bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Significance of Age of Rabbits for the Elicitation of the Shwartzman Phenomenon
Authors: Witebsky Ernst , Neter Erwin 
Published: January 2023

Abstract
A small percentage of adult rabbits is refractory towards the elicitation of the Shwartzman phenomenon. There is a definite relationship between the type and amount of toxin employed and the percentage of positive reactions. Shwartzman (1) reported that about 30 per cent of rabbits are refractory if typhoid agar-washing filtrate is used and only a few per cent with meningococcus agar-washing filtrate. It seemed of interest to determine whether constitutional factors, such as age, may play a rôle in the Shwartzman phenomenon. One litter of a few days old rabbits did not display the Shwartzman phenomenon in an experiment carried out by Gratia and Linz (2). Freund and Hosmer (3) observed that the appearance of the hemorrhagic local skin reaction depends upon the age and weight of the rabbits tested. A positive reaction was obtained in young rabbits weighing between 1100 and 2000 grams only after the reinjection of the bacterial agar-washing filtrate, but not after the reinjection of starch.
The Reaction of the Nursling Rabbit to Vaccination with Vaccine Virus
Authors: Pearce Louise , Hu C. K. , Rosahn Paul D. 
Published: January 2023

Summary and Conclusions
The results of the vaccination with vaccine virus of 1185 nurslings in a rabbit breeding colony are reported. Failure to develop a local reaction to vaccination was of frequent occurrence, especially in very young rabbits. A characteristic finding in many animals was the occurrence of generalized manifestations, the most striking of which was a cutaneous papular eruption.
Vaccination was carried out in three successive experiments on December 19, 1933, January 24, and March 21, 1934. The general character of the resulting vaccinia underwent a progressive decline in severity, and in the last experiment there was little clinical evidence of infection.
The results are discussed from the standpoint of the reaction of the host and particularly with reference to such factors as the nature of the local response to vaccination, the age of the animal, the condition of fostering, and the immune or susceptible state of the nursing female.
The Complement Fixation Reaction in Experimental Equine Encephalomyelitis, Lymphocytic Choriomeningitis and the St. Louis Type of Encephalitis
Authors: Howitt Beatrice F. 
Published: January 2023

Summary
The complement fixation test may be applied to the differentiation of the viruses of equine encephalomyelitis, lymphocytic choriomeningitis and St. Louis type of human encephalitis, respectively. The eastern, western and Moscow 2 strains of equine encephalomyelitis were clearly differentiated when using guinea pig brain antigens, but there was occasional cross fixation between the American strains when using mouse brain antigen. The Russian strain was quite distinct from either. There was no cross fixation between serums and antigens of the equine encephalomyelitic group and those of normal guinea pig and normal mouse or with the viruses of Borna disease, of lymphocytic choriomeningitis and of the St. Louis human encephalitis, respectively. Similarly there were no cross reactions between the antigens and serums of the 2 latter viruses nor between these and normal guinea pig brain antigens and serums, respectively. Complement fixing antibodies when once developed in hyperimmunized animals for the equine viruses may be retained for at least 3 months. The titer may decline but can be restored by virus injections. They may also be present in serums kept for at least 1 year and 10 months in the icebox. Neutralizing substances for the equine strains usually appeared somewhat earlier than the complement fixing antibodies. Antigens of the eastern, western and Moscow 2 strains of virus, respectively, gave positive fixation when passed through ultrafilters of 470 mu porosity. Potency was reduced by filtration through 200 mu membranes and entirely lost by those of 160 mu. Heating to 55°C. destroyed the antigenicity of the unfiltered western antigens and partially affected those of the eastern and Russian strains of equine encephalomyelitis. Heated filtrates were negative. The unfiltered mouse brain antigens of the American strains and those filtered through 470 mu gradocol membranes remained viable to mice, but not if heated or passed through finer filters. The Moscow 2 antigen remained viable only if untreated by heat or filtration.
The Effect of Temperature Upon Combination and Aggregation and Upon Equilibrium in the Reaction Between Antigen and Antibody
Authors: Follensby Edna M. , Hooker Sanford B. , Leach Elizabeth T. 
Published: January 2023

