bluuebunny/crossref_metadata_2025 huggingface dataset:
Survival of anaerobic and aerobic bacteria in a nonsupportive gassed transport system
Authors: Chow A W , Cunningham P J , Guze L B
Published: May 2021

Survival of anaerobic and aerobic bacteria in a commercially available, non-supportive, gassed (oxygen-free) transport container (Anaport) was evaluated quantitatively. Saline-suspended obligate anaerobes survived significantly better in the gassed container in aerobic control tubes (P less than 0.025, t test), and counts were virtually unchanged after 8 h of holding. Similarly, initial counts and relative proportions of a mixture of Bacteroides fragilis and Staphylococcus aureus were maintained for 72 h. The value of the gassed transport system was less apparent when microorganisms were suspended in nutrient broth. The major advantage of the gassed transport system appears to be for holding of specimens collected by saline irrigation.
Anaerobes survive in clinical specimens despite delayed processing
Authors: Bartlett J G , Sullivan-Sigler N , Louie T J , Gorbach S L
Published: May 2021

Quantitative cultures were performed on 11 purulent specimens of at least 2 ml from mixed aerobic-anaerobic infections to determine the effect of prolonged exposure to air on the recovery of anaerobes. The specimens were processed immediately and after air exposure for periods of 10 min and 1, 4, and 24 h. There were at total of 37 anaerobic and 36 aerobic strains recovered from these specimens. Of the anaerobes, 26 were isolated with the initial processing and 22 were still present after air exposure for 24 h. The numerical concentrations of anaerobes showed little change with the sequential samplings. Eleven anaerobic strains were not detected in the initial culture but appeared sporadically in subsequent cultures. Using the types of specimens and method of processing employed in this study, most pathogenic anaerobes survived in purulent exudate despite extended periods of air exposure. The major cause of discrepent results with periodic cultures was attributed to vagaries in sampling.
Diagnostic value of indirect hemagglutination in the seroepidemiology of Shigella infections
Authors: Patton C M , Gangarosa E J , Weissman J B , Merson M H , Morris G K
Published: May 2021

To evaluate the usefulness of the indirect hemagglutination (IHA) test in the epidemiological investigation of shigellosis, single serum specimens were tested from 50 patients with Shigella dysenteriae 1 (Shiga bacillus) infections, 103 asymptomatic contacts of these cases, 267 adult and 100 student control, and serum specimens collected during two outbreaks caused by S. sonnei and one outbreak due to S. flexneri 6. In patients with S. dysenteriae 1, 74% demonstrated titers of greater than or equal to 1:40, with 50% showing titers of greater than or equal to 1:160, whereas in the controls 10.4% had titers of greater than or equal to 1:40 and only 0.3% had titers of greater than or equal to 1:160. IHA titers in serum specimens collected from patients with S. sonnei and S. flexneri 6 were too low to be considered diagnostic for individual patients, but were useful in analysis of group results. Groups of ill individuals yielded titers significantly higher than non-ill groups; however, titers from ill groups were usually less than 1:40. The IHA test for S. dysenteriae 1 antibodies serves as a valuable adjunct to the diagnosis of Shiga bacillus dysentery. In our laboratory, an IHA titer of 1:40 or 1:80 is a "borderline positive." Shiga bacillus dysentery is strongly indicated when IHA titers are greater than or equal to 1:60.
Blocking effect of rheumatoid factor and cold agglutinins on complement fixation tests for histoplasmosis
Authors: Johnson J E , Roberts G D
Published: May 2021

The blocking effect of rheumatoid factor (RF) and cold agglutinins (CA) on the detection of complement-fixing (CF) antibodies for Histoplasma capsulatum using a mycelial (histoplasmin) and a yeast antigen was studied. Sera from 213 patients serologically positive for histoplasmosis were screened for the presence of RF or CA. CF antibodies to H. capsulatum in sera containing RF or CA were studied before and after removal of these factors (RF and CA) by treatment with dithiothreitol. Results suggest that RF or CA may interfere with the CF reaction to the yeast antigen of H. capsulatum but not to the mycelial antigen (histoplasmin).
Evaluation of simplified dichotomous schemata for the identification of anaerobic bacteria from clinical material
Authors: Porschen R K , Stalons D R
Published: May 2021

Simplified dichotomous schemata are described for the identification of anaerobic bacteria commonly encountered in clinical material. The procedures used are combinations of routine biochemical tests and techniques that are used to uniformly characterize these organisms. Over 200 anaerobic organisms were used in a three-stage evaluation in which data were compared with those obtained by conventional methods. When there was inconsistency between the biochemical tests described in the presumptive identification schemes and gas-liquid chromatography, additional biochemical tests or reference procedures were used to confirm identification. Strains from the American Type Culture Collection and the Center for Disease Control, as well as recent clinical isolates, were included in this evaluation. The results show the simplified procedures to be useful for the identification of anaerobic isolates from clinical material.
Simple disk-plate method for the biochemical confirmation of pathogenic Neisseria
Authors: Valu J A
Published: May 2021

The carbohydrate fermentation test in cystine trypticase agar (BBL)-tubed medium was compared with a simple method using commercially available carbohydrate impregnated disks on culture inoculated Thayer-Martin medium with and without (vancomycin, colistimethate, and nystatin) inhibitors. There was 100% agreement between the two methods when a limited sample of clinical isolates of Neisseria gonorrhoeae and Nesseria meningitidis were tested.
Electron capture gas chromatography study of the acid and alcohol products of Clostridium septicum and Clostridium chauvoei
Authors: Brooks J B , Selin M J , Alley C C
Published: May 2021

