bluuebunny/crossref_metadata_2025 huggingface dataset:
Controlled evaluation of hypertonic sucrose medium for detection of bacteremia and fungemia in supplemented peptone broth
Authors: Weinstein M P , Reller L B , Mirrett S , Wang W L
Published: January 2020

Because the value of hypertonic media in detection of bacteremia and fungemia is controversial, we evaluated supplemented peptone broth (SPB) with 0.03% sodium polyanetholsulfonate with and without 10% sucrose in 5,439 paired blood cultures from adult patients. The aerobic atmosphere, 1:10 ratio of blood to broth, and methods for processing blood cultures were identical. Only cultures with adequate blood samples (greater than or equal to 4 ml) were compared statistically. More clinically important bacteria were recovered from SPB with sucrose (P less than or equal to 0.001), including Staphylococcus epidermidis, Enterobacteriaceae, and Bacteroidaceae. However, only one of nine isolates of Neisseria gonorrhoeae grew in SPB with sucrose. Staphylococci (P less than 0.001), Enterobacteriaceae (P less than 0.01), Pseudomonas aeruginosa (P less than 0.01), and yeasts (P less than 0.05) were detected 1 or more days earlier in SPB with sucrose. The effect of sucrose on blood cultures appears to be medium dependent, based on comparisons of our results with those of published reports.
Evaluation of a rapid system for species identification of alpha-hemolytic streptococci
Authors: Nachamkin I , Lynch J R , Dalton H P
Published: January 2020

A new 4-h commercial system (API 20S; Analytab Products, Plainview, N.Y.) for the identification of streptococci was compared with the conventional biochemical profile method in the species identification of alpha-hemolytic streptococci. A total of 194 clinical isolates (including 74 isolated from blood cultures, 64 isolated from wound cultures, and 56 isolated from respiratory cultures) and 20 reference strains were tested. Only 4 of the 20 reference strains were correctly identified to species level by the API 20S system. Six were identified to group level (viridans), four were incorrectly identified, and six did not conform to the identification key. Of the 194 clinical isolates tested, 79 (39%) were correctly identified to species level, 34 (17.5%) were identified to group level, 34 (17.5%) were incorrectly identified, and 50 (25.8%) did not conform to the identification key. Of the 12 different species of alpha-hemolytic streptococci isolated from clinical specimens, the API 20S system consistently identified Streptococcus faecalis and Streptococcus faecium, but consistently misidentified the other 10 species, especially Streptococcus mitis. Our results indicate that for identification to species level, the API 20S system is of little value for alpha-hemolytic streptococci other than enterococci.
Determination of bacterial meningitis: a retrospective study of 80 cerebrospinal fluid specimens evaluated by four in vitro methods
Authors: Wasilauskas B L , Hampton K D
Published: January 2020

A total of 80 cerebrospinal fluid specimens were analyzed for bacterial meningitis by four procedures readily available to most laboratories. These tests included routine culturing. Gram staining, countercurrent immunoelectrophoresis, staphylococcal coagglutination (CoA) with laboratory-prepared reagents, and CoA with Pharmacia Diagnostics reagents. A total of 56 specimens were positive for bacterial agents by routine culturing: Gram stain results were positive for 64% of all specimens positive by culturing. For 36 specimens from patients with suspected meningitis due to either Haemophilus influenzae type b, Streptococcus pneumoniae, or group B streptococci, detection was 97% with Pharmacia CoA reagents, 94% with laboratory-prepared CoA reagents, 89% with routine culturing, 78% with countercurrent immunoelectrophoresis, and 75% with Gram staining. One specimen which contained Klebsiella pneumoniae was false positive for S. pneumoniae in tests with both of the CoA reagents and in countercurrent immunoelectrophoresis. A Gram stain of this specimen clearly showed gram-negative bacilli, which were confirmed by culturing. Although a positive culture and a positive Gram stain are definitive evidence of bacterial meningitis, rapid immunological tests can provide valuable clinical information as an adjunct to culture and Gram stain results. Serological tests with Pharmacia CoA reagents produced more positive results than either laboratory-prepared CoA reagents or countercurrent immunoelectrophoresis.
Bone infection caused by debaryomyces hansenii in a normal host: a case report
Authors: Wong B , Kiehn T E , Edwards F , Bernard E M , Marcove R C , de Harven E , Armstrong D
Published: January 2020

Debaryomyces hansenii was isolated from a cystic lesion in the distal tibia of a healthy 23-year-old woman. Ascospores were demonstrated when the organism was incubated at 25 but not at 30 degrees C. Electron microscopy was necessary to demonstrate the warty surface of the ascospore wall. Growth was inhibited in vitro by low concentrations of amphotericin B, 5-fluorocytosine, miconazole, and ketoconazole. Four previous cases of infection caused by Debaryomyces spp. and one caused by the related fungus Torulopsis candida were reviewed.
Biotype-Specific Restriction and Modification of DNA in
Vibrio cholerae
Authors: Imbesi Franca , Manning Paul A.
Published: January 2020

By using
Vibrio cholerae
typing phages it was possible to demonstrate that within
V. cholerae
of the O-1 serotype there are at least two biotype-specific DNA restriction and modification systems.
Chorioamnionitis and possible neonatal infection associated with Lactobacillus species
Authors: Lorenz R P , Appelbaum P C , Ward R M , Botti J J
Published: January 2020

