bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of a Newly Developed Latex Agglutination Test and an Immunodiffusion Test in the Diagnosis of Systemic Candidiasis
Authors: Stickle David , Kaufman Leo , Blumer Sharon O. , McLaughlin David W.
Published: December 2020

A newly developed latex agglutination (LA) test and a modified immunodiffusion (ID) test were evaluated. The antigen used was a homogenate of
Candida albicans
. A total of 167 antisera were employed in the evaluation. They included 36 sera from clinically well persons; 78 from patients with various clinical forms of candidiasis; 52 from patients with proven cases of aspergillosis, blastomycosis, coccidioidomycosis, cryptococcosis, histoplasmosis, nocardiosis, paracoccidioidomycosis, sporotrichosis, and tuberculosis; and one serum from a patient with toruloposis. Use of the LA test in conjunction with the ID test permitted the detection of more than 90% of 43 proven candidiasis cases. Of all the heterologous cases and normal human sera tested, LA reactions were noted with 3 of 10 cryptococcosis case specimens, 1 of 9 tuberculosis case specimens, and with the torulopsemia case serum. In contrast, the only heterologous serum reactive in the ID test was that from the patient with torulopsemia.
Torulopsis glabrata
and
C. albicans
antisera gave identical reactions in LA and ID tests with
T. glabrata
or
C. albicans
antigens. ID tests with selected antigens, however, permitted differentiation of rabbit and human
T. glabrata
antibody from that of
C. albicans
antibody. Six different precipitins were recognized with the
C. albicans
antigens. The occurrence of multiple precipitin lines and high LA titers was suggestive of severe candidiasis. The LA test, in contrast to the ID test, appeared to have prognostic value. Together, the LA and ID tests provided a simple, rapid, and accurate means of detecting and monitoring infections by species of
Candida
.
Concentration and Purification of Influenza Virus on Insoluble Polyelectrolytes
Authors: Wallis Craig , Homma Akira , Melnick Joseph L.
Published: December 2020

A method for rapid concentration and purification of influenza virus by adsorption on and elution from an insoluble polyelectrolyte is described. To accomplish this task, influenza virus had to be rendered stable at
p
H 4 to 5, since viruses adsorb to the polyelectrolyte more efficiently at this
p
H range. A precipitate which forms in influenza harvests under acid conditions in the cold can be removed by ammonium sulfate at a concentration which traps the precipitate but not the virus. Thus, ammonium sulfate-treated influenza virus in allantoic fluid could be readily concentrated on the polyelectrolyte. Elution yielded a virus concentrate essentially free of nonviral proteins.
Identification and Quantitation of the Components of Polyvalent Inactivated Influenza Virus Vaccines by Immunodiffusion
Authors: Myers Martin G. , Tauraso Nicola M.
Published: December 2020

One of the basic problems in the standardization of inactivated polyvalent influenza virus vaccines has been the determination of the relative potency of the individual strain components. The chicken cell agglutination test measures reliably the total hemagglutinin content of these vaccines. With immunodiffusion techniques, it is now possible to quantitate each strain component of polyvalent vaccines. Routine application of these techniques would serve as an interim procedure to assess antigenic potency of individual strain components of commercial vaccines until improved tests are developed.
Susceptibility of Phytopathogenic Bacteria to Wheat Purothionins In Vitro
Authors: De Caleya R. Fernandez , Gonzalez-Pascual Blanca , García-Olmedo F. , Carbonero Pilar
Published: December 2020

Purothionins are basic polypeptides with antimicrobial properties that are present in the endosperm of wheat and other cereal species. Susceptibility to wheat purothionins among phytopathogenic bacteria of the genera
Pseudomonas, Xanthomonas, Agrobacterium, Erwinia
, and
Corynebacterium
has been investigated. Sensitive strains have been found in all of these genera except
Agrobacterium
(the only strain of
A. tumefaciens
available proved to be resistant). Minimal inhibitory concentrations (MIC) with partially purified crude purothionins ranged from 1 μg/ml for
C. sepedonicum
(C.5) to 540 μg/ml for
E. amylovora
(E.3). Minimal bactericidal concentrations (MBC) were not higher than twice the MIC value, except for
C. poinsettiae
(C.4) (MBC/MIC = 8). Purothionins α and β, obtained by carboxymethyl-cellulose column chromatography, were tested against
P. solanacearum
(P.2) and
X. phaseoli
(X.2); α purothionin was more active than β against X.2, and β more active than α against P.2. This suggests a relationship between polypeptide sequence and specificity of action.
Improved Hemagglutination Test for Identifying Type A Strains of
Pasteurella multocida
Authors: Carter G. R.
Published: December 2020

A simple, improved, indirect hemagglutination test is described for the recognition of Type A strains of
Pasteurella multocida
. It involves the treatment of mucoid cultures with testicular hyaluronidase. Hydrolysis of the capsular hyaluronic acid presumably releases the specific antigen for adsorption to erythrocytes.
Common Antigenic Determinant in a Rumen Organism and in Salmonellae Containing the Antigen O4
Authors: Sharpe M. Elisabeth , Reiter B.
Published: December 2020

Nineteen of 28 strains of rumen organisms isolated from a cow on a high roughage diet and identified morphologically as butyrivibrios, reacted to a low agglutinin titer with salmonella antisera, forming five groups. However only one strain reacted with polyvalent O salmonella antiserum. This strain reacted with O4 factor serum and with antisera to
Salmonella
strains containing the antigen O4, and agglutinin absorption tests showed the presence of an antigen identical to O4. When 16 further strains of butyrivibrio-like rumen organisms isolated from three cows and one steer were examined, one possessed an antigen similar to but not identical with the antigen O9, and two strains reacted with specific O6,7 factor serum but were not examined further. These four strains were presumptively identified by physiological tests as butyrivibrios. The possible site of antigenic stimulation by such organisms is discussed.
Chromogenesis mirabilis in
Streptomyces griseus
Authors: Arai Tadashi , Mikami Yuzuru
Published: December 2020

