyticum on five different types of swabs routinely used for obtaining clinical specimens is limited to 1 h. Wooden applicator sticks inhibit the alkaline color change in broth and result in a significant loss of isolates if broth alone is used.
Simian rotavirus SA-11 plaque formation in the presence of trypsin
Authors: Ramia S , Sattar S A
Published: January 2020

Incorporation of 5 micrograms of trpsin per ml of the overlay (Eagle minimal essential medium-0.7% Ionagar no. 2) was found to be necessary for plaque formation by simian rotavirus SA-11. Plaques of 3 to 4 mm in diameter were produced in MA-104 cells after 5 days of incubation at 37 degrees C. Plaque size was even larger (5 to 6 mm) in monolayers of African green monkey kidney cells. Addition of diethyl-aminotheyl-dextran, protamine sulfate, or 5-bromodeoxyuridine to the trypsin-containing overlay did not improve plaque formation by the virus. Incorporation of beef extract or yeast extract to a final concentration of 0.5% in the trypsin-containing overlay inhibited plaque formation. On the other hand, the presence of lactalbumin hydrolysate or peptone at a similar concentration in the overlay did not inhibit plaque formation. When methylcellulose was used instead of the agar as the solidifying agent in the overlay, no plaques were seen. SA-11 is a useful model for the study of human rotaviruses, and this relatively simple plaque assay system should further enhance its usefulness in this regard.
Enzyme-linked immunosorbent assay for serology of infectious bovine rhinotracheitis virus infections
Authors: Payment P , Assaf R , Trudel M , Marois P
Published: January 2020

An enzyme-linked immunosorbent assay was developed to detect antibodies to infectious bovine rhinotracheitis virus in bovine sera. The test used viral antigen purified in a sucrose density gradient, and the antibody titers detected were up to 100 times higher than those seen in the serum neutralization test. When 250 sera were tested by those two tests, 146 were positive and 49 were negative in both tests. Only 1 serum was negative in the immunoassay test and positive in the neutralization test. However, 54 sera negative in the neutralization test were positive in the immunoassay test. These positive results appear to be in agreement with the increased sensitivity of the enzyme immunoassay.
Evaluation of commercial latex agglutination reagents for grouping streptococci
Authors: Facklam R R , Cooksey R C , Wortham E C
Published: January 2020

A total of 155 strains of beta-hemolytic streptococci were serologically grouped by conventional techniques (Lancefield extraction and capillary precipitin testing) and by latex agglutination (LA). Agreement between conventional and LA techniques was 97% when the instructions of the manufacturer for the LA technique were followed. Agreement of 99% was obtained when modified autoclave extracts were used as antigens in the LA procedure. A total of 82 strains of non-beta-hemolytic streptococci were also tested by conventional, prescribed LA, and modified autoclave procedures. The agreement between conventional techniques and both LA procedures was 76%. However, when serological cross-reactions in the conventional grouping procedures were considered as errors, the accuracy of identification of both LA procedures was 88% among the non-beta-hemolytic strains. Of 13 strains of Streptococcus bovis, 10 did not react with the LA group D reagent but were serogroup D by conventional techniques. More S. bovis strains were grouped by the LA technique when extracts of 20 ml of broth cultures were used as antigens; however, cross-reactions were observed with non-group D strains when this technique was applied to them.
Destruction of bacterial viruses in serum by heat and radiation under conditions that sustain the ability of serum to support growth of cells in suspended culture
Authors: Ward R L
Published: January 2020

Methods for inactivating bacterial viruses in serum were developed through the use of heat and ionizing radiation, and the effects of these treatments on the growth rates of cultured cells were tested. Viruses chosen for this study were the radiation-resistant bacteriphage f2 and heat-resistant phage T4. The viabilities of these phages were reduced more than 2 and 4 orders of magnitude, respectively, by a treatment at 60 degrees C for 30 min followed by 420 krads of ionizing radiation. Simultaneous application of heat and radiation caused a considerably greater reduction in viability of both phages in serum, but also caused a significant decrease in the growth rates of L cells in medium supplemented with serum treated in this manner. Treatment of serum with these same doses but given in the sequential fashion of heat followed by radiation caused little or no change in the growth rates of L cells. Finally, it was found that simultaneous treatment of serum with these doses of heat and radiation had little effect on the growth rates of either HeLa or Chinese hamster cells.
Effect of osmotic stabilizers on radiometric detection of cell wall-damaged bacteria
Authors: Martinez O V , Malinin T I
Published: January 2020

