bluuebunny/crossref_metadata_2025 huggingface dataset:
UTERINE ADENOMATA IN THE RABBIT
Authors: Greene Harry S. N.
Published: June 2004

The behavior of a transplanted adenocarcinoma of the uterus of a rabbit has been studied through 12 serial generations in the anterior chamber of the eye and 6 serial generations in the testicle. The transplanted tumor is characterized by slow growth which is at first expansive and later invasive, by an ability to form more or less differentiated structures in response to different environmental conditions and by late metastasis. The endocrinological changes that distinguish animals bearing the spontaneous tumor do not occur in animals bearing the transplanted tumor.

Various experiments were undertaken in an attempt to discover the nature of the factors determining the characteristics of the spontaneous and of the transplanted tumor. It was found that successful transplantation was followed by a phase during which animals were refractory to reinoculation. The results of transplantation into the eyes of animals with spontaneous tumors suggested the existence of a similar phase during the early development of the tumor but the number of observations was not sufficiently numerous to warrant definite conclusions.
ORGAN WORK AND ORGAN WEIGHT
Authors: Walter Florence , Addis T.
Published: June 2004

1. The ratios between the rates of growth of the body and of the heart, kidneys, and liver are approximately uniform between 40 gm. body weight and the body weight at maturity in the albino rat. The male and female hearts grow at 0.75 times the rate of growth of the body, the male kidneys at 0.717 times, the female kidneys at 0.648 times, and the liver at 0.838 times the rate of growth of the body as a whole.

2. Formulas for the prediction of organ weight from body weight were derived from the data on 1591 albino rats kept under constant conditions.

3. A series of experiments in which dietetic and metabolic variables were introduced into otherwise constant conditions showed that the heart weight was not affected by diet, and that both kidney weight and weight of liver protein (used as a measure of effective liver size) varied in the direction of change in the protein content of the diet. Decrease in rate of metabolism induced by thyroidectomy and increase in metabolism following the administration of thyroxin led to a corresponding fall and rise of heart, kidney, and liver protein weight. These results were confirmed in experiments on fasted rats with the exception that under these conditions thyroidectomy did not appreciably decrease liver protein weight relatively to fasted controls. Increase in organ metabolism due to dinitrophenol had no effect on organ weight.

4. When experimental changes alter the composition of the body with respect to fat or water, the comparison of experimental and control organ weights in terms of any one function of body weight is fallacious.

5. Conditions that change kidney weight usually change liver protein weight in the same direction and roughly to the same degree. The possible meaning of two exceptions to this rule is discussed.

6. The observations made are regarded as supporting the hypothesis that, after weaning, change in the weight of the heart, kidney, and liver protein is determined mainly by change in the amount of work done by these organs.
STUDIES ON THE MECHANISM OF IMMUNITY IN TUBERCULOSIS
Authors: Lurie Max B.
Published: June 2004

1. Tuberculous and vaccinated rabbits and guinea pigs mobilize mononuclear phagocytes at the site of a non-specific inflammation with greater rapidity than do normal animals, just as they respond to tubercle bacilli.

2. The succession of cells that characterizes inflammation in general is accelerated in allergic rabbits and guinea pigs in response to non specific irritants.

3. The pH at the site of reinfection with tubercie bacffli in immun ized rabbits and guinea pigs and at the site of a non-specific inflammation in the latter is slightly lower than in a similar site in a normal animal.

4. No constant relation was found between the mobifization of mononuclears and the hydrogen ion concentration at the site of inflammation.

5. The rate of mitotic and amitotic division of mononuclears in allergic rabbits and guinea pigs in response to non-specific irritants is greater than in normal animals.

6. Mononuclears derived from actively tuberculous or vaccinated guinea pigs exhibit greater in vitro phagocytic capacity for carbon particles than mononuclears obtained from normal animals.

7. Mononuclears of tuberculous rabbits ingest more staphylococci than the phagocytes of the same type originating from normal animals.

8. Mononuclears originating from actively tuberculous rabbits and guinea pigs exhibit greater in vitro phagocytic capacity for tuberde bacilli than mononuclears obtained from normal animals.

9. The enhancement of the phagocytic capacity for tubercie bacilli afforded mononuclears by vaccination with a bacillus of low virulence is lower, and of questionable significance.

10. The increased phagocytic activity of mononuclears derived from tuberculous or vaccinated rabbits and guinea pigs for tubercie bacilli and for non-specific particulate matter occurs in media containing sera derived from normal and from tuberculous individuals.

11. The more rapid mobilization of mononuclears by immunized animals in response to specific as well as non-specific irritants is associated with their increased physiological activity.

The significance of this enhanced activity conferred by the tuberculous process on the mesenchyme cells is discussed in relation to the mechanism of immunity to tuberculosis and other phenomena.
THE MODE OF ACTION OF SULFANILAMIDE ON STREPTOCOCCUS. II
Authors: Gay Frederick P. , Clark Ada R. , Street Julia A. , Miles Dorothy W.
Published: June 2004

The precise mode of therapeutic action of sulfanilamide on streptococcus can be arrived at only by considering the sum total of factors that inhibit or favor the natural growth of the microorganism under the experimental conditions that obtain, whether in vivo or in vitro. Too sweeping conclusions have hitherto been drawn from the study of a single variable factor, such as an unfavorable temperature or the absence or presence of peptone. We have attempted here to analyze the factors that have hitherto been recognized and some new ones, but particularly the relationship of these factors to one another.