A number of chromogenic
Streptomyces
, producing diffusible melanoid pigment on complex organic media, fail to form melanin pigment on conventionally used synthetic tyrosine agar. By means of our new melanin formation test, almost all the chromogenic streptomyces can now be detected in chemically defined medium. In contrast to ordinary chromogenic streptomyces, two streptomyces species of the International Streptomyces Project,
S. griseus
ISP 5236 and
S. ornatus
ISP 5307, produce melanin pigment only on synthetic tyrosine agar, without showing chromogenicity on complex organic media. From the results obtained with
S. griseus
ISP 5236 and
S. phaeochromogenes
ISP 5073, it was revealed that melanin formation by
Streptomyces
, in general, is inhibited by L-cysteine present in organic nitrogen sources incorporated into natural media. Most chromogenic species of streptomyces produce a higher level of tyrosinase and rapidly utilize L-cysteine in the culture media which result in the manifestation of good chromogenicity on natural media. Peculiarity of chromogenicity of
S. griseus
and
S. ornatus
might be due to the lower ability to produce tyrosinase and to utilize L-cysteine in the culture medium.
Effects of Some Disinfectants on African Swine Fever Virus
Authors: Stone S. S. , Hess W. R.
Published: December 2020

Ten commercially available disinfectants were tested at high
p
H in 2% sodium hydroxide and low
p
H in 2% acetic acid as inactivants for African swine fever (ASF) in a protein-rich blood-spleen homogenate. As assayed in leukocyte cultures, sodium hydroxide and acetic acid, sodium meta silicate and Roccal did not inactivate ASF virus in 1 hr at 22 to 25 C. Some viricidal activity as assayed in leukocyte cultures was found with Weladol, Triton X-100 Amphyl, pHisoHex, sodium dodecyl sulfate, LpH, Environ, Environ D, and One-Stroke Environ. Of these, the last four appeared to be most promising. When assayed in pigs, only One-Stroke Environ (1/E) was viricidal. Concentrations of 1.0, 0.75, and 0.5 were effective, but, at 0.25%, virus was not inactivated. The minimal time to inactivate ASF virus by 1% 1/E is 60 min. A room contaminated with ASF virus was made safe for pigs after 1 hr by spraying with 1% 1/E. The most active component of 1/E is
o
-phenylphenol. Although another component of 1/E, i.e.,
o
-benzyl-
p
-chlorophenol, also has some activity, the mixture of the active components of 1/E is most effective against ASF virus. One of the soluble antigens associated with ASF virus is destroyed by 1/E.
Characterization of a Heat-Stable Protease of
Pseudomonas fluorescens
P26
Authors: Mayerhofer H. J. , Marshall R. T. , White C. H. , Lu Margaret
Published: December 2020

A heat-stable, extracellular proteolytic enzyme was isolated from
Pseudomonas fluorescens
P26. Brain heart infusion broth (Fisher Scientific Co.),
p
H 7.5, and incubation at 21 C provided the optimal conditions for bacterial growth for enzyme production. The organism had a D value of 2.6 min at 62.8 C (145 F). The enzyme, however, was quite heat-stable, requiring 15 hr at 62.8 C, 8 hr at 71.4 C, and 9 min at 121 C for complete inactivation. Milk, whey, and casein each had a protective effect on the enzyme against heat inactivation. Purification was accomplished by growth of organisms in broth, centrifugation, sterilization by filtration, ammonium sulfate precipitation (55% saturation), dialysis (against six changes of water), and protein separation by passage through a Sephadex G-100 column. Ultracentrifugation revealed a single band with a sedimentation coefficient of 1.51 which suggested a molecular weight of approximately 23,000. As little as 0.2 unit of the purified enzyme caused detectable flavor defects during 30 days of storage at 4 C, and the Hull test for liberation of tyrosine compared favorably in sensitivity with the sensory method in milk.
Duration of Viability and the Growth and Expiration Rates of Group E Streptococci in Soil
Authors: Schmitz J. A. , Olson L. D.
Published: December 2020

In irradiated and nonirradiated feedlot and pasture soils inoculated with group E streptococci, the organism was not recovered 17 days postinoculation from either the irradiated or nonirradiated feedlot soils incubated at 37 C, but survived in the irradiated pasture soils for 24 and 31 days postinoculation. The streptococci survived in irradiated and nonirradiated soils incubated at 4 C for 116 days and in one irradiated feedlot soil for 165 days. The population of streptococci did not increase in either irradiated or nonirradiated soil, and the expiration rate was greater in the soils incubated at 37 and 25 C than at 4 C. With the relatively prolonged duration of viability of group E streptococci in soil at 4 C, it is suggested that soil contaminated with exudate from draining abscesses of infected swine could act as a source of infection during the colder season.
Formalin-inactivated Venezuelan Equine Encephalomyelitis (Trinidad Strain) Vaccine Produced in Rolling-Bottle Cultures of Chicken Embryo Cells
Authors: Cole Francis E. , May Stephen W. , Robinson David M.
Published: December 2020