The metabolic products produced by several strains of Clostridium septicum obtained from patients and animals, along with strains of Clostridium chauvoei, were studied in chopped meat glucose medium by electron capture gas-liquid chromatography (EC-GLC). The strains of C. septicum and C. chauvoei were shown to comprise five different metabolic groups. Both the EC-GLC study and the O and H antigenic study performed previously showed that strains of C. septicum comprise a heterogeneous group. One type of metabolic profile was found only in strains of C. chauvoei. The O antigen types and EC-GLC metabolic types of C. septicum correlated fairly well in isolates from cancer patients but not in stock culture and animal isolates.
Unusual Enterobacteriaceae: H2S+ Shigella sonnei, one authentic and one false positive due to contamination with the obligate anaerobe Eubacterium lentum
Authors: Farmer J J , Riddle C F , Stargel M D , Iida H , Aikawa T , Achanzar D , Taylor W I
Published: May 2021

A mixture of Shigella sonnei and Eubacterium lentum produced H2S in triple sugar iron agar; however, neither produced any in pure culture. A second culture of S. sonnei, isolated in Japan, is thought to be the first documented H2S+ Shigella.
Simple Procedure for Detection of
Mycobacterium gordonae
in Water Causing False-Positive Acid-Fast Smears
Authors: Dizon Delia , Mihailescu Cornelia , Bae H. C.
Published: May 2021

A simple procedure for detecting a few cells of
Mycobacterium gordonae
in laboratory water that yielded spurious smear results is described.
Comparison of sodium amylosulfate and sodium polyanetholsulfonate in blood culture media
Authors: Hall M M , Warren E , Ilstrup D M , Washington J A
Published: May 2021

A comparison between sodium polyanetholsulfonate and sodium amylosulfate in unvented vacuum blood culture bottles containing tryptic soy broth was made with 5,800 sets of blood cultures. No statistically significant differences in isolation rates of bacteria were noted.
Plaque assay of Sendai virus in monolayers of a clonal line of porcine kidney cells
Authors: Ito H
Published: May 2021

The MN strain of Sendai virus formed distinct plaques in monolayers of PS-Y15 cells, an established porcine kidney cell line. The plaque-forming ability was neutralized by specific antibody to the virus. A linear relationship was found between the concentration of virus and the number of plaques. The sensitivity of this assay was about equal to that of the in ovo titration. When applied to the serum neutralization test, the end points obtained were comparable to those of the hemagglutination-inhibition and complement-fixation tests.
Prophylactic immunization of humans against rabies by intradermal inoculation of human diploid cell culture vaccine
Authors: Cox J H , Schneider L G
Published: May 2021

The antirabies human diploid cell vaccine produced by 1'Institute Merieux, Lyon, France, was administered intradermally to 35 high-risk volunteers using 0.2-ml amounts and various immunization schedules. Three groups never before vaccinated against rabies developed virus-neutralizing antibodies, the titer of which was dose dependent. A single injection stimulated the formation of antibodies. Four inoculations induced the highest antibody levels and the longest persistence of antibody. The administration of a single intradermal booster inoculation was sufficient, even in the case of low-persisting antibody, to elicit a rapid increase of antibodies to high levels. A primary inoculation course of two injections induced a sufficient antibody level which, in case of exposure, could apparently be rapidly elevated by a 0.2-ml intradermal booster inoculation. Adverse side reactions were observed in 7 of 14 individuals after a 1- or 1.5-year intradermal booster inoculation. We therefore suggest that the intramuscular and subcutaneous routes continue to be used for primary vaccinations and that the highly effective intradermal route be restricted to booster inoculations. This is the first long term study of this vaccine and should be a guideline for the pre-exposure treatment of high-risk personnel.
Three strains of influenza A virus (H3N2): interferon sensitivity in vitro and interferon production in volunteers
Authors: Richman D D , Murphy B R , Baron S , Uhlendorf C
Published: May 2021

Three antigenic variants of the H3N2 subtype of wild-type influenza A virus (representing the years 1968, 1972, and 1974) were examined for their sensitivity to interferon and for their ability to induce local respiratory tract interferon in volunteers. In addition, the time of appearance of symptoms in infected volunteers was correlated with the patterns of virus shedding and interferon production. The sensitivity to interferon and the ability to stimulate nasopharyngeal interferon were similarly high for all three strains. Symptomatic illness, peak virus shedding, and peak interferon response all occurred within a 26-h period. These findings imply that interferon or its inducers theoretically could be protective if applied prophylactically, but would be less efficacious when used therapeutically.
Blood culture technique based on centrifugation: clinical evaluation
Authors: Dorn G L , Burson G G , Haynes J R
Published: May 2021

A total of 1,000 blood samples from patients suspected of having a bacteremia were analyzed concurrently, where possible, by three methods: (i) Trypticase soy broth with sodium polyanethol sulfonate and a CO2 atmosphere: (ii) pour plates with either brain heart infusion agar or Sabouraud dextrose agar; and (iii) centrifugation of the suspected organism in a hypertonic solution. There were 176 positive cultures. The centrifugation technique recovered 73% of the positive cultures. The broth and pour plate techniques recovered 38 and 49%, respectively. The centrifugation technique showed an increased isolation rate for Pseudomonas, fungi, and gram-positive cocci. In general, for each organism the time required for the detection of a positive culture was shortest for the centrifugation technique.
Effect of cetylpyridinium chloride on pathogenic fungi and Nocardia asteroides in sputum
Authors: Phillips B J , Kaplan W
Published: May 2021