The result obtained on adding sulfanilamide to the streptococcus in the test tube is usually bacteriostasis and not complete destruction of even small numbers of bacteria. This is on the condition that the suspending medium is a favorable one for the growth of the microorganism; the more growth-promoting the medium is the less the bacteriostasis. If, on the other hand, the medium is too poor, or one that in itself inhibits growth, the addition of sulfanilamide may lead to sterilization of the culture.

The conditions for growth of the streptococcus in the body of the rabbit or mouse, depend on the strain of bacteria used, but are on the whole favorable. Defence, however, in the form of phagocytosis by both polymorphonuclear and by mononuclear cells is attempted even in the susceptible animal. When sulfanilamide is used to treat such an animal, or when sulfanilamide-grown (inhibited) streptococci are employed, phagocytosis is pronounced, whether studied in the test tube or in the animal body. In the rabbit the delay by sulfanilamide and resultant increased phagocytosis by polymorphonuclears allows mononuclear cells to accumulate and recovery may result.

Sulfanilamide not only does not completely destroy the streptococcus but does not even impair its innate virulence. It acts upon the streptococcus not only by inhibiting growth but by a temporary inhibition of hemotoxin formation, but only under certain conditions. The drug does not neutralize hemotoxin already formed. No significant effect of sulfanilamide on the formation of leucocidin or fibrinolysin by streptococcus has been evident in our experiments.

Sulfanilamide differs in one important respect from other drugs that are destructive either in the test tube or actually in the body, for protozoa and bacteria. Protozoa fix or adsorb arsenicals and acriflavine that kill them variably in vitro and in vivo. Streptococci fix both gentian violet and acriflavine, which dyes have marked destructive action in the test tube but are less effective in vivo. Sulfanilamide is not diminished at all by contact in vitro with large masses of streptococci, nor does the action of this drug render the microorganism more capable than untreated cocci to adsorb gentian violet or acriflavine, or to be destroyed by these highly bactericidal substances.
STUDIES ON EASTERN EQUINE ENCEPHALOMYELITIS
Authors: King Lester S.
Published: June 2004

After inoculation with equine encephalomyelitis virus by various routes, guinea pigs were sacrificed at early stages, before symptoms were apparent. The brains were studied histologically, with serial sections; all lesions were noted, and subjected to topographical analysis. Nine cases are presented in detail.

With any given mode of inoculation the distribution of lesions varied very widely from one instance to another. In some cases, affected regions bore a striking and definite anatomical relationship to each other. These distributions can be explained only by the assumption that the anatomical pathways played some rôle in the spread of the virus. In other instances lesions were present in areas, the anatomical connections of which were entirely normal. Attention is called to the frequency of lesions in the neocortex, with intact subcortical centers. Such distribution is held to render nerve spread extremely improbable. The only satisfactory explanation of such random distributions is by direct passage of virus from the blood stream into the brain tissue. There is no histological difference between lesions which result from blood spread and those resulting from nerve spread.
STUDIES ON THE SENSITIZATION OF ANIMALS WITH SIMPLE CHEMICAL COMPOUNDS
Authors: Landsteiner K. , Chase M. W.
Published: June 2004

Experiments are described on the latency period in sensitization to poison ivy and on the time necessary for the agent to remain in contact with the skin. The chief matter of investigation concerned the manner in which the whole skin becomes sensitive following treatment at a particular site, and especially whether this is effected by way of the epidermis.

Two methods were used to interrupt the continuity of the skin, one by cutting through both skin and the underlying thin muscular layer, the other by removing a strip of skin so as to spare the skin muscle. These procedures led to different results when poison ivy extract was applied to the areas thus isolated. In the first case, sensitization was mostly prevented, whereas with the second method generalized hypersensitiveness occurred almost uniformly.

An explanation is to be found in the severance of the lymph vessels lying on the surface of the muscular layer, pointing to the necessity of a free lymph passage. On the other hand the experiments prove that general sensitization is not dependent upon maintaining the integrity of the skin around a treated area.

An inhibition of sensitization by incisions extending through the panniculus carnosus was seen to some extent in anaphylactic sensitization with protein antigens, namely when sufficiently small amounts were employed.
STUDIES ON A BACTERICIDAL AGENT EXTRACTED FROM A SOIL BACILLUS
Authors: Dubos René J.
Published: June 2004

A Gram-positive, spore-bearing, aerobic bacillus, capable of lyzing the living cells of many Gram-positive microbial species, has been isolated from soil.

Cultures of this soil bacillus in peptone media release during autolysis a soluble agent which exerts a bactericidal effect on all the Gram-positive microorganisms so far tested, and inactivates their glucose dehydrogenases. It also inhibits the growth of the susceptible species in culture media.