Formalin-inactivated Venezuelan equine encephalomyelitis vaccine was prepared from virus grown in rolling-bottle cultures of chicken embryo cells. Trinidad strain virus was propagated in these cultures with a maintenance medium consisting of serum-free medium 199 containing 0.25% human serum albumin (USP) and antibiotics. Manipulation of multiplicity of inoculum (0.06 to 0.00006) and maintenance medium volume (100 to 300 ml) resulted in high-titered virus yields and only moderate cell destruction when fluids from infected cultures were harvested at 18 to 24 hr. The virus was inactivated at 37 C by 0.05% Formalin within 8 to 10 hr and with 0.1% Formalin within 6 to 8 hr. Single dose, antigen extinction tests in mice performed with 30 small-scale vaccine lots showed excellent potency at either Formalin concentration with inactivation periods ranging from 24 to 96 hr.
Microtiter Plate Agglutination Test for
Brucella canis
Antibodies
Authors: Damp Suzanne Cutler , Crumrine Martin H. , Lewis George E.
Published: December 2020

A micro-agglutination test for the antibodies to
Brucella canis
produced similar results to those obtained with the standard tube agglutination method in human and canine sera. The micromethod does provide an economical means of screening sera for the presence of antibodies.
Some Properties of Acid Protease from the Thermophilic Fungus,
Penicillium duponti
K1014
Authors: Hashimoto Hikotaka , Iwaasa Takashi , Yokotsuka Tamotsu
Published: December 2020

A purified acid protease from a true thermophilic fungus,
Penicillium duponti
K1014, was most active at pH 2.5 for milk casein and at pH 3.0 for hemoglobin. The enzyme was stable at a pH range of 2.5 to 6.0 at 30 C for 20 h. The acid protease retained full activity after 1 h at 60 C at a pH range between 3.5 and 5.5. At the most stable pH of 4.5, more than 65% of its activity remained after heat treatment for 1 h at 70 C. These thermal properties show the enzyme as a thermophilic protein. The enzyme activity was strongly inhibited by sodium lauryl sulfate and oxidizing reagents such as potassium permanganate and
N
-bromosuccinimide. No inhibition was caused by chelating reagents, potato inhibitor, and those reagents which convert sulfhydryl groups to mercaptides. Reducing reagents showed an activating effect. The enzyme showed the trypsinogen-activating property at an acidic pH range; optimal trypsinogen activation was obtained at a pH of approximately 3.0. The isoelectric point of the enzyme was estimated to be pH 3.89 by disk electrofocusing. By using gel filtration, an approximate value of 41,000 was estimated for the molecular weight.
Use of Technetium (
99m
Tc) as a Bacterial Label in Lung Clearance Studies
Authors: Johanson Waldemar G. , Kennedy Marina G. , Bonte Frederick J.
Published: December 2020

The suitability of technetium (
99m
Tc), a gamma emitter, for labeling of
Diplococcus pneumoniae
in studies of lung bacterial clearance was examined. A killed bacterial slurry with high specific activity was obtained with a ferric ascorbate reducing system. Approximately 5.5% of radioactive counts dissociated from labeled bacteria in 6 h. Rats were exposed to a uniformly mixed aerosol of untagged, viable pneumococci and killed,
99m
Tc-tagged pneumococci. The aerodynamic behavior of labeled and unlabeled pneumococci was similar. Viable bacterial counts and radioactive counts were determined in lung homogenates at intervals following exposure, and rates of bacterial killing and disappearance of radioactive counts were plotted. Radioactive counts did not increase in the liver during the period of observation, suggesting that the decrease in lung radioactivity represents mucociliary clearance and not release of isotope to the systemic circulation. The use of
99m
Tc for bacterial labeling provides advantages of technical simplicity and personnel safety compared to the use of beta-emitting isotopes.
Quantitative Growth of
Naegleria
in Axenic Culture
Authors: O'Dell William D. , Stevens A. R.
Published: December 2020

A strain of
Naegleria gruberi
, isolated from a Vero cell culture and designated TS-1, was axenically cultivated in monolayer and mass aerating suspension culture. Cultural conditions for constant growth parameters and high-exponential cell densities were defined. Serum or other supplemented fractions were found essential in both Trypticase-yeast extract-glucose (TYG) and Casitone (CAS)-based media. Monolayer cultures grown in the CAS medium required lower levels of serum to reach maximum stationary densities of amoebae than cultures grown in the TYG medium. Heat-killed (121 C, 10 min) whole cell and cell lysate bacterial fractions were capable of replacing the serum in both the TYG and CAS media. Heat-killed bacterial fractions provided the same levels of growth as attained with serum in TYG medium, whereas the bacterial lysate supported only minimal growth in the same medium. In the CAS medium, both bacterial fractions resulted in the same level of growth which was equal to that obtained in reduced serum content. Strain TS-1 was established in suspension culture with the CAS medium used in monolayer culture. The addition of sheep red blood cells (RBC) or RBC lysate greatly enhanced growth responses. Further modifications resulted in a final medium for suspension culture consisting of Casitone-yeast extract-glucose-vitamin base, supplemented with serum and RBC lysate. This medium supported growth with a mean generation time of 9 h at 30 C and a stationary phase yield of greater than 5 × 10
6
amoebae per ml.
Laboratory Identification of Clinically Important Aerobic Actinomycetes
Authors: Berd David
Published: December 2020

A battery of morphological, physiological, and biochemical tests, including paper chromatographic analysis of whole cell hydrolysates, was used to study 177 cultures of aerobic actinomycetes. One hundred thirty-five of the 177 were submitted as diagnostic laboratory specimens; of these, 129 were identified as belonging to 1 of 10 genus or species groups. The tests and procedures used were found to be relatively easy to perform and interpret. On the basis of the results, a flow chart was devised to permit the step by step identification of unknown clinical isolates of these organisms.
Abolition of Swarming of
Proteus
by
p
-Nitrophenyl Glycerin: Application to Blood Agar Media
Authors: Williams Fred D.
Published: December 2020

