bluuebunny/crossref_metadata_2025 huggingface dataset:
Serologic Response of Turkeys to an Agent Associated with Infectious Enteritis (Bluecomb)
Authors: Carson C. A. , Naqi S. A. , Hall C. F.
Published: December 2020

The serologic response of turkey poults to an infectious enteritis (bluecomb disease) agent was analyzed. Serum samples collected from poults on post-inoculation days 3, 7, 14, and 21 were compared to serum from normal poults by electrophoresis and immunoelectrophoresis. Albumin concentrations were decreased whereas alpha and gamma globulins were increased during the disease. Qualitative and quantitative changes occurred in all migration zones.
Immunogenicity of Rabies Virus Inactivated by β-Propiolactone, Acetylethyleneimine, and Ionizing Irradiation
Authors: Wiktor T. J. , Aaslestad H. G. , Kaplan M. M.
Published: December 2020

Ionizing radiation, β-propiolactone, and acetylethyleneimine were compared for their ability as virus-inactivating agents for the preparation of rabies vaccine. Each agent reduced viral infectivity exponentially; ionizing radiation also destroyed viral hemagglutinin. The vaccine prepared by ionizing radiation was equal or superior to that prepared by β-propiolactone in its ability to protect mice from rabies infection. The acetylethyleneimine-treated vaccine was a less potent immunogen.
Mass Purification of Nucleopolyhedrosis Virus Inclusion Bodies in the K-Series Centrifuge
Authors: Breillatt J. P. , Brantley J. N. , Mazzone H. M. , Martignoni M. E. , Franklin J. E. , Anderson N. G.
Published: December 2020

Nucleopolyhedrosis virus inclusion bodies specific for
Hemerocampa pseudotsugata, Neodiprion sertifer, Porthetria dispar
, and
Heliothis zea
have been purified by using a continuous-sample-flow-with-isopycnic-banding centrifuge in quantities up to 6 × 10
13
polyhedral inclusion bodies per day. Continuous-flow methods for S-ρ type purification have been evolved to deal with mass isolation of bioparticles.
Microantiglobulin Test for Detecting
Salmonella typhimurium
Agglutinins
Authors: Williams J. E. , Whittemore A. D.
Published: December 2020

A sensitive antiglobulin (AG) test procedure for the demonstration and experimental study of the agglutinin response of chickens infected orally with
Salmonella typhimurium
is described. A tetrazolium-stained
S. typhimurium
antigen was employed with microagglutination techniques and equipment for the first time in conducting the AG test. Results with the conventional macroscopy tube agglutination test for
S. typhimurium
and the 24-hr microtest were comparable; however, the AG test enhanced titers as much as 16 times, and these persisted at a significant level for as long as 4 months. This study is being extended to other
Salmonella
serotypes and possible field applications of the AG test procedure.
Mechanism of the Inactivation of the Bacteriophage T
1
in Aerosols
Authors: Trouwborst T. , De Jong J. C.
Published: December 2020

The mechanism of inactivation of bacteriophage T
1
in aerosols was studied by using
32
P-labeled phage. During inactivation, viability decreased in parallel with the adsorption of
32
P to the host, showing either that inactivated phage does not adsorb or that the deoxyribonucleic acid (DNA) has left the coat. A
32
P band at the density of free DNA was found when inactivated phage was analyzed in a CsCl gradient.
Evaluation of Two Commercially Available Media for Detection of Bacteremia
Authors: Washington John A.
Published: December 2020

Analysis of the results of 13,162 blood cultures during a 9-month interval has shown that
Pseudomonas aeruginosa
statistically was recovered more frequently from Trypticase soy broth (TSB) than from Thioglycollate-135C and that contaminants, including
Staphylococcus epidermidis
and aerobic and anaerobic
Corynebacterium
species, were isolated with statistically greater frequency from Thioglycollate-135C than from TSB. No other statistically significant differences were found.
Susceptibility of Cheese and Yoghurt Starter Bacteria to Antibiotics
Authors: Cogan T. M.
Published: December 2020

Eight single-strain lactic streptococci, three commercial cheese starters, and six lactic acid bacteria isolated from yoghurt were examined for their susceptibility to penicillin, cloxacillin, tetracycline-hydrochloride and streptomycin. The ranges of the antibiotics causing 50% inhibition of the bacteria were (μg/ml): penicillin, 0.009 to 0.20; cloxacillin, 0.24 to 2.50; tetracycline, 0.09 to 0.60; and streptomycin, 0.35 to 13.0. The average concentrations required to cause 50 and 100% inhibition of the cheese starters were (μg/ml): penicillin, 0.12 and 0.26; cloxacillin, 1.91 and 3.9; tetracycline-hydrochloride, 0.13 and 0.36; and streptomycin, 0.59 and 2.06. All the cocci were about equally susceptible to tetracycline, and all organisms were more resistant to cloxacillin than penicillin. The yoghurt isolates were more resistant to streptomycin and more susceptible to penicillin than the cheese starters. The 2, 3, 5-triphenyltetrazolium chloride test, using
Streptococcus thermophilus
BC as assay organism, does not detect low levels of streptomycin in milk. However, it is useful in detecting cloxacillin residues.
Tapé Fermentation
Authors: Djien Ko Swan
Published: December 2020

Microorganisms isolated from ragi, originally obtained from Indonesia, were selected for their ability to convert steamed glutinous rice into tapé, an Indonesian fermented food. A mixture of
Chlamydomucor oryzae
and
Endomycopsis fibuliger
had good fermentation characteristics. Prepared starters, produced by growing pure cultures on rice and drying them, were as active as pure cultures grown for 4 days on Difco mycological agar slants at 30 C.
Bacteriocin Typing of
Serratia marcescens
Isolates of Known Serotype/-Group
Authors: Traub Walter H.
Published: December 2020