The effect of osmotic stabilizers on the 14CO2-dependent radiometric detection of cell wall-damaged Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa was studied in BACTEC 14C-labeled blood culture medium. The organisms were previously exposed to cefamandole or carbenicillin at 63 to 80% of the minimum inhibitory concentrations. The addition of 10% sucrose, 2.2% glycerol, and 2.2% ethylene glycol to the medium failed to reduce the time required for detection and diminished the amounts of 14CO2 released by the growing cultures. Viable counts made after 4 to 7 h of incubation showed a decreased culture density in osmotically stabilized media as compared with saline or Ficoll controls. Sucrose and Ficoll had little or no inhibitory effect on 14CO2 evolution by P. aeruginosa. The osmotic stabilizers tested did not seem to improve the survival of the bacterial inoculum and failed to increase the sensitivity of the radiometric system of detection.
Comparison of sputum counterimmunoelectrophoresis and culture in diagnosis of pneumococcal pneumonia
Authors: Downes B A , Ellner P D
Published: January 2020

The diagnostic value of counterimmunoelectrophoresis performed on sputum was compared with that of sputum culture. The detection of pneumococcal polysaccharide in sputum showed a better correlation with the presence of pneumococcal pneumonia than the recovery of pneumococci by culture. The authors conclude that sputum counterimmunoelectrophoresis can provide diagnostic guidance to physicians awaiting the results of sputum culture and aid in the interpretation of cultural findings.
Lectins in diagnostic microbiology: use of wheat germ agglutinin for laboratory identification of Neisseria gonorrhoeae
Authors: Schaefer R L , Keller K F , Doyle R J
Published: January 2020

A lectin slide agglutination test has been developed for the confirmatory identification of Neisseria gonorrhoeae. With wheat germ lectin as an agglutinin, 164 of 165 clinical isolates of N. gonorrhoeae gave a 3 to 4+ reaction within 6 to 8 min. Four gonococcal isolates, even though negative by the fluoresecent-antibody method, gave strong positive reactions with the wheat germ lectin. Among 23 isolates of Neisseria meningitidis tested, which included representatives of sero-groups A, B, C,D, X, Y, and Z, only one strain in group X gave a false-positive reaction. The nonpathogenic species of Neisseria, as well as Branhamella catarrhalis, all showed negative reactions with the wheat germ agglutinin. The novel method provides a simple, rapid, and inexpensive means for the laboratory diagnosis of gonorrhea and obviates the need for performing second-stage sugar fermentation studies or utilizing the more expensive fluorescent-antibody techniques.
Indirect hemagglutination test for detection of antibody to Rickettsia rickettsii in sera from humans and common laboratory animals
Authors: Anacker R L , Philip R N , Thomas L A , Casper E A
Published: January 2020

Antibody production in humans and three species of laboratory animals infected with Rickettsia rickettsii was determined with the indirect hemagglutination test. Rabbits, guinea pigs, and mice were inoculated with R. rickettsii and bled at intervals. Antibody which agglutinated both fresh and glutaraldehyde-fixed sheep erythrocytes sensitized with antigen prepared either from purified rickettsiae or from infected yolk sacs was found in rabbit sera at all intervals tested (10 to 59 days postinfection). Antibody which agglutinated fresh but not glutaraldehyde-fixed erythrocytes sensitized with either of the above antigens was detected in guinea pig sera obtained 7, 14, and 28 days postinfection. Antibody was found in mice inoculated with 5.6 x 10(6) plaque-forming units of R. rickettsii but not in mice given 5.6 x 10(2) plaque-forming units. Peak indirect hemagglutination titers occurred in nonvaccinated human Rocky Mountain spotted fever patients about 3 weeks after onset of illness, and antibody was still detectable after 1 year. Both human immunoglobulin G and human immunoglobulin M antibodies agglutinated sensitized cells, but immunoglobulin M antibodies apparently were more efficient. The indirect hemagglutination test is useful for the titration of human, rabbit, guinea pig, and mouse antibodies when the appropriate erythrocytes are used.
Analysis of nonspecific reactions in enzyme-linked immunosorbent assay testing for human rotavirus
Authors: Yolken R H , Stopa P J
Published: January 2020