Comparative plate counts were made of
Staphylococcus aureus
and
Streptococcus pyogenes
growing on blood agar supplemented with individual chemicals to abolish the swarming of
Proteus
. B-phenylethanol, sodium azide, and
p
-nitrophenyl glycerin (PNPG) were used as anti-swarm agents. Each anti-swarm agent effectively abolished swarming for 24 h, but azide failed to control swarming for longer periods of incubation. In addition, azide displayed growth inhibition towards the staphylococci and streptococci resulting in no hemolysis and reduced viable cell numbers with the streptococci. Phenylethanol showed reduced viable cell numbers with the streptococci and unreliable hemolytic reactions. At 0.1 to 0.3 mM, PNPG proved to be a superior anti-swarm agent in that it showed no growth inhibition and allowed normal hemolysis, but abolished swarming for extended periods of time. When laboratory strains of
Streptococcus pneumoniae, Klebsiella pneumoniae, Pseudomonas aeruginosa. Listeria monocytogenes
, and
Vibrio cholerae
were screened on a blood agar medium containing 0.1 mm PNPG, they displayed similar growth and hemolytic characteristics to the identical medium without PNPG.
Persistence of Aflatoxin During the Fermentation of Soy Sauce
Authors: Maing Il-Young , Ayres J. C. , Koehler P. E.
Published: December 2020

Aflatoxin was produced by
Aspergillus parasiticus
NRRL 2999 but not by
A. oryzae
during fermentation of soy sauce. Little aflatoxin was degraded within 6 weeks unless
Lactobacillus delbrueckii
also was present.
Aflatoxin Production of Species and Strains of the
Aspergillus flavus
Group Isolated from Field Crops
Authors: Schroeder H. W. , Boller R. A.
Published: December 2020

Peanuts, cottonseed, rice, and sorghum from Texas were sampled over a 3-year period. To insure adequate isolation of alfatoxin-producing species of fungi, low-quality lots were sampled at a rate greater than their respective proportional representation. Aflatoxins were found each year in peanut and cottonseed and were found in 2 of 3 years in rice and sorghum. Aflatoxins were detected in all four crops. The
Aspergillus flavus
group was much more prevalent in peanut and rice than in cottonseed and sorghum. Of the isolates of the
A. flavus
group, 96% from peanuts, 79% from cottonseed, 49% from sorghum, and 35% from rice produced aflatoxins. The average toxin production of isolates from rice was much less than that from peanuts, cottonseed, or sorghum. More than 90% of all isolates of the
A. flavus
group were identified as the species
A. flavus. A. parasiticus
was isolated from all four crops. Only
A. parasiticus
produced aflatoxin G.
Intrawell Absorption of Antisera in a Template Thin-Film Gel Diffusion Method
Authors: Auernheimer Arthur H. , Zimmerman Robert A.
Published: December 2020

This report describes a method for in situ absorption of antisera within the template wells used in thin-film microgel diffusion. The intrawell absorption of antisera offers several advantages over previously reported techniques for detecting the presence of given antigens in biological preparations. The procedure is time saving, antigens are conserved, optimum antigen-antibody ratios are easily determined, and tests of several different absorbing antigens can be made on a single plate.
Proteolytic Enzyme Preparation from
Pseudomonas fragi
: Its Action on Pig Muscle
Authors: Tarrant P. J. V. , Jenkins Nadine , Pearson A. M. , Dutson T. R.
Published: December 2020

An extracellular preparation from
Pseudomonas fragi
with proteolytic enzyme activity was isolated, and its action on meat proteins and meat protein ultrastructure was studied. First, a suitable growth medium for proteolytic enzyme production was determined, and a method for partial purification of the proteolytically active fraction was developed. The enzyme preparation displayed optimal proteolytic activity at neutral pH and 35 C. Proteolytic activity was irreversibly lost by mild heat treatment. The enzyme preparation was tested for its ability to hydrolyze isolated pig muscle proteins. Myofibrillar protein was rapidly degraded, G-actin and myosin were broken down at a slower rate, and the sarcoplasmic proteins were least susceptible to hydrolysis. Electron micrographs of pork muscle showed that the proteolytic enzyme preparation caused a complete loss of dense material from the Z line. Similarities are discussed between the action of
P. fragi
extracellular proteolytic enzyme(s) on meat and normal bacterial spoilage of meat.
Microbial Penetration Through Three Types of Double Wrappers for Sterile Packs
Authors: Standard Paul G. , Mallison G. F. , Mackel Don C.
Published: December 2020

Microbial penetration of sterile packs was studied by using double-wrap (two layers each) muslin, single-wrap (two layers) muslin inner covering with single-wrap (one layer) two-way crepe paper outer covering, and single-wrap (two layers) muslin inner covering with single-layer BAR-BAC wrappers to wrap 20 gauze sponges (2 by 2 in.). These packs were stored on open shelves of a central sterile supply department of a hospital and processed for sterility at weekly intervals. Microorganisms penetrated the double-wrap muslin as early as 28 days, the single-wrap muslin and single-wrap two-way crepe paper combination in 77 days, and the single-wrap muslin and single-layer BAR-BAC combination in 63 days.
Biomagnification of
p, p
′-DDT and Methoxychlor by Bacteria
Authors: Johnson B. Thomas , Kennedy Jack O.
Published: December 2020