Abstract
According to a current theory, reaction between antigen and antibody occurs in two stages. It is thought that specific combination takes place during the first stage and is followed by the secondary reaction of aggregation, considered specific by some investigators and non-specific by others. The second stage has been more thoroughly studied than the first. There are, in fact, few systems in which combination can be easily studied apart from aggregation; consequently we know little about the relationship between the two stages, whether the reactions proceed at the same rate and are similarly affected by such factors as temperature and concentration. The reaction between diphtheric toxin and antitoxin is one in which both combination and aggregation can be investigated. Glenny (14) has said of this system “… the appearance of visible flocculation may not be a simple function of the rate of preliminary combination of toxin with antitoxin, presumed to be loose, and this may bear no simple relation to the rate of ultimate combination, which is assumed to be of a firmer nature.”
Demonstration by the Electron Microscope of the Combination of Antibodies with Flagellar and Somatic Antigens
Authors: Mudd Stuart , Anderson Thomas F. 
Published: January 2023

Abstract
The electron microscope, by extending resolving power to a present practical limit of about 50 Ångstrom units (1, 2), is affording the opportunity for investigation of structures hitherto inaccessible to direct examination.
The electron microscope is also opening up new possibilities of investigation of process and mechanism, as well as of structure. Recording by electron microscopy of the process of lysis by phage (3), of the interaction of virus molecules with colloidal gold particles (4), of intracellular reduction of tellurite ion (5), and of the combination of virus with antivirus molecules (6, 7), may be cited as cases in point.
The present study concerns the sensitization of flagellate typhoid and paratyphoid bacilli and of Bacillus subtilis with rabbit antisera. Alterations of the bacterial cell-wall and flagella by deposition of specific antibodies which combine with surface somatic and flagellar antigens have long been deduced from the behavior of sensitized bacteria in agglutination (8) and phagocytosis and from parallel alterations in cohesiveness, wetting properties and electrophoretic properties (9, 10).
Experimental Diphtheric Paralysis
Authors: Feiner Rose R. 
Published: January 2023

Summary
Diphtheric paralysis in guinea pigs was produced by the intravenous injection of 0.1 to 0.4 mld of toxin alone. The ratio of the paralytic dose to the minimal lethal dose was the same with each of four toxins used, including a highly purified, a gravis, a mitis, and an intermediate toxin. In vitro contact of toxin with nerve tissues caused neither a loss in lethal nor in paralytic action of the toxin. The loss of ability of heat-, light-, formalin-, or H2O2-treated purified toxin to produce paralysis paralleled the loss of ability to produce cutaneous necrosis or death. The non-toxic supernates of neutral toxin-antitoxin mixtures did not produce paralysis. Tissues removed from paralyzed guinea pigs were not capable of inducing paralysis in normal guinea pigs. No local peripheral nerve immunity developed as a result of one attack of paralysis. Guinea pigs once recovered succumbed to the re-injection of paralyzing doses with no difference in length of incubationary period, duration, or severity, as compared with the first attack. The intraneural injection of toxin produced a mild paresis that appeared relatively soon after injection, but it did not resemble true diphtheric paralysis. There was no evidence of centripetal diffusion of toxin.
Studies on the Mechanism of Sulfonamide Bacteriostasis, Inhibition and Resistance
Authors: Strauss Elias , Dingle John H. , Finland Maxwell 
Published: January 2023

Summary
A strain of E. coli was studied which, in a simple synthetic medium, required nicotinic acid or nicotinamide for growth from small inocula. Growth was also improved by increasing the concentration of carbon dioxide in the atmosphere.
Sulfathiazole, sulfadiazine, sulfapyridine, sulfaguanidine and sulfanilamide were bacteriostatic in relatively small concentrations, as compared with their activity against this organism in complex media.
Nicotinamide, nicotinic acid and coenzyme I did not inhibit the action of these sulfonamide drugs.
P-aminobenzoic acid is a strong inhibitor of sulfonamide action, methionine a weak inhibitor. Differences in the effect of methionine on various sulfonamide drugs may be quantitative rather than qualitative.
The development of resistance to sulfonamide action has been produced with E. coli in a simple medium. P-aminobenzoic acid prevents the development of sulfonamide resistance, while methionine delays but does not prevent the development of resistance.
The Influence of Iron on the Production of Diphtheria Toxin
Authors: Mueller J. Howard 
Published: January 2023

