Paul A. Zahl

Induction of Decidua-Placental Hemorrhage in Mice by the Endotoxins of Certain Gram-Negative Bacteria

Summary Endotoxin-containing extracts of Shigella paradysenterie Flexner, Salmonella typhimurium, and Rhodospirillum rubrum when injected intraperitoneally into mice pregnant from 12 to 18 days induce decidua-placental hemorrhage which results either in abortion or resorption of the embryos. It is pointed out that such decidua-placental hemorrhage induced by the endo-toxins of gram-negative bacteria may fall into the same class of physiological action as hemorrhage induced in implanted tumors following administration of endotoxins of gram-negative bacteria.

Localization of Colloidal Dyes in Animal Tumors

Summary (1) As earlier workers have shown, acid dyes do not localize in tumor cells but in the stroma surrounding the tumor. (2) Further localization takes place within the tumor at each interface of viable and necrotic tissue. (3) The initial localization consists of a diffuse staining of the peripheral stroma and the seminecrotic cells within the tumor between viable and necrotic zones. (4) This diffuse dye is progressively phagocytized, and after 24-48 hours, appears in numerous macrophages at the tumor edge. (5) The dye is so located that if it were replaced by a radioactive substance, theoretically effective radiation of the tumor edge should result. (6) After a single large dose of dye the reticulo-endothelial cells of liver and spleen are rapidly filled with dye droplets. These disappear or diminish substantially after several days. (7) In addition to tumor and reticulo-endothelial systems of liver and spleen, the kidneys take up considerable quantities of dye, as this is the chief channel of excretion. Accumulation in the kidney might prove to be a complicating factor in the use of radioactive materials, but in the case of induced activity, as with lithium by slow neutrons, appropriate shielding during irradiation should overcome this difficulty. (8) Small repeated doses of dye do not localize in greater quantities than does the same amount given at a single injection. Furthermore, the reticulo-endothelial system is blocked by small repeated doses. (9) X-ray treatment does not appreciably alter the amount of dye localizing in tumors, as determined by histological examination. (10) There is a marked difference in behavior, as regards tumor localization, between the colloidal dyes used and colloidal carbon. (11) Brief preliminary report is made on the localizing properties of some heretofore untested dyes.

Age as a Factor in Susceptibility of Mice to the Endotoxin of Bacillary Dysentery.

Summary Dose-survival curves obtained by injecting the endotoxin of Shigella paradysenteriæ Flexner into 12-, 20-, and 35-g mice indicate that such mice are killed by approximately the same minimal amounts of toxin, and that this effect is not considerably modified within the limits of age or normal weight indicated. This effect is interpreted as injury to a single system, most probably the vascular system.

Cytological Changes in Frog Pituitary Considered in Reference to Sexual Periodicity

Recent experiments with Amphibia indicate that the anterior lobe of the pituitary exerts a controlling influence not only on the development of the primary sex organs, but also on the release and discharge of the sex products. Wolf 1 and Rugh, 2 working with various Anura, have demonstrated that amplexus and shedding of the sex products can be induced in mid-winter by simple hetero- or homoplastic implantation of anterior lobe tissue. Houssay and Lascano-Gonzales 3 observed a degeneration of the testes following hypophysectomy in the toad. The writer wishes to present briefly the results of a cytological study of the frog anterior lobe, and on the basis of cytological evidence to postulate the rôle played by the pituitary in the mechanism of sexual periodicity. Several species of the genus Rana were used in this study. At regular intervals throughout this annual cycle specimens were killed and the cytological condition of the anterior lobe pituitary was noted. Various sublimate and osmic acid fixatives were used in preparing the tissue for microscopic examination. Staining procedure most consistently used was a modification of the acid fuchsin-methyl green technique. The general pattern of the winter frog anterior lobe is similar to that found in the other vertebrates. The numerical proportion, the inclusions and the structure of the cell types, however, do not conform entirely to those of the higher vertebrates, particularly mammals. The basophiles are small cells, few in number, and their general appearance does not suggest high secretory activity. True acidophiles, on the other hand, are larger and are filled with densely packed acidophilic granules. True chromophobes are as large as the acidophiles, but are more or less free of specific granulation. Grading between the true acidophilic type and the true chromophobic type are found cells exhibiting intermediate stages of acidophilic granulation, some containing comparatively few acidophilic granules, while others approach the true acidophiles in amount of granulation present.