The number of isolates of
Serratia marcescens
that could be typed by sensitivity to bacteriocins was compared with the nature of the serotype/-group of each of the isolates. Ninety-four of 101 isolates (93.1%) could be bacteriocin-typed; this compares with 80 of the isolates (79.2%) that had been serotyped, and with 91 of the isolates (90.1%) that carried determinable O antigens. It is recommended that bacteriocin typing of
S. marcescens
be adopted by reference laboratories, because this technique is simple, inexpensive, and appears to be of somewhat higher epidemiological resolution than classic serological procedures.
Physical State in Which Naphthalene and Bibenzyl are Utilized by Bacteria
Authors: Wodzinski Richard S. , Bertolini Donald
Published: December 2020

The generation times of a strain of
Pseudomonas
grown on a mineral salts medium in the presence of various amounts of naphthalene did not vary with the amount of solid present, and these generation times were the same as the generation time on mineral salts medium containing only dissolved naphthalene. The generation time of a soil isolate grown on mineral salts medium in the presence of 0.5 g of solid bibenzyl per liter was the same as the generation time on a mineral salts medium saturated with bibenzyl. The evidence indicates that naphthalene and bibenzyl are utilized in the dissolved state.
Microbial Utilization of Crude Oil
Authors: Jobson A. , Cook F. D. , Westlake D. W. S.
Published: December 2020

The utilization of two crude oil samples of different quality at 4 and 30 C has been studied by using pure and mixed bacterial cultures obtained by enrichment procedures. Growth, emulsification, and utilization occurred readily at both temperatures. The crude oil residue is increased in specific gravity and readily sediments out of solution. A comparison of the chemical analysis of the oils by liquid and gas-liquid chromatographic procedures before and after growth showed that the
n
-saturate fraction had been preferentially used. Some utilization of the aromatic fraction also occurred. Enrichments obtained with a high-quality crude oil were not as effective in utilizing a lower quality crude oil as sole carbon source as a population enriched on the low-quality crude oil.
Factors Affecting Organic Acid Production by Sourdough (San Francisco) Bacteria
Authors: Ng Henry
Published: December 2020

Previous workers from this laboratory observed considerable variation in the proportions of acetic and lactic acids produced in pure broth culture as compared to consistently high proportions of acetic acid produced in the sourdough and flour suspension systems. In the latter the proportion of acetic acid was always in the range of 20 to 35% of the total, whereas in pure broth culture frequently less than 5% acetic acid was produced. In the natural environment, the sourdough bacteria, tentatively identified as lactobacilli, coexist with a yeast,
Saccharomyces exiguus
, and this study was undertaken to determine whether this yeast or flour ingredients including glucose or other factors were involved in this variable production of acetic acid. The proportion of acetic acid produced in broth culture on maltose, the preferred carbohydrate source, was found to depend almost entirely on the degree of aeration. Essentially anaerobic conditions, as obtained by thorough evacuation and flushing with CO
2
or N
2
, resulted in very low (5% or less) proportions of acetic acid. Aerobic conditions, achieved by continuous shaking in cotton-plugged flasks, yielded high levels (23 to 39% of the total) of acetic acid. Similar effects of aeration were observed with glucose as the substrate, although growth was considerably slower, or in nonsterile flour suspension systems. It is theorized that, under aerobic conditions, the reduced pyridine nucleotides generated in the dissimilation of carbohydrate are oxidized directly by molecular oxygen, thereby becoming unavailable for the reduction of the acetyl phosphate intermediate to ethyl alcohol, the usual product of anaerobic dissimilation of glucose by heterofermentative lactic acid bacteria. Comparative studies with known strains of homo- and heterofermentative lactobacilli showed similar effects of aeration only on the heterofermentative strains, lending additional support to the tentative grouping by previous workers from this laboratory of the sourdough bacteria with the heterofermentative lactobacilli.
L-Asparaginase Production by
Streptomyces griseus
Authors: DeJong Peter J.
Published: December 2020

Streptomyces griseus
ATCC 10137 synthesizes about 1 IU of L-asparaginase/100 ml of a 4% peptone medium. The enzyme has a
p
H optimum of 8.5 which is comparable to that of the L-asparaginase derived from
Escherichia coli
which has antitumor properties.
Survey for Fusaria That Elaborate T-2 Toxin
Authors: Burmeister H. R. , Ellis J. J. , Hesseltine C. W.
Published: December 2020

Of the 136 strains of
Fusarium
examined, T-2 toxin was confirmed by thinlayer chromatography in 13 of the 21 extracts that inhibited either
Rhodotorula rubra
or
Pencillium digitatum
.
Susceptibility of Gnotobiotic Swine to
Escherichia coli
Isolated from Nonenteric Human Infections
Authors: Meyer R. C. , Rhoades H. E. , Simon J.
Published: December 2020

Newborn, germfree piglets were susceptible to
Escherichia coli
associated with human, nonenteric infections and should provide a useful model in the study of generalized
E. coli
infections.
Evaluation and Standardization of an Agglutination Test for Human Listeriosis
Authors: Larsen Sandra A. , Jones Wallis L.
Published: December 2020

