bluuebunny/crossref_metadata_2025_split huggingface dataset:
Age and Lung-Histamine
Authors: Trethewie E. R. 
Published: January 2023

Summary
The histamine-content of foetal lungs was found to be negligible. This is in confirmation of earlier work. At birth the histamine-content of the lung is very high, the concentration being greater than that at either 8, 20 or 40 weeks. The total histamine-content of the lung varies little from birth to 8 weeks in spite of increased size of the lung, but after this period the histamine-content increases. The concentration of the lung histamine expressed as a function of the weight of the animal shows a similar distribution to that of concentration expressed as a function of the weight of the lung. The possible significance of variation in the standard deviation and means in the groups studied is discussed.
Persistence of Antigen at the Site of Inoculation of Vaccine Emulsified in Oil
Authors: Herdegen Miriam , Halbert Seymour P. , Mudd Stuart 
Published: January 2023

Summary
A technic was developed for the in vivo quantitative estimation of Shigella paradysenteriae type III (Z) antigen in mice, by utilization of the minimum quantity found necessary to induce an agglutinin response (0.002 μg). This method was used to determine the fate of this antigen in a mineral oil emulsion at the site of subcutaneous inoculation in mice. Active Shigella antigen was recovered from the site of inoculation in mice at periods up to 18 and 24 weeks, depending on the original dose of antigen. There was a gradual diminution with time in the amount recovered. The deterioration of antigen at the site of inoculation was paralleled by a fall in the agglutinin titers of the mice receiving the oil vaccine.
A Specific Antigen Recovered from Tissue Infected with M. Paratuberculosis (Johne's Bacillus)
Authors: Sigurdsson Björn 
Published: January 2023

Discussion and Summary
Intestinal mucosa of sheep infected with M. paratuberculosis (Johne's bacillus) contains two substances that seem to be specific for this disease. One of these substances—the antigen—has been previously described (1, 2, 3, 4). It fixes complement in suitable mixtures with a specific antiserum. The second substance in the infected mucosa—the inhibitor—impedes the fixation of complement by the antigen.
The inhibitor is soluble at all hydrogen-ion concentrations between pH 3 and pH 9. This fact may be used to separate it from the antigen which is insoluble between pH 3 and pH 5. The inhibitor is not precipitated by 3 per cent trichloroacetic acid, and it is insoluble in ether. It will withstand boiling, but does not dialyze through a cellophane membrane.
The inhibiting substance was found to be present in all of the 13 infected intestines which were tested, while 13 normal intestines which were also tested as controls were not found to contain any of the inhibiting principle.
The inhibitor is thus a product of the specific morbid process. It seems reasonable to assume that its function in the tissue is somehow directed against the antigen as it is in vitro, where it inhibits one of the functions of the antigen.
To our knowledge no soluble, specific “antiinfectious” substances have previously been known to arise in the organism as a result of infection except the “antibodies” which are globulins or inseparably associated with globulins. The results reported in this paper, however, do seem to indicate that the organism may also form antiinfectious substances of other kinds, and these may also play a role in the pathogenesis of infectious diseases.
Chemotherapeutic Effect of Acridine Compounds in Experimental Rickettsial Infections in Embryonated Eggs
Authors: Smadel Joseph E. , Snyder John C. , Jackson Elizabeth B. , Fox John P. , Hamilton Howard L. 
Published: January 2023

Summary
2,3-dimethoxy-6-nitro-9(diethyl-amino-hydroxy-propyl-amino) acridine-dibydrochloride, nitroakridin 3582, and an arsenical salt of this compound, rutenol, have a chemotherapeutic effect in embryonated eggs infected with R. prowazeki, R. mooseri, D. rickettsi and R. orientalis. Two other acridines, namely 2-amino-5-nitro-acridine and acriflavine also appear to have some rickettsiostatic effect.
The Preparation of Highly Potent Endotoxin of Hemophilus Pertussis
Authors: Smolens Joseph , Flavell E. H. 
Published: January 2023