Solid-phase enzyme immunoassays can be utilized to detect antigens directly in clinical specimens. However, a small number of stools which we tested for human rotavirus by enzyme-linked immunosorbent assay (ELISA) were found to have nonspecific activity in the absence of rotaviral antigen. Similar nonspecific activity was found in eight of eight sera which contained rheumatoid factor. This nonspecific activity was markedly reduced by pretreatment of the specimens with reducing agents, normal goat serum, and anti-human immunoglobulin M (IgM). Thus, it is likely that these specimens contain an IgM antibody capable of reacting nonspecifically with the other components of the assay. Although pretreatment with the mild reducing agent N-acetylcysteine markedly reduced this nonspecific activity, such treatment did not reduce the specific ELISA activity due to rotavirus. Other treatments did produce a reduction in specific activity. Thus pretreatment with N-acetylcysteine offers a practical means to increase the specificity of ELISA systems without reducing their sensitivity.
Evaluation of a killed Rocky Mountain spotted fever vaccine in cynomolgus monkeys
Authors: Gonder J C , Kenyon R H , Pedersen C E
Published: January 2020

A nonhuman primate model of Rocky Mountain spotted fever infection was developed in cynomolgus monkeys (Macaca fascicularis) infected by the subcutaneous route or by aerosol. Clinical responses, hematology and serum chemistry values, and pathological findings were similar to those found in humans ill with Rocky Mountain spotted fever. The clinical model was then used to test the efficacy of a killed Rocky Mountain spotted fever vaccine grown in chicken embryo cells. Monkeys were immunized with varying dilutions of the vaccine with a two-dose schedule and then challenged at 2 months with virulent Rickettsia rickettsii by the subcutaneous route or by aerosol. The undiluted vaccine totally protected monkeys against both challenges, even at extremely high doses.
Detection of herpes simplex virus infection of female genitalia by the peroxidase-antiperoxidase method alone or in conjunction with the Papanicolaou stain
Authors: Pearson N S , Fleagle G , Docherty J J
Published: January 2020

The sensitive peroxidase-antiperoxidase (PXAPX) method individually and in conjunction with the Papanicolaou (PAP) stain was used to detect herpes simplex virus (HSV) in specimens from human female genitalia. Initial studies using a model system of HSV-1 or HSV-2-infected Vero cells established (i) acetone as the most effective fixative, (ii) optimal dilutions of preimmunization and anti-HSV serum for differentiation of infected from noninfected cells, (iii) optimal concentration of 3,3'-diaminobenzidine tetrahydrochloride and H2O2 for maximal staining of infected cells with minimal background reaction, and (iv) removal of endogenous peroxidase with absolute MeOH. These various parameters, once established, were utilized in the PXAPX or PXAPX-PAP on human specimens from the vulva or cervix. In these specimens, examined by standard light microscopy, PXAPX-positive cells were dark brown with a single nucleus or multiple nuclei. By coupling the PAP to the PXAPX, detailed nuclear observations of PXAPX-positive cells were possible and revealed nuclear changes consistent with HSV infection, including syncytium formation, chromatin condensation, and an occasional Cowdry type A inclusion. The PXAPX and PXAPX-PAP correlated (r = 0.742) over a period of 72 h with HSV isolation from these samples.
Role of bacterial growth rates in the epidemiology and pathogenesis of urinary infections in women
Authors: Anderson J D , Eftekhar F , Aird M Y , Hammond J
Published: January 2020

The mean minimum generation time in shake culture in urine of 6 urinary isolates of Escherichia coli (21.7 +/- 0.6 min) was significantly shorter (P = 0.0003) than that of 14 isolates of less common urinary pathogens (46.0 +/- 18.6 min). Mixed populations of approximately equal numbers of E. coli cells paired with other urinary, fecal, and urethral organisms were introduced into a laboratory model of the lower human urinary tract. This model used urine as a medium and reproduced some features of the balance between bacterial growth and the flushing effect of urine. After 24 h E. coli formed greater than or equal to 99% of the bacterial population in the bladder model for 16 our of 18 pairs of isolates examined. Relatively high oxygen tensions in urine sample from 18 healthy women (10.9 +/- 22. kPA) and 18 infected patients (8.0 +/- 4.3 kPa) may explain why anaerobic urinary infections are uncommon. The rapid growth rate of E. coli may be one explanation why it is the commonest cause of urinary infection even though it is relatively uncommon at the urethral meatus.
Isolation of the major herpes simplex virus type 1 (HSV-1)-specific glycoprotein by hydroxylapatite chromatography and its use in enzyme-linked immunosorbent assay for titration of human HSV-1-specific antibodies
Authors: Vestergaard B F , Grauballe P C
Published: January 2020