Summary
The observation of Pappenheimer and Johnson that abundant formation of diphtherial toxin occurs only in a relatively narrow zone of concentration of iron has been thoroughly verified. It has not proved possible to shift or extend this zone by the addition of other inorganic or organic materials (except manganese salts which seem partially to take the place of iron). On the other hand, addition of relatively large quantities of iron does not completely prevent toxin-formation, but rather reduces it to a comparatively low level. It is suggested that such a level represents normal production, whereas the larger amount obtained under conditions of iron starvation is the result of a compensatory mechanism in which the iron-free toxin molecule takes part in some process which is ordinarily catalyzed by an iron-containing enzyme.
Toxin-Production As Related to the Clinical Severity of Diphtheria
Authors: Mueller J. Howard 
Published: January 2023

Summary
C. diphtheriae elaborates relatively little toxin in the presence of concentrations of iron present in the throat. In the average case of mild diphtheria comparatively small amounts are probably formed. Severe (gravis) diphtheria may result from infection with strains able to produce more toxin in the presence of abundant iron. Three non-gravis types have been shown to produce approximately 3 MLD/ml under these conditions, whereas a gravis type produced 40 MLD. It is probable that a difference of this order is sufficient to explain observed variations in the clinical severity of the disease.
The Inhibition of the Bactericidal Power of Human and Animal Sera by Antigenic Substances Obtained from Organisms of the Typhoid-Salmonella Group
Authors: Cundiff Richard J. , Morgan Herbert R. 
Published: January 2023

Summary
Sera with high titers of bactericidal antibody can be obtained in man and the rabbit by repeated intravenous injections of a purified somatic antigen of E. typhosa. The bactericidal activity of antityphoid immune sera prepared by injection of bacterial cells or the purified somatic antigen of E. typhosa is inhibited by the addition of the somatic antigen. The somatic antigens of S. enteritidis and S. paratyphi B show a similar but less marked effect which is in accord with the antigenic classification of White and Kauffmann. The specificity of this inhibition is further indicated by the failure of an extract of Friedländer's bacillus, type A to exert any effect on the bactericidal activity of the immune sera.
Potency-Determination of Antipertussis Serum by the Mouse-Protective Test
Authors: Holm August , Bunney William Edward 
Published: January 2023

Summary
Reproducible results may be obtained by the procedure given for conducting the mouse-protective test with antipertussis serum.
This has made it possible to establish a provisional standard unit for use in the evaluation of antipertussis rabbit-serum by the mouse-protective test.
A provisional standard unit is defined as that amount of standard serum which will protect 50 per cent of the mice against 2 MLD of a virulent strain of H. pertussis suspended in 4 per cent gastric mucin.
Antipertussis rabbit-sera may be standardized in terms of a control serum using White's formula.
This method of conducting the mouse-protective test in the potency-determination of antipertussis sera is practical and assays specific protection in terms of provisional units.
Effect of Induced Hypercholesterolemia on Antibody-Nitrogen Production (Pneumococcus Type 2) in Rabbits
Authors: Member Samuel , Bruger Maurice , Ehrlich Sylvia B. 
Published: January 2023