Several of the Gram-positive species undergo lysis when incubated with the bactericidal agent. It appears however, that lysis is only a secondary process, due to the autolytic enzymes of the susceptible cells, and that it follows upon some other primary injury caused by the active agent.

The bactericidal agent is ineffective against all the Gram-negative bacilli so far tested.
STUDIES ON A BACTERICIDAL AGENT EXTRACTED FROM A SOIL BACILLUS
Authors: Dubos René J.
Published: June 2004

In the first paper of this series, a description was given of a cell-free extract, obtained from autolysates of a particular strain of a soil bacillus, which selectively inhibits the growth of all the Gram-positive microorganisms so far tested, and exerts on them a bactericidal effect in vitro.

In the present study it is shown that the same agent protects white mice against infection with large numbers of virulent pneumococci. It also exerts a curative effect when administered to mice several hours after injection of the infecting organisms.

The degree of protection afforded, and the minimal effective dose of bactericidal agent, are approximately the same for all virulent pneumococci, irrespective of type specificity.

The bactericidal agent is entirely ineffective against infection with virulent Friediänder bacilli (type B). This agrees with the fact that the agent does not affect Gram-negative bacilli in vitro.

The protective action exerted by the bactericidal agent against experimental pneumococcus infection depends upon the same mechanism which determines its bactericidal effect in vitro.
THE SIMULTANEOUS OCCURRENCE OF THE VIRUSES OF CANINE DISTEMPER AND LYMPHOCYTIC CHORIOMENINGITIS
Authors: Dalldorf Gilbert
Published: June 2004

A particular strain of canine distemper, long maintained by serial passage in dogs and ferrets was found to contain the virus of lymphocytic choriomeningitis in addition to that of distemper.
A MOUSE TEST FOR MEASURING THE IMMUNIZING POTENCY OF ANTIRABIES VACCINES
Authors: Webster Leslie T.
Published: June 2004

1. A quantitative practical mouse test is described for measuring the immunizing potency of antirabies vaccines.

2. Virulent virus, injected intraperitoneally as a vaccine, immunized mice within 10 days and for a period of at least 9 months. Demonstrable neutralizing antibodies accompanied this immunity. Virus given subcutaneously failed to immunize as effectively. The margin between immunizing and infecting dose of vaccine was small.

3. Commercial vaccines containing virulent virus prepared for the treatment of man gave results similar to those obtained with laboratory virus.

4. Commercial vaccines inactivated with phenol and prepared for the treatment of man in general failed to immunize mice. None contained virulent virus. The phenolized preparation from one commercial firm, however, as also the chloroformized preparation from another, immunized mice consistently when given intraperitoneally in quantities approximating 5 times that advocated per gm. of body weight in man.

5. Commercial canine vaccines inactivated with phenol proved non-virulent and failed to immunize mice.

6. Commercial canine vaccines inactivated with chloroform (Kelser) proved non-virulent but capable of immunizing mice provided a single intraperitoneal injection of 2 to 5 times that prescribed for dogs per gm. of body weight was given.

7. Chloroformized vaccines proved irritative to the peritoneum of mice.
HEPATIC INJURY ON A NUTRITIONAL BASIS IN RATS
Authors: György Paul , Goldblatt Harry
Published: June 2004

In forty-eight rats kept on a basal diet deficient in the vitamin B complex and supplemented with vitamin B1 and riboflavin or with vitamin B1, riboflavin and vitamin B6, various pathological changes in the liver were observed. These changes were characterized mainly by parenchymatous and fatty degeneration, focal and massive necrosis, hyperemia and hernorrhage and, in some of the rats, by perilobular and condensation fibrosis. Addition of yeast or Peters' eluate (yeast extract) regularly prevented this hepatic injury. On the basis of the evidence obtained, it is assumed that the liver changes are of nutritional origin and should be correlated to deficiency of a part of the vitamin B2 complex.
RÔLE OF INBORN RESISTANCE FACTORS IN MOUSE POPULATIONS INFECTED WITH BACILLUS ENTERITIDIS
Authors: Webster Leslie T. , Hodes Horace L.
Published: June 2004

1. Under conditions in which mouse typhoid is allowed to spread naturally among herds of mice comprised of different proportions of individuals of innately high or low susceptibility: (a) 85 to 95 per cent of the innately susceptible succumb to mouse typhoid in contrast to less than 5 per cent of the innately resistant, regardless of whether either constitutes 25, 50, or 75 per cent of the population respectively. (b) The surviving population is therefore comprised largely of individuals known at the outset to be innately resistant. These resistants are, nevertheless, apt to have become infected and to harbor mouse typhoid bacilli in their spleens and feces.

2. Under conditions in which recruits are added to surviving populations comprised chiefly of innately resistants among which mortalities have practically ceased: (a) Mouse typhoid infection spreads to both innately resistant and susceptible recruits. (b) Mortality from mouse typhoid is limited almost exclusively to the innately susceptible recruits and is "sporadic" or "epidemic" in character according to the numbers and proportion of susceptibles added. (c) Innately resistant recruits remain well unless subjected to some non-specific hazard, such as heat or overcrowding, in which case both they and the susceptibles succumb in proportions similar to their relative numbers in the population.

