bluuebunny/crossref_metadata_2025 huggingface dataset:
PROPAGATION OF VACCINIA VIRUS IN THE RABBIT FETUS
Authors: Gallagher Fred W. , Woolpert Oram C.
Published: June 2004

1. A method is described for propagation of bacteria-free vaccinia virus in the rabbit fetus.

2. For the production of severe generalized infection, affording a high yield of virus, the following conditions were found to be favorable: the use of 24 day fetuses, a virus dosage of 10,000 adult rabbit skin units, injection into multiple sites, and an incubation period of 4 days in utero.

3. Under these conditions the virus was found to disseminate widely in the infected fetus, being recoverable particularly from liver, lungs, brain, skin, placenta, and kidney.

4. Under varied conditions of virus dosage, fetal age, and incubation period, all grades of reaction were observed in the fetus, ranging from the mildest infection, with only an occasional small lesion demonstrable, to generalized vaccinia with pocks in nearly every organ of the body, and often death.

5. It was shown that the virus could be carried in serial passage through fetuses. A series of 27 such passages was made by using fetal skin for subinoculation at each transfer. Similarly, two other strains of the virus were evolved in shorter series of transfers by using respectively fetal brain and fetal liver as the subinocula.

6. The passage strains maintained their identity and titer, as judged by the intradermal inoculation of adult rabbits. However, these strains underwent a significant reduction in their capacity to infect by the scarification method, and the lesions induced by intradermal inoculation were much milder than those produced by the parent strain. None of the passage strains manifested properties characteristic of the so called neurovaccine strain, despite the frequent use of intracerebral inoculation in the fetuses.

7. In explanation of the reduction of virulence of the passage strains, it is suggested that a given suspension of virus may be considered as consisting of particles of varying degrees of virulence, and that when cultivation is carried out in highly susceptible tissues a relative overgrowth of the less virulent elements is permitted, so that apparent attenuation results.
ELECTROPHORETIC STUDIES ON ELEMENTARY BODIES OF VACCINIA
Authors: Shedlovsky Theodore , Smadel Joseph E.
Published: June 2004

Electrophoretic studies were made on vaccine virus, collodion particles, and glass particles suspended in 0.01 molar buffer solutions at pH 7.9, in which the moving boundary method was used. In some experiments, uncoated particles were used; in others, particles were coated with proteins and then resuspended in the buffer solution after a washing; in still others, an excess of protein which had been used to coat the particles was included in the buffer medium.

Streaming boundaries were obtained with all dilute suspensions of particles in solutions containing no soluble protein instead of the flat ones usually observed with the Tiselius moving boundary technique. This boundary artifact was suppressed by maintaining a density gradient of sufficient magnitude in association with the moving boundary to counteract the tendency of endosmotic flow. This was done partially by increasing the concentration of the particles in the suspensions, and almost completely by retaining an excess of soluble-coating substance in the solutions containing the particles.

The mobility of elementary bodies of vaccinia corresponds to that found for the heat-stable (S) antigen. This value was not altered by drying, heating, ether extraction, or simple washing, but was materially increased by treatment with the surface active detergent (duponol) which presumably altered the nature of the surface of the virus particles.

Collodion particles coated with the heat-stable antigen of vaccinia had the same mobility as elementary bodies under comparable conditions.

Glass particles coated with normal rabbit serum moved at the rate of albumin, the fastest serum component in the buffer solutions used. However, both collodion particles and vaccine virus moved at a somewhat slower rate when they were similarly coated and measured in the presence of an excess of serum in the solutions. This was probably due to adsorption of a small amount of one of the slower components (globulin) of rabbit serum on the surface of the particles. Simple washing after treatment seemed to remove the coating of serum proteins, at least in part, from both collodion particles and elementary bodies of vaccinia.
OBSERVATIONS ON MIXTURES OF ELEMENTARY BODIES OF VACCINIA AND COATED COLLODION PARTICLES BY MEANS OF ULTRACENTRIFUGATION AND ELECTROPHORESIS
Authors: Smadel J. E. , Pickels E. G. , Shedlovsky T. , Rivers T. M.
Published: June 2004

It has been shown experimentally that mixtures of two types of particles, namely, elementary bodies of vaccinia and collodion particles coated with protein, sediment with a single boundary in the analytical centrifuge. Such mixtures have been shown to develop one or two boundaries on electrophoresis in the Tiselius apparatus, depending on the type of coating on the surface of the collodion particles. When covered with the heat-stable soluble antigen of vaccinia, collodion particles migrate in the electrical field at the same rate as elementary bodies. On the other hand, if they are coated with a component of normal rabbit serum, they migrate at a different rate.

The estimation of purity of preparations of virus by means of data obtained by ultracentrifugation and electrophoresis is discussed.
THE PLACENTAL TRANSMISSION OF ANTIBODIES IN THE SKIN SENSITIVE TYPE OF HUMAN ALLERGY
Authors: Sherman William B. , Hampton Stanley F. , Cooke Robert A.
Published: June 2004

1. Quantitative studies of the skin-sensitizing antibodies, blocking antibodies, and hemagglutinins in sera of allergic human beings have been made.

2. A comparison of 12 maternal and the 12 corresponding cord sera by the method of passive transfer showed the human placenta to be impermeable to skin-sensitizing antibodies.