A patient is described with premature labor at 32 weeks of gestation complicated by chorioamnionitis associated with Lactobacillus species, subsequent premature delivery, and possible neonatal infection. Mother and infant did well with antibiotic therapy. The significance of chorioamnionitis and neonatal pneumonia due to this organism group is discussed.
Enzymatic profile of Pseudomonas paucimobilis
Authors: Smalley D L
Published: January 2020

Pseudomonas paucimobilis, previously known as group IIK biotype 1, was found to have a significantly different enzyme profile from that of Flavobacterium multivorum, formerly group IIK biotype 2. P. paucimobilis produces several esterases and phosphatases which may contribute to its virulence.
Capture immunoglobulin M system for rapid diagnosis of La Crosse (California encephalitis) virus infections
Authors: Jamnback T L , Beaty B J , Hildreth S W , Brown K L , Gundersen C B
Published: January 2020

A capture immunoglobulin M (IgM) enzyme immunoassay was developed to diagnose La Crosse virus infections by the detection of specific IgM in acutephase serum specimens. IgM was detected by the capture IgM system in the serum of 24 of 29 (83%) of the patients studied. In comparison, IgM was detected in 19 of 29 (66%) of the patients by an indirect immunofluorescence technique. Specific IgM was detected in 83% (20 of 24) of patient serum specimens by day 3 after the onset of clinical symptoms.
Single derivatization method for routine analysis of bacterial whole-cell fatty acid methyl esters, including hydroxy acids
Authors: Miller L T
Published: January 2020

Analysis of fatty acid methyl esters prepared from whole-cell bacteria by sodium hydroxide hydrolysis and boron trichloride-catalyzed methylation showed degradation of hydroxy acid peaks after several injections on a fused silica capillary column. A simple base wash of the extracts before injection prevented the tailing of the hydroxy acid peaks even after extended use. This eliminates the need to form trifluoroacetic anhydride derivatives of the hydroxy acids.
Influence of a blood culture inoculation technique on detection of bacteremia by the BACTEC system
Authors: Carlson L G , Plorde J J
Published: January 2020

A 2-year study compared the influence of blood culture inoculation technique on the detection of bacteremia by an automated radiometric system (BACTEC; Johnston Laboratories, Inc.). A total of 4,690 specimens (20 ml each) were collected. Of each sample, 10 ml was inoculated into a pair of Bactec bottles at the bedside (BACTEC system). The remaining 10 ml was placed in an evacuated blood collection tube (VACUTAINER; Becton Dickinson VACUTAINER Systems) and transported to the laboratory for subsequent inoculation into an identical set of vials (VACUTAINER-BACTEC system). A total of 309 cultures grew organisms considered to be clinically significant. The recovery rate, time to positivity, and spectrum of isolates were similar for the two methods. There were substantially more sporeforming "contaminants" isolated in the VACUTAINER-BACTEC system.
Isolation of Clostridium difficile from hospitalized patients without antibiotic-associated diarrhea or colitis
Authors: Varki N M , Aquino T I
Published: January 2020

Stool samples from 100 hospitalized patients and 21 healthy adults, obtained between March and June 1980, were cultured on a special selective medium containing cefoxitin and cycloserine to detect Clostridium difficile. This organism was isolated from 13 of the hospitalized patients and from 1 healthy subject. None of the patients with positive cultures had received antimicrobial therapy in the 3 preceding months. The observed rate of C. difficile isolation from adults not suffering from antibiotic-associated diarrhea or colitis is higher than previously reported. C. difficile culture is not recommended as a substitute for toxin assay in the evaluation of patients with intestinal disorders after antimicrobial chemotherapy.
Broth microdilution testing of Pseudomonas aeruginosa and aminoglycosides: need for employing dilutions differing by small arithmetic increments
Authors: Woolfrey B F , Fox J M , Lally R T , Quall C O
Published: January 2020

The use of dilutions differing by small arithmetic increments was studied as a means for improving the definition and measurement of minimum inhibitory concentrations and precision parameters for testing Pseudomonas aeruginosa versus the aminoglycosides by the broth microdilution test. For five strains of P. aeruginosa versus gentamicin, tobramycin, and amikacin, comparisons were made of minimum inhibitory concentrations which were replicated in parallel by using three microdilution systems: small increment panels prepared by us, modified twofold dilution panels prepared by us, and similar modified twofold dilution panels obtained commercially. The small increment dilutions were prepared to differ by concentrations of 1.0 microgram/ml for gentamicin and tobramycin and by 2.0 micrograms/ml for amikacin. Use of the small increment dilutions resulted in the ability to measure minimum inhibitory concentrations at more closely spaced intervals than those dictated by modified twofold dilution schemes, and confidence limits were significantly improved. The average coefficient of variation for the small increment microdilution test results was 9.5%, with 99.5% of minimum inhibitory concentrations falling within +/- 2 small increment dilutions from their modal values.
Enzyme immunofiltration technique for rapid diagnosis of herpes simplex virus eye infections in a rabbit model
Authors: Cleveland P H , Richman D D , Redfield D C , Disharoon D R , Binder P S , Oxman M N
Published: January 2020

