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S C Edberg

Publications and source records attributed to S C Edberg.

At least 91 records · Page 5Linked to original sources
PubMed1980

Esculin-based medium for isolation and identification of Cryptococcus neoformans.

A simple medium was developed, using esculin as the substrate, for the isolation and identification of Cryptococcus neoformans. C. neoformans produced a brown-black pigment on the medium; all other yeasts produced no pigment or were light yellow. Esculin is beta-glucose-6,7-dihydroxycoumarin. C. neoformans produced pigment because the 6,7-dihydroxycoumarin component of the esculin molecule was converted to a melanin-like pigment. We think the reaction was similar to the conversion of diphenols, aminophenols, and diaminobenzenes to melanin. Laboratory studies with isolates of C. neoformans, C. albidus, C. luteolus, and C. terreus and representatives of the genera Candida, Torulopsis, Geotrichum, and Rhodotorula, plus environmental field studies, demonstrated that over 95% of C. neoformans isolates were correctly identified, whereas all other fungi were excluded. Esculin agar was a sensitive, specific medium for the isolation and identification of C. neoformans. It was inexpensive and had a long storage life.

Cryptococcus↗
PubMed1980

Scanning electron microscopy of moist bacterial strike-through of surgical materials.

Scanning electron microscopy was used to demonstrate the process of moist bacterial strike-through of woven and nonwoven surgical materials. Three woven and three nonwoven materials were challenged with an aqueous suspension of Serratia marcescens. The results of these studies confirmed that relatively new, less than 100 cycles of washing and sterilizing, 270 thread Quarpel treated Pima cotton prevents moist bacterial penetration. However, this same woven material when washed and sterilized more than 100 times allowed bacterial penetration. Nonwoven materials prevented penetration only when they were impregnated with plastic or reinforced with a plastic film. Prevention of moist bacterial strike-through of surgical materials, whether they be woven or nonwoven, is dependent upon the effectiveness of their waterproof quality. In woven materials, we have confirmed our previous findings indicating that loss of waterproof characteristics, which occurs after 75 washing-sterilizing cyclings, leads to permeability and to moist bacterial strike-through, regardless of the weave density. In nonwoven materials, dependable resistance to moist bacterial strike, through was achieved only when all moisture penetration was prevented by reinforcement with waterproof plastic film.

Bacteria↗
PubMed1979

Quality control of the latex-fixation test.

Standardization of the latex-fixation test for the detection of rheumatoid factor may be achieved by the preparation of a standard reference serum. A number of guidelines for the quality control of precision and sensitivity of the test are suggested. In the use of dilution procedures, a 0.1 log10 or a 0.05 log10 difference between tubes is employed. The end point is defined and titer expressed in terms of a final dilution represented by the amount of antigen-antibody added. For statistical purposes all serologic data are geometrically expressed. Commercial kits may be standardized in terms of minimum detectable units and normalized for titer and unit values to enable laboratories to compare results.

Humans↗
PubMed1979

Performance of latex-fixation kits used for serologic diagnosis of rheumatoid factor in rheumatoid arthritis sera.

Ten latex-fixation kits (both slide and tube) were evaluated by use of a reference serum containing 250 IU of rheumatoid factor (Communicable Disease Center). All tests were performed with serial dilution of serum; adjacent tubes differed by a factor of 0.10 log10. Geometric titers, means, standard deviations, and variance analysis were used to evaluate commercial kits. Three levels of variance were applied: (1) 0.18 or less for intralaboratory variation when the same serum is tested with the same kit; (2) 0.18-0.35 when various lots or batches of the same serum were used; (3) 1.0 or less when various commercial kits were tested with the same serum. The sensitivity of each commercial kit was determined by assigning to it a value (the minimum detectable unit) arrived at by dividing the number of units in the standard by the titer obtained. The technic presented could be applicable to other serologic tests, and thus provide a general method for their standardization and quality control.

Arthritis, Rheumatoid↗
PubMed1979

Moist bacterial strike-through of surgical materials: confirmatory tests.