Abstract
It is sometimes assumed that serum- or tissue-cholesterol is related in some fashion to the process of immunity. Borchardt (1) found that in cats the intravenous administration of colloidal cholesterol increased the resistance of the animals to Staphylococcus aureus infection. Recently, Chassin and Bruger (2) demonstrated that after the injections of typhoid vaccine, hypercholesterolemic rabbits showed a higher agglutinin titer against E. typhosa than control rabbits with normal blood-cholesterol. Member, Bruger and Chassin (3) found that the total and ester-cholesterol content of the blood was maintained at normal levels during the early stages of immunization of horses with pneumococci. In the later stages of immunization, however, a significant decrease in these sterols occurred.
In the present investigation rabbits were used. The experiments were devised to determine the effect of cholesterol-feeding upon antibody-nitrogen production in rabbits receiving large amounts of pneumococci.
A Large-Scale Serum-Neutralization Survey of Certain Vertebrates as Part of an Epidemiological Study of Encephalitis of the Western Equine and St. Louis Types
Authors: Hammon W. McD. , Lundy H. W. , Gray J. A. , Evans F. C. , Bang F. , Izumi E. M. 
Published: January 2023

Summary
From an irrigated western valley region, where both St. Louis and western equine encephalitis occur in annual epidemics, 576 sera representing 74 species were examined by means of the neutralization-test for antibody against both viruses. Each of the viruses was neutralized by approximately 50 per cent of the sera from domestic fowl and to a less extent by sera from domestic mammals. The sera from wild species from each group showed a significantly lower percentage of positives than those from the respective domestic groups. Only 8 per cent of the sera from wild mammals possessed antibodies. No sampling error was found which would alter the significance of these differences. From “control” areas, where encephalitis was not recognized, 132 sera, largely from domestic species, were tested. Only one was positive. This confirms the specificity of the neutralization-test. In this valley the epidemiology of these two diseases appears to be parallel. It is concluded that many of these birds and mammals, principally the domestic fowl, probably serve as reservoirs for infection of mosquitoes. The percentage of susceptible horses which become infected is very high.
Antepartum Transmission of Lymphogranuloma Venereum Antibodies and Their Duration in the Infant
Authors: Levine Sonnia , Bullowa Jesse G. M. , Scheinblum Irving E. 
Published: January 2023

Summary
Fifteen, or four and two-tenths percent, of two hundred and eighty antepartum women without signs or symptoms of lymphogranuloma venereum gave positive Frei reactions as well as complement fixation for lymphogranuloma venereum. The infants of ten positive Frei reactors were studied for complement fixation in their first week of life and again after 8 to 14 weeks. Correspondence between the titer of the complement fixation of the sera of mother and infant was found during the first week of life. After 8 to 14 weeks the infant's sera became negative. Only the antibodies for lymphogranuloma venereum were temporarily present in the infants of mothers with asymptomatic lymphogranuloma venereum.
Studies on the Immobilization-Reaction of Trichomonas Foetus (Protozoa) in Cattle
Authors: Morgan Banner Bill 
Published: January 2023

Summary and Conclusions
Immune bodies were produced by the injection of cows with living or formalinkilled Trichomonas foetus. The degree of antibody-response was low, as determined by the test described above, and results indicate that T. foetus is not highly antigenic. In the sera of five heifers injected intramuscularly with washed motile trichomonads, 2 heifers with formalin-killed trichomonads, and 2 heifers intravenously with living trichomonads, immobilization of the microorganisms was observed in dilutions ranging from 1:4 to 1:128. Thus, there there was some degree of variation of titer among the cows. Inoculation with a single injection of trichomonads after a rest period of approximately 102 days produced titers as high as the previous maximal titer or higher. The average time for the agglutinins to appear after the first injection was 17 days, for maximal immobilization 55 days, for total duration of the agglutinins 177 days and duration of complete immobilization 40 days. No agglutinins were detected in the sera of 400 normal trichomonad-free cows and 52 normal trichomonad-free bulls. Also, this test failed to show agglutinins in 11 trichomonad-infected bulls. Sera from 51 cows divided into 3 groups according to the type of trichomonad-infection were tested. In 10 cows in which trichomonads were recovered from the vaginal tract all sera were negative. In 12 cows with early abortion produced by T. foetus, only 2 sera reacted, one with a complete immobilization at a dilution of 1:1, and one with a partial immobilization at the same dilution. In the 29 cows with trichomonad-pyometra only 2 sera reacted slightly, both with partial immobilization at a 1:1 dilution. On the data presented with 9 injected animals, 400 normal cows, 52 normal bulls, 11 infected bulls, and 51 infected cows, it appears that the immobilizationreaction cannot be successfully utilized as a means for the diagnosis of bovine trichomoniasis.
Group-Specific Substances in the Saliva of the New-Born
Authors: Wiener Alexander S. , Belkin Ruth B. 
Published: January 2023