A rapid enzyme immunofiltration assay for herpes simplex virus (HSV) has been developed which is sensitive enough to detect viral antigens in eye swabs from rabbits with primary herpes keratitis. This assay employs a specially designed filter manifold to immobilize whole cells and cell debris dissociated from the swabs. Viral antigens trapped on the filters are then detected in an indirect immunoassay utilizing staphylococcal protein A conjugated with horseradish peroxidase. The assay required only 2.5 h to perform and could be read visually. Reconstruction experiments indicated that antigen from as few as 49 HSV-infected cells could be detected. Calcium alginate swabs were shown to recover more viral antigen than dacron swabs. The enzyme immunofiltration assay detected HSV antigens on 95% of the eye swabs from which infectious virus was recovered. In addition, HSV antigen was also detected in several swabs from infected eyes which did not yield infectious virus, presumably because the virus was neutralized by native antibody present in the lacrimal fluid. This enzyme immunofiltration assay technique lends itself to the elution of native antibody bound to the viral antigens, and this may be especially applicable in the diagnosis of recurrent HSV keratitis, where antiviral antibody in the lacrimal fluid may interfere with virus isolation and fluorescent-antibody or other virus detection assays.
Enzymatic characterization of Aeromonas hydrophila complex by the API ZYM system
Authors: Waltman W D , Shotts E B , Hsu T C
Published: January 2020

Enzymatic characterization of 48 Aeromonas hydrophila complex isolates from various sources was determined with the API ZYM system (Analytab Products, Plainview, N.Y.). All isolates lacked valine and cystine aminopeptidases, chymotrypsin, alpha-mannosidase, alpha-fucosidase, alpha-galactosidase, and beta-glucuronidase but possessed caprylate esterase-lipase, leucine aminopeptidase, acid phosphatase, phosphoamidase, and N-acetyl-beta-glucosidase. Variability was found in the presence of alkaline phosphatase, butyrate esterase, myristate lipase, trypsin, beta-galactosidase, alpha-glucosidase, and beta-glucosidase. No significant differences were evident among the enzymatic profiles of isolates from various sources.
Immunological detection of the Kanagawa phenomenon of vibrio parahaemolyticus on modified selective media
Authors: Honda T , Sornchai C , Takeda Y , Miwatani T
Published: January 2020

Selective media for Vibrio parahaemolyticus, BTB-Teepol agar and modified arabinose-ammonium sulfate-cholate agar, were modified for use in immunological detection of the thermostable direct hemolysin produced by this organism. The modified BTB-Teepol agar and modified arabinose-ammonium sulfate-cholate agar were both found to be useful for the modified Elek test and immunohalo test with antiserum (or immunoglobulin G) against the thermostable direct hemolysin. With these modified media it is possible to isolate V. parahaemolyticus and identify the Kanagawa phenomenon on a single plate and thus save time in obtaining results.
Determination of immunoglobulin A in saliva by immunobead enzyme-linked immunosorbent assay: comparison with single radial immunodiffusion
Authors: Bratthall D , Ellen R P
Published: January 2020

For the quantitative measurement of immunoglobulin A in human saliva, an immunobead enzyme-linked immunosorbent assay was investigated in detail. The method proved to be fast and sensitive, and it gave reproducible results. There was a strong correlation with results obtained by a single radial immunodiffusion method. The immunobead method gave 1.8 times higher values than the single radial immunodiffusion method with a lower correction factor for low-immunoglobulin A saliva and a higher factor for immunoglobulin A-rich saliva.
Rapid, modified oxidase test for oxidase-variable bacterial isolates
Authors: Tarrand J J , Gröschel D H
Published: January 2020

A modified oxidase reagent, 1% tetramethyl-p-phenylenediamine in dimethyl sulfoxide, proved superior to the routinely used 1% aqueous tetramethyl-p-phenylenediamine dihydrochloride in detecting weakly oxidase-positive gram-negative bacteria after 24 h of growth on agar media (40 of 40 positive versus 22 of 40 positive). The bacterial inoculum was obtained with a cotton-tipped swab instead of a loop or wooden applicator, and the reaction required less than 15 s.
Growth requirements of Haemophilus somnus
Authors: Merino M , Biberstein E L
Published: January 2020

The growth factor needs of Haemophilus somnus, which have not been defined to date, were found to be provided by 1% IsoVitaleX (IVX; BBL Microbiology Systems) in tryptose broth. Some growth, however, occurred in unsupplemented tryptose broth. Of the ingredients of IVX, cocarboxylase was found to stimulate growth to about the same degree as the total supplement. Cocarboxylase was without direct effect in 2% peptone broth, which supported no growth of 25 H. somnus strains until supplemented with IVX, optimally at the 10% level. This could be substituted for by proportional amounts of cysteine or cystine, but by no other IVX ingredient. Cysteine-cystine and IVX but not cocarboxylase supplementation allowed H. somnus to grow in Eagle minimal medium, a completely synthetic medium, but attempts at serial passage were unsuccessful.
Trimethoprim activity in media selective for Campylobacter jejuni
Authors: Bopp C A , Wells J G , Barrett T J
Published: January 2020

The activity of trimethoprim (TMP) in two selective media used for isolation of Campylobacter jejuni was evaluated. The two selective media, Campy-BAP and Skirrow medium, contain TMP in addition to other antimicrobial agents. The minimal inhibitory concentrations of TMP in blood agar base (basal agar for Skirrow medium) or brucella agar (basal agar for Campy-BAP) for three sensitive control organisms were compared with those in Mueller-Hinton agar, which contains low levels of thymidine. TMP was inactive in both blood agar base and brucella agar, even when lysed horse blood or thymidine phosphorylase was added. TMP had activity when used in combination with the other antimicrobial agents normally included in Skirrow medium and Campy-BAP, probably indicating synergism between TMP and one or more of the other antimicrobial agents. Sheep blood could be substituted for lysed horse blood in Skirrow medium without compromising the activity of TMP.
Haemophilus influenzae: comparison of respiratory tract isolates with genitourinary tract isolates
Authors: Albritton W L , Brunton J L , Meier M , Bowman M N , Slaney L A
Published: January 2020