New tests consisting of modifications of the inverted Mason jar test confirm our previously reported studies which showed that woven and nonwoven surgical materials vary greatly in their ability to serve as barriers against moist bacterial strike-through. Among the woven materials, only tightly woven Pima cloth or materials treated with Quarpel waterproofing process or with polythene layer lamination was invariably resistant. However, tight-woven Pima cloth, which had been treated with Quarpel became permeable after 100 washing-sterilizing cycles. Of the nonwoven materials, single-layer nonwoven materials tended to unevenly permeable to moist bacterial strike-through. Only the front and sleeves of nonwoven gowns reinforced with polyethelene layer were invariably resistant to moist contamination.

Antisepsis↗
PubMed1979

Clinical evaluation of the MICRO-ID, API 20E, and conventional media systems for identification of Enterobacteriacea.

MICRO-ID (General Diagnostics, Morris Plains, N.J.) is a new kit system designed for the identification of Enterobacteriaceae in 4 h. It consists of 15 biochemical tests of paper disks. Each test is in its own compartment in a molded plastic tray. Only one reagent need be added to the system (2 drops of 20% KOH, which is added to the Voges-Proskauer test). Based on the pattern of positive and negative biochemical test results, a five-digit octal code number is calculated. An identification is derived from a computer-generated identification manual. A study was conducted to compare three systems-the MICRO-ID 4-h and the API 20E (Analytab Products Inc., Plainview, N.Y.) 18- to 24-h systems and a conventional media system-to measure the ability of each to identify members of the family Enterobacteriaceae. Comparison tables, rather than simple percentage agreement tables, were generated to define the particular strengths and weaknesses of each system and allow the laboratory to best use the data. The MICRO-ID compared quite favorably with conventional media. MICRO-ID yielded incorrect identifications with 1.5% of the isolates tested (API 20E, 4.7% misidentification rate). Half the MICRO-ID misidentifications occurred when the system identified a Citrobacter diversus as a lysine-negative Escherichia coli; all gave one octal number. A direct comparison of the MICRO-ID and API 20E was of limited value because percentage agreements were merely the sums of the errors of each. The ease of inoculation, the requirement for the addition of only one reagent, and the 4-h capability make the MICRO-ID system an extremely attractive development in the field of bacterial identification.

Bacteriological Techniques↗
PubMed1979

Rapid identification of Enterobacteriaceae from blood cultures with the Micro-ID system.

Micro-ID is a new test system designed to identify members of the family Enterobacteriaceae in 4 h. It consists of 15 biochemical tests on reagent-impregnated paper disks; each test is in its own compartment in a molded plastic tray. Based on the pattern of positive and negative biochemical reactions, a five-digit octal code number is calculated. A computer-generated identification manual accompanies the product, and for each octal code listed there is a numerical value that represents the unknown isolate's degree of fit to a typical organism (LFR), a second numerical value that represents its separation from other organisms (PNOR), and a verbal description of the quality of identification. Only one reagent is added to the system. Manufacturer's directions were modified in this laboratory to allow identification from a turbid blood culture bottle within 4 h. Based on 330 routine clinical cultures tested, there was a 96.1% agreement with conventional identification to the genus and species level: 1.2% yielded first two choices possible, with one being the correct choice; 1.2% provided a correct genus, but no species identification; and 1.5% produced an incorrect identification. The Micro-ID is an accurate, facile system for the rapid identification of Enterobacteriaceae from blood cultures.

Bacteriological Techniques↗
PubMed1979

Streptococcus bovis septicemia and carcinoma of the colon.

We prospectively studied patients with Streptococcus bovis septicemia for the presence of gastrointestinal lesions. This study was prompted by our reported findings of the association of fecal carriage of S. bovis with carcinoma of the colon. We studied 29 patients with 30 episodes of S. bovis septicemia. Fifteen completed gastrointestinal evaluations that included colonscopy, surgery, or autopsy. Eight of these had carcinoma of the colon, three had adenomatous polyps of the colon without carcinoma, and two had carcinoma of the esophagus. The 14 patients who did not have complete evaluations included one each with carcinoma of the stomach, gastric lymphoma, and adenomatous polyp of the colon and three with colonic masses not further delineated. Nineteen patients had no gastrointestinal signs or symptoms or stools positive for occult blood at admission. The results of our study suggest that all patients with S. bovis septicemia need aggressive evaluation of the gastrointestinal tract, especially the colon.