A 131,000 molecular weight herpes simplex virus type 1 (HSV-1) glycoprotein designated antigen number 6 (Ag-6) was previously shown to possess almost exclusively HSV-1-specific antigenic sites. Fused rocket and crossed immunoelectrophoresis of fractions obtained from hydroxylapatite chromatography of crude HSV-1 antigen (Triton X-100-solubilized, infected tissue culture cells) showed that a subfraction of Ag-6 could be separated from the other HSV antigens. Enzyme-linked immunosorbent assay with the isolated Ag-6 showed that sera from rabbits infected with HSV-1 and HSV-1 human antisera contained antibodies to Ag-6, whereas sera from HSV-2-infected rabbits and sera from patients with primary HSV-2 infections did not react with Ag-6. Enzyme-linked immunosorbent assay of 852 human sera for antibodies to HSV type-common glycoproteins, Ag-6, and HSV 2-specific antigens showed that 139 sera which reacted negatively with HSV type-common glycoproteins also did not react with Ag-6 with HSV-2 specific antigens. The 713 sera reacting positively to HSV type-common antigens either reacted with Ag-6 (328 sera) or with HSV-2-specific antigens (31 sera) or both (354 sera). This means that Ag-6 might be useful in large-scale human serology for the detection of past infection with HSV-1, irrespective of whether or not past infection with HSV-2 has occurred.
Evaluation of enzyme-linked immunosorbent assay for the serodiagnosis of amebiasis
Authors: Yang J , Kennedy M T
Published: January 2020

This report describes the development and evaluation of an enzyme-linked immunosorbent assay (ELISA) for the detection of antibodies to Entamoeba histolytica. Highly sensitive and reproducible results were obtained in antigen-coated plates prepared by air-drying at 37 degrees C. Comparison of the ELISA with indirect fluorescent antibody and indirect hemagglutination techniques showed that the former was slightly more sensitive than the two latter methods. The specificity was evaluated by testing specially chosen population groups. ELISA was negative in 96.4% of 693 normal adults and children and in 96.6% of 377 patients with various parasitic, bacterial, mycotic, and other clinical diseases. The assay was positive in 26% of 461 patients with suspected amebiasis and in all of 53 patients with amoebic liver abscess. The ELISA was found to be a specific, highly sensitive, and reliable procedure for detecting anti-E. histolytica antibodies in humans.
Simplification of methods for the production and storage of specimens to be tested for heat-stable enterotoxin of Escherichia coli
Authors: Gomes J A , Rodrigues A C , Simóes M , Serafim M B , De Castro A F
Published: January 2020

Experiments with the infant mouse test demonstrated that there is no need of shaking for heat-stable Escherichia coli enterotoxin production when low volume of medium per volume of flask ratios are used in stationary cultures. Centrifugation and filtration of the cultures to be tested are not necessary either, and Merthiolate (1:10,000) used as preservative has no deleterious effect on heat-stable enterotoxin activity. Based upon these findings, some modifications of the procedures for production and storage of heat-stable enterotoxin preparations are suggested. Standardized pieces of filter papers are wetted with Merthiolated stationary cultures which are to be assayed for heat-stable enterotoxin activity by the infant mouse test. From dried filter papers, heat-stable enterotoxin can be eulted unaltered up to 2 months after specimen preparation. With the proposed modifications, even modestly equipped laboratories will be able to carry out the infant mouse test or at least to prepare specimens to be assayed by more specialized laboratories.
Cultivation of Pneumocystis carinii with WI-38 cells
Authors: Bartlett M S , Verbanac P A , Smith J W
Published: January 2020