Haemophilus influenzae isolates recovered from the genitourinary (GU) tract were shown to have a significantly different biotype distribution compared with respiratory tract isolates. Biotype IV strains were recovered more commonly from the GU tract, and most strains were non-serotypable. Antibiotic-susceptible strains isolated from the GU tract more frequently harbored plasmids of less than 10 megadaltons than did antibiotic-susceptible respiratory tract strains. One 2.8-megadalton plasmid resident in a GU tract isolate and one 1.8-megadalton plasmid resident in a respiratory tract isolate were shown to be related to the small ampicillin resistance plasmids previously described in H. influenzae, Haemophilus parainfluenzae, Haemophilus ducreyi, and Neisseria gonorrhoeae. This supports the suggestion that these ampicillin resistance plasmids originated by transposition or recombination of the ampicillin transposon (TnA) with cryptic endogenous Haemophilus plasmids.
Rapid method for determining antimicrobial susceptibility of Haemophilus influenzae
Authors: Smith J A , Ngui-Yen J H , Fothergill J , Porter D
Published: January 2020

A method was developed to determine the susceptibility of Haemophilus influenzae to ampicillin, cefamandole, and chloramphenicol by using the MS-2 system (Abbott Laboratories) for determining minimum inhibitory concentrations (MIC). The MS-2 results for 132 strains of H. influenzae were compared with the results of agar disk diffusion, agar dilution, and beta-lactamase tests. Twenty-four strains (18.2%) of H. influenzae were resistant to ampicillin by the agar dilution method, as opposed to 25 strains by the MS-2 method. For a beta-lactamase-negative strain, the agar dilution MIC was 4 micrograms/ml, and the MS-2 MIC was 16 micrograms/ml. Twenty-one strains produced beta-lactamase; two beta-lactamase-negative strains were resistant by MS-2, agar dilution, and agar disk diffusion. In addition, one beta-lactamase-negative strain, for which the agar dilution MIC was 32 micrograms/ml and the MS-2 MIC was 16 micrograms/ml, was sensitive by agar disk diffusion. Overall, the MS-2 method compared favorably with the agar dilution method for determining the MIC of ampicillin, cefamandole, and chloramphenicol for H. influenzae.
Nonmicrobial alternative to reagent quality control testing
Authors: Reynolds S M
Published: January 2020

The traditional approach to quality control in microbiology involves the routine testing of both media and reagents with live microbial cultures. This is expensive, time consuming, and subject to the variables associated with the use of live organisms. A system of reagent quality control based on the pure chemical form of the metabolic end products important to the identification of the Enterobacteriaceae was evaluated. The metabolite reagent control system is simple, reliable, and extremely cost effective, and it eliminates the need for live microbial cultures and media for reagent quality control.
Pseudomonas aeruginosa colonization in patients with spinal cord injuries
Authors: Gilmore D S , Bruce S K , Jimenez E M , Schick D G , Morrow J W , Montgomerie J Z
Published: January 2020

The prevalence of Pseudomonas aeruginosa colonization of patients with spinal cord injury was studied annually from 1976 to 1980. The urethra, perineum, rectum, drainage bag, and urine of patients on the spinal cord injury service were cultured. A total of 224 men and 32 women were studied. Most patients were managed with an external urinary collection system or padding, with or without intermittent catheterization. P. aeruginosa was cultured from one or more body sites (urethra, perineum, or rectum) in 65% of men and 18% of women. Drainage bags on the beds were frequently colonized with P. aeruginosa (73%). Significant bacteriuria with P. aeruginosa was present in 19% of the men and 13% of the women. P. aeruginosa colonization of body sites in men was closely associated with the use of an external urinary collection system. Significantly greater urethral and perineal colonization was found in men using an external urinary collection system. P. aeruginosa serotype 11 was the predominant serotype for the first 3 years, and the number of patients colonized with serotype 11 increased with length of hospital stay. The prevalence of serotype 11 significantly decreased in the last 2 years. The antibiotic susceptibility of the strains of P. aeruginosa isolated from these patients did not change in the 5 years, except that there was increasing susceptibility to carbenicillin in later years. This increasing susceptibility to carbenicillin was a reflection of a decreased prevalence of serotype 11 in these patients, since serotype 11 was more resistant than other serotypes to carbenicillin.
Isolation and rapid identification of Haemophilus ducreyi
Authors: Hannah P , Greenwood J R
Published: January 2020

During a 2-month period, 62 strains of Haemophilus ducreyi were isolated from 168 genital lesions and 2 lymph node aspirates. Of these strains, 22 were found on both chocolate agar and fetal bovine serum agar supplemented with vancomycin, 29 were found only on chocolate agar, and 9 were found only on fetal bovine serum agar. Two additional strains were isolated on sheep blood agar. All of these isolates were correctly identified with the RapID NH system (Innovative Diagnostic Systems, Inc., Decatur, Ga.) a new identification kit that has a database for Haemophilus, Neisseria, and other genera that include fastidious gram-negative bacilli.
Identification of coagulase-negative staphylococci with the API staph system
Authors: Gemmell C G , Dawson J E
Published: January 2020