Adenocarcinoma↗
PubMed1978

Esculin hydrolysis reaction by Escherichia coli.

The literature contains variable reports concerning the hydrolysis of esculin by members of the family Enterobacteriaceae and particularly Escherichia coli. We examined 113 strains of fresh clinical isolates of E. coli and assessed the ability of colonies in a population to hydrolyze esculin with and without preincubation in inducible substrates at 24, 48, and 72 h. The number of strains capable of fermenting salicin, a sugar with a beta-glucoside linkage like esculin, was studied under the same conditions. A strip test that measured the presence of the constitutive glucosidase was also performed with and without preincubation in inducible substrates. No E. coli strain was able to produce constitutive enzyme; preincubation in esculin and salicin resulted in an induction of the beta-glucosidase. The number of colonies able to hydrolyze esculin increased with time. Only those strains preincubated in esculin or salicin were able to produce a positive constitutive strip test. Because the beta-glucosidase of E. coli is inducible, one should employe, when using growth media, a light inoculum obtained by touching the top of a colony with a bacteriological wire and read the reaction between 18 and 24 h, or perform a rapid strip or spot test.

Benzyl Alcohols↗
PubMed1977

Association of Streptococcus bovis with carcinoma of the colon.

Two patients with colonic adenocarcinoma and Streptococcus bovis endocarditis suggested a possible association between the two. Non-enterococcal Group D streptococci were isolated from fecal cultures of 11 of 105 controls, 35 of 63 patients with carcinoma of the colon, seven of 25 with inflammatory bowel disease, four of 21 with non-colonic neoplasms and five of 37 with other gastrointestinal disorders. All such streptococci examined for lactose fermentation were S. bovis. The prevalence of S. bovis in fecal cultures from patients with carcinoma of the colon was significantly increased (P less than 0.001) as compared to that in controls, and also to all other groups (P less than 0.001). No other group had results significantly different from those of controls (P less than 0.05) although patients with inflammatory bowel disease were more frequently carriers. The carrier state was unrelated to age, hospitalization status, colonic stasis, gastrointestinal bleeding or recent barium-enema examination. The implications of this association are unknown.

Adenocarcinoma↗
PubMed1977

The use of bile - esculin agar for the taxonomic classification of the family Enterobacteriaceae.

Bile-esculin medium has been used for many years for the presumptive identification of group D Streptococcus. The test is based on the ability of a bacterium to grow in the presence of 40% bile and produce esculinase. 2935 strains of Enterobacteriaceae were inoculated onto bile-esculin agar slants and incubated at 35 C. Esculin hydrolysis was determined after 24 and 48 hours. At 24 hours of incubation esculin hydrolysis was limited to the genera Klebsiella, Enterobacter, Serratia, and the species P. vulgaris, P. rettgeri, and C. diversus. Not all strains of these species were positive, however. All other members of the family were negative. At 48 hours of incubation 37% of E. coli gave a positive reaction; all other Enterobacteriaceae which were negative at 24 hours remained negative. Esculin hydrolysis is a valuable test for the taxonomic classification of the family Enterobacteriaceae.

Bacteriological Techniques↗
PubMed1977

Esculin hydrolysis by Enterobacteriaceae.

Literature reports disagree concerning esculin hydrolysis in the family Enterobacteriaceae. A total of 2,490 strains of the family were investigated for esculin hydrolysis by two methods, the esculin spot test and the PathoTec incubation strip, which measures constitutive enzyme, and five growth-supporting methods, which determine both constitutive and inducible enzymes. The five growth-supporting media studied were: Vaughn-Levine, the standard esculin hydrolysis medium (P. R. Edwards and W. H. Ewing, Identification of Enterobacteriaceae, 3rd ed., 1972); Vaughn-Levine without iron; Vaughn-Levine without Andrade's indicator; and bile-esculin medium. Growth media were incubated at 35 degrees C and checked every 24 h for 120 h. On growth media, 0.3% of Escherichia coli were positive in 24 h, 34% in 48 h, and 61% in 120 h. No strains were positive on the "nongrowth" tests. It appeared that the esculin hydrolysis enzyme(s) of E. coli was inducible rather than constitutive. All esculin hydrolyzers, which yielded positive tests on "constitutive tests" and 24-h tests, were limited to the genera Klebsiella, Enterobacter, and Serratia and species of Proteus vulgaris, Proteus rettgeri, and Citrobacter diversus. When used with standardized inoculum size and incubation time, the esculin hydrolysis test is very useful for differentiation within the family Enterobacteriaceae.