3. Direct skin tests and passive transfer studies of 6 infants at the ages of 3 to 6 months showed negative reactions to the antigens to which their mothers were sensitive.

4. The blocking antibody present in the sera of hay fever patients after treatment with pollen extract injections was also demonstrated in the cord sera. The apparent placental transmission of this antibody gave further evidence that it was distinct from the skin-sensitizing antibody. Infant sera obtained at the ages of 3 to 6 months showed no evidence of this immune antibody.

5. The cord sera from 4 of these cases were shown to contain the same isoagglutinins as the maternal sera, showing that the placentas were permeable to these antibodies. The mothers and their offspring reacted alike to Schick testing.

6. Typhoid agglutinins were demonstrated in maternal and cord sera of an adult who previously received injections of triple typhoid vaccine, whereas the serum of the corresponding infant at the age of 3 months failed to show agglutinins.
A STUDY OF THE NEUROTROPIC TENDENCY IN STRAINS OF THE VIRUS OF EPIDEMIC INFLUENZA
Authors: Francis Thomas , Moore Alice E.
Published: June 2004

The demonstration by Stuart-Harris that the W.S. strain of epidemic influenza virus can induce a fatal nervous disease in mice has been confirmed.

In contrast, however, no previous period of adaptation to chick embryonic brain was required. By serial brain to brain passages in mice originally inoculated with the virus cultivated in the usual chick embryo culture medium a fatal disease, essentially meningeal in character, is produced.

The Melbourne strain has been similarly enhanced while other strains have failed to reveal any neurotropic tendencies.

The evidence indicates that the neurotropic characteristic is present in the two strains as an inherent quality which is quantitatively heightened and does not represent the acquisition of a property not previously present.
A STUDY OF QUANTITATIVE CHANGES OF THE SHOPE RABBIT PAPILLOMA VIRUS AT THE SITE OF INOCULATION IN THE SKIN OF THE COTTONTAIL AND DOMESTIC RABBIT
Authors: Packalén Thorolf
Published: June 2004

By excising after varying intervals the site of inoculation of the rabbit skin injected intracutaneously with the Shope papilloma virus and titrating its virus content, it has been shown that demonstrable active virus disappears from the skin within approximately 24 hours. The disappearance of most of the virus within such a short time as 15 to 60 minutes makes a transportation of virus from the site of inoculation as a responsible factor unlikely. The rate of disappearance seems to be the same both in the domestic and in the cottontail rabbit.
REDUCTION OF ARTERIAL BLOOD PRESSURE OF HYPERTENSIVE PATIENTS AND ANIMALS WITH EXTRACTS OF KIDNEYS
Authors: Page Irvine H. , Helmer O. M. , Kohlstaedt K. G. , Fouts P. J. , Kempf G. F.
Published: June 2004

1. Extracts of kidneys have been prepared containing a substance which lowers arterial blood pressure for prolonged periods in patients with essential and malignant hypertension, and in hypertensive dogs and rats.

2. Several different chemical procedures are proposed for the preparation of the extract. The best one has not been decided upon.

3. The quantity of original fresh whole kidney required to yield enough extract to lower blood pressure from hypertensive levels (200 mm. Hg mean pressure) to normal levels is roughly 600 to 900 gm. in dogs within 4 to 8 days. In hypertensive patients the yield from 700 to 1000 gm. daily for several weeks may be necessary.

4. Lowering of the blood pressure too rapidly in animals results in a shock syndrome which may be fatal. If overdosage is avoided, no appreciable rise in blood urea nitrogen occurs, nor do other signs of toxicity appear.

5. Lowering of blood pressure to nearly normal levels has been accomplished in 60 hypertensive dogs, and in some of these it has been allowed to rise and was again reduced as many as five times. Similar results have been obtained with hypertensive rats.

6. Six patients with essential hypertension have been treated resulting in prolonged reduction of blood pressure. Clinically the patients appear improved.

7. Five patients with malignant hypertension have been treated, with reduction of the blood pressure in all instances. One patient was treated despite urea clearance of 5 per cent of normal. His blood pressure was sharply reduced, but death in uremia occurred. The second patient also exhibited sharp reduction of pressure and died after treatment was discontinued. The other three are much improved after treatment, as indicated by increase in vision and mental activity, loss of dyspnea, improvement in the electrocardiogram, etc.

8. The length of time the blood pressure remains lowered varies greatly in both animals and man. The trend is usually upwards after discontinuing treatment for 4 to 6 days.

9. Increasing experience with this treatment suggests that it is of value in the management of hypertension, but it is yet in the experimental stage.
CIRRHOSIS OF THE LIVER CAUSED BY EXCESS DIETARY CYSTINE
Authors: Earle David P. , Victor Joseph
Published: June 2004

1. Cystine fed to young albino rats as 10 per cent of the diet resulted in: (a) Portal hemorrhagic necrosis, resembling eclampsia, within 3 or 4 days. (b) A high mortality rate. (c) Fatty infiltration of hepatic cells in all rats surviving the initial acute lesion. (d) Cirrhosis of the liver in rats surviving more than 2 weeks.

2. 5 per cent dietary cystine produced marked fatty infiltration of the liver, followed by portal hemorrhagic necrosis. Cirrhosis was present in one of the two rats on the diet for 6 weeks.

3. The livers of rats fed 5 or 10 per cent cystine diets followed by the McCollum stock diet, showed evidence of residual cellular damage, and of regeneration as shown by mitotic figures.

