Margaret G. Smith

Propagation in tissue cultures of a cytopathogenic virus from human salivary gland virus (SGV) disease.

Conclusions A cytopathogenic virus inducing large intranuclear inclusions like those occurring in salivary gland virus disease has been isolated from the tissues of each of 2 infants. In both cases the virus has been propagated serially in cultures of human fibroblasts derived from uterine tissue. The distinctive cytopathogenic effects and the apparent species specificity of the 2 viruses, together with the isolation of each of the viruses from human tissue which contained the characteristic inclusions of salivary gland virus disease are substantial evidence that these viruses are strains of the human salivary gland virus.

Propagation of Salivary Gland Virus of the Mouse in Tissue Cultures.

Summary and Conclusions Cytologic changes including large intranuclear inclusions were produced in cultures of mouse tissue inoculated with salivary gland material from mice infected with the salivary gland virus. They also occurred in 2 serial subcultures. The large intranuclear inclusions resembled those occurring in cells of the mouse salivary gland. Further evidence that the mouse salivary gland virus has been propagated in serial passages in cultures derived from mouse embryonic tissue is as follows. After 3 serial passages of the infective agent in the cultures the salivary gland virus disease, as characterized by specific intranuclear inclusions, has been reproduced in the salivary glands of mice by intraperitoneal inoculation of the supernatant fluids from the cultures. Also the infective titers of supernatant fluids withdrawn from cultures at intervals have been determined by titrations in mice. The results of the titrations, together with the calculated dilutions of the original inocula effected during the course of the experiments, demonstrated significant increase in the virus in 3 serial passages in tissue culture.

Effect of Adrenalectomy on Spontaneous and Induced Proteinuria in the Rat.

Summary 1. Bilateral adrenalectomy abolishes or greatly reduces the types of experimentally produced proteinuria studied in the saline maintained rat. 2. The normal, spontaneous proteinuria of the male rat is significantly reduced by bilateral adrenalectomy. 3. Cortisone administration to bilaterally adrenalectomized male rats increases their spontaneous proteinuria to normal control levels. 4. Adrenal cortex extract, esoxycorticosterone acetate, and cortisone restore the ability of the salt-maintained, adrenalectomized rat to respond to renin injection with massive proteinuria.

Further Isolation of St. Louis Encephalitis Virus ; Congenital Transfer of Virus in Chicken Mites (Dermanyssus gallinae).

Summary The virus of St. Louis encephalitis has been isolated from chicken mites (Dermanyssus gallince) on 7 separate occasions from 3 of 5 sources in St. Louis County from which mites were collected. Two of these isolations from a single chicken house were reported in a previous publication. Since that time 3 further isolations have been accomplished from mites collected at this original site, and in addition one isolation has been made from each of 2 other chicken houses. All 3 sites are located in St. Louis County within a radius of 11 miles. Mites infected in nature have been shown to retain the virus after 5 months of propagation in the laboratory. Congenital transfer of the virus from the adult female through the egg into the first stage nymph has been demonstrated.

Is Ant. Pituitary Hormone Demonstrable in Urine of Graves Disease, in Urine of Guinea Pigs Injected With Ant. Pituitary Extract?

Loeb and Bassett 1 have shown that an acid extract of cattle anterior pituitary produces hypertrophy of the thyroid gland of guinea pigs. They noted that this experimentally produced hypertrophy characterized by an enlargement of the acinar cells, softening and absorption of colloid, and an irregular and often slit-like shape of the acini, and by the formation of papillary ingrowths into the acini resembles the pathological change in the thyroid gland in Graves disease. In a series of papers from this laboratory this similarity between the effects produced by the injection of extracts of the anterior pituitary gland of cattle and the symptoms of Graves disease has been further emphasized. Loeb and Friedman 2 have produced exophthalmos in guinea pigs by repeated intraperitoneal injections of acid extract of the anterior pituitary. Siebert 3 showed that this extract produced a rise in metabolism which was counteracted by the administration of potassium iodide, observations which accorded with the depressing effect of potassium iodide on the hypertrophy of the thyroid gland elicited by anterior pituitary which had previously been noted by Silberberg. 4 McCordock and Hageman 5 produced tachycardia in guinea pigs by means of this extract. Closs, Loeb, and MacKay 6 in joint investigations from this laboratory and the Scripps Metabolic Clinic in La Jolla, found the changes in the distribution of iodine in the thyroid gland and in the blood called forth by extract of anterior pituitary to be the same as those observed in Graves disease. Notwithstanding the similarity between these two conditions, Loeb 7 believes that while the anterior pituitary may possibly play a certain role in the etiology of Graves disease, there is reason for assuming that various other factors may elicit an overaction of the thyroid gland.

