UTERINE ADENOMATA IN THE RABBIT : I. CLINICAL HISTORY, PATHOLOGY AND PRELIMINARY TRANSPLANTATION EXPERIMENTS.

83 cases of an adenomatous tumor of the uterine mucosa have been observed in a colony of rabbits during the past 4 years The results of a clinical and pathological study of the tumor, together with a description of transplantation experiments are included in the present report. The clinical histories of tumor bearing animals are similar in all cases. Discovery of the tumor is preceded by a long period of reproductive disturbance, and its subsequent course is one of slow, continuous growth which has terminated in death with metastasis in all animals held under observation for longer than 1 year.

JAPANESE B ENCEPHALITIS VIRUS: ITS DIFFERENTIATION FROM ST. LOUIS ENCEPHALITIS VIRUS AND RELATIONSHIP TO LOUPING ILL VIRUS.

1. Japanese B encephalitis virus, obtained from Japanese investigators, has proved virulent for mice and monkeys, confirming the reports from Japan. It has also been found virulent for monkeys when instilled intranasally and for sheep when introduced intracerebrally or intranasally.

THE COURSE OF VIRUS-INDUCED RABBIT PAPILLOMAS AS DETERMINED BY VIRUS, CELLS, AND HOST.

An experimental analysis of the factors responsible for the observed differences in the course of virus-induced papillomas of the rabbit has shown that some are referable to the virus, others to the cells, and yet others to host influences. The interplay of these factors affords enlightening illustration of the nature of the cell-virus relationship in virus-induced tumors. Retrogression of the rabbit papillomas appears to be consequent on a generalized resistance of host origin, elicited by and directed against the proliferating, virus-infected cells.

CALCULATIONS OF BIOELECTRIC POTENTIALS : II. THE CONCENTRATION POTENTIAL OF KCl IN NITELLA.

Cells of Nitella have been studied which behave differently from those described in earlier papers. They show unexpectedly large changes in P.D.

ISOLATION, CRYSTALLIZATION, AND PROPERTIES OF SWINE PEPSINOGEN.

1. A method is described for the preparation of pepsinogen from swine gastric mucosae which consists of extraction and fractional precipitation with ammonium sulfate solutions followed by two precipitations with a copper hydroxide reagent under particular conditions. Crystallization as very thin needles takes place at 10 degrees C.

THE ABSENCE FROM THE URINE OF PERNICIOUS ANEMIA PATIENTS OF A MOSQUITO GROWTH FACTOR PRESENT IN NORMAL URINE.

Extracts prepared from the urine of normal persons or patients with aplastic anemia or leukemia contain a substance, possibly flavine or a flavine compound, which under suitable conditions of test enhances the growth of larvae of the mosquito, Aëdes aegypti. This substance is lacking, or is present in much smaller amount, in extracts from the urine of pernicious anemia patients showing symptoms of the disease. Extracts from the urine of the same patients after adequate treatment contain as much of the substance as normal urine extracts.

HEPATIC DYSFUNCTION IN DOGS FED DIETS CAUSATIVE OF BLACK TONGUE.

1. The feeding to dogs of a diet lacking the vitamin B(2) (G) complex results in a lowered capacity of the liver to excrete intravenously injected bilirubin. 2.

EXPERIMENTAL SYPHILIS OF ORIENTAL ORIGIN: CLINICAL REACTION IN THE RABBIT.

Two oriental strains of T. pallidum of Chinese origin were compared with two well known occidental strains, the Nichols and the Zinsser-Hopkins, on the basis of the clinical reaction to infection in the rabbit. Four experiments were carried out, two each in Peiping and New York.

THE CARCINOGENIC EFFECT OF A PAPILLOMA VIRUS ON THE TARRED SKIN OF RABBITS : I. DESCRIPTION OF THE PHENOMENON.

The Shope papilloma virus elicits carcinomas forthwith, as well as papillomas in great variety, when it is distributed by way of the blood stream to the tarred epidermis of domestic rabbits. The phenomenon will be analyzed in succeeding papers with the aid of additional instances.

THE EFFECT OF FORMALDEHYDE ON PNEUMOCOCCI.

When used in low concentration, formaldehyde increases the rate of autolytic disintegration of pneumococci whereas in large concentrations it completely inhibits autolysis and preserves both the morphological and staining characteristics of the cells. Pneumococci treated with large concentrations of formaldehyde, then washed free of the antiseptic and resuspended in physiological solutions, rapidly undergo a change which renders them Gram-negative and smaller. The lysis is only partial, however, and is not accompanied by an actual disintegration of the cell.