Aerobacter aerogenes
and
Bacillus subtilis
accumulated
p, p
′-DDT and methoxychlor directly from water. Uptake of both
14
C-labeled organochlorine insecticides was rapid; 80 to 90% of the 24-h residues were reached within 30 min. Total cellular residues varied linearly with concentrations of DDT and methoxychlor in water ranging from 0.5 to 5.0 μg/liter. The residue magnification factors from water were between 1,400- to 4,300-fold, but were independent of insecticide concentrations in water. When the insecticide-exposed microbial cells were washed with pesticide-free water, DDT residues were 45% in
A. aerogenes
and 30% in
B. subtilis
, whereas the methoxychlor level decreased nearly 75% in both organisms. Subsequent washing did not further reduce the insecticide residue. Autoclave-killed bacteria also rapidly adsorbed DDT and methoxychlor from water and, in some instances, residues were higher than in the living cells. Molecular polarity and lipid solubility appear to influence the retention of the organochlorine insecticides by bacterial cells.
Cations in Hemolymph and Alimentary Tract Tissues of Healthy and Milky Diseased European Chafer (
Amphimallon majalis
) Larvae
Authors: Steinkraus K. H. , Field C. C. , Kochansky M. C. , Kaegebein M. E. , Tashiro H.
Published: December 2020

A study was made of certain cations present in hemolymph and alimentary tract tissues of healthy and diseased European chafer larvae and the spores of
Bacillus popilliae
collected from diseased hemolymph. The major ions found in the hemolymph, in order of decreasing abundance, were potassium, magnesium, sodium, and calcium. Hemolymph of diseased larvae contained relatively higher concentrations of sodium, potassium, magnesium, iron, and zinc than hemolymph of healthy larvae. Concomitantly, the concentrations of ions were lower in the mid-gut and anterior intestinal tissues of diseased larvae. Only sodium decreased slightly in the diseased tissues of the rectum and rectal sac; other ions remained unchanged or increased. Little or no manganese or copper was detected in the hemolymph or tissues. The major cations of spores of
B. popilliae
were sodium, calcium, and magnesium. Small amounts of potassium, manganese, copper, iron, and zinc were detected in the spores. Based on calcium and dipicolinic acid determinations of the spores, sufficient calcium was found to allow for the formation of calcium dipicolinate in the expected concentrations.
Differential Counting in Mixed Cultures with Coulter Counters
Authors: Drake J. F. , Tsuchiya H. M.
Published: December 2020

A critical comparison of Coulter, viable, and microscope counts for several mixed cultures of microorganisms has been made. This investigation shows that Coulter counting can provide reliable estimates of microbial numbers in mixed cultures. Precautions and limitations of Coulter counting in mixed cultures are discussed.
Evaluation of the Improved Auxotab 1 System for Identifying
Enterobacteriaceae
Authors: Rhoden D. L. , Tomfohrde K. M. , Smith P. B. , Balows A.
Published: December 2020

The improved Auxotab Enteric 1 System is more accurate in identifying
Enterobacteriaceae
than is the original product, and results correlate better with those obtained with conventional tests.
Neisseria gonorrhoeae
Auxotyping: Differentiation of Clinical Isolates Based on Growth Responses on Chemically Defined Media
Authors: Carifo Karen , Catlin B. Wesley
Published: December 2020

A system is described for differentiating clinïcal isolates of
Neisseria gonorrhoeae
based on their growth or absence of growth on a set of 11 chemically defined agar media. The complete medium, NEDA, contains all of the compounds required for gonococcal growth; but isolates differ in their ability to grow on NEDA from which selected compounds are individually omitted. The differential compounds include L-proline, L-arginine, L-ornithine, L-methionine, hypoxanthine, uracil, thiamine, and thiamine pyrophosphate. A distinctive pattern of growth responses on the standard media defines an auxotype. Twenty auxotypes were found among a group of 251 gonococci which were isolated from patients examined in the clinics of one city during a 3-month span of time. Another collection of 74 strains from several different countries yielded two additional auxotypes. The stability of the nutritional requirements on which the auxotyping depends was verified in two ways. Cultures isolated from different anatomic sites of a patient or from sexual partners represented the same auxotype, as did cultures which were repeatedly isolated from cases of presumptive treatment failures. Also, the auxotypes of gonococci remained the same after numerous subcultures. The reproducibility of results and the variety and number of auxotypes indicate the potential value of the auxotyping system as an epidemiological tool.
Direct Immunofluorescence Test for the Diagnosis of Genital Herpesvirus Infections
Authors: Rubin Sally Jo , Wende R. D. , Rawls W. E.
Published: December 2020

Herpetic lesions of the genitalia may be confused clinically with other ulcerative, genital lesions. Direct immunofluorescence (FA) provides a rapid method of diagnosis, and the utility of this method for the diagnosis of genital ulcers was examined. One hundred and ten patients with genital lesions were examined by darkfield for syphilis and by FA and culture for herpes simplex virus (HSV) infections. Satisfactory samples were obtained from 102 patients, of which 81 were clinically suspected cases of HSV. Acetone-fixed slides of scrapings of ulcerative lesions were stained with conjugated antiserum prepared in rabbits against HSV type 2. HSV was isolated from 73% of specimens of suspected herpetic lesions, and 77% of these specimens were positive by FA. Nine percent were positive by FA only and these were not thought to represent false positives. Five percent were positive by culture only. A comparison of clinical diagnoses with laboratory findings revealed that 4% of the cases were misdiagnosed when only the clinical evaluation was considered. The data suggest that the inclusion of a diagnostic FA test for HSV along with the darkfield examination may be useful for differentiating the etiological agents of ulcerative, genital lesions.
Evaluation of Passive Hemagglutination, Solid-Phase Radioimmunoassay, and Immunoelectroosmophoresis for the Detection of Hepatitis B Antigen
Authors: Peterson D. A. , Froesner G. G. , Deinhardt F. W.
Published: December 2020

