bluuebunny/crossref_metadata_2025_split huggingface dataset:
THE OCCURRENCE OF DEGRADED PNEUMOCOCCI IN VIVO
Authors: Reimann Hobart A. 
Published: June 2004

It is conceivable that a change from the virulent, non-phagocytable S form of Pneumococcus to the avirulent phagocytable R form may take place in pneumococcus disease, but the experiments here reported do not settle the question whether or not this is an important factor in determining the outcome in natural infection. It has been shown experimentally that the degradation from the S form to the R form actually does take place in cultures of Pneumococcus growing in agar subcutaneously embedded in guinea pigs, in agar enclosed in vials subcutaneously embedded in rabbits, and spontaneously in the blood stream of infected horses. However, it was not possible in any of the experiments here cited to demonstrate the complete change from S to R pneumococci before the bacteria disappeared from the body. When the intermediate or R forms did appear, they were always accompanied and usually exceeded in number by the S forms and all three forms disappeared together. S organisms may disappear entirely without evidence of first going through the intermediate and R stages. On the other hand, contrary to expectations, pure cultures of R forms remained viable in subcutaneous foci for weeks although apparently freely accessible to the action of phagocytes. It seems of some significance that the R forms appeared early in the vials (inoculated with S pneumococci) in immunized and normal rabbits alike, indicating that the presence of demonstrable specific immune bodies was not alone responsible for the variation of the bacteria.
Of some importance also is the fact that R forms were never derived from similarly prepared control cultures growing in vitro at the same temperature and immersed in normal serum, although the S forms remained viable and unaltered for 6 weeks. It is likely that variations of pneumococci do not occur readily when S cultures are exposed to normal serum in vitro, especially when growing in closed vials under a diminished oxygen supply, for it has previously been shown (2) that only slight variation occurs even after prolonged (240) transfers in heterologous serum broth in the test-tube. It is possible, therefore, that the variation which occurred among pneumococci growing in agar vials embedded in normal rabbits was actually provoked by unknown influences in the living tissue fluids.
Although R forms have been shown to occur in vivo, no positive evidence can be derived from these experiments to prove that recovery from pneumococcus infection depends upon the degradation of the virulent S forms of pneumococci to the avirulent R forms and the subsequent destruction of the latter by phagocytes.
STUDIES ON THE PHYSICAL AND CHEMICAL PROPERTIES OF THE VIRUS OF FOOT-AND-MOUTH DISEASE
Authors: Olitsky Peter K. , Boëz Louis 
Published: June 2004

The virus of foot-and-mouth disease exhibits a remarkable resistance to such bactericidal agents as the narcotic solvents (alcohol, ether, chloroform), or such antiseptics as phenol, bichloride of mercury, or cresol, as shown by tests made by others and ourselves. We have shown, however, that the resistance of the incitant to these chemicals is really masked. It is due to the fact that the reagents coagulate the proteins of the medium in which the virus is, as a rule, suspended. As a result the active agent is protected by the coagula which prevents direct contact with the chemicals. On the other hand, if advantage is taken of the periodic phenomenon attending such processes, and coagulation is prevented, the virus can then be brought under direct action of the antiseptics. Under these conditions, the incitant is more sensitive to destruction by the chemicals than is the living staphylococcus. As a corollary, the virus is destroyed as rapidly, or even more so, than are staphylococci by substances such as sodium hydrate (1 to 2 per cent solutions), or antiformin (1 per cent solution) which do not form coagula. We are therefore compelled to contradict the opinion that the extraordinary resistance to certain chemicals of the virus of foot-and-mouth disease, as it ordinarily occurs admixed with proteins, is an indication of its inanimate character.
The results of a large series of experiments lead to the conclusion that of a number of antiseptics employed the sodium hydrate in 1 to 2 per cent solutions is an effective virucide. It is capable of killing the virus within 1 minute as shown by tests on cattle and guinea pigs. Furthermore, its effectiveness is not diminished even when the virulent material is admixed with cattle's urine, with manure, or with garden soil. The experimental evidence and the cheapness suggest its use in field practice as a disinfectant.
STUDIES ON THE PHYSICAL AND CHEMICAL PROPERTIES OF THE VIRUS OF FOOT-AND-MOUTH DISEASE
Authors: Olitsky Peter K. , Boëz Louis 
Published: June 2004

