IN VITRO PRODUCTION OF NEW TYPES OF HEMOPHILUS INFLUENZAELeidy, Grace; Hahn, Eros; Alexander, Hattie E.
doi: 10.1084/jem.97.4.467pmid: 13052813
Two new types of Hemophilus influenzae, Sab and Sad have been produced in vitro . Each exhibits the presence of the type specific polysaccharides of 2 types of E. influenzae within the same cell. In Sab the polysaccharides of types a and b have been demonstrated and in Sad those which characterize types a and d. The Sab and Sad traits are inherited. Sab was produced by the action of DNA-containing extract isolated from type a on either type b cells or Rb cells (non-encapsulated non-type-specific cells derived from type b). Sad cells were formed as a result of the action of the DNA-containing extract isolated from type d on cells intermediate between Rab and Sab cells. DNA-containing extracts isolated from Sab cells have induced the Sab trait in Rd cells with predictable regularity. Evidence has been presented that the hereditary determinant of Sab cells is a new genetic substance with new functions. Therefore, the interaction of the DNA-containing substance from cells of one genetic type with living cells of a genetically different type has produced what appears to be a new individual which differs from each of the cells contributing the differing genetic traits but has at least one trait in common with each. Sab cells derived presumably from a single cell show the appearance of type b cells sometime during the first 7 generations. Footnotes Submitted: 19 September 1952
OSMOTIC HOMEOSTASIS MAINTAINED BY MAMMALIAN LIVER, KIDNEY, AND OTHER TISSUESOpie, Eugene L.; Rothbard, Mary B.
doi: 10.1084/jem.97.4.483pmid: 13052814
Osmotic pressure maintained by liver or kidney tissue measured by its water equilibrium with solutions of sodium chloride remains unchanged from 5 minutes up to 1½ hours following removal of the tissue from the body. Then with autolytic increase of molecular concentration within the cytoplasm of cells it reaches a higher level. Osmotic pressure maintained by pancreas or submaxillary gland, as ascertained in the same way, remains unchanged during ½ hour and later increases. Liver tissue of rat, mouse, guinea pig, rabbit, and cat maintains an osmotic pressure greater than twice that of the blood, and kidney tissue maintains an osmotic pressure somewhat less than twice that of blood. Fasting throughout a period of 7 days has little influence upon osmotic pressure maintained by cells of liver or kidney. Low protein diet has been found to depress osmotic pressure of liver cells after about 4 weeks, and with degenerative changes in the parenchyma, notably fatty infiltration, this pressure has remained at a diminished level during approximately 90 days. Increase of pressure within the common bile duct and the changes following biliary obstruction are accompanied by depression of the osmotic pressure maintained by liver tissue and ligation of the ureter diminishes the osmotic pressure maintained by kidney tissue. In both instances osmotic pressure tends later to rise to its former level. The osmotic pressure maintained by liver or by kidney tissue preserves an approximately uniform level under normal conditions and may be little changed by conspicuous injury to the organ. When this osmotic homeostasis is impaired by severe injury the pressure maintained by the tissue returns to its former level with recovery from the injury. Footnotes Submitted: 23 November 1952
WATER EXCHANGE OF COLLAGENOUS TISSUES AND OF GELATINOpie, Eugene L.; Rothbard, Mary B.
doi: 10.1084/jem.97.4.499pmid: 13052815
Water exchange of parenchymatous tissue, namely liver, kidney, or pancreas, occurs by osmosis, and the movement of water, as is well known, occurs in direct relation to the concentration of the surrounding solution. But the present work shows that the hydration of collagenous tissues, like that of gelatin, occurs in strong as well as in weak solutions of sodium chloride. The water intake of collagenous tissue in solutions of sodium chloride or of sucrose increases with increased density of the tissue and the sequence of changes is like that observed with gels of increasing gelatin content under the same conditions. Dense collagenous tissue, apparently impervious to the movement of water, exhibits a conspicuous ability to attract and hold it. Footnotes Submitted: 23 November 1952
THE EFFECT OF TEMPERATURE ON THE GROWTH OF VIRUS-INDUCED FROG CARCINOMALucké, Balduin; Berwick, Leonard; Nowell, Peter
doi: 10.1084/jem.97.4.505pmid: 13052816
The temperature coefficient of van't Hoff, Q 10 , for growth of frog carcinoma in vitro over a range of 20–35°C, averages 2.5. This value is closely similar to those obtained for various forms of normal growth. The values of the temperature coefficient slightly but progressively decrease with advancing age of the cancer colonies. A similar relation obtains in many but not in all forms of normal growth. Thus, the law of van't Hoff is found to hold equally for growth of the malignant tissue now under discussion and for normal tissue. Footnotes Submitted: 9 December 1952
OBSERVATIONS CONCERNING THE PRODUCTION AND EXCRETION OF CHOLESTEROL IN MAMMALSByers, Sanford O.; Friedman, Meyer; Biggs, Max W.; Gunning, Barbara
doi: 10.1084/jem.97.4.511pmid: 13052817
Accumulation of cholate in plasma is the immediate cause of hypercholesteremia in the rat with bile duct ligation and in the normal rat given intravenous sodium cholate. The hypercholesteremia induced by cholate administration does not appear to be dependent upon any preceding change in the rates of absorption, excretion, synthesis, or redistribution of cholesterol in the tissues of the animal. Cholate administration seems to induce hypercholesteremia by impeding the normal rate of passage of cholesterol from the plasma into the liver; this impedance is probably due to an alteration of the cholesterol-binding power of plasma proteins induced by cholate. The chemical and physiological implications of this finding are discussed. Footnotes Submitted: 18 November 1952
THE INACTIVATION OF COMPLEMENT AND ITS COMPONENTS BY PLASMINPillemer, Louis; Ratnoff, Oscar D.; Blum, Livia; Lepow, I. H.
doi: 10.1084/jem.97.4.573pmid: 13052820
Human complement is inactivated by plasmin, the proteolytic enzyme of plasma or serum active at or near neutrality. The addition of streptokinase to human serum, which converts plasminogen to plasmin, also causes the inactivation of complement components C'2 and C'4 and varying amounts of C'1. C'3 is the most resistant to inactivation by plasmin. Chloroform-activated human plasmin and bovine plasmin also destroy these components of complement, but are less effective than the streptokinase-activated enzyme. The inactivation of complement by the addition of streptokinase to human serum is inhibited by high hydrogen ion concentrations, low temperature, and elevated ionic strength. The inactivation of the components of complement in various fractions of serum is influenced by the available plasminogen and the content of plasmin inhibitors in these fractions. Certain similarities are pointed out between the components of complement and the factors in the plasmin system and between the inactivation of the components of complement by antigen-antibody reactions, by specific agents, and by plasmin. The possible significance of these relationships in immune hemolysis and complement fixation, and the possible role of the plasmin system in the instability of complement and the development of anticomplementary properties in serum are discussed. Footnotes Submitted: 8 December 1952