3. It was plain that survivors are almost exclusively the individuals known at the outset to have been innately resistant.

4. There was no tendency for known susceptibles to become immunized through herd exposure at epidemic times, at postepidemic times in which the dosage of mouse typhoid bacilli was relatively small, nor at repeated short intervals. Finally, susceptibles given repeated, known, sublethal doses of mouse typhoid bacilli or St. Louis encephalitis virus by a natural route failed to develop immunity against a subsequent test dose.
THE PRODUCTION OF KIDNEY ANTIBODIES BY INJECTION OF HOMOLOGOUS KIDNEY PLUS BACTERIAL TOXINS
Authors: Schwentker Francis F. , Comploier Frank C.
Published: June 2004

Rabbits injected with emulsions of homologous kidney to which staphylcoccus or streptococcus toxins had been added produced complement fixing antibodies which reacted with both rabbit kidney and brain. By absorption tests it was demonstrated that the sera contained at least two antibodies, one specific for kidney, the other non-specific. Similar kidney antibodies were found in the blood of a majority of patients with scarlet fever but in only a few normal persons. The possibility that a similar or related antibody may be concerned in the etiology of scarlatinal nephritis is discussed.
A CULTURE FLASK FOR THE CIRCULATION OF A LARGE QUANTITY OF FLUID MEDIUM
Authors: Lindbergh C. A.
Published: June 2004

An apparatus has been developed which permits the cultivation of a large number of tissue fragments in a large quantity of culture medium. The tissue fragments are cultivated in a thin layer of well oxygenated and constantly circulating medium.
STUDIES ON A BACTERICIDAL AGENT EXTRACTED FROM A SOIL BACILLUS
Authors: Dubos René J. , Cattaneo Carlo
Published: June 2004

A cell-free extract of cultures of an unidentified soil bacillus, which exerts a bactericidal effect on Gram-positive microorganisms, has been described in previous reports; the first active preparations which were obtained were found to contain a protein precipitable at pH 4.5. It is shown in the present report that the bactericidal agent can be obtained in an active form free of protein. The new purified preparations retain all the activity of the original material, both in vitro and in vivo.
THE PASSAGE OF PROTEINS FROM THE VASCULAR SYSTEM INTO JOINTS AND CERTAIN OTHER BODY CAVITIES
Authors: Bennett Granville A. , Shaffer Morris F.
Published: June 2004

1. Experiments designed to study, in the rabbit, the passage of foreign proteins from the blood stream into synovial fluid and to compare such passage with that taking place into the aqueous humor, spinal fluid, and urine are described.

2. Crystalline egg albumin and horse serum proteins regularly appeared in the knee joints within short periods of time following their intravenous injection.

3. These proteins also appeared promptly in the aqueous humor but in lower concentrations. In the spinal fluid they appeared only rarely and in minimal amounts.

4. Crystalline egg albumin was readily eliminated from the body via the urine. It was also removed rapidly from the knee joint and anterior chamber of the eye.

5. Horse serum proteins appeared only occasionally in the urine. Their concentration in the blood serum remained relatively high for several days.

Their increased concentration in the joint fluids in the longer experiments indicates that the rate of entrance exceeded the rate of removal.

6. Foreign proteins of the type employed were all found in the joint fluids in higher concentrations than they were in the other body fluids examined.

7. The possible significance of this study with respect to normal joint physiology and to certain abnormal joint conditions has been commented upon.
THE VIRULENCE OF GROUP C HEMOLYTIC STREPTOCOCCI OF ANIMAL ORIGIN
Authors: Seastone C. V.
Published: June 2004

A non-antigenic mucoid polysaccharide similar to that described by Kendall, Heidelberger, and Dawson was isolated from group C hemolytic streptococci. A simple method for its quantitative estimation is described.

By means of this quantitative method, as well as by the direct isolation of the carbohydrates, the size and persistence of capsules in young cultures of various strains have been related to the non-antigenic mucoid polysaccharide.

Similarly, invasiveness in different strains has been related to the mucoid polysaccharide. Data indicating the non-haptene nature of this material are presented.

An autolytic process, accelerated by bile, is involved in the loss of capsular material from young streptococci.
THE SPECIFICITY OF KERATEINE DERIVATIVES
Authors: Pillemer L. , Ecker E. E. , Martiensen E. W.
Published: June 2004

Carboxymethyl, α-carboxyethyl-, α-carboxy-n-propyl-, α-carboxyisopropyl-, α-carboxy-n-butyl, α-carboxyisobutyl, α-carboxyamyl-, benzyl-, and ß-phenylethylkeratemes were prepared from the parent protein, reduced keratin or kerateine. Chemical analysis disclosed that the various compounds differed in their isoelectric points and solubilities depending on the nature of the substituent group introduced. In general, it was found that in so far as could be determined, nearly all of the available sulfhydryl groups were substituted, while no detectable substitution of the free amino groups of the proteins occurred.