Summary
A series of thirty pairs of saliva-samples from mothers and their new-born infants were tested for their content of group-specific substances. It was found that the distinction between secretors and non-secretors was as sharp in the infants as in the mothers, indicating that this character is fully developed at birth and contradicting the report of Hartmann.
Prophylactic Immunization Against Carrión's Disease
Authors: Howe Calderon , Hertig Marshall 
Published: January 2023

Summary and Conclusions
The incidence of infection with Bartonella bacilliformis, and of clinical Carrión's disease in non-immune military personnel stationed at three points in the verruga zone is estimated on the basis of observations made by one of the authors (M. H.) during an 18-month period preceding the present experiment. Preparation of formolized suspensions of B. bacilliformis, is described, these suspensions constituting the vaccine used herein. A group of 22 guards without previous history of Carrión's disease, thus presumably non-immune, were inoculated subcutaneously with 1 ml of formolized vaccine prior to being stationed in the verruga zone. Most of these guards received one or two more injections of vaccine during the first two weeks of their service. The majority were followed by the authors for the ensuing seven months, blood for cultures and serum being taken from each guard on several occasions during this period of observation. This subcutaneous inoculation of 22 humans with formolized suspensions of B. bacilliformis resulted in the appearance in their serum of a high titer of homologous agglutinins. From the blood of twelve, or 55 percent, of these, B. bacilliformis was cultured on one or more occasions during the period of observation following vaccination. Five out of the twelve developed a mild degree of verruga eruption. All twelve had shorter or longer periods of mild systemic symptoms. Only one required hospitalization, being the sole member of the whole group who was at all incapacitated. Comparison of these results with the observations made on unvaccinated guards during the 18 months preceding the present experiment warrants the belief that active immunization as here carried out, although not preventing infection, may definitely ameliorate the course of potentially serious Carrión's disease. The protective effect of the vaccine used is thought not to be directly related to the specific serum agglutinins which result from its administration. The exact mechanism of protection is not clear.
The Relation of the Dose of Antigen to the Degree of Anaphylactic Shock in Dogs
Authors: Dragstedt Carl A. 
Published: January 2023

Abstract
The term anaphylaxis means absence of protection and thus expresses recognition of the fact that the sensitivity of the animal is more important than the toxicity of the antigen in determining the occurrence of a reaction. This view is appreciated by every one when contrasting the behavior of sensitized animals with that of normal animals. It is not, however, so generally appreciated in comparing one sensitized animal with another. For example, there are many published reports in which investigators have studied the prophylactic effect of various agents by sensitizing a series of animals, ascertaining a “fatal dose” of antigen in a small group of control animals, and determining whether or not some of the treated animals could withstand a larger dose of antigen. The rationale of such experiments imputes a toxicity to the antigen, which should be expressed by a positive correlation between the severity of the anaphylactic reaction and the dose of the injected antigen, such as is the case for the lethal action of directly poisonous agents.
Attempts to Obtain Specific Agglutination of Mixtures of Collodion Particles or Bacterial Cells with Virus and Antiviral Serum
Authors: Pearson Harold E. 
Published: January 2023

Summary
When collodion particles or bacterial cells were mixed with influenzal virus and then exposed to immune serum from man or ferret, specific flocculation was not observed although a variety of technics was employed. Nor was specific flocculation noted when the Lansing strain of poliomyelitic virus and serum from immune monkeys were studied under similar conditions.
Specific flocculation was not obtained when the bacterial-cell-agglutination (B.A.) method was employed in tests using the above-mentioned materials or in tests using sera from immune rabbits and the viruses of St. Louis encephalitis or eastern equine encephalitis.