37 research outputs found

    GENERAL LEUCOCYTIC RESPONSE OF THE GUINEA PIG DURING THE REACTION OF ARTIFICIAL IMMUNITY IN EXPERIMENTAL TUBERCULOUS INFECTION

    Get PDF
    Guinea pigs have been rendered relatively immune against infection with virulent tubercle bacilli by preliminary inoculation with a suitable quantity of avirulent tubercle bacilli. Blood counts on these animals show that associated with the immune reaction there is a definite general leucocytic response characterized by an absolute increase in the total count, with an absolute and relative increase in the lymphocytes. The period of greatest activity coincides with that known to be the period of greatest reaction, based on anatomical evidence during the course of infection following this method of immunization. Moreover, blood counts made on animals inoculated with avirulent tubercle bacilli alone show an increase in the circulating lymphocytes during the period of greatest reaction to the infection, while blood counts on guinea pigs inoculated with virulent bacilli alone show an erratic course in which the polymorphonuclear forms are much increased, though not regularly so. These results indicate a parallelism between lymphoid activity and resistance of the animals to tuberculous infection, and suggest an association of lymphocytes with the factors determining this resistance, a relation which warrants consideration of the blood picture in the clinical study of tuberculous infection

    THE INFLUENCE OF X-RAYS ON THE PROPERTIES OF BLOOD

    Get PDF
    When rabbits are exposed to x-radiation as described, there results a definite change in the See PDF for Equation ratio of their plasma. This change is evidently one which defines a state of uncompensated alkali excess. The time required for a maximum change in the chemical reaction is the same as that required for a maximum change in the decrease of leucocytes. Sodium bicarbonate injected into the peritoneal cavity is followed by results identical with those observed following exposure to x-rays. The maximum changes occur in a shorter time following bicarbonate injection, but the relation between chemical and morphological changes are the same. We consider this analogy to be an important one in that it is suggestive of a relationship between the effect of salt and the effect of x-rays

    THE EFFECT OF RADIOACTIVE RADIATIONS AND X-RAYS ON ENZYMES : III. A UNIT OF MEASURE OF ACTIVITY FOR RADIUM EMANATION.

    Get PDF
    In this communication we have introduced a unit to express activity or power of a given preparation of radium emanation. We have named this unit the curie-power and defined it as the activity of 1 curie of radium emanation and its radioactive products in equilibrium with it. We suggest the introduction of this unit in order that we may make a more comprehensive statement of our experimental observation. In the radiochemical reaction effected by the radiations (beta and gamma) from radium emanation in which enzymes are inactivated the chemical change in a given system is a function of the product of two variables; namely, the average activity of the radium emanation, Pa, expressed in terms of the unit millicurie-power, and time, t, expressed in hours. This product has the dimensions of energy and is identical with W which is measured in terms of the energy unit, millicurie-power hours

    A METHOD FOR THE QUANTITATIVE DETERMINATION OF TRYPSIN AND PEPSIN

    Get PDF
    A quantitative method is described which permits a determination of the relative amount of trypsin or pepsin present in a gelatin-enzyme digestion mixture, provided the gelatin and trypsin solutions are purified. This method is dependent upon the change in viscosity of such solutions. It is found that the time required to cause a given percentage change in the viscosity is nearly inversely proportional to the amount of enzyme present. It is pointed out that the particular value of the method lies in the fact that enzyme reactions which take place in the presence of "buffer" salts may be studied

    THE EFFECT OF RADIOACTIVE RADIATIONS AND X-RAYS ON ENZYMES : VI. THE INFLUENCE OF VARIATION OF TEMPERATURE UPON THE RATE OF RADIOCHEMICAL INACTIVATION OF SOLUTIONS OF PEPSIN BY BETA RADIATION.