Summary
A method is given for the production of unpurified pertussis endotoxin in relatively large amounts. Toxins prepared by repeated freezing and thawing and by sonic treatment are shown to be similar with respect to neutralization by antiserum. The structure of the H. pertussis cell is discussed. Suggestions are made for a theoretically desirable pertussis vaccine.
A Study of Influenza Virus Vaccines by a Serum-Virus Neutralization Test and by Active Immunization
Authors: Eddy Bernice E. 
Published: January 2023

Summary
It required approximately 63 to 125 times more influenza virus vaccine to immunize mice actively against infection caused by intranasal instillation of influenza viruses, PR 8 and Weiss (type A), than it did to stimulate circulating antibodies which neutralized the same quantity of virus, the tests being carried out in identical mice and at the same time. For the Lee strain (type B), five times more vaccine was necessary to produce active immunity comparable to the protection afforded to mice against influenza virus neutralized by immune serum elicited by a small amount of vaccine.
The dilution of vaccine which actively immunized mice against influenza virus stimulated the production of immune serum of higher titer than did the dilutions of vaccine which did not actively protect the mice.
A measurement of the smallest amount of vaccine which would produce immune serum in mice capable of protecting other mice against approximately 103LD50 doses of virus was utilized to determine the potency of influenza virus vaccines.
Demonstration of the “M” Protein in Culture Filtrates of Hemolytic Streptococci of Group A
Authors: Olarte Jorge 
Published: January 2023

Summary
Both type specific T and M proteins have been demonstrated in filtrates from heavy cultures of certain strains of Group A hemolytic streptococci grown in peptone-containing media. M-protein concentrated and partially purified from the culture supernate by ammonium sulfate fractionation is antigenic and produces type-specific precipitating and protective antibodies in rabbits. There is a correlation between the failure of a given strain to release M-protein into the culture medium and its virulence for mice. Strains which are virulent for mice release only traces of M-protein into the culture supernate although M can be extracted from the cells with N/20 HCl. Appreciable amounts of M-protein are present not only in the cells but in the culture filtrates from strains which are not virulent for mice. The possible relationship of these findings to the proteinase recently described by Elliott is discussed.
Complement Fixation with Soluble Antigens of Plasmodium Knowlesi and Plasmodium Lophurae
Authors: Davis Bernard D. 
Published: January 2023

Summary
Soluble antigen from P. lophurae was prepared by extraction with 10 per cent NaCl of the sediment of hemolyzed parasitized duck blood, which resists extraction by isotonic solvents. The complement-fixing activity is associated with unstable opalescent material sedimentable at 16,000 rpm. Treatment of parasitized duck blood with 0.1 per cent formalin prevents disintegration of the parasites and nuclei and extraction of the antigen by 10 per cent NaCl.
Soluble antigen from P. knowlesi was precipitated by 2.25 M (NH4)2SO4 from the supernatant hemolysate of parasitized monkey blood. This antigen is more readily extracted and more stable than the lophurae antigen. Not only is it extracted without disintegration of the parasites, but treatment of the blood with formalin does not inhibit its release by hemolysis.
The lophurae antigen fixed complement with homologous sera, often in high dilution, of immunized or infected ducks, and also with heterologous sera of monkeys immunized or infected with P. knowlesi. The knowlesi antigen, on the other hand, reacted similarly with the homologous monkey antisera, but did not cross-react with the heterologous duck sera.
The reactions of a comparable extract of normal monkey red cells were much weaker; none were obtained with a normal duck red cell extract.
Studies with Antibiotic-Producing Strains of Escherichia Coli
Authors: Halbert Seymour P. , Magnuson Harold J. 
Published: January 2023

Summary
It has been shown that eleven strains of E. coli, which are antagonistic in the living state against a Shigella parcdysenterice Flexner type III, are capable of producing antibiotic when grown on the surface of agar media. Little or no antibiotic developed under various conditions of broth culture. Four strains of E. coli, non-antagonistic in the living state were not capable of producing antibiotic under similar conditions. It has been possible to obtain moderate yields of antibiotic with several strains on a simple synthetic medium. The presence of as much as 25 per cent human serum does not interfere with the action of the antibiotics tested. The properties of the antibiotic of one strain, E. coli 534, have been studied in some detail. They are very similar to those of the substance described by Heatley and Florey (1).
Statistical Analysis of Factors Affecting the Susceptibility of Chick Embryos to Eastern Equine Encephalomyelitis Virus
Authors: Crawley John F. 
Published: January 2023