A kit for the identification of staphylococci based on the biochemical criteria proposed by Kloos and Schleifer (W.E. Kloos and K.H. Schleifer, J. Clin. Microbiol., 1:82-88, 1975) is now available commercially. The system was used to identify 100 strains of coagulase-negative staphylococci isolated from various body sites as the primary etiological agent of clinical infection. The increasing importance of staphylococci and their resistance to antibiotics provided the rationale for such an investigation. Over 90% of the Staphylococcus isolates were easily identified as to their species on the basis of their reaction profile to 19 biochemical tests included in the kit. The remainder, which showed minor variations, could also be assigned to the various species. Identification of the isolates was as follows: S. epidermidis, 54; S. haemolyticus, 5; S. simulans, 2; S. hominis, 1; S. capitis, 4; S. cohnii, 2; S. warneri, 2; S. xylosus, 8; and S. saprophyticus, 22. Antibiotic sensitivity patterns were determined for each of the isolates. Novobiocin resistance was detected in strains of S. saprophyticus and S. xylosus, a property hitherto recognized in Micrococcus sp. type 3 causing bacteriuria in young women. Resistance to penicillin was widespread among strains of several species, whereas resistance to tetracycline was mainly confined to strains of S. epidermidis. General resistance to sulfamethoxazole and nalidixic acid was found among all strains, with almost uniform sensitivity to the other drugs tested.
Bacteriocin typing of clinical isolates of Enterobacter cloacae
Authors: Traub W H , Spohr M , Blech R
Published: January 2020

A total of 16 selected bacteriocins of Enterobacter cloacae were characterized presumptively. They proved to be noninfectious, sedimentable (105,000 X g), resistant against chloroform and trypsin, and nonfilterable. The host ranges were essentially species specific. Based on susceptibility to one or more of these 16 bacteriocins, 242 of 308 (78.6%) clinical E. cloacae isolates were typed and assigned to 52 provisional bacteriocin types. Several outbreaks of nosocomial cross-infection were discerned retrospectively. Thus, bacteriocin typing of E. cloacae isolates may prove useful for controlling hospital infection.
Correlation of growth of aerobic blood cultures in hypertonic broth with antibiotic therapy
Authors: Eng J , Maeland A
Published: January 2020

The aim of this study was to elucidate the mechanisms by which sucrose improves growth in a hypertonic medium for isolating aerobes from blood. Clinical blood cultures were made routinely in duplicate in plain broth consisting of brain heart infusion broth with sodium polyanetholesulfonate, gelatin, and penicillinase and the same broth with 20% sucrose added. The growth patterns of Staphylococcus aureus and Enterobacteriaceae from plain and from hypertonic broth were correlated with the presence or absence of antimicrobial therapy in patients when the blood cultures were collected. In S. aureus bacteremias, 58.7% of the positive cultures collected during treatment of patients with beta-lactam antibiotics showed earlier growth or growth only in hypertonic broth, compared with 16.7% of the cultures taken during treatment with other antimicrobial agents (P less than 0.05) and 17.6% of the cultures made in antibiotic-free intervals (P less than 0.01). In the group of cultures yielding growth of Enterobacteriaceae, growth occurred earlier or solely in hypertonic broth in 28.9% of the cultures taken during treatment with beta-lactam antibiotics, compared with 15.7% of the cultures taken during treatment with other antimicrobial agents and 21.6% of the cultures collected in antibiotic-free intervals (differences not statistically significant). It is concluded that treatment with beta-lactam antibiotics is an important reason for the improved growth of S. aureus from hypertonic broth, but other factors are also involved.
Long-term clinical, microbiological, and immunological observations of a volunteer repeatedly infected with Chlamydia trachomatis
Authors: Hanna L , Jawetz E , Dawson C R , Thygeson P
Published: January 2020

A blind volunteer was inoculated in one eye with an isolate of Chlamydia trachomatis in 1961 and followed for 20 years. During this time, many observations were made of his clinical responses to the first inoculation and several subsequent inoculations with the same and other strains, chlamydial shedding, and antibody and cell-mediated immune responses. Evidence is presented that partial resistance to chlamydial eye infection developed during repeated infections and that antibodies, cell-mediated immune reactions, and specific antigen in conjunctival cells persisted for many years after the last infection. The antibody response was directed mainly against the original infecting immunotype, regardless of whether the response was restimulated by infection with the same immunotype or with other immunotypes. The lymphocyte stimulation response appeared to be species specific.
Time-resolved fluoroimmunoassay: a new test for rubella antibodies
Authors: Meurman O H , Hemmilä I A , Lövgren T N , Halonen P E
Published: January 2020

A new solid-phase immunoassay, time-resolved fluoroimmunoassay (TR-FIA), for rubella antibody was developed. The test used polystyrene beads coated with rubella antigen as the solid phase and a chelate of the rare earth metal europium as fluorescent label. A fast light pulse from a xenon flash lamp was used to excite the label, and after a 400-mus delay time the emission fluorescence was measured for 500-mus at 1-ms intervals during a total counting time of 1 s. Background fluorescence of short duration caused by fluorescent serum components and scattering could be eliminated by including the delay time. The TR-FIA was compared with hemagglutination inhibition, single radial hemolysis, and two types of radioimmunoassay (RIA) (a commercial RIA [GammaCoat] and a noncommercial RIA [T-RIA]) by using 60 serum specimens from patients with remote rubella infection. Overall agreement of TR-FIA with hemagglutination inhibition and GammaCoat was 96.7%, with single radial hemolysis 98.3%, and with T-RIA 100%. Linear regression coefficients varied from 0.83 to 0.94, the best being obtained with single radial hemolysis and T-RIA. TR-FIA was also found to be suitable for the diagnosis of acute infections, as significant increases of antibody level were detected in all 30 paired serum specimens tested from patients with an acute rubella infection. Sensitivity and specificity comparable to those of RIA and enzyme immunoassay were obtained with TR-FIA. Furthermore, the advantage that TR-FIA has over RIA is that it incorporates a nonisotopic and stable label; its advantage over EIA is that it is easier to standardize because no additional reaction with substrate is required.
Immunity to rotavirus in conventional neonatal calves
Authors: Vonderfecht S L , Osburn B I
Published: January 2020

