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Intravenously administered Triton WR-1339, a nonionic surface active agent, has been used as an endogenous hyperlipemic agent since 1951. We expected Triton to increase food consumption to supply, at least partially, the energy and acetyl groups necessary for producing the hyperlipemic state. In this study, however, we observed that the rats injected intravenously with various dose levels of Triton decreased their voluntary food intake in a dose-related manner. Two other nonionic surface active agents, Tween 20 and Tween 80, given intravenously did not alter food intake. Further studies revealed that Triton WR-1339 administered intravenously 30 min before feeding by stomach tube resulted in a marked delay in the rate of gastric emptying which was also dose related. A delay in gastric emptying has previously been suggested as one mechanism that controls food intake. Tween 20 and Tween 80 did not alter the rate of gastric emptying. We suggest that the mechanism responsible for the decrease in voluntary food consumption in Triton WR-1339 injected rats may be due to the delay of gastric emptying in these animals.

Recent attempts to isolate the active agent of the Rous chicken sarcoma have resulted in conflicting views as to the nature of the causative agent. Jobling and Sproul1-2 have reported that repeated injections of a lipid fraction obtained from fresh or dried tumor tissue, together with nonspecific protein, produce sarcomas which appear in the more responsive birds within 3 to 4 months after the third injection. Fraenkel and Mawson,3 on the other hand, were unable to obtain tumors by injecting acetone extracts of fresh or dried tumor tissue but were successful with the residue.In 1936 we attempted to isolate lipid fractions from a very active preparation of Rous chicken tumor No. 1 with pentane and chloroform as solvents. With neither were we successful in producing tumors in young birds. The residue of the pentane extract, however, invariably produced tumors after a single injection in spite of 4 extractions of the powder with 100 volumes of solvent (see Table I). The residue from the chloroform extract wa...

SummaryScopolamine in small doses (0.3-0.4 mg) given intranasally by spray 30 minutes prior to exposure, exerted significant protection against swing sickness. During actual flight testing, addition of a surface active agent (sodium lauryl sulfate-Duponal C) increased its effectiveness. Nasal instillation to subjects 15-20 minutes after take-off sharply reduced the incidence of vomiting from airsickness during subsequent 40-45 minutes. Oral and sublingual administration under these conditions were ineffective. Considerable variations in the drug instilled resulted when given by spray. The use of nose drops allowed more accurate medication. The significance of this mode of administration for treating motion sickness is discussed.

SummaryFrom the nature of the function relating the effectiveness of sulfonamides to the hydrogen ion concentration the conclusion can be drawn that the active agent in a sulfonamide solution is an anionic species.

In a previous communication1 we reported that the active agent in the Rous chicken sarcoma filtrate could be concentrated and partially purified by adjusting the filtrate, normally about pH 7.2, to a reaction of pH 4. When brought to this reaction with a phthalate buffer, the tumor-producing agent is carried down with the precipitated portion. When this precipitate is extracted at pH 8, the carcinogenic agent is not only set free, but the activity of the extract seems definitely greater than that of the original filtrate.To account for the increased activity of the first extract at pH 8, several possibilities suggested themselves; among others, that the active agent in the filtrate may be in combination with substances that restrain its activity to some extent, and that in the process of precipitation by the method described above, there is brought about dissociation between the restraining or protective agent and the tumor-producing element. If true, this would explain why the extract of the first precip...

In testing the therapeutic value of the lysed cultures of B. diphtherias it became necessary to destroy the slight amount of toxin present with bacteriophage in some of the filtrates. Since bacteriophage is comparatively resistant to heat it was thought that simple exposure to heat may destroy the toxin without destroying the phage present in the lysates. This, however, we were not able to accomplish. Exposure to heat sufficient to destroy all the toxin caused almost complete destruction of the phage. In a study of the mechanism of inactivation of phages by alcohol we concluded that the effect of alcohol was not due to the direct destruction of the active agent, but to the denaturation of the protein vehicle on which the lytic agent was adsorbed.1 Suspecting that somewhat similar relation may exist in the inactivation of phages by heat, we attempted 2 series of experiments.In the first we made use of our earlier finding that the addition of polyvalent cations to the medium containing phage protected it fr...

conclusionAtoxyl is probably transformed into a trypanocidal substance in the living body both by the blood and by the liver (other organs were not tested). In tests in vitro the transforming agent in liver may be readily distinguished from the active agent in blood.