Effect of Sulfonamides on Toxic and Antigenic Actions of Endotoxins of Certain Gram-Negative Bacteria.

Summary Orally administered sulfanilamide, sulfathiazole, sulfapyridine, sulfadiazine, sulfamerazine, and sulfaguanidine confer an equivalent but limited protective effect against the lethal action of intraperi-toneally-administered endotoxin of Salmonella typhimurium. Sulfanilamide has a similar effect on the endotoxin of Shigella paradysenteriæ Flexner. Sulfathiazole administered during the immunization of mice with Salmonella endotoxin appears not to interfere with the immunizing process, as determined by degree of resistance to the lethal action of the endotoxin. Reasons are advanced to support the view that these results apply to other sulfonamide drugs and to the endotoxins of gram-negative bacteria generally.

Action of Bacterial Toxins on Tumors. IV. Distribution of Tumor-Hemorrhage Agents Among Bacterial Species.

Conclusions An extension was made of an earlier survey of bacterial substances inducing hemorrhage in implanted mouse tumors. It was found that with a few exceptions gram-negative forms induced tumor-hemorrhage, while this property, with one exception, was lacking in the gram-positives. An interesting example was the induction of hemorrhage by the photosynthetic gram-negative purple bacterium Rhodospirillum rubrum. It is concluded that toxins inducing tumor-hemorrhage, and probably bound up in the complex O antigens, are characteristic of gram-negative bacteria.

Action of Bacterial Toxins on Tumors. VI. Protection Against Tumor Hemorrhage Following Heterologous Immunization.

Summary Mice immunized with endotoxin preparations of Shigella paradysenteriœ Flexner, Salmonella typhimurium and Rhodospirillum rubrum were found to have been protected against the induction of hemorrhage in implanted tumors. Protection by immunization was found to be about as effective against the induction of tumor hemorrhage when the heterologous organisms were used as when the homologous were used. This finding supports our earlier hypothesis that a common antigenic toxic component is characteristic of gram-negative bacteria generally.

Action of Bacterial Toxins on Tumors. III. Some Biological Properties of Purified Salmonella typhimurium Endotoxin

Conclusion The acetone, phenol, and various formamide fractions in the extraction of Salmonella typhimurium endotoxin when tested on mice were active in respect to (1) lethality, (2) the induction of hemorrhage in implanted tumors, (3) the production of antibodies which protected mice against the toxic material.

Adenosine triphosphate levels in mouse blood after whole-body irradiation and during tumor growth.

Summary No changes were observed in the blood levels of total nucleotide or of adenylic acid, adenosine diphosphate, or adenosine triphosphate during the wasting period that follows whole—body X-ray irradiation of mice. Massive injected doses of ATP failed to induce overt symptoms of shock in mice. In mice bearing implanted tumors there is a continuous decrease in blood adenosine triphosphate until about the 10th post—implantation day, followed thereafter for several days by a slight but significant rise in the ATP curve. The first phase of this curve parallels, on the time scale, the increase in tumor weight. Mice whose tumors were extirpated at stated intervals after implantation show a tendency to return to the normal ATP blood level. There is no apparent relation between changes in ATP blood levels and body weight, cell—fluid ratio in the blood, or hemoglobin, at least up to the 10th post—implantation day. No significant changes were observed in the total nucleotide values for blood during tumor growth; nor was the adenylic acid or the adenosine diphosphate picture different from that of normal mice.

A Cross-Protective Reaction Between Moccasin Venom and the Endotoxin of Salmonella typhimurium.

Summary Mice immunized with moccasin venom were protected against otherwise lethal doses of the endotoxin of Salmonella typhimurium; and, inversely, salmonella-immunized mice were protected against the venom. This cross-protection may be due to the presence in gram-negative organisms and moccasin venom of a common factor characterized by hemorrhagic action, antigenicity, and a lack of serological specificity.