Pneumocystis carinii has been successfully cultured with WI-38 human embryonic lung fibroblasts. Inoculum was obtained from infected lungs of cortisone-treated Sprague-Dawley rats. Trophozoites reached peak numbers between days 4 and 8 and grew in two subcultures, but then proliferation ceased. If primary cultures were harvested and new medium were added, a second and sometimes a third harvest could be obtained. Cell monolayers were not destroyed. After growth of the initial inoculum had ceased, monolayers supported growth of a new inoculum. Harvested organisms had few contaminating tissue culture cells. Additional studies of growth requirements are needed. Although cultures cannot be used to diagnose P. carinii infection, cultured organisms should be useful for studies of biology and pathogenesis and for the development of immunodiagnostic techniques.
Center for Disease Control Diagnostic Immunology Proficiency Testing Program results for 1978
Authors: Taylor R N , Fulford K M , Przybyszewski V A , Pope V
Published: January 2020

Data from about 1,000 laboratories participating in the Diagnostic Immunology portion of the 1978 Center for Disease Control Proficiency Testing Program provided information dealing with laboratory performance and trends in testing protocols. Ninety specimens were distributed in scheduled quarterly and semiannual shipments, and five additional specimens were provided in a special survey. The specimens offered both qualitative and quantitative challenges for a wide variety of analytes which included syphilis serology, rheumatoid factor, bacterial agglutinins, hepatitis B surface antigen, immunoglobulins and other serum proteins, infectious mononucleosis, rubella, toxoplasma, antinuclear antibodies, and streptococcal exoenzymes. This paper summarizes the results of the 1978 program.
Serological cross-reactions between Acinetobacter calcoaceticus and chlamydiae
Authors: Brade H , Brunner H
Published: January 2020

A cross-reaction between Acinetobacter calcoaceticus and chlamydiae is described. A water-soluble, heat stable, non-dialyzable antigen was extracted from Acinetobacter species by boiling. This antigen fixed complement in the presence of homologous hyperimmune sera from rabbits or guinea pigs and in the presence of heterologous human or hyperimmunized animal sera containing chlamydial antibodies. Hyperimmune antisera to the extracted antigen, or to suspensions of live acinetobacters, also reacted in complement fixation with a group-specific antigen.
The Automicrobic System for urines
Authors: Nicholson D P , Koepke J A
Published: January 2020

An evaluation of the Automicrobic System (AMS) for Urines (Vitek Systems, Inc.) was carried out under the auspices of the Product Evaluation Committee of the College of American Pathologists from the period June 1977 through October 1978. Data generated during this evaluation indicated that, when comparing the AMS methodology to our clinical microbiology laboratory methodology, a 37% time saving could be realized by utilizing the AMS. Quantitation with the AMS showed a 99% correlation with the clinical microbiology laboratory method except for yeast which correlated only 50% of the time. The average overall identification accuracy was 95%. Negative response accuracy was 99%. Other members of the Enterobacteriaceae which the instrument is not designed to identify may produce erroneous results if they occur in urine specimens. Specimens containing two organisms were identified with a 94% correlation when compared to our conventional methodology. The time when a well becomes positive may be used as a fairly reliable indicator of significance (count greater than 70,000 colony-forming units per ml) for Escherichia coli, Klebsiella-Enterobacter group, and group D Enterococcus, but not for Proteus sp., Pseudomonas aeruginosa, and yeast. Specimen collection must be performed properly since specimens considered as contaminated by conventional plating-out techniques may be reported out by the AMS as only one or two organisms and thus lead to an erroneous assumption as to significance. Cost per specimen was $1.83 more by utilizing the AMS method as compared to our conventional method. This is offset by a saving of 1.74 h daily of personnel time and a final report in 13 h. At least 30 urine specimens would be needed daily to pay for the instrument and specimen costs in 1 year. The AMS can provide significant aid to a clinical microbiology laboratory when all factors are considered.
Methods of measuring zones of inhibition with the Bauer-Kirby disk susceptibility test
Authors: Barry A L , Coyle M B , Thornsberry C , Gerlach E H , Hawkinson R W
Published: January 2020

Standard Bauer-Kirby disk tests were performed with 85 selected isolates, each tested in triplicate by four different investigators. Each disk test was observed, and zone diameters were measured, under two lighting conditions (transmitted light and reflected light). The two lighting systems produced similar zone measurements (+/-2 mm) with 96% of the tests. When there were greater differences, zones appeared to be larger when observed with reflected light. Interlaboratory reproducibility was much greater when using reflected light rather than transmitted light. We concluded that zone diameters should be measured from the back of the plate while it is resting on, or held 2 to 3 inches [ca. 5.1 to 7.6 cm] above, a black, nonreflecting, flat surface, illuminated by a reflected light source.
Analysis of Vibrio parahaemolyticus soluble antigens by employing passive hemagglutination
Authors: Sochard M R , Colwell R R
Published: January 2020