No multiplication of the virus in vitro was observed. We have found, however, that the optimum conditions necessary for the preservation of the virus in artificial media are as follows:
The hydrogen ion concentration of the medium should be 7.5 to 7.6, not only at the beginning, but, and more important, at the conclusion of the period of observation. A strict anaerobic atmosphere is also favorable, as is a temperature below 37°C. A semisolid structure of the medium appears to be advantageous and this can be effected by the use of ¼th per cent agar or 10 per cent gelatin. Of the two, the gelatin is more desirable, and of the latter the most effective material is gelatin from which the impurities have been most thoroughly removed, namely the gelatin employed by Loeb for his isoelectric determinations. This material is best adjusted to the proper hydrogen ion concentration (7.5–7.6) with potassium hydroxide and not with buffer phosphate.
Gelatin is the simplest of protein media available and its employment is in keeping with the principle we have found that the requirements for life of the virus of foot-and-mouth disease are of the simplest. The addition of organic or complex protein substances, such as dextrose, broth, serum, lipoids, etc., to a simple basic medium interferes with the effectiveness of the latter. It is thus not surprising that we were unable to confirm the cultural results of Frosch and Dahmen for neither their medium nor its components or their method satisfies the essential conditions necessary to maintain artificially the life of the virus.
Furthermore, from the standpoint of technique it was found necessary when comparing 2 or more media for their value in preserving the incitant, to employ all of them in a parallel experiment with the same sample of virus, for the factors of potency of the active agent, contamination, and changes in hydrogen ion concentration, if variable, may give rise to faulty interpretations. Moreover, activity in 3 successive subplants may be regarded as mere preservation but not multiplication of the virus.
Finally, we discuss the status of the virus from the point of view of its fluid or particulate, and its animate or inanimate, characters.
OXYGEN POISONING IN MAMMALS
Authors: Binger Carl A. L. , Faulkner James M. , Moore Richmond L. 
Published: June 2004

1. Oxygen in concentrations of over 70 per cent of an atmosphere is poisonous to dogs, rabbits, guinea pigs and mice.
2. The poisonous effects manifest themselves in drowsiness, anorexia, loss of weight, increasing dyspnea, cyanosis and death from oxygen want.
3. The cause of oxygen want is a destructive lesion of the lungs.
4. The lesion may be characterized grossly as an hemorrhagic edema. Microscopically there is to be seen in varying degrees of intensity (a) capillary engorgement with hemorrhage, (b) the presence of interstitial and intraalveolar serum, (c) hypertrophy and desquamation of alveolar cells, (d) interstitial and alveolar infiltration of mononuclear cells.
5. The type of tissue reaction is not characteristic of an infectious process and no organisms have been recovered at autopsy from the heart's blood or from lung puncture.
6. The poisonous effects of inhalations of oxygen-rich mixtures do not appear to be related to impurities in the oxygen, nor are they related to faulty ventilation, excessive moisture or increased carbon dioxide in the atmosphere of the chambers in which the experimental animals were confined.
STUDIES ON THE BACTERIOPHAGE OF D'HERELLE
Authors: Bronfenbrenner J. , Muckenfuss R. 
Published: June 2004