The local and systemic humoral immune responses to rotavirus were studied in six conventional neonatal calves. Attenuated bovine rotavirus was administered either orally or directly into an isolated intestinal loop. The parameters monitored were neutralizing rotavirus antibody in serum, immunofluorescent and neutralizing rotavirus antibody in intestinal loop washings, and rotavirus antibody-producing cells in intestinal mucosa. An antibody response was observed in the serum and intestinal secretions from one calf only. Viral replication was not detected in the isolated intestinal loop. Rotavirus antibody-producing cells were found in the intestinal mucosa of five calves. Double staining revealed that most of these cells produced antibody of the immunoglobulin A class. The conclusions were: (i) a previously described system to detect rotavirus antibody-producing cells can be used to study immune responses in neonatal calves, (ii) the class or subclass of antibody in rotavirus antibody-producing cells can be determined by double immunofluorescent staining, (iii) neonatal calves respond to rotavirus inoculation with a local immunoglobulin A response, and (iv) most of the rotavirus antibody-producing cells are located in the mucosa of the proximal small intestine.
Microsporum equinum in North America
Authors: Kane J , Padhye A A , Ajello L
Published: January 2020

Microsporum equinum was isolated in Ontario, Canada, from five human and two equine cases of ringworm infection. This dermatophyte was previously recovered from North American horses on several occasions, but was considered to be M. canis. We regard M. equinum as distinct from M. canis. It can be differentiated from M. canis by the smaller size of its macroconidia, its failure to perforate hair in vitro, its poor growth and sporulation on bromocresol purple casein dextrose agar, and its incompatibility with Nannizzia otae, the telemorph of M. canis.
Survival of hepatitis A virus in feces after drying and storage for 1 month
Authors: McCaustland K A , Bond W W , Bradley D W , Ebert J W , Maynard J E
Published: January 2020

Hepatitis A virus in feces remained viable after being dried and then stored at 25 degrees C and 42% relative humidity for 30 days, as evidenced by infection of two marmosets inoculated with 1 ml of the treated fecal material. The virus was excreted in stool specimens from these animals, and seroconversion to antibody to hepatitis A virus occurred 28 and 35 days post-inoculation.
Comparison of two methods for enumeration of mycoplasmas
Authors: Stemke G W , Robertson J A
Published: January 2020

Two methods of viable cell counts were evaluated for Mycoplasma hominis and Ureaplasma urealyticum: color change unit50 and colony-forming unit. The color change unit50 method gave higher estimates of cell numbers; furthermore, the color change unit50 values correlated better with the DNA content of the cell pellet and the published genome sizes.
Gas-liquid chromatography technique for detection of hippurate hydrolysis and conversion of fumarate to succinate by microorganisms
Authors: Kodaka H , Lombard G L , Dowell V R
Published: January 2020

A gas-liquid chromatography technique which allows simultaneous detection of hippuric acid (N-benzoylglycine) hydrolysis and conversion of fumaric acid to succinic acid by microorganisms uses a new medium, hippurate-formate-fumarate broth, and a gas chromatograph equipped with a thermal conductivity detector. This technique gave more reproducible results than other tests used in the study for detecting hippurate hydrolysis and also gave consistent results in detecting succinic acid produced from utilization of fumaric acid.
Detection of circulating free and complexed staphylococcal antigens by enzyme-linked immunosorbent assay
Authors: Lentino J R , Rytel M W
Published: January 2020

An enzyme-linked immunosorbent assay was developed for the detection of circulating free and complexed staphylococcal antigens in various clinical categories of staphylococcal infections. Circulating immune complexes were studied by the polyethylene glycol precipitation method. Circulating immune complexes and staphylococcal antigen (at titers of greater than or equal to 1:32) dissociated from the complexes were found in 7 of 8 patients (87.5%) with staphylococcal endocarditis and in 4 of 20 patients with staphylococcal bacteremia (20%). Although the majority of patients did not have detectable free staphylococcal antigen, it was found in three patients with staphylococcal pneumonia. We conclude that detection of complexed antigen in high titer may differentiate patients with staphylococcal endocarditis from those with other forms of staphylococcal infection or transient bacteremia.
Quantitative microbiological monitoring of hemodialysis fluids: evaluation of methods and demonstration of lack of test relevance in single-pass hemodialysis machines with automatic dialysate proportioning with reverse osmosis-treated tap water
Authors: Doern G V , Brogden B E , DiFederico J D , Earls J E , Quinn M L
Published: January 2020