The results of the serologic studies revealed that the kerateine derivatives acquired a new immunologie character dependent on the nature of the introduced determinant group. Inhibition tests confirmed the results obtained. Evidence was also produced to show that the grouping

See PDF for structure

may play a rôle in some of the reactions observed.
ELECTROPHORETIC PATTERNS OF NORMAL AND PATHOLOGICAL HUMAN BLOOD SERUM AND PLASMA
Authors: Longsworth Lewis G. , Shedlovsky Theodore , MacInnes Duncan A.
Published: June 2004

The electrophoretic patterns of a series of normal and pathological human sera and plasmas have been obtained using the schlieren scanning method. From these patterns the mobilities and concentrations of the electrophoretically distinct protein components have been computed. The mobilities fall into five well defined groups corresponding to albumin, α, ß, and γ globulins, and fibrinogen. The concentrations of the different components in pathological sera have been compared with those in normal sera, and the following tentative generalizations may be made. The albumin/globulin ratios for pathological sera have been consistently lower than those for normal sera. The values of the α globulin/albumin ratio for the sera of the febrile patients studied were high, the average value being over twice the normal value. The γ globulin/albumin ratios for aplastic anemia and rheumatic fever sera were also above normal. Certain pathological conditions, notably nephrosis, were accompanied by large increases in a γ globulin. There is evidence that, in part at least, this consists of a labile lipo-protein.
EXPERIMENTAL PRODUCTION OF DIGESTIVE TRACT ULCERATIONS
Authors: Penner Abraham , Bernheim Alice Ida
Published: June 2004

We have attempted to reproduce in animal experiments a group of pathological findings which we have observed to be associated with shock. In order to simulate the compensatory vasomotor reactions occurring in shock, we have utilized the intraperitoneal injection of adrenalin hydrochloride in dogs, cats, rabbits and guinea pigs. That the effect of adrenalin hydrochloride when injected by this route is of long duration has been shown by the prolonged hyperglycemia which it produces.

Our experiments have resulted in the production of a lesion in the digestive tract which is identical in the gross with those which we observed in our human material. The histological changes, however, have been found to differ from those encountered in the latter. These differences have been noted to occur only in the dog and cat, where the initial changes take place in the mucosa, and the alterations in the submucosa appear secondary to these. In the rabbit and guinea pig the histogenesis of the lesions is identical with that observed in man, the lesions first manifesting themselves in changes in the submucosa, congestion, edema and hernorrhage. Only later are similar changes seen in the mucosa, progressing finally to necrosis and ulceration.

The cause of the histological differences has been found in the presence of arteriovenous anastomoses which occur in the submucosa in the case of the dog and cat and in the mucosa in the case of the rabbit, guinea pig and man.

We have pointed out that variations in blood flow through the intestinal wall may result from the short circuiting of the blood through the arteriovenous anastomoses. This, associated with the vasoconstriction known to occur in shock, may if severe and prolonged, result in necrosis of the intestinal wall. We have experimentally reproduced the same lesion by the injection of adrenalin, which acts in a similar way.

The experimentally produced anatomical changes offer additional evidence in support of the clinical occurrence of a vasospasm which is of sufficient severity and duration to cause tissue necrosis.
A METHOD FOR THE STUDY OF INDUCED INTERFERENCE WITH TRANSPLANTABLE TISSUE GROWTH
Authors: MacFadyen Douglas A. , Murphy James B.
Published: June 2004

1. A design of experiments and technical procedure is described for the study of interference with transplantable tissue growth by test agents. The methods are guided by the principle of randomization and are based on the pairing of test and control in each host.

2. A system of analysis, employing well known statistical measures, is applied to results obtained with these methods and shows that they lead to consistently reproducible results.

3. A simple analytical method is proposed for correlating results obtained with different kinds of transplantable tissue in different strains of animals.

This method is based on the condensation of an extended frequency distribution of events in control series of cases into a three category array of a normal frequency distribution. The three categories of test action are the inhibitory, the ineffectual, and the accelerative.
A STUDY OF PASSIVE IMMUNITY TO MENINGOCOCCUS INFECTION IN THE CHICK EMBRYO
Authors: Buddingh G. John , Polk Alice D.
Published: June 2004

1. 14 day old chick embryos are protected against subsequent meningococcus infection through the amniotic route by the intravenous administration of an homologous antiserum produced in hens, by a commercial concentrated polyvalent meningococcus antiserum and by a commercial meningococcus antitoxin.

2. Titrations of the different antisera indicate that the homologous and commercial polyvalent sera have approximately the same protective value and are much more effective than the commercial antitoxin. The titrations also show that the chick embryo is a sensitive indicator of the amount of antibodies present in a given amount of serum.

3. The mechanism of the protective action of the antisera is not apparent from these experiments except that in the treated embryos there is a relative inhibition of the growth and presumably a neutralization of the injurious products of the meningococci.
THE MASKING EFFECT OF EXTRAVASATED ANTIBODY ON THE RABBIT PAPILLOMA VIRUS (SHOPE)
Authors: Kidd John G.
Published: June 2004

The foregoing experiments have shown that the causative virus is usually "masked" in the large, disorderly, fissured and inflamed papillomas of cottontails when antiviral antibody is present in quantity in their blood, though virus can be recovered as a rule from the smaller, discrete, well ordered papillomas of these rabbits, almost irrespective of the amount of antibody in the blood of the individuals bearing them. Other findings are described which indicate that the masking of the virus in the large fissured growths is due to serum antibody present in them as result of exudation or hemorrhage, which neutralizes the virus when the growths are extracted or preserved in vitro. The local conditions that favor extravasation of serum (and the accumulation of antibody) prevail as a rule in the large, confluent growths arising after virus has been sown broadcast on scarified skin, but to lesser extent or not at all in the discrete papillomas that occur naturally or as result of tattoo inoculation.