We have been able to confirm the observations of Twort as well as of Gratia, that dead staphylococcus may undergo lysis if, in addition to a suitable bacteriophage, there is also present live staphylococcus. Moreover, we have endeavored to ascertain the mechanism of this phenomenon and have found that in order to elicit it it is necessary to control the numbers of live and dead bacteria in the mixture. An excess of dead bacteria interferes with lysis by adsorbing the bacteriophage before it has the opportunity to initiate necessary changes in the live bacteria, so that all lysis is prevented. The phenomenon is specific, that is, the lysis of live bacteria is accompanied by lysis of dead bacteria of the same species only. Lysis of dead bacteria occurs best with staphylococcus, an organism which easily undergoes spontaneous autolysis under appropriate conditions. In the case of B. coli or B. dysenteriæ the lysis of the dead bacteria is uncertain. Dead bacteria need not be present in the mixture at the beginning of the experiment; they will be dissolved if added any time before, during, or after the completion of lysis of live bacteria.
If the test is performed so that a suitable semipermeable membrane is interposed between the dead and live bacteria, the dead bacteria are not dissolved, in spite of the lysis of live bacteria on the other side of the membrane. The agent determining the lysis of dead bacteria is not diffusible, while the principle initiating the lysis of live bacteria diffuses freely and is demonstrably present on both sides of the membrane. The complete independence of the agent causing dissolution of dead bacteria from bacteriophage can also be shown by separating the two agents by means of filtration, or by adsorption on bacteria.
The ferment-like substance responsible for the lysis of dead bacteria is different from the bacteriophage. It is not diffusible through collodion, it is easily adsorbed on clay filters, it is heat-labile, and is inactivated on standing.
An agent possessing identical properties was found in cultures of staphylococcus undergoing spontaneous autolysis in the absence of bacteriophage, but in this instance the agent appeared in the filtrates considerably later than it did when phage was present.
BACTERIUM LEPISEPTICUM INFECTION
Authors: Webster Leslie T. , Burn Caspar 
Published: June 2004

In this paper we have attempted to describe the manner of spread of an endemic, native, respiratory infection and a method for its control. The essential factor determining the prevalence of such an endemic disease is, we believe, host susceptibility, which is controlled by hereditary and environmental influences. Furthermore, it seems probable that the amount of this population susceptibility determines the dosage of specific microbes available to the population.
An increase in dosage in the herd is followed by an increase in the spread and severity of the infection, and a decrease by a corresponding alleviation. Hence, two methods for the prevention of epidemics are available: (1) an enhancement of population resistance, and (2) the reduction to a minimum of available dosage. These procedures have proved successful for 3 years in maintaining a population of breeding rabbits, in the midst of a badly infected community, entirely free from Bact. lepisepticum infection.
Confirmation of the above conclusions has been gained from other studies in the field of experimental epidemiology. Dr. D. T. Smith (2), at Saranac, New York, found that changes in population susceptibility were responsible for a severe outbreak of Bact. lepisepticum infection and septicemia. Freund (3), at Berlin, has just published an interesting account of respiratory epidemics of rabbits and guinea pigs, apparently brought about by sudden changes in temperature and housing conditions. Pneumonia and Pasteurella infection, endemic in the population, increased suddenly in extent and severity. Nevertheless, neither endemic nor epidemic strains of the microorganisms were found to be especially virulent. Dr. Theobald Smith (4), in a study of paratyphoid epidemics of guinea pigs, has made similar observations. He noted that pregnant females acted as the foci of infection, and that from these individuals, presumably of lessened resistance, the bacteria were given off and infection was spread.
The studies in experimental epidemiology are rapidly reaching a stage where they may be applied to the problems of human disease. Indeed, more recent observations of the mode of spread of pneumonia (5–7), scarlet fever (8), typhoid (9, 10), plague (11), diphtheria (12–14), measles (15), and tuberculosis (16–18) increasingly show a tendency to discard the theory of fluctuating microbic virulence and to emphasize the importance of the host factors.
THE ACTION OF THE SYMPATHETIC UPON THE EXCITATORY PROCESS IN THE MAMMALIAN HEART
Authors: Andrus E. Cowles , Martin Louis E. 
Published: June 2004

Stimulation of the sympathetic nerve endings, after paralysis of the vagus, accelerates the transmission of the excitatory process in the dog's auricle.
Following the functional exclusion of the vagus ergotamine slows the rate of the sinus rhythm, depresses A-V conduction, and delays the transmission of the excitatory process in the auricle.
The relation of the sympathetic and parasympathetic nerves in the control of the cardiac rhythm is discussed.
ON THE INFLUENCE OF ACID GROUPS ON THE SEROLOGICAL SPECIFICITY OF AZOPROTEINS
Authors: Landsteiner K. , van der Scheer J. 
Published: June 2004