Two methods for estimating the quantity of microorganisms present in hemodialysis fluid, a blood agar surface-spread plate method and a total-count water tester device impregnated with modified standard plate count agar (Millipore Corp., Bedford, Mass.), were evaluated. Both methods exhibited comparable precision; however, colony counts obtained with the total-count water tester were consistently and unacceptably low. The need for routine quantitative microbiological monitoring of hemodialysis fluids such as that recommended by the American Public Health Association was not supported by the results of this study. Such testing was not of value in predicting untoward reactions for patients undergoing hemodialysis, nor did quantitative testing of hemodialysis fluids identify the buildup of potentially hazardous levels of contamination within hemodialysis systems. Finally, the kinds of organisms found in hemodialysis systems, i.e., gram-negative water-borne bacilli, were elucidated.
Antibody Capture Immunoassay Detection of Japanese Encephalitis Virus Immunoglobulin M and G Antibodies in Cerebrospinal Fluid
Authors: Burke Donald S. , Nisalak Ananda , Ussery Michael A.
Published: January 2020

Immunoglobulin M (IgM) and IgG antibodies to Japanese encephalitis virus (JEV) were detected in acute-phase cerebrospinal fluid (CSF) specimens from patients with acute encephalitis by using a solid-phase radioimmunoassay of the antibody capture type. Of 12 patients with JEV infections subsequently proven by hemagglutination inhibition serology, 11 had JEV IgM antibodies, as measured by antibody capture radioimmunoassay, in the first CSF specimen (geometric mean titer, 1:2,500) compared with 0 of 8 patients with acute encephalitis proven not to be due to JEV. Specific IgM anti-JEV activity (units per microgram) was greater in CSF than in parallel serum specimens in all 11 positive cases by more than fourfold on the average (range, 1.4 to 13). Among seven patients with broadly reactive hemagglutination inhibition seroresponses typical of persons previously exposed to other flaviviruses, six had high levels of JEV IgG antibodies (as measured by antibody capture radioimmunoassay) in their acute-phase CSF (geometric mean titer, 1:26,000), whereas in five patients experiencing their first flavivirus infection, JEV IgG antibodies measured by antibody capture radio-immunoassay were either absent (one patient) or weakly reactive (four patients; geometric mean titer, 1:3,200). Specific IgG anti-JEV activity was greater in CSF than in parallel serum specimens in eight of the nine positive cases measured (range, 1.3- to 24-fold). The antibody capture solid-phase immunoassay approach is well suited for detecting specific antibody activity in CSF.
Concentrated gram stain smears prepared with a cytospin centrifuge
Authors: Shanholtzer C J , Schaper P J , Peterson L R
Published: January 2020

A Cytospin slide centrifuge was used to concentrate 0.05- to 0.5-ml samples of cerebrospinal and other body fluids for Gram stain. Trials with cerebrospinal fluid containing known numbers of microorganisms indicated that the Cytospin increased the sensitivity of cerebrospinal fluid Gram stains by up to 2 logs compared with unconcentrated and conventional centrifuge smears. Cytospin-concentrated smears were prospectively compared with unconcentrated Gram-stained smears and bacteriological culture results for 80 clinical body fluid specimens. Bacteria were seen in unconcentrated smears of 9 of the 16 (56%) fluids which were infected, whereas Cytospin smears of 12 of the 16 (75%) showed bacteria. Cytospin smears revealed more bacteria and demonstrated better leukocyte morphology than did unconcentrated or conventionally centrifuged samples of small volumes of infected body fluids, allowing early diagnosis of infection.
Enhancement of recovery of Legionella pneumophila from contaminated respiratory tract specimens by heat
Authors: Edelstein P H , Snitzer J B , Bridge J A
Published: January 2020

Heating of Legionella pneumophila and other Legionella spp. was studied to determine whether this technique could be used as a selective technique with contaminated clinical specimens. Studies of 13 different strains of Legionella spp. showed heterogeneous heat survival; heating at 60 degrees C for 1 to 2 min did not affect the survival of the majority of strains. Heating of four Pseudomonas aeruginosa strains at 60 degrees C for 2 min reduced bacterial counts by 98% or greater. Enterococci were heat tolerant, with virtually no inhibition under the same conditions. No inoculum effect was noted for any of the organisms tested. Heating of eight contaminated clinical specimens before plating on buffered charcoal-yeast extract medium reduced the numbers of contaminants on most plates but increased by only one the number of specimens yielding L. pneumophila. Plating the same specimens on selective media with or without heat pretreatment yielded L. pneumophila in every case. Heating of clinical specimens at 60 degrees C for 1 to 2 min before plating may occasionally increase the recovery of L. pneumophila from contaminated specimens, but this technique should not be generally used.
New passive hemagglutination assay kit that uses hemagglutinin-sensitized erythrocytes for detection of rubella antibodies
Authors: Coates S R , Madsen R D , Rippe D F
Published: January 2020

