H. S. Mayerson

Studies in Acetylphenylhydrazine Anemia in Dogs.

Anemia was produced in 5 adult dogs by subcutaneous injection of acetylphenylhydrazine (pyrodin). The amounts injected were calculated in terms of red cell volume as determined from hematocrit and plasma volume readings and varied from 40 mg. to 100 mg. per 100 cc. of red cells, given in single or divided doses. The dogs were fed a standard diet in order to minimize possible dietary effects. Some degree of anemia, coincident with an increase in the icteric index, was present in all cases at the end of 24 hours. The anemia becomes most marked in 5 to 9 days after the first injection, the red cell and Hb determinations at this time showing values of from 33 to 67% of the original levels. Single injections produce a similar degree but a more rapid onset of the anemia than do divided doses of the same amount. The disappearance of the anemia is gradual, recovery beginning 12 to 16 days after the first injection. Approximately normal levels are reached in 3 to 5 weeks after injection. The percentage of reticulocytes increases to approximately double the normal values in 2 or 3 days after the pyrodin is injected and usually remains at this level. The first indication of recovery from the anemia is usually preceded by a further, sudden marked rise, the value reaching 33% in one experiment. The corpuscular volume shows a tendency to increase and to remain high even after the anemia has disappeared. The same is true of the resistance of the red cells which increases gradually and is greatest at the height of the anemia. The behavior of the white cells is irregular. The total is increased from 50 to 100% at the height of the anemia.

The effects of radiation on calcium and phosphorus.

As a part of a problem on the effects of darkness and of radiation on the metabolism of normal dogs, we followed the balances and blood levels of calcium and phosphorus before and after radiation with a 25 ampere flaming arc, with a spectral energy distribution of approximately 50 per cent ultra violet, 11 per cent visible, and 39 per cent infra red. The animals were fed on a standard maintenance diet furnishing 70 calories per kilo body weight, and well balanced and complete in calcium and phosphorus. All the animals were on positive balances at the beginning of the experiments. Under normal laboratory conditions there is a balance between the two constituents, a slight rise in serum phosphorus being accompanied by a similar decrease in the serum calcium, and vice versa. Radiation of one hour at 40 cms. (total energy equivalent to 55.44 gm. cal. per cm.2) for 8 days served to accentuate this balance, there being a marked increase in the phosphorus and a corresponding decrease in the calcium during the radiation, and a return to normal soon after the radiation was stopped. On repeated exposures of the same duration, however, both constituents show almost parallel curves, a rise in phosphorus being accompanied by a simultaneous increase in calcium. Single doses of two hours for 8 days on other dogs gave results similar to those obtained on repeated exposures. Grant and Gates 1 have reported similar findings in the rabbit. Examination of the urine and feces shows that, although in some cases the actual amount of excretion is not markedly increased, the percentage found in the urine relative to the feces is always larger, indicating an increased absorption and retention of these constituents in the blood.

SUMMARY OF THE INTENSITY AND SPECTRAL DISTRIBUTION OF SOLAR RADIATION AT NEW ORLEANS 1931–40, INCLUSIVE

this period except that in September 1939 the Richard recording millivoltmeter used in conjunction with the Eppley pyrheliometer for the continuous measurement of total radiation on a horizontal plane was replaced by a Leeds and Northrup recording potentiometer. For the most part, measurements of solar radiation at normal incidence and its spectral distribution-ultra-violet, luminous and infra-red-were made at 10 a. m., 12 in. and 2 p. m. on days when the sun was unobscured by clouds or haze. Measurements were also made at the same times of the spectral distribution of the total radiation, direct and diffuse, and of the diffuse sky radiation only, as received on a horizontal surface. Spectrograms to show the short-wave-length limit of the spectrum were also taken at these times. The determinations for 1931 were made from a tower about 40 feet above sea level built on the roof of a small building adjacent to the lakorato ;

Seasonal Variation in Efficiency of New Orleans Sunshine and Skyshine in Promoting Growth and Preventing Leg Weakness in Chicks.

Groups of 2-week-old chicks, fed a leg weakness-producing diet, were exposed daily for 6 weeks to different amounts of sunshine and skyshine between 10:00 A. M. and 1:00 P. M. Growth was followed by weekly weighings. As judged by appearance, attitude, roentgenograms and blood calcium and phosphorus, an average daily exposure to sunshine of 4 to 5 minutes from October, 1929, through March, 1930, and of 2 to 3 minutes through April, 1930, prevented leg weakness. An average daily exposure to skyshine of 62 minutes protected the chicks from October, 1929, to the middle of February, 1930, 28 minutes sufficed from that time through March, 1930, and 23 minutes during April, 1930. We are confident that smaller amounts of radiation would have been effective. Better growth was obtained in the skyshine than in the sunshine animals from October 16 to January 10, indicating that the exposures to direct sunshine were, perhaps, too long.