Summary
By application of Bliss's probit method of analyses it can be shown that: Chick embryos react in a more uniform manner at 39 C than at 35 C to infection with one strain of the virus of Eastern equine encephalomyelitis.With increasing age above eight days the chick embryo becomes more resistant to infection following inoculation via the chorio-allantoic sac route.Conversely, with increasing age up to fifteen days, at least, the embryo becomes more susceptible to infection when inoculated by the yolk sac route.Not only the susceptibility but also the uniformity of response varies with the temperature of incubation, the age of the embryo, and the route of inoculation. The uniformity of response of a population undergoing a change in susceptibility to the virus of equine encephalomyelitis is inversely related to the rate of such change.
Trichomonas Foetus: Experimental Infection in Rabbits
Authors: MacDonald Etta Mae , Nelson Phyllis M. , Byrne H. J. , Tatum A. L. 
Published: January 2023

Abstract
Flagellated protozoa which comprise the genus Trichomonas, having an axostyle and an undulating membrane, occur widely as parasites in man and other animals, and though these infections may vary in degree of severity, depending on the individual host reaction, they are generally difficult to eradicate by the existing chemotherapeutic procedures. Treatment is empirical, and little knowledge of laboratory infections in animals which can be used for evaluating the effectiveness of drugs in these diseases is available. Attempts to infect animals with pure cultures of Trichomonas vaginalis, which causes distressing leukorrhea and vaginitis in humans, have met with little success (1); however, vaginal infections by Trichomonas foetus, which produces sterility and abortion in cattle, can be initiated in rabbits, and an investigation of the infectivity of this parasite for these animals was begun in this laboratory.
In Vitro Action of Various Chemical Agents on Trichomonas Hominis, Trichomonas Vaginalis and Trichomonas Foetus
Authors: MacDonald Etta Mae , Tatum A. L. 
Published: January 2023

Abstract
Trichomonads are actively motile, flagellated, pear-shaped protozoa which occur widely as parasites in man and other animals. Infections may vary in degree of severity depending on the individual host reaction, but they are generally difficult to eradicate. Many types of treatment are recommended, but no reliably efficient chemotherapeutic agents are available; therapeutic procedures are largely empirical and therapy is apt to be uncertain and unsatisfactory.
Attempts to infect animals with bacteria-free cultures of Trichomonas vaginalis (1) have met with little success. In this laboratory, rabbits could not be infected by Trichomonas hominis inoculated intravaginally, and experimental infections of Trichomonas foetus in the vagina of the rabbit are too irregular and unpredictable for practical in vivo tests (2–4). Therefore, in vitro tests on clinical material or on cultures of the organisms remain as a basis for evaluating drugs, particularly for substances which may be expected to act promptly.
III. Relationship to Upper Respiratory Infections of Streptococci Producing a Green Zone on Standard Blood Agar Plates (Smith and Brown's Alpha Type)
Authors: Williams Anna W. , Unneberg Aarlaug , Goldman Agnes , Hussey Helena 
Published: January 2023

Abstract
The primary object of this study, as we have already stated, was to look for evidence of an epidemic strain among cocci of this type.
With regard to this group of bacteria, perhaps more than any other, sweeping statements have been made concerning the relationship of strains to epidemics. This is largely due to their ubiquity and the difficulty of demonstrating clear cut proofs of such relationship and also to the ease with which deductions are made from insufficient evidence.
The most important question relating to this subject about which we have little accurate knowledge, is the question of the permanency of those characteristics which are supposed to be indicative of species, of specific pathogenicity and of related characteristics which might be used in diagnosis.
We know a little of the limits of change in vitro but essential changes in the animal have not yet been demonstrated with controls sufficiently free from error.
The Value of Tissue Extracts of Virus Pigs in the Production of Anti-Hog Cholera Serum
Authors: Haslam Thomas P. 
Published: January 2023