Placental Transmission of Immunity to St. Louis Encephalitis Virus Inoculated Intraperitoneally in Mice.

Conclusions Placental transmission of specific immunity to the virus of St. Louis encephalitis has been demonstrated. Mice between 7 and 9 days of age and 13 to 14 days of age born of mothers immunized by the subcutaneous inoculation of active virus show no increased resistance to the virus of St. Louis encephalitis inoculated intracerebrally but are more resistant than control mice of the same age to virus inoculated intraperitoneally.

Comparison of Activity of Viruses of St. Louis and Japanese Encephalitis in the Chick Embryo

Conclusion The Japanese encephalitis virus and the St. Louis encephalitis virus produce the same type of changes in the chorioallantoic membrane and in the brain of the chick embryo. The two viruses multiply in the egg to approximately the same titer as demonstrated by mouse inoculation. Whether these observations imply more than a similarity of action of the two viruses is not clear from data available from this study.

A Comparison of the Incubation Period of Poliomyelitis in Mice of Different Strains.

Conclusions It is concluded from these observations that, although strain differences are found, other factors than constitution are important in determining the variable incubation periods observed with the Lansing strain of poliomyelitis virus within strains oi white mice.

Serological Relationship between the Viruses of Japanese B and St. Louis Encephalitis.

Although many points of resemblance between the viruses of St. Louis and Japanese B encephalitis have been emphasized, the evidence supporting their serological relationship is conflicting. In neutralization tests in mice, Kawamura 1 and his associates found no cross protection with antisera prepared in mice, rabbits and goats by immunization with the viruses of Japanese and St. Louis encephalitis, nor with sera of patients convalescent of the two diseases. Kasahara 2 and his colleagues found that the Japanese hyperimmune serum of rabbits neutralized both the Japanese virus and the St. Louis virus, but the latter only to a slight degree. On the other hand, the St. Louis immune serum neutralized only the St. Louis virus. With one of the strains of St. Louis virus used, this slight cross protection was apparent when the virus-serum mixtures were instilled intranasally but not when inoculated intracerebrally. Kudo 3 and his collaborators observed that sera of rabbits immunized with the Japanese encephalitis virus neutralized not only the homologous virus, but to some extent the St. Louis virus. Their tables show that protection of mice against 1 to 100 minimal lethal intracerebral doses of the St. Louis virus was afforded by immune sera from each of 3 rabbits. In protection tests in mice, Webster 4 found no cross neutralization of the Japanese and St. Louis viruses with the sera of individuals convalescent from either Japanese B encephalitis or St. Louis encephalitis. However, he cites an instance of cross neutralization with human sera noted by Kuttner. 5 Sera obtained by Kuttner from two Europeans who had contracted encephalitis in China protected against both the Japanese and the St. Louis viruses. Furthermore, Webster 4 obtained no cross protection against the Japanese virus with the serum of a monkey hyperimrnunized with the St. Louis virus; but with serum from a monkey hyperimrnunized with the Japanese virus, mouse protection was afforded not only against the Japanese virus but against at least one minimal lethal dose of the St. Louis virus.

Effect of Prolonged Passage in the Chick Egg on the St. Louis Encephalitis Virus

Summary After 68 passages on the chorio-allantoic membrane of the chick there is no increased proliferation of the virus on the membrane. The virulence of this virus after cultivation in eggs for 9 months has been demonstrated to be the same for the mouse as that of the original inoculum of the eggs. The virus content of the chick embryo brain is consistently slightly greater than that of the corresponding chorio-allantoic membrane. The majority of the chicks live until the time of hatching and show no gross changes attributable to the virus and only slight and inconstant microscopical changes in the brain. The membranes show a gross edema and fine granulation of the surface. Microscopically, they show chiefly edema and cellular infiltration of the mesoderm and foci of ectodermal proliferation with superimposed necrosis of the superficial layers.