The effect of cetylpyridinium chloride (CPC) on pathogenic fungi and Nocardia asteroides was studied. Sputa seeded with each of 11 organisms (Aspergillus flavus; Aspergillus fumigatus, Blastomyces dermatitidis, Candida albicans, Coccidioides immitis, Cryptococcus neoformans, Geotrichum candidum, Histoplasma capsulatum; Nocardia asteroides, Paracoccidioides brasiliensis, and Sporothrix schenckii) were treated with CPC and kept for 2, 5 and 9 days. The CPC reagent used (0.5% CPC and 0.5% sodium chloride) is one the Mycobacteriolgoy Branch at the Center for Disease Control added to sputa before shipping them to laboratories for recovery of mycobacteria. None of the organisms tested survived this treatment, and none was recovered on mycological or mycobacteriological media. Seeded sputa containing these organisms were also tested with a second CPC reagent (0.02% CPC and 0.5% sodium chloride) and held for 2, 5 and 9 days. A few colonies of A. flavus, A. fumigatus, and N. asteroides were recovered from these samples. Neither the morphology of the fungi nor their stainability by the fluorescent antibody method was affected by treatment with the reagent containing 0.5% CPC. However, the background material in smears from the 0.5% CPC-treated samples retained the conjugate, and this made weakly fluorescing organisms more difficult to detect. The 0.5% CPC treatment did not alter the morphology of N. asteroides or its ability to be stained with Kinyoun acid-fast stain.
Modification of the Minitek Miniaturized Differentiation System for characterization of anaerobic bacteria
Authors: Stargel D , Thompson F S , Phillips S E , Lombard G L , Dowell V R
Published: May 2021

The Minitek Miniaturized System (BBL) was modified for characterization of anaerobic bacteria. The modified system and the conventional Center for Disease Control method were used to test a variety of anaerobic bacteria, and results were compared. Tests performed by both techniques were indole and H2S production, esculin hydrolysis, nitrate reduction, and fermentation of glucose, mannitol, lactose, sucrose, maltose, salicin, glycerol, xylose, arabinose, mannose, rhamnose, and trehalose. The manufacturer's recommended procedure for the Minitek system was modified by using a new suspension medium (Lombard-Dowell broth) and an inoculum equivalent to the density of a McFarland no. 5 nephelometer standard. The Minitek results, recorded after 48 h, agreed satisfactorily with the conventional test results, usually recorded after 5 to 7 days of incubation. In the examination of 80 strains representing 22 different species or subspecies of anaerobic bacteria, with 16 biochemical tests performed in triplicate, 93.8% of the Minitek test results agreed with those of the corresponding conventional tests. Only tests for indole, H2S, and nitrate reduction gave less than 90% agreement. It was concluded that the modified Minitek system is a suitable substitute for the more expensive and time-consuming conventional procedure for determining carbohydrate fermentation and esculin hydrolysis by anaerobes. This system, when used in conjunction with other tests, can effectively aid in the definitive identification of commonly isolated anaerobes.
Anaerobic infections in children: a prospective survey
Authors: Thirumoorthi M C , Keen B M , Dajani A S
Published: May 2021

Over an 18-month period, cultures from 95 infants and children yielded 146 anaerobic organisms in 110 clinical specimens. Bacteroides was the most frequently isolated anaerobe, followed by Propionibacterium and Clostridium species. Intra-abdominal sources, soft tissues, and blood were the three major sources (82%) of isolation of anaerobes. Whereas most patients (58%) were over 5 years of age and only 11% were newborns, anaerobic infections constituted a rather uniform proportion of all infections, regardless of sources, in all age groups. Anaerobes accounted for only 2.9% of all positive cultures encountered from the various sources. Rates of recovery of anaerobes from intra-abdominal sources were significantly the highest, and from soft-tissue infections they were significantly the lowest. The anaerobic bacteremias observed were of no clinical significance when Propionibacterium species were isolated; however, recovery of other anaerobes from the blood, and primarily Bacteroides species, was usually associated with clinical disease. Except in blood cultures, anaerobes almost invariably coexisted with facultative bacteria.
Acceleration of tetrazolium reduction by bacteria
Authors: Bartlett R C , Mazens M , Greenfield B
Published: May 2021

Conditions were assessed which would permit more rapid recognition of bacterial growth than has been previously reported using tetrazolium salts. Microtitration trays were used. 2-(p-Iodophenyl)-3(p-nitrophenyl)-5-phenyltetrazolium chloride is rapidly reduced by respiring cells in tissue homogenates but is more toxic than other tetrazoliums when added to growing bacterial cultures. Phenazine methosulfate (PMS), an intermediate electron carrier, potentiates tetrazolium reduction. Growth was readily detected by the addition of these compounds after 3 to 4 h of incubation in Schaedler broth. The final concentration prior to addition to tray wells was 1.0 mg/ml for 2-(p-iodophenyl)-3(p-nitrophenyl)-5-phenyltetrazolium chloride and 0.06 mg/ml for PMS. Addition of 0.5 to 0.8 g of agar per liter of broth enhanced subsequent tetrazolium reduction.
Gingival flora of the dog with special reference to bacteria associated with bites
Authors: Saphir D A , Carter G R
Published: May 2021