Abstract
I. Introduction. The experiments presented in this article were planned to ascertain whether expressed or extracted juices from the tissues of “virus pigs” could be used as a means of hyperimmunizing hogs in preparing anti-hog cholera serum by the Dorset-Niles method. Uhlenhuth (1) seems to have considered that the saline extract of the blood containing organs was about equal to the blood itself as a means of hyperimmunization. However his methods of hyperimmunization and of testing the potency of the serum vary so greatly from American methods that it is difficult to judge what might be expected under the conditions prevailing here. Our experiment was limited to muscle tissue because the juices recovered from the visceral organs contained many more bacteria than the juices recovered from the musculature.
II. Preparation of Muscle Virus. The pigs killed for virus in the routine production of anti-hog cholera serum were suspended head downward immediately after being killed.
Studies in Dysentery Vaccination
Authors: Cooper Merlin L. , Keller Helen M. 
Published: January 2023

Summary
Mice given by gavage daily doses of 1.2 billion Shigella sonnei as vaccine developed a maximal degree of systemic immunity within 12 days which enabled them to withstand intraäbdominal challenge with more than 59,415 LD50 doses of homologous Shigella.
Sera from mice vaccinated in the same way but not challenged showed a small increase in passive mouse protective power and no increase in agglutinative titers.
Sera from mice which were vaccinated in the same way and which survived intraäbdominal challenge infection showed high mouse protective antibody content and increased agglutinative titers.
Mice given by gavage daily doses of 10 billion Shigella sonnei as vaccine developed a maximal degree of systemic immunity within 9 days which enabled them to withstand intraäbdominal challenge with 61,666 LD50 doses of homologous Shigella.
Studies in Dysentery Vaccination
Authors: Cooper Merlin L. , Tepper Jack , Keller Helen M. 
Published: January 2023

Summary
Six different monovalent vaccines were administered subcutaneously to groups of children 13 to 19 years of age.
One monovalent vaccine was administered subcutaneously, intravenously, and intradermally to three groups of children.
Intravenous administration of vaccine stimulated not only the best homologous antibody response but also the broadest statistically significant heterologous antibody response.
Subcutaneous administration of vaccine stimulated the next best antibody response.
Homologous antibody response was always greater than heterologous antibody response.
Statistically significant homologous antibody response persisted as long as followed in the sera of children given adequate amounts of vaccine. This was six weeks in the case of one vaccine, ten weeks for another, twenty-four weeks for each of four others, and fifty-two weeks for another.
Crossing antibody response was greatest between Shigella flexner I-V, II-W, III-Z, and VII-X.
Heterologous antibody response also occurred between Shigella flexner I-V and Shigella fiexneri VI-Boyd 88.
There was no statistically significant heterologous antibody response between Shigella sonnei and the strains of Shigella flexneri.
There was no heterologous antibody response between Shigella ambigua and the strains of Shigella flexneri.
The antigenic and toxic reactions to these vaccines were related directly to the content of bacterial cells or bacterial nitrogen.
There is evidence of parallelism between toxicity and antibody response.
Shigella vaccine standardized by viable bacterial count to contain ten billion killed bacteria per ml usually stimulated systemic reactions which were too severe.
Shigella vaccine standardized to contain 7.5 mg N/100 ml was not sufficiently antigenic.
We found the passive mouse protective test more sensitive than the agglutinative test for differentiating greater degrees of immune response.
A polyvalent vaccine composed of Shigella fiexneri II-W, III-Z, VI-Boyd 88, Shigella sonnei and Shigella ambigua should stimulate significant antibody response against Shigella flexneri I-V, I I - W , I I I - Z , VI-Boyd 88, VII-X, Shigella sonnei and Shigella ambigua.
The Mouse-Protective Test As a Means of Determining the Inhibitory Effect of Chemicals on Vibrio Cholera
Authors: Little Paul , Subbarow Y. 
Published: January 2023