The state of affairs is notably different in the papillomas of domestic rabbits. The virus is regularly masked in these, and usually masked completely, even when there is little antibody in the blood and the local conditions do not favor its extravasation into the growths. The findings indicate that something other than antibody is primarily responsible for the masking in this species.
THE EFFECT OF DIETARY PROTEIN ON THE COURSE OF NEPHROTOXIC NEPHRITIS IN RATS
Authors: Farr Lee E. , Smadel Joseph E.
Published: June 2004

Acute nephritis of medium severity, affecting both glomeruli and tubules, was produced in rats by injections of anti-rat-kidney serum, given on 3 consecutive days.

The course of the nephritis was markedly influenced by the type of diet which was fed. Rats tended to recover promptly from the induced nephritis when a low protein-high carbohydrate diet was given. On the other hand, in nephritic rats maintained on a medium protein diet the nephritis almost invariably became chronic and half the animals died of renal insufficiency during the 10½ months of observation. Finally none of the rats which received a high protein-low carbohydrate diet recovered from the acute renal injury; all developed chronic progressive nephritis and the majority died of renal failure after some months.
CHEMICAL STUDIES ON BACTERIAL AGGLUTINATION
Authors: Alexander Hattie E. , Heidelberger Michael
Published: June 2004

1. The quantitative, absolute methods of agglutinin and precipitin analysis previously developed for antipneumococcus sera have been shown to be applicable to horse and rabbit anti-influenza type B sera and plasmas.

2. With the aid of these methods and improved immunization schedules the antibody content of the rabbit sera has been increased five to ten times.

3. The method recommended for the purification of rabbit antipneumococcus antibody has also been found applicable to rabbit anti-influenza type B sera.
STUDIES ON EASTERN EQUINE ENCEPHALOMYELITIS
Authors: King Lester S.
Published: June 2004

In mice affected with equine encephalomyelitis, the first pathological disturbance in infant animals is an inflammatory reaction, which is usually less pronounced in adult animals. A characteristic type of parenchymal damage appears to be independent of the inflammation. In such foci of injury there is initially a vacuolation of intercellular tissue. Neurones in such areas are at first intact, later show cytoplasmic changes, and finally nuclear alterations. Complete disintegration of tissue and all its elements may be the end result.
A CRYSTALLINE PRESSOR SUBSTANCE (ANGIOTONIN) RESULTING FROM THE REACTION BETWEEN RENIN AND RENIN-ACTIVATOR
Authors: Page Irvine H. , Helmer O. M.
Published: June 2004

1. Renin reacts with renin-activator to form a strong pressor substance which is heat-stable, water- and alcohol-soluble, fluorescent, acid-stable, and alkali-labile. It is a reducing substance and is destroyed by strong oxidizing substances. It forms crystalline salts with oxalic and picric acids. The color reaction for arginine is the only one found to be strongly positive. It is suggested that this substance be called angiotonin.

2. Angiotonin produces a sharp, immediate rise in arterial pressure when injected intravenously. Pithing and dissipation of the anesthetic appear to increase the response. Tachyphylaxis occurs, in contrast to renin, only after many single doses.

3. The responses to adrenaline and angiotonin do not parallel one another. Cocaine, atropine, and stilbestrol do not affect the pressor action of angiotonin. Suprarenalectomy in brief experiments is also without effect.

4. Maximal amounts of angiotonin result when the proportion between renin and activator is roughly 3 to 100. This is not a stoichiometric relationship in the chemical sense. The temperature suitable for good yields is about 38°C., and the time of reaction from 10 to 20 minutes.

5. Renin destroys angiotonin when incubated with it.

6. Angiotonin causes marked contraction of intestinal segments of rabbits without reducing their rhythmic motion. It sensitizes the intestine to further doses of angiotonin and alters the intestine such that renin-activator contracts it. Angiotonin also constricts the vessels of a rabbit's ear perfused with blood or Ringer's solution.
APPARATUS FOR FREEZING AND DRYING VIRUS IN LARGE QUANTITIES UNDER UNIFORM CONDITIONS
Authors: Bauer Johannes H. , Pickels Edward G.
Published: June 2004

1. The apparatus described was designed for the desiccation under uniform conditions of large quantities of yellow fever virus in the frozen state.

2. Several hundred cubic centimeters of virus material, distributed in small containers, have been desiccated simultaneously to almost complete dryness and with no appreciable loss of infectivity.