Gingival scrapings from dogs were examined to determine their aerobic bacterial flora. Of particular interest was the frequent recovery of three unclassified groups of aerobic gram-negative bacteria, IIj, EF-4, and M-5, previously associated with human dog-bite infections. Although no set pattern was found between the variability and consistency of gingival microbiota as related to age, sex, or breed of dog, a certain characteristic flora can be predicted in the healthy canine gingiva. Members of the following genera were found: Streptococcus, Staphylococcus, Actinomyces, Escherichia, Corynebacterium, Pasteurella, Caryophanon, Mycoplasma, Acinetobacter, Moraxella, Neisseria, Enterobacter, and Bacillus.
Differentiation of Proteus mirabilis by bacteriophage typing and the Dienes reaction
Authors: Hickman F W , Farmer J J
Published: May 2021

A provisional typing schema based on sensitivity to 23 bacteriophages has been established for Proteus mirabilis. Seventy-three bacteriophages were isolated on strains of P. mirabilis (64), P. vulgaris (1), P. morganii (7), and P. rettgeri (1), but those isolated on P. mirabilis were the most useful in differentiating other strains of . mirabilis. From the 73 phages studied, the best 23 were chosen by computer analysis for the provisional system, which was then used to study P. mirabilis infections in a 500-bed general hospital. All patient isolates for 19 months were saved and then compared by bacteriophage typing and the Dienes reaction in a retrospective study. There was evidence for only three instances of cross-infection or -colonization during this time. Bacteriophage typing was very sensitive in differentiating strains, since 200 strains were differentiated into 113 different lysis patterns and 94% were typable. The Dienes reaction was useful at times but often gave reactions that were difficult to read or that changed when the tests were repeated. The bacteriophages described by Schmidt and Jeffries were also evaluated and proved useful in combination with ours. The value of bacteriophage typing was clearly established, and work toward a standardized schema for P. mirabilis should continue.
Immunoperoxidase technique for detection of antibodies to human cytomegalovirus
Authors: Gerna G , McCloud C J , Chambers R W
Published: May 2021

The indirect immunoperoxidase antibody technique (IPA) has been applied to determine immunoglobulin (Ig)G to humans cytomegalovirus (CMV) antibodies in 114 blood donor sera, four cases of congenital cytomegalic inclusion disease, and four cases of acquired CMV infection. The results have been compared with those obtained with the CMV complement fixation (CF) test and indirect fluorescent antibody technique (IFA) for broad spectrum CMV antibody (sigmaAb) detection. IgG antibody has been detected by both CF and IPA. In healthy adult people IPA titers are usually higher than CF titers. In addition, IFA sigmaAb titers are generally higher than CF titers. Some sera negative by CF and IPA are positive at low dilutions by IFA sigmaAb antibody determination, due to the detection of small amounts of IgA or noncomplement-fixing IgG. Nonspecific results seem unlikely, since only nuclear inclusion fluorescence was interpreted as specific, as demonstrated by blocking tests. In acute CMV infection, the IFA sigmaAb and IPA IgG titers are essentially the same, except during the first weeks of infection, when IFA titers are higher and IgM is detectable. No cross-reactivity with other herpes group viruses, herpes simplex and varicella-zoster, was observed. Although some problems of nonspecific staining of cytoplasmic inclusions are shared by both methods, the IPA technique seems to possess the same degree of sensitivity and specificity as the IFA technique, but interpretation is easier and various procedural steps can be delayed without the technical problems associated with fluorescence microscopy.
Use of gum tragacanth overlay, applied at room temperature, in the plaque assay of fish and other animal viruses
Authors: Dobos P
Published: May 2021

Fish cells derived from rainbow trout gonad or Atlantic salmon are sometimes damaged by the relatively high temperature of agar overlay widely used for plaquing animal viruses. This heat-induced cell damage can be avoided by the use of gum tragacanth, which may be applied at room temperature. When the medium was buffered with tris(hydroxymethyl)aminomethane-hydrochloride and NaHCO3, the plaque assay could be performed without the use of a CO2 incubator. Using this method, a number of animal viruses were plaqued on a variety of cell monolayers at different temperatures under atmospheric ocnditions.
Clinical cholera caused by enterotoxigenic Escherichia coli
Authors: Finkelstein R A , Vasil M L , Jones J R , Anderson R A , Barnard T
Published: May 2021

A woman returning from Mexico was hospitalized as an emergency patient with hypovolemic shock due to dirrheal disease of less than 1-day duration. Her clinical course was similar to that of severe cholera--she excreted greater than 60 liters of stool and urine in a 4-day period. The etiological agent was a non-enteropathogenic serotype but enterotoxigenic strain of Escherichia coli (063:NM). The patient responded both agglutinating and antitoxic antibodies against this strain and its enterotoxin. An "enteropathogenic serotype," 0111:B4, was also isolated but this finding had no etiological significance.
Medium-dependent inhibition of Peptostreptococcus anaerobius by sodium polyanetholsulfonate in blood culture media
Authors: Wilkins T D , West S E
Published: May 2021

Of 13 species of anaerobic cocci, Peptostreptococcus anaerobius was the only species tested that was sensitive to 0.1% sodium polyanetholsulfonate (SPS). However, the sensitivity of P. anaerobius to SPS varied according to the media in which the cultures were grown. In supplemented peptone (B-D) and brain heart infusion media, most strain of P. anaerobius were not inhibited by SPS. Gelatin and proteose peptone were the medium components which were protective. The minimal inhibitory concentration of SPS for P. anaerobius was approximately 60-fold higher in media. However, the concentration of SPS required to neutralize the bactericidal properties of human serum was only four fold higher in media containing geltain. In a commerical medium containing SPS (0.03%) and gelatin (1.2%), SPS-sensitive strains of P. anaerobius were not inhibited by SPS, and the bactericdal action of human blood on Escherichia coli C and Serratia marcescens SM 29 was eliminated.
Viral antibody in the cerebrospinal fluid of patients with acute central nervous system infections
Authors: Deibel R , Schryver G D
Published: May 2021