    Get PDF
    Data are presented which indicate that variation in temperature is associated with only slight variation in the speed of the radiochemical inactivation of pepsin in dilute solution

    A STUDY OF THE EQUILIBRIUM BETWEEN THE SO CALLED "ANTITRYPSIN" OF THE BLOOD AND TRYPSIN

    Get PDF
    1. The retarding effect of plasma on the action of trypsin can be measured quantitatively. 2. The nature of the reaction involved in effecting the retardation has been subjected to an experimental study. 3. Evidence is presented which indicates that the equilibrium between the inhibitive agent and trypsin is reached practically instantaneously and is rapidly and completely reversible. 4. This equilibrium has been studied by experiments in which we have observed (1) the effect of adding increasing amounts of plasma to a constant amount of trypsin, (2) the effect of varying the amount of trypsin while the plasma was constant, (3) the effect of dilution on the trypsin-plasma mixture. 5. The results of these experiments are discussed and it is stated that they are in quantitative agreement with the law of mass action. 6. An equation was found which fits the curves for the experiments mentioned in (4). This equation was developed from the assumption that 1 molecule of trypsin combined with 1 molecule of inhibitor to form 1 molecule of trypsin-inhibitor compound. The agreement between the results calculated by this equation and the observed results is satisfactory. It is pointed out that the equation contains two arbitrary constants and the bearing this fact may have on the calculated results is discussed. 7. We conclude from the results of our study that we have adduced evidence which suggests the following statement regarding the so called "antitryptic" property of blood. The inhibitive agent and trypsin combine to form an inactive but dissociable compound. The reaction in equilibrium is expressed by the equation Trypsin + inhibitor β‡Œ trypsin-inhibitor The conditions of equilibrium are apparently governed by the law of mass action. The behavior of the equilibrium is therefore similar to the behavior of other equilibria between different inhibitive agents and enzymes discussed in the paper

    THE EFFECT OF RADIOACTIVE RADIATIONS AND X-RAYS ON ENZYMES : IV. THE EFFECT OF RADIATIONS FROM RADIUM EMANATION ON SOLUTIONS OF INVERTASE.

    Get PDF
    The radiochemical inactivation of invertase by beta radiation from the radioactive products in equilibrium with radium emanation can be explained quantitatively on the same basis as that of trypsin and pepsin previously reported; namely, the rate of change in the logarithm of the concentration of the active enzyme with respect to the variable, W, is constant, under the conditions of irradiation described, when the volume of solution exposed is constant. When, within the limits stated in this paper, this volume (V) is varied, the rate of radiochemical change is inversely proportional to V; i.e., See PDF for Equatio

    THE EFFECT OF RADIATIONS FROM A MERCURY ARC IN QUARTZ ON ENZYMES : I. THE EFFECT OF ULTRA-VIOLET RADIATION ON PEPSIN IN SOLUTION.

    Get PDF
    Pepsin in solution is inactivated by the radiations from a mercury arc in quartz. It would seem that the effective radiations are those in the ultra-violet region of the spectrum. The form of the curve describing the course of the inactivation is the same as that found for monomolecular chemical change

    THE EFFECT OF RADIOACTIVE RADIATIONS AND X-RAYS ON ENZYMES : II. THE EFFECT OF RADIATIONS FROM RADIUM EMANATION ON PEPSIN IN SOLUTION.

    Get PDF
    Pepsin in solution is inactivated by the radiations (beta and gamma) from radium emanation. This chemical effect has been studied quantitatively. The principles involved in this radiochemical reaction are apparently the same as those found in the case of trypsin previously reported; namely, the change in the logarithm of the concentration of active enzyme varies directly with the variable, W

    THE EFFECT OF RADIOACTIVE RADIATIONS AND X-RAYS ON ENZYMES : V. THE INFLUENCE OF VARIATION OF THE THICKNESS OF THE ABSORBING LAYER OF SOLUTIONS OF PEPSIN UPON THE RATE OF RADIOCHEMICAL INACTIVATION OF THE ENZYME.

    Get PDF
    Evidence is presented which indicates: (1) that the effect of gamma radiation is negligible with respect to that of beta radiation upon pepsin in dilute solution under the conditions employed in the experiments made; (2) approximately the thickness of fluid layer which may be regarded as necessary and sufficient to practically completely absorb the available beta radiation; (3) that the mean reaction speed coefficient in radiochemical inactivation of pepsin varies inversely with the volume of solution irradiated if the thickness of the fluid layer satisfies the sufficient condition stated in (2), and beyond this as far as has been studied
    corecore