4. In this series of 30 rats on excess dietary cystine, a renal lesion was found in only one case.
STUDIES ON EXPERIMENTAL HYPERTENSION
Authors: Goldblatt Harry , Weinstein Harry , Kahn Joseph R.
Published: June 2004

By means of a silver chain attached to a silver ring around the main renal artery, intermittent renal arterial occlusion, up to 30 minutes daily, was practiced for as long as 5 months in unilaterally nephrectomized dogs. This did not result in the development of persistently elevated blood pressure. Persistent moderate constriction of the renal artery of such animals by a silver clamp, after intermittent temporary occlusion had failed to affect the blood pressure, produced the usual rise of blood pressure, without accompanying significant impairment of renal excretory function. When the renal artery accidentally became persistently constricted to a great degree, or actually occluded, or if occlusion was deliberately produced by continuous pulling of the chain, hypertension and renal insufficiency (the malignant phase) quickly developed. The results do not lend support to the view that brief daily periods of renal ischemia from intrarenal vasospasm, or from any other cause, can produce persistent hypertension of renal origin.
A VIRUS FROM CASES OF ATYPICAL PNEUMONIA
Authors: Eaton Monroe D. , Beck M. Dorthy , Pearson Harold E.
Published: June 2004

From the lungs of two fatal cases and from the sputum of two non-fatal cases of atypical bronchopneumonia, a psittacosis-like virus was isolated by direct intranasal inoculation of mice. Intraperitoneal injection of the same human material into mice gave negative results.

The virus has a relatively high virulence for mice by intranasal or intra-cerebral inoculation, but does not kill after intraperitoneal inoculation.

Its virulence for Java ricebirds is low and it fails to produce a carrier state in mice and birds.

Two cases showed an increase in complement-fixing antibodies to the new virus and to psittacosis.

The virus is antigenically related to the viruses of meningopneumonitis and psittacosis by complement fixation and by active immunity tests in mice.
QUANTITATIVE CHEMICAL STUDIES ON COMPLEMENT OR ALEXIN
Authors: Heidelberger Michael
Published: June 2004

1. A quantitative micro method, conforming to the criteria of analytical chemistry, is proposed for the estimation of complement, or its combining component or components, in milligrams per milliliter instead of in the customary relative and variable volume units.

2. Data are given showing the range of accuracy and reproducibility of the new method.
THE NATURAL HISTORY OF HUMAN POLIOMYELITIS
Authors: Sabin Albert B. , Ward Robert
Published: June 2004

1. Studies on a large number of tissues obtained from fatal cases of human poliomyelitis have revealed that the virus is distributed predominantly in two systems: (a) certain regions of the nervous system, and (b) the alimentary tract.

2. Poliomyelitis virus was demonstrated in the walls of the pharynx, ileum, and only once in those of the descending colon, while the contents of the descending colon regularly contained the virus.

3. The presence of virus in the walls of the alimentary tract appears to be the result neither of generalized dissemination of the virus nor of secondary centrifugal spread, but rather that of primary localization or portal of entry.

4. In the absence of evidence of any demonstrable centrifugal spread to peripheral collections of nerve cells (e.g., in the superior cervical sympathetic ganglia, suprarenals, salivary glands), the presence of virus in the abdominal sympathetic plexus of one case may be indicative of at least one pathway of centripetal virus progression.

5. The absence of demonstrable virus in the nasal mucosa, olfactory bulbs, and anterior perforated substance suggests that neither the upper respiratory tract nor the olfactory pathway were affected in the cases of human poliomyelitis studied in the present investigation.
CHEMICAL STUDIES ON BACTERIAL AGGLUTINATION
Authors: Henriksen Sverre D. , Heidelberger Michael
Published: June 2004

1. Application of the quantitative agglutination procedure to hemolytic streptococci and their antisera is shown to yield values indicative of the antibody content of the antisera in weight units.

2. Estimations are given of type-specific and group-specific antibody in a number of antisera.

3. An incomplete analysis is given of the antigenic components and antibodies involved in the agglutination.

4. Adaptation of the experimental conditions to a simple qualitative type determination of hemolytic streptococci is suggested.
RENAL HYPERTENSION PRODUCED BY AN AMINO ACID
Authors: Bing Richard J. , Zucker Marjorie B.
Published: June 2004

Acute renal hypertension is produced by the injection of the amino acid dopa (l-dihydroxyphenylalanine) into the partially or completely ischemic kidney of the cat.

Evidence is presented suggesting that the rise in blood pressure following the injection of dopa is caused by its conversion into hydroxytyramine, a pressor amine.

Kidneys with normal blood flow fail to transform dopa into a pressor substance.
THE COMPLEMENT FIXATION TEST IN THE DIAGNOSIS OF VIRUS INFECTIONS OF THE CENTRAL NERVOUS SYSTEM
Authors: Casals J. , Palacios R.
Published: June 2004

A specific complement fixation test can be obtained in various central nervous system virus infections by using as antigens emulsions of infected brain tissue, freezing and thawing the brain emulsion, and then centrifuging it in an angle head centrifuge at 3500 R.P.M. for 1 hour. The method has proved reliable in the case of rabies, St. Louis encephalitis, Japanese B encephalitis, lymphocytic choriomeningitis, Eastern equine encephalomyelitis, Western equine encephalomyelitis, louping ill, and spontaneous encephalomyelitis of mice (Theiler's disease).