Cerebrospinal fluid (CSF) and sera from 129 patients of a study population of 139 were tested for antibody to herpes simplex, measles,and mumps viruses. Herpes simplex virus antibody was found in three of five patients with laboratory-confirmed herpes simplex infection and in eight patients without serological or virological evidence of current infection with this or other common neurotropic visuses. Eleven of the 139 patients were studied for antibody to lymphocytic choriomeningitis (LCM) virus. Eight of these had laboratory-confirmed LCM infection, and antibody was detected in the CSF of five of them. In one of these five, complement-fixing antibody appeared earlier in the CSF than in the blood. Assay of LCM virus antibody in the CSF may thus indicate infection with LCM virus more rapidly than serological and virological studies. The diagnostic and the possible prognostic significance of herpes simplex visus antibody in CSF remains to be ascertained.
Elimination of bacteriophages from tissue culture serum by affinity chromatography
Authors: Orr H C , Weetall H H , Probst P G , Littlejohn D C , Chu F C , Johnson J B , Petricciani J C
Published: May 2021

Use of immunoadsorbents to remove bacteriophages from tissue culture serum was investigated. Immune globulins from rabbit antiserum prepared against phi V-1 phage were immobilized by covalent linkage to activated porous silica glass derivatives of p-aminoarylamine and to Sepharose-4B. Chromatographic columns of each material were used to filter samples of a fetal bovine serum into which had been introduced 8100 plaque-forming units of the phage per ml. Efficiency of removal was determined by plaque assays of phi V-1 phage recovered in the effluent fluids. Activated but uncoupled matrices nonspecifically removed from 49 to 59% of the phages introduced into the experimental serum. A reduction of 35 to 37% in phage content occurred in the serum after filtration through columns coupled to nonantibody protein. With specific immune globulins attached, the Sepharose-4B matrix reduced the concentration of phage in the serum below a detectable quantity. Noapparent alterations occurred in the growth-promoting property of serum filtered through the Sepharose-4B immunoadsorbent as measured by cloning efficiency of BHK-21, WI-38, and FRhL-2 cells. These experiments serve as a model system for use of immunoadsorbents for selective removal of bacteriophages and perhaps other extraneous microbial agents from tissue culture serum.
Differential identification of Mycobaterium szulgai and other scotochromogenic mycobateria
Authors: Seva-sutter E A , Silcox V A , David H L
Published: May 2021

Strains of scotochromogenic mycobacteria were studied by using numerical taxonomy methods in an attempt to more clearly define Mycobacterium szulgai and to find tests useful in identifying the species. In this study all strains of M. szulgai were strong reducers of nitrate, were slow in hydrolyzing Tween 80, and gave a high semiquantitative catalase reaction. Results obtained indicate that the use of increased pigmentation after 1 h of light exposure at 25 C and that the use of arylsulfatase activity are of questionable diagnostic value in separating the species from other scotochrompgenic mycobacteria.
Analysis of cost and accuracy of alternative strategies for Enterobacteriaceae identification
Authors: Robertson E A , Macks G C , MacLowry J D
Published: May 2021

Analysis of the cost of time and material required for the diagnosis of Enterobacteriacea isolates indicated that a conventional 17-tube (20-test) setup costs $7.98 per isolated identified. Using the API 20E, a similar identification cost $3.02. A conventional 7-tube (10-test) setup cost $3.60, whereas the comparable cost by 30% while increasing the number of isolate identified correctly by 3%. Other strategres using the API 20E or a deoxyribounclease test were also evaluated for cost and accuracy.
Evaluation of the Bacti-Lab streptococci culture systems for selective recovery and identification of group A streptococci
Authors: Freeburg P W , Buckingham J M
Published: May 2021

Twenty-nine lots of Bacti-Lab streptococci culture plates containing nalidixic acid, neomycin, and amphotericin B were inoculated with 25 strains of group A, B, C, F, and G strepotocci, 13 strains of nonstrepotcoccal organisms representative of the throat flora, and 198 fresh clinical thorat specimens to determine the accuracy of the plates in identifying group A streptococci. With the Bacti-Lab test plates 98.87% of the beta-hemolytic streptococcal strains tested produced growth 95.51% yielding more than 50 colonies. Of the nonstreptococcal beta-hemolytic and non-beta-hemolytic organism tested, 79.54% were inhibited by the selective media. When bacitracin disks were used for presumptive identification group A streptococci from clinical thorat specimens, 12.00% false positive and 0.00% false negative results were obtained as measured by the direct flourescent-antibody and Lancefield grouping methods.
Simple Method for Immunofluorescent Identification of Mycoplasma Colonies
Authors: Bradbury Janet M. , Oriel Christine A. , Jordan F. T. W.
Published: May 2021

General purpose rubber stoppers proved to be a simple, rapid, and satisfactory method of transferring mycoplasma colonies from agar to microscope slides for immunofluorescence.
Duodenal isolation of Salmonella typhi by string capsule in acute typhoid fever
Authors: Gilman R H , Hornick R B
Published: May 2021