We have previously described1 the presence of a tumor inhibiting substance in the filtrate of the Rous chicken sarcoma and in normal chicken sera. It was found that this inhibiting substance is retained in the supernatant fluid when the tumor filtrate is brought to pH 4, while the active agent is carried down in the precipitate. In a more recent report, Murphy2 and his associates report results that would seem to confirm these observations.The fact that the activity of the agent can be inhibited by the supernatant fluid and sera made it of interest to ascertain whether the agent was actually destroyed in such mixtures or whether its tumor producing properties were merely inactivated. In order to answer this question it became necessary to determine if it is possible to recover the agent in an active state from these non-infective mixtures. The supernatant fluid used was prepared by adding an equal amount of a phthalate buffer solution at pH 4 to a 20% filtrate of the Rous chicken sarcoma. After standing f...

Susceptibility and resistance to a particular line of inoculable mouse leukemia may, for present purposes, be defined in terms of the presence or absence of conditions necessary for the survival of the active agent. A group of 11 such lines of agent, each of which originated in a different case of spontaneous lymphatic leukemia in a highly inbred strain of mice designated as C58, found the necessary conditions for survival in mice of the same strain.1 Although different lines of agent can grow in the same pure bred strain of mice, these different lines do not all have the same requirements for survival, as has been shown by hybridization experiments.2 The present report gives direct evidence of the specificity of requirements of different lines of agent, without the use of hybridization, by means of a new line that originated from a spontaneous case in another highly inbred strain of mice.The new line of agent is designated line L. The spontaneous case that gave rise to this line was a mouse in strain 89;...

All existing evidence seems to indicate that the active agent responsible for transmissible lysis of bacteria is distributed in the medium as if it were particulate.1 Several authors are inclined to consider these particles as autonomous units of an organized protoplasm.In this connection it is of interest to measure and in other ways to identify these particles as such. Several attempts have been made to measure them. In most instances, these particles were2, 3, 4, 5 forced through membranes of presumably known porosity. Because of the limited value of this method, von Angerer6 tried to arrive at more reliable figures by the nephelometric method, and Bechold7 used an ingenious gold cast method. While the figures obtained by these various procedures are not identical, they are sufficiently close to indicate, at least, that in all cases authors were dealing with particles of approximately the same order of magnitude.A recent paper of Northrop and Anson8 offers means to inquire into this question by the use...

A simple method1, 2 for the cultivation of vaccine virus was described which consisted of minced viable chick embryo tissue suspended either in Tyrode's solution or in a mixture of Tyrode's solution and rabbit serum. Recently it has been shown that the viruses of vesicular stomatitis3 and poliomyelitis4 are capable of multiplication in media similar to that used for vaccine virus. For the cultivation of the former active agent, minced chick embryo tissue suspended in Tyrode's solution was used, while for the latter minced chick embryo brain tissue suspended in a mixture of monkey serum (1 part) and Tyrode's solution (9 parts) was employed. During the past year we have been investigating louping ill, a neurotropic virus disease of sheep which in some respects resembles poliomyelitis. After the appearance of Gildemeister's note4 on the cultivation of poliomyelitic virus, it seemed of interest to determine whether another neurotropic virus, the etiological agent of louping ill, is capable of growth in vitro ...

SummaryThe West Nile virus multiplies rapidly throughout the embryonated egg following inoculation by any of the usual routes. The embryo contains large amounts of virus while the allantoic fluid contains comparatively small amounts of the active agent. Death of the infected embryos occurs with such regularity that titration of virus can be made as well in eggs as in mice.