The specificity of the reaction, regardless of the virus involved, requires different temperatures of inactivation of the sera according to animal species: 56°C. for guinea pig, 60°C. for mouse, and 65°C. for rabbit and dog sera, all heated for 20 minutes. For human sera a temperature of inactivation of 60°C. also for 20 minutes has been adopted; at this temperature the reaction is in general specific.

Complement-fixing antibodies in high titre were found in the sera of rabbits, guinea pigs, mice, and dogs immunized with rabies virus.

Complement-fixing antibodies were present in high titre in sera drawn from two persons 8 years after an attack of louping ill, from five persons 2½ years after an attack of Eastern equine encephalomyelitis, and from two persons 2½ years after Western equine encephalomyelitis. In cases of St. Louis encephalitis and lymphocytic choriomeningitis, complement-fixing antibodies have been found shortly following infection but not after long periods.
THE BACTERICIDAL ACTION OF SYNTHETIC DETERGENTS
Authors: Baker Zelma , Harrison R. W. , Miller Benjamin F. ,   With the Technical Assistance of Robert Wexler
Published: June 2004

1. The bactericidal action of a number of anionic and cationic synthetic detergents on four Gram-positive and three Gram-negative bacteria has been investigated.

2. Cationic detergents, as a group, were found to exhibit marked bactericidal effects on Gram-positive microorganisms and somewhat less pronounced action on Gram-negative organisms.

3. The anionic detergents were germicidal only against the Gram-positive organisms, and they were considerably less effective than the cationic compounds. Of the anionic detergents, the most active one was an alkyl sulfate derived from a branched-chain, secondary alcohol.

4. Correlations between bactericidal action and inhibition of bacterial metabolism, and also between bactericidal action and chemical structure of the detergents are discussed.
A FURTHER STUDY OF THE CROSS REACTION BETWEEN THE SPECIFIC POLYSACCHARIDES OF TYPES III AND VIII PNEUMOCOCCI IN HORSE ANTISERA
Authors: Heidelberger Michael , Kabat Elvin A. , Mayer Manfred
Published: June 2004

1. The cross reaction of the specific polysaccharide of Type VIII pneumococcus with Type III antipneumococcus horse serum has been studied quantitatively and found similar to the S III-anti-S VIII reaction.

2. Contrasted with the general similarity of the two-segment reaction curves were distinct qualitative and quantitative differences in the course and character of the reciprocal reactions with respect to each segment.

3. These differences could be interpreted in terms of the known chemical differences between the specific polysaccharides of the two types. A minimum molecular weight of 62,000 was calculated for S III and 140,000 for S VIII.

4. It was also found possible to fractionate the Type VIII antibody into portions characteristic of each segment of the cross reaction curve. At least three different kinds of Type III and Type VIII anticarbohydrates were identified.
THE ENDURING PARTNERSHIP OF A NEOPLASTIC VIRUS AND CARCINOMA CELLS
Authors: Kidd John G.
Published: June 2004

The V2 carcinoma—a transplanted rabbit cancer derived originally from a virus-induced papilloma and carrying in masked or altered form the virus primarily responsible for it—was propagated in five successive groups of animals all previously hyperimmunized against the papilloma virus. The cancer grew as well in the hyperimmunized hosts as in normal animals implanted during the same months; and serological tests, made when the tumor was eventually returned to ordinary hosts, proved that the virus was still associated with the carcinoma cells: it had increased to the usual extent as the tumor grew in the hyperimmune animals.

The continued increase of the neoplastic virus during propagation of the V2 carcinoma in hyperimmunized hosts contrasts sharply with the elimination of certain extraneous passenger viruses when the tumors they ride upon are grown in hosts previously immunized against them. The facts as a whole would seem to warrant a distinction between the enduring partnership of a neoplastic virus and carcinoma cells on the one hand and the casual association of passenger viruses with tumor cells on the other.
INFLUENCE OF AGE ON SUSCEPTIBILITY OF MICE TO ST. LOUIS ENCEPHALITIS VIRUS AND ON THE DISTRIBUTION OF LESIONS
Authors: O'Leary James L. , Smith Margaret G. , Reames Harold R.
Published: June 2004

1. Young mice are more susceptible than older mice to the virus of St. Louis encephalitis inoculated intraperitoneally, but with virus inoculated intracerebrally or intranasally, there is no significant age difference in susceptibility. The greatest change in the resistance to the virus inoculated intraperitoneally occurs between the 2nd and 3rd weeks of life.

2. The distribution of the lesions of St. Louis encephalitis in the C.N.S. of young and of old animals following intraperitoneal inoculation indicates that the virus may reach the brain either by the ascending pathway from the spinal cord or by the olfactory pathway irrespective of the age of the animal. However the ascending pathway is most frequently concerned.

3. The distribution of lesions does not offer evidence that the virus enters the C.N.S. of young animals directly from the blood stream following intraperitoneal inoculation.

4. Although widespread lesions occur earlier in the C.N.S. of young mice than in that of older mice inoculated intraperitoneally with large doses of virus, this fact is not satisfactorily explained by assuming the more rapid increase of the virus in the C.N.S. of young animals, since the latter are not more susceptible to virus inoculated directly into the brain.