The passive hemagglutination assay was explored as a sensitive test of immunological reactivity of endotoxin and other antigens prepared from selected strains of Vibrio parahaemolyticus. The tannic acid procedure for passive hemagglutination, commonly used with protein antigens, was the only procedure yielding good results with V. parahaemolyticus protein extracts, endotoxins, and related preparations. These results were probably due to the presence of large amounts of protein in the V. parahaemolyticus endotoxins as determined by earlier work referenced in the text. Glucose and galactose as possible antigenic determinants in the endotoxin of a Vibrio strain were tested by inhibition tests. Cross-reactions were observed between endotoxin preparations, but were low in hemagglutination, suggesting reactions of common generic antigens. The ability of V. parahaemolyticus endotoxins to stimulate production of antibodies was determined.
Simple inoculum standardizing system for antimicrobial disk susceptibility tests
Authors: Barry A L , Amsterdam D , Coyle M B , Gerlach E H , Thornsberry C , Hawkinson R W
Published: January 2020

A collaborative study was undertaken to evaluate a simple, convenient device which expedites inoculum standardization for antimicrobial disk susceptibility tests. The Inocupac system (Minnesota Mining & Manufacturing [3M] Co., St. Paul, Minn.) was used to perform disk tests in parallel with the standard Bauer-Kirby method. Five investigators tested 100 selected isolates, each in triplicate. Inter- and intralaboratory precision of both disk procedures was essentially comparable. The Inocupac system failed to consistently provide satisfactory growth with some streptococci, but when testing common gram-negative bacilli, staphylococci, and most enterococci, the Inocupac system gave zones about the same size (+/-2 mm) as the Bauer-Kirby procedure. Interpretive agreement between the two test systems varied from 90 to 99% with different antimicrobial agents, and repeated tests with the Bauer-Kirby method demonstrated the same degree of interpretive agreement. The Inocupac system is a valid alternative method for inoculating disk susceptibility tests.
Lack of correlation between interferon production of mononuclear cells and virus replication in chronic hepatitis B virus infection
Authors: Kinoshita R , Miura K , Suzuki S , Uchino H
Published: January 2020

Interferon production in hepatitis B virus carriers with normal liver functions was preserved, whereas in carriers with chronic hepatitis it was depressed. The lower interferon production in hepatitis B virus carriers with chronic hepatitis appears to be the result rather than the cause of chronic hepatic disease.
Detection of oral anaerobic spirochetes in dental plaque by the indirect fluorescent-antibody technique
Authors: Jacob E , Allen A L , Nauman R K
Published: January 2020

The indirect fluorescent-antibody technique was found to be a rapid and sensitive tool for the detection of oral anaerobic spirochetes in dental plaque.
Aerobically incubated medium for decarboxylase testing of Enterobacteriaceae by replica-plating methods
Authors: Maccani J E
Published: January 2020

An aerobically incubated, agar-based medium was developed for amino acid decarboxylase testing of Enterobacteriaceae family members by replica-plating methods. Results with the new medium agreed 97 to 99% with the reference broth method of Moeller, and no false-positive reactions were encountered.
Pharmacokinetic properties of human fibroblast and leukocyte interferon in rabbits
Authors: Vilcek J , Sulea I T , Zerebeckyj I L , Yip Y K
Published: January 2020

When rabbits were given intramuscular injections of the same quantities of human leukocyte or fibroblast interferons, the former produced moderately higher levels of circulating interferon. Fibroblast interferon was not cleared faster from circulation, nor was direct inactivation by rabbit blood responsible for this difference.
Yersinia pseudotuberculosis: use of cold-temperature enrichment for isolation
Authors: Oberhofer T R , Podgore J K
Published: January 2020

The successful isolation of Yersinia pseudotuberculosis from the stool of an asymptomatic family member of a patient with yersinia septicemia is presented. Cold enrichment permitted the isolation after 4 weeks of refrigerator incubatio,.
Comparison of serum and plasma specimens for syphilis serology using the reagin screen test
Authors: Dyckman J D , Wende R D
Published: January 2020