Human sera from patients with culturally confirmed listeriosis were tested for immunoglobulin M (IgM) and immunoglobulin G (IgG) agglutinating antibodies with trypsinized antigens of
Listeria monocytogenes, Streptococcus faecalis
, and
Staphylococcus aureus
. The response of humans to listeria infections is mainly IgM rather than IgG as found in animals. The antigens prepared from
L. monocytogenes
serotypes 1a, 1b, 2, 4b, and 4d were evaluated for specificity with normal sera, sera from patients with various other diseases, and sera from patients with listeriosis. The trypsinized antigens appeared to be specific for listeria antibodies with a cross-reaction rate of from 5.4 to 6%. Cross-reaction with
S. aureus
can be eliminated by absorption of the serum with
S. aureus
. This agglutination technique appears to be applicable for diagnostic testing, but, as with all serological procedures, both acute and convalescent sera should be tested.
Concentration and Purification of Poliovirus by Ultrafiltration and Isopycnic Centrifugation
Authors: Guskey Louis E. , Wolff David A.
Published: December 2020

A method is described by which poliovirus can be rapidly and simply concentrated by the use of a Diaflo XM-50 ultrafilter membrane. Freon-extracted ultrafilter concentrates banded in CsCl provided a 1,724-fold volumetric concentration of poliovirus. During concentration, trypsin-digested cellular material can pass through the ultrafilter membrane, thus providing a versatile means of degrading and eliminating extraneous contaminating proteins. The ultrafilter concentration system is compared with the CsCl cushion system of poliovirus concentration, and both systems are further compared by banding virus and virus capsid material in CsCl by use of isopycnic centrifugation.
Indirect Fluorescent-Antibody and Quantitative Agar-Gel Immunodiffusion Tests for the Serological Diagnosis of Paracoccidioidomycosis
Authors: Restrepo M. Angela , Moncada F. Luz H.
Published: December 2020

The value of various serological tests in the diagnosis of paracoccidioidomycosis was studied. Quantitative agar-gel immunodiffusion and indirect immunofluorescent tests were performed, and the results were compared with those of complement fixation and qualitative agar-gel procedures. The quantitative immunodiffusion procedure was found to serve as the simplest and safest quantitative test that could be performed for evaluation purposes, whereas the indirect fluorescent-antibody test gave nonspecific reactions and, as such, proved unsuitable.
Quantitative Assay of Paravaccinia Virus Based on Enumeration of Inclusion-Containing Cells
Authors: Cambier J. C. , Meek E. S.
Published: December 2020

Bovine paravaccinia virus produces cytoplasmic inclusion bodies on infection of bovine embryonic kidney cells; these were easily recognized when stained with acridine orange or May-Grünwald-Giemsa stain. The inclusions could be shown to contain newly synthesized deoxyribonucleic acid by autoradiography. Counts of inclusion-containing cells decreased when virus suspensions were treated with immune serum before being used to inoculate cell cultures. At 24 hr after infection, the number of cells containing inclusions was directly proportional to the concentration of infectious virus inoculated. These observations provide the basis for a virus assay which is simpler, faster, and more sensitive than the plaque assay.
Use of Gelatinase in the Routine Sampling of Gelatin for
Salmonella
Contamination
Authors: Rose Michael J.
Published: December 2020

Gelatinase added to gelatin enrichment broth suspensions decreased viscosity. Salmonellae were not harmed by enzyme.
Salmonella
isolation procedures can be simplified by eliminating the viscosity problem.
Simplified Fluorescent-Antibody Staining Method for Primary Plate Isolates of Group A Streptococci
Authors: Ederer Grace Mary , Chapman S. Stephen
Published: December 2020

Beta-hemolytic streptococci were identified from primary plates by using a simplified fluorescent-antibody staining method. There was 100% correlation between this method and standard precipitin grouping.
Efficiency of a Transport Medium for the Recovery of Aerobic and Anaerobic Bacteria from Applicator Swabs
Authors: Barry A. L. , Fay G. D. , Sauer R. L.
Published: December 2020

The survival of four aerobic and four anaerobic pathogens was evaluated quantitatively on cotton swabs and calcium alginate swabs stored in dry tubes as compared with swabs stored in Amies Transport Medium without charcoal. Survival of the pathogens was markedly improved when stored in Amies Transport Medium, although there was considerable loss of viability after a few hours of storage.
Removal of Nonspecific Antiproteinases from Serum of Rabbits Hyperimmunized Against
Micrococcus
and
Staphylococcus
Proteinases
Authors: Scherer R. K. , Brown R. W.
Published: December 2020

The naturally occurring (nonspecific) proteinase inhibitor which occurs in the alpha globulin fraction of immune rabbit serum was separated from specific staphylococcal and micrococcal antiproteinases by treatment of the antiserum with 2-ethoxy-6-9-diaminacridine. The 2-ethoxy-6-9-diaminacridine-treated serum could then be used to classify these bacterial proteinases by testing directly on casein agar without prior electrophoresis of the serum.
Problems in the Laboratory Isolation of Simian Hemorrhagic Fever Viruses and Isolation of the Agent Responsible for the Sussex/69 Epizootic
Authors: Myers Martin G. , Vincent Monroe M. , Hensen Sally A. , Tauraso Nicola M.
Published: December 2020

At least six epizootics of simian hemorrhagic fever have occurred at four different primate centers. Although these diseases could easily be transmitted to other monkeys of the
Macaca
species, difficulty has been encountered in isolating the causative virus in cell culture. The results of this study have shown that the isolation of simian hemorrhagic fever virus strains in cell culture is dependent upon the use of a susceptible MA-104 cell strain and that the ability of such strains to support the replication of these viral agents may vary. By using this information we have been able to isolate a viral agent in cell culture from materials derived from the Sussex/69 epizootic.
Cellulolytic Activity of
Thermomonospora curvata:
Nutritional Requirements for Cellulase Production
Authors: Stutzenberger Fred J.
Published: December 2020