5. The observations can be explained by the hypothesis that a greater amount of virus survives and reaches the portals of the C.N.S. in young animals following intraperitoneal inoculation and that this is an important factor in the influence of age on susceptibility to the virus.
SYNTHESIS OF INOSITOL IN MICE
Authors: Woolley D. W.
Published: June 2004

It has been shown that mice are able to synthesize inositol. This synthesis was not observed when pantothenic acid was absent from the diet. Cultures from the intestinal tract of animals which exhibited spontaneous cure of alopecia yielded microorganisms which synthesized much more inositol than did organisms isolated in the same fashion from the tracts of mice that had become hairless. Some observations on the distribution of free and combined inositol have been made and it has been shown that several biological materials contain combined inositol. It has been found that deficiency of inositol can develop even when inositol is present in the diet if pantothenic acid is omitted.
STUDIES ON LYMPHOGRANULOMA VENEREUM
Authors: Rake Geoffrey , Jones Helen P.
Published: June 2004

Making use of the fact that the cells of the yolk sac of the developing embryo are readily infected with the agent of lymphogranuloma venereum and that the virus bodies can be readily observed in these cells because of the structure of the latter, the development of this agent has been followed at short intervals. It has been found to go through a regular cycle of development similar to that described for psittacosis in the spleen and less fully for lymphogranuloma venereum in the brain of infected mice. The development as observed microscopically can be shown to run parallel to changes in the infective titre of the yolk sac as tested in other eggs.
ON THE MECHANISM OF SPECIFIC PRECIPITATION
Authors: Boyd William C.
Published: June 2004

A study of the precipitability by the appropriate antisera of 34 different haptens, containing from one to six reactive groups, leads to the conclusion that the possibility of framework ("lattice") formation is neither necessary nor sufficient for specific precipitation, but that instead precipitation depends upon the reduction, by mutual neutralization of polar groups of antibody and antigen (or hapten) and mechanical blocking off of polar groups of closely neighboring molecules of antibody, of the solubility of the complex below the point at which it can remain in solution. The decisive factors appear to be the number of polar groups of the antigen (hapten) left free, and the distance separating the different reactive groups, which determines the amount of steric hindrance exerted by one antibody molecule on another. No hypothesis is offered as to how these primary insoluble aggregates unite with each other to produce the larger aggregates which are finally observed.
A SEROLOGICAL CLASSIFICATION OF VIRIDANS STREPTOCOCCI WITH SPECIAL REFERENCE TO THOSE ISOLATED FROM SUBACUTE BACTERIAL ENDOCARDITIS
Authors: Solowey Mathilde
Published: June 2004

A total of 108 strains of viridans streptococci from subacute bacterial endocarditis, and 99 strains from human throats and extracted teeth have been studied, and approximately two-thirds of all the strains so far have been differentiated into a number of serological groups. The similarity between strains from these sources is evident from the fact that approximately 50 per cent of the reacting strains from each source fall into two groups I and II, and that three groups I, II, and IV, contain streptococci from both sources in approximately the same distribution. Fifteen vaginal strains of viridians streptococci failed, with the exception of one strain, to react with groups I–IV of the endocarditis serums. More than three-fourths of the strains from both sources were Streptococcus salivarius as determined by Sherman's criteria. However, no correlation between the biochemical and serological classification could be made.

It may be concluded that the viridans streptococci are amenable to classification by serological methods. The results so far obtained do not indicate a serological difference between strains of viridans streptococci isolated from subacute bacterial endocarditis, and those isolated from human throats and extracted teeth. The greater definitive value of serological methods in the identification of a particular strain is indicated.
RECIPROCAL TRANSMISSION TESTS WITH INFECTIOUS CATARRH OF CHICKENS, MICE, AND RATS
Authors: Nelson John B.
Published: June 2004

Infectious catarrh of chickens (fowl coryza of slow onset) was not transmissible to mice or rats by nasal instillation of the specific coccobacilliform bodies. Exudates were also inactive in both rodents on foot pad injection.

The infectious catarrhs of the mouse and the rat were reciprocally transmissible by the nasal injection of exudates or tissue cultures of the respective coccobacilliform bodies and by direct contact. Exudates and cultures also produced an arthritic reaction in both hosts on foot pad injection.

The coccobacilliform bodies of mouse catarrh were innocuous in chickens on nasal instillation, whereas those of rat catarrh were established locally but were maintained for only two passages.

In the opposite host each of the two rodent forms of infectious catarrh reproduced the typical features of the naturally acquired disease, a highly fatal pneumonia being characteristic of the mouse but not of the rat.
EXPERIMENTAL INFECTION OF THE CHICK EMBRYO WITH THE VIRUS OF PSEUDORABIES
Authors: Bang Frederik B.
Published: June 2004

The chick embryo responds to experimental infection with the virus of pseudorabies with a disease pattern simulating the natural infection. Virus lesions of the membrane are followed by infection of all tissues of the central nervous system.

Fixed strains produce a hemorrhagic destruction of the central nervous system of the embryo, which is referable to destruction of blood vessel endothelium. Field strains lack the hemorrhagic tendency, but infect the brain when inoculated on the membrane.

Neutralization of the virus by specific hyperimmune serum can be demonstrated by inoculation on the membrane.