3. Good keeping qualities of the virus activity are insured by sealing the containers either while evacuated or after filling with dry nitrogen.
THE SIGNIFICANCE OF THE SYNOVIAL VILLUS AND THE CILIARY PROCESS AS FACTORS IN THE LOCALIZATION OF BACTERIA IN THE JOINTS AND EYES OF RABBITS
Authors: Angevine D. Murray , Rothbard Sidney
Published: June 2004

1. Histological examination of sections of the eyes and joints of large numbers of rabbits injected with hemolytic streptococci has clearly demonstrated that when arthritis or cyclitis occurs, the synovial villi and ciliary processes are the most frequent and usually the primary sites of inflammation.

2. By special methods for demonstration of bacteria, it has been shown that bacteria which found lodgement in either an eye or a joint were demonstrable first in the vessels of ciliary processes or synovial villi.

3. A localized synovitis or iridocyclitis is brought about by the localization of bacteria in the synovial villus and ciliary process.

4. These experiments, which give a clearer insight into the pathogenesis of infectious arthritis and iritis, explain why both may occur in association with certain infectious diseases.
STUDIES ON THE MOLECULAR WEIGHT OF DIPHTHERIA TOXIN, ANTITOXIN, AND THEIR REACTION PRODUCTS
Authors: Pappenheimer A. M. , Lundgren H. P. , Williams J. W.
Published: June 2004

Purified diphtheria antitoxic horse pseudoglobulin has been prepared which is homogeneous by sedimentation, diffusion, and electrophoresis. Immunologically, however, the preparation contains only 43.5 per cent antitoxin specifically precipitable by toxin. The inactive pseudoglobulin remaining after specific precipitation was found to have the same physical and chemical properties as the original antitoxic pseudoglobulin. Although the molecular weight of antitoxin is the same as that of the normal horse serum globulins, the electrophoretic mobility does differ from those normally present.

The molecular weight of diphtheria toxin is 70,000 and of antitoxin is 150,000.

From ultracentrifuge studies on the two reactants and on mixtures of toxin and antitoxin in the soluble inhibition zones, the average molecular composition of the specific floccules at certain reference points throughout the equivalence zone and the maximum "valence" of toxin and antitoxin with respect to each other have been calculated.

The significance of the results has been discussed in relation to antigen-antibody reactions in general and a possible explanation for the exceptional behavior of the toxin-antitoxin reaction in the region of excess antitoxin has been suggested.
BLOOD PLASMA PROTEIN PRODUCTION AND UTILIZATION
Authors: Madden S. C. , Finch C. A. , Swalbach W. G. , Whipple G. H.
Published: June 2004

When blood plasma proteins are depleted by bleeding with return of the washed red blood cells (plasmapheresis) it is possible to bring dogs to a steady state of hypoproteinemia and a uniform plasma protein production on a basal low protein diet. These dogs are clinically normal. Introduction of variables into their standardized life gives insight into the production of plasma protein.

Casein retested as the basal protein in the ration may show high yield of plasma protein, equal to 33 per cent of the protein fed. This equals the potency of liver protein (17 to 33 per cent) and approaches the utilization of plasma protein by mouth (40 per cent).

Zein has no effect upon plasma protein regeneration but when it is supplemented with cystine, tryptophane, lysine, and glycine, there is a doubling of the liver basal plasma protein production and a retention of the fed protein nitrogen. Threonine does not modify the above reaction.

Liver protein supplemented with cystine, leucine, glutamic acid, and glycine in the basal diet yields double the amount of new formed plasma protein compared with liver alone. This combination is then as potent as plasma protein itself when given by mouth—40 per cent utilization. Tyrosine or lysine, arginine, and isoleucine do not modify the above responses.

Methionine is not as effective as cystine in supplementing gelatin and tyrosine to produce plasma protein.

Cystine, leucine, and glutamic acid appear to be of primary importance in the building of new plasma protein in these experiments.

Plasma protein formation is dependent upon materials coming from the body reserve and from the diet. Given an exhaustion of the reserve store there is very little plasma protein produced during a protein fast (3 to 6 gm. per week). A turpentine abscess does not modify this fasting plasma protein reaction.

Homologous plasma given by vein will promptly correct experimental hypoproteinemia due to bleeding. It will maintain nitrogen equilibrium and replenish protein stores. Even during hypoproteinemia plasma protein may promptly pass out of the circulation to supply body needs for protein. Perhaps the most significant concept which derives from all these experiments is the fluidity of the body protein (including plasma protein)—a ready give and take between the protein depots—a "dynamic equilibrium" of body protein.
THE RESTORATION OF LOST ORGAN TISSUE
Authors: Addis T. , Lew W.
Published: June 2004

1. When half of the total kidney, suprarenal, ovarian, or testicular mass is removed the rate of growth of the remaining half is independent of the rate of growth of the organ at the time of removal.

2. The removal of half of the prostate, or seminal vesicular tissue, or of one uterine horn is not followed by any appreciable growth of the part that remains.

3. The rate of restoration of renal, ovarian, testicular, and suprarenal tissue after removal of half of these organs is at first very rapid, but quickly decelerates and at about 40 days after the removal there is a complete cessation of growth.