Sensitivity and specificity of passive hemagglutination (RCA), solid phase radioimmunoassay (RIA), and immunoelectroosmophoresis (IEOP) were compared under experimental and clinical conditions. In dilution experiments with sera containing hepatitis B antigen (HB Ag) of known subtypes, the sensitivity for an
ad
subtype serum was RIA (1), RCA (1/2), IEOP (1/256) and for an
ay
subtype serum RCA (1), RIA (1/8), IEOP (1/128). An evaluation of the National Institutes of Health, Division of Biologics Standards test panel number 2 demonstrated HB Ag in 34 of 60 samples by RIA, in 33 by RCA, and in 25 by IEOP. HB Ag was detected in 57.5% of 200 outpatients with a tentative diagnosis of hepatitis by RIA, in 54% by RCA, and in 42.5% by IEOP. In 1,661 volunteer blood donors, 13 (0.78%) were “positive” for HB Ag by RIA, 11 (0.66%) by RCA, and 3 (0.18%) by IEOP. However, absorption experiments indicated that at least six of the above RIA positive and five of the RCA positive sera exhibited nonspecific positive reactions.
In Vitro Production of
Clostridium perfringens
Enterotoxin and Its Detection by Reversed Passive Hemagglutination
Authors: Uemura T. , Sakaguchi G. , Riemann H. P.
Published: December 2020

The reversed passive hemagglutination (RPHA) test yielded a positive reaction in 2 h with as little as 0.5 ng of purified
Clostridium perfringens
enterotoxin (CPE) per ml as well as with cultures of some
C. perfringens
grown in Duncan-Strong (DS) medium. This method is the most sensitive, the simplest, and the fastest among all reported. The time course of CPE production of
Clostridium perfringens
NCTC 8798 in DS was investigated by RPHA. CPE in culture was detectable at 4 h, increased gradually, reached a maximum at 12 to 14 h, and remained at a high level of 20 μg/ml through 48 h of incubation. CPE synthesized within cells is released easily by sonic disruption of young cultures and by aging the cultures 20 h or more. Heat shock of the cell inoculum was essential for CPE production by
C. perfringens
in DS.
Complement-Fixing Antigens Produced by Varicella-Zoster Virus in Tissue Culture
Authors: Martin M. L. , Palmer E. L.
Published: December 2020

The complement-fixing antigens present in tissue cultures infected with varicella-zoster virus were separated into four components. There were (i) a cell-free soluble antigen, (ii) a cell-associated soluble antigen, (iii) a cell membrane-associated antigen, and (iv) a virion antigen. All four antigens were reactive with sera from patients with varicella or zoster, and about 90% of the total complement-fixing activity was found to be nonvirion associated.
Viability of
Actinomycetales
Stored in Soil
Authors: Pridham T. G. , Lyons A. J. , Phrompatima B.
Published: December 2020

About 1,800
Actinomycetales
stored in soil for up to 20 years were checked for viability. About one-half were viable.
Medium for the Isolation of
Aeromonas hydrophila
Authors: Shotts Emmett B. , Rimler Richard
Published: December 2020

A new differential medium, Rimler-Shotts, was tested with 109 isolates representing 13 genera of bacteria obtained from aquatic environments and animals. This medium was effective in presumptive identification of the strains of
Aeromonas hydrophila
examined, with 94% accuracy. Strains of
Citrobacter
which were hydrogen sulfide-variable could not be separated from
A. hydrophila
. This medium was designed to facilitate diagnosis of
A. hydrophila
infections in animals and humans.
Modified Decarboxylase-Dihydrolase Medium
Authors: Smith Harry L. , Bhat-Fernandes P.
Published: December 2020

A modified base medium for amino acids is described which has advantages over Moeller and Falkow media.
Method for Comparing Concentrations of the Open-Air Factor
Authors: Cox C. S. , Hood A. M. , Baxter Jean
Published: December 2020

It is shown how concentrations of the open-air factor may be compared from day to day; this has not been possible previously.
Selective Medium for the Isolation of
Prototheca
Authors: Pore R. Scott
Published: December 2020

A medium was devised which permitted the selective isolation of
Prototheca
spp. from nature.
Microdilution Antibiotic Susceptibility Test: Examination of Certain Variables
Authors: Tilton R. C. , Lieberman L. , Gerlach E. H.
Published: December 2020

A semiautomated microdilution susceptibility test is described. The effect of certain parameters such as inoculum size, growth media, incubation conditions, and inoculum dispensing systems was studied. Both medium type and inoculum size caused significant variations in the minimum inhibitory concentrations (MIC) of certain antibiotic-organism combinations. No effect on MIC was observed as a function of incubator type. Efforts to read a reproducible MIC value in less than 12 h failed. A commercially available wire pronged inoculator was determined to be inaccurate and unsafe. Disposable dropper pipettes proved to be economical, accurate, and precise. Although a standard method for microdilution antibiotic susceptibility testing is not proposed, data are presented which show that future attempts at standardized procedures are mandatory if inter- and intralaboratory reliability is desired.
Effects of Changes in Feed Level, Starvation, and Level of Feed After Starvation Upon the Concentration of Rumen Protozoa in the Ovine
Authors: Potter E. L. , Dehority B. A.
Published: December 2020