The reaction of the embryo to the virus varies with the age of the embryo. This is reflected both in the membranal lesion and in the subsequent encephalitis.
EFFECTS OF EXCESS DIETARY CYSTEIC ACID, dl-METHIONINE, AND TAURINE ON THE RAT LIVER
Authors: Earle David P. , Smull Katharine , Victor Joseph
Published: June 2004

1. Cysteic acid fed to albino rats as 12.5 to 15 per cent of the McCollum stock diet caused portal necrosis and cirrhosis of the liver within 2 weeks. Concentrations of cysteic acid of 6.25 per cent or less in the diet produced no liver lesions within 2 weeks.

2.dl-Methionine fed as 6.4 to 12.4 per cent of the McCollum stock diet or of a low protein, low fat diet, resulted in severe atrophy of the liver cells but no cirrhosis of the liver.

3. Taurine fed as 1 to 10 per cent of the McCollum stock diet produces no liver lesions.

4. For reasons discussed in the paper, it is concluded that the liver necrosis and cirrhosis produced by cystine and cysteic acid are not dependent upon the S-S linkage of the cystine, the oxidation of the sulfur, the formation and excretion of large amounts of urinary sulfate, or the presence of an amino group separated from a sulfur molecule by a 2 carbon chain.
INDUCED RESISTANCE OF THE CENTRAL NERVOUS SYSTEM TO EXPERIMENTAL INFECTION WITH EQUINE ENCEPHALOMYELITIS VIRUS
Authors: Morgan Isabel M. , Schlesinger R. Walter , Olitsky Peter K.
Published: June 2004

1. Neutralizing antibody to equine encephalomyelitis virus was found in the spinal fluid of rabbits sufficiently vaccinated with active or formalin-inactivated virus. Antibody was specific for the Western or for the Eastern virus.

2. Neutralizing capacity of spinal fluid was equivalent to that of a 1/300 dilution of serum of the same animal, and was of the same order of magnitude as that of perfused brain of a vaccinated animal.

3. Vaccinated rabbits which showed antibody in the spinal fluid resisted intracerebral or intracisternal injection of active virus. This immunity was specific, i.e., there was no cross-reaction between the Eastern and Western virus after vaccination with formalin-inactivated virus. On the other hand, lack of antibody in the spinal fluid, even when antibody was demonstrable in the undiluted serum, was associated with lack of cerebral resistance.
SEROLOGICAL REACTIONS OF PROTEIN FILMS AND DENATURED PROTEINS
Authors: Rothen A. , Landsteiner K.
Published: June 2004

Films of several proteins, hen ovalbumin, horse and human serum albumins, and globulins were found to combine specifically with antibodies, showing that the reactions can take place independently of the structure which secures the compact shape of the protein molecule. Serum globulin films differed from ovalbumin in that they lost their reactivity when kept on the water surface. Species specific reactions were observed with films of serum albumin and suitably diluted antisera, and likewise in the customary precipitin tests in which immune sera for denatured hen ovalbumin were tested against ovalbumin of other species. Specific fixation was also observed upon exposing monolayers of purified antibodies for pneumococci of Types I and III to the corresponding polysaccharides.
COAGULATION AND LIQUEFACTION OF SEMEN
Authors: Huggins Charles , Neal William
Published: June 2004

Certain specimens of human semen shorten the coagulation time of whole blood because of the presence of active thromboplastic agents, while other samples prolong its coagulation time. Human prostatic fluid in large amounts always delays or abolishes blood coagulation. The delay or absence of clotting is counteracted by adding calcium ions and is due to the large concentration of citrate in prostatic fluid and in some semens.

While most specimens of dog semen shorten the coagulation time of blood because of their thromboplastic activity, certain specimens render blood incoagulable or delay coagulation; in contrast to human semen, this adverse effect on coagulation is not overcome with calcium ions and is due to a different mechanism, the lysis of fibrinogen. The citrate content of dog prostatic fluid is small.

Human semen which has become liquefied does not contain thrombin or prothrombin, but fibrinogen and thromboplastic substances are present. Beef fibrinogen added to semen is destroyed by incubation for 18 hours, but added prothrombin and thromboplastic substances are still present after this treatment. Dog semen, in some instances, contains small amounts of thrombin.

The semens of man and dog contain a fibrinolysin for human blood which seems not to differ greatly from the fibrinolysin associated with hemolytic streptococci. The blood of the donor of prostatic fluid is susceptible to fibrinolysis by this fluid. However, the blood of persons with some diseases, is absolutely resistant to the action of seminal fibrinolysin. In how many diseases this happens has not yet been determined.

The semens of man and dog both contain an agent capable of inactivating fibrinogen, but in different amounts. This activity may be called fibrinogenase. Human semen is rich in fibrinolysin, poor in fibrinogenase; dog semen is rich in fibrinogenase, poor in fibrinolysin. These species differences, together with the fact that it is easy by appropriate dilution to retain the stronger proteolytic agent and eliminate the weaker one, imply that fibrinolysin and fibrinogenase are different entities.

Dog semen, and less constantly human semen, contain very small amounts of trypsin.

All of these proteolytic agents derive from the prostate gland; their secretion in prostatic fluid constitutes a hitherto undescribed function for the prostate gland.
STUDIES CONCERNING THE SITE OF RENIN FORMATION IN THE KIDNEY
Authors: Friedman Meyer , Kaplan Alex
Published: June 2004

1. The administration of tartrate to adult rabbits was found to produce in some of them, a profound and widespread necrosis of the proximal convoluted tubular epithelium without affecting the other portions of the nephrons.