Three of seven volunteers with acute typhoid fever had Salmonella typhi isolated from the duodenum using a string capsule device. The string capsule device provides a simple method for culturing S. typhi from the duodenal contents. Its possible use in typhoid carriers is discussed.
Improved method for production of attenuated Venezuelan equine encephalomyelitis (TC-83 strain) vaccine
Authors: Cole F E , Pedersen C E , Robinson D M , Eddy G A
Published: May 2021

Primary chicken embryo cell cultures were evaluated a s an alternate cell system for the production of attenuated Venezuelan equine encephalomyelitis (TC-83 strain) vaccine. The TC-83 strain virus was shown to remain stable during 10 serial passages in chicken embryo cell culture with regard to plaque size and morphology, virus yield, potency, and virulence for mice and hamsters.
Use of CO
2
for More Rapid Growth of the
Nocardia
Species
Authors: Boncyk L. H. , Millstein C. H. , Kalter S. S.
Published: May 2021

Growth of the
Nocardia
species is facilitated by use of 10% CO
2
for initial isolation from clinical material or from laboratory stock cultures.
Effect of sonic treatment on pure cultures and aggregates of bacteria
Authors: Robrish S A , Grove S B , Bernstein R S , Marucha P T , Socransky S S , Amdur B
Published: May 2021

Pure cultures of a variety of bacteria were treated with ultrasonic energy using a sonic probe. Fractions of organisms killed at different sonic energies were calculated, and Streptococcus mutans was 600 times more resistant than Fusobacterium nucleatum, the most sensitive organism tested. The effects of sonic treatment on aggregates of bacteria were examined, and the results were interpreted as a model of the events that probably occur during the sonic dispersion of dental plaque.
Laboratory investigation of diarrhea in travelers to Mexico: evaluation of methods for detecting enterotoxigenic Echerichia coli
Authors: Morris G K , Merson M H , Sack D A , Wells J G , Martin W T , Dewitt W E , Feeley J C , Sack R B , Bessudo D M
Published: May 2021

A laboratory investigation was conducted on cultures collected from travelers before, during, and after a trip to Mexico to characterize the etiology of traveler's diarrhea. Four laboratory methods for detecting enterotoxigenicity of Escherichia coli were evaluated: the infant mouse assay, the Chinese hamster ovary (CHO) cell assay, the Y1 adrenal cell assay, and the rabbit ileal loop. Although a number of common enteric pathogens were identified as a cause of traveler's diarrhea, including six serotypes of Salmonella, two serotypes of Shigella, Vibrio parahaemolyticus, Giardia lamblia, and Entamoeba histolytica, enterotoxigenic Escherichia coli was most commonly isolated. Strains were identified that produced only heat-labile enterotoxin (LT), only heat-stable enterotoxin (ST), or both LT and ST. The infant mouse assay yielded results falling into two distinct groups, providing a clear separation of positive and negative cultures. The CHO assay also formed two groups, with positive cultures producing 11% or more of the elongated cells. There was good agreement between the CHO and the Y1 adrenal cell assays for detection of LT. The adrenal cell system for detection of LT was more suitable than the CHO assay for processing large numbers of specimens because of the miniculture modification of this method utilized in this study. The infant mouse method was a simple and reliable method for detecting ST.
Clinical evaluation of the addition of gentamicin to commercially prepared mycological media
Authors: Merz W G , Sandford G , Evans G L
Published: May 2021

A simple procedure is presented whereby an antibiotic solution can be added to prepared agar media for conversion to a selective medium to isolate fungi. Gentamicin solution was deposited onto slants of a variety of previously prepared agar media, allowed to diffuse overnight, and then the slants were inoculated with clinical specimens. Control media without gentamicin included a cycloheximide-chloramphenicol medium (CC), Sabouraud dextrose agar (SDA), and brain heart infusion agar (BHI). Of 75 specimens originating from the respiratory tract, the fungi isolated were predominantly yeast; 35, 39, and 43 were positive on CC, SDA, and SDA with gentamicin, respectively, incubated at 25 C. At 37 C, 32, 34, and 41 positive cultures were obtained with the same media, respectively. The same specimens, inoculated onto BHI with and without gentamicin, yielded 23 and 39 positive cultures, respectively. Of 90 specimens that were either urine, cutaneous, or mucocutaneous, the predominant flora again were yeasts, although on nine occasions dermatophytes were isolated. Positive cultures, 32, 34, and 41, were obtained with CC, SDA, and SDA containing gentamicin, respectively. Bacterial contamination was significantly reduced by the gentamicin, especially on BHI incubated at 37 C. None of the specimens was positive for systemically pathogenic fungi, other than species of Candida, Torulopsis, and Aspergillus. The effectiveness of varying concentrations of gentamicin was investigated by comparing growth of recently isolated bacteria. Of the bacterial isolates, 33% grew on CC, 16% grew on SDA containing gentamicin, 50 mug/ml, and 3% grew on SDA with a gentamicin concentration at 100 mug/ml. With BHI, 3% grew in the presence of 50 mug of gentamicin/ml and less than 1% grew at 100 mug of gentamicin/ml.
Antibody response to Rocky Mountain spotted fever
Authors: Kenyon R H , Canonico P G , Sammons L S , Bagley L R , Pedersen C E
Published: May 2021