The use of a minimal medium for cellulase (C
1
and C
x
) production by
Thermomonospora curvata
increased extracellular C
1
activity (measured by rate of cotton fiber hydrolysis) 11-fold compared with the previously used yeast extract medium. Ground cotton fibers supported the highest cellulase production when compared to other soluble and insoluble carbohydrate sources. Maximal cellulase production occurred at 45 C, slightly less at 55 C, and was insignificant at 65 C (the highest temperature at which cellulase activity appeared stable). At a temperature of 55 C, an optimal
p
H of 8.0, and a cotton fiber concentration of 8 mg/ml, shake cultures of
T. curvata
degraded about 75% of the cellulose during the 10-day period.
Chromatography of Venezuelan Equine Encephalomyelitis Virus Strains on Calcium Phosphate
Authors: Pedersen Carl E. , Slocum Donald R. , Levitt Neil H.
Published: December 2020

Column chromatography of selected Venezuelan equine encephalomyelitis (VEE) viruses on calcium phosphate gel offered a simple and reproducible method for examination of biochemical characteristics and relatedness of strains within the VEE complex. Members of antigenic subgroup I demonstrated a series of elution profiles within a narrow range of 0.22 to 0.25 M phosphate buffer. Members of antigenic subgroups II, III, and IV differed substantially among themselves and viruses of antigenic subgroup I. These differences in elution behavior may contribute to understanding of observed differences in biological behavior and antigenic variation among VEE viruses.
Clostridium botulinum
Type F: Isolation from Venison Jerky
Authors: Midura T. F. , Nygaard G. S. , Wood R. M. , Bodily H. L.
Published: December 2020

A
Clostridium botulinum
type F was isolated from the venison jerky responsible for the only type F botulism outbreak reported in the United States. The isolate differed from the prototype Langeland type F strain in being nonproteolytic.
Control of
Penicillium martensii
Development and Penicillic Acid Production by Atmospheric Gases and Temperatures
Authors: Lillehoj E. B. , Milburn M. S. , Ciegler A.
Published: December 2020

The effects of various gaseous environments and temperatures on development of
Penicillium martensii
NRRL 3612 and production of penicillic acid (PA) were determined. Accumulation of PA in mold-inoculated corn was measured following incubation under air; 20% CO
2
, 20% O
2
, 60% N
2
; 40% CO
2
, 20% O
2
, 40% N
2
; and 60% CO
2
, 20% O
2
, 20% N
2
. Although reduced temperature initially inhibited PA production, at the end of the trial the largest quantity of PA (120 μg/g of corn) was found in air-incubated corn at the lowest test temperature (5 C). Atmospheres enriched with 60% CO
2
reduced PA accumulation below a detectable level at 5 and 10 C after a 4-week incubation period. Spore germination tests were carried out in a liquid growth medium incubated for 16 hr under several test conditions. Germ tube outgrowth at 30 C ranged from 36% in air to 2% in 60% CO
2
, whereas no germination was observed in CO
2
-enriched gases at 10 C. When spore respiration rates were measured in air and O
2
in a liquid growth medium, complete removal of CO
2
from the reaction atmosphere did not reduce O
2
uptake.
Plating medium
p
H as a Factor in Apparent Survival of Sublethally Stressed Yeasts
Authors: Nelson F. Eugene
Published: December 2020

Sublethally stressed cells of 9 of 10 species of yeast were recovered at maximum levels when potato dextrose agar was adjusted to approximately
p
H 8. The optimum for
candida utilis
was at approximately
p
H 10. At
p
H 3.5, as commonly employed with media selective for yeasts and molds, recovery of heat-stressed organisms ranged from essentially the same as at optimum
p
H to levels of 1% or less of the maximum count. The extent to which this may be of practical significance in assessing the microbiological quality of food products remains to be determined.
Improved Dextran Sulfate-Calcium Chloride Method for the Removal of Nonspecific Inhibitors with Modifications for Nonspecific Agglutinin Removal in the Rubella Hemagglutination Inhibition Test
Authors: Nelson D. B. , Quirin E. P. , Inhorn S. L.
Published: December 2020

The dextran sulfate precipitation method for removal of nonspecific inhibitors from sera to be tested in the rubella hemagglutination-inhibition test was modified by shortening the dextran sulfate-serum mixture incubation period from 2 hr to 30 min. A comparative study using both treatment times showed no significant difference in rubella antibody titers. Reducing the treatment time even further also gave comparable results, indicating the select 30-min incubation period is not marginal for undertreatment. It was shown that 41.5% of the 159 serums tested had nonspecific agglutinins at levels from 1:8 to as high as 1:64. In each specimen, all demonstrable nonspecific agglutinin was removed by adsorption with 10%, 0- to 2-day-old chick red blood cells rather than the usually recommended 50% adult chicken erythrocytes.
Susceptibility of Mammalian (Hamster) Cell Culture to Infection with Herpesvirus of Turkeys
Authors: Bedigian H. G. , Sevoian Martin
Published: December 2020

Herpesvirus of turkeys (HVT) infected and replicated in hamster kidney cells as evidenced by cytopathic effects, intranuclear inclusions, and by the presence of herpesvirus particles as seen by electron microscopy. Additional evidence for the presence of HVT in cell cultures was determined by the serum neutralization, complement fixation, and the fluorescent-antibody tests.
Erythritol as a Selective Substrate for the Growth of
Serratia marcescens
Authors: Slotnick Irving J. , Dougherty Mary
Published: December 2020

Serratia marcescens
grew on a basal medium containing 0.5% erythritol as sole source of carbon for growth and energy. Only an occasional strain of
Enterobacter aerogenes
among several members of the family
Enterobacteriaceae
were able to utilize erythritol.
Use of a Tabletop Computer for Antibiotic Assays
Authors: Adams A. P. , Benner E. Jack
Published: December 2020