One serum and three plasma samples were obtained from each of 125 normal individuals and from 140 patients with treated or untreated syphilis. Serum samples were tested by the Venereal Disease Research Laboratory (VDRL) test and by the Reagin Screen Test (RST). Plasma specimens were tested only with the RST. When tested within 24 h after collection, all specimens from normal individuals were nonreactive. Plasma specimens from normal individuals stored for up to 72 h after collection continued to yield a clearly nonreactive result in 423 of the 426 samples tested by the RST. Serum and plasma samples from syphilis patients tested within 72 h after collection by the RST yielded qualitative and quantitative results almost identical to results of serum tested by the VDRL test.
Liquid medium for growth of Legionella pneumophila
Authors: Ristroph J D , Hedlund K W , Allen R G
Published: January 2020

The medium described is a simple yeast extract broth capable of growing large number of Legionella neumophila, the causative organism of Legionnaires disease. Filtration was chosen as a means of sterilization, since medium that was autoclaved did not support growth without the presence of Norite A. The filtered medium gave rapid cell growth and maintained the initial antigen production. The observed generation time was 99 min with a maximum cell population of 2 X 10(2) COLONY-FORMING UNITS PER ML IN APPROXIMATELY 40 H.
Cross-reaction to Legionella pneumophila antigen in sera with elevated titers to Pseudomonas pseudomallei
Authors: Klein G C
Published: January 2020

A significantly greater incidence (P less than 0.005) of Legionella pneumophila microagglutination titers greater than or equal to 32 was found in sera with elevated titers to Pseudomonas pseudomallei as compared with sera with negative titers for P. pseudomallei antibodies. The greater incidence of L. pneumophila titers in these sera suggests that L. pneumophila and P. pseudomallei share an antigen. The incidence of L. pneumophila microagglutination titers of greater than or equal to 32 in sera with elevated titers to Brucella abortus or Francisella tularensis is not statistically significant.
Antimicrobial Activity of Heparin
Authors: Rosett Walter , Hodges Glenn R.
Published: January 2020

Single clinical isolates of eight species of microorganisms were incubated in solutions of heparin and brain heart infusion broth at various concentrations to determine the possible antibacterial effect of heparin. At heparin concentrations ranging from 12.5 to 400 U/ml, the effect on
Escherichia coli, Pseudomonas aeruginosa, Candida albicans, Staphylococcus aureus,
and
S. epidermidis
varied with brain heart infusion broth concentrations of 1.2 to 10% and inocula of 10
2
to 10
6
colony-forming units per ml; similar effects were not observed with
Klebsiella pneumoniae, Enterobacter aerogenes,
and
Citrobacter
spp. The minimal inhibitory concentrations of heparin for ten strains of each species were determined in 2.5% brain heart infusion broth with inocula of 10
4
colony-forming units per ml. All 10 isolates of
S. aureus
and all 10 of
S. epidermidis
were inhibited by heparin concentrations of 125 to 500 U/ml. Three
E. coli,
four
P. aeruginosa,
and nine
C. albicans
strains were inhibited by ≤500 U of heparin per ml. None of the
K. pneumoniae, E. aerogenes, Enterobacter cloacae,
and
Citrobacter
spp. was inhibited by heparin at ≤500 U/ml. Heparin inhibition of
S. aureus
in 2.5% brain heart infusion broth-500 U of heparin per ml could be quantitatively overcome by addition of magnesium, calcium, or magnesium and calcium. These data suggest that the growth of microorganisms from heparin-containing material may be suppressed.
Microtiter ganglioside enzyme-linked immunosorbent assay for vibrio and Escherichia coli heat-labile enterotoxins and antitoxin
Authors: Sack D A , Huda S , Neogi P K , Daniel R R , Spira W M
Published: January 2020

We have developed a microtiter enzyme-linked immunosorbent assay method for detecting the heat-labile enterotoxins of Vibrio cholerae and Escherichia coli using GM1 ganglioside as the base coat. This method compares favorably with a similar assay using anticholera toxin as the base coat, and with the Y1 adrenal cell assay. The assay should be useful in detecting enterotoxin production in E. coli and vibrios (including non-agglutinating Vibrio), in quantitating the toxin, and in determining binding properties of enterotoxins to ganglioside. The assay can also be used to quantitate antibodies which block the attachment of the toxin to the ganglioside.
Coagglutination as an expedient for grouping Escherichia coli associated with urinary tract infections
Authors: Hovanec D L , Gorzynski E A
Published: January 2020