4. In none of these organs is all the lost tissue restored. In the testicle the 50 per cent left increases to 56 per cent and in the kidney, suprarenal, and ovary to 70 per cent of the original amount before operation.
A DISTINCTIVE SUBSTANCE ASSOCIATED WITH THE BROWN-PEARCE RABBIT CARCINOMA
Authors: Kidd John G.
Published: June 2004

The serologically active substance of the Brown-Pearce tumor, a complement-fixing antigen, differs notably from certain other tissue antigens (the Wassermann, Forssman, and organ- and species-specific tissue haptens, for example) in the fact that it is not effective after alcoholic extraction of the tissue containing it. Like many of the proteins and viruses it is in-activated upon heating to 65°C. for 30 minutes; and, like them as well, its activity is lost upon treatment with acid (to pH 4.5 or lower) or alkali (to pH 11.5 or higher).

Filtration and centrifugation experiments disclosed the fact that the antigen of the Brown-Pearce tumor passed readily through collodion membranes with average pore diameters of 383 mµ and more, but was retained completely by those with average pore diameters of 348 mµ and less. It was thrown down completely or almost completely upon centrifugation at 20,000 R.P.M. for one hour. The findings indicate that the Brown-Pearce tumor antigen has a large and nearly uniform particle size and weight,—as large as that of many of the viruses. They differentiate it sharply from the generality of "soluble antigens.rdquo;

Upon direct comparison, the complement-fixing antigen of the Brown-Pearce tumor was found to be similar in a number of its general traits to the serologically active substance of the virus-induced papillomas of rabbits, which in turn is intimately associated or identical with the virus responsible for the papillomas. Extracts of the Brown-Pearce tumor containing the serologically active substance in quantity have given rise to no lesions, however, upon injection into normal or tarred rabbits.

The significance of the findings is discussed.
SOME CONSTITUENTS OF ELEMENTARY BODIES OF VACCINIA
Authors: Smadel Joseph E. , Lavin George I. , Dubos René J.
Published: June 2004

Treatment of elementary bodies of vaccinia with dilute solutions of sodium hydroxide resulted in the extraction of certain soluble materials accounting for half of the dry weight of the virus. Elementary bodies contained about 0.4 per cent inorganic phosphorus, practically all of which occurred in the form of a nucleoprotein containing thymus nucleic acid. In addition, a substance was recovered that reacted with S antibodies. From past experience one is led to believe that S antigen, as ordinarily encountered, is a protein which is not in combination with nucleic acid.
A LATENT VIRUS IN NORMAL MICE CAPABLE OF PRODUCING PNEUMONIA IN ITS NATURAL HOST
Authors: Horsfall Frank L. , Hahn Richard G.
Published: June 2004

1. A virus capable of producing fatal pneumonia in mice has been isolated repeatedly from the lungs of certain apparently healthy mice. Not all mice carry the virus. It was obtained only from mice supplied by three breeders although mice from eight different sources were studied.

2. The virus was avirulent as it occurred in normal mouse lungs and became virulent only after serial mouse lung passage. It was strictly pneumotropic for mice and produced pneumonia when given intranasally but showed no evidence of infection when given by other routes. The virus was non-infectious for ferrets and did not become pathogenic for this species after numerous serial passages. It was also non-pathogenic for rabbits, guinea pigs, rhesus monkeys, voles, deer mice, skunks, wood-chucks, opossums, and Syrian hamsters.

3. All strains of the virus which have been tested have been immunologically identical, as indicated both by cross immunity and cross neutralization tests in mice.

4. The virus was antigenic both in mice and in rabbits and was readily differentiated from viruses of human influenza and of swine influenza by means of either cross immunity or cross neutralization tests.

5. The virus was also neutralized by about 30 per cent of normal human sera tested.

6. The virus was extremely labile, and suspensions prepared in saline or broth became inactivated within a few hours at room temperature. The addition of normal horse serum to the virus suspensions, however, exerted a definite stabilizing effect.

7. Ultrafiltration results indicated that the virus particles have a diameter of about 100 to 150 millimicrons.

8. Evidence is presented which indicates that this virus is different from other viruses which various investigators have found in normal mouse lungs.
GROWTH INHIBITION BY SUBSTANCES IN LIVER
Authors: Brues Austin M. , Subbarow Y. , Jackson Elizabeth B. , Aub Joseph C.
Published: June 2004

Certain tissue constituents inhibitory to cell growth, extracted from liver, are described. The findings indicate that inhibitory material is adsorbed to colloids in the native state and is freed from them by alcohol extraction. One inhibitor, ethanolamine, has been isolated. This substance differs in its biological properties from the bulk of the inhibitory material present in liver. Progress in purification of other inhibitors is described, and it is shown that inhibition by these extracts is not correlated with surface activity or with the presence of pigmented constituents.

The inhibitors have common properties which suggest that they are of physiological significance in the regulation of growth: action over a wide range of concentrations at which other cell functions are undamaged; reversibility of action; presence in adult liver in concentrations near those which inhibit growth in vitro, while in embryo liver they are found only in much lower concentrations.
STUDIES OF THE INFECTIOUS UNIT OF MYXOMA
Authors: Parker Robert F.
Published: June 2004

The virus of infectious myxoma of rabbits behaves on inoculation into the skin as if infection were initiated by a single viral particle.