TOXEMIA OF PREGNANCY IN THE RABBIT : II. ETIOLOGICAL CONSIDERATIONS WITH ESPECIAL REFERENCE TO HEREDITARY FACTORS.

No definite conclusions relative to the etiology of toxemia of pregnancy in the rabbit can be drawn from the evidence obtained to date, but certain findings are suggestive and will be investigated further in future studies. These findings suggest that the disorder in the rabbit is a generic variation of eclampsia in man. The incidence, clinical manifestations and pathological lesions indicate that the disorder is of hypophyseal origin and that the association with pregnancy is due to altered activity of that gland in the terminal stages of gestation.

THE INCREASED SUSCEPTIBILITY TO HEMOLYSIS BY INDOL IN DOGS FED DEFICIENT DIETS.

1. Indol is more hemolytic in the presence of a deficiency complex than when a normal diet is fed. 2.

INDUCED SUSCEPTIBILITY OF THE BLOOD TO INDOL.

1. Indol, orally administered, causes anemia when certain deficient diets are fed. 2.

THE HEMOLYTIC EFFECT OF INDOL IN DOGS FED NORMAL DIETS.

Indol is mildly hemolytic when fed to dogs taking normal diets.

INFLUENCE OF HOST FACTORS ON NEUROINVASIVENESS OF VESICULAR STOMATITIS VIRUS : IV. VARIATIONS IN NEUROINVASIVENESS IN DIFIERENT SPECIES.

Peripheral inoculation of vesicular stomatitis virus is constantly followed by myelitis or encephalitis in young mice, but not in young (or old) guinea pigs. The cause of this variation was elucidated by investigating the fate of the virus after inoculation by a number of different routes. Direct intracerebral injection of minimally infective amounts of virus was found to be equally fatal for young mice and young guinea pigs, indicating that the central nervous system as a whole was as easily injured by the virus in one species as in the other.

INFLUENCE OF HOST FACTORS ON NEUROINVASIVENESS OF VESICULAR STOMATITIS VIRUS : III. EFFECT OF AGE AND PATHWAY OF INFECTION ON THE CHARACTER AND LOCALIZATION OF LESIONS IN THE CENTRAL NERVOUS SYSTEM.

It will be well to restate the main problem at this point and to examine how far the accumulated data can help to elucidate it. The problem is this: Why are old mice generally resistant to all forms of peripheral inoculation of vesicular stomatitis virus when intracerebral injection is equally fatal for mice of all ages? The results of experiments in which the presence of virus was demonstrated by animal passage suggested that the reason can perhaps be found in (a) the different mechanisms of virus progression after intracerebral and peripheral injection, and (b) the development with age of localized barriers capable of halting the spread of virus (1, 2). The present study sought histological evidence for the nature of virus progression and for the changes observed in the older animals.

THE CONCENTRATION EFFECT WITH VALONIA: POTENTIAL DIFFERENCES WITH DILUTED POTASSIUM-RICH SEA WATERS.

The concentration effect with sea waters containing more than the normal amount of potassium has been studied in Valonia macrophysa. This was done by comparing the initial changes in P.D.

AN ULTRACENTRIFUGAL ANALYSIS OF CONCENTRATED STAPHYLOCOCCUS BACTERIOPHAGE PREPARATIONS.

Analytical observations have been made with the air ultracentrifuge on concentrated staphylococcus bacteriophage solutions and on these solutions inactivated by alkali, chymo-trypsin, and heat. All active solutions contain a homogeneous heavy component that sediments with a constant of s(20 degrees ) = ca. 650 x 10(-13) cm.

CONCENTRATION AND PURIFICATION OF BACTERIOPHAGE.

1. A method for isolating a nucleoprotein from lysed staphylococci culture is described. 2.

ANAPHYLACTIC SHOCK BY AZODYES. II.

From the experiments presented, it follows that the specific precipitation and the production of anaphylactic shock with certain azodyes, as described previously, is due to these substances themselves and is not dependent upon formation of azoproteins by interaction of the dyes with proteins in the test tube or the animal body. Besides these, some other azodyes which in our tests did not give precipitation with corresponding immune sera were also found, in very small quantities, to induce anaphylactic contraction of the uterus of sensitized guinea pigs.

TWO SEROLOGICAL TYPES OF GROUP B HEMOLYTIC STREPTOCOCCI WITH RELATED, BUT NOT IDENTICAL, TYPE-SPECIFIC SUBSTANCES.

1. Among group B hemolytic streptococci one serological type previously described as homogeneous has been shown, instead, to contain two closely related types, distinguishable by reciprocal absorption experiments. These streptococci are designated Types Ia and Ib.