The Measurement and Specification of Radiant Energy

NO one who uses radiant energy, solar or artificial, for therapeutic or experimental purposes will question the necessity of measuring and specifying it. Personally we feel that the specifications should be in absolute units, the erg or the calorie, and since the methods permitting this are no more difficult than those giving results expressible only in arbitrary units, there is no valid reason why such methods should not be used universally. The radiations from artificial sources admittedly represent but approximations to sunlight, and no two sources are alike in respect to the spectral distribution of the energy they emit. This is the physical reason why different sources can not produce the same therapeutic or biological action. We are not so much interested in making comparisons between the energy emitted by different sources, and their biological or therapeutic action, as in knowing that the energy is different and that we do not speak of the energy emitted by this, that, or the other lamp as represe...

Ineffectiveness of Radiant Energy on Hemorrhagic Anemia in Dogs.

Twenty white animals in which the Hb level had been reduced by 3 or 4 successive hemorrhages, at from 2 to 3 days intervals to between 35 and 50%, were fed the standard Whipple (salmon bread) diet and irradiated with the flaming C (“Pan Ray”) arc. The interval between successive exposures, as well as their number and intensity, was varied in different experiments and in successive periods of the same experiment. The efficacy of the experimental procedure in effecting regeneration was measured by the amount of Hb which had to be removed during the experimental period, as compared with that removed during earlier and later control periods, in order to keep the Hb at the chosen reduced level. Such irradiation produces a marked increase in the number of erythrocytes which progressively decrease in size but maintain a normal saturation, as was earlier reported for “normal” animals. The eventual decrease in red cell number during the later part of the post-irradiation period is accompanied by a reciprocal increase in the size. A pronounced increase in the percentage of reticulocytes usually precedes that of the total red count. In 5 experiments the reticulocyte percentage is double, or more than double, that preceding irradiation. Massive exposures (75 to 133 g. cal. per sq. cm.) given at long intervals are usually more effective than are smaller doses repeated more often. An increase in Hb was noted in only one experiment. In 11 cases the amount of Hb formed during and immediately following the irradiation period was less than in previous or later control periods. In the remaining 8 cases there was no effect. It is to be emphasized that dried peaches, apricots, or lettuce added to the diet of animals which had shown no response to radiation produce their typical influence, although the accelerated Hb regeneration produced by adding these substances to the standard diet was not demonstrably influenced by any dosage of radiant energy.

The Effect of Carbon Arc Radiation on Circulation in the Dog.

Depression of the general arterial blood pressure by radiant energy has been repeatedly demonstrated, although a rise in pressure, during or soon after irradiation, has also been recorded. We have investigated the effects of known amounts of carbon arc radiation on the blood pressure, pulse rate and body temperature of normal adult dogs under standard conditions. A total of 13 experiments on 8 dogs have been completed, 11 with the Majestic Arc, and two with the Pan Ray Arc∗ as the source of energy. The distribution of the energy irradiated by the two lamps, as determined spectroradiometrically† is approximately, for the Majestic Lamp or “Solarite”: ultra-violet 21.9 p. c., visible 43.5 p. c., infra red 34.6 p. c., and for the Pan Ray Arc 15, 59 and 26 per cent, respectively. The total energy of the “Pan Ray Arc” is about 6 times that of the Majestic, being equal to 1 gm. cal. per sq. cm. per minute at 103 cm. In the experiments with the Majestic Arc the animals were irradiated daily for 1 hour, either on the back or the abdomen, at a distance of 40 cm. from the lamp for periods of from 8 to 33 days. Each dose had a total energy equivalent to 55.44 gm. cal. per sq. cm. In 2 experiments the time of the exposures was increased to 2 hours daily for 8 days. In the first experinaent with the Pan Ray Arc, the abdomen of the animal was irradiated for 45 minutes at 1 meter (45.0 gm. cal. per q. cm.) and the dosage progressively increased during a period of 13 daily exposures. In the second experiment, the animal was exposed to massive abdominal exposures at intervals of 2 or more days.

The effect of light and of darkness on some urinary and blood constituents in the dog.

As a part of the general problem of the influence of light on “normal” animals, a study is being made of changes induced in dogs subjected to longer or shorter successive periods of darkness and of light. At the present time we desire to report a series of results on certain chemical constituents of blood and urine. Two female dogs, M and G, were brought into the laboratory on November 10, 1923, and placed in large metabolism cages. Dog M was a full grown adult weighing 17.2 Kg., while dog G was about a year old, weighing 12.8 Kg. The room in which the cages were kept was well ventilated and lighted, having a southeastern exposure. Temperature was read on a maximum and minimum thermometer, and registered a maximum variation of 4°C.; while wet and dry bulb readings showed the humidity to be constant. The diet used was that recommended by Cowgill 1 supplemented by 40 mg. per kilo of Harris yeast vitamine powder made into special tablets containing 50 mg. vitamin extract and 50 mg. inert starch. The diet (see Table I) furnished 80 calories per kilo body weight, and has been shown to be ample for the maintenance of dogs under ordinary laboratory conditions. The dogs were allowed to become accustomed to the food and surroundings, until analyses of urine and blood indicated nitrogen balance. Catheterization was done daily with due precautions against infection. Usually the urine was analyzed immediately. When this was impossiblle the sample was covered with toluene and kept in the refrigerator. The cages were cleaned daily to prevent contamination of the urine by hair and feces. When desired for analysis, blood was drawn from the femoral artery under oil, immediately after catheterization.