The increasing need for rapid and accurate assay of antimicrobial agents in body fluids requires technical improvement of skills in these areas. A method for using a tabletop computer to simplify and shorten the statistical analysis of the laboratory data obtained by bioassay with the Olivetti Underwood Programma 101 has been developed so that a secretary or laboratory helper can rapidly develop the standard curves for each day's assays.
Occurrence of Mycobacterium Other than
Mycobacterium tuberculosis
in the Oral Cavity and in Sputum
Authors: Mills Cretyl C.
Published: December 2020

Mycobacteria were cultured from 9% of 424 paired mouthwash-induced sputum specimens. The majority of the organisms were not
Mycobacterium tuberculosis
. Sputum cultures contributed 59% of these isolations.
M. intracellulare
was the species most frequently isolated. The non-
M. tuberculosis
mycobacteria may constitute part of the oral flora of the general population and are not more prevalent in hospitalized patients. Approximately one-third more isolations were made from the patients furnishing two or three pairs of specimens as compared to those patients providing one pair of specimens each. From the paired specimens of 4 of 113 patients, two species of
Mycobacterium
were isolated.
M. intracellulare
was isolated from two of three samples of tap water and from the fingers of 1 of 52 patients.
Recovery of Dengue Viruses from Tissues of Experimentally Infected Rhesus Monkeys
Authors: Marchette Nyven J. , Halstead Scott B. , Nash Donald R. , Stenhouse Andrew C.
Published: December 2020

A tissue explant culture technique for the recovery of dengue virus from experimentally infected monkey tissue is described and compared with tissue culture assay of tissue triturates and co-cultivation of trypsinized cells in cell cultures. The most efficient technique was one in which minced tissue was explanted in co-culture with dengue virus-susceptible LLC-MK2 monkey kidney cells. This technique shows promise of being useful for detection of virus in autopsy material from fatal dengue hemorrhagic fever cases.
Use of Trypsin-Modified Human Erythrocytes in Rubella Hemagglutination-Inhibition Testing
Authors: Quirin E. P. , Nelson D. B. , Inhorn S. L.
Published: December 2020

A method of treating human erythrocytes with trypsin has been modified and found to be an efficient and practical indicator system for the rubella hemagglutination-inhibition test. Both the trypsin-treated human cells and the widely used, newborn chicken erythrocytes were used in comparative testing of 464 selected diagnostic rubella serums. Results with each cell system were essentially the same. The trypsin treatment procedure has been found to be relatively simple, and with our limited testing has not presented any problems with reproducibility. Other advantages include the ready availability of human cells, greater intralaboratory standardization of the test by using the same donors over a long period of time, and elimination of adsorption of test sera with red blood cells.
Microbial Degradation of Crude Oil: Factors Affecting the Dispersion in Sea Water by Mixed and Pure Cultures
Authors: Reisfeld Abraham , Rosenberg Eugene , Gutnick David
Published: December 2020

By means of the enrichment culture technique, a mixed population of microorganisms was obtained which catalyzed the dispersion of crude oil in supplemented sea water. From this enrichment culture, eight pure cultures were isolated and studied. Only one of the isolates (RAG-1) brought about a significant dispersion of crude oil. RAG-1 has been tentatively characterized as a member of the genus
Arthrobacter
. The other seven isolates gave rise to colonies on supplemented oil agar, but were neither able to disperse oil nor to stimulate the dispersion catalyzed by RAG-1. The dispersion of crude oil by either RAG-1 or the enrichment culture was absolutely dependent on exogenous sources of nitrogen and phosphorous and completely inhibited by 10
−2
m
azide. The increase in cell number of RAG-1 was directly proportional to the concentration of crude oil added to the medium over the range 0.05 to 1.0 mg/ml. Within this linear region, 1.0 mg of crude oil yielded 9 × 10
7
cells and approximately 65% of the oil was converted into a nonbenzene extractable form. Accompanying the emulsification was a decrease in the
p
H from 7.6 to 5.0. Acidic conditions, however, were neither necessary nor sufficient for oil dispersion. When sea water was supplemented with 0.029 m
m
K
2
HPO
4
and 3.8 m
m
(NH
4
)
2
SO
4
and inoculated with RAG-1, oil dispersion occurred within 1 day. This dispersion could also be brought about by the supernatant following separation of the cells from the medium. Similarly, the supernatant obtained following growth of RAG-1 on hexadecane was capable of emulsifying crude oil in 60 min.
Microbial Population of Feedlot Waste and Associated Sites
Authors: Rhodes R. A. , Hrubant G. R.
Published: December 2020

A quantitative determination was made every 2 months for a year of the microflora of beef cattle waste and runoff at a medium-sized midwestern feedlot. Counts were obtained for selected groups of organisms in waste taken from paved areas of pens cleaned daily and, therefore, reflect the flora of raw waste. Overall, in terms of viable count per gram dry weight, the feedlot waste contained 10
10
total organisms, 10
9
anaerobes, 10
8
gram-negative bacteria, 10
7
coliforms, 10
6
sporeformers, and 10
5
yeasts, fungi, and streptomycetes. The specific numbers and pattern of these groups of organisms varied only slightly during the study in spite of a wide variation in weather. Data indicate that little microbial growth occurs in the waste as it exists in the feedlot. Runoff from the pens contained the same general population pattern but with greater variation attributable to volume of liquid. Comparable determinations of an associated field disposal area (before and after cropping), stockpiled waste, and elevated dirt areas in the pens indicate that fungi, and especially streptomycetes, are the aerobic organisms most associated with final stabilization of the waste. Yeasts, which are the dominant type of organism in the ensiled corn fed the cattle, do not occur in large numbers in the animal waste. Large ditches receiving runoff and subsurface water from the fields have a population similar to the runoff but with fewer coliforms.
Enterobacteria in Feedlot Waste and Runoff
Authors: Hrubant G. R. , Daugherty R. V. , Rhodes R. A.
Published: December 2020