Various techniques were compared to determine the most sensitive method for detection of rocky Mountain spotted fever antibody. A radiometabolic technique for detection of Rocky Mountain spotted fever antibody is also described. In infected monkeys, the fluorescent antibody technique yielded the earliest evidence of seroconversion; with some monkeys the microagglutination procedure was equally effective. The fluorescent antibody and microagglutination measurements showed higher titers than those for complement fixation, Weil-Felix, or the radiometabolic techniques.
Procedure for Fluorescent-Antibody Staining of Virus-Infected Cell Cultures in Plastic Plates
Authors: Pursell Alfred R. , Cole John R.
Published: May 2021

Acetone fixation and fluorescent-antibody staining of virus-infected cell cultures were performed in plastic plates. Proper addition of acetone as a fixative did not alter the plastic.
Rapid method for identification of gram-negative, nonfermentative bacilli
Authors: Otto L A , Pickett M J
Published: May 2021

A rapid system (OA), based on oxidative attack of substrates, was developed for identification of gram-negative, nonfermentative bacillia (NFB). One hundred and twelve strains of NFB from 25 species (representing the genera Pseudomonas, Alcaligenes, Acinetobacter, Bordetella, Flavobacterium, Moraxella, and Xanthomonas) were assayed by OA, buffered single substrate, and oxidative/fermentative methods. The 38 substrates consisted of salts of organic acids, nitrogen-containing compounds, alcohols, and carbohydrates. Ninety-four percent of the test strains were identified by the OA method in 24 h, and 99% were identifiable in 48 h. Reproducibility was 99%. Correlation with buffered single substrate was 98% (all substrates) and 90% with the oxidative/fermentative method (carbohydrates only). Biochemical profiles of all strains are presented, as well as tables showing the most useful tests for identification.
Large-scale purification of hepatitis B surface antigen
Authors: Vnek J , Prince A M
Published: May 2021

Hepatitis B surface antigen was concentrated and purified from plasma by two simple steps of purification. In the first step the antigen was purified 24-fold by polyethylene glycol precipitation. An additional 10-fold purification was achieved by batchwise adsorption to hydroxylapatite and subsequent elution with 0.02 M sodium phosphate buffer.
Long-chain fatty acids of Sporothrix (Sporotrichum) schenckii
Authors: Stretton R J , Dart R K
Published: May 2021

A number of strains purporting to belong to the species Sporothrix schenckii were examined for their fatty acid content. The majority of the strains were isolated from cases of sporotrichosis. Two strains were reputedly saprophytic. In all cases except the two saprophytic ones the major fatty acid was a C18 diene. Considerable amounts of palmitic acid and C18 monoene were found in all strains.
Differentiating
Taenia solium
and
Taenia saginata
Infections by Simple Hematoxylin-Eosin Staining and PCR-Restriction Enzyme Analysis
Authors: Mayta H. , Talley A. , Gilman R. H. , Jimenez J. , Verastegui M. , Ruiz M. , Garcia H. H. , Gonzalez A. E.
Published: May 2021

Species-specific identification of human tapeworm infections is important for public health purposes, because prompt identification of
Taenia solium
carriers may prevent further human cysticercosis infections (a major cause of acquired epilepsy). Two practical methods for the differentiation of cestode proglottids, (i) routine embedding, sectioning, and hematoxylin-eosin (HE) staining and (ii) PCR with restriction enzyme analysis (PCR-REA), were tested on samples from 40 individuals infected with
T. solium
(
n
= 34) or
Taenia saginata
(
n
= 6). Microscopic examination of HE staining of sections from 24 cases, in which conserved proglottids were recovered, clearly revealed differences in the number of uterine branches. Distinct restriction patterns for
T. solium
and
T. saginata
were observed when the PCR products containing the ribosomal 5.8S gene plus internal transcribed spacer regions were digested with either
Alu
I,
Dde
I, or
Mbo
I. Both HE histology and PCR-REA are useful techniques for differentiating
T. solium
from
T. saginata
. Importantly, both techniques can be used in zones of endemicity. HE histology is inexpensive and is currently available in most regions of endemicity, and PCR-REA can be performed in most hospital centers already performing PCR without additional equipment or the use of radioactive material.
Differentiation among Members of the
Mycobacterium tuberculosis
Complex by Molecular and Biochemical Features: Evidence for Two Pyrazinamide-Susceptible Subtypes of
M. bovis
Authors: Niemann Stefan , Richter Elvira , Rüsch-Gerdes Sabine
Published: May 2021

The variations in biochemical as well as molecular characteristics among several members of the
Mycobacterium tuberculosis
complex that are not
M. tuberculosis
have been assessed to facilitate an unambiguous species identification. Altogether, 96
M. tuberculosis
complex strains including 52
M. bovis
isolates and 44
M. africanum
isolates were analyzed by spoligotyping. The strains could be clustered into five spoligotype groups. All
M. bovis
isolates showed the typical absence of the spacers 39 to 43 and typical biochemical properties. However, within these strains we found a group of strains that had a spoligotype pattern which is clearly defined by the additional absence of spacers 3 to 16 and that were uncommonly susceptible to pyrazinamide (PZA). This spoligotype pattern has previously been described as being typical for a caprine genotype because of its predominant isolation from sheep and goats. Due to the clinical importance of PZA resistance, we propose two
M. bovis
subtypes:
M. bovis
subtype
bovis
, which is resistant to PZA, and
M. bovis
subtype
caprae
, which is susceptible to PZA. Two additional strains that clustered in group 3 showed biochemical and genetic properties typical for
M. bovis
and were also sensitive to PZA; thus, they may represent a third PZA-susceptible
M. bovis
subtype. The
M. africanum
isolates could be clustered into two spoligotype groups which can be differentiated from
M. bovis
by hybridization to spacers 39 to 43. These groups correspond to the previously described
M. africanum
subtypes I and II and can be clearly distinguished from each other by spoligotyping and resistance to thiophen-2-carboxylic acid hydrazide. Our results demonstrate that spoligotyping is a useful tool for differentiation of
M. bovis
and
M. africanum
. Moreover, we describe two PZA-susceptible
M. bovis
subtypes and describe a method that facilitates an unambiguous differentiation of the two
M. africanum
subtypes.
Identification of
Nocardia
Species by Restriction Endonuclease Analysis of an Amplified Portion of the 16S rRNA Gene
Authors: Conville Patricia S. , Fischer Steven H. , Cartwright Charles P. , Witebsky Frank G.
Published: May 2021