The method of partial synthesis of antigens as employed in the foregoing experiments obviously cannot be substituted for the chemical study of natural antigens. But some questions of a rather general nature not easily accessible to investigations of the latter sort, may be approached by the use of artificial protein compounds. Thus the results reported indicate a peculiarity of certain chemical structures such as acid radicals.
The group of immune sera obtained by injecting azoproteins made from non-acid azo components had a wide range of activity. Substituents like CH3, OCH3, NO2, Cl, Br, I, in the aromatic nucleus altered the reactions to a moderate degree only, in most cases. The effects were dependent more on the position than on the nature of the substituents. Two substances were found, however, which had a pronounced effect on the specificity of the compound protein, namely acetyl-para-phenylenediamine and para-aminoacetophenone. In consideration of the above facts it is uncertain whether the antigenic changes noticed by Obermayer and Pick (7) after treating proteins with nitric acid, nitrous acid or iodine are mainly due to the substitution of hydrogen in the benzene ring by NO2 and I, as is the general belief, or to other changes of the protein. This question had been raised already by the observation that the proteins treated with HNO3 or HNO2 containing respectively the nitro or the diazo group, did not differ substantially in their serological properties (8).
The antigens made from acid compounds form a group with distinctive features. In the first place the presence of acid radicals destroys the reactivity with the immune sera for the non-acid substances. This influence is so marked that even the reaction with the species specific part of the protein, if such is present, appears to be diminished. Also the sera produced with the acid antigens react but feebly with the non-acid azoproteins. Accordingly it was possible to show that by hydrolysis of the ester of an aromatic acid contained in an azoprotein the serological reactions of the antigen underwent a radical change.
The presence of a free carboxyl group in the antigens not only determines the characteristics mentioned but there is reason to believe that it increases markedly the degree of specificity exhibited by the antigens and the corresponding immune sera, when cross-tests are made with a number of acid azoproteins and their antisera. This is brought out by a comparison of the results of the present investigation with those described previously (3). It is of interest in this respect that the specific carbohydrates found by Avery and Heidelberger in pneumococci and pneumobacilli are mostly, if not in all cases, compounds of distinctly acid character.
THE DEVELOPMENT OF AGGLUTININS AND PROTECTIVE ANTIBODIES IN RABBITS FOLLOWING INHALATION OF PNEUMOCOCCI
Authors: Stillman Ernest G. 
Published: June 2004

1. Following repeated inhalations of Type I pneumococci agglutinins and protective antibodies can be demonstrated in the serum of rabbits.
2. The percentage of rabbits whose serum shows agglutinins remains stationary after the 5th exposure, but the percentage of rabbits showing protective antibodies in their sera steadily rises.
PHYSICAL, CHEMICAL, AND BIOLOGICAL STUDIES ON THE VIRUS OF VESICULAR STOMATITIS OF HORSES
Authors: Olitsky Peter K. 
Published: June 2004

A taxonomic study of the virus of vesicular stomatitis is presented along with evidence additional to that already reported1 to show the similarity of this virus to that of foot-and-mouth disease. The connection of the two is discussed and the deduction drawn that their generic relationship is close. On the contrary, the differences between these two viruses and the herpetic are sufficiently marked to indicate a lack of generic connection among the three.
The results of a comparative study on the effects of particular wave-lengths and energies of monochromatic ultra-violet light on the virus and on Staphylococcus aureus reveal that the adsorption of specific energies by the two is parallel. Since the adsorption of specific energies is an index of chemical character, these experiments suggest that the virus is similar in character and chemical constitution to bacterial protoplasm.
SURFACE TENSION OF SERUM
Authors: du Noüy P. Lecomte 
Published: June 2004