Samples of beef cattle feedlot waste (FLW), runoff from the pens, and water from a large drainage ditch at the feedlot were examined for
Enterobacteriaceae
. The drainage ditch receives the runoff but contains primarily subsurface drainage from fields on which FLW is spread for disposal. Planting and enrichment techniques with seven different media were used to isolate 553 cultures of enterobacteria. FLW contains about 50 million enterobacteria/g dry weight. More than 90% of these were
Escherichia coli
, none of which were enteropathogenic types as determined with multivalent sera.
Citrobacter
and
Enterobacter cloacae
were other organisms present in moderate numbers. Application of enrichment techniques broadened the spectrum of enterobacteria isolates to include the four
Proteus
spp., both
Providencia
spp.,
Klebsiella, Enterobacter aerogenes, Arizona
, and a single isolate of
Salmonella
(serological group C
2
).
Shigella
was not isolated. The wide spectrum of enterobacteria in FLW may be a hazard if unsterilized waste is refed. Fewer enterobacteria occurred in the runoff and in the drainage ditch; the most numerous species in FLW also were most numerous at these sites. However, neither
Salmonella
nor
Arizona
was isolated from runoff or drainage-ditch waters.
Hydrodynamic Focusing and Electronic Cell-Sizing Techniques
Authors: Shuler M. L. , Aris R. , Tsuchiya H. M.
Published: December 2020

The technique of hydrodynamic focusing, used to improve the resolution of the Coulter counter for the sizing of bacteria, was examined. Latex particles of 0.26 μm
3
to 6.7 μm
3
volume were used to examine the characteristics of the system with and without hydrodynamic focusing. The system then was evaluated for sizing mixed bacterial populations as well as single populations. Possible applications are also discussed.
Comparison of Immunization Methods for Producing Reference Adenovirus Antisera in Horses
Authors: Hierholzer John C. , Gamble William C. , Quist Kenneth D. , Chappell W. Adrian
Published: December 2020

Horses were immunized by a variety of inoculation procedures designed to determine the most efficient method of producing antisera to adenovirus types 25 to 31. The procedures evaluated included immunization by (i) direct intravenous (iv) injection, (ii) iv infusion, (iii) intramuscular (im) injection of virus with and without Freund's incomplete adjuvant, (iv) combined iv and im injections, and (v) combined iv infusion and im injection. The im schedule (no. 3) was superior to the others in terms of immunizing antigen and time required, and hemagglutination-inhibition (HI) and serum-neutralizing (SN) antibody levels produced. HI and SN tests performed with sera before and after heating at 56 C for 30 min showed that heat-inactivation was not necessary for tests with equine antisera.
Dimethylselenide and Dimethyltelluride Formation by a Strain of
Penicillium
Authors: Fleming R. W. , Alexander M.
Published: December 2020

A strain of
Penicillium
which produced dimethylselenide from inorganic selenium compounds was isolated from raw sewage. Sulfate and methionine enhanced growth of the fungus and its production of dimethylselenide in media containing selenite. In solutions containing selenate, methionine inhibited dimethylselenide formation while stimulating proliferation of the fungus. Dimethylselenide was also generated from inorganic selenide. Alkylation did not appear to be a significant mechanism of selenium detoxication by this organism. Dimethyltelluride was also produced by the organism from several tellurium compounds, but this product was synthesized only in the presence of both tellurium and selenium. The yields of dimethylselenide and dimethyltelluride varied with the relative concentrations of selenium and tellurium in the medium.
Effect of Water Activity on Enterotoxin A Production and Growth of
Staphylococcus aureus
Authors: Troller John A.
Published: December 2020

Previous studies indicated that enterotoxin B production by staphylococci was strongly inhibited by slight reductions in water activity (

a
w

) levels. Similar studies reported herein, employing an enterotoxin A-producing strain, indicated that this organism was capable of producing enterotoxin at a much lower

a
w

level than that required for enterotoxin B production. Staphylococcal growth rates were slowed by decreased

a
w

levels in all media tested; however, final cell counts did not drop below 10
8
/ml in the media with the lowest

a
w

levels.
Salmonellae and
Edwardsiella tarda
in Gull Feces: a Source of Contamination in Fish Processing Plants
Authors: Berg R. W. , Anderson A. W.
Published: December 2020

The incidence of
Salmonella
and
Edwardsiella tarda
in gull feces on the Oregon coast was studied to determine the role these birds may have in the contamination of fish products with these organisms. Approximately 2.1 and 0.4% of 521 fecal specimens examined were found to contain
Salmonella
or
E. tarda
, respectively.
Negligible Evaporation Retardation by Oxyethylene Docosanol Under Static Conditions
Authors: Hartman Paul A. , Weber Judith A.
Published: December 2020

Oxyethylene docosanol (OED) retarded evaporation of agar media in petri plates when the plates were used in an air sampler; this confirmed the report of May (2). Flooding of plates with OED solutions or incorporation of OED into agar media, however, did not alter evaporation rates when the plates were stored in incubators or were refrigerated.
Concentration of Reovirus and Adenovirus from Sewage and Effluents by Protamine Sulfate (Salmine) Treatment
Authors: England Beatrice
Published: December 2020

Protamine sulfate was employed to recover reoviruses, adenoviruses, and certain enteroviruses from sewage and treated effluents; 50- to 400-fold concentration of viral content was achieved.
Comparison of Three Techniques for the Total Count of Anaerobes from Intestinal Contents of Pigs
Authors: Vervaeke I. J. , Van Nevel C. J.
Published: December 2020