2. The markedly damaged kidneys were found to be almost completely devoid of pressor substance (renin), indicating that in the mammalian kidney, the epithelium of the proximal convoluted tubules is concerned in the formation or storage of renin.
THE EFFECT OF SALICYLATES ON THE PRECIPITATION OF ANTIGEN WITH ANTIBODY
Authors: Coburn Alvin F. , Kapp Eleanor M.
Published: June 2004

1. Sodium salicylate modifies the precipitation of normal rabbit serum protein by sodium tungstate, and partially inhibits the precipitation of horse serum euglobulin by rabbit antiserum. Sodium salicylate added to a system containing crystalline egg albumin and its antibody partly prevents the formation of precipitate, the degree of inhibition being related to the concentration of salicylate.

2. Precipitation in the equivalence zone is more readily prevented by salicylate than precipitation in the region of antibody excess, the immune system becoming progressively less sensitive to the action of salicylate as the excess of antibody becomes larger.

3. Formed precipitates were partly dissolved following resuspension in the presence of salicylate.

4. The salicylate effect on immune precipitation is reversible, and appears to be due to inactivation of antibody.

5. Salicylate was more effective in preventing specific precipitation than other anions of a lyotropic series tested.
ISOLATION OF CHROMATIN THREADS FROM THE RESTING NUCLEUS OF LEUKEMIC CELLS
Authors: Claude Albert , Potter James S.
Published: June 2004

1. A method for the separation of chromatin threads from the resting nucleus of leukemic cells has been described.

2. The isolation of the chromatin strands was accomplished by purely mechanical means, and the separation, including extraction and purification in the centrifuge, required only about 1 hour.

3. Evidence is presented to show that the chromatin strands are morphologically related to the chromosomes, if not identical.

4. It seems probable that, by the present technique, chromatin strands can be obtained from different mammalian tissues for direct microscopical examination and biochemical analysis.
THE METABOLISM OF THE ISCHEMIC KIDNEY
Authors: Raska Sigwin B.
Published: June 2004

The consumption of oxygen by slices of kidney tissue of dogs made hypertensive by the Goldblatt technique was studied manometrically. The respiration of the ischemic kidney tissue was found to be much less than that of the normal kidney. Further, a marked reduction in oxidizing ability, as measured by the oxygen uptake and ammonia formation in the presence of the added amines and amino acids, tyramine, isoamylamine, dl-alanine, and l-aspartic acid, was observed.

Extracts of the kidneys were made and tested for amine oxidase, amino acid oxidase, and polyphenol oxidase activity by measuring the increased oxygen consumption and ammonia formation in the presence of the substrates listed above with the addition of l-epinephrine, histamine, and dl- and l-dihydroxyphenylalanine. The preparations from ischemic kidneys of dogs and rabbits showed much lower activity. Animals with varying degrees of constriction of the renal arteries and therefore varying degrees of renal ischemia were prepared and studied. The results with these animals suggested a direct relationship between the degree of renal ischemia and the decrease in oxidizing power of the tissue.

The product of the enzymic oxidation of tyramine was identified as p-hydroxyphenylacetaldehyde by isolation as the dinitrophenylhydrazone of p-hydroxyphenylacetaldehyde.
THE DISAPPEARANCE OF PHOSPHATASE FROM THE HYDRONEPHROTIC KIDNEY
Authors: Wilmer Harry A.
Published: June 2004

"Alkaline" phosphatase disappears or only remains in small amounts in the rabbit and rat kidney after periods of hydronephrosis of 2 to 5 days or more, following complete obstruction of the ureter. By the use of the Gomori-Takamatsu technique it has been possible to distinguish normally functioning from non-functioning cells, when by ordinary histologic stains the cells are indistinguishable.
STUDIES ON THE ANTIGENIC COMPOSITION OF GROUP A HEMOLYTIC STREPTOCOCCI
Authors: Lancefield Rebecca C.
Published: June 2004

1. Proteolytic enzymes destroy the type-specific M antigen of group A hemolytic streptococci not only when the M substance is contained in cell-free extracts but also when it is a component of the living cell.

2. The injection of enzyme-treated cultures into rabbits fails to induce the formation of M antibodies, but does result in the production of T antibodies and, therefore, provides a method of preparing anti-T sera free from M antibodies.

3. Exposure to these enzymes does not kill the bacteria. Virulence and the ability to form M substance are restored on subculture and animal inoculation.

4. The study of the effect of proteolytic enzymes on group A hemolytic streptococci provides new techniques for analyzing the antigenic composition of these microorganisms.
THE STABILITY OF INFLUENZA VIRUS IN THE PRESENCE OF SALTS
Authors: Knight C. A.
Published: June 2004

The stability of centrifugally purified PR8 influenza virus at pH 7 in 0.001, 0.01, 0.1, and 1.0 M phosphate buffers, in veronal and borate buffers, and in adjusted solutions of saline and distilled water was investigated. The results demonstrate that the stability of this virus can vary considerably at pH 7 depending upon the nature and concentration of the salts present. Borate, veronal, and phosphate buffers at a concentration of about 0.1 M showed almost equal ability to maintain virus activity over several weeks of time at 4°C. In many cases, it may prove inconvenient to use veronal buffer, however, because of the difficulty in determining protein concentration in its presence. The 0.1 M phosphate buffer has proved in tests not described here to be slightly more consistent in preserving virus activity than the borate and may, therefore, be considered slightly superior to the latter. It is apparent that unbuffered saline is a poor solvent for preserving virus activity regardless of pH. The activity of partially inactivated virus in distilled water and in saline solutions was increased ten to 1000 times by diluting such solutions with 0.1 M phosphate buffer. Some reactivation was also effected with veronal but not with borate buffers.
THE EFFECT OF SOME CHEMICALS ON PURIFIED INFLUENZA VIRUS
Authors: Knight C. A. , Stanley W. M.
Published: June 2004