Summary and Conclusions
Mouse-protective tests were carried out against Vibrio cholera using fifty-seven different chemicals. The chemicals were selected because of activity in in vitro tests against Vibrio cholera as reported by McKenzie and co-workers. The only chemicals showing superior activity were 2-sulfanilamidopyrimidine and its 5-bromo, 5-chloro, and 4-methyl derivatives. Animals having been protected by chemicals were immune when re-inoculated with Vibrio cholera. The xanthene dye, pyronin Y, and the thiazine dye, new methylene blue N, showed slight activity.
Therapy of Experimental Brucella Infection in the Developing Chick Embryo
Authors: Shaffer James M. , Spink Wesley W. 
Published: January 2023

Summary and Conclusions
The superiority of combined streptomycin-sulfadiazine therapy in developing chick embryos infected with Br. abortus, Br. suis, or Br. melitensis is due to a synergistic action of the two therapeutic agents. The relative ineffectiveness of streptomycin alone was apparently not due to the development of resistance by the infecting organism. This synergistic action of streptomycin and sulfadiazine provides supportive evidence for the use of combined therapy in human brucellosis.
Antigenic Studies of a Sucrose-Fermenting Bacterium
Authors: Edwards P. R. , Moran Alice B. , Bruner D. W. 
Published: January 2023

Summary
Two cultures of anaerogenic, sucrose-fermenting, coliform bacteria were found to have Salmonella antigens VI, VIII: d, (i). By growth in appropriate serums they were changed to VI, VIII; i and VI, VIII: j, (i). These changes were reversible. The VI, VIII: i phase was used for the production of specific i serum for Salmonella typing.
A New Type of Phase Variation in the 103 Race of Shigella Paradysenteriae
Authors: Veazie Lyle 
Published: January 2023

Summary
Five antigenically identical strains of Shigella paradysenteriae 103 are described. They differ from most 103 strains in possessing a group antigen indistinguishable from that of the X race. The X antigen was the only antigenic component of one phase of the cultures, and was combined with 103 specific antigen in another phase. The X antigen decreased in quantity over a period of 4 years, being gradually replaced by 103B antigen. Some possible interpretations of this phenomenon and its application to the theories of antigenic structure and classification of the Flexners are discussed.
The Influence of Certain Serum Factors of the Neutralization of Western Equine Encephalomyelitis Virus
Authors: Dozois Theodore F. , Wagner John C. , Chemerda Cecelia M. , Andrew Vivian M. 
Published: January 2023

Summary
A method is outlined for the separation of rabbit complement into two fractions lacking C′1 and C′2. These fractions are hemolytically inactive by themselves, but fully active when combined in single unit amounts.
It is shown that C′3 and C′4 of rabbit complement are inactivated by the same means employed for the inactivation of these components in guinea pig and human complements.
Hemolytic titrations are given for the four components of rabbit complement. These components have less hemolytic activity than the corresponding components of guinea pig and human complements, but are otherwise similar.
The ability of fresh normal serum to enhance the virucidal capacity of heated immune serum is verified and the thermolabile nature of this property of fresh normal serum is confirmed.
Blood complement is shown to be the agent in fresh rabbit serum responsible for increasing the neutralizing action of heated immune serum against the virus of Western equine encephalomyelitis.
The second, third and fourth components are shown to be involved in the role of complement in virucidal tests. It is further demonstrated that either the first component is not necessary or, if required, that only a minute amount of this component is needed in this reaction involving complement.
Use of Ultraviolet Absorption Spectroscopy in the Quantitative Precipitin Reaction
Authors: Gitlin David 
Published: January 2023

Summary
The effects of acid and alkali on several purified plasma proteins employed as antigens, and on their homologous specific precipitates, have been reported. The ultraviolet absorption properties of these antigens and their homologous rabbit antibodies have been shown to be largely dependent upon their tyrosine and tryptophane content. The ultraviolet absorption properties of the rabbit antibodies studied are very similar to those of human serum γ-globulin, and it is suggested that the tyrosine and tryptophane content of the rabbit antibodies is very similar to that of human serum γ-globulin. E 1% 1cm has been calculated for several rabbit antibodies. A method is described for using the spectrophotometer for studies of the quantitative precipitin reaction. The spectrophotometric method of determining total and antibody protein in specific precipitates has been applied to the study of the precipitation of several human and bovine plasma proteins by their homologous rabbit antisera.