For the total count of anaerobes from cecal and colon contents of pigs, the roll-tube method of Hungate, the anaerobic ringed-plate technique of Van der Heyde, and incubation of petri dishes in anaerobic jars were compared.
Novel System for Improved Control of Filamentous Microorganisms in Continuous Culture
Authors: Brunner H. , Röhr M.
Published: December 2020

We describe a system devised to overcome the tendency of fungal mycelium grown in continuous cultures to adhere to the walls and hamper the outflow of the fermentation vessel, with resulting difficulties in attainment of true steadystate conditions.
Development and Evaluation of a Simple Latex Agglutination Test for Diagnosis of Tuberculosis
Authors: Cole R. V. , Lazarus A. W. , Hedrick H. G.
Published: December 2020

A simple latex agglutination test (SLAT) based on modifications of existing serodiagnostic techniques, in which commercially available reagents are used, was developed for detection of antibodies against
Mycobacterium tuberculosis
. Tests performed on 553 serum samples from 316 individuals, including 117 bacteriologically confirmed active tuberculosis patients, showed 80% positive titers. Sera from 12 patients with arrested tuberculosis showed 91% positive titers. Nonspecific reactions were noted in 5% of 160 serums from selected normal individuals and patients with diseases other than tuberculosis. The antibodies detected by the SLAT method were found to be relatively stable when exposed to low temperatures, whereas high temperatures reduced the antibody titer considerably. Disodium ethylenediaminetetraacetic acid inactivation of serum complement was found to be satisfactory. No variation of tuberculosis antibody titer was noted in tests on multiple specimens from patients whose conditions were stabilized. However, considerable fluctuation was encountered in antibody titers obtained on recently detected individuals. Data obtained in this study indicate that the modified procedures of the SLAT method could replace the tuberculin skin test for simple screening of tuberculosis in adults.
Introduction of
Pseudomonas aeruginosa
into a Hospital via Vegetables
Authors: Kominos Spyros D. , Copeland Charles E. , Grosiak Barbara , Postic Bosko
Published: December 2020

Pseudomonas aeruginosa
was isolated from tomatoes, radishes, celery, carrots, endive, cabbage, cucumbers, onions, and lettuce obtained from the kitchen of a general hospital, with tomatoes yielding both highest frequencies of isolation and highest counts. Presence of
P. aeruginosa
on the hands of kitchen personnel and cutting boards and knives which they used suggests acquisition of the organism through contact with these vegetables. It is estimated that a patient consuming an average portion of tomato salad might ingest as many as 5 � 10
3
colony-forming units of
P. aeruginosa
. Pyocine types of
P. aeruginosa
isolated from clinical specimens were frequently identical to those recovered from vegetables, thus implicating tomatoes and other vegetables as an important source and vehicle by which
P. aeruginosa
colonizes the intestinal tract of patients.
Enterococci in Insects
Authors: Martin Jonathan D. , Mundt J. Orvin
Published: December 2020

Enterococci were obtained from 213 of 403 insects cultured during a 14-month period, in numbers from 10
3
to 3 � 10
7
/g of insect. Insects were taken only from nonurban, wild, and cultivated fields and woods. In species of insects carrying them, enterococci were not always present in every individual cultured, and often more than one species of enterococcus occurred within a species. Enterococci were obtained from certain insects taken in the field during the dormant season, suggesting their role as overwintering agents. They were generally present in species feeding on nectar, succulent plant parts, and on and ir forest litter, but not from insects feeding on less succulent leaves and stems.
Streptococcus faecalis
was recovered from 32%,
Streptococcus faecium
from 22.4%, and
Streptococcus faecium
var.
casseliflavus
from 43.5% of members of the 37 taxa of insects.
S. faecalis
and
S. faecium
var.
casseliflavus
exhibit a high percent of conformity to the properties published for them. The heterogeneity in properties of
S. faecium
is similar to that found for the species taken from plants. Many fail to grow in broth at 45 C or in broth containing 6.5% NaCl; 50% of the cultures ferment both melezitose and melibiose, and a few ferment neither sugar. The remainder ferment melibiose only. Failure to reduce methylene blue in milk by
S. faecalis
and
S. faecium
is correlated with the inability to ferment lactose. More than 93% of the cultures of
S. faecalis
digest casein in milk from the top downward, following the production of a soft, flowing curd. Because this property is not characteristic of
S. faecalis
taken from humans, the reaction in litmus milk is suggested as a means of differentiation between cultures of remote and innocent origin in nature and recent, human pollution.
Assessment of the Sanitary Effectiveness of Holding Temperatures on Beef Cooked at Low Temperature
Authors: Brown David F. , Twedt Robert M.
Published: December 2020

Beef cubes cooked at low temperature were surface inoculated and incubated at 43.3 through 53.3 C to establish temperature limits for growth of staphylococci, salmonellae, and
Clostridium perfringens
. A greater than 99% reduction in staphylococci was achieved after 6 hr at 48.8 C, of salmonellae at 51.1 C, and of
C. perfringens
at 53.3 C. There were no survivors of a mixed inoculum of
Staphylococcus aureus, Salmonella enteritidis
, and
C. perfringens
after 12 hr at 51.1 C.
Standardization and Quantitation of Immunofluorescence in the Rabies Fluorescent-Antibody Test
Authors: Trimarchi C. V. , Debbie J. G.
Published: December 2020

The standardization and quantitation of immunofluorescence with a Farrand microphotometer in the rabies fluorescent-antibody technique were determined. The system is useful in maintaining the quality of examinations for rabies in a public health laboratory since quantitation of reagent, equipment performance, and specificity of reaction can be evaluated. An analysis of the results demonstrates the high degree of reproducibility and the accuracy of the techniques described.
Isolation of Vi Antigen and a Simple Method for Its Measurement
Authors: Wong K. H. , Feeley John C.
Published: December 2020