A study was made of the effect of 0.05 and 0.5 N solutions of 20 different chemicals on the activity of purified PR8 influenza virus in 0.1 M phosphate buffer. It was found by tests in chick embryos and in mice that virus activity was destroyed by strong oxidizing agents such as iodine, by salts of heavy metals, by mercurochrome, by formaldehyde, and by the detergents phemerol, roccal, and sodium dodecyl sulfate. Reducing agents appeared to have little if any inactivating effect with the exception of 0.05 N ascorbic acid. At the concentrations tested, sulfathiazole sodium exerted only a weak inactivating effect. 0.5 N phenol inactivated the virus promptly, but solutions of the strength more commonly used for bactericidal purposes were only weakly virucidal. The virus appeared relatively unaffected by glucose, ammonium sulfate, calcium chloride, sodium thiosulfate, and arginine.
THE RÔLE OF THE MUCOID POLYSACCHARIDE (HYALURONIC ACID) IN THE VIRULENCE OF GROUP A HEMOLYTIC STREPTOCOCCI
Authors: Kass E. H. , Seastone C. V.
Published: June 2004

1. A quantitative turbidimetric method for the estimation of hyaluronidase activity, based on the ability of the enzyme to decrease the capacity of the polysaccharide to precipitate acidified protein has been developed. Two units of hyaluronidase, by this method, are equivalent to one viscosity-reducing unit.

2. Hyaluronidase added to a phagocytic system containing defibrinated human blood, immune or non-immune, greatly increases the rate of phagocytosis of group A streptococci. Phagocytosis of Type I pneumococci is not affected by hyaluronidase under the same conditions.

3. The bactericidal activity of non-immune blood against group A streptococci is increased by hyaluronidase; the activity of immune blood is, however, somewhat inhibited by the enzyme. Killing of pneumococci is not affected by the presence of the enzyme.

4. Mice can be protected against group A streptococcal infection by frequent treatment with 200 turbidity-reducing units of hyaluronidase; the protective action of the enzyme is removed by heating at 60°C. for 1 hour. Mice infected with Type I pneumococcus and treated with hyaluronidase die somewhat sooner than the untreated controls.
INTERFERENCE BETWEEN THE INFLUENZA VIRUSES
Authors: Ziegler James E. , Horsfall Frank L.
Published: June 2004

Reciprocal interference between influenza A, influenza B, and swine influenza viruses has been demonstrated in the chick embryo. Certain temporal and quantitative factors which influence the production of interference in this host-virus system have been studied. The implications of these observations in relation to the mechanism by which interference is produced are discussed.
STUDIES ON LYMPHOGRANULOMA VENEREUM
Authors: Rake Geoffrey , Jones Helen P.
Published: June 2004

Toxins, which resemble in most respects bacterial endotoxins, are associated with the agents of lymphogranuloma venereum, meningopneumonitis, and mouse pneumonitis as they grow in the yolk sac of the chick embryo. They are labile and are not readily separated from the bodies of the agent. They kill mice rapidly after intravenous, and in some cases after intraperitoneal, injection but the minimal lethal dose is relatively large and, in those freshly harvested yolk sacs which have been tested, has corresponded to about 36 million infective units. Characteristic lesions are produced in all mice except those which die very rapidly, and are found especially in the liver where necrosis of the midzone of the lobule occurs.

Antitoxic sera which are effective against a few lethal doses of the toxin can be produced in rabbits or chickens by using either toxin or toxoid as antigen. Such sera behave in a manner analogous to antiendotoxins against bacterial endotoxins and they do not neutralize by the law of multiple proportions. Antitoxic sera can also be obtained from human beings convalescent from at least one of these diseases. The toxins and antitoxins appear to be highly specific and they may offer a useful tool in distinguishing between different members of this closely interrelated group.
EXPERIMENTAL EPIDEMIOLOGY OF TUBERCULOSIS
Authors: Lurie Max B.
Published: June 2004

1. Hereditary resistance to attack by air-borne tubercle bacilli is distinct from the resistance to the ensuing disease.

2. One inbred rabbit family has little resistance to attack: by the microorganism but has considerable resistance against the ensuing disease.

3. Another inbred family has considerable resistance against attack by the tubercle bacillus but has little resistance against the ensuing disease.

4. Increasing concentrations of tubercle bacilli in the environment of the family of high genetic resistance to the disease increase the incidence of infection, accelerate the onset of the disease, and affect its essential character in proportion to the concentration of the microorganism.

5. Up to a certain concentration of tubercle bacilli in the environment of the families of low genetic resistance to the disease, increasing concentrations of the infectious agent also increase the incidence of the disease and accelerate its onset, although its anatomical character is always of a uniform rapidly progressive type. Beyond this concentration further increment of the infectious agent exercises no effect.