Experiments are reported which indicate that a shift toward higher concentrations is observed in the minimum value of the static surface tension when plasma instead of serum solutions is used. The amount of the shift, expressed as a function of the concentration, shows that the figures are in satisfactory agreement with the determined amount of fibrinogen in the plasma.
Some evidence is given that "plasma molecules" capable of organizing themselves on adsorbing surfaces exist in plasma, and that their length would be approximately 4.3 mµin round figures,instead of 4.0 mµ for the serum. The area occupied in the plane of adsorption by one individual molecule is, however, smaller than that occupied by the "serum molecule," thus indicating a marked structural difference between the two, the "plasma molecule" being narrower but longer than the "serum molecule." This difference may be due either to a different orientation accompanied by an increase in one of the dimensions, or else to an actual difference in structure with respect to the main axis, resulting in a decrease in the mean diameter of the "serum molecule" with an increase in the length of its main axis. The mass of the "plasma molecule" is about 6.3 per cent larger than that of the "serum molecule, " in the case of rabbit serum.
THE SURFACE COMPOSITION OF THE TUBERCLE BACILLUS AND OTHER ACID-FAST BACTERIA
Authors: Mudd Stuart , Mudd Emily B. H. 
Published: June 2004

Acid-fast bacteria in the boundary surface between salt solution and a test oil (tricaprylin) are spontaneously wet and enveloped by the oil. This behavior contrasts with that of all other cells studied by the interfacial tension method.
Four strains of human tubercle bacillus and an atypical bovine strain are an exception to the first statement above. These have possessed stability in the saline-oil interface; this stability is slight, however, and not comparable with that of non-acid-fast bacteria.
Acid-fast bacteria subjected to prolonged extraction with alcohol show resistance to wetting by oil comparable to that of non-acid-fast bacteria. These "defatted" bacteria nevertheless retain their acid-fast staining properties. Acid fastness cannot then depend on the integrity of a surface membrane.
Study of the cataphoresis of acid-fast bacteria by Freund has rendered the presence of protein in the surface highly probable. We are forced then to regard the surface of acid-fast bacteria as complex, containing at least lipoid and protein. Not improbably also carbohydrate is present.
CELL RESPIRATION STUDIES
Authors: Daland Geneva A. , Isaacs Raphael 
Published: June 2004

1. The oxygen consumption of blood of normal individuals, when the hemoglobin is saturated with oxygen, is practically zero within the limits of experimental error of the microspirometer used.
2. The oxygen consumed in a microspirometer by the blood of patients with chronic myelogenous leucemia with a high white blood cell count, and of one with leucocytosis from sepsis, was proportional to the number of adult polymorphonuclear neutrophils in the blood.
3. No correlation could be made between the rate of oxygen absorption and the total number of white blood cells in the blood, or the total number of immature cells, or the number of red blood cells, or the amount of oxyhemoglobin.
4. The blood of patients with chronic myelogenous leucemia continued to use oxygen in the microspirometer longer than that of normal individuals, and the hemoglobin, in the leucemic bloods, became desaturated even though exposed to air.
5. In blood in which the bulk. of the cells were immature and the mature cells few, the oxygen consumption was lower than in blood in which the mature cells predominated. The rate of oxygen consumption of the immature cells was relatively low as compared to the mature.
6. The slower rate of oxygen absorption by the immature leucocytes in chronic myelogenous leucemia as compared to the mature cells, places them, in accord with Warburg's reports, in the class of the malignant tissues in this respect rather than in the group of young or embryonic cells.
EFFECT OF HOST IMMUNITY TO A FILTERABLE VIRUS (VIRUS III) ON THE GROWTH AND MALIGNANCY OF A TRANSPLANTABLE RABBIT NEOPLASM
Authors: Pearce Louise , Rivers Thomas M. 
Published: June 2004

Experiments are reported in which were studied the course and character of a transplantable malignant neoplasm in normal rabbits and in rabbits immunized with a filterable virus, Virus III.
The disease which developed in immunized rabbits was extremely mild and much less severe than in normal animals.
The effect upon the tumor process displayed by Virus III immune rabbits in the direction of diminished malignancy is considered to be entirely non-specific in character, and the suggestion is made that it is accomplished through a more effective resistance of the host.