Vi antigen was purified from saline extract of
Citrobacter
strain 5396/38 by enzymatic digestion, concentration with ethanol, and precipitation with hexadecyltrimethylammonium bromide. The Vi antigen prepared by this method was 18 and 230 times more protective in mice than two other preparations isolated by an earlier method utilizing acid hydrolysis. A sensitive and specific method of electroimmunodiffusion was described for measurement of Vi antigen.
Relative Chlorine Resistance of Poliovirus I and Coliphages f2 and T
2
in Water
Authors: Shah Prafull C. , McCamish Joan
Published: December 2020

Phage f2 is markedly more resistant to chlorine in water than either poliovirus or coliphage T
2
. Its potential use as an indicator of viral pollution is suggested.
Stability of a Modified, Live Panleucopenia Virus Stored in Liquid Phase
Authors: Poole G. M.
Published: December 2020

It has been shown that a modified, live panleucopenia virus is quite stable when stored in the medium in which it was produced.
Determination of Antibody to Pneumococcal Polysaccharides with Chromic Chloride-Treated Human Red Blood Cells and Indirect Hemagglutination
Authors: Ammann Arthur J. , Pelger Robert J.
Published: December 2020

A method is described for the quantitation of serum antibody to type-specific pneumococcal polysaccharide. The method uses highly purified pneumococcal polysaccharide coated onto human O+ red blood cells by the chromic chloride technique. Each of 14 pneumococcal polysaccharide types was individually coated onto red blood cells and used to determine the antibody response following primary immunization. The method was found to be sensitive, detecting antibody titer increases of several hundred to a thousand-fold. The presence of high preimmunization antibody titers did not obscure the detection of antibody titer increases. The method detected antibody of both the immunoglobulin M and immunoglobulin G class when quantitated after ultracentrifugation and sucrose density gradient separation. By using serum samples obtained from volunteers immunized with a single pneumococcal polysaccharide, the method was standardized resulting in an ability to compare samples taken at different times and obtained from different sources. The method appears to be simple, reproducible, and inexpensive and can be utilized to determine the antibody response following immunization in large population studies.
Identification of T-2 Toxin in Moldy Corn Associated with a Lethal Toxicosis in Dairy Cattle
Authors: Hsu Ih-Chang , Smalley E. B. , Strong F. M. , Ribelin William E.
Published: December 2020

Over a 5-month period during the winter of 1970-71, 20% of the lactating Holstein cows in a Wisconsin dairy herd died after prolonged ingestion of a diet containing 60% moldy corn infested with
Fusarium tricinctum
(2 � 10
5
propagules per g of moldy corn). Ethyl acetate extracts of the ground dried corn induced severe dermal reactions when applied to the skin of shaved 60-g albino rats and killed four of five 100-g rats that were force fed 1 ml in 2 ml of pure corn oil. T-2 toxin (3-hydroxy-4, 15-diacetoxy-8-[3-methylbutyryloxy]-12, 13-epoxy-Δ
9
-trichothecene) at concentrations of 2 mg per kg of dry corn was identified in purified extracts of the moldy corn by means of gas-liquid chromatography and mass spectrometry. This concentration of T-2 toxin in the moldy feed and the nature of the toxic effects observed strongly suggest a major causal relationship.
Detection of Coronavirus 229E Antibody by Indirect Hemagglutination
Authors: Kaye Harold S. , Ong Suat Bee , Dowdle Walter R.
Published: December 2020

Tannic-acid treated sheep erythrocytes (fresh or glutaraldehyde preserved) were sensitized with 229E antigens from human embryonic lung (RU-1) cell cultures. Indirect hemagglutination (IHA) antigen titers in 229E-infected cell cultures paralleled virus infectivity and complement fixation (CF) antigen titers. The identity of the IHA antigen was confirmed by testing extracts from inoculated and control cell cultures for ability to inhibit IHA. Also, significant increases in IHA antibody were demonstrated with acute and convalescent serum pairs from patients with proven 229E infections. A comparison of IHA, neutralization and CF titers for 229E antibodies was made on human sera drawn from different populations. The IHA and neutralization results were in agreement on 93% of the 129 sera found to be positive by at least one of three tests. The number of antibody titers detected by the CF test was insufficient to permit comparison. Hyperimmune sera from animals immunized with OC 43 did not react with 229E by IHA. Also no increase in IHA antibody was demonstrated with acute and convalescent serum pairs from patients with seroconversions to OC 43. These findings suggest that the IHA test provides (i) a rapid and sensitive method for serodiagnosis of 229E infections and (ii) a simple and inexpensive method for seroepidemiological studies.
Efficacy of a Fluorescent-Antibody Procedure for Identifying
Bacillus cereus
in Foods
Authors: Kim H. U. , Goepfert J. M.
Published: December 2020

One hundred and seventeen strains of
Bacillus
were examined by the fluorescent-antibody technique by using the globulin fraction of serum prepared against spores of
B. cereus
T. All but one strain of the 59
B. cereus
tested fluoresced at the exosporium surface. Fluorescent staining of
B. anthracis, B. thuringiensis
, and
B. mycoides
was also observed. Absorption of the globulin fraction with
B. anthracis
and
B. mycoides
resulted in the elimination of staining of these organisms. Absorption with
B. thuringiensis
ATCC 10792 removed antibodies reacting with 6 of the strains of
B. thuringiensis
tested. Absorption with
B. thuringiensis
var.
galleriae
removed antibodies against
B. cereus
to such a degree that the globulin fraction was unusable.