Four rumen fistulated sheep were used in five experiments to investigate the effect of feed level upon the concentration of rumen ciliate protozoa. The sheep were fed once daily 650 g of a pelleted diet composed of corn cobs, 45%; alfalfa meal, 35%; oats, 12.5%; cane molasses, 5%; urea, 0.4%; and vitamins and minerals, 2%. The concentration of protozoa reached minimum and maximum values at 5 and 22.5 h after feeding, respectively. Thus, to estimate apparent generation rates, concentrations of protozoa were determined at 5 and 20 h postfeeding. Apparent generation rate/h = natural log of ([concentration of protozoa at 20 h divided by concentration at 5 h] divided by the time interval, [T20 to T5]). Alteration of the feed to protozoa ratio by starvation and by changing the level of feed (200 to 900 g/day) showed that as the ratio of feed to protozoa increased, generation rate increased. Measurements of liquid turnover rates in the rumen showed that turnover rate decreased as feed level decreased. Turnover rate was near zero when the sheep were starved. Small quantities of soluble substrates, added directly to the rumen of starved sheep, maintained the protozoal population when rumen turnover was minimal. Furthermore, as rumen turnover rate increased with increased levels of feed, the effect of substrate on maintaining the protozoal population was negated. Thus, at high feed levels, turnover rate may be the dominant factor controlling the establishment and concentration of protozoa in the rumen.
Prasinons A and B: Potent Insecticides from
Streptomyces prasinus
Authors: Box S. J. , Cole M. , Yeoman G. H.
Published: December 2020

Two metabolites which have high activity against sheep blowfly larvae (
Lucilia sericata
and
L. cuprina
) were found to be produced by
Streptomyces prasinus
NCIB 10719. These substances were isolated from culture filtrate by solvent extraction and chromatography and named prasinons A and B. Fermentation factors affecting the formation of these substances are described together with their physical, chemical, and biological properties.
Pure Culture Studies of
Erwinia carotovora
with 3,5-Diiodo-4-Hydroxybenzonitrile
Authors: Hsu JeMin C. , Camper N. D.
Published: December 2020

Interactions of ioxynil (3,5-diiodo-4-hydroxybenzonitrile) with a pure culture of
Erwinia carotovora
grown in a glucose-simple salts medium were studied. Growth of
E. carotovora
was inhibited by ioxynil and, to a lesser extent, by its acid form at 25 and 50 μg/ml. Growth was not inhibited by the amide or ester forms of ioxynil or
p
-hydroxybenzonitrile at the same concentrations.
E. carotovora
could be trained to grow in 50 μg or higher concentrations of ioxynil per ml by serial transfers of the organism through increasing ioxynil concentrations. No degradation or detoxification of ioxynil was detected. Toxicity tests indicated that, in the adapted culture, cell-free supernatant fluid remained toxic to a nonadapted culture. Adaptation of
E. carotovora
resulted in a lengthened lag phase, a decreased growth rate, and very few adverse effects on the total population. The adapted resistant culture retained this characteristic only when ioxynil was present. Adaptation was demonstrated to be a physiological variation, not a selection of a mutant or of preexisting resistant cells. Ioxynil slightly stimulated the respiration rate of
E. carotovora
and moderately inhibited that of an adapted culture. Because the respiration rate of an adapted culture in the absence of ioxynil surpassed that of a parent culture still in the presence of ioxynil, a competition of two alternate routes of electron transport is implied. These data support the conclusion that an alternate growth mechanism is involved in the adaptation mechanism.
Micromanipulator for Yeast Genetic Studies
Authors: Sherman Fred
Published: December 2020

An inexpensive mechanical micromanipulator, designed primarily for separating yeast ascospores, can be assembled from commercially available components and without extensive custom machining.
Urease Activity of Enterobacteriaceae: Which Medium to Choose
Authors: Vuye A. , Pijck J.
Published: December 2020

Detection and intensity of urease activity in enterobacteriaceae greatly varies as a function of the media or techniques used, or both. A comparative investigation on several solid and liquid media led us to the following conclusions. (i) Detection of
Proteus
spp. can be adequately performed with the highly selective solid medium described by Cook (1948), as well as with the different liquid media described (Stuart standard and rapid media; Elek medium). (ii) Detection of
Klebsiella
should be based upon urease production on solid media with low buffer capacity (Christensen, 1946). (iii) For the identification of
Yersinia
, either the solid Christensen urea agar or the rapid Elek technique give optimal results.
Serological Grouping of Hemolytic Streptococci by Counter-Immunoelectrophoresis
Authors: Edwards Earl A. , Larson George L.
Published: December 2020

The counter-immunoelectrophoresis (CIE) method of grouping streptococci was more sensitive than the capillary precipitin method. The precipitate was easier to read, and the test was simple to perform and required fewer reagents. An autoclave-Pronase-B extraction procedure is described and was found superior to either acid, Pronase-B, or the autoclave extraction procedures for recovering groupable polysaccharide from different strains of streptococcal groups A, B, C, D, F, and E. Data obtained from over 400 strains indicate that the sensitivity of the CIE and a more efficient extraction of groupable polysaccharide provides a simple method for rapid diagnosis of streptococcal infections.
Virus Particles from Conidia of
Penicillium
Species
Authors: Sansing G. A. , Detroy R. W. , Freer S. N. , Hesseltine C. W.
Published: December 2020

Virus particles and their component double-stranded ribonucleic acid (dsRNA) have been isolated from conidia and mycelia of certain
Penicillium
species. The conidia and mycelia of
P. stoloniferum
NRRL 5267 contained 75 and 85 μg of dsRNA/g (dry weight), respectively. Of the total dsRNA released from NRRL 5267 conidia, 10% was nonencapsulated. Conidia of
P. brevi-compactum
NRRL 5260 and
P. chrysogenum
Q-176 contained 2 and 120 μg of dsRNA/g (dry weight), respectively, whereas mycelium from the two species contained 3 and 95 μg of dsRNA/g (dry weight), respectively. No viruses were isolated from conidia or mycelia of
P. stoloniferum
NRRL 859. A method is described for disruption of both conidia and mycelia. The technique facilitates the isolation and characterization of fungal viruses and their component dsRNA and also potentiates surveying of fungal isolates for the presence of virus.
Evaluation of Micro Complement Fixation Tests for Antibodies Against Group A Streptococcal M and M-Associated Antigens in Rabbit and Human Sera
Authors: Beachey Edwin H. , Ofek Itzhak , Cunningham Madeleine , Bisno Alan
Published: December 2020