Citrobacter↗
PubMed1977

Determination of antibody concentration using a stopped-flow turbidimetric technique.

The aggregation of albumin and anti-albumin is studied during the first seconds of the reaction by measuring the rate of change of the optical density of the mixture. When this rate is plotted against the antigen concentration of a constant serum dilution, bell-shaped curves are obtained. The maxima of these rate curves parallel the maxima of precipitation curves. Thus, the maximum rate establishes the antigen concentration for maximum precipitate. On the basis of these experiments a method for relative quantitation of antibody in sera is proposed. The absolute concentration of precipitating antibody can be obtained by means of an additional one-tube precipitation experiment.

Animals↗
PubMed1976

Pulmonary infection with Allescheria boydii.

Allescheria boydii, the most common fungus isolated from North American maduromycosis, is a well-described pathogen. Reports of its isolation from sites other than the extremities are rare. Only ten cases of pulmonary infection are recorded in the literature. Of these, two are primary infections, and eight are secondary. An eleventh case is reported. Although there are some elements in the patient's history that indicate that this infection is secondary, the authors regard the infection a primary one. A pathologic and microbiologic compendium of all 11 cases is presented.

Aged↗
PubMed1976

Use of sodium polyanethol sulfonate to selectively inhibit aminoglycoside and polymyxin antibiotics in a rapid blood level antibiotic assay.

Sodium polyanethol sulfonate inhibits aminoglycoside and polymyxin classes of antibiotics in direct proportion to its concentration. Aminoglycoside and polymyxin class antibiotics are selectively inactivated; penicillin, including the semisynthetic penicillins, cephalothin, chloramphenicol, clindamycin, tetracycline, erythromycin, and vancomycin are not inhibited. By incorporating sodium polyanethol sulfonate directly into the test medium it is possible, in a 4-h antibiotic blood level assay, to selectively obviate the activity of the aminoglycosides and polymyxins to determine the concentration of other antibiotics present in the same serum sample.

Aminoglycosides↗
PubMed1976

Rapid, colorimetric test for the determination of hippurate hydrolysis by group B Streptococcus.

A colorimetric test for the determination of hippurate hydrolysis was developed. Brain heart infusion broth made with 1% sodium hippurate served as the test medium. Hydrolysis was determined by the addition of two chemical developers, M (rhodamine B) and A (uranium acetate). A dark pink color indicated hydrolysis; no color change indicated no hydrolysis. The method was efficacious in either rapid or overnight incubation. One hundred twenty-five strains of group B, 44 strains of group A, 15 strains of group C, and 10 strains of group G Streptococcus were tested. By using the Lancefield method as the standard, there was 100% agreement with both the colorimetric and ferric chloride tests for hippurate hydrolysis, and 96% agreement with the CAMP test.

Hippurates↗
PubMed1976

Rapid spot test for the determination of esculin hydrolysis.

Esculin hydrolysis is a useful test in the differentiation of both gram-positive and gram-negative bacteria covering a wide spectrum of aerobes, facultative anaerobes, and anaerobes. Commonly utilized methods require a minimum of 18 h of incubation in broth or agar medium and utilize the production of a brown-black compound, due to the combination of ferric ions with the hydrolysis product esculetin, as indicator. A procedure is presented that requires 15 to 30 min for completion and utilizes fluorescence loss as the indicator of hydrolysis. Esculin fluoresces at 366 nm, whereas the hydrolysis product esculetin does not. Over 1,400 strains of gram-positive and gram-negative bacteria were tested. There was 98.4% of correlation between the spot test and esculin broth and 97% correlation with the bile-esculin agar.

Aerobiosis↗