A new passive hemagglutination assay for the detection of antibodies to rubella virus hemagglutinin (PHAST-Rubella) was compared with the hemagglutination inhibition (HI) test and another passive hemagglutination test that uses a soluble rubella virus antigen (SA-PHA). When the immune responses of vaccinated individuals were monitored, similar rises in antibody titer were detected by HI or PHAST-Rubella, whereas the rise in titer detected by SA-PHA was delayed. Early-phase vaccine-induced immunoglobulin M antibody analyzed by sucrose gradient fractionation was detected to the same degree by HI and PHAST-Rubella, but early-phase immunoglobulin G antibody reacted more strongly in the HI test. When acute and convalescent serum pairs from rubella-infected individuals were evaluated, a fourfold rise in titer was detected by PHAST-Rubella and HI in 15 of 15 pairs, whereas SA-PHA, which is not intended for detecting antibody titer rises in acute infections, detected a rise in titer in only 3 of 15 pairs. In studies to determine rubella immune status, testing of 1,078 premarital and random serum specimens resulted in 98.6% agreement among the three methods in identifying rubella antibody-positive and -negative individuals. For the quantitative PHAST-Rubella procedure, a coefficient of correlation of 0.93 was obtained, in comparison with HI, when a panel of 40 characterized sera were tested. These results indicate that PHAST-Rubella reagents can detect rubella antibodies as well as HI reagents and thus may be used as a fast and accurate means of determining rubella immune status and for the quantitation of rubella antibodies.
Detection of helminth ova and larvae in trichrome-stained stool smears
Authors: Wood J C , Friedly G , de la Maza L M
Published: January 2020

The detection and identification of intestinal helminths were studied retrospectively by comparing the Formalin concentration technique with the trichrome-stained smear technique. A total of 3,997 stool samples from 1,570 patients were examined by both methods. Of the 3,997 samples, 31% (1,239 of 3,997) contained helminths or protozoans or both. A total of 11% (434 of 3,997) of the samples representing 14% (221 of 1,570) of the patients were positive for one or more helminth species. A total of 570 separate identifications of helminth ova/larvae were made. Among the helminth ova/larvae identified. 14.6% (83 of 570) were detected only in the trichrome-stained smear, representing 6.3% (14 of 221) of the patients. From these data, it can be concluded that unless a diligent search of the stained smear for helminths is made, a significant number of helminth infections may be missed. It is, therefore, recommended that stained stool smears be used to aid the detection of helminth ova/larvae in conjunction with Formalin concentration. The appearance of the most common helminth ova/larvae in trichrome-stained smears is described, along with specific characteristics that may be used for their identification. In addition, the advantages and disadvantages of the trichrome staining technique for helminth identification are discussed.
Comparison of methods for isolation and enumeration of thermophilic actinomycetes from dust
Authors: Treuhaft M W , Arden Jones M P
Published: January 2020

Thermophilic actinomycetes are the primary sensitizing agents in farmer's lung disease. We compared dilution pour-plate and spread-plate methods for their usefulness in enumerating thermophilic actinomycetes in moldy silage dust and evaluated the ability of a nonquantitative gravity settling technique to recover thermophilic actinomycetes from moldy silage. Spread plates and pour plates yielded similar estimates of total thermophiles. Higher counts were observed on spread plates (P less than 0.05) for Thermoactinomyces candidus, Micropolyspora faeni, and Saccharomonospora viridis. M. faeni and S. viridis were less efficient than T. candidus in breaking through the agar of pour plates to form colonies which could be identified. Coefficients of variability were less than 10% for the two methods. The relative proportion of organisms recovered by the settling method correlated well with that recovered on spread plates for M. faeni (r = 0.79), S. viridis (r = 0.88), and Thermomonospora spp. (r = 0.79), but not well for T. candidus (r = 0.28). When sophisticated air-sampling equipment is not available, dilution spread plates of dust washings provide a reproducible method for enumerating a broad range of thermophilic actinomycetes of interest. The gravity settling method is a simple, rapid alternative when isolation is all that is required.
Comparison of two methods for bacteriocin typing of Serratia marcescens
Authors: Lai P S , Ngeow Y F , Puthucheary S D , Wang C W
Published: January 2020

Two methods of bacteriocin susceptibility typing for Serratia marcescens were compared. A total of 80 epidemiologically unrelated isolates from patients in a single hospital were typed by the cross-streaking method and the mitomycin C-induced (spotting) method. The cross-streaking method was found to be more discriminatory than the spotting method. Using the cross-streaking method, it was possible to differentiate 50 bacteriocin groups out of the 80 isolates, whereas only 31 groups could be obtained with the spotting method. The reproducibility and percentage typability of the cross-streaking method (82.5 and 93.75%, respectively) were found to be as good as, if not better than, those of the spotting method (78.75 and 90.0%, respectively). Other factors, such as lower economic cost, technical simplicity, and the relative ease in the scoring of results, indicate a preference for the cross-streaking method. The findings of this study support the choice of the cross-streaking method for the bacteriocin typing of S. marcescens in epidemiological studies.
Results of the Centers for Disease Control experimental proficiency testing survey for serum alpha-fetoprotein
Authors: Taylor R N , Przybyszewski V A , Gary E
Published: January 2020

An experimental proficiency testing survey for serum alpha-fetoprotein was conducted among 16 cooperating laboratories. Samples of placental cord serum serially diluted in normal adult serum (simulated maternal serum) were assayed. Results were analyzed for qualitative and quantitative relative accuracy, precision on duplicate and nonduplicate (dilution-related) samples, parallelism, and comparability of units. Although some results had wide distribution, relative accuracy improved when results were normalized against a standard. This procedure improved the overall geometric standard deviation among laboratories on quantitative results from 1.300 to 1.088 and compressed the limits for consensus ranges of results to 40% of that of the unnormalized data. No significant differences in actual mean values were noted between international units per milliliter and nanograms per milliliter in measuring alpha-fetoprotein concentrations at the precision obtained in this study. In interpreting whether a sample was "low or normal" or "abnormally high" for alpha-fetoprotein, we observed that an 80% or greater consensus was achieved on only 6 of the 10 survey samples because borderline samples were included in the survey.