Variables involved in micro complement fixation (CF) tests for type-specific (TSM) and non-type-specific (NTSM) antibodies against preparations of streptococcal M protein were studied. Sera of rabbits immunized with purified M protein which contained high titers of anti-TSM and low titers of anti-NTSM antibodies reacted type specifically in the CF tests when relatively low concentrations of M protein were employed. In contrast to these artificially induced TSM antibody responses, the sera of rheumatic fever patients demonstrated elevated CF antibody titers (1:80 to 1:320) in the presence of both high and low concentrations of M antigen. The CF test cannot distinguish TSM and NTSM antibodies when the latter predominate. The CF test can be employed with confidence for the detection of NTSM antibodies, provided that the test sera are known to lack type-specific antibodies against the M protein used in the test.
Alternative Procedure to Screening a Large Number of Plates for a Low Number of Mutants
Authors: Westhoff Dennis C.
Published: December 2020

An apparatus is described in which tygon tubing replaces the use of petri dishes in the screening of a large volume of agar for an expected low number of mutants.
Inactivation of Encephalomyocarditis Virus in Aerosols: Fate of Virus Protein and Ribonucleic Acid
Authors: De Jong J. C. , Harmsen M. , Trouwborst T. , Winkler K. C.
Published: December 2020

After aerosolization at relative humidities of 50% or lower, encephalomyocarditis virus is rapidly inactivated. In this process the protein coat of the virion is damaged. This appears as a loss of hemagglutination activity and loss of affinity for hemagglutination inhibiting antibodies. The ribonucleic acid of the virus retains its infectivity but it becomes susceptible to ribonuclease. It sediments in sucrose gradients when centrifuged at high speed with the same velocity as free infectious ribonucleic acid extracted with phenol from intact encephalomyocarditis virus.
Evaluation and Modifications of Media for Enumeration of
Clostridium perfringens
Authors: Hauschild A. H. W. , Hilsheimer R.
Published: December 2020

The suitability of the Shahidi-Ferguson perfringens, TSC (tryptose-sulfite-cycloserine), and oleandomycin-polymyxin-sulfadiazine perfringens agars for presumptive enumeration of
Clostridium perfringens
was tested. Of these, the TSC agar was the most satisfactory. The TSC agar method was improved by eliminating the egg yolk and using pour plates. The modified method allowed quantitative recoveries of each of 71
C. perfringens
strains tested and is recommended. For confirmation of
C. perfringens
, the nitrite test in nitrate motility agar was unreliable, particularly after storage of the medium for a few days. In contrast, positive nitrite reactions were obtained consistently when nitrate motility agar was supplemented with glycerol and galactose.
Interaction of pH and NaCl on Enumeration of Heat-Stressed
Staphylococcus aureus
Authors: Smolka Lawrence R. , Nelson F. Eugene , Kelley Lee M.
Published: December 2020

The effect of pH level and NaCl concentrations, alone and in combination, on the enumeration of unstressed and heat-stressed cells of three strains of
Staphylococcus aureus
was determined. A definite narrowing of the optimum pH range for enumeration of both unstressed and heat-stressed cells was observed as the NaCl concentration was increased from 0.0 to 7.5%. Counts of unstressed cells diminished only slightly with increases in NaCl, whereas heat-stressed cells showed a marked sensitivity to NaCl concentrations of 4% and above, regardless of the pH level. Because of this sensitivity to NaCl, recoveries were far poorer than with unstressed cells at NaCl concentrations of 4% and above.
Rapid Determination of the Presence of Enteric Bacteria in Water
Authors: Kenard R. P. , Valentine R. S.
Published: December 2020

A rapid and sensitive method is described for the detection of bacteria in water and various other natural substrates by the isolation of specific bacteriophage. By the addition of large numbers of the organism in question to the sample, the presence of virulent bacteriophage can be demonstrated in as little as 6 to 8 h. Fecal coliform, total coliform, and total coliphage counts were determined for over 150 water samples from several geographical areas over a period of 2 years. Computer analysis of the data shows a high degree of correlation between fecal coliforms and the coliphage present in the samples. With a high correlation coefficient between fecal coliform and coliphage counts, predictions of the fecal coliforms may be made by enumeration of the phage.
Enumeration of Food-Borne
Clostridium perfringens
in Egg Yolk-Free Tryptose-Sulfite-Cycloserine Agar
Authors: Hauschild A. H. W. , Hilsheimer R.
Published: December 2020

The SFP (Shahidi-Ferguson perfringens), TSC (tryptose-sulfite-cycloserine), EY (egg yolk)-free TSC, and OPSP (oleandomycin-polymyxin-sulfadiazine perfringens) agars have been tested for their suitability to enumerate
Clostridium perfringens
in naturally contaminated foods. Complete recoveries of
C. perfringens
were obtained in each of the four media, but only the TSC and EY-free TSC agars were sufficiently selective to ensure subsequent confirmatory tests without interference from facultative anaerobes. Because of some disadvantages associated with the use of egg yolk, EY-free TSC agar is recommended for enumeration of
C. perfringens
in foods. Several conditions for convenient shipment of foods and
C. perfringens
isolates with minimum loss of viability have been tested. The highest viable counts were preserved when foods were mixed 1:1 (wt/vol) with 20% glycerol and kept in a container with dry ice. Isolated
C. perfringens
strains remained viable for at least 2 weeks at ambient temperatures on blood agar slopes with a 2% agar overlay in screw-cap culture tubes.