Thirteen serogroups of Escherichia coli most frequently are responsible for urinary tract infections in humans. Knowledge of serogroup is required for epidemiological reasons and to help differentiate between new and reemergent strains in infected patients. Coagglutination and bacterial agglutination were compared as serodiagnostic tools for identifying groups of E. coli associated with these infections. In contradistinction to bacterial agglutination, coagglutination showed no cross-reactions for 12 of the 13 known strains obtained from the Center for Disease Control. A single antiserum, E. coli O4, caused bacterial agglutination and not coagglutination. In addition, staphylococcal cells that were coated with antiserum reacted with sheep erythrocytes that had been treated with soluble extract of E. coli. The latter reaction, cohemagglutination, was as specific and rapid as coagglutination; easily visible patterns of clumping developed within 1 min after sensitized staphylococci and E. coli reagent were mixed. These results revealed a method that is sensitive and reproducible for identifying serogroups of E. coli responsible for urinary tract infections.
Rapid differentiation of the major causative agents of bacterial meningitis by use of frequency-pulsed electron capture gas-liquid chromatograph: analysis of acids
Authors: Brooks J B , Kellogg D S , Shepherd M E , Alley C C
Published: January 2020

The major causative agents of bacterial meningitis, Haemophilus influenzae serogroup B, Neisseria meningitidis serogroups B and C, Klebsiella pneumoniae, Streptococcus pneumoniae, and two types of Escherichia coli, were cultured in a modified chemically defined Catlin medium and in a commercial version of the unmodified Catlin medium. The spent media were extracted under acidic conditions, and electron-capturing derivatives were prepared by derivatization with trichloroethanol or haptafluorobutyric anhydride. The derivatives were analyzed on a gas chromatograph equipped with a frequency-pulsed electron capture detector and a PEP-2 computer. The data obtained from the study show that these organisms can be easily distinguished from each other on the basis of metabolic products detected in either type of medium. Three different metabolic groups were detected within two serogroups of N. meningitidis. The methods are practical, and the new technique should offer clinical laboratories and hospitals a better method for rapid identification of this important group of pathogens.
Comparison of plasma extraction techniques in preparation of samples for endotoxin testing by the Limulus amoebocyte lysate test
Authors: DuBose D A , Lemaire M , Basamania K , Rowlands J
Published: January 2020

Due to the presence of inhibitory and possible mimicking substances in plasma difficulties have occurred in the use of the Limulus amoebocyte lysate test. Currently, there are a variety of extraction techniques discussed in the literature which are used to remove these interfering substances, but there is little information comparing these techniques. Five such procedures were compared in their ability to provide an extracted plasma sample in which low levels of endotoxin could be detected by the Limulus amoebocyte lysate test. Results indicated that some procedures adversely affected endotoxin detection. The dilution + heating extraction method was found to be as effective as the widely used chloroform extraction method. Comparison of Limulus amoebocyte lysate test results from healthy human plasma samples extracted by these two methods indicated that lysate type and not extraction procedure was associated with previously reported questionable positive tests. Thus, ambiguities associated with Limulus amoebocyte lysate tests of plasma samples may be due not only to extraction method but also the lysate type employed.
Nonvalue of cold enrichment of stools for isolation of Yersinia enterocolitica serotypes 3 and 9 from patients
Authors: Van Noyen R , Vandepitte J , Wauters G
Published: January 2020

During an 8-year period 14,092 fecal specimens and 1,428 excised appendixes were examined for the presence of Yersinia enterocolitica, with different combinations of direct plating media and enrichment techniques. The combination of direct plating on SS agar and 2 days of enrichment in a modified Rappaport broth at room temperature resulted in the isolation of 100% of serotype 3 and 9 strains. Such strains were recovered from 3.7% of our fecal specimens. Cold enrichment in phosphate buffer further increased the isolation rate, but the additional isolates all belonged to biotype 1. Evidence is presented that biotype 1 strains, at least in Belgium, are not pathogenic for humans. There was a significant affinity of serotype 9 strains for patients suffering from an "appendicular syndrome."