Identification of clinical isolates of
Nocardia
to the species level is important for defining the spectrum of disease produced by each species and for predicting antimicrobial susceptibility. We evaluated the usefulness of PCR amplification of a portion of the
Nocardia
16S rRNA gene and subsequent restriction endonuclease analysis (REA) for species identification. Unique restriction fragment length polymorphism (RFLP) patterns were found for
Nocardia
sp. type strains (except for the
N. asteroides
type strain) and representative isolates of the drug pattern types of
Nocardia asteroides
(except for
N. asteroides
drug pattern type IV, which gave inconsistent amplification). A variant RFLP pattern for
Nocardia nova
was also observed. Twenty-eight clinical isolates were evaluated both by traditional biochemical identification and by amplification and REA of portions of the 16S rRNA gene and the 65-kDa heat shock protein (HSP) gene. There was complete agreement among the three methods on identification of 24 of these isolates. One isolate gave a 16S rRNA RFLP pattern consistent with the biochemical identification but was not identifiable by its HSP gene RFLP patterns. Three isolates gave 16S rRNA RFLP patterns which were inconsistent with the identification obtained by both biochemical tests and HSP gene RFLP; sequence analysis suggested that two of these isolates may belong to undefined species. The PCR and REA technique described appears useful both for the identification of clinical isolates of
Nocardia
and for the detection of new or unusual species.
Recovery of
Candida dubliniensis
from Non-Human Immunodeficiency Virus-Infected Patients in Israel
Authors: Polacheck Itzhack , Strahilevitz Jacob , Sullivan Derek , Donnelly Samantha , Salkin Ira F. , Coleman David C.
Published: May 2021

Candida dubliniensis
is a recently discovered yeast species principally associated with carriage and disease in the oral cavities of human immunodeficiency virus (HIV)-infected individuals. To date the majority of isolates of this species have been identified in Europe and North America. In this study, five
Candida
isolates recovered from separate HIV-negative hospitalized patients in Jerusalem, Israel, were presumptively identified as
C. dubliniensis
on the basis of their dark green coloration when grown on CHROMagar Candida medium. Their identification was confirmed by a variety of techniques, including carbohydrate assimilation profiles, absence of growth at 45°C, positive reaction with
C. dubliniensis
-specific antibodies as determined by indirect immunofluorescence analysis, and positive amplification with
C. dubliniensis
-specific PCR primers. All five strains were shown to be susceptible to a range of antifungal agents, including fluconazole. One of the five isolates was recovered from urine specimens, while the remaining four were recovered from upper respiratory tract and oral samples. While none of the patients was HIV positive, all were receiving broad-spectrum antibacterials at the time isolates of
C. dubliniensis
were obtained from clinical specimens. This study describes the first isolates of
C. dubliniensis
from the Middle East and confirms that this yeast can be associated with carriage and infection in the absence of HIV infection.
Escherichia coli
Serotype O15:K52:H1 as a Uropathogenic Clone
Authors: Prats Guillem , Navarro Ferran , Mirelis Beatriz , Dalmau David , Margall Nuria , Coll Pere , Stell Adam , Johnson James R.
Published: May 2021

To clarify the clinical and bacteriological correlates of urinary-tract infection (UTI) due to
Escherichia coli
O15:K52:H1, during a 1-year surveillance period we prospectively screened all 1,871 significant
E. coli
urine isolates at the Hospital de la Santa Creu i Sant Pau, Barcelona, Spain, for this serotype and assessed the epidemiological features of community-acquired UTI due to
E. coli
O15:K52:H1 versus other
E. coli
serotypes. We also compared the 25 O15:K52:H1 UTI isolates from the present study with 22 O15:K52:H1 isolates from other, diverse geographic locales and with 23 standard control strains (8 strains from the ECOR reference collection and 15 strains of nonpathogenic O:K:H serotypes) with respect to multiple phenotypic and genotypic traits. Although
E. coli
O15:K52:H1 caused only 1.4% of community-acquired
E. coli
UTIs during the surveillance period, these UTIs were more likely to present as pyelonephritis and to occur in younger hosts, with similar risk factors, than were UTIs due to other
E. coli
serotypes. Irrespective of geographic origin,
E. coli
O15:K52:H1 strains exhibited a comparatively restricted repertoire of distinctive virulence factor profiles (typically, they were positive for
papG
allele II,
papA
allele F16, and
aer
and negative for
sfa
,
afa
,
hly
, and
cnf1
), biotypes, ribotypes, and amplotypes, consistent with a common clonal origin. In contrast, their antimicrobial resistance profiles were more extensive and more diverse than those of control strains. These findings indicate that
E. coli
O15:K52:H1 constitutes a broadly distributed and clinically significant uropathogenic clone with fluid antimicrobial resistance capabilities.